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diff --git a/38015-8.txt b/38015-8.txt new file mode 100644 index 0000000..c0e6eff --- /dev/null +++ b/38015-8.txt @@ -0,0 +1,34601 @@ +The Project Gutenberg EBook of De Re Metallica, by Georgius Agricola + +This eBook is for the use of anyone anywhere at no cost and with +almost no restrictions whatsoever. You may copy it, give it away or +re-use it under the terms of the Project Gutenberg License included +with this eBook or online at www.gutenberg.org + + +Title: De Re Metallica + Translated from the First Latin Edition of 1556 + +Author: Georgius Agricola + +Translator: Herbert Clark Hoover + Lou Henry Hoover + +Release Date: November 14, 2011 [EBook #38015] + +Language: English + +Character set encoding: ISO-8859-1 + +*** START OF THIS PROJECT GUTENBERG EBOOK DE RE METALLICA *** + + + + +Produced by Malcolm Farmer, Stephen H. Sentoff and the +Online Distributed Proofreading Team at https://www.pgdp.net + + + + + + + + +GEORGIUS AGRICOLA + +DE RE METALLICA + +TRANSLATED FROM THE FIRST LATIN EDITION OF 1556 + +with + +Biographical Introduction, Annotations and Appendices upon +the Development of Mining Methods, Metallurgical +Processes, Geology, Mineralogy & Mining Law +from the earliest times to the 16th Century + +BY + +HERBERT CLARK HOOVER + +A. B. Stanford University, Member American Institute of Mining Engineers, +Mining and Metallurgical Society of America, Société des Ingéniéurs +Civils de France, American Institute of Civil Engineers, +Fellow Royal Geographical Society, etc., etc. + +AND + +LOU HENRY HOOVER + +A. B. Stanford University, Member American Association for the +Advancement of Science, The National Geographical Society, +Royal Scottish Geographical Society, etc., etc. + +1950 + +_Dover Publications, Inc._ + +NEW YORK + + + + +TO + +JOHN CASPAR BRANNER Ph.D., + +_The inspiration of whose teaching is no less great than his +contribution to science._ + +This New 1950 Edition of DE RE METALLICA is a complete and unchanged +reprint of the translation published by The Mining Magazine, London, in +1912. It has been made available through the kind permission of +Honorable Herbert C. Hoover and Mr. Edgar Rickard, Author and Publisher, +respectively, of the original volume. + +PRINTED IN THE UNITED STATES OF AMERICA + + + + +TRANSLATORS' PREFACE. + + +There are three objectives in translation of works of this character: to +give a faithful, literal translation of the author's statements; to give +these in a manner which will interest the reader; and to preserve, so +far as is possible, the style of the original text. The task has been +doubly difficult in this work because, in using Latin, the author +availed himself of a medium which had ceased to expand a thousand years +before his subject had in many particulars come into being; in +consequence he was in difficulties with a large number of ideas for +which there were no corresponding words in the vocabulary at his +command, and instead of adopting into the text his native German terms, +he coined several hundred Latin expressions to answer his needs. It is +upon this rock that most former attempts at translation have been +wrecked. Except for a very small number, we believe we have been able to +discover the intended meaning of such expressions from a study of the +context, assisted by a very incomplete glossary prepared by the author +himself, and by an exhaustive investigation into the literature of these +subjects during the sixteenth and seventeenth centuries. That discovery +in this particular has been only gradual and obtained after much labour, +may be indicated by the fact that the entire text has been +re-typewritten three times since the original, and some parts more +often; and further, that the printer's proof has been thrice revised. We +have found some English equivalent, more or less satisfactory, for +practically all such terms, except those of weights, the varieties of +veins, and a few minerals. In the matter of weights we have introduced +the original Latin, because it is impossible to give true equivalents +and avoid the fractions of reduction; and further, as explained in the +Appendix on Weights it is impossible to say in many cases what scale the +Author had in mind. The English nomenclature to be adopted has given +great difficulty, for various reasons; among them, that many methods and +processes described have never been practised in English-speaking mining +communities, and so had no representatives in our vocabulary, and we +considered the introduction of German terms undesirable; other methods +and processes have become obsolete and their descriptive terms with +them, yet we wished to avoid the introduction of obsolete or unusual +English; but of the greatest importance of all has been the necessity to +avoid rigorously such modern technical terms as would imply a greater +scientific understanding than the period possessed. + +Agricola's Latin, while mostly free from mediæval corruption, is +somewhat tainted with German construction. Moreover some portions have +not the continuous flow of sustained thought which others display, but +the fact that the writing of the work extended over a period of twenty +years, sufficiently explains the considerable variation in style. The +technical descriptions in the later books often take the form of +House-that-Jack-built sentences which have had to be at least partially +broken up and the subject occasionally re-introduced. Ambiguities were +also sometimes found which it was necessary to carry on into the +translation. Despite these criticisms we must, however, emphasize that +Agricola was infinitely clearer in his style than his contemporaries +upon such subjects, or for that matter than his successors in almost any +language for a couple of centuries. All of the illustrations and display +letters of the original have been reproduced and the type as closely +approximates to the original as the printers have been able to find in a +modern font. + +There are no footnotes in the original text, and Mr. Hoover is +responsible for them all. He has attempted in them to give not only such +comment as would tend to clarify the text, but also such information as +we have been able to discover with regard to the previous history of the +subjects mentioned. We have confined the historical notes to the time +prior to Agricola, because to have carried them down to date in the +briefest manner would have demanded very much more space than could be +allowed. In the examination of such technical and historical material +one is appalled at the flood of mis-information with regard to ancient +arts and sciences which has been let loose upon the world by the hands +of non-technical translators and commentators. At an early stage we +considered that we must justify any divergence of view from such +authorities, but to limit the already alarming volume of this work, we +later felt compelled to eliminate most of such discussion. When the +half-dozen most important of the ancient works bearing upon science have +been translated by those of some scientific experience, such questions +will, no doubt, be properly settled. + +We need make no apologies for _De Re Metallica_. During 180 years it was +not superseded as the text-book and guide to miners and metallurgists, +for until Schlüter's great work on metallurgy in 1738 it had no equal. +That it passed through some ten editions in three languages at a period +when the printing of such a volume was no ordinary undertaking, is in +itself sufficient evidence of the importance in which it was held, and +is a record that no other volume upon the same subjects has equalled +since. A large proportion of the technical data given by Agricola was +either entirely new, or had not been given previously with sufficient +detail and explanation to have enabled a worker in these arts himself to +perform the operations without further guidance. Practically the whole +of it must have been given from personal experience and observation, for +the scant library at his service can be appreciated from his own +Preface. Considering the part which the metallic arts have played in +human history, the paucity of their literature down to Agricola's time +is amazing. No doubt the arts were jealously guarded by their +practitioners as a sort of stock-in-trade, and it is also probable that +those who had knowledge were not usually of a literary turn of mind; +and, on the other hand, the small army of writers prior to his time +were not much interested in the description of industrial pursuits. +Moreover, in those thousands of years prior to printing, the tedious and +expensive transcription of manuscripts by hand was mostly applied to +matters of more general interest, and therefore many writings may have +been lost in consequence. In fact, such was the fate of the works of +Theophrastus and Strato on these subjects. + +We have prepared a short sketch of Agricola's life and times, not only +to give some indication of his learning and character, but also of his +considerable position in the community in which he lived. As no +appreciation of Agricola's stature among the founders of science can be +gained without consideration of the advance which his works display over +those of his predecessors, we therefore devote some attention to the +state of knowledge of these subjects at the time by giving in the +Appendix a short review of the literature then extant and a summary of +Agricola's other writings. To serve the bibliophile we present such data +as we have been able to collect it with regard to the various editions +of his works. The full titles of the works quoted in the footnotes under +simply authors' names will be found in this Appendix. + +We feel that it is scarcely doing Agricola justice to publish _De Re +Metallica_ only. While it is of the most general interest of all of his +works, yet, from the point of view of pure science, _De Natura +Fossilium_ and _De Ortu et Causis_ are works which deserve an equally +important place. It is unfortunate that Agricola's own countrymen have +not given to the world competent translations into German, as his work +has too often been judged by the German translations, the infidelity of +which appears in nearly every paragraph. + +We do not present _De Re Metallica_ as a work of "practical" value. The +methods and processes have long since been superseded; yet surely such a +milestone on the road of development of one of the two most basic of +human industrial activities is more worthy of preservation than the +thousands of volumes devoted to records of human destruction. To those +interested in the history of their own profession we need make no +apologies, except for the long delay in publication. For this we put +forward the necessity of active endeavour in many directions; as this +book could be but a labour of love, it has had to find the moments for +its execution in night hours, weekends, and holidays, in all extending +over a period of about five years. If the work serves to strengthen the +traditions of one of the most important and least recognized of the +world's professions we shall be amply repaid. + +It is our pleasure to acknowledge our obligations to Professor H. R. +Fairclough, of Stanford University, for perusal of and suggestions upon +the first chapter; and to those whom we have engaged from time to time +for one service or another, chiefly bibliographical work and collateral +translation. We are also sensibly obligated to the printers, Messrs. +Frost & Sons, for their patience and interest, and for their willingness +to bend some of the canons of modern printing, to meet the demands of +the 16th Century. + + _July 1, 1912._ + + The Red House, + Hornton Street, London. + + + + +INTRODUCTION. + + +BIOGRAPHY.[1] + +Georgius Agricola was born at Glauchau, in Saxony, on March 24th, 1494, +and therefore entered the world when it was still upon the threshold of +the Renaissance; Gutenberg's first book had been printed but forty years +before; the Humanists had but begun that stimulating criticism which +awoke the Reformation; Erasmus, of Rotterdam, who was subsequently to +become Agricola's friend and patron, was just completing his student +days. The Reformation itself was yet to come, but it was not long +delayed, for Luther was born the year before Agricola, and through him +Agricola's homeland became the cradle of the great movement; nor did +Agricola escape being drawn into the conflict. Italy, already awake with +the new classical revival, was still a busy workshop of antiquarian +research, translation, study, and publication, and through her the Greek +and Latin Classics were only now available for wide distribution. +Students from the rest of Europe, among them at a later time Agricola +himself, flocked to the Italian Universities, and on their return +infected their native cities with the newly-awakened learning. At +Agricola's birth Columbus had just returned from his great discovery, +and it was only three years later that Vasco Da Gama rounded Cape Good +Hope. Thus these two foremost explorers had only initiated that greatest +period of geographical expansion in the world's history. A few dates +will recall how far this exploration extended during Agricola's +lifetime. Balboa first saw the Pacific in 1513; Cortes entered the City +of Mexico in 1520; Magellan entered the Pacific in the same year; +Pizarro penetrated into Peru in 1528; De Soto landed in Florida in 1539, +and Potosi was discovered in 1546. Omitting the sporadic settlement on +the St. Lawrence by Cartier in 1541, the settlement of North America did +not begin for a quarter of a century after Agricola's death. Thus the +revival of learning, with its train of Humanism, the Reformation, its +stimulation of exploration and the re-awakening of the arts and +sciences, was still in its infancy with Agricola. + +We know practically nothing of Agricola's antecedents or his youth. His +real name was Georg Bauer ("peasant"), and it was probably Latinized by +his teachers, as was the custom of the time. His own brother, in +receipts preserved in the archives of the Zwickau Town Council, calls +himself "Bauer," and in them refers to his brother "Agricola." He +entered the University of Leipsic at the age of twenty, and after about +three and one-half years' attendance there gained the degree of +_Baccalaureus Artium_. In 1518 he became Vice-Principal of the Municipal +School at Zwickau, where he taught Greek and Latin. In 1520 he became +Principal, and among his assistants was Johannes Förster, better known +as Luther's collaborator in the translation of the Bible. During this +time our author prepared and published a small Latin Grammar[2]. In 1522 +he removed to Leipsic to become a lecturer in the University under his +friend, Petrus Mosellanus, at whose death in 1524 he went to Italy for +the further study of Philosophy, Medicine, and the Natural Sciences. +Here he remained for nearly three years, from 1524 to 1526. He visited +the Universities of Bologna, Venice, and probably Padua, and at these +institutions received his first inspiration to work in the sciences, for +in a letter[3] from Leonardus Casibrotius to Erasmus we learn that he +was engaged upon a revision of Galen. It was about this time that he +made the acquaintance of Erasmus, who had settled at Basel as Editor for +Froben's press. + +In 1526 Agricola returned to Zwickau, and in 1527 he was chosen town +physician at Joachimsthal. This little city in Bohemia is located on the +eastern slope of the Erzgebirge, in the midst of the then most prolific +metal-mining district of Central Europe. Thence to Freiberg is but fifty +miles, and the same radius from that city would include most of the +mining towns so frequently mentioned in _De Re Metallica_--Schneeberg, +Geyer, Annaberg and Altenberg--and not far away were Marienberg, +Gottesgab, and Platten. Joachimsthal was a booming mining camp, founded +but eleven years before Agricola's arrival, and already having several +thousand inhabitants. According to Agricola's own statement[4], he spent +all the time not required for his medical duties in visiting the mines +and smelters, in reading up in the Greek and Latin authors all +references to mining, and in association with the most learned among the +mining folk. Among these was one Lorenz Berman, whom Agricola afterward +set up as the "learned miner" in his dialogue _Bermannus_. This book was +first published by Froben at Basel in 1530, and was a sort of catechism +on mineralogy, mining terms, and mining lore. The book was apparently +first submitted to the great Erasmus, and the publication arranged by +him, a warm letter of approval by him appearing at the beginning of the +book[5]. In 1533 he published _De Mensuris et Ponderibus_, through +Froben, this being a discussion of Roman and Greek weights and measures. +At about this time he began _De Re Metallica_--not to be published for +twenty-five years. + +Agricola did not confine his interest entirely to medicine and mining, +for during this period he composed a pamphlet upon the Turks, urging +their extermination by the European powers. This work was no doubt +inspired by the Turkish siege of Vienna in 1529. It appeared first in +German in 1531, and in Latin--in which it was originally written--in +1538, and passed through many subsequent editions. + +At this time, too, he became interested in the God's Gift mine at +Abertham, which was discovered in 1530. Writing in 1545, he says[6]: +"We, as a shareholder, through the goodness of God, have enjoyed the +proceeds of this God's Gift since the very time when the mine began +first to bestow such riches." + +Agricola seems to have resigned his position at Joachimsthal in about +1530, and to have devoted the next two or three years to travel and +study among the mines. About 1533 he became city physician of Chemnitz, +in Saxony, and here he resided until his death in 1555. There is but +little record of his activities during the first eight or nine years of +his residence in this city. He must have been engaged upon the study of +his subjects and the preparation of his books, for they came on with +great rapidity soon after. He was frequently consulted on matters of +mining engineering, as, for instance, we learn, from a letter written by +a certain Johannes Hordeborch[7], that Duke Henry of Brunswick applied +to him with regard to the method for working mines in the Upper Harz. + +In 1543 he married Anna, widow of Matthias Meyner, a petty tithe +official; there is some reason to believe from a letter published by +Schmid,[8] that Anna was his second wife, and that he was married the +first time at Joachimsthal. He seems to have had several children, for +he commends his young children to the care of the Town Council during +his absence at the war in 1547. In addition to these, we know that a +son, Theodor, was born in 1550; a daughter, Anna, in 1552; another +daughter, Irene, was buried at Chemnitz in 1555; and in 1580 his widow +and three children--Anna, Valerius, and Lucretia--were still living. + +In 1544 began the publication of the series of books to which Agricola +owes his position. The first volume comprised five works and was finally +issued in 1546; it was subsequently considerably revised, and re-issued +in 1558. These works were: _De Ortu et Causis Subterraneorum_, in five +"books," the first work on physical geology; _De Natura Eorum quae +Effluunt ex Terra_, in four "books," on subterranean waters and gases; +_De Natura Fossilium_, in ten "books," the first systematic mineralogy; +_De Veteribus et Novis Metallis_, in two "books," devoted largely to the +history of metals and topographical mineralogy; a new edition of +_Bermannus_ was included; and finally _Rerum Metallicarum +Interpretatio_, a glossary of Latin and German mineralogical and +metallurgical terms. Another work, _De Animantibus Subterraneis_, +usually published with _De Re Metallica_, is dated 1548 in the preface. +It is devoted to animals which live underground, at least part of the +time, but is not a very effective basis of either geologic or zoologic +classification. Despite many public activities, Agricola apparently +completed _De Re Metallica_ in 1550, but did not send it to the press +until 1553; nor did it appear until a year after his death in 1555. But +we give further details on the preparation of this work on p. xv. During +this period he found time to prepare a small medical work, _De Peste_, +and certain historical studies, details of which appear in the Appendix. +There are other works by Agricola referred to by sixteenth century +writers, but so far we have not been able to find them although they may +exist. Such data as we have, is given in the appendix. + +As a young man, Agricola seems to have had some tendencies toward +liberalism in religious matters, for while at Zwickau he composed some +anti-Popish Epigrams; but after his return to Leipsic he apparently +never wavered, and steadily refused to accept the Lutheran Reformation. +To many even liberal scholars of the day, Luther's doctrines appeared +wild and demagogic. Luther was not a scholarly man; his addresses were +to the masses; his Latin was execrable. Nor did the bitter dissensions +over hair-splitting theology in the Lutheran Church after Luther's death +tend to increase respect for the movement among the learned. Agricola +was a scholar of wide attainments, a deep-thinking, religious man, and +he remained to the end a staunch Catholic, despite the general change of +sentiment among his countrymen. His leanings were toward such men as his +friend the humanist, Erasmus. That he had the courage of his convictions +is shown in the dedication of _De Natura Eorum_, where he addresses to +his friend, Duke Maurice, the pious advice that the dissensions of the +Germans should be composed, and that the Duke should return to the bosom +of the Church those who had been torn from her, and adds: "Yet I do not +wish to become confused by these turbulent waters, and be led to offend +anyone. It is more advisable to check my utterances." As he became older +he may have become less tolerant in religious matters, for he did not +seem to show as much patience in the discussion of ecclesiastical topics +as he must have possessed earlier, yet he maintained to the end the +respect and friendship of such great Protestants as Melanchthon, +Camerarius, Fabricius, and many others. + +In 1546, when he was at the age of 52, began Agricola's activity in +public life, for in that year he was elected a Burgher of Chemnitz; and +in the same year Duke Maurice appointed him Burgomaster--an office which +he held for four terms. Before one can gain an insight into his +political services, and incidentally into the character of the man, it +is necessary to understand the politics of the time and his part +therein, and to bear in mind always that he was a staunch Catholic under +a Protestant Sovereign in a State seething with militant Protestantism. + +Saxony had been divided in 1485 between the Princes Ernest and Albert, +the former taking the Electoral dignity and the major portion of the +Principality. Albert the Brave, the younger brother and Duke of Saxony, +obtained the subordinate portion, embracing Meissen, but subject to the +Elector. The Elector Ernest was succeeded in 1486 by Frederick the Wise, +and under his support Luther made Saxony the cradle of the Reformation. +This Elector was succeeded in 1525 by his brother John, who was in turn +succeeded by his son John Frederick in 1532. Of more immediate interest +to this subject is the Albertian line of Saxon Dukes who ruled Meissen, +for in that Principality Agricola was born and lived, and his political +fortunes were associated with this branch of the Saxon House. Albert was +succeeded in 1505 by his son George, "The Bearded," and he in turn by +his brother Henry, the last of the Catholics, in 1539, who ruled until +1541. Henry was succeeded in 1541 by his Protestant son Maurice, who was +the Patron of Agricola. + +At about this time Saxony was drawn into the storms which rose from the +long-standing rivalry between Francis I., King of France, and Charles V. +of Spain. These two potentates came to the throne in the same year +(1515), and both were candidates for Emperor of that loose Confederation +known as the Holy Roman Empire. Charles was elected, and intermittent +wars between these two Princes arose--first in one part of Europe, and +then in another. Francis finally formed an alliance with the +Schmalkalden League of German Protestant Princes, and with the Sultan of +Turkey, against Charles. In 1546 Maurice of Meissen, although a +Protestant, saw his best interest in a secret league with Charles +against the other Protestant Princes, and proceeded (the Schmalkalden +War) to invade the domains of his superior and cousin, the Elector +Frederick. The Emperor Charles proved successful in this war, and +Maurice was rewarded, at the Capitulation of Wittenberg in 1547, by +being made Elector of Saxony in the place of his cousin. Later on, the +Elector Maurice found the association with Catholic Charles unpalatable, +and joined in leading the other Protestant princes in war upon him, and +on the defeat of the Catholic party and the peace of Passau, Maurice +became acknowledged as the champion of German national and religious +freedom. He was succeeded by his brother Augustus in 1553. + +Agricola was much favoured by the Saxon Electors, Maurice and Augustus. +He dedicates most of his works to them, and shows much gratitude for +many favours conferred upon him. Duke Maurice presented to him a house +and plot in Chemnitz, and in a letter dated June 14th, 1543[9] in +connection therewith, says: "... that he may enjoy his life-long a +freehold house unburdened by all burgher rights and other municipal +service, to be used by him and inhabited as a free dwelling, and that he +may also, for the necessities of his household and of his wife and +servants, brew his own beer free, and that he may likewise purvey for +himself and his household foreign beer and also wine for use, and yet he +shall not sell any such beer.... We have taken the said Doctor under our +especial protection and care for our life-long, and he shall not be +summoned before any Court of Justice, but only before us and our +Councillor...." + +Agricola was made Burgomaster of Chemnitz in 1546. A letter[10] from +Fabricius to Meurer, dated May 19th, 1546, says that Agricola had been +made Burgomaster by the command of the Prince. This would be Maurice, +and it is all the more a tribute to the high respect with which Agricola +was held, for, as said before, he was a consistent Catholic, and Maurice +a Protestant Prince. In this same year the Schmalkalden War broke out, +and Agricola was called to personal attendance upon the Duke Maurice in +a diplomatic and advisory capacity. In 1546 also he was a member of the +Diet of Freiberg, and was summoned to Council in Dresden. The next year +he continued, by the Duke's command, Burgomaster at Chemnitz, although +he seems to have been away upon Ducal matters most of the time. The Duke +addresses[11] the Chemnitz Council in March, 1547: "We hereby make known +to you that we are in urgent need of your Burgomaster, Dr. Georgius +Agricola, with us. It is, therefore, our will that you should yield him +up and forward him that he should with the utmost haste set forth to us +here near Freiberg." He was sent on various missions from the Duke to +the Emperor Charles, to King Ferdinand of Austria, and to other Princes +in matters connected with the war--the fact that he was a Catholic +probably entering into his appointment to such missions. Chemnitz was +occupied by the troops of first one side, then the other, despite the +great efforts of Agricola to have his own town specially defended. In +April, 1547, the war came to an end in the Battle of Mühlberg, but +Agricola was apparently not relieved of his Burgomastership until the +succeeding year, for he wrote his friend Wolfgang Meurer, in April, +1548,[12] that he "was now relieved." His public duties did not end, +however, for he attended the Diet of Leipzig in 1547 and in 1549, and +was at the Diet at Torgau in 1550. In 1551 he was again installed as +Burgomaster; and in 1553, for the fourth time, he became head of the +Municipality, and during this year had again to attend the Diets at +Leipzig and Dresden, representing his city. He apparently now had a +short relief from public duties, for it is not until 1555, shortly +before his death, that we find him again attending a Diet at Torgau. + +Agricola died on November 21st, 1555. A letter[13] from his life-long +friend, Fabricius, to Melanchthon, announcing this event, states: "We +lost, on November 21st, that distinguished ornament of our Fatherland, +Georgius Agricola, a man of eminent intellect, of culture and of +judgment. He attained the age of 62. He who since the days of childhood +had enjoyed robust health was carried off by a four-days' fever. He had +previously suffered from no disease except inflammation of the eyes, +which he brought upon himself by untiring study and insatiable +reading.... I know that you loved the soul of this man, although in many +of his opinions, more especially in religious and spiritual welfare, he +differed in many points from our own. For he despised our Churches, and +would not be with us in the Communion of the Blood of Christ. Therefore, +after his death, at the command of the Prince, which was given to the +Church inspectors and carried out by Tettelbach as a loyal servant, +burial was refused him, and not until the fourth day was he borne away +to Zeitz and interred in the Cathedral.... I have always admired the +genius of this man, so distinguished in our sciences and in the whole +realm of Philosophy--yet I wonder at his religious views, which were +compatible with reason, it is true, and were dazzling, but were by no +means compatible with truth.... He would not tolerate with patience that +anyone should discuss ecclesiastical matters with him." This action of +the authorities in denying burial to one of their most honoured +citizens, who had been ever assiduous in furthering the welfare of the +community, seems strangely out of joint. Further, the Elector Augustus, +although a Protestant Prince, was Agricola's warm friend, as evidenced +by his letter of but a few months before (see p. xv). However, Catholics +were then few in number at Chemnitz, and the feeling ran high at the +time, so possibly the Prince was afraid of public disturbances. +Hofmann[14] explains this occurrence in the following words:--"The +feelings of Chemnitz citizens, who were almost exclusively Protestant, +must certainly be taken into account. They may have raised objections to +the solemn interment of a Catholic in the Protestant Cathedral Church of +St. Jacob, which had, perhaps, been demanded by his relatives, and to +which, according to the custom of the time, he would have been entitled +as Burgomaster. The refusal to sanction the interment aroused, more +especially in the Catholic world, a painful sensation." + +A brass memorial plate hung in the Cathedral at Zeitz had already +disappeared in 1686, nor have the cities of his birth or residence ever +shown any appreciation of this man, whose work more deserves their +gratitude than does that of the multitude of soldiers whose monuments +decorate every village and city square. It is true that in 1822 a marble +tablet was placed behind the altar in the Church of St. Jacob in +Chemnitz, but even this was removed to the Historical Museum later on. + +He left a modest estate, which was the subject of considerable +litigation by his descendants, due to the mismanagement of the guardian. +Hofmann has succeeded in tracing the descendants for two generations, +down to 1609, but the line is finally lost among the multitude of other +Agricolas. + +To deduce Georgius Agricola's character we need not search beyond the +discovery of his steadfast adherence to the religion of his fathers amid +the bitter storm of Protestantism around him, and need but to remember +at the same time that for twenty-five years he was entrusted with +elective positions of an increasingly important character in this same +community. No man could have thus held the respect of his countrymen +unless he were devoid of bigotry and possessed of the highest sense of +integrity, justice, humanity, and patriotism. + + +AGRICOLA'S INTELLECTUAL ATTAINMENTS AND POSITION IN SCIENCE. + +Agricola's education was the most thorough that his times afforded in +the classics, philosophy, medicine, and sciences generally. Further, his +writings disclose a most exhaustive knowledge not only of an +extraordinary range of classical literature, but also of obscure +manuscripts buried in the public libraries of Europe. That his general +learning was held to be of a high order is amply evidenced from the +correspondence of the other scholars of his time--Erasmus, Melanchthon, +Meurer, Fabricius, and others. + +Our more immediate concern, however, is with the advances which were due +to him in the sciences of Geology, Mineralogy, and Mining Engineering. +No appreciation of these attainments can be conveyed to the reader +unless he has some understanding of the dearth of knowledge in these +sciences prior to Agricola's time. We have in Appendix B given a brief +review of the literature extant at this period on these subjects. +Furthermore, no appreciation of Agricola's contribution to science can +be gained without a study of _De Ortu et Causis_ and _De Natura +Fossilium_, for while _De Re Metallica_ is of much more general +interest, it contains but incidental reference to Geology and +Mineralogy. Apart from the book of Genesis, the only attempts at +fundamental explanation of natural phenomena were those of the Greek +Philosophers and the Alchemists. Orthodox beliefs Agricola scarcely +mentions; with the Alchemists he had no patience. There can be no doubt, +however, that his views are greatly coloured by his deep classical +learning. He was in fine to a certain distance a follower of Aristotle, +Theophrastus, Strato, and other leaders of the Peripatetic school. For +that matter, except for the muddy current which the alchemists had +introduced into this already troubled stream, the whole thought of the +learned world still flowed from the Greeks. Had he not, however, +radically departed from the teachings of the Peripatetic school, his +work would have been no contribution to the development of science. +Certain of their teachings he repudiated with great vigour, and his +laboured and detailed arguments in their refutation form the first +battle in science over the results of observation _versus_ inductive +speculation. To use his own words: "Those things which we see with our +eyes and understand by means of our senses are more clearly to be +demonstrated than if learned by means of reasoning."[15] The bigoted +scholasticism of his times necessitated as much care and detail in +refutation of such deep-rooted beliefs, as would be demanded to-day by +an attempt at a refutation of the theory of evolution, and in +consequence his works are often but dry reading to any but those +interested in the development of fundamental scientific theory. + +In giving an appreciation of Agricola's views here and throughout the +footnotes, we do not wish to convey to the reader that he was in all +things free from error and from the spirit of his times, or that his +theories, constructed long before the atomic theory, are of the +clear-cut order which that basic hypothesis has rendered possible to +later scientific speculation in these branches. His statements are +sometimes much confused, but we reiterate that their clarity is as +crystal to mud in comparison with those of his predecessors--and of most +of his successors for over two hundred years. As an indication of his +grasp of some of the wider aspects of geological phenomena we reproduce, +in Appendix A, a passage from _De Ortu et Causis_, which we believe to +be the first adequate declaration of the part played by erosion in +mountain sculpture. But of all of Agricola's theoretical views those are +of the greatest interest which relate to the origin of ore deposits, for +in these matters he had the greatest opportunities of observation and +the most experience. We have on page 108 reproduced and discussed his +theory at considerable length, but we may repeat here, that in his +propositions as to the circulation of ground waters, that ore channels +are a subsequent creation to the contained rocks, and that they were +filled by deposition from circulating solutions, he enunciated the +foundations of our modern theory, and in so doing took a step in advance +greater than that of any single subsequent authority. In his contention +that ore channels were created by erosion of subterranean waters he was +wrong, except for special cases, and it was not until two centuries +later that a further step in advance was taken by the recognition by Van +Oppel of the part played by fissuring in these phenomena. Nor was it +until about the same time that the filling of ore channels in the main +by deposition from solutions was generally accepted. While Werner, two +hundred and fifty years after Agricola, is generally revered as the +inspirer of the modern theory by those whose reading has taken them no +farther back, we have no hesitation in asserting that of the +propositions of each author, Agricola's were very much more nearly in +accord with modern views. Moreover, the main result of the new ideas +brought forward by Werner was to stop the march of progress for half a +century, instead of speeding it forward as did those of Agricola. + +In mineralogy Agricola made the first attempt at systematic treatment of +the subject. His system could not be otherwise than wrongly based, as he +could scarcely see forward two or three centuries to the atomic theory +and our vast fund of chemical knowledge. However, based as it is upon +such properties as solubility and homogeneity, and upon external +characteristics such as colour, hardness, &c., it makes a most +creditable advance upon Theophrastus, Dioscorides, and Albertus +Magnus--his only predecessors. He is the first to assert that bismuth +and antimony are true primary metals; and to some sixty actual mineral +species described previous to his time he added some twenty more, and +laments that there are scores unnamed. + +As to Agricola's contribution to the sciences of mining and metallurgy, +_De Re Metallica_ speaks for itself. While he describes, for the first +time, scores of methods and processes, no one would contend that they +were discoveries or inventions of his own. They represent the +accumulation of generations of experience and knowledge; but by him they +were, for the first time, to receive detailed and intelligent +exposition. Until Schlüter's work nearly two centuries later, it was not +excelled. There is no measure by which we may gauge the value of such a +work to the men who followed in this profession during centuries, nor +the benefits enjoyed by humanity through them. + +That Agricola occupied a very considerable place in the great awakening +of learning will be disputed by none except by those who place the +development of science in rank far below religion, politics, literature, +and art. Of wider importance than the details of his achievements in the +mere confines of the particular science to which he applied himself, is +the fact that he was the first to found any of the natural sciences upon +research and observation, as opposed to previous fruitless speculation. +The wider interest of the members of the medical profession in the +development of their science than that of geologists in theirs, has led +to the aggrandizement of Paracelsus, a contemporary of Agricola, as the +first in deductive science. Yet no comparative study of the unparalleled +egotistical ravings of this half-genius, half-alchemist, with the modest +sober logic and real research and observation of Agricola, can leave a +moment's doubt as to the incomparably greater position which should be +attributed to the latter as the pioneer in building the foundation of +science by deduction from observed phenomena. Science is the base upon +which is reared the civilization of to-day, and while we give daily +credit to all those who toil in the superstructure, let none forget +those men who laid its first foundation stones. One of the greatest of +these was Georgius Agricola. + + +DE RE METALLICA + +Agricola seems to have been engaged in the preparation of _De Re +Metallica_ for a period of over twenty years, for we first hear of the +book in a letter from Petrus Plateanus, a schoolmaster at Joachimsthal, +to the great humanist, Erasmus,[16] in September, 1529. He says: "The +scientific world will be still more indebted to Agricola when he brings +to light the books _De Re Metallica_ and other matters which he has on +hand." In the dedication of _De Mensuris et Ponderibus_ (in 1533) +Agricola states that he means to publish twelve books _De Re Metallica_, +if he lives. That the appearance of this work was eagerly anticipated is +evidenced by a letter from George Fabricius to Valentine Hertel:[17] +"With great excitement the books _De Re Metallica_ are being awaited. If +he treats the material at hand with his usual zeal, he will win for +himself glory such as no one in any of the fields of literature has +attained for the last thousand years." According to the dedication of +_De Veteribus et Novis Metallis_, Agricola in 1546 already looked +forward to its early publication. The work was apparently finished in +1550, for the dedication to the Dukes Maurice and August of Saxony is +dated in December of that year. The eulogistic poem by his friend, +George Fabricius, is dated in 1551. + +The publication was apparently long delayed by the preparation of the +woodcuts; and, according to Mathesius,[18] many sketches for them were +prepared by Basilius Wefring. In the preface of _De Re Metallica_, +Agricola does not mention who prepared the sketches, but does say: "I +have hired illustrators to delineate their forms, lest descriptions +which are conveyed by words should either not be understood by men of +our own times, or should cause difficulty to posterity." In 1553 the +completed book was sent to Froben for publication, for a letter[19] from +Fabricius to Meurer in March, 1553, announces its dispatch to the +printer. An interesting letter[20] from the Elector Augustus to +Agricola, dated January 18, 1555, reads: "Most learned, dear and +faithful subject, whereas you have sent to the Press a Latin book of +which the title is said to be _De Rebus Metallicis_, which has been +praised to us and we should like to know the contents, it is our +gracious command that you should get the book translated when you have +the opportunity into German, and not let it be copied more than once or +be printed, but keep it by you and send us a copy. If you should need a +writer for this purpose, we will provide one. Thus you will fulfil our +gracious behest." The German translation was prepared by Philip Bechius, +a Basel University Professor of Medicine and Philosophy. It is a +wretched work, by one who knew nothing of the science, and who more +especially had no appreciation of the peculiar Latin terms coined by +Agricola, most of which he rendered literally. It is a sad commentary +on his countrymen that no correct German translation exists. The Italian +translation is by Michelangelo Florio, and is by him dedicated to +Elizabeth, Queen of England. The title page of the first edition is +reproduced later on, and the full titles of other editions are given in +the Appendix, together with the author's other works. The following are +the short titles of the various editions of _De Re Metallica_, together +with the name and place of the publisher:-- + +Latin Editions. + + _De Re Metallica_, Froben Basel Folio 1556. + " " " " " " 1561. + " " " Ludwig König " " 1621. + " " " Emanuel König " " 1657. + +In addition to these, Leupold,[21] Schmid,[22] and others mention an +octavo edition, without illustrations, Schweinfurt, 1607. We have not +been able to find a copy of this edition, and are not certain of its +existence. The same catalogues also mention an octavo edition of _De Re +Metallica_, Wittenberg, 1612 or 1614, with notes by Joanne Sigfrido; but +we believe this to be a confusion with Agricola's subsidiary works, +which were published at this time and place, with such notes. + +German Editions. + + _Vom Bergkwerck_, Froben, Folio, 1557. + _Bergwerck Buch_, Sigmundi Feyrabendt, Frankfort-on-Main, folio, 1580. + " " Ludwig König, Basel, folio, 1621. + +There are other editions than these, mentioned by bibliographers, but we +have been unable to confirm them in any library. The most reliable of +such bibliographies, that of John Ferguson,[23] gives in addition to the +above; _Bergwerkbuch_, Basel, 1657, folio, and Schweinfurt, 1687, +octavo. + +Italian Edition. + +_L'Arte de Metalli_, Froben, Basel, folio, 1563. + +Other Languages. + +So far as we know, _De Re Metallica_ was never actually published in +other than Latin, German, and Italian. However, a portion of the +accounts of the firm of Froben were published in 1881[24], and therein +is an entry under March, 1560, of a sum to one Leodigaris Grymaldo for +some other work, and also for "correction of Agricola's _De Re +Metallica_ in French." This may of course, be an error for the Italian +edition, which appeared a little later. There is also mention[25] that a +manuscript of _De Re Metallica_ in Spanish was seen in the library of +the town of Bejar. An interesting note appears in the glossary given by +Sir John Pettus in his translation of Lazarus Erckern's work on +assaying. He says[26] "but I cannot enlarge my observations upon any +more words, because the printer calls for what I did write of a +metallick dictionary, after I first proposed the printing of Erckern, +but intending within the compass of a year to publish Georgius Agricola, +_De Re Metallica_ (being fully translated) in English, and also to add a +dictionary to it, I shall reserve my remaining essays (if what I have +done hitherto be approved) till then, and so I proceed in the +dictionary." The translation was never published and extensive inquiry +in various libraries and among the family of Pettus has failed to yield +any trace of the manuscript. + + +FOOTNOTES: + +[1] For the biographical information here set out we have relied +principally upon the following works:--Petrus Albinus, _Meissnische Land +Und Berg Chronica_, Dresden, 1590; Adam Daniel Richter, _Umständliche +... Chronica der Stadt Chemnitz_, Leipzig, 1754; Johann Gottfried +Weller, _Altes Aus Allen Theilen Der Geschichte_, Chemnitz, 1766; +Freidrich August Schmid, _Georg Agrikola's Bermannus_, Freiberg, 1806; +Georg Heinrich Jacobi, _Der Mineralog Georgius Agricola_, Zwickau, 1881; +Dr. Reinhold Hofmann, _Dr. Georg Agricola_, Gotha, 1905. The last is an +exhaustive biographical sketch, to which we refer those who are +interested. + +[2] _Georgii Agricolae Glaucii Libellus de Prima ac Simplici +Institutione Grammatica_, printed by Melchior Lotther, Leipzig, 1520. +Petrus Mosellanus refers to this work (without giving title) in a letter +to Agricola, June, 1520. + +[3] _Briefe an Desiderius Erasmus von Rotterdam._ Published by Joseph +Förstemann and Otto Günther. _XXVII. Beiheft zum Zentralblatt für +Bibliothekswesen_, Leipzig, 1904. p. 44. + +[4] _De Veteribus et Novis Metallis._ Preface. + +[5] A summary of this and of Agricola's other works is given in the +Appendix A. + +[6] _De Veteribus et Novis Metallis_, Book I. + +[7] Printed in F. A. Schmid's _Georg Agrikola's Bermannus_, p. 14, +Freiberg, 1806. + +[8] Op. Cit., p. 8. + +[9] Archive 38, Chemnitz Municipal Archives. + +[10] Baumgarten-Crusius. _Georgii Fabricii Chemnicensis Epistolae ad W. +Meurerum et Alios Aequales_, Leipzig, 1845, p. 26. + +[11] Hofmann, Op. cit., p. 99. + +[12] Weber, _Virorum Clarorum Saeculi XVI. et XVII. Epistolae +Selectae_, Leipzig, 1894, p. 8. + +[13] Baumgarten-Crusius. Op. cit., p. 139. + +[14] Hofmann, Op. cit., p. 123. + +[15] _De Ortu et Causis_, Book III. + +[16] _Briefe an Desiderius Erasmus von Rotterdam._ Published by Joseph +Förstemann & Otto Günther. _XXVII. Beiheft zum Zentralblatt für +Bibliothekswesen_, Leipzig, 1904, p. 125. + +[17] Petrus Albinus, _Meissnische Land und Berg Chronica_, Dresden, +1590, p. 353. + +[18] This statement is contained under "1556" in a sort of chronicle +bound up with Mathesius's _Sarepta_, Nuremberg, 1562. + +[19] Baumgarten-Crusius, p. 85, letter No. 93. + +[20] Principal State Archives, Dresden, Cop. 259, folio 102. + +[21] Jacob Leupold, _Prodromus Bibliothecae Metallicae_, 1732, p. 11. + +[22] F. A. Schmid, _Georg Agrikola's Bermannus_, Freiberg, 1806, p. 34. + +[23] _Bibliotheca Chemica_, Glasgow, 1906, p. 10. + +[24] _Rechnungsbuch der Froben und Episcopius Buchdrucker und +Buchhändler zu Basel_, 1557-1564, published by R. Wackernagle, Basel, +1881. p. 20. + +[25] _Colecion del Sr Monoz_ t. 93, fol. 255 _En la Acad. de la Hist._ +Madrid. + +[26] Sir John Pettus, _Fleta Minor_, The Laws of Art and Nature, &c., +London, 1636, p. 121. + + + + +[Illustration xix (Title page from first edition)] + + + + + GEORGIUS FABRICIUS IN LIBROS + Metallicos GEORGII AGRICOLAE philosophi + præstantissimi.[1] + +AD LECTOREM. + + Si iuuat ignita cognoscere fronte Chimæram, + Semicanem nympham, semibouemque uirum: + Si centum capitum Titanem, totque ferentem + Sublimem manibus tela cruenta Gygen: + Si iuuat Ætneum penetrare Cyclopis in antrum, + Atque alios, Vates quos peperere, metus: + Nunc placeat mecum doctos euoluere libros, + Ingenium AGRICOLAE quos dedit acre tibi. + Non hic uana tenet suspensam fabula mentem: + Sed precium, utilitas multa, legentis erit. + Quidquid terra sinu, gremioque recondidit imo, + Omne tibi multis eruit ante libris: + Siue fluens superas ultro nitatur in oras, + Inueniat facilem seu magis arte uiam. + Perpetui proprijs manant de fontibus amnes, + Est grauis Albuneæ sponte Mephitis odor. + Lethales sunt sponte scrobes Dicæarchidis oræ, + Et micat è media conditus ignis humo. + Plana Nariscorum cùm tellus arsit in agro, + Ter curua nondum falce resecta Ceres, + Nec dedit hoc damnum pastor, nec Iuppiter igne: + Vulcani per se ruperat ira solum. + Terrifico aura foras erumpens, incita motu, + Sæpe facit montes, antè ubi plana uia est. + Hæc abstrusa cauis, imoque incognita fundo, + Cognita natura sæpe fuere duce. + Arte hominum, in lucem ueniunt quoque multa, manuque + Terræ multiplices effodiuntur opes. + Lydia sic nitrum profert, Islandia sulfur, + Ac modò Tyrrhenus mittit alumen ager. + Succina, quâ trifido subit æquor Vistula cornu, + Piscantur Codano corpora serua sinu. + Quid memorem regum preciosa insignia gemmas, + Marmoraque excelsis structa sub astra iugis? + Nil lapides, nil saxa moror: sunt pulchra metalla, + Croese tuis opibus clara, Mydaque tuis, + Quæque acer Macedo terra Creneide fodit, + Nomine permutans nomina prisca suo. + At nunc non ullis cedit GERMANIA terris, + Terra ferax hominum, terraque diues opum. + Hic auri in uenis locupletibus aura refulget, + Non alio messis carior ulla loco. + Auricomum extulerit felix Campania ramum, + Nec fructu nobis deficiente cadit. + Eruit argenti solidas hoc tempore massas + Fossor, de proprijs armaque miles agris. + Ignotum Graijs est Hesperijsque metallum, + Quod Bisemutum lingua paterna uocat. + Candidius nigro, sed plumbo nigrius albo, + Nostra quoque hoc uena diuite fundit humus. + Funditur in tormenta, corus cum imitantia fulmen, + Æs, inque hostiles ferrea massa domos. + Scribuntur plumbo libri: quis credidit antè + Quàm mirandam artem Teutonis ora dedit? + Nec tamen hoc alijs, aut illa petuntur ab oris, + Eruta Germano cuncta metalla solo. + Sed quid ego hæc repeto, monumentis tradita claris + AGRICOLAE, quæ nunc docta per ora uolant? + Hic caussis ortus, & formas uiribus addit, + Et quærenda quibus sint meliora locis. + Quæ si mente prius legisti candidus æqua: + Da reliquis quoque nunc tempora pauca libris. + Vtilitas sequitur cultorem: crede, uoluptas + Non iucunda minor, rara legentis, erit. + Iudicioque prius ne quis malè damnet iniquo, + Quæ sunt auctoris munera mira Dei: + Eripit ipse suis primùm tela hostibus, inque + Mittentis torquet spicula rapta caput. + Fertur equo latro, uehitur pirata triremi: + Ergo necandus equus, nec fabricanda ratis? + Visceribus terræ lateant abstrusa metalla, + Vti opibus nescit quòd mala turba suis? + Quisquis es, aut doctis pareto monentibus, aut te + Inter habere bonos ne fateare locum. + Se non in prærupta metallicus abijcit audax, + Vt quondam immisso Curtius acer equo: + Sed prius ediscit, quæ sunt noscenda perito, + Quodque facit, multa doctus ab arte facit. + Vtque gubernator seruat cum sidere uentos: + Sic minimè dubijs utitur ille notis. + Iasides nauim, currus regit arte Metiscus: + Fossor opus peragit nec minus arte suum. + Indagat uenæ spacium, numerumque, modumque, + Siue obliqua suum, rectaúe tendat iter. + Pastor ut explorat quæ terra sit apta colenti, + Quæ bene lanigeras, quæ malè pascat oues. + En terræ intentus, quid uincula linea tendit? + Fungitur officio iam Ptolemæe tuo. + Vtque suæ inuenit mensuram iuraque uenæ, + In uarios operas diuidit inde uiros. + Iamque aggressus opus, uiden' ut mouet omne quod obstat, + Assidua ut uersat strenuus arma manu? + Ne tibi surdescant ferri tinnitibus aures, + Ad grauiora ideo conspicienda ueni. + Instruit ecce suis nunc artibus ille minores: + Sedulitas nulli non operosa loco. + Metiri docet hic uenæ spaciumque modumque, + Vtque regat positis finibus arua lapis, + Ne quis transmisso uiolentus limite pergens, + Non sibi concessas, in sua uertat, opes. + Hic docet instrumenta, quibus Plutonia regna + Tutus adit, saxi permeat atque uias. + Quanta (uides) solidas expugnet machina terras: + Machina non ullo tempore uisa prius. + Cede nouis, nulla non inclyta laude uetustas, + Posteritas meritis est quoque grata tuis. + Tum quia Germano sunt hæc inuenta sub axe, + Si quis es, inuidiæ contrahe uela tuæ. + Ausonis ora tumet bellis, terra Attica cultu, + Germanum infractus tollit ad astra labor. + Nec tamen ingenio solet infeliciter uti, + Mite gerát Phoebi, seu graue Martis opus, + Tempus adest, structis uenarum montibus, igne + Explorare, usum quem sibi uena ferat, + Non labor ingenio caret hic, non copia fructu, + Est adaperta bonæ prima fenestra spei. + Ergo instat porrò grauiores ferre labores, + Intentas operi nec remouere manus. + Vrere siue locus poscat, seu tundere uerras, + Siue lauare lacu præter euntis aquæ. + Seu flammis iterum modicis torrere necesse est, + Excoquere aut fastis ignibus omne malum, + Cùm fluit æs riuis, auri argentique metallum, + Spes animo fossor uix capit ipse suas. + Argentum cupidus fuluo secernit ab auro, + Et plumbi lentam demit utrique moram. + Separat argentum, lucri studiosus, ab ære, + Seruatis, linquens deteriora, bonis. + Quæ si cuncta uelim tenui percurrere uersu, + Ante alium reuehat Memnonis orta diem. + Postremus labor est, concretos discere succos, + Quos fert innumeris Teutona terra locis. + Quo sal, quo nitrum, quo pacto fiat alumen, + Vsibus artificis cùm parat illa manus: + Nec non chalcantum, sulfur, fluidumque bitumen, + Massaque quo uitri lenta dolanda modo. + Suscipit hæc hominum mirandos cura labores, + Pauperiem usque adeo ferre famemque graue est, + Tantus amor uictum paruis extundere natis, + Et patriæ ciuem non dare uelle malum. + Nec manet in terræ fossoris mersa latebris + Mens, sed fert domino uota precesque Deo. + Munificæ expectat, spe plenus, munera dextræ, + Extollens animum lætus ad astra suum. + Diuitias CHRISTUS dat noticiamque fruendi, + Cui memori grates pectore semper agit. + Hoc quoque laudati quondam fecere Philippi, + Qui uirtutis habent cum pietate decus. + Huc oculos, huc flecte animum, suauissime Lector, + Auctoremque pia noscito mente Deum. + AGRICOLAE hinc optans operoso fausta labori, + Laudibus eximij candidus esto uiri. + Ille suum extollit patriæ cum nomine nomen, + Et uir in ore frequens posteritatis erit. + Cuncta cadunt letho, studij monumenta uigebunt, + Purpurei donec lumina solis erunt. + + Misenæ M. D. LI. + èludo illustri. + + +FOOTNOTES: + +[1] For completeness' sake we reproduce in the original Latin the +laudation of Agricola by his friend, Georgius Fabricius, a leading +scholar of his time. It has but little intrinsic value for it is not +poetry of a very high order, and to make it acceptable English would +require certain improvements, for which only poets have licence. A +"free" translation of the last few lines indicates its complimentary +character:-- + + "He doth raise his country's fame with his own + And in the mouths of nations yet unborn + His praises shall be sung; Death comes to all + But great achievements raise a monument + Which shall endure until the sun grows cold." + + + + + + TO THE MOST ILLUSTRIOUS + AND MOST MIGHTY DUKES OF + Saxony, Landgraves of Thuringia, Margraves of Meissen, + Imperial Overlords of Saxony, Burgraves of Altenberg + and Magdeburg, Counts of Brena, Lords of + Pleissnerland, To MAURICE Grand Marshall + and Elector of the Holy Roman Empire + and to his brother AUGUSTUS,[1] + GEORGE AGRICOLA S. D. + + + + +Most illustrious Princes, often have I considered the metallic arts as a +whole, as Moderatus Columella[2] considered the agricultural arts, just +as if I had been considering the whole of the human body; and when I had +perceived the various parts of the subject, like so many members of the +body, I became afraid that I might die before I should understand its +full extent, much less before I could immortalise it in writing. This +book itself indicates the length and breadth of the subject, and the +number and importance of the sciences of which at least some little +knowledge is necessary to miners. Indeed, the subject of mining is a +very extensive one, and one very difficult to explain; no part of it is +fully dealt with by the Greek and Latin authors whose works survive; and +since the art is one of the most ancient, the most necessary and the +most profitable to mankind, I considered that I ought not to neglect it. +Without doubt, none of the arts is older than agriculture, but that of +the metals is not less ancient; in fact they are at least equal and +coeval, for no mortal man ever tilled a field without implements. In +truth, in all the works of agriculture, as in the other arts, implements +are used which are made from metals, or which could not be made without +the use of metals; for this reason the metals are of the greatest +necessity to man. When an art is so poor that it lacks metals, it is not +of much importance, for nothing is made without tools. Besides, of all +ways whereby great wealth is acquired by good and honest means, none is +more advantageous than mining; for although from fields which are well +tilled (not to mention other things) we derive rich yields, yet we +obtain richer products from mines; in fact, one mine is often much more +beneficial to us than many fields. For this reason we learn from the +history of nearly all ages that very many men have been made rich by the +mines, and the fortunes of many kings have been much amplified thereby. +But I will not now speak more of these matters, because I have dealt +with these subjects partly in the first book of this work, and partly in +the other work entitled _De Veteribus et Novis Metallis_, where I have +refuted the charges which have been made against metals and against +miners. Now, though the art of husbandry, which I willingly rank with +the art of mining, appears to be divided into many branches, yet it is +not separated into so many as this art of ours, nor can I teach the +principles of this as easily as Columella did of that. He had at hand +many writers upon husbandry whom he could follow,--in fact, there are +more than fifty Greek authors whom Marcus Varro enumerates, and more +than ten Latin ones, whom Columella himself mentions. I have only one +whom I can follow; that is C. Plinius Secundus,[3] and he expounds only +a very few methods of digging ores and of making metals. Far from the +whole of the art having been treated by any one writer, those who have +written occasionally on any one or another of its branches have not even +dealt completely with a single one of them. Moreover, there is a great +scarcity even of these, since alone of all the Greeks, Strato of +Lampsacus,[4] the successor of Theophrastus,[5] wrote a book on the +subject, _De Machinis Metallicis_; except, perhaps a work by the poet +Philo, a small part of which embraced to some degree the occupation of +mining.[6] Pherecrates seems to have introduced into his comedy, which +was similar in title, miners as slaves or as persons condemned to serve +in the mines. Of the Latin writers, Pliny, as I have already said, has +described a few methods of working. Also among the authors I must +include the modern writers, whosoever they are, for no one should escape +just condemnation who fails to award due recognition to persons whose +writings he uses, even very slightly. Two books have been written in our +tongue; the one on the assaying of mineral substances and metals, +somewhat confused, whose author is unknown[7]; the other "On Veins," of +which Pandulfus Anglus[8] is also said to have written, although the +German book was written by Calbus of Freiberg, a well-known doctor; but +neither of them accomplished the task he had begun.[9] Recently +Vannucci Biringuccio, of Sienna, a wise man experienced in many matters, +wrote in vernacular Italian on the subject of the melting, separating, +and alloying of metals.[10] He touched briefly on the methods of +smelting certain ores, and explained more fully the methods of making +certain juices; by reading his directions, I have refreshed my memory of +those things which I myself saw in Italy; as for many matters on which I +write, he did not touch upon them at all, or touched but lightly. This +book was given me by Franciscus Badoarius, a Patrician of Venice, and a +man of wisdom and of repute; this he had promised that he would do, when +in the previous year he was at Marienberg, having been sent by the +Venetians as an Ambassador to King Ferdinand. Beyond these books I do +not find any writings on the metallic arts. For that reason, even if the +book of Strato existed, from all these sources not one-half of the whole +body of the science of mining could be pieced together. + +Seeing that there have been so few who have written on the subject of +the metals, it appears to me all the more wonderful that so many +alchemists have arisen who would compound metals artificially, and who +would change one into another. Hermolaus Barbarus,[11] a man of high +rank and station, and distinguished in all kinds of learning, has +mentioned the names of many in his writings; and I will proffer more, +but only famous ones, for I will limit myself to a few. Thus Osthanes +has written on [Greek: chymeutika]; and there are Hermes; Chanes; +Zosimus, the Alexandrian, to his sister Theosebia; Olympiodorus, also an +Alexandrian; Agathodæmon; Democritus, not the one of Abdera, but some +other whom I know not; Orus Chrysorichites, Pebichius, Comerius, +Joannes, Apulejus, Petasius, Pelagius, Africanus, Theophilus, Synesius, +Stephanus to Heracleus Cæsar, Heliodorus to Theodosius, Geber, Callides +Rachaidibus, Veradianus, Rodianus, Canides, Merlin, Raymond Lully, +Arnold de Villa Nova, and Augustinus Pantheus of Venice; and three +women, Cleopatra, the maiden Taphnutia, and Maria the Jewess.[12] All +these alchemists employ obscure language, and Johanes Aurelius +Augurellus of Rimini, alone has used the language of poetry. There are +many other books on this subject, but all are difficult to follow, +because the writers upon these things use strange names, which do not +properly belong to the metals, and because some of them employ now one +name and now another, invented by themselves, though the thing itself +changes not. These masters teach their disciples that the base metals, +when smelted, are broken up; also they teach the methods by which they +reduce them to the primary parts and remove whatever is superfluous in +them, and by supplying what is wanted make out of them the precious +metals--that is, gold and silver,--all of which they carry out in a +crucible. Whether they can do these things or not I cannot decide; but, +seeing that so many writers assure us with all earnestness that they +have reached that goal for which they aimed, it would seem that faith +might be placed in them; yet also seeing that we do not read of any of +them ever having become rich by this art, nor do we now see them growing +rich, although so many nations everywhere have produced, and are +producing, alchemists, and all of them are straining every nerve night +and day to the end that they may heap a great quantity of gold and +silver, I should say the matter is dubious. But although it may be due +to the carelessness of the writers that they have not transmitted to us +the names of the masters who acquired great wealth through this +occupation, certainly it is clear that their disciples either do not +understand their precepts or, if they do understand them, do not follow +them; for if they do comprehend them, seeing that these disciples have +been and are so numerous, they would have by to-day filled whole towns +with gold and silver. Even their books proclaim their vanity, for they +inscribe in them the names of Plato and Aristotle and other +philosophers, in order that such high-sounding inscriptions may impose +upon simple people and pass for learning. There is another class of +alchemists who do not change the substance of base metals, but colour +them to represent gold or silver, so that they appear to be that which +they are not, and when this appearance is taken from them by the fire, +as if it were a garment foreign to them, they return to their own +character. These alchemists, since they deceive people, are not only +held in the greatest odium, but their frauds are a capital offence. No +less a fraud, warranting capital punishment, is committed by a third +sort of alchemists; these throw into a crucible a small piece of gold or +silver hidden in a coal, and after mixing therewith fluxes which have +the power of extracting it, pretend to be making gold from orpiment, or +silver from tin and like substances. But concerning the art of alchemy, +if it be an art, I will speak further elsewhere. I will now return to +the art of mining. + +Since no authors have written of this art in its entirety, and since +foreign nations and races do not understand our tongue, and, if they did +understand it, would be able to learn only a small part of the art +through the works of those authors whom we do possess, I have written +these twelve books _De Re Metallica_. Of these, the first book contains +the arguments which may be used against this art, and against metals and +the mines, and what can be said in their favour. The second book +describes the miner, and branches into a discourse on the finding of +veins. The third book deals with veins and stringers, and seams in the +rocks. The fourth book explains the method of delimiting veins, and also +describes the functions of the mining officials. The fifth book +describes the digging of ore and the surveyor's art. The sixth book +describes the miners' tools and machines. The seventh book is on the +assaying of ore. The eighth book lays down the rules for the work of +roasting, crushing, and washing the ore. The ninth book explains the +methods of smelting ores. The tenth book instructs those who are +studious of the metallic arts in the work of separating silver from +gold, and lead from gold and silver. The eleventh book shows the way of +separating silver from copper. The twelfth book gives us rules for +manufacturing salt, soda, alum, vitriol, sulphur, bitumen, and glass. + +Although I have not fulfilled the task which I have undertaken, on +account of the great magnitude of the subject, I have, at all events, +endeavoured to fulfil it, for I have devoted much labour and care, and +have even gone to some expense upon it; for with regard to the veins, +tools, vessels, sluices, machines, and furnaces, I have not only +described them, but have also hired illustrators to delineate their +forms, lest descriptions which are conveyed by words should either not +be understood by men of our own times, or should cause difficulty to +posterity, in the same way as to us difficulty is often caused by many +names which the Ancients (because such words were familiar to all of +them) have handed down to us without any explanation. + +I have omitted all those things which I have not myself seen, or have +not read or heard of from persons upon whom I can rely. That which I +have neither seen, nor carefully considered after reading or hearing of, +I have not written about. The same rule must be understood with regard +to all my instruction, whether I enjoin things which ought to be done, +or describe things which are usual, or condemn things which are done. +Since the art of mining does not lend itself to elegant language, these +books of mine are correspondingly lacking in refinement of style. The +things dealt with in this art of metals sometimes lack names, either +because they are new, or because, even if they are old, the record of +the names by which they were formerly known has been lost. For this +reason I have been forced by a necessity, for which I must be pardoned, +to describe some of them by a number of words combined, and to +distinguish others by new names,--to which latter class belong +_Ingestor_, _Discretor_, _Lotor_, and _Excoctor_.[13] Other things, +again, I have alluded to by old names, such as the _Cisium_; for when +Nonius Marcellus wrote,[14] this was the name of a two-wheeled vehicle, +but I have adopted it for a small vehicle which has only one wheel; and +if anyone does not approve of these names, let him either find more +appropriate ones for these things, or discover the words used in the +writings of the Ancients. + +These books, most illustrious Princes, are dedicated to you for many +reasons, and, above all others, because metals have proved of the +greatest value to you; for though your ancestors drew rich profits from +the revenues of their vast and wealthy territories, and likewise from +the taxes which were paid by the foreigners by way of toll and by the +natives by way of tithes, yet they drew far richer profits from the +mines. Because of the mines not a few towns have risen into eminence, +such as Freiberg, Annaberg, Marienberg, Schneeberg, Geyer, and +Altenberg, not to mention others. Nay, if I understand anything, greater +wealth now lies hidden beneath the ground in the mountainous parts of +your territory than is visible and apparent above ground. Farewell. + + _Chemnitz, Saxony, + December First, 1550._ + + +FOOTNOTES: + +[1] For Agricola's relations with these princes see p. ix. + +[2] Lucius Junius Moderatus Columella was a Roman, a native of Cadiz, +and lived during the 1st Century. He was the author of _De Re Rustica_ +in 12 books. It was first printed in 1472, and some fifteen or sixteen +editions had been printed before Agricola's death. + +[3] We give a short review of Pliny's _Naturalis Historia_ in the +Appendix B. + +[4] This work is not extant, as Agricola duly notes later on. Strato +succeeded Theophrastus as president of the Lyceum, 288 B.C. + +[5] For note on Theophrastus see Appendix B. + +[6] It appears that the poet Philo did write a work on mining which is +not extant. So far as we know the only reference to this work is in +Athenæus' (200 A.D.) _Deipnosophistae_. The passage as it appears in C. +D. Yonge's Translation (Bonn's Library, London, 1854, Vol. II, Book VII, +p. 506) is: "And there is a similar fish produced in the Red Sea which +is called Stromateus; it has gold-coloured lines running along the whole +of his body, as Philo tells us in his book on Mines." There is a +fragment of a poem of Pherecrates, entitled "Miners," but it seems to +have little to do with mining. + +[7] The title given by Agricola _De Materiae Metallicae et Metallorum +Experimento_ is difficult to identify. It seems likely to be the little +_Probier Büchlein_, numbers of which were published in German in the +first half of the 16th Century. We discuss this work at some length in +the Appendix B on Ancient Authors. + +[8] Pandulfus, "the Englishman," is mentioned by various 15th and 16th +Century writers, and in the preface of Mathias Farinator's _Liber +Moralitatum ... Rerum Naturalium_, etc., printed in Augsburg, 1477, +there is a list of books among which appears a reference to a work by +Pandulfus on veins and minerals. We have not been able to find the book. + +[9] Jacobi (_Der Mineralog Georgius Agricola_, Zwickau, 1881, p. 47) +says: "Calbus Freibergius, so called by Agricola himself, is certainly +no other than the Freiberg Doctor Rühlein von Kalbe; he was, according +to Möller, a doctor and burgomaster at Freiberg at the end of the 15th +and the beginning of the 16th Centuries.... The chronicler describes him +as a fine mathematician, who helped to survey and design the mining +towns of Annaberg in 1497 and Marienberg in 1521." We would call +attention to the statement of Calbus' views, quoted at the end of Book +III, _De Re Metallica_ (p. 75), which are astonishingly similar to +statements in the _Nützlich Bergbüchlin_, and leave little doubt that +this "Calbus" was the author of that anonymous book on veins. For +further discussion see Appendix B. + +[10] For discussion of Biringuccio see Appendix B. The proper title is +_De La Pirotechnia_ (Venice, 1540). + +[11] Hermolaus Barbarus, according to Watt (_Bibliotheca Britannica_, +London, 1824), was a lecturer on Philosophy in Padua. He was born in +1454, died in 1493, and was the author of a number of works on medicine, +natural history, etc., with commentaries on the older authors. + +[12] The debt which humanity does owe to these self-styled philosophers +must not be overlooked, for the science of Chemistry comes from three +sources--Alchemy, Medicine and Metallurgy. However polluted the former +of these may be, still the vast advance which it made by the discovery +of the principal acids, alkalis, and the more common of their salts, +should be constantly recognized. It is obviously impossible, within the +space of a footnote, to give anything but the most casual notes as to +the personages here mentioned and their writings. Aside from the +classics and religious works, the libraries of the Middle Ages teemed +with more material on Alchemy than on any other one subject, and since +that date a never-ending stream of historical, critical, and discursive +volumes and tracts devoted to the old Alchemists and their writings has +been poured upon the world. A collection recently sold in London, +relating to Paracelsus alone, embraced over seven hundred volumes. + +Of many of the Alchemists mentioned by Agricola little is really known, +and no two critics agree as to the commonest details regarding many of +them; in fact, an endless confusion springs from the negligent habit of +the lesser Alchemists of attributing the authorship of their writings to +more esteemed members of their own ilk, such as Hermes, Osthanes, etc., +not to mention the palpable spuriousness of works under the names of the +real philosophers, such as Aristotle, Plato, or Moses, and even of Jesus +Christ. Knowledge of many of the authors mentioned by Agricola does not +extend beyond the fact that the names mentioned are appended to various +writings, in some instances to MSS yet unpublished. They may have been +actual persons, or they may not. Agricola undoubtedly had perused such +manuscripts and books in some leading library, as the quotation from +Boerhaave given later shows. Shaw (A New Method of Chemistry, etc., +London, 1753. Vol. I, p. 25) considers that the large number of such +manuscripts in the European libraries at this time were composed or +transcribed by monks and others living in Constantinople, Alexandria, +and Athens, who fled westward before the Turkish invasion, bringing +their works with them. + +For purposes of this summary we group the names mentioned by Agricola, +the first class being of those who are known only as names appended to +MSS or not identifiable at all. Possibly a more devoted student of the +history of Alchemy would assign fewer names to this department of +oblivion. They are Maria the Jewess, Orus Chrysorichites, Chanes, +Petasius, Pebichius, Theophilus, Callides, Veradianus, Rodianus, +Canides, the maiden Taphnutia, Johannes, Augustinus, and Africanus. The +last three are names so common as not to be possible of identification +without more particulars, though Johannes may be the Johannes Rupeseissa +(1375), an alchemist of some note. Many of these names can be found +among the Bishops and Prelates of the early Christian Church, but we +doubt if their owners would ever be identified with such indiscretions +as open, avowed alchemy. The Theophilus mentioned might be the +metal-working monk of the 12th Century, who is further discussed in +Appendix B on Ancient Authors. + +In the next group fall certain names such as Osthanes, Hermes, Zosimus, +Agathodaemon, and Democritus, which have been the watchwords of +authority to Alchemists of all ages. These certainly possessed the great +secrets, either the philosopher's stone or the elixir. Hermes +Trismegistos was a legendary Egyptian personage supposed to have +flourished before 1,500 B.C., and by some considered to be a corruption +of the god Thoth. He is supposed to have written a number of works, but +those extant have been demonstrated to date not prior to the second +Century; he is referred to by the later Greek Alchemists, and was +believed to have possessed the secret of transmutation. Osthanes was +also a very shadowy personage, and was considered by some Alchemists to +have been an Egyptian prior to Hermes, by others to have been the +teacher of Zoroaster. Pliny mentions a magician of this name who +accompanied Xerxes' army. Later there are many others of this name, and +the most probable explanation is that this was a favourite pseudonym for +ancient magicians; there is a very old work, of no great interest, in +MSS in Latin and Greek, in the Munich, Gotha, Vienna, and other +libraries, by one of this name. Agathodaemon was still another shadowy +character referred to by the older Alchemists. There are MSS in the +Florence, Paris, Escurial, and Munich libraries bearing his name, but +nothing tangible is known as to whether he was an actual man or if these +writings are not of a much later period than claimed. + +To the next group belong the Greek Alchemists, who flourished during the +rise and decline of Alexandria, from 200 B.C. to 700 A.D., and we give +them in order of their dates. Comerius was considered by his later +fellow professionals to have been the teacher of the art to Cleopatra +(1st Century B.C.), and a MSS with a title to that effect exists in the +Bibliothèque Nationale at Paris. The celebrated Cleopatra seems to have +stood very high in the estimation of the Alchemists; perhaps her +doubtful character found a response among them; there are various works +extant in MSS attributed to her, but nothing can be known as to their +authenticity. Lucius Apulejus or Apuleius was born in Numidia about the +2nd Century; he was a Roman Platonic Philosopher, and was the author of +a romance, "The Metamorphosis, or the Golden Ass." Synesius was a Greek, +but of unknown period; there is a MSS treatise on the Philosopher's +Stone in the library at Leyden under his name, and various printed works +are attributed to him; he mentions "water of saltpetre," and has, +therefore, been hazarded to be the earliest recorder of nitric acid. The +work here referred to as "Heliodorus to Theodosius" was probably the MSS +in the Libraries at Paris, Vienna, Munich, etc., under the title of +"Heliodorus the Philosopher's Poem to the Emperor Theodosius the Great +on the Mystic Art of the Philosophers, etc." His period would, +therefore, be about the 4th Century. The Alexandrian Zosimus is more +generally known as Zosimus the Panopolite, from Panopolis, an ancient +town on the Nile; he flourished in the 5th Century, and belonged to the +Alexandrian School of Alchemists; he should not be confused with the +Roman historian of the same name and period. The following statement is +by Boerhaave (_Elementa Chemiae_, Paris, 1724, Chap. I.):--"The name +Chemistry written in Greek, or _Chemia_, is so ancient as perhaps to +have been used in the antediluvian age. Of this opinion was Zosimus the +Panopolite, whose Greek writings, though known as long as before the +year 1550 to George Agricola, and afterwards perused ... by Jas. +Scaliger and Olaus Borrichius, still remain unpublished in the King of +France's library. In one of these, entitled, 'The Instruction of Zosimus +the Panopolite and Philosopher, out of those written to Theosebia, +etc....'" Olympiodorus was an Alexandrian of the 5th Century, whose +writings were largely commentaries on Plato and Aristotle; he is +sometimes accredited with being the first to describe white arsenic +(arsenical oxide). The full title of the work styled "Stephanus to +Heracleus Caesar," as published in Latin at Padua in 1573, was "Stephan +of Alexandria, the Universal Philosopher and Master, his nine processes +on the great art of making gold and silver, addressed to the Emperor +Heraclius." He, therefore, if authentic, dates in the 7th Century. + +To the next class belong those of the Middle Ages, which we give in +order of date. The works attributed to Geber play such an important part +in the history of Chemistry and Metallurgy that we discuss his book at +length in Appendix B. Late criticism indicates that this work was not +the production of an 8th Century Arab, but a compilation of some Latin +scholar of the 12th or 13th Centuries. Arnold de Villa Nova, born about +1240, died in 1313, was celebrated as a physician, philosopher, and +chemist; his first works were published in Lyons in 1504; many of them +have apparently never been printed, for references may be found to some +18 different works. Raymond Lully, a Spaniard, born in 1235, who was a +disciple of Arnold de Villa Nova, was stoned to death in Africa in 1315. +There are extant over 100 works attributed to this author, although +again the habit of disciples of writing under the master's name may be +responsible for most of these. John Aurelio Augurello was an Italian +Classicist, born in Rimini about 1453. The work referred to, +_Chrysopoeia et Gerontica_ is a poem on the art of making gold, etc., +published in Venice, 1515, and re-published frequently thereafter; it is +much quoted by Alchemists. With regard to Merlin, as satisfactory an +account as any of this truly English magician may be found in Mark +Twain's "Yankee at the Court of King Arthur." It is of some interest to +note that Agricola omits from his list Avicenna (980-1037 A.D.), Roger +Bacon (1214-1294), Albertus Magnus (1193-1280), Basil Valentine (end +15th century?), and Paracelsus, a contemporary of his own. In _De Ortu +et Causis_ he expends much thought on refutation of theories advanced by +Avicenna and Albertus, but of the others we have found no mention, +although their work is, from a chemical point of view, of considerable +importance. + +[13] _Ingestor_,--Carrier; _Discretor_,--Sorter; _Lotor_,--Washer; +_Excoctor_,--Smelter. + +[14] Nonius Marcellus was a Roman grammarian of the 4th Century B.C. His +extant treatise is entitled, _De Compendiosa Doctrina per Litteras ad +Filium_. + + + + +BOOK I. + + +Many persons hold the opinion that the metal industries are fortuitous +and that the occupation is one of sordid toil, and altogether a kind of +business requiring not so much skill as labour. But as for myself, when +I reflect carefully upon its special points one by one, it appears to be +far otherwise. For a miner must have the greatest skill in his work, +that he may know first of all what mountain or hill, what valley or +plain, can be prospected most profitably, or what he should leave alone; +moreover, he must understand the veins, stringers[1] and seams in the +rocks[2]. Then he must be thoroughly familiar with the many and varied +species of earths, juices[3], gems, stones, marbles, rocks, metals, and +compounds[4]. He must also have a complete knowledge of the method of +making all underground works. Lastly, there are the various systems of +assaying[5] substances and of preparing them for smelting; and here +again there are many altogether diverse methods. For there is one method +for gold and silver, another for copper, another for quicksilver, +another for iron, another for lead, and even tin and bismuth[6] are +treated differently from lead. Although the evaporation of juices is an +art apparently quite distinct from metallurgy, yet they ought not to be +considered separately, inasmuch as these juices are also often dug out +of the ground solidified, or they are produced from certain kinds of +earth and stones which the miners dig up, and some of the juices are not +themselves devoid of metals. Again, their treatment is not simple, since +there is one method for common salt, another for soda[7], another for +alum, another for vitriol[8], another for sulphur, and another for +bitumen. + +Furthermore, there are many arts and sciences of which a miner should +not be ignorant. First there is Philosophy, that he may discern the +origin, cause, and nature of subterranean things; for then he will be +able to dig out the veins easily and advantageously, and to obtain more +abundant results from his mining. Secondly, there is Medicine, that he +may be able to look after his diggers and other workmen, that they do +not meet with those diseases to which they are more liable than workmen +in other occupations, or if they do meet with them, that he himself may +be able to heal them or may see that the doctors do so. Thirdly follows +Astronomy, that he may know the divisions of the heavens and from them +judge the direction of the veins. Fourthly, there is the science of +Surveying that he may be able to estimate how deep a shaft should be +sunk to reach the tunnel which is being driven to it, and to determine +the limits and boundaries in these workings, especially in depth. +Fifthly, his knowledge of Arithmetical Science should be such that he +may calculate the cost to be incurred in the machinery and the working +of the mine. Sixthly, his learning must comprise Architecture, that he +himself may construct the various machines and timber work required +underground, or that he may be able to explain the method of the +construction to others. Next, he must have knowledge of Drawing, that he +can draw plans of his machinery. Lastly, there is the Law, especially +that dealing with metals, that he may claim his own rights, that he may +undertake the duty of giving others his opinion on legal matters, that +he may not take another man's property and so make trouble for himself, +and that he may fulfil his obligations to others according to the law. + +It is therefore necessary that those who take an interest in the methods +and precepts of mining and metallurgy should read these and others of +our books studiously and diligently; or on every point they should +consult expert mining people, though they will discover few who are +skilled in the whole art. As a rule one man understands only the methods +of mining, another possesses the knowledge of washing[9], another is +experienced in the art of smelting, another has a knowledge of measuring +the hidden parts of the earth, another is skilful in the art of making +machines, and finally, another is learned in mining law. But as for us, +though we may not have perfected the whole art of the discovery and +preparation of metals, at least we can be of great assistance to persons +studious in its acquisition. + +But let us now approach the subject we have undertaken. Since there has +always been the greatest disagreement amongst men concerning metals and +mining, some praising, others utterly condemning them, therefore I have +decided that before imparting my instruction, I should carefully weigh +the facts with a view to discovering the truth in this matter. + +So I may begin with the question of utility, which is a two-fold one, +for either it may be asked whether the art of mining is really +profitable or not to those who are engaged in it, or whether it is +useful or not to the rest of mankind. Those who think mining of no +advantage to the men who follow the occupation assert, first, that +scarcely one in a hundred who dig metals or other such things derive +profit therefrom; and again, that miners, because they entrust their +certain and well-established wealth to dubious and slippery fortune, +generally deceive themselves, and as a result, impoverished by expenses +and losses, in the end spend the most bitter and most miserable of +lives. But persons who hold these views do not perceive how much a +learned and experienced miner differs from one ignorant and unskilled in +the art. The latter digs out the ore without any careful discrimination, +while the former first assays and proves it, and when he finds the veins +either too narrow and hard, or too wide and soft, he infers therefrom +that these cannot be mined profitably, and so works only the approved +ones. What wonder then if we find the incompetent miner suffers loss, +while the competent one is rewarded by an abundant return from his +mining? The same thing applies to husbandmen. For those who cultivate +land which is alike arid, heavy, and barren, and in which they sow +seeds, do not make so great a harvest as those who cultivate a fertile +and mellow soil and sow their grain in that. And since by far the +greater number of miners are unskilled rather than skilled in the art, +it follows that mining is a profitable occupation to very few men, and a +source of loss to many more. Therefore the mass of miners who are quite +unskilled and ignorant in the knowledge of veins not infrequently lose +both time and trouble[10]. Such men are accustomed for the most part to +take to mining, either when through being weighted with the fetters of +large and heavy debts, they have abandoned a business, or desiring to +change their occupation, have left the reaping-hook and plough; and so +if at any time such a man discovers rich veins or other abounding mining +produce, this occurs more by good luck than through any knowledge on his +part. We learn from history that mining has brought wealth to many, for +from old writings it is well known that prosperous Republics, not a few +kings, and many private persons, have made fortunes through mines and +their produce. This subject, by the use of many clear and illustrious +examples, I have dilated upon and explained in the first Book of my work +entitled "_De Veteribus et Novis Metallis_," from which it is evident +that mining is very profitable to those who give it care and attention. + +Again, those who condemn the mining industry say that it is not in the +least stable, and they glorify agriculture beyond measure. But I do not +see how they can say this with truth, for the silver mines at Freiberg +in Meissen remain still unexhausted after 400 years, and the lead mines +of Goslar after 600 years. The proof of this can be found in the +monuments of history. The gold and silver mines belonging to the +communities of Schemnitz and Cremnitz have been worked for 800 years, +and these latter are said to be the most ancient privileges of the +inhabitants. Some then say the profit from an individual mine is +unstable, as if forsooth, the miner is, or ought to be dependent on only +one mine, and as if many men do not bear in common their expenses in +mining, or as if one experienced in his art does not dig another vein, +if fortune does not amply respond to his prayers in the first case. The +New Schönberg at Freiberg has remained stable beyond the memory of +man[11]. + +It is not my intention to detract anything from the dignity of +agriculture, and that the profits of mining are less stable I will +always and readily admit, for the veins do in time cease to yield +metals, whereas the fields bring forth fruits every year. But though the +business of mining may be less reliable it is more productive, so that +in reckoning up, what is wanting in stability is found to be made up by +productiveness. Indeed, the yearly profit of a lead mine in comparison +with the fruitfulness of the best fields, is three times or at least +twice as great. How much does the profit from gold or silver mines +exceed that earned from agriculture? Wherefore truly and shrewdly does +Xenophon[12] write about the Athenian silver mines: "There is land of +such a nature that if you sow, it does not yield crops, but if you dig, +it nourishes many more than if it had borne fruit." So let the farmers +have for themselves the fruitful fields and cultivate the fertile hills +for the sake of their produce; but let them leave to miners the gloomy +valleys and sterile mountains, that they may draw forth from these, gems +and metals which can buy, not only the crops, but all things that are +sold. + +The critics say further that mining is a perilous occupation to pursue, +because the miners are sometimes killed by the pestilential air which +they breathe; sometimes their lungs rot away; sometimes the men perish +by being crushed in masses of rock; sometimes, falling from the ladders +into the shafts, they break their arms, legs, or necks; and it is added +there is no compensation which should be thought great enough to +equalize the extreme dangers to safety and life. These occurrences, I +confess, are of exceeding gravity, and moreover, fraught with terror and +peril, so that I should consider that the metals should not be dug up at +all, if such things were to happen very frequently to the miners, or if +they could not safely guard against such risks by any means. Who would +not prefer to live rather than to possess all things, even the metals? +For he who thus perishes possesses nothing, but relinquishes all to his +heirs. But since things like this rarely happen, and only in so far as +workmen are careless, they do not deter miners from carrying on their +trade any more than it would deter a carpenter from his, because one of +his mates has acted incautiously and lost his life by falling from a +high building. I have thus answered each argument which critics are wont +to put before me when they assert that mining is an undesirable +occupation, because it involves expense with uncertainty of return, +because it is changeable, and because it is dangerous to those engaged +in it. + +Now I come to those critics who say that mining is not useful to the +rest of mankind because forsooth, gems, metals, and other mineral +products are worthless in themselves. This admission they try to extort +from us, partly by arguments and examples, partly by misrepresentations +and abuse of us. First, they make use of this argument: "The earth does +not conceal and remove from our eyes those things which are useful and +necessary to mankind, but on the contrary, like a beneficent and kindly +mother she yields in large abundance from her bounty and brings into the +light of day the herbs, vegetables, grains, and fruits, and the trees. +The minerals on the other hand she buries far beneath in the depth of +the ground; therefore, they should not be sought. But they are dug out +by wicked men who, as the poets say, are the products of the Iron Age." +Ovid censures their audacity in the following lines:-- + + "And not only was the rich soil required to furnish corn and + due sustenance, but men even descended into the entrails of the + earth, and they dug up riches, those incentives to vice, which + the earth had hidden and had removed to the Stygian shades. + Then destructive iron came forth, and gold, more destructive + than iron; then war came forth."[13] + +Another of their arguments is this: Metals offer to men no advantages, +therefore we ought not to search them out. For whereas man is composed +of soul and body, neither is in want of minerals. The sweetest food of +the soul is the contemplation of nature, a knowledge of the finest arts +and sciences, an understanding of virtue; and if he interests his mind +in excellent things, if he exercise his body, he will be satisfied with +this feast of noble thoughts and knowledge, and have no desire for other +things. Now although the human body may be content with necessary food +and clothing, yet the fruits of the earth and the animals of different +kinds supply him in wonderful abundance with food and drink, from which +the body may be suitably nourished and strengthened and life prolonged +to old age. Flax, wool, and the skins of many animals provide plentiful +clothing low in price; while a luxurious kind, not hard to procure--that +is the so called _seric_ material, is furnished by the down of trees and +the webs of the silk worm. So that the body has absolutely no need of +the metals, so hidden in the depths of the earth and for the greater +part very expensive. Wherefore it is said that this maxim of Euripides +is approved in assemblies of learned men, and with good reason was +always on the lips of Socrates: + + "Works of silver and purple are of use, not for human life, but + rather for Tragedians."[14] + +These critics praise also this saying from Timocreon of Rhodes: + + "O Unseeing Plutus, would that thou hadst never appeared in the + earth or in the sea or on the land, but that thou didst have + thy habitation in Tartarus and Acheron, for out of thee arise + all evil things which overtake mankind"[15]. + +They greatly extol these lines from Phocylides: + + "Gold and silver are injurious to mortals; gold is the source + of crime, the plague of life, and the ruin of all things. Would + that thou were not such an attractive scourge! because of thee + arise robberies, homicides, warfare, brothers are maddened + against brothers, and children against parents." + +This from Naumachius also pleases them: + + "Gold and silver are but dust, like the stones that lie + scattered on the pebbly beach, or on the margins of the + rivers." + +On the other hand, they censure these verses of Euripides: + + "Plutus is the god for wise men; all else is mere folly and at + the same time a deception in words." + +So in like manner these lines from Theognis: + + "O Plutus, thou most beautiful and placid god! whilst I have + thee, however bad I am, I can be regarded as good." + +They also blame Aristodemus, the Spartan, for these words: + + "Money makes the man; no one who is poor is either good or + honoured." + +And they rebuke these songs of Timocles: + + "Money is the life and soul of mortal men. He who has not + heaped up riches for himself wanders like a dead man amongst + the living." + +Finally, they blame Menander when he wrote: + + "Epicharmus asserts that the gods are water, wind, fire, earth, + sun, and stars. But I am of opinion that the gods of any use to + us are silver and gold; for if thou wilt set these up in thy + house thou mayest seek whatever thou wilt. All things will fall + to thy lot; land, houses, slaves, silver-work; moreover + friends, judges, and witnesses. Only give freely, for thus thou + hast the gods to serve thee." + +But besides this, the strongest argument of the detractors is that the +fields are devastated by mining operations, for which reason formerly +Italians were warned by law that no one should dig the earth for metals +and so injure their very fertile fields, their vineyards, and their +olive groves. Also they argue that the woods and groves are cut down, +for there is need of an endless amount of wood for timbers, machines, +and the smelting of metals. And when the woods and groves are felled, +then are exterminated the beasts and birds, very many of which furnish a +pleasant and agreeable food for man. Further, when the ores are washed, +the water which has been used poisons the brooks and streams, and either +destroys the fish or drives them away. Therefore the inhabitants of +these regions, on account of the devastation of their fields, woods, +groves, brooks and rivers, find great difficulty in procuring the +necessaries of life, and by reason of the destruction of the timber they +are forced to greater expense in erecting buildings. Thus it is said, it +is clear to all that there is greater detriment from mining than the +value of the metals which the mining produces. + +So in fierce contention they clamour, showing by such examples as follow +that every great man has been content with virtue, and despised metals. +They praise Bias because he esteemed the metals merely as fortune's +playthings, not as his real wealth. When his enemies had captured his +native Priene, and his fellow-citizens laden with precious things had +betaken themselves to flight, he was asked by one, why he carried away +none of his goods with him, and he replied, "I carry all my possessions +with me." And it is said that Socrates, having received twenty minae +sent to him by Aristippus, a grateful disciple, refused them and sent +them back to him by the command of his conscience. Aristippus, following +his example in this matter, despised gold and regarded it as of no +value. And once when he was making a journey with his slaves, and they, +laden with the gold, went too slowly, he ordered them to keep only as +much of it as they could carry without distress and to throw away the +remainder[16]. Moreover, Anacreon of Teos, an ancient and noble poet, +because he had been troubled about them for two nights, returned five +talents which had been given him by Polycrates, saying that they were +not worth the anxiety which he had gone through on their account. In +like manner celebrated and exceedingly powerful princes have imitated +the philosophers in their scorn and contempt for gold and silver. There +was for example, Phocion, the Athenian, who was appointed general of the +army so many times, and who, when a large sum of gold was sent to him as +a gift by Alexander, King of Macedon, deemed it trifling and scorned it. +And Marcus Curius ordered the gold to be carried back to the Samnites, +as did also Fabricius Luscinus with regard to the silver and copper. And +certain Republics have forbidden their citizens the use and employment +of gold and silver by law and ordinance; the Lacedaemonians, by the +decrees and ordinances of Lycurgus, used diligently to enquire among +their citizens whether they possessed any of these things or not, and +the possessor, when he was caught, was punished according to law and +justice. The inhabitants of a town on the Tigris, called Babytace, +buried their gold in the ground so that no one should use it. The +Scythians condemned the use of gold and silver so that they might not +become avaricious. + +Further are the metals reviled; in the first place people wantonly abuse +gold and silver and call them deadly and nefarious pests of the human +race, because those who possess them are in the greatest peril, for +those who have none lay snares for the possessors of wealth, and thus +again and again the metals have been the cause of destruction and ruin. +For example, Polymnestor, King of Thrace, to obtain possession of his +gold, killed Polydorus, his noble guest and the son of Priam, his +father-in-law, and old friend. Pygmalion, the King of Tyre, in order +that he might seize treasures of gold and silver, killed his sister's +husband, a priest, taking no account of either kinship or religion. For +love of gold Eriphyle betrayed her husband Amphiaraus to his enemy. +Likewise Lasthenes betrayed the city of Olynthus to Philip of Macedon. +The daughter of Spurius Tarpeius, having been bribed with gold, admitted +the Sabines into the citadel of Rome. Claudius Curio sold his country +for gold to Cæsar, the Dictator. Gold, too, was the cause of the +downfall of Aesculapius, the great physician, who it was believed was +the son of Apollo. Similarly Marcus Crassus, through his eager desire +for the gold of the Parthians, was completely overcome together with his +son and eleven legions, and became the jest of his enemies; for they +poured liquid gold into the gaping mouth of the slain Crassus, saying: +"Thou hast thirsted for gold, therefore drink gold." + +But why need I cite here these many examples from history?[17] It is +almost our daily experience to learn that, for the sake of obtaining +gold and silver, doors are burst open, walls are pierced, wretched +travellers are struck down by rapacious and cruel men born to theft, +sacrilege, invasion, and robbery. We see thieves seized and strung up +before us, sacrilegious persons burnt alive, the limbs of robbers broken +on the wheel, wars waged for the same reason, which are not only +destructive to those against whom they are waged, but to those also who +carry them on. Nay, but they say that the precious metals foster all +manner of vice, such as the seduction of women, adultery, and +unchastity, in short, crimes of violence against the person. Therefore +the Poets, when they represent Jove transformed into a golden shower and +falling into the lap of Danae, merely mean that he had found for himself +a safe road by the use of gold, by which he might enter the tower for +the purpose of violating the maiden. Moreover, the fidelity of many men +is overthrown by the love of gold and silver, judicial sentences are +bought, and innumerable crimes are perpetrated. For truly, as Propertius +says: + + "This is indeed the Golden Age. The greatest rewards come from + gold; by gold love is won; by gold is faith destroyed; by gold + is justice bought; the law follows the track of gold, while + modesty will soon follow it when law is gone." + +Diphilus says: + + "I consider that nothing is more powerful than gold. By it all + things are torn asunder; all things are accomplished." + +Therefore, all the noblest and best despise these riches, deservedly and +with justice, and esteem them as nothing. And this is said by the old +man in Plautus: + + "I hate gold. It has often impelled many people to many wrong + acts." + +In this country too, the poets inveigh with stinging reproaches against +money coined from gold and silver. And especially did Juvenal: + + "Since the majesty of wealth is the most sacred thing among us; + although, O pernicious money, thou dost not yet inhabit a + temple, nor have we erected altars to money." + +And in another place: + + "Demoralising money first introduced foreign customs, and + voluptuous wealth weakened our race with disgraceful + luxury."[18] + +And very many vehemently praise the barter system which men used before +money was devised, and which even now obtains among certain simple +peoples. + +And next they raise a great outcry against other metals, as iron, than +which they say nothing more pernicious could have been brought into the +life of man. For it is employed in making swords, javelins, spears, +pikes, arrows--weapons by which men are wounded, and which cause +slaughter, robbery, and wars. These things so moved the wrath of Pliny +that he wrote: "Iron is used not only in hand to hand fighting, but also +to form the winged missiles of war, sometimes for hurling engines, +sometimes for lances, sometimes even for arrows. I look upon it as the +most deadly fruit of human ingenuity. For to bring Death to men more +quickly we have given wings to iron and taught it to fly."[19] The +spear, the arrow from the bow, or the bolt from the catapult and other +engines can be driven into the body of only one man, while the iron +cannon-ball fired through the air, can go through the bodies of many +men, and there is no marble or stone object so hard that it cannot be +shattered by the force and shock. Therefore it levels the highest towers +to the ground, shatters and destroys the strongest walls. Certainly the +ballistas which throw stones, the battering rams and other ancient war +engines for making breaches in walls of fortresses and hurling down +strongholds, seem to have little power in comparison with our present +cannon. These emit horrible sounds and noises, not less than thunder, +flashes of fire burst from them like the lightning, striking, crushing, +and shattering buildings, belching forth flames and kindling fires even +as lightning flashes. So that with more justice could it be said of the +impious men of our age than of Salmoneus of ancient days, that they had +snatched lightning from Jupiter and wrested it from his hands. Nay, +rather there has been sent from the infernal regions to the earth this +force for the destruction of men, so that Death may snatch to himself as +many as possible by one stroke. + +But because muskets are nowadays rarely made of iron, and the large ones +never, but of a certain mixture of copper and tin, they confer more +maledictions on copper and tin than on iron. In this connection too, +they mention the brazen bull of Phalaris, the brazen ox of the people of +Pergamus, racks in the shape of an iron dog or a horse, manacles, +shackles, wedges, hooks, and red-hot plates. Cruelly racked by such +instruments, people are driven to confess crimes and misdeeds which they +have never committed, and innocent men are miserably tortured to death +by every conceivable kind of torment. + +It is claimed too, that lead is a pestilential and noxious metal, for +men are punished by means of molten lead, as Horace describes in the ode +addressed to the Goddess Fortune: "Cruel Necessity ever goes before thee +bearing in her brazen hand the spikes and wedges, while the awful hook +and molten lead are also not lacking."[20] In their desire to excite +greater odium for this metal, they are not silent about the leaden balls +of muskets, and they find in it the cause of wounds and death. + +They contend that, inasmuch as Nature has concealed metals far within +the depths of the earth, and because they are not necessary to human +life, they are therefore despised and repudiated by the noblest, and +should not be mined, and seeing that when brought to light they have +always proved the cause of very great evils, it follows that mining is +not useful to mankind, but on the contrary harmful and destructive. +Several good men have been so perturbed by these tragedies that they +conceive an intensely bitter hatred toward metals, and they wish +absolutely that metals had never been created, or being created, that no +one had ever dug them out. The more I commend the singular honesty, +innocence, and goodness of such men, the more anxious shall I be to +remove utterly and eradicate all error from their minds and to reveal +the sound view, which is that the metals are most useful to mankind. + +In the first place then, those who speak ill of the metals and refuse to +make use of them, do not see that they accuse and condemn as wicked the +Creator Himself, when they assert that He fashioned some things vainly +and without good cause, and thus they regard Him as the Author of evils, +which opinion is certainly not worthy of pious and sensible men. + +In the next place, the earth does not conceal metals in her depths +because she does not wish that men should dig them out, but because +provident and sagacious Nature has appointed for each thing its place. +She generates them in the veins, stringers, and seams in the rocks, as +though in special vessels and receptacles for such material. The metals +cannot be produced in the other elements because the materials for their +formation are wanting. For if they were generated in the air, a thing +that rarely happens, they could not find a firm resting-place, but by +their own force and weight would settle down on to the ground. Seeing +then that metals have their proper abiding place in the bowels of the +earth, who does not see that these men do not reach their conclusions by +good logic? + +They say, "Although metals are in the earth, each located in its own +proper place where it originated, yet because they lie thus enclosed and +hidden from sight, they should not be taken out." But, in refutation of +these attacks, which are so annoying, I will on behalf of the metals +instance the fish, which we catch, hidden and concealed though they be +in the water, even in the sea. Indeed, it is far stranger that man, a +terrestrial animal, should search the interior of the sea than the +bowels of the earth. For as birds are born to fly freely through the +air, so are fishes born to swim through the waters, while to other +creatures Nature has given the earth that they might live in it, and +particularly to man that he might cultivate it and draw out of its +caverns metals and other mineral products. On the other hand, they say +that we eat fish, but neither hunger nor thirst is dispelled by +minerals, nor are they useful in clothing the body, which is another +argument by which these people strive to prove that metals should not be +taken out. But man without metals cannot provide those things which he +needs for food and clothing. For, though the produce of the land +furnishes the greatest abundance of food for the nourishment of our +bodies, no labour can be carried on and completed without tools. The +ground itself is turned up with ploughshares and harrows, tough stalks +and the tops of the roots are broken off and dug up with a mattock, the +sown seed is harrowed, the corn field is hoed and weeded; the ripe +grain with part of the stalk is cut down by scythes and threshed on the +floor, or its ears are cut off and stored in the barn and later beaten +with flails and winnowed with fans, until finally the pure grain is +stored in the granary, whence it is brought forth again when occasion +demands or necessity arises. Again, if we wish to procure better and +more productive fruits from trees and bushes, we must resort to +cultivating, pruning, and grafting, which cannot be done without tools. +Even as without vessels we cannot keep or hold liquids, such as milk, +honey, wine, or oil, neither could so many living things be cared for +without buildings to protect them from long-continued rain and +intolerable cold. Most of the rustic instruments are made of iron, as +ploughshares, share-beams, mattocks, the prongs of harrows, hoes, +planes, hay-forks, straw cutters, pruning shears, pruning hooks, spades, +lances, forks, and weed cutters. Vessels are also made of copper or +lead. Neither are wooden instruments or vessels made without iron. Wine +cellars, oil-mills, stables, or any other part of a farm building could +not be built without iron tools. Then if the bull, the wether, the goat, +or any other domestic animal is led away from the pasture to the +butcher, or if the poulterer brings from the farm a chicken, a hen, or a +capon for the cook, could any of these animals be cut up and divided +without axes and knives? I need say nothing here about bronze and copper +pots for cooking, because for these purposes one could make use of +earthen vessels, but even these in turn could not be made and fashioned +by the potter without tools, for no instruments can be made out of wood +alone, without the use of iron. Furthermore, hunting, fowling, and +fishing supply man with food, but when the stag has been ensnared does +not the hunter transfix him with his spear? As he stands or runs, does +he not pierce him with an arrow? Or pierce him with a bullet? Does not +the fowler in the same way kill the moor-fowl or pheasant with an arrow? +Or does he not discharge into its body the ball from the musket? I will +not speak of the snares and other instruments with which the woodcock, +woodpecker, and other wild birds are caught, lest I pursue unseasonably +and too minutely single instances. Lastly, with his fish-hook and net +does not the fisherman catch the fish in the sea, in the lakes, in +fish-ponds, or in rivers? But the hook is of iron, and sometimes we see +lead or iron weights attached to the net. And most fish that are caught +are afterward cut up and disembowelled with knives and axes. But, more +than enough has been said on the matter of food. + +Now I will speak of clothing, which is made out of wool, flax, feathers, +hair, fur, or leather. First the sheep are sheared, then the wool is +combed. Next the threads are drawn out, while later the warp is +suspended in the shuttle under which passes the wool. This being struck +by the comb, at length cloth is formed either from threads alone or from +threads and hair. Flax, when gathered, is first pulled by hooks. Then it +is dipped in water and afterward dried, beaten into tow with a heavy +mallet, and carded, then drawn out into threads, and finally woven into +cloth. But has the artisan or weaver of the cloth any instrument not +made of iron? Can one be made of wood without the aid of iron? The +cloth or web must be cut into lengths for the tailor. Can this be done +without knife or scissors? Can the tailor sew together any garments +without a needle? Even peoples dwelling beyond the seas cannot make a +covering for their bodies, fashioned of feathers, without these same +implements. Neither can the furriers do without them in sewing together +the pelts of any kind of animals. The shoemaker needs a knife to cut the +leather, another to scrape it, and an awl to perforate it before he can +make shoes. These coverings for the body are either woven or stitched. +Buildings too, which protect the same body from rain, wind, cold, and +heat, are not constructed without axes, saws, and augers. + +But what need of more words? If we remove metals from the service of +man, all methods of protecting and sustaining health and more carefully +preserving the course of life are done away with. If there were no +metals, men would pass a horrible and wretched existence in the midst of +wild beasts; they would return to the acorns and fruits and berries of +the forest. They would feed upon the herbs and roots which they plucked +up with their nails. They would dig out caves in which to lie down at +night, and by day they would rove in the woods and plains at random like +beasts, and inasmuch as this condition is utterly unworthy of humanity, +with its splendid and glorious natural endowment, will anyone be so +foolish or obstinate as not to allow that metals are necessary for food +and clothing and that they tend to preserve life? + +Moreover, as the miners dig almost exclusively in mountains otherwise +unproductive, and in valleys invested in gloom, they do either slight +damage to the fields or none at all. Lastly, where woods and glades are +cut down, they may be sown with grain after they have been cleared from +the roots of shrubs and trees. These new fields soon produce rich crops, +so that they repair the losses which the inhabitants suffer from +increased cost of timber. Moreover, with the metals which are melted +from the ore, birds without number, edible beasts and fish can be +purchased elsewhere and brought to these mountainous regions. + +I will pass to the illustrations I have mentioned. Bias of Priene, when +his country was taken, carried away out of the city none of his +valuables. So strong a man with such a reputation for wisdom had no need +to fear personal danger from the enemy, but this in truth cannot be said +of him because he hastily took to flight; the throwing away of his goods +does not seem to me so great a matter, for he had lost his house, his +estates, and even his country, than which nothing is more precious. Nay, +I should be convinced of Bias's contempt and scorn for possessions of +this kind, if before his country was captured he had bestowed them +freely on relations and friends, or had distributed them to the very +poor, for this he could have done freely and without question. Whereas +his conduct, which the Greeks admire so greatly, was due, it would seem, +to his being driven out by the enemy and stricken with fear. Socrates in +truth did not despise gold, but would not accept money for his teaching. +As for Aristippus of Cyrene, if he had gathered and saved the gold which +he ordered his slaves to throw away, he might have bought the things +which he needed for the necessaries of life, and he would not, by reason +of his poverty, have then been obliged to flatter the tyrant Dionysius, +nor would he ever have been called by him a King's dog. For this reason +Horace, speaking of Damasippus when reviling Staberus for valuing riches +very highly, says: + + "What resemblance has the Grecian Aristippus to this fellow? He + who commanded his slaves to throw away the gold in the midst of + Libya because they went too slowly, impeded by the weight of + their burden--which of these two men is the more insane?"[21] + +Insane indeed is he who makes more of riches than of virtue. Insane also +is he who rejects them and considers them as worth nothing, instead of +using them with reason. Yet as to the gold which Aristippus on another +occasion flung into the sea from a boat, this he did with a wise and +prudent mind. For learning that it was a pirate boat in which he was +sailing, and fearing for his life, he counted his gold and then throwing +it of his own will into the sea, he groaned as if he had done it +unwillingly. But afterward, when he escaped the peril, he said: "It is +better that this gold itself should be lost than that I should have +perished because of it." Let it be granted that some philosophers, as +well as Anacreon of Teos, despised gold and silver. Anaxagoras of +Clazomenae also gave up his sheep-farms and became a shepherd. Crates +the Theban too, being annoyed that his estate and other kinds of wealth +caused him worry, and that in his contemplations his mind was thereby +distracted, resigned a property valued at ten talents, and taking a +cloak and wallet, in poverty devoted all his thought and efforts to +philosophy. Is it true that because these philosophers despised money, +all others declined wealth in cattle? Did they refuse to cultivate lands +or to dwell in houses? There were certainly many, on the other hand, +who, though affluent, became famous in the pursuit of learning and in +the knowledge of divine and human laws, such as Aristotle, Cicero, and +Seneca. As for Phocion, he did not deem it honest to accept the gold +sent to him by Alexander. For if he had consented to use it, the king as +much as himself would have incurred the hatred and aversion of the +Athenians, and these very people were afterward so ungrateful toward +this excellent man that they compelled him to drink hemlock. For what +would have been less becoming to Marcus Curius and Fabricius Luscinus +than to accept gold from their enemies, who hoped that by these means +those leaders could be corrupted or would become odious to their fellow +citizens, their purpose being to cause dissentions among the Romans and +destroy the Republic utterly. Lycurgus, however, ought to have given +instructions to the Spartans as to the use of gold and silver, instead +of abolishing things good in themselves. As to the Babytacenses, who +does not see that they were senseless and envious? For with their gold +they might have bought things of which they were in need, or even given +it to neighbouring peoples to bind them more closely to themselves with +gifts and favours. Finally, the Scythians, by condemning the use of gold +and silver alone, did not free themselves utterly from avarice, because +although he is not enjoying them, one who can possess other forms of +property may also become avaricious. + +Now let us reply to the attacks hurled against the products of mines. In +the first place, they call gold and silver the scourge of mankind +because they are the cause of destruction and ruin to their possessors. +But in this manner, might not anything that we possess be called a +scourge to human kind,--whether it be a horse, or a garment, or anything +else? For, whether one rides a splendid horse, or journeys well clad, he +would give occasion to a robber to kill him. Are we then not to ride on +horses, but to journey on foot, because a robber has once committed a +murder in order that he may steal a horse? Or are we not to possess +clothing, because a vagabond with a sword has taken a traveller's life +that he may rob him of his garment? The possession of gold and silver is +similar. Seeing then that men cannot conveniently do all these things, +we should be on our guard against robbers, and because we cannot always +protect ourselves from their hands, it is the special duty of the +magistrate to seize wicked and villainous men for torture, and, if need +be, for execution. + +Again, the products of the mines are not themselves the cause of war. +Thus, for example, when a tyrant, inflamed with passion for a woman of +great beauty, makes war on the inhabitants of her city, the fault lies +in the unbridled lust of the tyrant and not in the beauty of the woman. +Likewise, when another man, blinded by a passion for gold and silver, +makes war upon a wealthy people, we ought not to blame the metals but +transfer all blame to avarice. For frenzied deeds and disgraceful +actions, which are wont to weaken and dishonour natural and civil laws, +originate from our own vices. Wherefore Tibullus is wrong in laying the +blame for war on gold, when he says: "This is the fault of a rich man's +gold; there were no wars when beech goblets were used at banquets." But +Virgil, speaking of Polymnestor, says that the crime of the murderer +rests on avarice: + + "He breaks all law; he murders Polydorus, and obtains gold by + violence. To what wilt thou not drive mortal hearts, thou + accursed hunger for gold?" + +And again, justly, he says, speaking of Pygmalion, who killed Sichaeus: + + "And blinded with the love of gold, he slew him unawares with + stealthy sword."[22] + +For lust and eagerness after gold and other things make men blind, and +this wicked greed for money, all men in all times and places have +considered dishonourable and criminal. Moreover, those who have been so +addicted to avarice as to be its slaves have always been regarded as +mean and sordid. Similarly, too, if by means of gold and silver and gems +men can overcome the chastity of women, corrupt the honour of many +people, bribe the course of justice and commit innumerable wickednesses, +it is not the metals which are to be blamed, but the evil passions of +men which become inflamed and ignited; or it is due to the blind and +impious desires of their minds. But although these attacks against gold +and silver may be directed especially against money, yet inasmuch as the +Poets one after another condemn it, their criticism must be met, and +this can be done by one argument alone. Money is good for those who use +it well; it brings loss and evil to those who use it ill. Hence, very +rightly, Horace says: + + "Dost thou not know the value of money; and what uses it + serves? It buys bread, vegetables, and a pint of wine." + +And again in another place: + + "Wealth hoarded up is the master or slave of each possessor; it + should follow rather than lead, the 'twisted rope.'"[23] + +When ingenious and clever men considered carefully the system of barter, +which ignorant men of old employed and which even to-day is used by +certain uncivilised and barbarous races, it appeared to them so +troublesome and laborious that they invented money. Indeed, nothing more +useful could have been devised, because a small amount of gold and +silver is of as great value as things cumbrous and heavy; and so peoples +far distant from one another can, by the use of money, trade very easily +in those things which civilised life can scarcely do without. + +The curses which are uttered against iron, copper, and lead have no +weight with prudent and sensible men, because if these metals were done +away with, men, as their anger swelled and their fury became unbridled, +would assuredly fight like wild beasts with fists, heels, nails, and +teeth. They would strike each other with sticks, hit one another with +stones, or dash their foes to the ground. Moreover, a man does not kill +another with iron alone, but slays by means of poison, starvation, or +thirst. He may seize him by the throat and strangle him; he may bury him +alive in the ground; he may immerse him in water and suffocate him; he +may burn or hang him; so that he can make every element a participant in +the death of men. Or, finally, a man may be thrown to the wild beasts. +Another may be sewn up wholly except his head in a sack, and thus be +left to be devoured by worms; or he may be immersed in water until he is +torn to pieces by sea-serpents. A man may be boiled in oil; he may be +greased, tied with ropes, and left exposed to be stung by flies and +hornets; he may be put to death by scourging with rods or beating with +cudgels, or struck down by stoning, or flung from a high place. +Furthermore, a man may be tortured in more ways than one without the use +of metals; as when the executioner burns the groins and armpits of his +victim with hot wax; or places a cloth in his mouth gradually, so that +when in breathing he draws it slowly into his gullet, the executioner +draws it back suddenly and violently; or the victim's hands are fastened +behind his back, and he is drawn up little by little with a rope and +then let down suddenly. Or similarly, he may be tied to a beam and a +heavy stone fastened by a cord to his feet, or finally his limbs may be +torn asunder. From these examples we see that it is not metals that are +to be condemned, but our vices, such as anger, cruelty, discord, passion +for power, avarice, and lust. + +The question next arises, whether we ought to count metals amongst the +number of good things or class them amongst the bad. The Peripatetics +regarded all wealth as a good thing, and merely spoke of externals as +having to do with neither the mind nor the body. Well, let riches be an +external thing. And, as they said, many other things may be classed as +good if it is in one's power to use them either well or ill. For good +men employ them for good, and to them they are useful. The wicked use +them badly, and to them they are harmful. There is a saying of Socrates, +that just as wine is influenced by the cask, so the character of riches +is like their possessors. The Stoics, whose custom it is to argue subtly +and acutely, though they did not put wealth in the category of good +things, they did not count it amongst the evil ones, but placed it in +that class which they term neutral. For to them virtue alone is good, +and vice alone evil. The whole of what remains is indifferent. Thus, in +their conviction, it matters not whether one be in good health or +seriously ill; whether one be handsome or deformed. In short: + + "Whether, sprung from Inachus of old, and thus hast lived + beneath the sun in wealth, or hast been poor and despised among + men, it matters not." + +For my part, I see no reason why anything that is in itself of use +should not be placed in the class of good things. At all events, metals +are a creation of Nature, and they supply many varied and necessary +needs of the human race, to say nothing about their uses in adornment, +which are so wonderfully blended with utility. Therefore, it is not +right to degrade them from the place they hold among the good things. In +truth, if there is a bad use made of them, should they on that account +be rightly called evils? For of what good things can we not make an +equally bad or good use? Let me give examples from both classes of what +we term good. Wine, by far the best drink, if drunk in moderation, aids +the digestion of food, helps to produce blood, and promotes the juices +in all parts of the body. It is of use in nourishing not only the body +but the mind as well, for it disperses our dark and gloomy thoughts, +frees us from cares and anxiety, and restores our confidence. If drunk +in excess, however, it injures and prostrates the body with serious +disease. An intoxicated man keeps nothing to himself; he raves and +rants, and commits many wicked and infamous acts. On this subject +Theognis wrote some very clever lines, which we may render thus: + + "Wine is harmful if taken with greedy lips, but if drunk in + moderation it is wholesome."[25] + +But I linger too long over extraneous matters. I must pass on to the +gifts of body and mind, amongst which strength, beauty, and genius occur +to me. If then a man, relying on his strength, toils hard to maintain +himself and his family in an honest and respectable manner, he uses the +gift aright, but if he makes a living out of murder and robbery, he uses +it wrongly. Likewise, too, if a lovely woman is anxious to please her +husband alone she uses her beauty aright, but if she lives wantonly and +is a victim of passion, she misuses her beauty. In like manner, a youth +who devotes himself to learning and cultivates the liberal arts, uses +his genius rightly. But he who dissembles, lies, cheats, and deceives by +fraud and dishonesty, misuses his abilities. Now, the man who, because +they are abused, denies that wine, strength, beauty, or genius are good +things, is unjust and blasphemous towards the Most High God, Creator of +the World; so he who would remove metals from the class of blessings +also acts unjustly and blasphemously against Him. Very true, therefore, +are the words which certain Greek poets have written, as Pindar: + + "Money glistens, adorned with virtue; it supplies the means by + which thou mayest act well in whatever circumstances fate may + have in store for thee."[26] + +And Sappho: + + "Without the love of virtue gold is a dangerous and harmful + guest, but when it is associated with virtue, it becomes the + source and height of good." + +And Callimachus: + + "Riches do not make men great without virtue; neither do + virtues themselves make men great without some wealth." + +And Antiphanes: + + "Now, by the gods, why is it necessary for a man to grow rich? + Why does he desire to possess much money unless that he may, as + much as possible, help his friends, and sow the seeds of a + harvest of gratitude, sweetest of the goddesses."[27] + +Having thus refuted the arguments and contentions of adversaries, let us +sum up the advantages of the metals. In the first place, they are useful +to the physician, for they furnish liberally the ingredients for +medicines, by which wounds and ulcers are cured, and even plagues; so +that certainly if there were no other reasons why we should explore the +depths of the earth, we should for the sake of medicine alone dig in the +mines. Again, the metals are of use to painters, because they yield +certain pigments which, when united with the painter's slip, are injured +less than others by the moisture from without. Further, mining is useful +to the architects, for thus is found marble, which is suitable not only +for strengthening large buildings, but also for decoration. It is, +moreover, helpful to those whose ambition urges them toward immortal +glory, because it yields metals from which are made coins, statues, and +other monuments, which, next to literary records, give men in a sense +immortality. The metals are useful to merchants with very great cause, +for, as I have stated elsewhere, the use of money which is made from +metals is much more convenient to mankind than the old system of +exchange of commodities. In short, to whom are the metals not of use? In +very truth, even the works of art, elegant, embellished, elaborate, +useful, are fashioned in various shapes by the artist from the metals +gold, silver, brass, lead, and iron. How few artists could make +anything that is beautiful and perfect without using metals? Even if +tools of iron or brass were not used, we could not make tools of wood +and stone without the help of metal. From all these examples are evident +the benefits and advantages derived from metals. We should not have had +these at all unless the science of mining and metallurgy had been +discovered and handed down to us. Who then does not understand how +highly useful they are, nay rather, how necessary to the human race? In +a word, man could not do without the mining industry, nor did Divine +Providence will that he should. + +Further, it has been asked whether to work in metals is honourable +employment for respectable people or whether it is not degrading and +dishonourable. We ourselves count it amongst the honourable arts. For +that art, the pursuit of which is unquestionably not impious, nor +offensive, nor mean, we may esteem honourable. That this is the nature +of the mining profession, inasmuch as it promotes wealth by good and +honest methods, we shall show presently. With justice, therefore, we may +class it amongst honourable employments. In the first place, the +occupation of the miner, which I must be allowed to compare with other +methods of acquiring great wealth, is just as noble as that of +agriculture; for, as the farmer, sowing his seed in his fields injures +no one, however profitable they may prove to him, so the miner digging +for his metals, albeit he draws forth great heaps of gold or silver, +hurts thereby no mortal man. Certainly these two modes of increasing +wealth are in the highest degree both noble and honourable. The booty of +the soldier, however, is frequently impious, because in the fury of the +fighting he seizes all goods, sacred as well as profane. The most just +king may have to declare war on cruel tyrants, but in the course of it +wicked men cannot lose their wealth and possessions without dragging +into the same calamity innocent and poor people, old men, matrons, +maidens, and orphans. But the miner is able to accumulate great riches +in a short time, without using any violence, fraud, or malice. That old +saying is, therefore, not always true that "Every rich man is either +wicked himself, or is the heir to wickedness." + +Some, however, who contend against us, censure and attack miners by +saying that they and their children must needs fall into penury after a +short time, because they have heaped up riches by improper means. +According to them nothing is truer than the saying of the poet Naevius: + + "Ill gotten gains in ill fashion slip away." + +The following are some of the wicked and sinful methods by which they +say men obtain riches from mining. When a prospect of obtaining metals +shows itself in a mine, either the ruler or magistrate drives out the +rightful owners of the mines from possession, or a shrewd and cunning +neighbour perhaps brings a law-suit against the old possessors in order +to rob them of some part of their property. Or the mine superintendent +imposes on the owners such a heavy contribution on shares, that if they +cannot pay, or will not, they lose their rights of possession; while the +superintendent, contrary to all that is right, seizes upon all that they +have lost. Or, finally, the mine foreman may conceal the vein by +plastering over with clay that part where the metal abounds, or by +covering it with earth, stones, stakes, or poles, in the hope that after +several years the proprietors, thinking the mine exhausted, will abandon +it, and the foreman can then excavate that remainder of the ore and keep +it for himself. They even state that the scum of the miners exist wholly +by fraud, deceit, and lying. For to speak of nothing else, but only of +those deceits which are practised in buying and selling, it is said they +either advertise the veins with false and imaginary praises, so that +they can sell the shares in the mines at one-half more than they are +worth, or on the contrary, they sometimes detract from the estimate of +them so that they can buy shares for a small price. By exposing such +frauds our critics suppose all good opinion of miners is lost. Now, all +wealth, whether it has been gained by good or evil means, is liable by +some adverse chance to vanish away. It decays and is dissipated by the +fault and carelessness of the owner, since he loses it through laziness +and neglect, or wastes and squanders it in luxuries, or he consumes and +exhausts it in gifts, or he dissipates and throws it away in gambling: + +"Just as though money sprouted up again, renewed from an exhausted +coffer, and was always to be obtained from a full heap." + +It is therefore not to be wondered at if miners do not keep in mind the +counsel given by King Agathocles: "Unexpected fortune should be held in +reverence," for by not doing so they fall into penury; and particularly +when the miners are not content with moderate riches, they not rarely +spend on new mines what they have accumulated from others. But no just +ruler or magistrate deprives owners of their possessions; that, however, +may be done by a tyrant, who may cruelly rob his subjects not only of +their goods honestly obtained, but even of life itself. And yet whenever +I have inquired into the complaints which are in common vogue, I always +find that the owners who are abused have the best of reasons for driving +the men from the mines; while those who abuse the owners have no reason +to complain about them. Take the case of those who, not having paid +their contributions, have lost the right of possession, or those who +have been expelled by the magistrate out of another man's mine: for some +wicked men, mining the small veins branching from the veins rich in +metal, are wont to invade the property of another person. So the +magistrate expels these men accused of wrong, and drives them from the +mine. They then very frequently spread unpleasant rumours concerning +this amongst the populace. Or, to take another case: when, as often +happens, a dispute arises between neighbours, arbitrators appointed by +the magistrate settle it, or the regular judges investigate and give +judgment. Consequently, when the judgment is given, inasmuch as each +party has consented to submit to it, neither side should complain of +injustice; and when the controversy is adjudged, inasmuch as the +decision is in accordance with the laws concerning mining, one of the +parties cannot be injured by the law. I do not vigorously contest the +point, that at times a mine superintendent may exact a larger +contribution from the owners than necessity demands. Nay, I will admit +that a foreman may plaster over, or hide with a structure, a vein where +it is rich in metals. Is the wickedness of one or two to brand the many +honest with fraud and trickery? What body is supposed to be more pious +and virtuous in the Republic than the Senate? Yet some Senators have +been detected in peculations, and have been punished. Is this any reason +that so honourable a house should lose its good name and fame? The +superintendent cannot exact contributions from the owners without the +knowledge and permission of the Bergmeister or the deputies; for this +reason deception of this kind is impossible. Should the foremen be +convicted of fraud, they are beaten with rods; or of theft, they are +hanged. It is complained that some sellers and buyers of the shares in +mines are fraudulent. I concede it. But can they deceive anyone except a +stupid, careless man, unskilled in mining matters? Indeed, a wise and +prudent man, skilled in this art, if he doubts the trustworthiness of a +seller or buyer, goes at once to the mine that he may for himself +examine the vein which has been so greatly praised or disparaged, and +may consider whether he will buy or sell the shares or not. But people +say, though such an one can be on his guard against fraud, yet a simple +man and one who is easily credulous, is deceived. But we frequently see +a man who is trying to mislead another in this way deceive himself, and +deservedly become a laughing-stock for everyone; or very often the +defrauder as well as the dupe is entirely ignorant of mining. If, for +instance, a vein has been found to be abundant in ore, contrary to the +idea of the would-be deceiver, then he who was to have been cheated gets +a profit, and he who has been the deceiver loses. Nevertheless, the +miners themselves rarely buy or sell shares, but generally they have +_jurati venditores_[28] who buy and sell at such prices as they have +been instructed to give or accept. Seeing therefore, that magistrates +decide disputes on fair and just principles, that honest men deceive +nobody, while a dishonest one cannot deceive easily, or if he does he +cannot do so with impunity, the criticism of those who wish to disparage +the honesty of miners has therefore no force or weight. + +In the next place, the occupation of the miner is objectionable to +nobody. For who, unless he be naturally malevolent and envious, will +hate the man who gains wealth as it were from heaven? Or who will hate a +man who to amplify his fortune, adopts a method which is free from +reproach? A moneylender, if he demands an excessive interest, incurs the +hatred of men. If he demands a moderate and lawful rate, so that he is +not injurious to the public generally and does not impoverish them, he +fails to become very rich from his business. Further, the gain derived +from mining is not sordid, for how can it be such, seeing that it is so +great, so plentiful, and of so innocent a nature. A merchant's profits +are mean and base when he sells counterfeit and spurious merchandise, or +puts far too high a price on goods that he has purchased for little; for +this reason the merchant would be held in no less odium amongst good +men than is the usurer, did they not take account of the risk he runs to +secure his merchandise. In truth, those who on this point speak +abusively of mining for the sake of detracting from its merits, say that +in former days men convicted of crimes and misdeeds were sentenced to +the mines and were worked as slaves. But to-day the miners receive pay, +and are engaged like other workmen in the common trades. + +Certainly, if mining is a shameful and discreditable employment for a +gentleman because slaves once worked mines, then agriculture also will +not be a very creditable employment, because slaves once cultivated the +fields, and even to-day do so among the Turks; nor will architecture be +considered honest, because some slaves have been found skilful in that +profession; nor medicine, because not a few doctors have been slaves; +nor will any other worthy craft, because men captured by force of arms +have practised it. Yet agriculture, architecture, and medicine are none +the less counted amongst the number of honourable professions; +therefore, mining ought not for this reason to be excluded from them. +But suppose we grant that the hired miners have a sordid employment. We +do not mean by miners only the diggers and other workmen, but also those +skilled in the mining arts, and those who invest money in mines. Amongst +them can be counted kings, princes, republics, and from these last the +most esteemed citizens. And finally, we include amongst the overseers of +mines the noble Thucydides, the historian, whom the Athenians placed in +charge of the mines of Thasos.[29] And it would not be unseemly for the +owners themselves to work with their own hands on the works or ore, +especially if they themselves have contributed to the cost of the mines. +Just as it is not undignified for great men to cultivate their own land. +Otherwise the Roman Senate would not have created Dictator L. Quintius +Cincinnatus, as he was at work in the fields, nor would it have summoned +to the Senate House the chief men of the State from their country +villas. Similarly, in our day, Maximilian Cæsar would not have enrolled +Conrad in the ranks of the nobles known as Counts; Conrad was really +very poor when he served in the mines of Schneeberg, and for that reason +he was nicknamed the "poor man"; but not many years after, he attained +wealth from the mines of Fürst, which is a city in Lorraine, and took +his name from "Luck."[30] Nor would King Vladislaus have restored to the +Assembly of Barons, Tursius, a citizen of Cracow, who became rich +through the mines in that part of the kingdom of Hungary which was +formerly called Dacia.[31] Nay, not even the common worker in the mines +is vile and abject. For, trained to vigilance and work by night and day, +he has great powers of endurance when occasion demands, and easily +sustains the fatigues and duties of a soldier, for he is accustomed to +keep long vigils at night, to wield iron tools, to dig trenches, to +drive tunnels, to make machines, and to carry burdens. Therefore, +experts in military affairs prefer the miner, not only to a commoner +from the town, but even to the rustic. + +But to bring this discussion to an end, inasmuch as the chief callings +are those of the moneylender, the soldier, the merchant, the farmer, and +the miner, I say, inasmuch as usury is odious, while the spoil cruelly +captured from the possessions of the people innocent of wrong is wicked +in the sight of God and man, and inasmuch as the calling of the miner +excels in honour and dignity that of the merchant trading for lucre, +while it is not less noble though far more profitable than agriculture, +who can fail to realize that mining is a calling of peculiar dignity? +Certainly, though it is but one of ten important and excellent methods +of acquiring wealth in an honourable way, a careful and diligent man can +attain this result in no easier way than by mining. + + END OF BOOK I. + + +FOOTNOTES: + +[1] _Fibrae_--"fibres." See Note 6, p. 70. + +[2] _Commissurae saxorum_--"rock joints," "seams," or "cracks." Agricola +and all of the old authors laid a wholly unwarranted geologic value on +these phenomena. See description and footnotes, Book III., pages 43 and +72. + +[3] _Succi_--"juice," or _succi concreti_--"solidified juice." Ger. +Trans., _saffte_. The old English translators and mineralogists often +use the word juices in the same sense, and we have adopted it. The words +"solutions" and "salts" convey a chemical significance not warranted by +the state of knowledge in Agricola's time. Instances of the former use +of this word may be seen in Barba's "First Book of the Art of Metals," +(Trans. Earl Sandwich, London, 1674, p. 2, etc.,) and in Pryce's +_Mineralogia Cornubiensis_ (London, 1778, p. 25, 32). + +[4] In order that the reader should be able to grasp the author's point +of view as to his divisions of the Mineral Kingdom, we introduce here +his own statement from _De Natura Fossilium_, (p. 180). It is also +desirable to read the footnote on his theory of ore-deposits on pages 43 +to 53, and the review of _De Natura Fossilium_ given in the Appendix. + +"The subterranean inanimate bodies are divided into two classes, one of +which, because it is a fluid or an exhalation, is called by those names, +and the other class is called the minerals. Mineral bodies are +solidified from particles of the same substance, such as pure gold, each +particle of which is gold, or they are of different substances such as +lumps which consist of earth, stone, and metal; these latter may be +separated into earth, stone and metal, and therefore the first is not a +mixture while the last is called a mixture. The first are again divided +into simple and compound minerals. The simple minerals are of four +classes, namely earths, solidified juices, stones and metals, while the +mineral compounds are of many sorts, as I shall explain later. + +"Earth is a simple mineral body which may be kneaded in the hands when +moistened, or from which lute is made when it has been wetted. Earth, +properly so called, is found enclosed in veins or veinlets, or +frequently on the surface in fields and meadows. This definition is a +general one. The harder earth, although moistened by water, does not at +once become lute, but does turn into lute if it remains in water for +some time. There are many species of earths, some of which have names +but others are unnamed. + +"Solidified juices are dry and somewhat hard (_subdurus_) mineral bodies +which when moistened with water do not soften but liquefy instead; or if +they do soften, they differ greatly from the earths by their +unctuousness (_pingue_) or by the material of which they consist. +Although occasionally they have the hardness of stone, yet because they +preserve the form and nature which they had when less hard, they can +easily be distinguished from the stones. The juices are divided into +'meagre' and unctuous (_macer et pinguis_). The 'meagre' juices, since +they originate from three different substances, are of three species. +They are formed from a liquid mixed with earth, or with metal, or with a +mineral compound. To the first species belong salt and _Nitrum_ (soda); +to the second, chrysocolla, verdigris, iron-rust, and azure; to the +third, vitriol, alum, and an acrid juice which is unnamed. The first two +of these latter are obtained from pyrites, which is numbered amongst the +compound minerals. The third of these comes from _Cadmia_ (in this case +the cobalt-zinc-arsenic minerals; the acrid juice is probably zinc +sulphate). To the unctuous juices belong these species: sulphur, +bitumen, realgar and orpiment. Vitriol and alum, although they are +somewhat unctuous yet do not burn, and they differ in their origin from +the unctuous juices, for the latter are forced out from the earth by +heat, whereas the former are produced when pyrites is softened by +moisture. + +"Stone is a dry and hard mineral body which may either be softened by +remaining for a long time in water and be reduced to powder by a fierce +fire; or else it does not soften with water but the heat of a great fire +liquefies it. To the first species belong those stones which have been +solidified by heat, to the second those solidified (literally +'congealed') by cold. These two species of stones are constituted from +their own material. However, writers on natural subjects who take into +consideration the quantity and quality of stones and their value, divide +them into four classes. The first of these has no name of its own but is +called in common parlance 'stone': to this class belong loadstone, +jasper (or bloodstone) and _Aetites_ (geodes?). The second class +comprises hard stones, either pellucid or ornamental, with very +beautiful and varied colours which sparkle marvellously; they are called +gems. The third comprises stones which are only brilliant after they +have been polished, and are usually called marble. The fourth are called +rocks; they are found in quarries, from which they are hewn out for use +in building, and they are cut into various shapes. None of the rocks +show colour or take a polish. Few of the stones sparkle; fewer still are +transparent. Marble is sometimes only distinguishable from opaque gems +by its volume; rock is always distinguishable from stones properly +so-called by its volume. Both the stones and the gems are usually to be +found in veins and veinlets which traverse the rocks and marble. These +four classes, as I have already stated, are divided into many species, +which I will explain in their proper place. + +"Metal is a mineral body, by nature either liquid or somewhat hard. The +latter may be melted by the heat of the fire, but when it has cooled +down again and lost all heat, it becomes hard again and resumes its +proper form. In this respect it differs from the stone which melts in +the fire, for although the latter regain its hardness, yet it loses its +pristine form and properties. Traditionally there are six different +kinds of metals, namely gold, silver, copper, iron, tin and lead. There +are really others, for quicksilver is a metal, although the Alchemists +disagree with us on this subject, and bismuth is also. The ancient Greek +writers seem to have been ignorant of bismuth, wherefore Ammonius +rightly states that there are many species of metals, animals, and +plants which are unknown to us. _Stibium_ when smelted in the crucible +and refined has as much right to be regarded as a proper metal as is +accorded to lead by writers. If when smelted, a certain portion be added +to tin, a bookseller's alloy is produced from which the type is made +that is used by those who print books on paper. Each metal has its own +form which it preserves when separated from those metals which were +mixed with it. Therefore neither electrum nor _Stannum_ is of itself a +real metal, but rather an alloy of two metals. Electrum is an alloy of +gold and silver, _Stannum_ of lead and silver (see note 33, p. 473). And +yet if silver be parted from the electrum, then gold remains and not +electrum; if silver be taken away from _Stannum_, then lead remains and +not _Stannum_. Whether brass, however, is found as a native metal or +not, cannot be ascertained with any surety. We only know of the +artificial brass, which consists of copper tinted with the colour of the +mineral calamine. And yet if any should be dug up, it would be a proper +metal. Black and white copper seem to be different from the red kind. +Metal, therefore, is by nature either solid, as I have stated, or fluid, +as in the unique case of quicksilver. But enough now concerning the +simple kinds. + +"I will now speak of the compounds which are composed of the simple +minerals cemented together by nature, and under the word 'compound' I +now discuss those mineral bodies which consist of two or three simple +minerals. They are likewise mineral substances, but so thoroughly mixed +and alloyed that even in the smallest part there is not wanting any +substance that is contained in the whole. Only by the force of the fire +is it possible to separate one of the simple mineral substances from +another; either the third from the other two, or two from the third, if +there were three in the same compound. These two, three or more bodies +are so completely mixed into one new species that the pristine form of +none of these is recognisable. + +"The 'mixed' minerals, which are composed of those same simple minerals, +differ from the 'compounds,' in that the simple minerals each preserves +its own form so that they can be separated one from the other not only +by fire but sometimes by water and sometimes by hand. As these two +classes differ so greatly from one another I usually use two different +words in order to distinguish one from the other. I am well aware that +Galen calls the metallic earth a compound which is really a mixture, but +he who wishes to instruct others should bestow upon each separate thing +a definite name." + +For convenience of reference we may reduce the above to a diagram as +follows: + + 1. Fluids and gases. + + { { Earths + { (a) Simple { Solidified juices + { minerals { Stones + { { Metals + { A. Homogenous { + { bodies { + { { (b) Compound { Being heterogeneous mixtures + { { minerals { of (a) + { + 2. Mineral { + bodies { + { + { B. Mixtures. Being homogenous mixtures of (a) + +[5] _Experiendae_--"a trial." That actual assaying in its technical +sense is meant, is sufficiently evident from Book VII. + +[6] _... plumbum ... candidum ac cinereum vel nigrum_. "Lead ... white, +or ash-coloured, or black." Agricola himself coined the term _plumbum +cinereum_ for bismuth, no doubt following the Roman term for +tin--_plumbum candidum_. The following passage from _Bermannus_ (p. 439) +is of interest, for it appears to be the first description of bismuth, +although mention of it occurs in the _Nützlich Bergbüchlin_ (see +Appendix B). "_Bermannus_: I will show you another kind of mineral which +is numbered amongst metals, but appears to me to have been unknown to +the Ancients; we call it _bisemutum_. _Naevius_: Then in your opinion +there are more kinds of metals than the seven commonly believed? +_Bermannus_: More, I consider; for this which just now I said we called +_bisemutum_, cannot correctly be called _plumbum candidum_ (tin), nor +_nigrum_ (lead), but is different from both and is a third one. _Plumbum +candidum_ is whiter and _plumbum nigrum_ is darker, as you see. +_Naevius_: We see that this is of the colour of _galena_. _Ancon_: How +then can _bisemutum_, as you call it, be distinguished from _galena_? +_Bermannus_: Easily; when you take it in your hands it stains them with +black, unless it is quite hard. The hard kind is not friable like +_galena_, but can be cut. It is blacker than the kind of _rudis_ silver +which we say is almost the colour of lead, and thus is different from +both. Indeed, it not rarely contains some silver. It generally indicates +that there is silver beneath the place where it is found, and because of +this our miners are accustomed to call it the 'roof of silver.' They are +wont to roast this mineral, and from the better part they make metal; +from the poorer part they make a pigment of a kind not to be despised." + +[7] _Nitrum._ The Ancients comprised many salts under this head, but +Agricola in the main uses it for soda, although sometimes he includes +potash. He usually, however, refers to potash as _lixivium_ or salt +therefrom, and by other distinctive terms. For description of method of +manufacture and discussion, see Book XII., p. 558. + +[8] _Atramentum sutorium_--"Shoemaker's blacking." See p. 572 for +description of method of manufacture and historical footnote. In the +main Agricola means green vitriol, but he does describe three main +varieties, green, blue, and white (_De Natura Fossilium_, p. 219). The +blue was of course copper sulphate, and it is fairly certain that the +white was zinc vitriol. + +[9] _Lavandi_--"Washing." By this term the author includes all the +operations of sluicing, buddling, and wet concentration generally. There +is no English equivalent of such wide application, and there is some +difficulty in interpretation without going further than the author +intends. Book VIII. is devoted to the subject. + +[10] _Operam et oleum perdit_--"loss of labour and oil." + +[11] In _Veteribus et Novis Metallis_, and _Bermannus_, Agricola states +that the mines of Schemnitz were worked 800 years before that time +(1530), or about 750 A.D., and, further, that the lead mines of Goslar +in the Hartz were worked by Otho the Great (936-973), and that the +silver mines at Freiberg were discovered during the rule of Prince Otho +(about 1170). To continue the argument to-day we could add about 360 +years more of life to the mines of Goslar and Freiberg. See also Note +16, p. 36, and note 19, p. 37. + +[12] Xenophon. Essay on the Revenues of Athens, I., 5. + +[13] Ovid, _Metamorphoses_, I., 137 to 143. + +[14] Diogenes Laertius, II., 5. The lines are assigned, however, to +Philemon, not Euripides. (Kock, _Comicorum Atticorum Fragmenta_ II., +512). + +[15] We have not considered it of sufficient interest to cite the +references to all of the minor poets and those whose preserved works are +but fragmentary. The translations from the Greek into Latin are not +literal and suffer again by rendering into English; we have however +considered it our duty to translate Agricola's view of the meaning. + +[16] Diogenes Laertius, II. + +[17] An inspection of the historical incidents mentioned here and +further on, indicates that Agricola relied for such information on +Diogenes Laertius, Plutarch, Livy, Valerius Maximus, Pliny, and often +enough on Homer, Horace, and Virgil. + +[18] Juvenal. _Satires_ I., l. 112, and VI., l. 298. + +[19] Pliny, XXXIV., 39. + +[20] Horace. _Odes_, I., 35, ll. 17-20. + +[21] Horace. _Satires_, II., 3, ll. 99-102. + +[22] Virgil. _Æneid_, III., l. 55, and I., l. 349. + +[23] Horace. _Satires_, I., l. 73; and Epistle, I., 10, l. 47. + +[25] Theognis. Maxims, II., l. 210. + +[26] Pindar. _Olymp._ II., 58-60. + +[27] Antiphanes, 4. + +[28] _Jurati Venditores_--"Sworn brokers." (?) + +[29] There is no doubt that Thucydides had some connection with gold +mines; he himself is the authority for the statement that he worked +mines in Thrace. Agricola seems to have obtained his idea that +Thucydides held an appointment from the Athenians in charge of mines in +Thasos, from Marcellinus (_Vita_, Thucydides, 30), who also says that +Thucydides obtained possession of mines in Thrace through his marriage +with a Thracian woman, and that it was while residing on the mines at +Scapte-Hyle that he wrote his history. Later scholars, however, find +little warrant for these assertions. The gold mines of Thasos--an island +off the mainland of Thrace--are frequently mentioned by the ancient +authors. Herodotus, VI., 46-47, says:--"Their (the Thasians') revenue +was derived partly from their possessions upon the mainland, partly from +the mines which they owned. They were masters of the gold mines of +Scapte-Hyle, the yearly produce of which amounted to eighty talents. +Their mines in Thasos yielded less, but still were so prolific that +besides being entirely free from land-tax they had a surplus of income +derived from the two sources of their territory on the mainland and +their mines, in common years two hundred and in best years three hundred +talents. I myself have seen the mines in question. By far the most +curious of them are those which the Phoenicians discovered at the time +when they went with Thasos and colonized the island, which took its name +from him. These Phoenician workings are in Thasos itself, between +Coenyra and a place called Aenyra over against Samothrace; a high +mountain has been turned upside down in the search for ores." +(Rawlinson's Trans.). The occasion of this statement of Herodotus was +the relations of the Thasians with Darius (521-486 B.C.). The date of +the Phoenician colonization of Thasos is highly nebular--anywhere from +1200 to 900 B.C. + +[30] Agricola, _De Veteribus et Novis Metallis_, Book I., p. 392, +says:--"Conrad, whose nickname in former years was 'pauper,' suddenly +became rich from the silver mines of Mount Jura, known as the +_Firstum_." He was ennobled with the title of Graf Cuntz von Glück by +the Emperor Maximilian (who was Emperor of the Holy Roman Empire, +1493-1519). Conrad was originally a working miner at Schneeberg where he +was known as Armer Cuntz (poor Cuntz or Conrad) and grew wealthy from +the mines of Fürst in Leberthal. This district is located in the Vosges +Mountains on the borders of Lorraine and Upper Alsace. The story of +Cuntz or Conrad von Glück is mentioned by Albinus (_Meissnische Land und +Berg Chronica_, Dresden, 1589, p. 116), Mathesius (_Sarepta_, Nuremberg, +1578, fol. XVI.), and by others. + +[31] Vladislaus III. was King of Poland, 1434-44, and also became King +of Hungary in 1440. Tursius seems to be a Latinized name and cannot be +identified. + + + + +BOOK II. + + +Qualities which the perfect miner should possess and the arguments which +are urged for and against the arts of mining and metallurgy, as well as +the people occupied in the industry, I have sufficiently discussed in +the first Book. Now I have determined to give more ample information +concerning the miners. + +In the first place, it is indispensable that they should worship God +with reverence, and that they understand the matters of which I am going +to speak, and that they take good care that each individual performs his +duties efficiently and diligently. It is decreed by Divine Providence +that those who know what they ought to do and then take care to do it +properly, for the most part meet with good fortune in all they +undertake; on the other hand, misfortune overtakes the indolent and +those who are careless in their work. No person indeed can, without +great and sustained effort and labour, store in his mind the knowledge +of every portion of the metallic arts which are involved in operating +mines. If a man has the means of paying the necessary expense, he hires +as many men as he needs, and sends them to the various works. Thus +formerly Sosias, the Thracian, sent into the silver mines a thousand +slaves whom he had hired from the Athenian Nicias, the son of +Niceratus[1]. But if a man cannot afford the expenditure he chooses of +the various kinds of mining that work which he himself can most easily +and efficiently do. Of these kinds, the two most important are the +making prospect trenches and the washing of the sands of rivers, for out +of these sands are often collected gold dust, or certain black stones +from which tin is smelted, or even gems are sometimes found in them; the +trenching occasionally lays bare at the grass-roots veins which are +found rich in metals. If therefore by skill or by luck, such sands or +veins shall fall into his hands, he will be able to establish his +fortune without expenditure, and from poverty rise to wealth. If on the +contrary, his hopes are not realized, then he can desist from washing or +digging. + +When anyone, in an endeavour to increase his fortune, meets the +expenditure of a mine alone, it is of great importance that he should +attend to his works and personally superintend everything that he has +ordered to be done. For this reason, he should either have his dwelling +at the mine, where he may always be in sight of the workmen and always +take care that none neglect their duties, or else he should live in the +neighbourhood, so that he may frequently inspect his mining works. Then +he may send word by a messenger to the workmen that he is coming more +frequently than he really intends to come, and so either by his arrival +or by the intimation of it, he so frightens the workmen that none of +them perform their duties otherwise than diligently. When he inspects +the mines he should praise the diligent workmen and occasionally give +them rewards, that they and the others may become more zealous in their +duties; on the other hand, he should rebuke the idle and discharge some +of them from the mines and substitute industrious men in their places. +Indeed, the owner should frequently remain for days and nights in the +mine, which, in truth, is no habitation for the idle and luxurious; it +is important that the owner who is diligent in increasing his wealth, +should frequently himself descend into the mine, and devote some time to +the study of the nature of the veins and stringers, and should observe +and consider all the methods of working, both inside and outside the +mine. Nor is this all he ought to do, for sometimes he should undertake +actual labour, not thereby demeaning himself, but in order to encourage +his workmen by his own diligence, and to teach them their art; for that +mine is well conducted in which not only the foreman, but also the owner +himself, gives instruction as to what ought to be done. A certain +barbarian, according to Xenophon, rightly remarked to the King of Persia +that "the eye of the master feeds the horse,"[2] for the master's +watchfulness in all things is of the utmost importance. + +When several share together the expenditure on a mine, it is convenient +and useful to elect from amongst their own number a mine captain, and +also a foreman. For, since men often look after their own interests but +neglect those of others, they cannot in this case take care of their own +without at the same time looking after the interests of the others, +neither can they neglect the interests of the others without neglecting +their own. But if no man amongst them be willing or able to undertake +and sustain the burdens of these offices, it will be to the common +interest to place them in the hands of most diligent men. Formerly +indeed, these things were looked after by the mining prefect[3], because +the owners were kings, as Priam, who owned the gold mines round Abydos, +or as Midas, who was the owner of those situated in Mount Bermius, or as +Gyges, or as Alyattes, or as Croesus, who was the owner of those mines +near a deserted town between Atarnea and Pergamum[4]; sometimes the +mines belonged to a Republic, as, for instance, the prosperous silver +mines in Spain which belonged to Carthage[5]; sometimes they were the +property of great and illustrious families, as were the Athenian mines +in Mount Laurion[6]. + +When a man owns mines but is ignorant of the art of mining, then it is +advisable that he should share in common with others the expenses, not +of one only, but of several mines. When one man alone meets the expense +for a long time of a whole mine, if good fortune bestows on him a vein +abundant in metals, or in other products, he becomes very wealthy; if, +on the contrary, the mine is poor and barren, in time he will lose +everything which he has expended on it. But the man who, in common with +others, has laid out his money on several mines in a region renowned for +its wealth of metals, rarely spends it in vain, for fortune usually +responds to his hopes in part. For when out of twelve veins in which he +has a joint interest one yields an abundance of metals, it not only +gives back to the owner the money he has spent, but also gives a profit +besides; certainly there will be for him rich and profitable mining, if +of the whole number, three, or four, or more veins should yield metal. +Very similar to this is the advice which Xenophon gave to the Athenians +when they wished to prospect for new veins of silver without suffering +loss. "There are," he said, "ten tribes of Athenians; if, therefore, the +State assigned an equal number of slaves to each tribe, and the tribes +participated equally in all the new veins, undoubtedly by this method, +if a rich vein of silver were found by one tribe, whatever profit were +made from it would assuredly be shared by the whole number. And if two, +three, or four tribes, or even half the whole number find veins, their +works would then become more profitable; and it is not probable that the +work of all the tribes will be disappointing."[7] Although this advice +of Xenophon is full of prudence, there is no opportunity for it except +in free and wealthy States; for those people who are under the authority +of kings and princes, or are kept in subjection by tyranny, do not dare, +without permission, to incur such expenditure; those who are endowed +with little wealth and resources cannot do so on account of insufficient +funds. Moreover, amongst our race it is not customary for Republics to +have slaves whom they can hire out for the benefit of the people[8]; +but, instead, nowadays those who are in authority administer the funds +for mining in the name of the State, not unlike private individuals. + +Some owners prefer to buy shares[9] in mines abounding in metals, +rather than to be troubled themselves to search for the veins; these men +employ an easier and less uncertain method of increasing their property. +Although their hopes in the shares of one or another mine may be +frustrated, the buyers of shares should not abandon the rest of the +mines, for all the money expended will be recovered with interest from +some other mine. They should not buy only high priced shares in those +mines producing metals, nor should they buy too many in neighbouring +mines where metal has not yet been found, lest, should fortune not +respond, they may be exhausted by their losses and have nothing with +which they may meet their expenses or buy other shares which may replace +their losses. This calamity overtakes those who wish to grow suddenly +rich from mines, and instead, they become very much poorer than before. +So then, in the buying of shares, as in other matters, there should be a +certain limit of expenditure which miners should set themselves, lest +blinded by the desire for excessive wealth, they throw all their money +away. Moreover, a prudent owner, before he buys shares, ought to go to +the mine and carefully examine the nature of the vein, for it is very +important that he should be on his guard lest fraudulent sellers of +shares should deceive him. Investors in shares may perhaps become less +wealthy, but they are more certain of some gain than those who mine for +metals at their own expense, as they are more cautious in trusting to +fortune. Neither ought miners to be altogether distrustful of fortune, +as we see some are, who as soon as the shares of any mine begin to go up +in value, sell them, on which account they seldom obtain even moderate +wealth. There are some people who wash over the dumps from exhausted and +abandoned mines, and those dumps which are derived from the drains of +tunnels; and others who smelt the old slags; from all of which they make +an ample return. + +Now a miner, before he begins to mine the veins, must consider seven +things, namely:--the situation, the conditions, the water, the roads, +the climate, the right of ownership, and the neighbours. There are four +kinds of situations--mountain, hill, valley, and plain. Of these four, +the first two are the most easily mined, because in them tunnels can be +driven to drain off the water, which often makes mining operations very +laborious, if it does not stop them altogether. The last two kinds of +ground are more troublesome, especially because tunnels cannot be driven +in such places. Nevertheless, a prudent miner considers all these four +sorts of localities in the region in which he happens to be, and he +searches for veins in those places where some torrent or other agency +has removed and swept the soil away; yet he need not prospect +everywhere, but since there is a great variety, both in mountains and in +the three other kinds of localities, he always selects from them those +which will give him the best chance of obtaining wealth. + +In the first place, mountains differ greatly in position, some being +situated in even and level plains, while others are found in broken and +elevated regions, and others again seem to be piled up, one mountain +upon another. The wise miner does not mine in mountains which are +situated on open plains, neither does he dig in those which are placed +on the summits of mountainous regions, unless by some chance the veins +in those mountains have been denuded of their surface covering, and +abounding in metals and other products, are exposed plainly to his +notice,--for with regard to what I have already said more than once, and +though I never repeat it again, I wish to emphasize this exception as to +the localities which should not be selected. All districts do not +possess a great number of mountains crowded together; some have but one, +others two, others three, or perhaps a few more. In some places there +are plains lying between them; in others the mountains are joined +together or separated only by narrow valleys. The miner should not dig +in those solitary mountains, dispersed through the plains and open +regions, but only in those which are connected and joined with others. +Then again, since mountains differ in size, some being very large, +others of medium height, and others more like hills than mountains, the +miner rarely digs in the largest or the smallest of them, but generally +only in those of medium size. Moreover, mountains have a great variety +of shapes; for with some the slopes rise gradually, while others, on the +contrary, are all precipitous; in some others the slopes are gradual on +one side, and on the other sides precipitous; some are drawn out in +length; some are gently curved; others assume different shapes. But the +miner may dig in all parts of them, except where there are precipices, +and he should not neglect even these latter if metallic veins are +exposed before his eyes. There are just as great differences in hills as +there are in mountains, yet the miner does not dig except in those +situated in mountainous districts, and even very rarely in those. It is +however very little to be wondered at that the hill in the Island of +Lemnos was excavated, for the whole is of a reddish-yellow colour, which +furnishes for the inhabitants that valuable clay so especially +beneficial to mankind[10]. In like manner, other hills are excavated if +chalk or other varieties of earth are exposed, but these are not +prospected for. + +There are likewise many varieties of valleys and plains. One kind is +enclosed on the sides with its outlet and entrance open; another has +either its entrance or its outlet open and the rest of it is closed in; +both of these are properly called valleys. There is a third variety +which is surrounded on all sides by mountains, and these are called +_convalles_. Some valleys again, have recesses, and others have none; +one is wide, another narrow; one is long, another short; yet another +kind is not higher than the neighbouring plain, and others are lower +than the surrounding flat country. But the miner does not dig in those +surrounded on all sides by mountains, nor in those that are open, unless +there be a low plain close at hand, or unless a vein of metal descending +from the mountains should extend into the valley. Plains differ from one +another, one being situated at low elevation, and others higher, one +being level and another with a slight incline. The miner should never +excavate the low-lying plain, nor one which is perfectly level, unless +it be in some mountain, and rarely should he mine in the other kinds of +plains. + +With regard to the conditions of the locality the miner should not +contemplate mining without considering whether the place be covered with +trees or is bare. If it be a wooded place, he who digs there has this +advantage, besides others, that there will be an abundant supply of wood +for his underground timbering, his machinery, buildings, smelting, and +other necessities. If there is no forest he should not mine there unless +there is a river near, by which he can carry down the timber. Yet +wherever there is a hope that pure gold or gems may be found, the ground +can be turned up, even though there is no forest, because the gems need +only to be polished and the gold to be purified. Therefore the +inhabitants of hot regions obtain these substances from rough and sandy +places, where sometimes there are not even shrubs, much less woods. + +The miner should next consider the locality, as to whether it has a +perpetual supply of running water, or whether it is always devoid of +water except when a torrent supplied by rains flows down from the +summits of the mountains. The place that Nature has provided with a +river or stream can be made serviceable for many things; for water will +never be wanting and can be carried through wooden pipes to baths in +dwelling-houses; it may be carried to the works, where the metals are +smelted; and finally, if the conditions of the place will allow it, the +water can be diverted into the tunnels, so that it may turn the +underground machinery. Yet on the other hand, to convey a constant +supply of water by artificial means to mines where Nature has denied it +access, or to convey the ore to the stream, increases the expense +greatly, in proportion to the distance the mines are away from the +river. + +The miner also should consider whether the roads from the neighbouring +regions to the mines are good or bad, short or long. For since a region +which is abundant in mining products very often yields no agricultural +produce, and the necessaries of life for the workmen and others must all +be imported, a bad and long road occasions much loss and trouble with +porters and carriers, and this increases the cost of goods brought in, +which, therefore, must be sold at high prices. This injures not so much +the workmen as the masters; since on account of the high price of goods, +the workmen are not content with the wages customary for their labour, +nor can they be, and they ask higher pay from the owners. And if the +owners refuse, the men will not work any longer in the mines but will go +elsewhere. Although districts which yield metals and other mineral +products are generally healthy, because, being often situated on high +and lofty ground, they are fanned by every wind, yet sometimes they are +unhealthy, as has been related in my other book, which is called "_De +Natura Eorum Quae Effluunt ex Terra_." Therefore, a wise miner does not +mine in such places, even if they are very productive, when he perceives +unmistakable signs of pestilence. For if a man mines in an unhealthy +region he may be alive one hour and dead the next. + +Then, the miner should make careful and thorough investigation +concerning the lord of the locality, whether he be a just and good man +or a tyrant, for the latter oppresses men by force of his authority, and +seizes their possessions for himself; but the former governs justly and +lawfully and serves the common good. The miner should not start mining +operations in a district which is oppressed by a tyrant, but should +carefully consider if in the vicinity there is any other locality +suitable for mining and make up his mind if the overlord there be +friendly or inimical. If he be inimical the mine will be rendered unsafe +through hostile attacks, in one of which all of the gold or silver, or +other mineral products, laboriously collected with much cost, will be +taken away from the owner and his workmen will be struck with terror; +overcome by fear, they will hastily fly, to free themselves from the +danger to which they are exposed. In this case, not only are the +fortunes of the miner in the greatest peril but his very life is in +jeopardy, for which reason he should not mine in such places. + +Since several miners usually come to mine the veins in one locality, a +settlement generally springs up, for the miner who began first cannot +keep it exclusively for himself. The _Bergmeister_ gives permits to some +to mine the superior and some the inferior parts of the veins; to some +he gives the cross veins, to others the inclined veins. If the man who +first starts work finds the vein to be metal-bearing or yielding other +mining products, it will not be to his advantage to cease work because +the neighbourhood may be evil, but he will guard and defend his rights +both by arms and by the law. When the _Bergmeister_[11] delimits the +boundaries of each owner, it is the duty of a good miner to keep within +his bounds, and of a prudent one to repel encroachments of his +neighbours by the help of the law. But this is enough about the +neighbourhood. + +The miner should try to obtain a mine, to which access is not difficult, +in a mountainous region, gently sloping, wooded, healthy, safe, and not +far distant from a river or stream by means of which he may convey his +mining products to be washed and smelted. This indeed, is the best +position. As for the others, the nearer they approximate to this +position the better they are; the further removed, the worse. + +Now I will discuss that kind of minerals for which it is not necessary +to dig, because the force of water carries them out of the veins. Of +these there are two kinds, minerals--and their fragments[12]--and +juices. When there are springs at the outcrop of the veins from which, +as I have already said, the above-mentioned products are emitted, the +miner should consider these first, to see whether there are metals or +gems mixed with the sand, or whether the waters discharged are filled +with juices. In case metals or gems have settled in the pool of the +spring, not only should the sand from it be washed, but also that from +the streams which flow from these springs, and even from the river +itself into which they again discharge. If the springs discharge water +containing some juice, this also should be collected; the further such a +stream has flowed from the source, the more it receives plain water and +the more diluted does it become, and so much the more deficient in +strength. If the stream receives no water of another kind, or scarcely +any, not only the rivers, but likewise the lakes which receive these +waters, are of the same nature as the springs, and serve the same uses; +of this kind is the lake which the Hebrews call the Dead Sea, and which +is quite full of bituminous fluids[13]. But I must return to the subject +of the sands. + +Springs may discharge their waters into a sea, a lake, a marsh, a river, +or a stream; but the sand of the sea-shore is rarely washed, for +although the water flowing down from the springs into the sea carries +some metals or gems with it, yet these substances can scarcely ever be +reclaimed, because they are dispersed through the immense body of waters +and mixed up with other sand, and scattered far and wide in different +directions, or they sink down into the depths of the sea. For the same +reasons, the sands of lakes can very rarely be washed successfully, even +though the streams rising from the mountains pour their whole volume of +water into them. The particles of metals and gems from the springs are +very rarely carried into the marshes, which are generally in level and +open places. Therefore, the miner, in the first place, washes the sand +of the spring, then of the stream which flows from it, then finally, +that of the river into which the stream discharges. It is not worth the +trouble to wash the sands of a large river which is on a level plain at +a distance from the mountains. Where several springs carrying metals +discharge their waters into one river, there is more hope of productive +results from washing. The miner does not neglect even the sands of the +streams in which excavated ores have been washed. + +The waters of springs taste according to the juice they contain, and +they differ greatly in this respect. There are six kinds of these tastes +which the worker[14] especially observes and examines; there is the +salty kind, which shows that salt may be obtained by evaporation; the +nitrous, which indicates soda; the aluminous kind, which indicates alum; +the vitrioline, which indicates vitriol; the sulphurous kind, which +indicates sulphur; and as for the bituminous juice, out of which bitumen +is melted down, the colour itself proclaims it to the worker who is +evaporating it. The sea-water however, is similar to that of salt +springs, and may be drawn into low-lying pits, and, evaporated by the +heat of the sun, changes of itself into salt; similarly the water of +some salt-lakes turns to salt when dried by the heat of summer. +Therefore an industrious and diligent man observes and makes use of +these things and thus contributes something to the common welfare. + +The strength of the sea condenses the liquid bitumen which flows into it +from hidden springs, into amber and jet, as I have described already in +my books "_De Subterraneorum Ortu et Causis_"[15]. The sea, with certain +directions of the wind, throws both these substances on shore, and for +this reason the search for amber demands as much care as does that for +coral. + +Moreover, it is necessary that those who wash the sand or evaporate the +water from the springs, should be careful to learn the nature of the +locality, its roads, its salubrity, its overlord, and the neighbours, +lest on account of difficulties in the conduct of their business they +become either impoverished by exhaustive expenditure, or their goods and +lives are imperilled. But enough about this. + +The miner, after he has selected out of many places one particular spot +adapted by Nature for mining, bestows much labour and attention on the +veins. These have either been stripped bare of their covering by chance +and thus lie exposed to our view, or lying deeply hidden and concealed +they are found after close search; the latter is more usual, the former +more rarely happens, and both of these occurrences must be explained. +There is more than one force which can lay bare the veins unaided by the +industry or toil of man; since either a torrent might strip off the +surface, which happened in the case of the silver mines of Freiberg +(concerning which I have written in Book I. of my work "_De Veteribus +et Novis Metallis_")[16]; or they may be exposed through the force of +the wind, when it uproots and destroys the trees which have grown over +the veins; or by the breaking away of the rocks; or by long-continued +heavy rains tearing away the mountain; or by an earthquake; or by a +lightning flash; or by a snowslide; or by the violence of the winds: "Of +such a nature are the rocks hurled down from the mountains by the force +of the winds aided by the ravages of time." Or the plough may uncover +the veins, for Justin relates in his history that nuggets of gold had +been turned up in Galicia by the plough; or this may occur through a +fire in the forest, as Diodorus Siculus tells us happened in the silver +mines in Spain; and that saying of Posidonius is appropriate enough: +"The earth violently moved by the fires consuming the forest sends forth +new products, namely, gold and silver."[17] And indeed, Lucretius has +explained the same thing more fully in the following lines: "Copper and +gold and iron were discovered, and at the same time weighty silver and +the substance of lead, when fire had burned up vast forests on the great +hills, either by a discharge of heaven's lightning, or else because, +when men were waging war with one another, forest fires had carried fire +among the enemy in order to strike terror to them, or because, attracted +by the goodness of the soil, they wished to clear rich fields and bring +the country into pasture, or else to destroy wild beasts and enrich +themselves with the game; for hunting with pitfalls and with fire came +into use before the practice of enclosing the wood with toils and +rousing the game with dogs. Whatever the fact is, from whatever cause +the heat of flame had swallowed up the forests with a frightful +crackling from their very roots, and had thoroughly baked the earth with +fire, there would run from the boiling veins and collect into the +hollows of the grounds a stream of silver and gold, as well as of copper +and lead."[18] But yet the poet considers that the veins are not laid +bare in the first instance so much by this kind of fire, but rather that +all mining had its origin in this. And lastly, some other force may by +chance disclose the veins, for a horse, if this tale can be believed, +disclosed the lead veins at Goslar by a blow from his hoof[19]. By such +methods as these does fortune disclose the veins to us. + +But by skill we can also investigate hidden and concealed veins, by +observing in the first place the bubbling waters of springs, which +cannot be very far distant from the veins because the source of the +water is from them; secondly, by examining the fragments of the veins +which the torrents break off from the earth, for after a long time some +of these fragments are again buried in the ground. Fragments of this +kind lying about on the ground, if they are rubbed smooth, are a long +distance from the veins, because the torrent, which broke them from the +vein, polished them while it rolled them a long distance; but if they +are fixed in the ground, or if they are rough, they are nearer to the +veins. The soil also should be considered, for this is often the cause +of veins being buried more or less deeply under the earth; in this case +the fragments protrude more or less widely apart, and miners are wont to +call the veins discovered in this manner "_fragmenta_."[20] + +Further, we search for the veins by observing the hoar-frosts, which +whiten all herbage except that growing over the veins, because the veins +emit a warm and dry exhalation which hinders the freezing of the +moisture, for which reason such plants appear rather wet than whitened +by the frost. This may be observed in all cold places before the grass +has grown to its full size, as in the months of April and May; or when +the late crop of hay, which is called the _cordum_, is cut with scythes +in the month of September. Therefore in places where the grass has a +dampness that is not congealed into frost, there is a vein beneath; also +if the exhalation be excessively hot, the soil will produce only small +and pale-coloured plants. Lastly, there are trees whose foliage in +spring-time has a bluish or leaden tint, the upper branches more +especially being tinged with black or with any other unnatural colour, +the trunks cleft in two, and the branches black or discoloured. These +phenomena are caused by the intensely hot and dry exhalations which do +not spare even the roots, but scorching them, render the trees sickly; +wherefore the wind will more frequently uproot trees of this kind than +any others. Verily the veins do emit this exhalation. Therefore, in a +place where there is a multitude of trees, if a long row of them at an +unusual time lose their verdure and become black or discoloured, and +frequently fall by the violence of the wind, beneath this spot there is +a vein. Likewise along a course where a vein extends, there grows a +certain herb or fungus which is absent from the adjacent space, or +sometimes even from the neighbourhood of the veins. By these signs of +Nature a vein can be discovered. + +There are many great contentions between miners concerning the forked +twig[21], for some say that it is of the greatest use in discovering +veins, and others deny it. Some of those who manipulate and use the +twig, first cut a fork from a hazel bush with a knife, for this bush +they consider more efficacious than any other for revealing the veins, +especially if the hazel bush grows above a vein. Others use a different +kind of twig for each metal, when they are seeking to discover the +veins, for they employ hazel twigs for veins of silver; ash twigs for +copper; pitch pine for lead and especially tin, and rods made of iron +and steel for gold. All alike grasp the forks of the twig with their +hands, clenching their fists, it being necessary that the clenched +fingers should be held toward the sky in order that the twig should be +raised at that end where the two branches meet. Then they wander hither +and thither at random through mountainous regions. It is said that the +moment they place their feet on a vein the twig immediately turns and +twists, and so by its action discloses the vein; when they move their +feet again and go away from that spot the twig becomes once more +immobile. + +The truth is, they assert, the movement of the twig is caused by the +power of the veins, and sometimes this is so great that the branches of +trees growing near a vein are deflected toward it. On the other hand, +those who say that the twig is of no use to good and serious men, also +deny that the motion is due to the power of the veins, because the twigs +will not move for everybody, but only for those who employ incantations +and craft. Moreover, they deny the power of a vein to draw to itself the +branches of trees, but they say that the warm and dry exhalations cause +these contortions. Those who advocate the use of the twig make this +reply to these objections: when one of the miners or some other person +holds the twig in his hands, and it is not turned by the force of a +vein, this is due to some peculiarity of the individual, which hinders +and impedes the power of the vein, for since the power of the vein in +turning and twisting the twig may be not unlike that of a magnet +attracting and drawing iron toward itself, this hidden quality of a man +weakens and breaks the force, just the same as garlic weakens and +overcomes the strength of a magnet. For a magnet smeared with garlic +juice cannot attract iron; nor does it attract the latter when rusty. +Further, concerning the handling of the twig, they warn us that we +should not press the fingers together too lightly, nor clench them too +firmly, for if the twig is held lightly they say that it will fall +before the force of the vein can turn it; if however, it is grasped too +firmly the force of the hands resists the force of the veins and +counteracts it. Therefore, they consider that five things are necessary +to insure that the twig shall serve its purpose: of these the first is +the size of the twig, for the force of the veins cannot turn too large a +stick; secondly, there is the shape of the twig, which must be forked or +the vein cannot turn it; thirdly, the power of the vein which has the +nature to turn it; fourthly, the manipulation of the twig; fifthly, the +absence of impeding peculiarities. These advocates of the twig sum up +their conclusions as follows: if the rod does not move for everybody, it +is due to unskilled manipulation or to the impeding peculiarities of the +man which oppose and resist the force of the veins, as we said above, +and those who search for veins by means of the twig need not necessarily +make incantations, but it is sufficient that they handle it suitably and +are devoid of impeding power; therefore, the twig may be of use to good +and serious men in discovering veins. With regard to deflection of +branches of trees they say nothing and adhere to their opinion. + +[Illustration 40 (Divining Rod): A--Twig. B--Trench.] + +Since this matter remains in dispute and causes much dissention amongst +miners, I consider it ought to be examined on its own merits. The +wizards, who also make use of rings, mirrors and crystals, seek for +veins with a divining rod shaped like a fork; but its shape makes no +difference in the matter,--it might be straight or of some other +form--for it is not the form of the twig that matters, but the wizard's +incantations which it would not become me to repeat, neither do I wish +to do so. The Ancients, by means of the divining rod, not only procured +those things necessary for a livelihood or for luxury, but they were +also able to alter the forms of things by it; as when the magicians +changed the rods of the Egyptians into serpents, as the writings of the +Hebrews relate[22]; and as in Homer, Minerva with a divining rod turned +the aged Ulysses suddenly into a youth, and then restored him back again +to old age; Circe also changed Ulysses' companions into beasts, but +afterward gave them back again their human form[23]; moreover by his +rod, which was called "Caduceus," Mercury gave sleep to watchmen and +awoke slumberers[24]. Therefore it seems that the divining rod passed to +the mines from its impure origin with the magicians. Then when good men +shrank with horror from the incantations and rejected them, the twig was +retained by the unsophisticated common miners, and in searching for new +veins some traces of these ancient usages remain. + +But since truly the twigs of the miners do move, albeit they do not +generally use incantations, some say this movement is caused by the +power of the veins, others say that it depends on the manipulation, and +still others think that the movement is due to both these causes. But, +in truth, all those objects which are endowed with the power of +attraction do not twist things in circles, but attract them directly to +themselves; for instance, the magnet does not turn the iron, but draws +it directly to itself, and amber rubbed until it is warm does not bend +straws about, but simply draws them to itself. If the power of the veins +were of a similar nature to that of the magnet and the amber, the twig +would not so much twist as move once only, in a semi-circle, and be +drawn directly to the vein, and unless the strength of the man who holds +the twig were to resist and oppose the force of the vein, the twig would +be brought to the ground; wherefore, since this is not the case, it must +necessarily follow that the manipulation is the cause of the twig's +twisting motion. It is a conspicuous fact that these cunning +manipulators do not use a straight twig, but a forked one cut from a +hazel bush, or from some other wood equally flexible, so that if it be +held in the hands, as they are accustomed to hold it, it turns in a +circle for any man wherever he stands. Nor is it strange that the twig +does not turn when held by the inexperienced, because they either grasp +the forks of the twig too tightly or hold them too loosely. +Nevertheless, these things give rise to the faith among common miners +that veins are discovered by the use of twigs, because whilst using +these they do accidentally discover some; but it more often happens that +they lose their labour, and although they might discover a vein, they +become none the less exhausted in digging useless trenches than do the +miners who prospect in an unfortunate locality. Therefore a miner, since +we think he ought to be a good and serious man, should not make use of +an enchanted twig, because if he is prudent and skilled in the natural +signs, he understands that a forked stick is of no use to him, for as I +have said before, there are the natural indications of the veins which +he can see for himself without the help of twigs. So if Nature or chance +should indicate a locality suitable for mining, the miner should dig his +trenches there; if no vein appears he must dig numerous trenches until +he discovers an outcrop of a vein. + +A _vena dilatata_ is rarely discovered by men's labour, but usually some +force or other reveals it, or sometimes it is discovered by a shaft or a +tunnel on a _vena profunda_[25]. + +The veins after they have been discovered, and likewise the shafts and +tunnels, have names given them, either from their discoverers, as in the +case at Annaberg of the vein called "Kölergang," because a charcoal +burner discovered it; or from their owners, as the Geyer, in +Joachimsthal, because part of the same belonged to Geyer; or from their +products, as the "Pleygang" from lead, or the "Bissmutisch" at +Schneeberg from bismuth[26]; or from some other circumstances, such as +the rich alluvials from the torrent by which they were laid bare in the +valley of Joachim. More often the first discoverers give the names +either of persons, as those of German Kaiser, Apollo, Janus; or the name +of an animal, as that of lion, bear, ram, or cow; or of things +inanimate, as "silver chest" or "ox stalls"; or of something ridiculous, +as "glutton's nightshade"; or finally, for the sake of a good omen, they +call it after the Deity. In ancient times they followed the same custom +and gave names to the veins, shafts and tunnels, as we read in Pliny: +"It is wonderful that the shafts begun by Hannibal in Spain are still +worked, their names being derived from their discoverers. One of these +at the present day, called Baebelo, furnished Hannibal with three +hundred pounds weight (of silver) per day."[27] + + END OF BOOK II. + + +FOOTNOTES: + +[1] Xenophon. Essay on the Revenues of Athens, IV., 14. + +"But we cannot but feel surprised that the State, when it sees many +private individuals enriching themselves from its resources, does not +imitate their proceedings; for we heard long ago, indeed, at least such +of us as attended to these matters, that Nicias the son of Niceratus +kept a thousand men employed in the silver mines, whom he let on hire to +Sosias of Thrace on condition that he should give him for each an obolus +a day, free of all charges; and this number he always supplied +undiminished." (See also Note 6). An obolus a day each, would be about +23 oz. Troy of silver per day for the whole number. In modern value this +would, of course, be but about 50s. per day, but in purchasing power the +value would probably be 100 to 1 (see Note on p. 28). Nicias was +estimated to have a fortune of 100 talents--about 83,700 Troy ounces of +silver, and was one of the wealthiest of the Athenians. (Plutarch, Life +of Nicias). + +[2] Xenophon. _Oeconomicus_ XII., 20. "'I approve,' said Ischomachus, +'of the barbarian's answer to the King who found a good horse, and, +wishing to fatten it as soon as possible, asked a man with a good +reputation for horsemanship what would do it?' The man's reply was: 'Its +master's eye.'" + +[3] _Praefectus Metallorum._ In Saxony this official was styled the +_Berghauptmann_. For further information see page 94 and note on page +78. + +[4] This statement is either based upon Apollodorus, whom Agricola does +not mention among his authorities, or on Strabo, whom he does so +include. The former in his work on Mythology makes such a statement, for +which Strabo (XIV., 5, 28) takes him to task as follows: "With this vain +intention they collected the stories related by the Scepsian +(Demetrius), and taken from Callisthenes and other writers, who did not +clear them from false notions respecting the Halizones; for example, +that the wealth of Tantalus and of the Pelopidae was derived, it is +said, from the mines about Phrygia and Sipylus; that of Cadmus from the +mines of Thrace and Mount Pangaeum; that of Priam from the gold mines of +Astyra, near Abydos (of which at present there are small remains, yet +there is a large quantity of matter ejected, and the excavations are +proofs of former workings); that of Midas from the mines about Mount +Bermium; that of Gyges, Alyattes, and Croesus, from the mines in Lydia +and the small deserted city between Atarneus and Pergamum, where are the +sites of exhausted mines." (Hamilton's Trans., Vol. III., p. 66). + +In adopting this view, Agricola apparently applied a wonderful realism +to some Greek mythology--for instance, in the legend of Midas, which +tells of that king being rewarded by the god Dionysus, who granted his +request that all he touched might turn to gold; but the inconvenience of +the gift drove him to pray for relief, which he obtained by bathing in +the Pactolus, the sands of which thereupon became highly auriferous. +Priam was, of course, King of Troy, but Homer does not exhibit him as a +mine-owner. Gyges, Alyattes, and Croesus were successively Kings of +Lydia, from 687 to 546 B.C., and were no doubt possessed of great +treasure in gold. Some few years ago we had occasion to inquire into +extensive old workings locally reputed to be Croesus' mines, at a place +some distance north of Smyrna, which would correspond very closely to +the locality here mentioned. + +[5] There can be no doubt that the Carthaginians worked the mines of +Spain on an extensive scale for a very long period anterior to their +conquest by the Romans, but whether the mines were worked by the +Government or not we are unable to find any evidence. + +[6] The silver mines of Mt. Laurion formed the economic mainstay of +Athens for the three centuries during which the State had the ascendency +in Greece, and there can be no doubt that the dominance of Athens and +its position as a sea-power were directly due to the revenues from the +mines. The first working of the mines is shrouded in mystery. The +scarcity of silver in the time of Solon (638-598 B.C.) would not +indicate any very considerable output at that time. According to +Xenophon (Essay on Revenue of Athens, IV., 2), written about 355 B.C., +"they were wrought in very ancient times." The first definite discussion +of the mines in Greek record begins about 500 B.C., for about that time +the royalties began to figure in the Athenian Budget (Aristotle, +Constitution of Athens, 47). There can be no doubt that the mines +reached great prosperity prior to the Persian invasion. In the year 484 +B.C. the mines returned 100 Talents (about 83,700 oz. Troy) to the +Treasury, and this, on the advice of Themistocles, was devoted to the +construction of the fleet which conquered the Persians at Salamis (480 +B.C.). The mines were much interfered with by the Spartan invasions from +431 to 425 B.C., and again by their occupation in 413 B.C.; and by 355 +B.C., when Xenophon wrote the "Revenues," exploitation had fallen to a +low ebb, for which he proposes the remedies noted by Agricola on p. 28. +By the end of the 4th Century, B.C., the mines had again reached +considerable prosperity, as is evidenced by Demosthenes' orations +against Pantaenetus and against Phaenippus, and by Lycurgus' prosecution +of Diphilos for robbing the supporting pillars. The domination of the +Macedonians under Philip and Alexander at the end of the 4th and +beginning of the 3rd Centuries B.C., however, so flooded Greece with +money from the mines of Thrace, that this probably interfered with +Laurion, at this time, in any event, began the decadence of these mines. +Synchronous also was the decadence of Athens, and, but for fitful +displays, the State was not able to maintain even its own independence, +not to mention its position as a dominant State. Finally, Strabo, +writing about 30 B.C. gives the epitaph of every mining +district--reworking the dumps. He says (IX., 1, 23): "The silver mines +in Attica were at first of importance, but are now exhausted. The +workmen, when the mines yielded a bad return to their labour, committed +to the furnace the old refuse and scoria, and hence obtained very pure +silver, for the former workmen had carried on the process in the furnace +unskilfully." + +Since 1860, the mines have been worked with some success by a French +Company, thus carrying the mining history of this district over a period +of twenty-seven centuries. The most excellent of many memoirs upon the +mines at Laurion, not only for its critical, historical, and +archæological value, but also because of its author's great insight into +mining and metallurgy, is that of Edouard Ardaillon (_Les Mines du +Laurion dans l'Antiquité_, Paris, 1897). We have relied considerably +upon this careful study for the following notes, and would refer others +to it for a short bibliography on the subject. We would mention in +passing that Augustus Boeckh's "Silver Mines of Laurion," which is +incorporated with his "Public Economy of Athens" (English Translation by +Lewis, London, 1842) has been too much relied upon by English students. +It is no doubt the product of one acquainted with written history, but +without any special knowledge of the industry and it is based on no +antiquarian research. The Mt. Laurion mining district is located near +the southern end of the Attic Peninsula. The deposits are silver-lead, +and they occur along the contact between approximately horizontal +limestones and slates. There are two principal beds of each, thus +forming three principal contacts. The most metalliferous of these +contacts are those at the base of the slates, the lowest contact of the +series being the richest. The ore-bodies were most irregular, varying +greatly in size, from a thin seam between schist planes, to very large +bodies containing as much as 200,000 cubic metres. The ores are +argentiferous galena, accompanied by considerable amounts of blende and +pyrites, all oxidized near the surface. The ores worked by the Ancients +appear to have been fairly rich in lead, for the discards worked in +recent years by the French Company, and the pillars left behind, ran 8% +to 10% lead. The ratio of silver was from 40 to 90 ounces per ton of +lead. The upper contacts were exposed by erosion and could be entered by +tunnels, but the lowest and most prolific contact line was only to be +reached by shafts. The shafts were ordinarily from four to six feet +square, and were undoubtedly cut by hammer and chisel; they were as much +as 380 feet deep. In some cases long inclines for travelling roads join +the vertical shafts in depth. The drives, whether tunnels or from +shafts, were not level, but followed every caprice of the sinuous +contact. They were from two to two and a half feet wide, often driven in +parallels with cross-cuts between, in order to exploit every corner of +the contact. The stoping of ore-bodies discovered was undertaken quite +systematically, the methods depending in the main on the shape of the +ore-body. If the body was large, its dimensions were first determined by +drives, crosscuts, rises, and winzes, as the case might require. If the +ore was mainly overhead it was overhand-stoped, and the stopes filled as +work progressed, inclined winzes being occasionally driven from the +stopes to the original entry drives. If the ore was mainly below, it was +underhand-stoped, pillars being left if necessary--such pillars in some +cases being thirty feet high. They also employed timber and artificial +pillars. The mines were practically dry. There is little evidence of +breaking by fire. The ore was hand-sorted underground and carried out by +the slaves, and in some cases apparently the windlass was used. It was +treated by grinding in mills and concentrating upon a sort of buddle. +These concentrates--mostly galena--were smelted in low furnaces and the +lead was subsequently cupelled. Further details of metallurgical methods +will be found in Notes on p. 391 and p. 465, on metallurgical subjects. + +The mines were worked by slaves. Even the overseers were at times +apparently slaves, for we find (Xenophon, _Memorabilia_, II., 5) that +Nicias paid a whole talent for a good overseer. A talent would be about +837 Troy ounces of silver. As wages of skilled labour were about two and +one half pennyweights of silver per diem, and a family income of 100 +ounces of silver per annum was affluence, the ratio of purchasing power +of Attic coinage to modern would be about 100 to 1. Therefore this mine +manager was worth in modern value roughly £8,000. The mines were the +property of the State. The areas were defined by vertical boundaries, +and were let on lease for definite periods for a fixed annual rent. More +ample discussion of the law will be found on p. 83. + +[7] Xenophon. (Essay on The Revenues, IV., 30). "I think, however, that +I am able to give some advice with regard to this difficulty also (the +risk of opening new mines), and to show how new operations may be +conducted with the greatest safety. There are ten tribes at Athens, and +if to each of these the State should assign an equal number of slaves, +and the tribes should all make new cuttings, sharing their fortunes in +common, then if but one tribe should make any useful discovery it would +point out something profitable to the whole; but if two, three, or four, +or half the number should make some discovery, it is plain that the +works would be more profitable in proportion, and that they should all +fail is contrary to all experience in past times." (Watson's Trans. p. +258). + +[8] Agricola here refers to the proposal of Xenophon for the State to +collect slaves and hire them to work the mines of Laurion. There is no +evidence that this recommendation was ever carried out. + +[9] _Partes._ Agricola, p. 89-91, describes in detail the organization +and management of these share companies. See Note 8, p. 90. + +[10] This island in the northern Ægean Sea has produced this "earth" +from before Theophrastus' time (372-287 B.C.) down to the present day. +According to Dana (System of Mineralogy 689), it is cimolite, a hydrous +silicate of aluminium. The Ancients distinguished two kinds,--one sort +used as a pigment, and the other for medicinal purposes. This latter was +dug with great ceremony at a certain time of the year, moulded into +cubes, and stamped with a goat,--the symbol of Diana. It thus became +known as _terra sigillata_, and was an article of apothecary commerce +down to the last century. It is described by Galen (XII., 12), +Dioscorides (V., 63), and Pliny (XXXV., 14), as a remedy for ulcers and +snake bites. + +[11] _Magister Metallorum_. See Note 1, p. 78, for the reasons of the +adoption of the term _Bergmeister_ and page 95 for details of his +duties. + +[12] _Ramenta_. "Particles." The author uses this term indifferently for +fragments, particles of mineral, concentrates, gold dust, black tin, +etc., in all cases the result of either natural or artificial +concentration. As in technical English we have no general term for both +natural and artificial "concentrates," we have rendered it as the +context seemed to demand. + +[13] A certain amount of bitumen does float ashore in the Dead Sea; the +origin of it is, however, uncertain. Strabo (XVI., 2, 42), Pliny (V., 15 +and 16), and Josephus (IV., 8), all mention this fact. The lake for this +reason is often referred to by the ancient writers by the name +_Asphaltites_. + +[14] _Excoctor_,--literally, "Smelter" or "Metallurgist." + +[15] This reference should be to the _De Natura Fossilium_ (p. 230), +although there is a short reference to the matter in _De Ortu et Causis_ +(p. 59). Agricola maintained that not only were jet and amber varieties +of bitumen, but also coal and camphor and obsidian. As jet (_gagates_) +is but a compact variety of coal, the ancient knowledge of this +substance has more interest than would otherwise attach to the gem, +especially as some materials described in this connection were no doubt +coal. The Greeks often refer to a series of substances which burned, +contained earth, and which no doubt comprised coal. Such substances are +mentioned by Aristotle (_De Mirabilibus_. 33, 41, 125), Nicander +(_Theriaca_. 37), and others, previous to the 2nd Century B.C., but the +most ample description is that of Theophrastus (23-28): "Some of the +more brittle stones there also are, which become as it were burning +coals when put into a fire, and continue so a long time; of this kind +are those about Bena, found in mines and washed down by the torrents, +for they will take fire on burning coals being thrown on them, and will +continue burning as long as anyone blows them; afterward they will +deaden, and may after that be made to burn again. They are therefore of +long continuance, but their smell is troublesome and disagreeable. That +also which is called the _spinus_, is found in mines. This stone, cut in +pieces and thrown together in a heap, exposed to the sun, burns; and +that the more, if it be moistened or sprinkled with water (a +pyritiferous shale?). But the _Lipara_ stone empties itself, as it were, +in burning, and becomes like the _pumice_, changing at once both its +colour and density; for before burning it is black, smooth, and compact. +This stone is found in the Pumices, separately in different places, as +it were, in cells, nowhere continuous to the matter of them. It is said +that in Melos the pumice is produced in this manner in some other stone, +as this is on the contrary in it; but the stone which the pumice is +found in is not at all like the _Lipara_ stone which is found in it. +Certain stones there are about Tetras, in Sicily, which is over against +Lipara, which empty themselves in the same manner in the fire. And in +the promontory called Erineas, there is a great quantity of stone like +that found about Bena, which, when burnt, emits a bituminous smell, and +leaves a matter resembling calcined earth. Those fossil substances that +are called coals, and are broken for use, are earthy; they kindle, +however, and burn like wood coals. These are found in Liguria, where +there also is amber, and in Elis, on the way to Olympia over the +mountains. These are used by smiths." (Based on Hill's Trans.). +Dioscorides and Pliny add nothing of value to this description. + +Agricola (_De Nat. Fos._, p. 229-230) not only gives various localities +of jet, but also records its relation to coal. As to the latter, he +describes several occurrences, and describes the deposits as _vena +dilatata_. Coal had come into considerable use all over Europe, +particularly in England, long before Agricola's time; the oft-mentioned +charter to mine sea-coal given to the Monks of Newbottle Abbey, near +Preston, was dated 1210. + +Amber was known to the Greeks by the name _electrum_, but whether the +alloy of the same name took its name from the colour of amber or _vice +versa_ is uncertain. The gum is supposed to be referred to by Homer (Od. +XV. 460), and Thales of Miletus (640-546 B.C.) is supposed to have first +described its power of attraction. It is mentioned by many other Greek +authors, Æschylus, Euripides, Aristotle, and others. The latter (_De +Mirabilibus_, 81) records of the amber islands in the Adriatic, that the +inhabitants tell the story that on these islands amber falls from poplar +trees. "This, they say, resembles gum and hardens like stone, the story +of the poets being that after Phaeton was struck by lightning his +sisters turned to poplar trees and shed tears of amber." Theophrastus +(53) says: "Amber is also a stone; it is dug out of the earth in Liguria +and has, like the before-mentioned (lodestone), a power of attraction." +Pliny (XXXVII., 11) gives a long account of both the substance, +literature, and mythology on the subject. His view of its origin was: +"Certainly amber is obtained from the islands of the Northern Ocean, and +is called by the Germans _glaesum_. For this reason the Romans, when +Germanicus Cæsar commanded in those parts, called one of them +_Glaesaria_, which was known to the barbarians as _Austeravia_. Amber +originates from gum discharged by a kind of pine tree, like gum from +cherry and resin from the ordinary pine. It is liquid at first, and +issues abundantly and hardens in time by cold, or by the sea when the +rising tides carry off the fragments from the shores of those islands. +Certainly it is thrown on the coasts, and is so light that it appears to +roll in the water. Our forefathers believed that it was the juice of a +tree, for they called it _succinum_. And that it belongs to a kind of +pine tree is proved by the odour of the pine tree which it gives when +rubbed, and that it burns when ignited like a pitch pine torch." The +term amber is of Arabic origin--from _Ambar_--and this term was adopted +by the Greeks after the Christian era. Agricola uses the Latin term +_succinum_ and (_De Nat. Fos._, p. 231-5) disputes the origin from tree +gum, and contends for submarine bitumen springs. + +[16] The statement in _De Veteribus et Novis Metallis_ (p. 394) is as +follows:-- + +"It came about by chance and accident that the silver mines were +discovered at Freiberg in Meissen. By the river Sala, which is not +unknown to Strabo, is Hala, which was once country, but is now a large +town; the site, at any rate, even from Roman times was famous and +renowned for its salt springs, for the possession of which the +Hermunduri fought with the Chatti. When people carried the salt thence +in wagons, as they now do straight through Meissen (Saxony) into +Bohemia--which is lacking in that seasoning to-day no less than +formerly--they saw galena in the wheel tracks, which had been uncovered +by the torrents. This lead ore, since it was similar to that of Goslar, +they put into their carts and carried to Goslar, for the same carriers +were accustomed to carry lead from that city. And since much more silver +was smelted from this galena than from that of Goslar, certain miners +betook themselves to that part of Meissen in which is now situated +Freiberg, a great and wealthy town; and we are told by consistent +stories and general report that they grew rich out of the mines." +Agricola places the discovery of the mines at Freiberg at about 1170. +See Note 11, p. 5. + +[17] Diodorus Siculus (V., 35). "These places being covered with woods, +it is said that in ancient times these mountains were set on fire by +shepherds, and continued burning for many days, and parched the earth, +so that an abundance of silver ore was melted, and the metal flowed in +streams of pure silver like a river." Aristotle, nearly three centuries +before Diodorus, mentions this same story (_De Mirabilibus_, 87): "They +say that in Ibernia the woods were set on fire by certain shepherds, and +the earth thus heated, the country visibly flowed silver; and when some +time later there were earthquakes, and the earth burst asunder at +different places, a large amount of silver was collected." As the works +of Posidonius are lost, it is probable that Agricola was quoting from +Strabo (III., 2, 9), who says, in describing Spain: "Posidonius, in +praising the amount and excellence of the metals, cannot refrain from +his accustomed rhetoric, and becomes quite enthusiastic in exaggeration. +He tells us we are not to disbelieve the fable that formerly the forests +having been set on fire, the earth, which was loaded with silver and +gold, melted and threw up these metals to the surface, for inasmuch as +every mountain and wooded hill seemed to be heaped up with money by a +lavish fortune." (Hamilton's Trans. I., p. 220). Or he may have been +quoting from the _Deipnosophistae_ of Athenaeus (VI.), where Posidonius +is quoted: "And the mountains ... when once the woods upon them had +caught fire, spontaneously ran with liquid silver." + +[18] Lucretius, _De Rerum Natura_ V. 1241. + +[19] Agricola's account of this event in _De Veteribus et Novis +Metallis_ is as follows (p. 393): "Now veins are not always first +disclosed by the hand and labour of man, nor has art always demonstrated +them; sometimes they have been disclosed rather by chance or by good +fortune. I will explain briefly what has been written upon this matter +in history, what miners tell us, and what has occurred in our times. +Thus the mines at Goslar are said to have been found in the following +way. A certain noble, whose name is not recorded, tied his horse, which +was named Ramelus, to the branch of a tree which grew on the mountain. +This horse, pawing the earth with its hoofs, which were iron shod, and +thus turning it over, uncovered a hidden vein of lead, not unlike the +winged Pegasus, who in the legend of the poets opened a spring when he +beat the rock with his hoof. So just as that spring is named Hippocrene +after that horse, so our ancestors named the mountain Rammelsberg. +Whereas the perennial water spring of the poets would long ago have +dried up, the vein even to-day exists, and supplies an abundant amount +of excellent lead. That a horse can have opened a vein will seem +credible to anyone who reflects in how many ways the signs of veins are +shown by chance, all of which are explained in my work _De Re +Metallica_. Therefore, here we will believe the story, both because it +may happen that a horse may disclose a vein, and because the name of the +mountain agrees with the story." Agricola places the discovery of Goslar +in the Hartz at prior to 936. See Note 11, p. 5. + +[20] _Fragmenta_. The glossary gives "_Geschube_." This term is defined +in the _Bergwerks' Lexicon_ (Chemnitz, 1743, p. 250) as the pieces of +stone, especially tin-stone, broken from the vein and washed out by the +water--the croppings. + +[21] So far as we are able to discover, this is the first published +description of the divining rod as applied to minerals or water. Like +Agricola, many authors have sought to find its origin among the +Ancients. The magic rods of Moses and Homer, especially the rod with +which the former struck the rock at Horeb, the rod described by Ctesias +(died 398 B.C.) which attracted gold and silver, and the _virgula +divina_ of the Romans have all been called up for proof. It is true that +the Romans are responsible for the name _virgula divina_, "divining +rod," but this rod was used for taking auguries by casting bits of wood +(Cicero, _De Divinatione_). Despite all this, while the ancient +naturalists all give detailed directions for finding water, none mention +anything akin to the divining rod of the Middle Ages. It is also worth +noting that the Monk Theophilus in the 12th Century also gives a +detailed description of how to find water, but makes no mention of the +rod. There are two authorities sometimes cited as prior to Agricola, the +first being Basil Valentine in his "Last Will and Testament" +(XXIV-VIII.), and while there may be some reason (see Appendix) for +accepting the authenticity of the "Triumphal Chariot of Antimony" by +this author, as dating about 1500, there can be little doubt that the +"Last Will and Testament" was spurious and dated about 50 years after +Agricola. Paracelsus (_De Natura Rerum_ IX.), says: "These (divinations) +are vain and misleading, and among the first of them are divining rods, +which have deceived many miners. If they once point rightly they deceive +ten or twenty times." In his _De Origine Morborum Invisibilium_ (Book +I.) he adds that the "faith turns the rod." These works were no doubt +written prior to _De Re Metallica_--Paracelsus died in 1541--but they +were not published until some time afterward. Those interested in the +strange persistence of this superstition down to the present day--and +the files of the patent offices of the world are full of it--will find +the subject exhaustively discussed in M. E. Chevreul's "_De la Baguette +Divinatoire_," Paris, 1845; L. Figuier, "_Histoire du Merveilleux dans +les temps moderne II._", Paris, 1860; W. F. Barrett, Proceedings of the +Society of Psychical Research, part 32, 1897, and 38, 1900; R. W. +Raymond, American Inst. of Mining Engineers, 1883, p. 411. Of the +descriptions by those who believed in it there is none better than that +of William Pryce (_Mineralogia Cornubiensis_, London, 1778, pp. +113-123), who devotes much pains to a refutation of Agricola. When we +consider that a century later than Agricola such an advanced mind as +Robert Boyle (1626-1691), the founder of the Royal Society, was +convinced of the genuineness of the divining rod, one is more impressed +with the clarity of Agricola's vision. In fact, there were few indeed, +down to the 19th Century, who did not believe implicitly in the +effectiveness of this instrument, and while science has long since +abandoned it, not a year passes but some new manifestation of its hold +on the popular mind breaks out. + +[22] Exodus VII., 10, 11, 12. + +[23] Odyssey XVI., 172, and X., 238. + +[24] Odyssey XXIV., 1, etc. The _Caduceus_ of Hermes had also the power +of turning things to gold, and it is interesting to note that in its +oldest form, as the insignia of heralds and of ambassadors, it had two +prongs. + +[25] In a general way _venae profundae_ were fissure veins and _venae +dilatatae_ were sheeted deposits. For description see Book III. + +[26] These mines are in the Erzgebirge. We have adopted the names given +in the German translation. + +[27] The quotation from Pliny (XXXIII., 31) as a whole reads as +follows:-- + +"Silver is found in nearly all the provinces, but the finest of all in +Spain; where it is found in the barren lands, and in the mountains. +Wherever one vein of silver has been found, another is sure to be found +not far away. This is the case of nearly all the metals, whence it +appears that the Greeks derived _metalla_. It is wonderful that the +shafts begun by Hannibal in Spain still remain, their names being +derived from their makers. One of these at the present day called +Baebelo, furnished Hannibal with three hundred pounds' weight (of +silver) per day. This mountain is excavated for a distance of fifteen +hundred paces; and for this distance there are waterbearers lighted by +torches standing night and day baling out the water in turns, thus +making quite a river." Hannibal dates 247-183 B.C. and was therefore +dead 206 years when Pliny was born. According to a footnote in Bostock +and Riley's translation of Pliny, these workings were supposed to be in +the neighbourhood of Castulo, now Cazlona, near Linares. It was at +Castulo that Hannibal married his rich wife Himilce; and in the hills +north of Linares there are ancient silver mines still known as Los Pozos +de Anibal. + + + + +BOOK III. + + +Previously I have given much information concerning the miners, also I +have discussed the choice of localities for mining, for washing sands, +and for evaporating waters; further, I described the method of searching +for veins. With such matters I was occupied in the second book; now I +come to the third book, which is about veins and stringers, and the +seams in the rocks[1]. The term "vein" is sometimes used to indicate +_canales_ in the earth, but very often elsewhere by this name I have +described that which may be put in vessels[2]; I now attach a second +significance to these words, for by them I mean to designate any mineral +substances which the earth keeps hidden within her own deep receptacles. + +[Illustration 45a (Vein in mountain): A, C--The mountain. B--_Vena +profunda_.] + +First I will speak of the veins, which, in depth, width, and length, +differ very much one from another. Those of one variety descend from the +surface of the earth to its lowest depths, which on account of this +characteristic, I am accustomed to call "_venae profundae_." + +[Illustration 45b (Vein in mountain): A, D--The mountain. B, C--_Vena +dilatata_.] + +Another kind, unlike the _venae profundae_, neither ascend to the +surface of the earth nor descend, but lying under the ground, expand +over a large area; and on that account I call them "_venae dilatatae_." + +[Illustration 49 (Veins in mountain): A, B, C, D--The mountain. E, F, G, +H, I, K--_Vena cumulata_.] + +Another occupies a large extent of space in length and width; therefore +I usually call it "_vena cumulata_," for it is nothing else than an +accumulation of some certain kind of mineral, as I have described in the +book entitled _De Subterraneorum Ortu et Causis_. It occasionally +happens, though it is unusual and rare, that several accumulations of +this kind are found in one place, each one or more fathoms in depth and +four or five in width, and one is distant from another two, three, or +more fathoms. When the excavation of these accumulations begins, they at +first appear in the shape of a disc; then they open out wider; finally +from each of such accumulations is usually formed a "_vena cumulata_." + +[Illustration 50a (Veins in mountain): A--_Vena profunda_. +B--_Intervenium_. C--Another _vena profunda_.] + +[Illustration 50b (Veins in mountain): A & B--_Vena dilatatae_. +C--_Intervenium_. D & E--Other _venae dilatatae_.] + +The space between two veins is called an _intervenium_; this interval +between the veins, if it is between _venae dilatatae_ is entirely hidden +underground. If, however, it lies between _venae profundae_ then the top +is plainly in sight, and the remainder is hidden. + +[Illustration 53 (Veins in mountain): A--Wide _vena profunda_. +B--Narrow _vena profunda_.] + +_Venae profundae_ differ greatly one from another in width, for some of +them are one fathom wide, some are two cubits, others one cubit; others +again are a foot wide, and some only half a foot; all of which our +miners call wide veins. Others on the contrary, are only a palm wide, +others three digits, or even two; these they call narrow. But in other +places where there are very wide veins, the widths of a cubit, or a +foot, or half a foot, are said to be narrow; at Cremnitz, for instance, +there is a certain vein which measures in one place fifteen fathoms in +width, in another eighteen, and in another twenty; the truth of this +statement is vouched for by the inhabitants. + +[Illustration 54a (Veins in mountain): A--Thin _vena dilatata_. +B--Thick _vena dilatata_.] + +_Venae dilatatae_, in truth, differ also in thickness, for some are one +fathom thick, others two, or even more; some are a cubit thick, some a +foot, some only half a foot; and all these are usually called thick +veins. Some on the other hand, are but a palm thick, some three digits, +some two, some one; these are called thin veins. + +[Illustration 54b (Seams in the Rocks): A, B, C--Vein. D, E, F--Seams in +the Rock (_Commissurae Saxorum_).] + +_Venae profundae_ vary in direction; for some run from east to west. + +[Illustration 55a (Seams in the Rocks): A, B, C--Vein. D, E, F--_Seams in +the Rocks_.] + +Others, on the other hand, run from west to east. + +[Illustration 55b (Seams in the Rocks): A, B, C--Vein. D, E, F--_Seams in +the Rocks_.] + +Others run from south to north. + +[Illustration 56 (Seams in the Rocks): A, B, C--Vein. D, E, F--_Seams in +the Rocks_.] + +Others, on the contrary, run from north to south. + +The seams in the rocks indicate to us whether a vein runs from the east +or from the west. For instance, if the rock seams incline toward the +westward as they descend into the earth, the vein is said to run from +east to west; if they incline toward the east, the vein is said to run +from west to east; in a similar manner, we determine from the rock seams +whether the veins run north or south. + +[Illustration 57 (Compass)] + +Now miners divide each quarter of the earth into six divisions; and by +this method they apportion the earth into twenty-four directions, which +they divide into two parts of twelve each. The instrument which +indicates these directions is thus constructed. First a circle is made; +then at equal intervals on one half portion of it right through to the +other, twelve straight lines called by the Greeks [Greek: diametroi], +and in the Latin _dimetientes_, are drawn through a central point which +the Greeks call [Greek: kentron], so that the circle is thus divided +into twenty-four divisions, all being of an equal size. Then, within the +circle are inscribed three other circles, the outermost of which has +cross-lines dividing it into twenty-four equal parts; the space between +it and the next circle contains two sets of twelve numbers, inscribed on +the lines called "diameters"; while within the innermost circle it is +hollowed out to contain a magnetic needle[3]. The needle lies directly +over that one of the twelve lines called "diameters" on which the +number XII is inscribed at both ends. + +When the needle which is governed by the magnet points directly from the +north to the south, the number XII at its tail, which is forked, +signifies the north, that number XII which is at its point indicates the +south. The sign VI superior indicates the east, and VI inferior the +west. Further, between each two cardinal points there are always five +others which are not so important. The first two of these directions are +called the prior directions; the last two are called the posterior, and +the fifth direction lies immediately between the former and the latter; +it is halved, and one half is attributed to one cardinal point and one +half to the other. For example, between the northern number XII and the +eastern number VI, are points numbered I, II, III, IV, V, of which I and +II are northern directions lying toward the east, IV and V are eastern +directions lying toward the north, and III is assigned, half to the +north and half to the east. + +One who wishes to know the direction of the veins underground, places +over the vein the instrument just described; and the needle, as soon as +it becomes quiet, will indicate the course of the vein. That is, if the +vein proceeds from VI to VI, it either runs from east to west, or from +west to east; but whether it be the former or the latter, is clearly +shown by the seams in the rocks. If the vein proceeds along the line +which is between V and VI toward the opposite direction, it runs from +between the fifth and sixth divisions of east to the west, or from +between the fifth and sixth divisions of west to the east; and again, +whether it is the one or the other is clearly shown by the seams in the +rocks. In a similar manner we determine the other directions. + +[Illustration 59 (Compass with winds)] + +Now miners reckon as many points as the sailors do in reckoning up the +number of the winds. Not only is this done to-day in this country, but +it was also done by the Romans who in olden times gave the winds partly +Latin names and partly names borrowed from the Greeks. Any miner who +pleases may therefore call the directions of the veins by the names of +the winds. There are four principal winds, as there are four cardinal +points: the _Subsolanus_, which blows from the east; and its opposite +the _Favonius_, which blows from the west; the latter is called by the +Greeks [Greek: Zephyros], and the former [Greek: Apêliôtês]. There is +the _Auster_, which blows from the south; and opposed to it is the +_Septentrio_, from the north; the former the Greeks called [Greek: +Notos], and the latter [Greek: Aparktias]. There are also subordinate +winds, to the number of twenty, as there are directions, for between +each two principal winds there are always five subordinate ones. Between +the _Subsolanus_ (east wind) and the _Auster_ (south wind) there is the +_Ornithiae_ or the Bird wind, which has the first place next to the +_Subsolanus_; then comes _Caecias_; then _Eurus_, which lies in the +midway of these five; next comes _Vulturnus_; and lastly, _Euronotus_, +nearest the _Auster_ (south wind). The Greeks have given these names to +all of these, with the exception of _Vulturnus_, but those who do not +distinguish the winds in so precise a manner say this is the same as the +Greeks called [Greek: Euros]. Between the _Auster_ (south wind) and the +_Favonius_ (west wind) is first _Altanus_, to the right of the _Auster_ +(south wind); then _Libonotus_; then _Africus_, which is the middle one +of these five; after that comes _Subvesperus_; next _Argestes_, to the +left of _Favonius_ (west wind). All these, with the exception of +_Libonotus_ and _Argestes_, have Latin names; but _Africus_ also is +called by the Greeks [Greek: Lips]. In a similar manner, between +_Favonius_ (west wind) and _Septentrio_ (north wind), first to the right +of _Favonius_ (west wind), is the _Etesiae_; then _Circius_; then +_Caurus_, which is in the middle of these five; then _Corus_; and lastly +_Thrascias_ to the left of _Septentrio_ (north wind). To all of these, +except that of _Caurus_, the Greeks gave the names, and those who do not +distinguish the winds by so exact a plan, assert that the wind which the +Greeks called [Greek: Koros] and the Latins _Caurus_ is one and the +same. Again, between _Septentrio_ (north wind) and the _Subsolanus_ +(east wind), the first to the right of _Septentrio_ (north wind) is +_Gallicus_; then _Supernas_; then _Aquilo_, which is the middle one of +these five; next comes _Boreas_; and lastly _Carbas_, to the left of +_Subsolanus_ (east wind). Here again, those who do not consider the +winds to be in so great a multitude, but say there are but twelve winds +in all, or at the most fourteen, assert that the wind called by the +Greeks [Greek: Boreas] and the Latins _Aquilo_ is one and the same. For +our purpose it is not only useful to adopt this large number of winds, +but even to double it, as the German sailors do. They always reckon that +between each two there is one in the centre taken from both. By this +method we also are able to signify the intermediate directions by means +of the names of the winds. For instance, if a vein runs from VI east to +VI west, it is said to proceed from _Subsolanus_ (east wind) to +_Favonius_ (west wind); but one which proceeds from between V and VI of +the east to between V and VI west is said to proceed out of the middle +of _Carbas_ and _Subsolanus_ to between _Argestes_ and _Favonius_; the +remaining directions, and their intermediates are similarly designated. +The miner, on account of the natural properties of a magnet, by which +the needle points to the south, must fix the instrument already +described so that east is to the left and west to the right. + +[Illustration 60 (Veins in mountain): A, B--_Venae dilatatae_. C--_Seams +in the Rocks_.] + +In a similar way to _venae profundae_, the _venae dilatatae_ vary in +their lateral directions, and we are able to understand from the seams +in the rocks in which direction they extend into the ground. For if +these incline toward the west in depth, the vein is said to extend from +east to west; if on the contrary, they incline toward the east, the vein +is said to go from west to east. In the same way, from the rock seams we +can determine veins running south and north, or the reverse, and +likewise to the subordinate directions and their intermediates. + +[Illustration 61a (Veins in mountain): A--Straight _vena profunda_. +B--Curved _vena profunda_ [should be _vena dilatata_(?)].] + +Further, as regards the question of direction of a _vena profunda_, one +runs straight from one quarter of the earth to that quarter which is +opposite, while another one runs in a curve, in which case it may happen +that a vein proceeding from the east does not turn to the quarter +opposite, which is the west, but twists itself and turns to the south or +the north. + +[Illustration 61b (Veins in mountain): A--Horizontal _vena dilatata_. +B--Inclined _vena dilatata_. C--Curved _vena dilatata_.] + +Similarly some _venae dilatatae_ are horizontal, some are inclined, and +some are curved. + +[Illustration 62a (Veins in mountain)] + +Also the veins which we call _profundae_ differ in the manner in which +they descend into the depths of the earth; for some are vertical (A), +some are inclined and sloping (B), others crooked (C). + +[Illustration 62b (Veins in mountain)] + +Moreover, _venae profundae_ (B) differ much among themselves regarding +the kind of locality through which they pass, for some extend along the +slopes of mountains or hills (A-C) and do not descend down the sides. + +[Illustration 63a (Veins in mountain)] + +Other _Venae Profundae_ (D, E, F) from the very summit of the mountain +or hill descend the slope (A) to the hollow or valley (B), and they +again ascend the slope or the side of the mountain or hill opposite (C). + +[Illustration 63b (Veins in mountain)] + +Other _Venae Profundae_ (C, D) descend the mountain or hill (A) and +extend out into the plain (B). + +[Illustration 64a (Veins in mountain): A--Mountainous Plain. B--_Vena +profunda_.] + +Some veins run straight along on the plateaux, the hills, or plains. + +[Illustration 64b (Intersections of Veins): A--Principal vein. +B--Transverse vein. C--Vein cutting principal one obliquely.] + +In the next place, _venae profundae_ differ not a little in the manner +in which they intersect, since one may cross through a second +transversely, or one may cross another one obliquely as if cutting it in +two. + +[Illustration 65 (Intersections of Veins): A--Principal vein. B--Vein +which cuts A obliquely. C--Part carried away. D--That part which has +been carried forward.] + +If a vein which cuts through another principal one obliquely be the +harder of the two, it penetrates right through it, just as a wedge of +beech or iron can be driven through soft wood by means of a tool. If it +be softer, the principal vein either drags the soft one with it for a +distance of three feet, or perhaps one, two, three, or several fathoms, +or else throws it forward along the principal vein; but this latter +happens very rarely. But that the vein which cuts the principal one is +the same vein on both sides, is shown by its having the same character +in its footwalls and hangingwalls. + +[Illustration 66a (Intersections of Veins): A, B--Two veins descend +inclined and dip toward each other. C--Junction. Likewise two veins. +D--Indicates one descending vertically. E--Marks the other descending +inclined, which dips toward D. F--Their junction.] + +Sometimes _venae profundae_ join one with another, and from two or more +outcropping veins[4], one is formed; or from two which do not outcrop +one is made, if they are not far distant from each other, and the one +dips into the other, or if each dips toward the other, and they thus +join when they have descended in depth. In exactly the same way, out of +three or more veins, one may be formed in depth. + +[Illustration 66b (Intersections of Veins)] + +However, such a junction of veins sometimes disunites and in this way +it happens that the vein which was the right-hand vein becomes the left; +and again, the one which was on the left becomes the right. + +Furthermore, one vein may be split and divided into parts by some hard +rock resembling a beak, or stringers in soft rock may sunder the vein +and make two or more. These sometimes join together again and sometimes +remain divided. + +[Illustration 67 (Intersections of Veins): A, B--Veins dividing. C--The +same joining.] + +Whether a vein is separating from or uniting with another can be +determined only from the seams in the rocks. For example, if a principal +vein runs from the east to the west, the rock seams descend in depth +likewise from the east toward the west, and the associated vein which +joins with the principal vein, whether it runs from the south or the +north, has its rock seams extending in the same way as its own, and they +do not conform with the seams in the rock of the principal vein--which +remain the same after the junction--unless the associated vein proceeds +in the same direction as the principal vein. In that case we name the +broader vein the principal one, and the narrower the associated vein. +But if the principal vein splits, the rock seams which belong +respectively to the parts, keep the same course when descending in depth +as those of the principal vein. + +[Illustration 68 (Intersections of Veins): A, C--_Vena dilatata_ +crossing a _vena profunda_. B--_Vena profunda_. D, E--_Vena dilatata_ +which junctions with a _vena profunda_. F--_Vena profunda_. G--_Vena +dilatata_. H, I--Its divided parts. K--_Vena profunda_ which divides the +_vena dilatata_.] + +But enough of _venae profundae_, their junctions and divisions. Now we +come to _venae dilatatae_. A _vena dilatata_ may either cross a _vena +profunda_, or join with it, or it may be cut by a _vena profunda_, and +be divided into parts. + +[Illustration 69a (Veins in mountain): A--The "beginning" (_origo_). +B--The "end" (_finis_). C--The "head" (_caput_). D--The "tail" +(_cauda_).] + +Finally, a _vena profunda_ has a "beginning" (_origo_), an "end" +(_finis_), a "head" (_caput_), and a "tail" (_cauda_). That part whence +it takes its rise is said to be its "beginning," that in which it +terminates the "end." Its "head"[5] is that part which emerges into +daylight; its "tail" that part which is hidden in the earth. But miners +have no need to seek the "beginning" of veins, as formerly the kings of +Egypt sought for the source of the Nile, but it is enough for them to +discover some other part of the vein and to recognise its direction, for +seldom can either the "beginning" or the "end" be found. The direction +in which the head of the vein comes into the light, or the direction +toward which the tail extends, is indicated by its footwall and +hangingwall. The latter is said to hang, and the former to lie. The vein +rests on the footwall, and the hangingwall overhangs it; thus, when we +descend a shaft, the part to which we turn the face is the footwall and +seat of the vein, that to which we turn the back is the hangingwall. +Also in another way, the head accords with the footwall and the tail +with the hangingwall, for if the footwall is toward the south, the vein +extends its head into the light toward the south; and the hangingwall, +because it is always opposite to the footwall, is then toward the north. +Consequently the vein extends its tail toward the north if it is an +inclined _vena profunda_. Similarly, we can determine with regard to +east and west and the subordinate and their intermediate directions. A +_vena profunda_ which descends into the earth may be either vertical, +inclined, or crooked; the footwall of an inclined vein is easily +distinguished from the hangingwall, but it is not so with a vertical +vein; and again, the footwall of a crooked vein is inverted and changed +into the hangingwall, and contrariwise the hangingwall is twisted into +the footwall, but very many of these crooked veins may be turned back to +vertical or inclined ones. + +[Illustration 69b (Veins in mountain): A--The "beginning." B--The "end." +C, D--The "sides."] + +A _vena dilatata_ has only a "beginning" and an "end," and in the place +of the "head" and "tail" it has two sides. + +[Illustration 70 (Veins in mountain): A--The "beginning." B--The "end." +C--The "head." D--The "tail." E--Transverse vein.] + +A _vena cumulata_ has a "beginning," an "end," a "head," and a "tail," +just as a _vena profunda_. Moreover, a _vena cumulata_, and likewise a +_vena dilatata_, are often cut through by a transverse _vena profunda_. + +[Illustration 71a (Fibra dilatata): A, B--Veins. C--Transverse +stringer. D--Oblique stringer. E--Associated stringer. F--_Fibra +dilatata_.] + +Stringers (_fibrae_)[6], which are little veins, are classified into +_fibrae transversae_, _fibrae obliquae_ which cut the vein obliquely, +_fibrae sociae_, _fibrae dilatatae_, and _fibrae incumbentes_. The +_fibra transversa_ crosses the vein; the _fibra obliqua_ crosses the +vein obliquely; the _fibra socia_ joins with the vein itself; the _fibra +dilatata_, like the _vena dilatata_, penetrates through it; but the +_fibra dilatata_, as well as the _fibra profunda_, is usually found +associated with a vein. + +[Illustration 71b (Fibra incumbens): A--Vein. B--_Fibra incumbens_ from +the surface of the hangingwall. C--Same from the footwall.] + +The _fibra incumbens_ does not descend as deeply into the earth as the +other stringers, but lies on the vein, as it were, from the surface to +the hangingwall or footwall, from which it is named _Subdialis_.[7] + +In truth, as to direction, junctions, and divisions, the stringers are +not different from the veins. + +[Illustration 72 (Seams in the Rocks): A--Seams which proceed from the +east. B--The inverse.] + +Lastly, the seams, which are the very finest stringers (_fibrae_), +divide the rock, and occur sometimes frequently, sometimes rarely. From +whatever direction the vein comes, its seams always turn their heads +toward the light in the same direction. But, while the seams usually run +from one point of the compass to another immediately opposite it, as for +instance, from east to west, if hard stringers divert them, it may +happen that these very seams, which before were running from east to +west, then contrariwise proceed from west to east, and the direction of +the rocks is thus inverted. In such a case, the direction of the veins +is judged, not by the direction of the seams which occur rarely, but by +those which constantly recur. + +[Illustration 73 (Veins in mountain): A--Solid vein. B--Solid stringer. +C--Cavernous vein. D--Cavernous stringer. E--Barren vein. F--Barren +stringer.] + +Both veins or stringers may be solid or drusy, or barren of minerals, or +pervious to water. Solid veins contain no water and very little air. The +drusy veins rarely contain water; they often contain air. Those which +are barren of minerals often carry water. Solid veins and stringers +consist sometimes of hard materials, sometimes of soft, and sometimes of +a kind of medium between the two. + +But to return to veins. A great number of miners consider[8] that the +best veins in depth are those which run from the VI or VII direction of +the east to the VI or VII direction of the west, through a mountain +slope which inclines to the north; and whose hangingwalls are in the +south, and whose footwalls are in the north, and which have their heads +rising to the north, as explained before, always like the footwall, and +finally, whose rock seams turn their heads to the east. And the veins +which are the next best are those which, on the contrary, extend from +the VI or VII direction of the west to the VI or VII direction of the +east, through the slope of a mountain which similarly inclines to the +north, whose hangingwalls are also in the south, whose footwalls are in +the north, and whose heads rise toward the north; and lastly, whose rock +seams raise their heads toward the west. In the third place, they +recommend those veins which extend from XII north to XII south, through +the slope of a mountain which faces east; whose hangingwalls are in the +west, whose footwalls are in the east; whose heads rise toward the east; +and whose rock seams raise their heads toward the north. Therefore they +devote all their energies to those veins, and give very little or +nothing to those whose heads, or the heads of whose rock seams rise +toward the south or west. For although they say these veins sometimes +show bright specks of pure metal adhering to the stones, or they come +upon lumps of metal, yet these are so few and far between that despite +them it is not worth the trouble to excavate such veins; and miners who +persevere in digging in the hope of coming upon a quantity of metal, +always lose their time and trouble. And they say that from veins of this +kind, since the sun's rays draw out the metallic material, very little +metal is gained. But in this matter the actual experience of the miners +who thus judge of the veins does not always agree with their opinions, +nor is their reasoning sound; since indeed the veins which run from east +to west through the slope of a mountain which inclines to the south, +whose heads rise likewise to the south, are not less charged with +metals, than those to which miners are wont to accord the first place in +productiveness; as in recent years has been proved by the St. Lorentz +vein at Abertham, which our countrymen call Gottsgaab, for they have dug +out of it a large quantity of pure silver; and lately a vein in +Annaberg, called by the name of Himmelsch hoz[9], has made it plain by +the production of much silver that veins which extend from the north to +the south, with their heads rising toward the west, are no less rich in +metals than those whose heads rise toward the east. + +It may be denied that the heat of the sun draws the metallic material +out of these veins; for though it draws up vapours from the surface of +the ground, the rays of the sun do not penetrate right down to the +depths; because the air of a tunnel which is covered and enveloped by +solid earth to the depth of only two fathoms is cold in summer, for the +intermediate earth holds in check the force of the sun. Having observed +this fact, the inhabitants and dwellers of very hot regions lie down by +day in caves which protect them from the excessive ardour of the sun. +Therefore it is unlikely that the sun draws out from within the earth +the metallic bodies. Indeed, it cannot even dry the moisture of many +places abounding in veins, because they are protected and shaded by the +trees. Furthermore, certain miners, out of all the different kinds of +metallic veins, choose those which I have described, and others, on the +contrary, reject copper mines which are of this sort, so that there +seems to be no reason in this. For what can be the reason if the sun +draws no copper from copper veins, that it draws silver from silver +veins, and gold from gold veins? + +Moreover, some miners, of whose number was Calbus[10], distinguish +between the gold-bearing rivers and streams. A river, they say, or a +stream, is most productive of fine and coarse grains of gold when it +comes from the east and flows to the west, and when it washes against +the foot of mountains which are situated in the north, and when it has a +level plain toward the south or west. In the second place, they esteem a +river or a stream which flows in the opposite course from the west +toward the east, and which has the mountains to the north and the level +plain to the south. In the third place, they esteem the river or the +stream which flows from the north to the south and washes the base of +the mountains which are situated in the east. But they say that the +river or stream is least productive of gold which flows in a contrary +direction from the south to the north, and washes the base of mountains +which are situated in the west. Lastly, of the streams or rivers which +flow from the rising sun toward the setting sun, or which flow from the +northern parts to the southern parts, they favour those which approach +the nearest to the lauded ones, and say they are more productive of +gold, and the further they depart from them the less productive they +are. Such are the opinions held about rivers and streams. Now, since +gold is not generated in the rivers and streams, as we have maintained +against Albertus[11] in the book entitled "_De Subterraneorum Ortu et +Causis_," Book V, but is torn away from the veins and stringers and +settled in the sands of torrents and water-courses, in whatever +direction the rivers or streams flow, therefore it is reasonable to +expect to find gold therein; which is not opposed by experience. +Nevertheless, we do not deny that gold is generated in veins and +stringers which lie under the beds of rivers or streams, as in other +places. + + END OF BOOK III. + + +FOOTNOTES: + +[1] Modern nomenclature in the description of ore-deposits is so +impregnated with modern views of their origin, that we have considered +it desirable in many instances to adopt the Latin terms used by the +author, for we believe this method will allow the reader greater freedom +of judgment as to the author's views. The Latin names retained are +usually expressive even to the non-Latin student. In a general way, a +_vena profunda_ is a fissure vein, a _vena dilatata_ is a bedded +deposit, and a _vena cumulata_ an impregnation, or a replacement or a +_stockwerk_. The _canales_, as will appear from the following footnote, +were ore channels. "The seams of the rocks" (_commissurae saxorum_) are +very puzzling. The author states, as appears in the following note, that +they are of two kinds,--contemporaneous with the formation of the rocks, +and also of the nature of veinlets. However, as to their supposed +relation to the strike of veins, we can offer no explanation. There are +passages in this chapter where if the word "ore-shoot" were introduced +for "seams in the rocks" the text would be intelligible. That is, it is +possible to conceive the view that the determination of whether an +east-west vein ran east or ran west was dependent on the dip of the +ore-shoot along the strike. This view, however, is utterly impossible to +reconcile with the description and illustration of _commissurae saxorum_ +given on page 54, where they are defined as the finest stringers. The +following passage from the _Nützliche Bergbüchlin_ (see Appendix), reads +very much as though the dip of ore-shoots was understood at this time in +relation to the direction of veins. "Every vein (_gang_) has two +(outcrops) _ausgehen_, one of the _ausgehen_ is toward daylight along +the whole length of the vein, which is called the _ausgehen_ of the +whole vein. The other _ausgehen_ is contrary to or toward the strike +(_streichen_) of the vein, according to its rock (_gestein_), that is +called the _gesteins ausgehen_; for instance, every vein that has its +strike from east to west has its _gesteins ausgehen_ to the east, and +_vice-versa_." + +Agricola's classification of ore-deposits, after the general distinction +between alluvial and _in situ_ deposits, is based entirely upon form, as +will be seen in the quotation below relating to the origin of _canales_. +The German equivalents in the Glossary are as follows:-- + + Fissure vein (_vena profunda_) _Gang._ + Bedded deposit (_vena dilatata_) _Schwebender gang oder fletze._ + Stockwerk or impregnation (_vena cumulata_) _Geschute oder stock._ + Stringer (_fibra_) _Klufft._ + Seams or joints (_commissurae saxorum_) _Absetzen des gesteins._ + +It is interesting to note that in _De Natura Fossilium_ he describes +coal and salt, and later in _De Re Metallica_ he describes the Mannsfeld +copper schists, as all being _venae dilatatae_. This nomenclature and +classification is not original with Agricola. Pliny (XXXIII, 21) uses +the term _vena_ with no explanations, and while Agricola coined the +Latin terms for various kinds of veins, they are his transliteration of +German terms already in use. The _Nützliche Bergbüchlin_ gives this same +classification. + +HISTORICAL NOTE ON THE THEORY OF ORE DEPOSITS. Prior to Agricola there +were three schools of explanation of the phenomena of ore deposits, the +orthodox followers of the Genesis, the Greek Philosophers, and the +Alchemists. The geology of the Genesis--the contemporaneous formation of +everything--needs no comment other than that for anyone to have proposed +an alternative to the dogma of the orthodox during the Middle Ages, +required much independence of mind. Of the Greek views--which are meagre +enough--that of the Peripatetics greatly dominated thought on natural +phenomena down to the 17th century. Aristotle's views may be summarized: +The elements are earth, water, air, and fire; they are transmutable and +never found pure, and are endowed with certain fundamental properties +which acted as an "efficient" force upon the material cause--the +elements. These properties were dryness and dampness and heat and cold, +the latter being active, the former passive. Further, the elements were +possessed of weight and lightness, for instance earth was absolutely +heavy, fire absolutely light. The active and passive properties existed +in binary combinations, one of which is characteristic, _i.e._, "earth" +is cold and dry, water damp and cold, fire hot and dry, air hot and wet; +transmutation took place, for instance, by removing the cold from water, +when air resulted (really steam), and by removing the dampness from +water, when "earth" resulted (really any dissolved substance). The +transmutation of the elements in the earth (meaning the globe) produces +two "exhalations," the one fiery (probably meaning gases), the other +damp (probably meaning steam). The former produces stones, the latter +the metals. Theophrastus (On Stones, I to VII.) elaborates the views of +Aristotle on the origin of stones, metals, etc.: "Of things formed in +the earth some have their origin from water, others from earth. Water is +the basis of metals, silver, gold, and the rest; 'earth' of stones, as +well the more precious as the common.... All these are formed by +solidification of matter pure and equal in its constituent parts, which +has been brought together in that state by mere afflux or by means of +some kind of percolation, or separated.... The solidification is in some +of these substances due to heat and in others to cold." (Based on Hill's +Trans., pp. 3-11). That is, the metals inasmuch as they become liquid +when heated must be in a large part water, and, like water, they +solidify with cold. Therefore, the "metals are cold and damp." Stones, +on the other hand, solidify with heat and do not liquefy, therefore, +they are "dry and hot" and partake largely of "earth." This "earth" was +something indefinite, but purer and more pristine than common clay. In +discussing the ancient beliefs with regard to the origin of deposits, we +must not overlook the import of the use of the word "vein" (_vena_) by +various ancient authors including Pliny (XXXIII, 21), although he offers +no explanation of the term. + +During the Middle Ages there arose the horde of Alchemists and +Astrologers, a review of the development of whose muddled views is but +barren reading. In the main they held more or less to the Peripatetic +view, with additions of their own. Geber (13th (?) century, see Appendix +B) propounded the conception that all metals were composed of varying +proportions of "spiritual" sulphur and quicksilver, and to these +Albertus Magnus added salt. The Astrologers contributed the idea that +the immediate cause of the metals were the various planets. The only +work devoted to description of ore-deposits prior to Agricola was the +_Bergbüchlin_ (about 1520, see Appendix B), and this little book +exhibits the absolute apogee of muddled thought derived from the +Peripatetics, the Alchemists, and the Astrologers. We believe it is of +interest to reproduce the following statement, if for no other reason +than to indicate the great advance in thought shown by Agricola. + +"The first chapter or first part; on the common origin of ore, whether +silver, gold, tin, copper, iron, or lead ore, in which they all appear +together, and are called by the common name of metallic ore. It must be +noticed that for the washing or smelting of metallic ore, there must be +the one who works and the thing that is worked upon, or the material +upon which the work is expended. The general worker (efficient force) on +the ore and on all things that are born, is the heavens, its movement, +its light and influences, as the philosophers say. The influence of the +heavens is multiplied by the movement of the firmaments and the +movements of the seven planets. Therefore, every metallic ore receives a +special influence from its own particular planet, due to the properties +of the planet and of the ore, also due to properties of heat, cold, +dampness, and dryness. Thus gold is of the Sun or its influence, silver +of the Moon, tin of Jupiter, copper of Venus, iron of Mars, lead of +Saturn, and quicksilver of Mercury. Therefore, metals are often called +by these names by hermits and other philosophers. Thus gold is called +the Sun, in Latin _Sol_, silver is called the Moon, in Latin _Luna_, as +is clearly stated in the special chapters on each metal. Thus briefly +have we spoken of the 'common worker' of metal and ore. But the thing +worked upon, or the common material of all metals, according to the +opinion of the learned, is sulphur and quicksilver, which through the +movement and influence of the heavens must have become united and +hardened into one metallic body or one ore. Certain others hold that +through the movement and the influence of the heavens, vapours or +_braden_, called mineral exhalations, are drawn up from the depths of +the earth, from sulphur and quicksilver, and the rising fumes pass into +the veins and stringers and are united through the effect of the planets +and made into ore. Certain others hold that metal is not formed from +quicksilver, because in many places metallic ore is found and no +quicksilver. But instead of quicksilver they maintain a damp and cold +and slimy material is set up on all sulphur which is drawn out from the +earth, like your perspiration, and from that mixed with sulphur all +metals are formed. Now each of these opinions is correct according to a +good understanding and right interpretation; the ore or metal is formed +from the fattiness of the earth as the material of the first degree +(primary element), also the vapours or _braden_ on the one part and the +materials on the other part, both of which are called quicksilver. +Likewise in the mingling or union of the quicksilver and the sulphur in +the ore, the sulphur is counted the male and quicksilver the female, as +in the bearing or conception of a child. Also the sulphur is a special +worker in ore or metal. + +"The second chapter or part deals with the general capacity of the +mountain. Although the influence of the heavens and the fitness of the +material are necessary to the formation of ore or metal, yet these are +not enough thereto. But there must be adaptability of the natural vessel +in which the ore is formed, such are the veins, namely _steinendegange_, +_flachgange_, _schargange_, _creutzgange_, or as these may be termed in +provincial names. Also the mineral force must have easy access to the +natural vessel such as through the _kluffte_ (stringers), namely +_hengkluft_, _querklufte_, _flachekluffte_, _creutzklufft_, and other +occasional _flotzwerk_, according to their various local names. Also +there must be a suitable place in the mountain which the veins and +stringers can traverse." + +AGRICOLA'S VIEWS ON THE ORIGIN OF ORE DEPOSITS. Agricola rejected +absolutely the Biblical view which, he says, was the opinion of the +vulgar; further, he repudiates the alchemistic and astrological view +with great vigour. There can be no doubt, however, that he was greatly +influenced by the Peripatetic philosophy. He accepted absolutely the +four elements--earth, fire, water, and air, and their "binary" +properties, and the theory that every substance had a material cause +operated upon by an efficient force. Beyond this he did not go, and a +large portion of _De Ortu et Causis_ is devoted to disproof of the +origin of metals and stones from the Peripatetic "exhalations." + +No one should conclude that Agricola's theories are set out with the +clarity of Darwin or Lyell. However, the matter is of such importance in +the history of the theory of ore-deposits, and has been either so +ignored or so coloured by the preconceptions of narrators, that we +consider it justifiable to devote the space necessary to a reproduction +of his own statements in _De Ortu et Causis_ and other works. Before +doing so we believe it will be of service to readers to summarize these +views, and in giving quotations from the Author's other works, to group +them under special headings, following the outline of his theory given +below. His theory was:-- + +(1) Openings in the earth (_canales_) were formed by the erosion of +subterranean waters. + +(2) These ground waters were due (_a_) to the infiltration of the +surface waters, rain, river, and sea water; (_b_) to the condensation of +steam (_halitus_) arising from the penetration of the surface waters to +greater depths,--the production of this _halitus_ being due to +subterranean heat, which in his view was in turn due in the main to +burning bitumen (a comprehensive genera which embraced coal). + +(3) The filling of these _canales_ is composed of "earth," "solidified +juices," "stone," metals, and "compounds," all deposited from water and +"juices" circulating in the _canales_. (See also note 4, page 1). + +"Earth" comprises clay, mud, ochre, marl, and "peculiar earths" +generally. The origin of these "earths" was from rocks, due to erosion, +transportation, and deposition by water. "Solidified juices" (_succi +concreti_) comprised salt, soda, vitriol, bitumen, etc., being generally +those substances which he conceived were soluble in and deposited from +water. "Stones" comprised precious, semi-precious, and unusual stones, +such as quartz, fluor-spar, etc., as distinguished from country rock; +the origin of these he attributed in minor proportion to transportation +of fragments of rock, but in the main to deposits from ordinary mineral +juice and from "stone juice" (_succus lapidescens_). Metals comprised +the seven traditional metals; the "compounds" comprised the metallic +minerals; and both were due to deposition from juices, the compounds +being due to a mixture of juices. The "juices" play the most important +part in Agricola's theory. Each substance had its own particular juice, +and in his theory every substance had a material and an efficient cause, +the first being the juice, the second being heat or cold. Owing to the +latter the juices fell into two categories--those solidified by heat +(_i.e._, by evaporation, such as salt), and those solidified by cold, +(_i.e._, because metals melt and flow by heat, therefore their +solidification was due to cold, and the juice underwent similar +treatment). As to the origin of these juices, some were generated by the +solution of their own particular substance, but in the main their origin +was due to the combination of "dry things," such as "earth," with water, +the mixture being heated, and the resultant metals depended upon the +proportions of "earth" and water. In some cases we have been inclined to +translate _succus_ (juice) as "solution," but in other cases it embraced +substances to which this would not apply, and we feared implying in the +text a chemical understanding not warranted prior to the atomic theory. +In order to distinguish between earths, (clays, etc.,) the Peripatetic +"earth" (a pure element) and the earth (the globe) we have given the two +former in quotation marks. There is no doubt some confusion between +earth (clays, etc.) and the Peripatetic "earth," as the latter was a +pure substance not found in its pristine form in nature; it is, however, +difficult to distinguish between the two. + +ORIGIN OF CANALES (_De Ortu_, p. 35). "I now come to the _canales_ in +the earth. These are veins, veinlets, and what are called 'seams in the +rocks.' These serve as vessels or receptacles for the material from +which minerals (_res fossiles_) are formed. The term _vena_ is most +frequently given to what is contained in the _canales_, but likewise the +same name is applied to the _canales_ themselves. The term vein is +borrowed from that used for animals, for just as their veins are +distributed through all parts of the body, and just as by means of the +veins blood is diffused from the liver throughout the whole body, so +also the veins traverse the whole globe, and more particularly the +mountainous districts; and water runs and flows through them. With +regard to veinlets or stringers and 'seams in the rocks,' which are the +thinnest stringers, the following is the mode of their arrangement. +Veins in the earth, just like the veins of an animal, have certain +veinlets of their own, but in a contrary way. For the larger veins of +animals pour blood into the veinlets, while in the earth the humours are +usually poured from the veinlets into the larger veins, and rarely flow +from the larger into the smaller ones. As for the seams in the rocks +(_commissurae saxorum_) we consider that they are produced by two +methods: by the first, which is peculiar to themselves, they are formed +at the same time as the rocks, for the heat bakes the refractory +material into stone and the non-refractory material similarly heated +exhales its humours and is made into 'earth,' generally friable. The +other method is common also to veins and veinlets, when water is +collected into one place it softens the rock by its liquid nature, and +by its weight and pressure breaks and divides it. Now, if the rock is +hard, it makes seams in the rocks and veinlets, and if it is not too +hard it makes veins. However, if the rocks are not hard, seams and +veinlets are created as well as veins. If these do not carry a very +large quantity of water, or if they are pressed by a great volume of it, +they soon discharge themselves into the nearest veins. The following +appears to be the reason why some veinlets or stringers and veins are +_profundae_ and others _dilatatae_. The force of the water crushes and +splits the brittle rocks; and when they are broken and split, it forces +its way through them and passes on, at one time in a downward direction, +making small and large _venae profundae_, at another time in a lateral +direction, in which way _venae dilatatae_ are formed. Now since in each +class there are found some which are straight, some inclined, and some +crooked, it should be explained that the water makes the _vena profunda_ +straight when it runs straight downward, inclined when it runs in an +inclined direction; and that it makes a _vena dilatata_ straight when it +runs horizontally to the right or left, and in a similar way inclined +when it runs in a sloping direction. Stringers and large veins of the +_profunda_ sort, extending for considerable lengths, become crooked from +two causes. In one case when narrow veins are intersected by wide ones, +then the latter bend or drag the former a little. In the other case, +when the water runs against very hard rock, being unable to break +through, it goes around the nearest way, and the stringers and veins are +formed bent and crooked. This last is also the reason we sometimes see +crooked small and large _venae dilatatae_, not unlike the gentle rise +and fall of flowing water. Next, _venae profundae_ are wide, either +because of abundant water or because the rock is fragile. On the other +hand, they are narrow, either because but little water flows and +trickles through them, or because the rock is very hard. The _venae +dilatatae_, too, for the same reasons, are either thin or thick. There +are other differences, too, in stringers and veins, which I will explain +in my work _De Re Metallica_.... There is also a third kind of vein +which, as it cannot be described as a wide _vena profunda_, nor as a +thick _vena dilatata_, we will call a _vena cumulata_. These are nothing +else than places where some species of mineral is accumulated; sometimes +exceeding in depth and also in length and breadth 600 feet; sometimes, +or rather generally, not so deep nor so long, nor so wide. These are +created when water has broken away the rock for such a length, breadth, +and thickness, and has flung aside and ejected the stones and sand from +the great cavern which is thus made; and afterward when the mouth is +obstructed and closed up, the whole cavern is filled with material from +which there is in time produced some one or more minerals. Now I have +stated when discoursing on the origin of subterranean humours, that +water erodes away substances inside the earth, just as it does those on +the surface, and least of all does it shun minerals; for which reason we +may daily see veinlets and veins sometimes filled with air and water, +but void and empty of mining products, and sometimes full of these same +materials. Even those which are empty of minerals become finally +obstructed, and when the rock is broken through at some other point the +water gushes out. It is certain that old springs are closed up in some +way and new ones opened in others. In the same manner, but much more +easily and quickly than in the solid rock, water produces stringers and +veins in surface material, whether it be in plains, hills, or mountains. +Of this kind are the stringers in the banks of rivers which produce +gold, and the veins which produce peculiar earth. So in this manner in +the earth are made _canales_ which bear minerals." + +ORIGIN OF GROUND WATERS. (_De Ortu_ p. 5). "... Besides rain there is +another kind of water by which the interior of the earth is soaked, so +that being heated it can continually give off _halitus_, from which +arises a great and abundant force of waters." In description of the +_modus operandi_ of _halitum_, he says (p. 6): "... _Halitus_ rises to +the upper parts of the _canales_, where the congealing cold turns it +into water, which by its gravity and weight again runs down to the +lowest parts and increases the flow of water if there is any. If any +finds its way through a _canales dilatata_ the same thing happens, but +it is carried a long way from its place of origin. The first phase of +distillation teaches us how this water is produced, for when that which +is put into the ampulla is warmed it evaporates (_expirare_), and this +_halitus_ rising into the operculum is converted by cold into water, +which drips through the spout. In this way water is being continually +created underground." (_De Ortu_, p. 7): "And so we know from all this +that of the waters which are under the earth, some are collected from +rain, some arise from _halitus_ (steam), some from river-water, some +from sea-water; and we know that the _halitum_ is produced within the +earth partly from rain-water, partly from river-water, and partly from +sea-water." It would require too much space to set out Agricola's views +upon the origin of the subterranean heat which produced this steam. It +is an involved theory embracing clashing winds, burning bitumen, coal, +etc., and is fully set out in the latter part of Book II, _De Ortu et +Causis_. + +ORIGIN OF GANGUE MINERALS. It is necessary to bear in mind that Agricola +divided minerals (_res fossiles_--"Things dug up," see note 4, p. 1) +into "earths," "solidified juices," "stones," "metals," and "compounds;" +and, further, to bear in mind that in his conception of the origin of +things generally, he was a disciple of the Peripatetic logic of a +"material substance" and an "efficient force," as mentioned above. + +As to the origin of "earths," he says (_De Ortu_, p. 38): "Pure and +simple 'earth' originates in the _canales_ in the following way: rain +water, which is absorbed by the surface of the earth, first of all +penetrates and passes into the inner parts of the earth and mixes with +it; next, it is collected from all sides into stringers and veins, where +it, and sometimes water of other origin, erodes the 'earth' away,--a +great quantity of it if the stringers and veins are in 'earth,' a small +quantity if they are in rock. The softer the rock is, the more the water +wears away particles by its continual movement. To this class of rock +belongs limestone, from which we see chalk, clay, and marl, and other +unctuous 'earths' made; also sandstone, from which are made those barren +'earths' which we may see in ravines and on bare rocks. For the rain +softens limestone or sandstone and carries particles away with it, and +the sediment collects together and forms mud, which afterward solidifies +into some kind of 'earth.' In a similar way under the ground the power +of water softens the rock and dissolves the coarser fragments of stone. +This is clearly shown by the following circumstance, that frequently the +powder of rock or marble is found in a soft state and as if partly +dissolved. Now, the water carries this mixture into the course of some +underground _canalis_, or dragging it into narrow places, filters away. +And in each case the water flows away and a pure and uniform material is +left from which 'earth' is made.... Particles of rock, however, are only +by force of long time so softened by water as to become similar to +particles of 'earth.' It is possible to see 'earth' being made in this +way in underground _canales_ in the earth, when drifts or tunnels are +driven into the mountains, or when shafts are sunk, for then the +_canales_ are laid bare; also it can be seen above ground in ravines, as +I have said, or otherwise disclosed. For in both cases it is clear to +the eye that they are made out of the 'earth' or rocks, which are often +of the same colour. And in just the same way they are made in the +springs which the veins discharge. Since all those things which we see +with our eyes and which are perceived with our senses, are more clearly +understood than if they were learnt by means of reasoning, we deem it +sufficient to explain by this argument our view of the origin of +'earth.' In the manner which I have described, 'earths' originate in +veins and veinlets, seams in the rocks, springs, ravines, and other +openings, therefore all 'earths' are made in this way. As to those that +are found in underground _canales_ which do not appear to have been +derived from the earth or rock adjoining, these have undoubtedly been +carried by the water for a greater distance from their place of origin; +which may be made clear to anyone who seeks their source." + +On the origin of solidified juices he states (_De Ortu_, p. 43): "I will +now speak of solidified juices (_succi concreti_). I give this name to +those minerals which are without difficulty resolved into liquids +(_humore_). Some stones and metals, even though they are themselves +composed of juices, have been compressed so solidly by the cold that +they can only be dissolved with difficulty or not at all.... For juices, +as I said above, are either made when dry substances immersed in +moisture are cooked by heat, or else they are made when water flows over +'earth,' or when the surrounding moisture corrodes metallic material; or +else they are forced out of the ground by the power of heat alone. +Therefore, solidified juices originate from liquid juices, which either +heat or cold have condensed. But that which heat has dried, fire reduces +to dust, and moisture dissolves. Not only does warm or cold water +dissolve certain solidified juices, but also humid air; and a juice +which the cold has condensed is liquefied by fire and warm water. A +salty juice is condensed into salt; a bitter one into soda; an +astringent and sharp one into alum or into vitriol. Skilled workmen in a +similar way to nature, evaporate water which contains juices of this +kind until it is condensed; from salty ones they make salt, from +aluminous ones alum, from one which contains vitriol they make vitriol. +These workmen imitate nature in condensing liquid juices with heat, but +they cannot imitate nature in condensing them by cold. From an +astringent juice not only is alum made and vitriol, but also _sory_, +_chalcitis_, and _misy_, which appears to be the 'flower' of vitriol, +just as _melanteria_ is of _sory_. (See note on p. 573 for these +minerals.) When humour corrodes pyrites so that it is friable, an +astringent juice of this kind is obtained." + +ON THE ORIGIN OF STONES (_De Ortu_, p. 50), he states: "It is now +necessary to review in a few words what I have said as to all of the +material from which stones are made; there is first of all mud; next +juice which is solidified by severe cold; then fragments of rock; +afterward stone juice (_succus lapidescens_), which also turns to stone +when it comes out into the air; and lastly, everything which has pores +capable of receiving a stony juice." As to an "efficient force," he +states (p. 54): "But it is now necessary that I should explain my own +view, omitting the first and antecedent causes. Thus the immediate +causes are heat and cold; next in some way a stony juice. For we know +that stones which water has dissolved, are solidified when dried by +heat; and on the contrary, we know that stones which melt by fire, such +as quartz, solidify by cold. For solidification and the conditions which +are opposite thereto, namely, dissolving and liquefying, spring from +causes which are the opposite to each other. Heat, driving the water +(_humorem_) out of a substance, makes it hard; and cold, by withdrawing +the air, solidifies the same stone firmly. But if a stony juice, either +alone or mixed with water, finds its way into the pores either of plants +or animals ... it creates stones.... If stony juice is obtained in +certain stony places and flows through the veins, for this reason +certain springs, brooks, streams, and lakes, have the power of turning +things to stone." + +ON THE ORIGIN OF METALS, he says (_De Ortu_, p. 71): "Having now refuted +the opinions of others, I must explain what it really is from which +metals are produced. The best proof that there is water in their +materials is the fact that they flow when melted, whereas they are again +solidified by the cold of air or water. This, however, must be +understood in the sense that there is more water in them and less +'earth'; for it is not simply water that is their substance but water +mixed with 'earth.' And such a proportion of 'earth' is in the mixture +as may obscure the transparency of the water, but not remove the +brilliance which is frequently in unpolished things. Again, the purer +the mixture, the more precious the metal which is made from it, and the +greater its resistance to fire. But what proportion of 'earth' is in +each liquid from which a metal is made no mortal can ever ascertain, or +still less explain, but the one God has known it, Who has given certain +sure and fixed laws to nature for mixing and blending things together. +It is a juice (_succus_) then, from which metals are formed; and this +juice is created by various operations. Of these operations the first is +a flow of water which softens the 'earth' or carries the 'earth' along +with it, thus there is a mixture of 'earth' and water, then the power of +heat works upon the mixtures so as to produce that kind of a juice. We +have spoken of the substance of metals; we must now speak of their +efficient cause.... (p. 75): We do not deny the statement of Albertus +Magnus that the mixture of 'earth' and water is baked by subterranean +heat to a certain denseness, but it is our opinion that the juice so +obtained is afterward solidified by cold so as to become a metal.... We +grant, indeed, that heat is the efficient cause of a good mixture of +elements, and also cooks this same mixture into a juice, but until this +juice is solidified by cold it is not a metal.... (p. 76): This view of +Aristotle is the true one. For metals melt through the heat and somehow +become softened; but those which have become softened through heat are +again solidified by the influence of cold, and, on the contrary, those +which become softened by moisture are solidified by heat." + +ON THE ORIGIN OF COMPOUNDS, he states (_De Ortu_, p. 80): "There now +remain for our consideration the compound minerals (_mistae_), that is +to say, minerals which contain either solidified juice (_succus +concretus_) and 'stone,' or else metal or metals and 'stone,' or else +metal-coloured 'earth,' of which two or more have so grown together by +the action of cold that one body has been created. By this sign they are +distinguished from mixed minerals (_composita_), for the latter have not +one body. For example, pyrites, galena, and ruby silver are reckoned in +the category of compound minerals, whereas we say that metallic 'earths' +or stony 'earths' or 'earths' mingled with juices, are mixed minerals; +or similarly, stones in which metal or solidified juices adhere, or +which contain 'earth.' But of both these classes I will treat more fully +in my book _De Natura Fossilium_. I will now discuss their origin in a +few words. A compound mineral is produced when either a juice from which +some metal is obtained, or a _humour_ and some other juice from which +stone is obtained, are solidified by cold, or when two or more juices of +different metals mixed with the juice from which stone is made, are +condensed by the same cold, or when a metallic juice is mixed with +'earth' whose whole mass is stained with its colour, and in this way +they form one body. To the first class belongs _galena_, composed of +lead juice and of that material which forms the substance of opaque +stone. Similarly, transparent ruby silver is made out of silver juice +and the juice which forms the substance of transparent stone; when it is +smelted into pure silver, since from it is separated the transparent +juice, it is no longer transparent. Then too, there is pyrites, or +_lapis fissilis_, from which sulphur is melted. To the second kind +belongs that kind of pyrites which contains not only copper and stone, +but sometimes copper, silver, and stone; sometimes copper, silver, gold, +and stone; sometimes silver, lead, tin, copper and silver glance. That +compound minerals consist of stone and metal is sufficiently proved by +their hardness; that some are made of 'earth' and metal is proved from +brass, which is composed of copper and calamine; and also proved from +white brass, which is coloured by artificial white arsenic. Sometimes +the heat bakes some of them to such an extent that they appear to have +flowed out of blazing furnaces, which we may see in the case of _cadmia_ +and pyrites. A metallic substance is produced out of 'earth' when a +metallic juice impregnating the 'earth' solidifies with cold, the +'earth' not being changed. A stony substance is produced when viscous +and non-viscous 'earth' are accumulated in one place and baked by heat; +for then the viscous part turns into stone and the non-viscous is only +dried up." + +THE ORIGIN OF JUICES. The portion of Agricola's theory surrounding this +subject is by no means easy to follow in detail, especially as it is +difficult to adjust one's point of view to the Peripatetic elements, +fire, water, earth, and air, instead of to those of the atomic theory +which so dominates our every modern conception. That Agricola's 'juice' +was in most cases a solution is indicated by the statement (_De Ortu_, +p. 48): "Nor is juice anything but water, which on the other hand has +absorbed 'earth' or has corroded or touched metal and somehow become +heated." That he realized the difference between mechanical suspension +and solution is evident from (_De Ortu_, p. 50): "A stony juice differs +from water which has abraded something from rock, either because it has +more of that which deposits, or because heat, by cooking water of that +kind, has thickened it, or because there is something in it which has +powerful astringent properties." Much of the author's notion of juices +has already been given in the quotations regarding various minerals, but +his most general statement on the subject is as follows:--(_De Ortu_, p. +9): "Juices, however, are distinguished from water by their density +(_crassitudo_), and are generated in various ways--either when dry +things are soaked with moisture and the mixture is heated, in which way +by far the greatest part of juices arise, not only inside the earth, but +outside it; or when water running over the earth is made rather dense, +in which way, for the most part the juice becomes salty and bitter; or +when the moisture stands upon metal, especially copper, and corrodes it, +and in this way is produced the juice from which chrysocolla originates. +Similarly, when the moisture corrodes friable cupriferous pyrites an +acrid juice is made from which is produced vitriol and sometimes alum; +or, finally, juices are pressed out by the very force of the heat from +the earth. If the force is great the juice flows like pitch from burning +pine ... in this way we know a kind of bitumen is made in the earth. In +the same way different kinds of moisture are generated in living bodies, +so also the earth produces waters differing in quality, and in the same +way juices." + +CONCLUSION. If we strip his theory of the necessary influence of the +state of knowledge of his time, and of his own deep classical learning, +we find two propositions original with Agricola, which still to-day are +fundamentals: + +(1) That ore channels were of origin subsequent to their containing +rocks; (2) That ores were deposited from solutions circulating in these +openings. A scientist's work must be judged by the advancement he gave +to his science, and with this gauge one can say unhesitatingly that the +theory which we have set out above represents a much greater step from +what had gone before than that of almost any single observer since. +Moreover, apart from any tangible proposition laid down, the deduction +of these views from actual observation instead of from fruitless +speculation was a contribution to the very foundation of natural +science. Agricola was wrong in attributing the creation of ore channels +to erosion alone, and it was not until Von Oppel (_Anleitung zur +Markscheidekunst_, Dresden, 1749 and other essays), two centuries after +Agricola, that the positive proposition that ore channels were due to +fissuring was brought forward. Von Oppel, however, in neglecting +channels due to erosion (and in this term we include solution) was not +altogether sound. Nor was it until late in the 18th century that the +filling of ore channels by deposition from solutions was generally +accepted. In the meantime, Agricola's successors in the study of ore +deposits exhibited positive retrogression from the true fundamentals +advocated by him. Gesner, Utman, Meier, Lohneys, Barba, Rössler, Becher, +Stahl, Henckel, and Zimmerman, all fail to grasp the double essentials. +Other writers of this period often enough merely quote Agricola, some +not even acknowledging the source, as, for instance, Pryce (_Mineralogia +Cornubiensis_, London, 1778) and Williams (Natural History of the +Mineral Kingdom, London, 1789). After Von Oppel, the two fundamental +principles mentioned were generally accepted, but then arose the +complicated and acrimonious discussion of the origin of solutions, and +nothing in Agricola's view was so absurd as Werner's contention (_Neue +Theorie von der Entstehung der Gänge_, Freiberg, 1791) of the universal +chemical deluge which penetrated fissures open at the surface. While it +is not the purpose of these notes to pursue the history of these +subjects subsequent to the author's time, it is due to him and to the +current beliefs as to the history of the theory of ore deposits, to call +the attention of students to the perverse representation of Agricola's +views by Werner (op. cit.) upon which most writers have apparently +relied. Why this author should be (as, for instance, by Posepny, Amer. +Inst. Mining Engineers, 1901) so generally considered the father of our +modern theory, can only be explained by a general lack of knowledge of +the work of previous writers on ore deposition. Not one of the +propositions original with Werner still holds good, while his rejection +of the origin of solutions within the earth itself halted the march of +advance in thought on these subjects for half a century. It is our hope +to discuss exhaustively at some future time the development of the +history of this, one of the most far-reaching of geologic hypotheses. + +[2] The Latin _vena_, "vein," is also used by the author for ore; hence +this descriptive warning as to its intended double use. + +[3] The endeavour to discover the origin of the compass with the +Chinese, Arabs, or other Orientals having now generally ceased, together +with the idea that the knowledge of the lodestone involved any +acquaintance with the compass, it is permissible to take a rational view +of the subject. The lodestone was well known even before Plato and +Aristotle, and is described by Theophrastus (see Note 10, p. 115.) The +first authentic and specific mention of the compass appears to be by +Alexander Neckam (an Englishman who died in 1217), in his works _De +Utensilibus_ and _De Naturis Rerum_. The first tangible description of +the instrument was in a letter to Petrus Peregrinus de Maricourt, +written in 1269, a translation of which was published by Sir Sylvanus +Thompson (London, 1902). His circle was divided into four quadrants and +these quarters divided into 90 degrees each. The first mention of a +compass in connection with mines so far as we know is in the _Nützlich +Bergbüchlin_, a review of which will be found in Appendix B. This book, +which dates from 1500, gives a compass much like the one described above +by Agricola. It is divided in like manner into two halves of 12 +divisions each. The four cardinal points being marked _Mitternacht_, +_Morgen_, _Mittag_, and _Abend_. Thus the directions read were referred +to as II. after midnight, etc. According to Joseph Carne (Trans. Roy. +Geol. Socy. of Cornwall, Vol. II, 1814), the Cornish miners formerly +referred to North-South veins as 12 o'clock veins; South-East North-West +veins as 9 o'clock veins, etc. + +[4] _Crudariis._ Pliny (XXXIII., 31), says:--"_Argenti vena in summo +reperta crudaria appellatur._" "Silver veins discovered at the surface +are called _crudaria._" The German translator of Agricola uses the term +_sylber gang_--silver vein, obviously misunderstanding the author's +meaning. + +[5] It might be considered that the term "outcrop" could be used for +"head," but it will be noticed that a _vena dilatata_ would thus be +stated to have no outcrop. + +[6] It is possible that "veinlets" would be preferred by purists, but +the word "stringer" has become fixed in the nomenclature of miners and +we have adopted it. The old English term was "stringe," and appears in +Edward Manlove's "Rhymed Chronicle," London, 1653; Pryce's, _Mineralogia +Cornubiensis_, London, 1778, pp. 103 and 329; Mawe's "Mineralogy of +Devonshire," London, 1802, p. 210, etc., etc. + +[7] _Subdialis._ "In the open air." The Glossary gives the meaning as +_Ein tag klufft oder tag gehenge_--a surface stringer. + +[8] The following from Chapter IV of the _Nützlich Bergbüchlin_ (see +Appendix B) may indicate the source of the theory which Agricola here +discards:--"As to those veins which are most profitable to work, it must +be remarked that the most suitable location for the vein is on the slope +of the mountain facing south, so its strike is from VII or VI east to VI +or VII west. According to the above-mentioned directions, the outcrop of +the whole vein should face north, its _gesteins ausgang_ toward the +east, its hangingwall toward the south, and its footwall toward the +north, for in such mountains and veins the influence of the planets is +conveniently received to prepare the matter out of which the silver is +to be made or formed.... The other strikes of veins from between east +and south to the region between west and north are esteemed more or less +valuable, according to whether they are nearer or further away from the +above-mentioned strikes, but with the same hangingwall, footwall, and +outcrops. But the veins having their strike from north to south, their +hangingwall toward the west, their footwall and their outcrops toward +the east, are better to work than veins which extend from south to +north, whose hangingwalls are toward the east, and footwalls and +outcrops toward the west. Although the latter veins sometimes yield +solid and good silver ore, still it is not sure and certain, because the +whole mineral force is completely scattered and dispersed through the +outcrop, etc." + +[9] The names in the Latin are given as _Donum Divinum_--"God's Gift," +and _Coelestis Exercitus_--"Heavenly Host." The names given in the text +are from the German Translation. The former of these mines was located +in the valley of Joachim, where Agricola spent many years as the town +physician at Joachimsthal. It is of further interest, as Agricola +obtained an income from it as a shareholder. He gives the history of the +mine (_De Veteribus et Novis Metallis_, Book I.), as follows:--"The +mines at Abertham were discovered, partly by chance, partly by science. +In the eleventh year of Charles V. (1530), on the 18th of February, a +poor miner, but one skilled in the art of mining, dwelt in the middle of +the forest in a solitary hut, and there tended the cattle of his +employer. While digging a little trench in which to store milk, he +opened a vein. At once he washed some in a bowl and saw particles of the +purest silver settled at the bottom. Overcome with joy he informed his +employer, and went to the _Bergmeister_ and petitioned that official to +give him a head mining lease, which in the language of our people he +called _Gottsgaab_. Then he proceeded to dig the vein, and found more +fragments of silver, and the miners were inspired with great hopes as to +the richness of the vein. Although such hopes were not frustrated, still +a whole year was spent before they received any profits from the mine; +whereby many became discouraged and did not persevere in paying +expenses, but sold their shares in the mine; and for this reason, when +at last an abundance of silver was being drawn out, a great change had +taken place in the ownership of the mine; nay, even the first finder of +the vein was not in possession of any share in it, and had spent nearly +all the money which he had obtained from the selling of his shares. Then +this mine yielded such a quantity of pure silver as no other mine that +has existed within our own or our fathers' memories, with the exception +of the St. George at Schneeberg. We, as a shareholder, through the +goodness of God, have enjoyed the proceeds of this 'God's Gift' since +the very time when the mine began first to bestow such riches." Later on +in the same book he gives the following further information with regard +to these mines:--"Now if all the individual mines which have proved +fruitful in our own times are weighed in the balance, the one at +Annaberg, which is known as the _Himmelsch hoz_, surpasses all others. +For the value of the silver which has been dug out has been estimated at +420,000 Rhenish gulden. Next to this comes the lead mine in +Joachimsthal, whose name is the _Sternen_, from which as much silver has +been dug as would be equivalent to 350,000 Rhenish gulden; from the +Gottsgaab at Abertham, explained before, the equivalent of 300,000. But +far before all others within our fathers' memory stands the St. George +of Schneeberg, whose silver has been estimated as being equal to two +million Rhenish gulden." A Rhenish gulden was about 6.9 shillings, or, +say, $1.66. However, the ratio value of silver to gold at this period +was about 11.5 to one, or in other words an ounce of silver was worth +about a gulden, so that, for purposes of rough calculation, one might +say that the silver product mentioned in gulden is practically of the +same number of ounces of silver. Moreover, it must be remembered that +the purchasing power of money was vastly greater then. + +[10] The following passage occurs in the _Nützlich Bergbüchlin_ (Chap. +V.), which is interesting on account of the great similarity to +Agricola's quotation:--"The best position of the stream is when it has a +cliff beside it on the north and level ground on the south, but its +current should be from east to west--that is the most suitable. The next +best after this is from west to east, with the same position of the +rocks as already stated. The third in order is when the stream flows +from north to south with rocks toward the east, but the worst flow of +water for the preparation of gold is from south to north if a rock or +hill rises toward the west." Calbus was probably the author of this +booklet. + +[11] Albertus Magnus. + + + + +BOOK IV. + + +The third book has explained the various and manifold varieties of veins +and stringers. This fourth book will deal with mining areas and the +method of delimiting them, and will then pass on to the officials who +are connected with mining affairs[1]. + +Now the miner, if the vein he has uncovered is to his liking, first of +all goes to the _Bergmeister_ to request to be granted a right to mine, +this official's special function and office being to adjudicate in +respect of the mines. And so to the first man who has discovered the +vein the _Bergmeister_ awards the head meer, and to others the remaining +meers, in the order in which each makes his application. The size of a +meer is measured by fathoms, which for miners are reckoned at six feet +each. The length, in fact, is that of a man's extended arms and hands +measured across his chest; but different peoples assign to it different +lengths, for among the Greeks, who called it an [Greek: orguia], it was +six feet, among the Romans five feet. So this measure which is used by +miners seems to have come down to the Germans in accordance with the +Greek mode of reckoning. A miner's foot approaches very nearly to the +length of a Greek foot, for it exceeds it by only three-quarters of a +Greek digit, but like that of the Romans it is divided into twelve +_unciae_[2]. + +[Illustration 79a (Square with lengths and area): Shape of a Square +Meer.] + +Now square fathoms are reckoned in units of one, two, three, or more +"measures", and a "measure" is seven fathoms each way. Mining meers are +for the most part either square or elongated; in square meers all the +sides are of equal length, therefore the numbers of fathoms on the two +sides multiplied together produce the total in square fathoms. Thus, if +the shape of a "measure" is seven fathoms on every side, this number +multiplied by itself makes forty-nine square fathoms. + +[Illustration 79b (Rectangle with lengths and area): Shape of a Long +Meer or Double Measure.] + +The sides of a long meer are of equal length, and similarly its ends are +equal; therefore, if the number of fathoms in one of the long sides be +multiplied by the number of fathoms in one of the ends, the total +produced by the multiplication is the total number of square fathoms in +the long meer. For example, the double measure is fourteen fathoms long +and seven broad, which two numbers multiplied together make ninety-eight +square fathoms. + +[Illustration 79c (Rectangle with lengths and area): Shape of a Head +Meer.] + +Since meers vary in shape according to the different varieties of veins +it is necessary for me to go more into detail concerning them and their +measurements. If the vein is a _vena profunda_, the head meer is +composed of three double measures, therefore it is forty-two fathoms in +length and seven in width, which numbers multiplied together give two +hundred and ninety-four square fathoms, and by these limits the +_Bergmeister_ bounds the owner's rights in a head-meer. + +[Illustration 80a (Rectangle with lengths and area): Shape of a Meer.] + +The area of every other meer consists of two double measures, on +whichever side of the head meer it lies, or whatever its number in order +may be, that is to say, whether next to the head meer, or second, third, +or any later number. Therefore, it is twenty-eight fathoms long and +seven wide, so multiplying the length by the width we get one hundred +and ninety-six square fathoms, which is the extent of the meer, and by +these boundaries the _Bergmeister_ defines the right of the owner or +company over each mine. + +Now we call that part of the vein which is first discovered and mined, +the head-meer, because all the other meers run from it, just as the +nerves from the head. The _Bergmeister_ begins his measurements from it, +and the reason why he apportions a larger area to the head-meer than to +the others, is that he may give a suitable reward to the one who first +found the vein and may encourage others to search for veins. Since meers +often reach to a torrent, or river, or stream, if the last meer cannot +be completed it is called a fraction[3]. If it is the size of a double +measure, the _Bergmeister_ grants the right of mining it to him who +makes the first application, but if it is the size of a single measure +or a little over, he divides it between the nearest meers on either side +of it. It is the custom among miners that the first meer beyond a stream +on that part of the vein on the opposite side is a new head-meer, and +they call it the "opposite,"[4] while the other meers beyond are only +ordinary meers. Formerly every head-meer was composed of three double +measures and one single one, that is, it was forty-nine fathoms long and +seven wide, and so if we multiply these two together we have three +hundred and forty-three square fathoms, which total gives us the area of +an ancient head-meer. + +[Illustration 80b (Rectangle with lengths and area): Shape of an ancient +Head-Meer.] + +Every ancient meer was formed of a single measure, that is to say, it +was seven fathoms in length and width, and was therefore square. In +memory of which miners even now call the width of every meer which is +located on a _vena profunda_ a "square"[5]. The following was formerly +the usual method of delimiting a vein: as soon as the miner found +metal, he gave information to the _Bergmeister_ and the tithe-gatherer, +who either proceeded personally from the town to the mountains, or sent +thither men of good repute, at least two in number, to inspect the +metal-bearing vein. Thereupon, if they thought it of sufficient +importance to survey, the _Bergmeister_ again having gone forth on an +appointed day, thus questioned him who first found the vein, concerning +the vein and the diggings: "Which is your vein?" "Which digging carried +metal?" Then the discoverer, pointing his finger to his vein and +diggings, indicated them, and next the _Bergmeister_ ordered him to +approach the windlass and place two fingers of his right hand upon his +head, and swear this oath in a clear voice: "I swear by God and all the +Saints, and I call them all to witness, that this is my vein; and +moreover if it is not mine, may neither this my head nor these my hands +henceforth perform their functions." Then the _Bergmeister_, having +started from the centre of the windlass, proceeded to measure the vein +with a cord, and to give the measured portion to the discoverer,--in the +first instance a half and then three full measures; afterward one to the +King or Prince, another to his Consort, a third to the Master of the +Horse, a fourth to the Cup-bearer, a fifth to the Groom of the Chamber, +a sixth to himself. Then, starting from the other side of the windlass, +he proceeded to measure the vein in a similar manner. Thus the +discoverer of the vein obtained the head-meer, that is, seven single +measures; but the King or Ruler, his Consort, the leading dignitaries, +and lastly, the _Bergmeister_, obtained two measures each, or two +ancient meers. This is the reason there are to be found at Freiberg in +Meissen so many shafts with so many intercommunications on a single +vein--which are to a great extent destroyed by age. If, however, the +_Bergmeister_ had already fixed the boundaries of the meers on one side +of the shaft for the benefit of some other discoverer, then for those +dignitaries I have just mentioned, as many meers as he was unable to +award on that side he duplicated on the other. But if on both sides of +the shaft he had already defined the boundaries of meers, he proceeded +to measure out only that part of the vein which remained free, and thus +it sometimes happened that some of those persons I have mentioned +obtained no meer at all. To-day, though that old-established custom is +observed, the method of allotting the vein and granting title has been +changed. As I have explained above, the head-meer consists of three +double measures, and each other meer of two measures, and the +_Bergmeister_ grants one each of the meers to him who makes the first +application. The King or Prince, since all metal is taxed, is himself +content with that, which is usually one-tenth. + +Of the width of every meer, whether old or new, one-half lies on the +footwall side of a _vena profunda_ and one half on the hangingwall side. +If the vein descends vertically into the earth, the boundaries similarly +descend vertically; but if the vein inclines, the boundaries likewise +will be inclined. The owner always holds the mining right for the width +of the meer, however far the vein descends into the depth of the +earth.[6] Further, the _Bergmeister_, on application being made to him, +grants to one owner or company a right over not only the head meer, or +another meer, but also the head meer and the next meer or two adjoining +meers. So much for the shape of meers and their dimensions in the case +of a _vena profunda_. + +I now come to the case of _venae dilatatae_. The boundaries of the areas +on such veins are not all measured by one method. For in some places +the _Bergmeister_ gives them shapes similar to the shapes of the meers +on _venae profundae_, in which case the head-meer is composed of three +double measures, and the area of every other mine of two measures, as I +have explained more fully above. In this case, however, he measures the +meers with a cord, not only forward and backward from the ends of the +head-meer, as he is wont to do in the case where the owner of a _vena +profunda_ has a meer granted him, but also from the sides. In this way +meers are marked out when a torrent or some other force of Nature has +laid open a _vena dilatata_ in a valley, so that it appears either on +the slope of a mountain or hill or on a plain. Elsewhere the +_Bergmeister_ doubles the width of the head-meer and it is made fourteen +fathoms wide, while the width of each of the other meers remains single, +that is seven fathoms, but the length is not defined by boundaries. In +some places the head-meer consists of three double measures, but has a +width of fourteen fathoms and a length of twenty-one. + +[Illustration 86a (Rectangle with lengths): Shape of a Head-Meer.] + +[Illustration 86b (Square with lengths): Shape of every other Meer.] + +In the same way, every other meer is composed of two measures, doubled +in the same fashion, so that it is fourteen fathoms in width and of the +same length. + +Elsewhere every meer, whether a head-meer or other meer, comprises +forty-two fathoms in width and as many in length. + +In other places the _Bergmeister_ gives the owner or company all of some +locality defined by rivers or little valleys as boundaries. But the +boundaries of every such area of whatsoever shape it be, descend +vertically into the earth; so the owner of that area has a right over +that part of any _vena dilatata_ which lies beneath the first one, just +as the owner of the meer on a _vena profunda_ has a right over so great +a part of all other _venae profundae_ as lies within the boundaries of +his meer; for just as wherever one _vena profunda_ is found, another is +found not far away, so wherever one _vena dilatata_ is found, others are +found beneath it. + +Finally, the _Bergmeister_ divides _vena cumulata_ areas in different +ways, for in some localities the head-meer is composed of three +measures, doubled in such a way that it is fourteen fathoms wide and +twenty-one long; and every other meer consists of two measures doubled, +and is square, that is, fourteen fathoms wide and as many long. In some +places the head-meer is composed of three single measures, and its width +is seven fathoms and its length twenty-one, which two numbers multiplied +together make one hundred and forty-seven square fathoms. + +[Illustration 87 (Rectangle with lengths and area): Shape of a +Head-Meer.] + +Each other meer consists of one double measure. In some places the +head-meer is given the shape of a double measure, and every other meer +that of a single measure. Lastly, in other places the owner or a company +is given a right over some complete specified locality bounded by little +streams, valleys, or other limits. Furthermore, all meers on _venae +cumulatae_, as in the case of _dilatatae_, descend vertically into the +depths of the earth, and each meer has the boundaries so determined as +to prevent disputes arising between the owners of neighbouring mines. + +The boundary marks in use among miners formerly consisted only of +stones, and from this their name was derived, for now the marks of a +boundary are called "boundary stones." To-day a row of posts, made +either of oak or pine, and strengthened at the top with iron rings to +prevent them from being damaged, is fixed beside the boundary stones to +make them more conspicuous. By this method in former times the +boundaries of the fields were marked by stones or posts, not only as +written of in the book "_De Limitibus Agrorum_,"[7] but also as +testified to by the songs of the poets. Such then is the shape of the +meers, varying in accordance with the different kinds of veins. + +Now tunnels are of two sorts, one kind having no right of property, the +other kind having some limited right. For when a miner in some +particular locality is unable to open a vein on account of a great +quantity of water, he runs a wide ditch, open at the top and three feet +deep, starting on the slope and running up to the place where the vein +is found. Through it the water flows off, so that the place is made dry +and fit for digging. But if it is not sufficiently dried by this open +ditch, or if a shaft which he has now for the first time begun to sink +is suffering from overmuch water, he goes to the _Bergmeister_ and asks +that official to give him the right for a tunnel. Having obtained leave, +he drives the tunnel, and into its drains all the water is diverted, so +that the place or shaft is made fit for digging. If it is not seven +fathoms from the surface of the earth to the bottom of this kind of +tunnel, the owner possesses no rights except this one: namely, that the +owners of the mines, from whose leases the owner of the tunnel extracts +gold or silver, themselves pay him the sum he expends within their meer +in driving the tunnel through it. + +To a depth or height of three and a half fathoms above and below the +mouth of the tunnel, no one is allowed to begin another tunnel. The +reason for this is that this kind of a tunnel is liable to be changed +into the other kind which has a complete right of property, when it +drains the meers to a depth of seven fathoms, or to ten, according as +the old custom in each place acquires the force of law. In such case +this second kind of tunnel has the following right; in the first place, +whatever metal the owner, or company owning it, finds in any meer +through which it is driven, all belongs to the tunnel owner within a +height or depth of one and a quarter fathoms. In the years which are not +long passed, the owner of a tunnel possessed all the metal which a miner +standing at the bottom of the tunnel touched with a bar, whose handle +did not exceed the customary length; but nowadays a certain prescribed +height and width is allowed to the owner of the tunnel, lest the owners +of the mines be damaged, if the length of the bar be longer than usual. +Further, every metal-yielding mine which is drained and supplied with +ventilation by a tunnel, is taxed in the proportion of one-ninth for the +benefit of the owner of the tunnel. But if several tunnels of this kind +are driven through one mining area which is yielding metals, and all +drain it and supply it with ventilation, then of the metal which is dug +out from above the bottom of each tunnel, one-ninth is given to the +owner of that tunnel; of that which is dug out below the bottom of each +tunnel, one-ninth is in each case given to the owner of the tunnel which +follows next in order below. But if the lower tunnel does not yet drain +the shaft of that meer nor supply it with ventilation, then of the metal +which is dug out below the bottom of the higher tunnel, one-ninth part +is given to the owner of such upper tunnel. Moreover, no one tunnel +deprives another of its right to one-ninth part, unless it be a lower +one, from the bottom of which to the bottom of the one above must not be +less than seven or ten fathoms, according as the king or prince has +decreed. Further, of all the money which the owner of the tunnel has +spent on his tunnel while driving it through a meer, the owner of that +meer pays one-fourth part. If he does not do so he is not allowed to +make use of the drains. + +Finally, with regard to whatever veins are discovered by the owner at +whose expense the tunnel is driven, the right of which has not been +already awarded to anyone, on the application of such owner the +_Bergmeister_ grants him a right of a head-meer, or of a head-meer +together with the next meer. Ancient custom gives the right for a tunnel +to be driven in any direction for an unlimited length. Further, to-day +he who commences a tunnel is given, on his application, not only the +right over the tunnel, but even the head and sometimes the next meer +also. In former days the owner of the tunnel obtained only so much +ground as an arrow shot from the bow might cover, and he was allowed to +pasture cattle therein. In a case where the shafts of several meers on +some vein could not be worked on account of the great quantity of water, +ancient custom also allowed the _Bergmeister_ to grant the right of a +large meer to anyone who would drive a tunnel. When, however, he had +driven a tunnel as far as the old shafts and had found metal, he used to +return to the _Bergmeister_ and request him to bound and mark off the +extent of his right to a meer. Thereupon, the _Bergmeister_, together +with a certain number of citizens of the town--in whose place Jurors +have now succeeded--used to proceed to the mountain and mark off with +boundary stones a large meer, which consisted of seven double measures, +that is to say, it was ninety-eight fathoms long and seven wide, which +two numbers multiplied together make six hundred and eighty-six square +fathoms. + +[Illustration 89 (Rectangle with lengths and area): Large Area.] + +But each of these early customs has been changed, and we now employ the +new method. + +I have spoken of tunnels; I will now speak about the division of +ownership in mines and tunnels. One owner is allowed to possess and to +work one, two, three, or more whole meers, or similarly one or more +separate tunnels, provided he conforms to the decrees of the laws +relating to metals, and to the orders of the _Bergmeister_. And because +he alone provides the expenditure of money on the mines, if they yield +metal he alone obtains the product from them. But when large and +frequent expenditures are necessary in mining, he to whom the +_Bergmeister_ first gave the right often admits others to share with +him, and they join with him in forming a company, and they each lay out +a part of the expense and share with him the profit or loss of the mine. +But the title of the mines or tunnels remains undivided, although for +the purpose of dividing the expense and profit it may be said each mine +or tunnel is divided into parts[8]. + +This division is made in various ways. A mine, and the same thing must +be understood with regard to a tunnel, may be divided into two halves, +that is into two similar portions, by which method two owners spend an +equal amount on it and draw an equal profit from it, for each possesses +one half. Sometimes it is divided into four shares, by which compact +four persons can be owners, so that each possesses one-fourth, or also +two persons, so that one possesses three-fourths, and the other only +one-fourth; or three owners, so that the first has two-fourths, and the +second and third one-fourth each. Sometimes it is divided into eight +shares, by which plan there may be eight owners, so that each is +possessor of one-eighth; sometimes there are two owners, so that one has +five-sixths[9] together with one twenty-fourth, and the other +one-eighth; or there may be three owners, in which one has +three-quarters and the second and third each one-eighth; or it may be +divided so that one owner has seven-twelfths, together with one +twenty-fourth, a second owner has one-quarter, and a third owner has +one-eighth; or so that the first has one-half, the second one-third and +one twenty-fourth, and the third one-eighth; or so that the first has +one-half, as before, and the second and third each one-quarter; or so +that the first and second each have one-third and one twenty-fourth, and +the third one-quarter; and in the same way the divisions may be adjusted +in all the other proportions. The different ways of dividing the shares +originate from the different proportions of ownership. Sometimes a mine +is divided into sixteen parts, each of which is a twenty-fourth and a +forty-eighth; or it may be divided into thirty-two parts, each of which +is a forty-eighth and half a seventy-second and a two hundred and +eighty-eighth; or into sixty-four parts of which each share is one +seventy-second and one five hundred and seventy-sixth; or finally, into +one hundred and twenty-eight parts, any one of which is half a +seventy-second and half of one five hundred and seventy-sixth. + +Now an iron mine either remains undivided or is divided into two, four, +or occasionally more shares, which depends on the excellence of the +veins. But a lead, bismuth, or tin mine, and likewise one of copper or +even quicksilver, is also divided into eight shares, or into sixteen or +thirty-two, and less commonly into sixty-four. The number of the +divisions of the silver mines at Freiberg in Meissen did not formerly +progress beyond this; but within the memory of our fathers, miners have +divided a silver mine, and similarly the tunnel at Schneeberg, first of +all into one hundred and twenty-eight shares, of which one hundred and +twenty-six are the property of private owners in the mines or tunnels, +one belongs to the State and one to the Church; while in Joachimsthal +only one hundred and twenty-two shares of the mines or tunnels are the +property of private owners, four are proprietary shares, and the State +and Church each have one in the same way. To these there has lately been +added in some places one share for the most needy of the population, +which makes one hundred and twenty-nine shares. It is only the private +owners of mines who pay contributions. A proprietary holder, though he +holds as many as four shares such as I have described, does not pay +contributions, but gratuitiously supplies the owners of the mines with +sufficient wood from his forests for timbering, machinery, buildings, +and smelting; nor do those belonging to the State, Church, and the poor +pay contributions, but the proceeds are used to build or repair public +works and sacred buildings, and to support the most needy with the +profits which they draw from the mines. Furthermore, in our State, the +one hundred and twenty-eighth share has begun to be divided into two, +four, or eight parts, or even into three, six, twelve, or smaller parts. +This is done when one mine is created out of two, for then the owner who +formerly possessed one-half becomes owner of one-fourth; he who +possessed one-fourth, of one-eighth; he who possessed one-third, of +one-sixth; he who possessed one-sixth, of one-twelfth. Since our +countrymen call a mine a _symposium_, that is, a drinking bout, we are +accustomed to call the money which the owners subscribe a _symbolum_, or +a contribution[10]. For, just as those who go to a banquet (_symposium_) +give contributions (_symbola_), so those who purpose making large +profits from mining are accustomed to contribute toward the expenditure. +However, the manager of the mine assesses the contributions of the +owners annually, or for the most part quarterly, and as often he renders +an account of receipts and expenses. At Freiberg in Meissen the old +practice was for the manager to exact a contribution from the owners +every week, and every week to distribute among them the profits of the +mines, but this practice during almost the last fifteen years has been +so far changed that contribution and distribution are made four[11] +times each year. Large or small contributions are imposed according to +the number of workmen which the mine or tunnel requires; as a result, +those who possess many shares provide many contributions. Four times a +year the owners contribute to the cost, and four times during the year +the profits of the mines are distributed among them; these are sometimes +large, sometimes small, according as there is more or less gold or +silver or other metal dug out. Indeed, from the St. George mine in +Schneeberg the miners extracted so much silver in a quarter of a year +that silver cakes, which were worth 1,100 Rhenish guldens, were +distributed to each one hundred and twenty-eighth share. From the +Annaberg mine which is known as the Himmelisch Höz, they had a dole of +eight hundred thaler; from a mine in Joachimsthal which is named the +Sternen, three hundred thaler; from the head mine at Abertham, which is +called St. Lorentz, two hundred and twenty-five thaler[12]. The more +shares of which any individual is owner the more profits he takes. + +I will now explain how the owners may lose or obtain the right over a +mine, or a tunnel, or a share. Formerly, if anyone was able to prove by +witnesses that the owners had failed to send miners for three continuous +shifts[13], the _Bergmeister_ deprived them of their right over the +mine, and gave the right over it to the informer, if he desired it. But +although miners preserve this custom to-day, still mining share owners +who have paid their contributions do not lose their right over their +mines against their will. Formerly, if water which had not been drawn +off from the higher shaft of some mine percolated through a vein or +stringer into the shaft of another mine and impeded their work, then the +owners of the mine which suffered the damage went to the _Bergmeister_ +and complained of the loss, and he sent to the shafts two Jurors. If +they found that matters were as claimed, the right over the mine which +caused the injury was given to the owners who suffered the injury. But +this custom in certain places has been changed, for the _Bergmeister_, +if he finds this condition of things proved in the case of two shafts, +orders the owners of the shaft which causes the injury to contribute +part of the expense to the owners of the shaft which receives the +injury; if they fail to do so, he then deprives them of their right over +their mine; on the other hand, if the owners send men to the workings to +dig and draw off the water from the shafts, they keep their right over +their mine. Formerly owners used to obtain a right over any tunnel, +firstly, if in its bottom they made drains and cleansed them of mud and +sand so that the water might flow out without any hindrance, and +restored those drains which had been damaged; secondly, if they provided +shafts or openings to supply the miners with air, and restored those +which had fallen in; and finally, if three miners were employed +continuously in driving the tunnel. But the principal reason for losing +the title to a tunnel was that for a period of eight days no miner was +employed upon it; therefore, when anyone was able to prove by witnesses +that the owners of a tunnel had not done these things, he brought his +accusation before the _Bergmeister_, who, after going out from the town +to the tunnel and inspecting the drains and the ventilating machines and +everything else, and finding the charge to be true, placed the witness +under oath, and asked him: "Whose tunnel is this at the present time?" +The witness would reply: "The King's" or "The Prince's." Thereupon the +_Bergmeister_ gave the right over the tunnel to the first applicant. +This was the severe rule under which the owners at one time lost their +rights over a tunnel; but its severity is now considerably mitigated, +for the owners do not now forthwith lose their right over a tunnel +through not having cleaned out the drains and restored the shafts or +ventilation holes which have suffered damage; but the _Bergmeister_ +orders the tunnel manager to do it, and if he does not obey, the +authorities fine the tunnel. Also it is sufficient for one miner to be +engaged in driving the tunnel. Moreover, if the owner of a tunnel sets +boundaries at a fixed spot in the rocks and stops driving the tunnel, he +may obtain a right over it so far as he has gone, provided the drains +are cleaned out and ventilation holes are kept in repair. But any other +owner is allowed to start from the established mark and drive the tunnel +further, if he pays the former owners of the tunnel as much money every +three months as the _Bergmeister_ decides ought to be paid. + +There remain for discussion, the shares in the mines and tunnels. +Formerly if anybody conveyed these shares to anyone else, and the latter +had once paid his contribution, the seller[14] was bound to stand by his +bargain, and this custom to-day has the force of law. But if the seller +denied that the contribution had been paid, while the buyer of the +shares declared that he could prove by witnesses that he had paid his +contribution to the other proprietors, and a case arose for trial, then +the evidence of the other proprietors carried more weight than the oath +of the seller. To-day the buyer of the shares proves that he has paid +his contribution by a document which the mine or tunnel manager always +gives each one; if the buyer has contributed no money there is no +obligation on the seller to keep his bargain. Formerly, as I have said +above, the proprietors used to contribute money weekly, but now +contributions are paid four times each year. To-day, if for the space of +a month anyone does not take proceedings against the seller of the +shares for the contribution, the right of taking proceedings is lost. +But when the Clerk has already entered on the register the shares which +had been conveyed or bought, none of the owners loses his right over the +share unless the money is not contributed which the manager of the mine +or tunnel has demanded from the owner or his agent. Formerly, if on the +application of the manager the owner or his agent did not pay, the +matter was referred to the _Bergmeister_, who ordered the owner or his +agent to make his contribution; then if he failed to contribute for +three successive weeks, the _Bergmeister_ gave the right to his shares +to the first applicant. To-day this custom is unchanged, for if owners +fail for the space of a month to pay the contributions which the manager +of the mine has imposed on them, on a stated day their names are +proclaimed aloud and struck off the list of owners, in the presence of +the _Bergmeister_, the Jurors, the Mining Clerk, and the Share Clerk, +and each of such shares is entered on the proscribed list. If, however, +on the third, or at latest the fourth day, they pay their contributions +to the manager of the mine or tunnel, and pay the money which is due +from them to the Share Clerk, he removes their shares from the +proscribed list. They are not thereupon restored to their former +position unless the other owners consent; in which respect the custom +now in use differs from the old practice, for to-day if the owners of +shares constituting anything over half the mine consent to the +restoration of those who have been proscribed, the others are obliged to +consent whether they wish to or not. Formerly, unless such restoration +had been sanctioned by the approval of the owners of one hundred shares, +those who had been proscribed were not restored to their former +position. + +The procedure in suits relating to shares was formerly as follows: he +who instituted a suit and took legal proceedings against another in +respect of the shares, used to make a formal charge against the accused +possessor before the _Bergmeister_. This was done either at his house or +in some public place or at the mines, once each day for three days if +the shares belonged to an old mine, and three times in eight days if +they belonged to a head-meer. But if he could not find the possessor of +the shares in these places, it was valid and effectual to make the +accusation against him at the house of the _Bergmeister_. When, however, +he made the charge for the third time, he used to bring with him a +notary, whom the _Bergmeister_ would interrogate: "Have I earned the +fee?" and who would respond: "You have earned it"; thereupon the +_Bergmeister_ would give the right over the shares to him who made the +accusation, and the accuser in turn would pay down the customary fee to +the _Bergmeister_. After these proceedings, if the man whom the +_Bergmeister_ had deprived of his shares dwelt in the city, one of the +proprietors of the mine or of the head-mine was sent to him to acquaint +him with the facts, but if he dwelt elsewhere proclamation was made in +some public place, or at the mine, openly and in a loud voice in the +hearing of numbers of miners. Nowadays a date is defined for the one who +is answerable for the debt of shares or money, and information is given +the accused by an official if he is near at hand, or if he is absent, a +letter is sent him; nor is the right over his shares taken from anyone +for the space of one and a half months. So much for these matters. + +Now, before I deal with the methods which must be employed in working, I +will speak of the duties of the Mining Prefect, the _Bergmeister_, the +Jurors, the Mining Clerk, the Share Clerk, the manager of the mine or +tunnel, the foreman of the mine or tunnel, and the workmen. + +To the Mining Prefect, whom the King or Prince appoints as his deputy, +all men of all races, ages, and rank, give obedience and submission. He +governs and regulates everything at his discretion, ordering those +things which are useful and advantageous in mining operations, and +prohibiting those which are to the contrary. He levies penalties and +punishes offenders; he arranges disputes which the _Bergmeister_ has +been unable to settle, and if even he cannot arrange them, he allows the +owners who are at variance over some point to proceed to litigation; he +even lays down the law, gives orders as a magistrate, or bids them +leave their rights in abeyance, and he determines the pay of persons who +hold any post or office. He is present in person when the mine managers +present their quarterly accounts of profits and expenses, and generally +represents the King or Prince and upholds his dignity. The Athenians in +this way set Thucydides, the famous historian, over the mines of +Thasos[15]. + +Next in power to the Mining Prefect comes the _Bergmeister_, since he +has jurisdiction over all who are connected with mines, with a few +exceptions, which are the Tithe Gatherer, the Cashier, the Silver +Refiner, the Master of the Mint, and the Coiners themselves. Fraudulent, +negligent, or dissolute men he either throws into prison, or deprives of +promotion, or fines; of these fines, part is given as a tribute to those +in power. When the mine owners have a dispute over boundaries he +arbitrates it; or if he cannot settle the dispute, he pronounces +judgment jointly with the Jurors; from them, however, an appeal lies to +the Mining Prefect. He transcribes his decrees in a book and sets up the +records in public. It is also his duty to grant the right over the mines +to those who apply, and to confirm their rights; he also must measure +the mines, and fix their boundaries, and see that the mine workings are +not allowed to become dangerous. Some of these duties he observes on +fixed days; for on Wednesday in the presence of the Jurors he confirms +the rights over the mines which he has granted, settles disputes about +boundaries, and pronounces judgments. On Mondays, Tuesdays, Thursdays, +and Fridays, he rides up to the mines, and dismounting at some of them +explains what is required to be done, or considers the boundaries which +are under controversy. On Saturday all the mine managers and mine +foremen render an account of the money which they have spent on the +mines during the preceding week, and the Mining Clerk transcribes this +account into the register of expenses. Formerly, for one Principality +there was one _Bergmeister_, who used to create all the judges and +exercise jurisdiction and control over them; for every mine had its own +judge, just as to-day each locality has a _Bergmeister_ in his place, +the name alone being changed. To this ancient _Bergmeister_, who used to +dwell at Freiberg in Meissen, disputes were referred; hence right up to +the present time the one at Freiberg still has the power of pronouncing +judgment when mine owners who are engaged in disputes among themselves +appeal to him. The old _Bergmeister_ could try everything which was +presented to him in any mine whatsoever; whereas the judge could only +try the things which were done in his own district, in the same way that +every modern _Bergmeister_ can. + +To each _Bergmeister_ is attached a clerk, who writes out a schedule +signifying to the applicant for a right over a mine, the day and hour on +which the right is granted, the name of the applicant, and the location +of the mine. He also affixes at the entrance to the mine, quarterly, at +the appointed time, a sheet of paper on which is shown how much +contribution must be paid to the manager of the mine. These notices are +prepared jointly with the Mining Clerk, and in common they receive the +fee rendered by the foremen of the separate mines. + +I now come to the Jurors, who are men experienced in mining matters and +of good repute. Their number is greater or less as there are few or more +mines; thus if there are ten mines there will be five pairs of Jurors, +like a _decemviral college_[16]. Into however many divisions the total +number of mines has been divided, so many divisions has the body of +Jurors; each pair of Jurors usually visits some of the mines whose +administration is under their supervision on every day that workmen are +employed; it is usually so arranged that they visit all the mines in the +space of fourteen days. They inspect and consider all details, and +deliberate and consult with the mine foreman on matters relating to the +underground workings, machinery, timbering, and everything else. They +also jointly with the mine foreman from time to time make the price per +fathom to the workmen for mining the ore, fixing it at a high or low +price, according to whether the rock is hard or soft; if, however, the +contractors find that an unforeseen and unexpected hardness occurs, and +for that reason have difficulty and delay in carrying out their work, +the Jurors allow them something in excess of the price fixed; while if +there is a softness by reason of water, and the work is done more easily +and quickly, they deduct something from the price. Further, if the +Jurors discover manifest negligence or fraud on the part of any foreman +or workman, they first admonish or reprimand him as to his duties and +obligations, and if he does not become more diligent and improve, the +matter is reported to the _Bergmeister_, who by right of his authority +deprives such persons of their functions and office, or, if they have +committed a crime, throws them into prison. Lastly, because the Jurors +have been given to the _Bergmeister_ as councillors and advisors, in +their absence he does not confirm the right over any mine, nor measure +the mines, nor fix their boundaries, nor settle disputes about +boundaries, nor pronounce judgment, nor, finally, does he without them +listen to any account of profits and expenditure. + +Now the Mining Clerk enters each mine in his books, the new mines in one +book, the old mines which have been re-opened in another. This is done +in the following way: first is written the name of the man who has +applied for the right over the mine, then the day and hour on which he +made his application, then the vein and the locality in which it is +situated, next the conditions on which the right has been given, and +lastly, the day on which the _Bergmeister_ confirmed it. A document +containing all these particulars is also given to the person whose right +over a mine has been confirmed. The Mining Clerk also sets down in +another book the names of the owners of each mine over which the right +has been confirmed; in another any intermission of work permitted to any +person for certain reasons by the _Bergmeister_; in another the money +which one mine supplies to another for drawing off water or making +machinery; and in another the decisions of the _Bergmeister_ and the +Jurors, and the disputes settled by them as honorary arbitrators. All +these matters he enters in the books on Wednesday of every week; if +holidays fall on that day he does it on the following Thursday. Every +Saturday he enters in another book the total expenses of the preceding +week, the account of which the mine manager has rendered; but the total +quarterly expenses of each mine manager, he enters in a special book at +his own convenience. He enters similarly in another book a list of +owners who have been proscribed. Lastly, that no one may be able to +bring a charge of falsification against him, all these books are +enclosed in a chest with two locks, the key of one of which is kept by +the Mining Clerk, and of the other by the _Bergmeister_. + +The Share Clerk enters in a book the owners of each mine whom the first +finder of the vein names to him, and from time to time replaces the +names of the sellers with those of the buyers of the shares. It +sometimes happens that twenty or more owners come into the possession of +some particular share. Unless, however, the seller is present, or has +sent a letter to the Mining Clerk with his seal, or better still with +the seal of the Mayor of the town where he dwells, his name is not +replaced by that of anyone else; for if the Share Clerk is not +sufficiently cautious, the law requires him to restore the late owner +wholly to his former position. He writes out a fresh document, and in +this way gives proof of possession. Four times a year, when the accounts +of the quarterly expenditure are rendered, he names the new proprietors +to the manager of each mine, that the manager may know from whom he +should demand contributions and among whom to distribute the profits of +the mines. For this work the mine manager pays the Clerk a fixed fee. + +I will now speak of the duties of the mine manager. In the case of the +owners of every mine which is not yielding metal, the manager announces +to the proprietors their contributions in a document which is affixed to +the doors of the town hall, such contributions being large or small, +according as the _Bergmeister_ and two Jurors determine. If anyone fails +to pay these contributions for the space of a month, the manager removes +their names from the list of owners, and makes their shares the common +property of the other proprietors. And so, whomsoever the mine manager +names as not having paid his contribution, that same man the Mining +Clerk designates in writing, and so also does the Share Clerk. Of the +contribution, the mine manager applies part to the payment of the +foreman and workmen, and lays by a part to purchase at the lowest price +the necessary things for the mine, such as iron tools, nails, firewood, +planks, buckets, drawing-ropes, or grease. But in the case of a mine +which is yielding metal, the Tithe-gatherer pays the mine manager week +by week as much money as suffices to discharge the workmen's wages and +to provide the necessary implements for mining. The mine manager of each +mine also, in the presence of its foreman, on Saturday in each week +renders an account of his expenses to the _Bergmeister_ and the Jurors, +he renders an account of his receipts, whether the money has been +contributed by the owners or taken from the Tithe-gatherer; and of his +quarterly expenditure in the same way to them and to the Mining Prefect +and to the Mining Clerk, four times a year at the appointed time; for +just as there are four seasons of the year, namely, Spring, Summer, +Autumn, and Winter, so there are fourfold accounts of profits and +expenses. In the beginning of the first month of each quarter an account +is rendered of the money which the manager has spent on the mine during +the previous quarter, then of the profit which he has taken from it +during the same period; for example, the account which is rendered at +the beginning of spring is an account of all the profits and expenses of +each separate week of winter, which have been entered by the Mining +Clerk in the book of accounts. If the manager has spent the money of the +proprietors advantageously in the mine and has faithfully looked after +it, everyone praises him as a diligent and honest man; if through +ignorance in these matters he has caused loss, he is generally deprived +of his office; if by his carelessness and negligence the owners have +suffered loss, the _Bergmeister_ compels him to make good the loss; and +finally, if he has been guilty of fraud or theft, he is punished with +fine, prison, or death. Further, it is the business of the manager to +see that the foreman of the mine is present at the beginning and end of +the shifts, that he digs the ore in an advantageous manner, and makes +the required timbering, machines, and drains. The manager also makes the +deductions from the pay of the workmen whom the foreman has noted as +negligent. Next, if the mine is rich in metal, the manager must see that +its ore-house is closed on those days on which no work is performed; and +if it is a rich vein of gold or silver, he sees that the miners promptly +transfer the output from the shaft or tunnel into a chest or into the +strong room next to the house where the foreman dwells, that no +opportunity for theft may be given to dishonest persons. This duty he +shares in common with the foreman, but the one which follows is +peculiarly his own. When ore is smelted he is present in person, and +watches that the smelting is performed carefully and advantageously. If +from it gold or silver is melted out, when it is melted in the +cupellation furnace he enters the weight of it in his books and carries +it to the Tithe-gatherer, who similarly writes a note of its weight in +his books; it is then conveyed to the refiner. When it has been brought +back, both the Tithe-gatherer and manager again enter its weight in +their books. Why again? Because he looks after the goods of the owners +just as if they were his own. Now the laws which relate to mining permit +a manager to have charge of more than one mine, but in the case of mines +yielding gold or silver, to have charge of only two. If, however, +several mines following the head-mine begin to produce metal, he remains +in charge of these others until he is freed from the duty of looking +after them by the _Bergmeister_. Last of all, the manager, the +_Bergmeister_, and the two Jurors, in agreement with the owners, settle +the remuneration for the labourers. Enough of the duties and occupation +of the manager. + +I will now leave the manager, and discuss him who controls the workmen +of the mine, who is therefore called the foreman, although some call him +the watchman. It is he who distributes the work among the labourers, and +sees diligently that each faithfully and usefully performs his duties. +He also discharges workmen on account of incompetence, or negligence, +and supplies others in their places if the two Jurors and manager give +their consent. He must be skilful in working wood, that he may timber +shafts, place posts, and make underground structures capable of +supporting an undermined mountain, lest the rocks from the hangingwall +of the veins, not being supported, become detached from the mass of the +mountain and overwhelm the workmen with destruction. He must be able to +make and lay out the drains in the tunnels, into which the water from +the veins, stringers, and seams in the rocks may collect, that it may be +properly guided and can flow away. Further, he must be able to recognize +veins and stringers, so as to sink shafts to the best advantage, and +must be able to discern one kind of material which is mined from +another, or to train his subordinates that they may separate the +materials correctly. He must also be well acquainted with all methods of +washing, so as to teach the washers how the metalliferous earth or sand +is washed. He supplies the miners with iron tools when they are about to +start to work in the mines, and apportions a certain weight of oil for +their lamps, and trains them to dig to the best advantage, and sees that +they work faithfully. When their shift is finished, he takes back the +oil which has been left. On account of his numerous and important duties +and labours, only one mine is entrusted to one foreman, nay, rather +sometimes two or three foremen are set over one mine. + +Since I have mentioned the shifts, I will briefly explain how these are +carried on. The twenty-four hours of a day and night are divided into +three shifts, and each shift consists of seven hours. The three +remaining hours are intermediate between the shifts, and form an +interval during which the workmen enter and leave the mines. The first +shift begins at the fourth hour in the morning and lasts till the +eleventh hour; the second begins at the twelfth and is finished at the +seventh; these two are day shifts in the morning and afternoon. The +third is the night shift, and commences at the eighth hour in the +evening and finishes at the third in the morning. The _Bergmeister_ does +not allow this third shift to be imposed upon the workmen unless +necessity demands it. In that case, whether they draw water from the +shafts or mine the ore, they keep their vigil by the night lamps, and to +prevent themselves falling asleep from the late hours or from fatigue, +they lighten their long and arduous labours by singing, which is neither +wholly untrained nor unpleasing. In some places one miner is not allowed +to undertake two shifts in succession, because it often happens that he +either falls asleep in the mine, overcome by exhaustion from too much +labour, or arrives too late for his shift, or leaves sooner than he +ought. Elsewhere he is allowed to do so, because he cannot subsist on +the pay of one shift, especially if provisions grow dearer. The +_Bergmeister_ does not, however, forbid an extraordinary shift when he +concedes only one ordinary shift. When it is time to go to work the +sound of a great bell, which the foreigners call a "campana," gives the +workmen warning, and when this is heard they run hither and thither +through the streets toward the mines. Similarly, the same sound of the +bell warns the foreman that a shift has just been finished; therefore as +soon as he hears it, he stamps on the woodwork of the shaft and signals +the workmen to come out. Thereupon, the nearest as soon as they hear the +signal, strike the rocks with their hammers, and the sound reaches those +who are furthest away. Moreover, the lamps show that the shift has come +to an end when the oil becomes almost consumed and fails them. The +labourers do not work on Saturdays, but buy those things which are +necessary to life, nor do they usually work on Sundays or annual +festivals, but on these occasions devote the shift to holy things. +However, the workmen do not rest and do nothing if necessity demands +their labour; for sometimes a rush of water compels them to work, +sometimes an impending fall, sometimes something else, and at such times +it is not considered irreligious to work on holidays. Moreover, all +workmen of this class are strong and used to toil from birth. + +The chief kinds of workmen are miners, shovellers, windlass men, +carriers, sorters, washers, and smelters, as to whose duties I will +speak in the following books, in their proper place. At present it is +enough to add this one fact, that if the workmen have been reported by +the foreman for negligence, the _Bergmeister_, or even the foreman +himself, jointly with the manager, dismisses them from their work on +Saturday, or deprives them of part of their pay; or if for fraud, throws +them into prison. However, the owners of works in which the metals are +smelted, and the master of the smelter, look after their own men. As to +the government and duties of miners, I have now said enough; I will +explain them more fully in another work entitled _De Jure et Legibus +Metallicis_[17]. + + END OF BOOK IV. + + +FOOTNOTES: + +[1] The nomenclature in this chapter has given unusual difficulty, +because the organisation of mines, either past or present, in +English-speaking countries provides no exact equivalents for many of +these offices and for many of the legal terms. The Latin terms in the +text were, of course, coined by the author, and have no historical basis +to warrant their adoption, while the introduction of the original German +terms is open to much objection, as they are not only largely obsolete, +but also in the main would convey no meaning to the majority of readers. +We have, therefore, reached a series of compromises, and in the main +give the nearest English equivalent. Of much interest in this connection +is a curious exotic survival in mining law to be found in the High Peak +of Derbyshire. We believe (see note on p. 85) that the law of this +district was of Saxon importation, for in it are not only many terms of +German origin, but the character of the law is foreign to the older +English districts and shows its near kinship to that of Saxony. It is +therefore of interest in connection with the nomenclature to be adopted +in this book, as it furnishes about the only English precedents in many +cases. The head of the administration in the Peak was the Steward, who +was the chief judicial officer, with functions somewhat similar to the +_Berghauptmann_. However, the term Steward has come to have so much less +significance that we have adopted a literal rendering of the Latin. +Under the Steward was the Barmaster, Barghmaster, or Barmar, as he was +variously called, and his duties were similar to those of the +_Bergmeister_. The English term would seem to be a corruption of the +German, and as the latter has come to be so well understood by the +English-speaking mining class, we have in this case adopted the German. +The Barmaster acted always by the consent and with the approval of a +jury of from 12 to 24 members. In this instance the English had +functions much like a modern jury, while the _Geschwornen_ of Saxony had +much more widely extended powers. The German _Geschwornen_ were in the +main Inspectors; despite this, however, we have not felt justified in +adopting any other than the literal English for the Latin and German +terms. We have vacillated a great deal over the term _Praefectus +Fodinae_, the German _Steiger_ having, like the Cornish "Captain," in +these days degenerated into a foreman, whereas the duties as described +were not only those of the modern Superintendent or Manager, but also +those of Treasurer of the Company, for he made the calls on shares and +paid the dividends. The term Purser has been used for centuries in +English mining for the Accountant or Cashier, but his functions were +limited to paying dividends, wages, etc., therefore we have considered +it better not to adopt the latter term, and have compromised upon the +term Superintendent or Manager, although it has a distinctly modern +flavor. The word for _area_ has also caused much hesitation, and the +"meer" has finally been adopted with some doubt. The title described by +Agricola has a very close equivalent in the meer of old Derbyshire. As +will be seen later, the mines of Saxony were Regal property, and were +held subject to two essential conditions, _i.e._, payment of a tithe, +and continuous operation. This form of title thus approximates more +closely to the "lease" of Australia than to the old Cornish _sett_, or +the American _claim_. The _fundgrube_ of Saxony and Agricola's +equivalent, the _area capitis_--head lease--we have rendered literally +as "head meer," although in some ways "founders' meer" might be better, +for, in Derbyshire, this was called the "finder's" or founder's meer, +and was awarded under similar circumstances. It has also an analogy in +Australian law in the "reward" leases. The term "measure" has the merit +of being a literal rendering of the Latin, and also of being the +identical term in the same use in the High Peak. The following table of +the principal terms gives the originals of the Latin text, their German +equivalents according in the Glossary and other sources, and those +adopted in the translation:-- + + AGRICOLA. GERMAN GLOSSARY. TERM ADOPTED. + _Praefectus Metallorum_ _Bergamptmann_ Mining Prefect. + _Magister Metallicorum_ _Bergmeister_ Bergmeister. + _Scriba Magister _Bergmeister's schreiber_ Bergmeister's clerk. + Metallicorum_ + _Jurati_ _Geschwornen_ Jurates or Jurors. + _Publicus Signator_ _Gemeiner sigler_ Notary. + _Decumanus_ _Zehender_ Tithe gatherer. + _Distributor_ _Aussteiler_ Cashier. + _Scriba partium_ _Gegenschreiber_ Share clerk. + _Scriba fodinarum_ _Bergschreiber_ Mining clerk. + _Praefectus fodinae_ } _Steiger_ { Manager of the Mine. + _Praefectus cuniculi_ } { Manager of the Tunnel. + _Praeses fodinae_ } _Schichtmeister_ { Foreman of the Mine. + _Praeses cuniculi_ } { Foreman of the Tunnel. + _Fossores_ _Berghauer_ Miners or diggers. + _Ingestores_ _Berganschlagen_ Shovellers. + _Vectarii_ _Hespeler_ Lever workers + (windlass men). + _Discretores_ _Ertzpucher_ Sorters. + _Lotores_ _Wescher und seiffner_ Washers, buddlers, + sifters, etc. + _Excoctores_ _Schmeltzer_ Smelters. + _Purgator Argenti_ _Silber brenner_ Silver refiner. + _Magister Monetariorum_ _Müntzmeister_ Master of the Mint. + _Monetarius_ _Müntzer_ Coiner. + _Area fodinarum_ _Masse_ Meer. + _Area Capitis Fodinarum_ _Fundgrube_ Head meer. + _Demensum_ _Lehen_ Measure. + +[2] The following are the equivalents of the measures mentioned in this +book. It is not always certain which "foot" or "fathom" Agricola +actually had in mind although they were probably the German. + + Greek-- + _Dactylos_ = .76 inches + 16 = _Pous_ = 12.13 inches + 6 = _Orguia_ = 72.81 inches. + + Roman-- + _Uncia_ = .97 " + 12 = _Pes_ = 11.6 " + 5 = _Passus_ = 58.1 " + + German-- + _Zoll_ = .93 " + 12 = _Werckschuh_ = 11.24 " + 6 = _Lachter_ = 67.5 " + + English-- + Inch = 1.0 " + 12 = Foot = 12.00 " + 6 = Fathom = 72.0 " + +The discrepancies are due to variations in authorities and to decimals +dropped. The _werckschuh_ taken is the Chemnitz foot deduced from +Agricola's statement in his _De Mensuris et Ponderibus_, Basel, 1533, p. +29. For further notes see Appendix C. + +[3] _Subcisivum_--"Remainder." German Glossary, _Ueberschar_. The term +used in Mendip and Derbyshire was _primgap_ or _primegap_. It did not, +however, in this case belong to adjacent mines, but to the landlord. + +[4] _Adversum_. Glossary, _gegendrumb_. The _Bergwerk Lexicon_, +Chemnitz, 1743, gives _gegendrom_ or _gegentramm_, and defines it as the +_masse_ or lease next beyond a stream. + +[5] _Quadratum_. Glossary, _vierung_. The _vierung_ in old Saxon title +meant a definite zone on either side of the vein, 3-1/2 _lachter_ +(_lachter_ = 5 ft. 7.5 inches) into the hangingwall and the same into +the footwall, the length of one _vierung_ being 7 _lachter_ along the +strike. It must be borne in mind that the form of rights here referred +to entitled the miner to follow his vein, carrying the side line with +him in depth the same distance from the vein, in much the same way as +with the Apex Law of the United States. From this definition as given in +the _Bergwerk Lexicon_, p. 585, it would appear that the vein itself was +not included in the measurements, but that they started from the walls. + +[6] HISTORICAL NOTE ON THE DEVELOPMENT OF MINING LAW.--There is no +branch of the law of property, of which the development is more +interesting and illuminating from a social point of view than that +relating to minerals. Unlike the land, the minerals have ever been +regarded as a sort of fortuitous property, for the title of which there +have been four principal claimants--that is, the Overlord, as +represented by the King, Prince, Bishop, or what not; the Community or +the State, as distinguished from the Ruler; the Landowner; and the Mine +Operator, to which class belongs the Discoverer. The one of these that +possessed the dominant right reflects vividly the social state and +sentiment of the period. The Divine Right of Kings; the measure of +freedom of their subjects; the tyranny of the land-owning class; the +rights of the Community as opposed to its individual members; the rise +of individualism; and finally, the modern return to more communal view, +have all been reflected promptly in the mineral title. Of these parties +the claims of the Overlord have been limited only by the resistance of +his subjects; those of the State limited by the landlord; those of the +landlord by the Sovereign or by the State; while the miner, ever in a +minority in influence as well as in numbers, has been buffeted from +pillar to post, his only protection being the fact that all other +parties depended upon his exertion and skill. + +The conception as to which of these classes had a right in the title +have been by no means the same in different places at the same time, and +in all it varies with different periods; but the whole range of +legislation indicates the encroachment of one factor in the community +over another, so that their relative rights have been the cause of +never-ending contention, ever since a record of civil and economic +contentions began. In modern times, practically over the whole world, +the State has in effect taken the rights from the Overlord, but his +claims did not cease until his claims over the bodies of his subjects +also ceased. However, he still remains in many places with his picture +on the coinage. The Landlord has passed through many vicissitudes; his +complete right to minerals was practically never admitted until the +doctrine of _laissez-faire_ had become a matter of faith, and this just +in time to vest him with most of the coal and iron deposits in the +world; this, no doubt, being also partially due to the little regard in +which such deposits were generally held at that time, and therefore to +the little opposition to his ever-ready pretentions. Their numbers, +however, and their prominence in the support of the political powers _de +jure_ have usually obtained them some recognition. In the rise of +individualism, the apogee of the _laissez-faire_ fetish came about the +time of the foundation of the United States, and hence the relaxation in +the claims of the State in that country and the corresponding position +attained by the landlord and miner. The discoverer and the +operator--that is, the miner himself--has, however, had to be reckoned +with by all three of the other claimants, because they have almost +universally sought to escape the risks of mining, to obtain the most +skilful operation, and to stimulate the productivity of the mines; +thereupon the miner has secured at least partial consideration. This +stands out in all times and all places, and while the miner has had to +take the risks of his fortuitous calling, the Overlord, State, or +Landlord have all made for complacent safety by demanding some kind of a +tithe on his exertions. Moreover, there has often been a low cunning +displayed by these powers in giving something extra to the first +discoverer. In these relations of the powers to the mine operator, from +the very first we find definite records of the imposition of certain +conditions with extraordinary persistence--so fixed a notion that even +the United States did not quite escape it. This condition was, no doubt, +designed as a stimulus to productive activity, and was the requirement +that the miner should continuously employ himself digging in the piece +of ground allotted to him. The Greeks, Romans, Mediæval Germans, old and +modern Englishmen, modern Australians, all require the miner to keep +continuously labouring at his mines, or lose his title. The American, as +his inauguration of government happened when things were easier for +individuals, allows him a vacation of 11 months in the year for a few +years, and finally a holiday altogether. There are other points where +the Overlord, the State, or the Landlord have always considered that +they had a right to interfere, principally as to the way the miner does +his work, lest he should miss, or cause to be missed, some of the +mineral; so he has usually been under pains and penalties as to his +methods--these quite apart from the very proper protection to human +life, which is purely a modern invention, largely of the miner himself. +Somebody has had to keep peace and settle disputes among the usually +turbulent miners (for what other sort of operators would undertake the +hazards and handicaps?), and therefore special officials and codes, or +Courts, for his benefit are of the oldest and most persistent of +institutions. + +Between the Overlord and the Landowner the fundamental conflict of view +as to their respective rights has found its interpretation in the form +of the mineral title. The Overlord claimed the metals as distinguished +from the land, while the landowner claimed all beneath his soil. +Therefore, we find two forms of title--that in which the miner could +follow the ore regardless of the surface (the "apex" conception), and +that in which the boundaries were vertical from the land surface. Lest +the Americans think that the Apex Law was a sin original to themselves, +we may mention that it was made use of in Europe a few centuries before +Agricola, who will be found to set it out with great precision. + +From these points of view, more philosophical than legal, we present a +few notes on various ancient laws of mines, though space forbids a +discussion of a tithe of the amount it deserves at some experienced +hand. + +Of the Ancient Egyptian, Lydian, Assyrian, Persian, Indian, and Chinese +laws as to mines we have no record, but they were of great simplicity, +for the bodies as well as the property of subjects were at the abject +disposition of the Overlord. We are informed on countless occasions of +Emperors, Kings, and Princes of various degree among these races, owning +and operating mines with convicts, soldiers, or other slaves, so we may +take it for certain that continuous labour was enforced, and that the +boundaries, inspection, and landlords did not cause much anxiety. +However, herein lies the root of regalian right. + +Our first glimpse of a serious right of the subject to mines is among +some of the Greek States, as could be expected from their form of +government. With republican ideals, a rich mining district at Mount +Laurion, an enterprising and contentious people, it would be surprising +indeed if Athenian Literature was void on the subject. While we know +that the active operation of these mines extended over some 500 years, +from 700 to 200 B.C., the period of most literary reference was from 400 +to 300 B.C. Our information on the subject is from two of Demosthenes' +orations--one against Pantaenetus, the other against Phaenippus--the +first mining lawsuit in which the address of counsel is extant. There is +also available some information in Xenophon's Essay upon the Revenues, +Aristotle's Constitution of Athens, Lycurgus' prosecution of Diphilos, +the Tablets of the Poletae, and many incidental references and +inscriptions of minor order. The minerals were the property of the +State, a conception apparently inherited from the older civilizations. +Leases for exploitation were granted to individuals for terms of three +to ten years, depending upon whether the mines had been previously +worked, thus a special advantage was conferred upon the pioneer. The +leases did not carry surface rights, but the boundaries at Mt. Laurion +were vertical, as necessarily must be the case everywhere in horizontal +deposits. What they were elsewhere we do not know. The landlord +apparently got nothing. The miner must continuously operate his mine, +and was required to pay a large tribute to the State, either in the +initial purchase of his lease or in annual rent. There were elaborate +regulations as to interference and encroachment, and proper support of +the workings. Diphilos was condemned to death and his fortune +confiscated for robbing pillars. The mines were worked with slaves. + +The Romans were most intensive miners and searchers after metallic +wealth already mined. The latter was obviously the objective of most +Roman conquest, and those nations rich in these commodities, at that +time necessarily possessed their own mines. Thus a map showing the +extensions of Empire coincides in an extraordinary manner with the metal +distribution of Europe, Asia, and North Africa. Further, the great +indentations into the periphery of the Imperial map, though many were +rich from an agricultural point of view, had no lure to the Roman +because they had no mineral wealth. On the Roman law of mines the +student is faced with many perplexities. With the conquest of the older +States, the plunderers took over the mines and worked them, either by +leases from the State to public companies or to individuals; or even in +some cases worked them directly by the State. There was thus maintained +the concept of State ownership of the minerals which, although +apparently never very specifically defined, yet formed a basis of +support to the contention of regalian rights in Europe later on. +Parallel with this system, mines were discovered and worked by +individuals under tithe to the State, and in Pliny (XXXIV, 49) there is +reference to the miners in Britain limiting their own output. Individual +mining appears to have increased with any relaxation of central +authority, as for instance under Augustus. It appears, as a rule, that +the mines were held on terminable leases, and that the State did at +times resume them; the labour was mostly slaves. As to the detailed +conditions under which the mine operator held his title, we know less +than of the Greeks--in fact, practically nothing other than that he paid +a tithe. The Romans maintained in each mining district an official--the +_Procurator Metallorum_--who not only had general charge of the leasing +of the mines on behalf of the State, but was usually the magistrate of +the district. A bronze tablet found near Aljustrel, in Portugal, in +1876, generally known as the Aljustrel Tablet, appears to be the third +of a series setting out the regulations of the mining district. It +refers mostly to the regulation of public auctions, the baths, barbers, +and tradesmen; but one clause (VII.) is devoted to the regulation of +those who work dumps of scoria, etc., and provides for payment to the +administrator of the mines of a _capitation_ on the slaves employed. It +does not, however, so far as we can determine, throw any light upon the +actual regulations for working the mines. (Those interested will find +ample detail in Jacques Flach, "_La Table de Bronze d'Aljustrel: +Nouvelle Revue Historique de Droit Francais et Etranger_," 1878, p. 655; +_Estacio da Veiga, Memorias da Acad. Real das Ciencias de Lisbon, Nova +Scrie, Tome V, Part II_, Lisbon, 1882.) Despite the systematic law of +property evolved by the Romans, the codes contain but small reference to +mines, and this in itself is indirect evidence of the concept that they +were the property of the State. Any general freedom of the metals would +have given rise to a more extensive body of law. There are, of course, +the well-known sections in the Justinian and Theodosian Codes, but the +former in the main bears on the collection of the tithe and the +stimulation of mining by ordering migrant miners to return to their own +hearths. There is also some intangible prohibition of mining near +edifices. There is in the Theodosian code evident extension of +individual right to mine or quarry, and this "freeing" of the mines was +later considerably extended. The Empire was, however, then on the +decline; and no doubt it was hoped to stimulate the taxable commodities. +There is nothing very tangible as to the position of the landlord with +regard to minerals found on his property; the metals were probably of +insufficient frequency on the land of Italian landlords to matter much, +and the attitude toward subject races was not usually such as to require +an extensive body of law. + +In the chaos of the Middle Ages, Europe was governed by hundreds of +potentates, great and small, who were unanimous on one point, and this +that the minerals were their property. In the bickerings among +themselves, the stronger did not hesitate to interpret the Roman law in +affirming regalian rights as an excuse to dispossess the weaker. The +rights to the mines form no small part of the differences between these +Potentates and the more important of their subjects; and with the +gradual accretion of power into a few hands, we find only the most +powerful of vassals able to resist such encroachment. However, as to +what position the landlord or miner held in these rights, we have little +indication until about the beginning of the 13th century, after which +there appear several well-known charters, which as time went on were +elaborated into practical codes of mining law. The earliest of these +charters are those of the Bishop of Trent, 1185; that of the Harz +Miners, 1219; of the town of Iglau in 1249. Many such in connection with +other districts appear throughout the 13th, 14th, and 15th centuries. +(References to the most important of such charters may be found in +Sternberg, _Umrisse der Geschichte des Bergbaues_, Prague, 1838; +Eisenhart, _De Regali Metalli Fodinarium_, Helmestadt, 1681; Gmelin, +_Beyträge zur Geschichte des Teutschen Bergbaus_, Halle, 1783; +Inama-Sternegg, _Deutsche Wirthschaftsgeschichte_, Leipzig, 1879-1901; +Transactions, Royal Geol. Soc. Cornwall VI, 155; Lewis, The Stannaries, +New York, 1908.) By this time a number of mining communities had grown +up, and the charters in the main are a confirmation to them of certain +privileges; they contain, nevertheless, rigorous reservation of the +regalian right. The landlord, where present, was usually granted some +interest in the mine, but had to yield to the miner free entry. The +miner was simply a sort of tributer to the Crown, loaded with an +obligation when upon private lands to pay a further portion of his +profits to the landlord. He held tenure only during strenuous operation. +However, it being necessary to attract skilled men, they were granted +many civil privileges not general to the people; and from many of the +principal mining towns "free cities" were created, possessing a measure +of self-government. There appear in the Iglau charter of 1249 the first +symptoms of the "apex" form of title, this being the logical development +of the conception that the minerals were of quite distinct ownership +from the land. The law, as outlined by Agricola, is much the same as set +out in the Iglavian Charter of three centuries before, and we must +believe that such fully developed conceptions as that charter conveys +were but the confirmation of customs developed over generations. + +In France the landlord managed to maintain a stronger position +_vis-à-vis_ with the Crown, despite much assertion of its rights; and as +a result, while the landlord admitted the right to a tithe for the +Crown, he maintained the actual possession, and the boundaries were +defined with the land. + +In England the law varied with special mining communities, such as +Cornwall, Devon, the Forest of Dean, the Forest of Mendip, Alston Moor, +and the High Peak, and they exhibit a curious complex of individual +growth, of profound interest to the student of the growth of +institutions. These communities were of very ancient origin, some of +them at least pre-Roman; but we are, except for the reference in Pliny, +practically without any idea of their legal doings until after the +Norman occupation (1066 A.D.). The genius of these conquerors for +systematic government soon led them to inquire into the doings of these +communities, and while gradually systematising their customs into law, +they lost no occasion to assert the regalian right to the minerals. In +the two centuries subsequent to their advent there are on record +numerous inquisitions, with the recognition and confirmation of "the +customs and liberties which had existed from time immemorial," always +with the reservation to the Crown of some sort of royalty. Except for +the High Peak in Derbyshire, the period and origin of these "customs and +liberties" are beyond finding out, as there is practically no record of +English History between the Roman withdrawal and the Norman occupation. +There may have been "liberties" under the Romans, but there is not a +shred of evidence on the subject, and our own belief is that the forms +of self-government which sprang up were the result of the Roman +evacuation. The miner had little to complain of in the Norman treatment +in these matters; but between the Crown and the landlord as represented +by the Barons, Lords of the Manor, etc., there were wide differences of +opinion on the regalian rights, for in the extreme interpretation of the +Crown it tended greatly to curtail the landlord's position in the +matter, and the success of the Crown on this subject was by no means +universal. In fact, a considerable portion of English legal history of +mines is but the outcropping of this conflict, and one of the +concessions wrung from King John at Runnymede in 1215 was his +abandonment of a portion of such claims. + +The mining communities of Cornwall and Devon were early in the +13th century definitely chartered into corporations--"The +Stannaries"--possessing definite legislative and executive functions, +judicial powers, and practical self-government; but they were required +to make payment of the tithe in the shape of "coinage" on the tin. Such +recognition, while but a ratification of prior custom, was not obtained +without struggle, for the Norman Kings early asserted wide rights over +the mines. Tangible record of mining in these parts, from a legal point +of view, practically begins with a report by William de Wrotham in 1198 +upon his arrangements regarding the coinage. A charter of King John in +1201, while granting free right of entry to the miners, thus usurped the +rights of the landlords--a claim which he was compelled by the Barons to +moderate; the Crown, as above mentioned did maintain its right to a +royalty, but the landlord held the minerals. It is not, however, until +the time of Richard Carew's "Survey of Cornwall" (London, 1602) that we +obtain much insight into details of miners' title, and the customs there +set out were maintained in broad principle down to the 19th century. At +Carew's time the miner was allowed to prospect freely upon "Common" or +wastrel lands (since mostly usurped by landlords), and upon mineral +discovery marked his boundaries, within which he was entitled to the +vertical contents. Even upon such lands, however, he must acknowledge +the right of the lord of the manor to a participation in the mine. Upon +"enclosed" lands he had no right of entry without the consent of the +landlord; in fact, the minerals belonged to the land as they do to-day +except where voluntarily relinquished. In either case he was compelled +to "renew his bounds" once a year, and to operate more or less +continuously to maintain the right once obtained. There thus existed a +"labour condition" of variable character, usually imposed more or less +vigorously in the bargains with landlords. The regulations in Devonshire +differed in the important particular that the miner had right of entry +to private lands, although he was not relieved of the necessity to give +a participation of some sort to the landlord. The Forests of Dean, +Mendip, and other old mining communities possessed a measure of +self-government, which do not display any features in their law +fundamentally different from those of Cornwall and Devon. The High Peak +lead mines of Derbyshire, however, exhibit one of the most profoundly +interesting of these mining communities. As well as having distinctively +Saxon names for some of the mines, the customs there are of undoubted +Saxon origin, and as such their ratification by the Normans caused the +survival of one of the few Saxon institutions in England--a fact which, +we believe, has been hitherto overlooked by historians. Beginning with +inquisitions by Edward I. in 1288, there is in the Record Office a +wealth of information, the bare titles of which form too extensive a +list to set out here. (Of published works, the most important are Edward +Manlove's "The Liberties and Customs of the Lead Mines within the +Wapentake of Wirksworth," London, 1653, generally referred to as the +"Rhymed Chronicle"; Thomas Houghton, "Rara Avis in Terra," London, 1687; +William Hardy, "The Miner's Guide," Sheffield, 1748; Thomas Tapping, +"High Peak Mineral Customs," London, 1851.) The miners in this district +were presided over by a "Barmaster," "Barghmaster," or "Barmar," as he +was variously spelled, all being a corruption of the German Bergmeister, +with precisely the same functions as to the allotment of title, +settlement of disputes, etc., as his Saxon progenitor had, and, like +him, he was advised by a jury. The miners had entry to all lands except +churchyards (this regulation waived upon death), and a few similar +exceptions, and was subject to royalty to the Crown and the landlord. +The discoverer was entitled to a finder's "meer" of extra size, and his +title was to the vein within the end lines, _i.e._, the "apex" law. This +title was held subject to rigorous labour conditions, amounting to +forfeiture for failure to operate the mine for a period of nine weeks. +Space does not permit of the elaboration of the details of this subject, +which we hope to pursue elsewhere in its many historical bearings. Among +these we may mention that if the American "Apex law" is of English +descent, it must be laid to the door of Derbyshire, and not of Cornwall, +as is generally done. Our own belief, however, is that the American +"apex" conception came straight from Germany. + +It is not our purpose to follow these inquiries into mining law beyond +the 15th century, but we may point out that with the growth of the +sentiment of individualism the miners and landlords obtained steadily +wider and wider rights at the cost of the State, until well within the +19th century. The growth of stronger communal sentiment since the middle +of the last century has already found its manifestation in the +legislation with regard to mines, for the laws of South Africa, +Australia, and England, and the agitation in the United States are all +toward greater restrictions on the mineral ownership in favour of the +State. + +[7] ?_De Limitibus et de Re Agraria_ of Sextus Julius Frontinus (about +50-90 A.D.) + +[8] Such a form of ownership is very old. Apparently upon the +instigation of Xenophon (see Note 7, p. 29) the Greeks formed companies +to work the mines of Laurion, further information as to which is given +in note 6, p. 27. Pliny (Note 7, p. 232) mentions the Company working +the quicksilver mines in Spain. In fact, company organization was very +common among the Romans, who speculated largely in the shares, +especially in those companies which farmed the taxes of the provinces, +or leased public lands, or took military and civil contracts. + +[9] The Latin text gives one-sixth, obviously an error. + +[10] A _symposium_ is a banquet, and a _symbola_ is a contribution of +money to a banquet. This sentence is probably a play on the old German +_Zeche_, mine, this being also a term for a drinking bout. + +[11] In the Latin text this is "three"--obviously an error. + +[12] See Note 9, p. 74, for further information with regard to these +mines. The Rhenish gulden was about 6.9 shillings, or $1.66. Silver was +worth about this amount per Troy ounce at this period, so that roughly, +silver of a value of 1,100 gulden would be about 1,100 Troy ounces. The +Saxon thaler was worth about 4.64 shillings or about $1.11. The thaler, +therefore, represented about .65 Troy ounces of silver, so that 300 +thalers were about 195 Troy ounces, and 225 thalers about 146 Troy +ounces. + +[13] _Opera continens_. The Glossary gives _schicht_,--the origin of the +English "shift." + +[14] The terms in the Latin text are _donator_, a giver of a gift, and +_donatus_, a receiver. It appears to us, however, that some +consideration passed, and we have, therefore, used "seller" and "buyer." + +[15] See Note 29, p. 23. + +[16] _Decemviri_--"The Ten Men." The original _Decemviri_ were a body +appointed by the Romans in 452 B.C., principally to codify the law. Such +commissions were afterward instituted for other purposes, but the +analogy of the above paragraph is a little remote. + +[17] This work was apparently never published; see Appendix A. + + + + +BOOK V. + + +In the last book I have explained the methods of delimiting the meers +along each kind of vein, and the duties of mine officials. In this +book[1] I will in like manner explain the principles of underground +mining and the art of surveying. First then, I will proceed to deal with +those matters which pertain to the former heading, since both the +subject and methodical arrangement require it. And so I will describe +first of all the digging of shafts, tunnels, and drifts on _venae +profundae_; next I will discuss the good indications shown by +_canales_[2], by the materials which are dug out, and by the rocks; then +I will speak of the tools by which veins and rocks are broken down and +excavated; the method by which fire shatters the hard veins; and +further, of the machines with which water is drawn from the shafts and +air is forced into deep shafts and long tunnels, for digging is impeded +by the inrush of the former or the failure of the latter; next I will +deal with the two kinds of shafts, and with the making of them and of +tunnels; and finally, I will describe the method of mining _venae +dilatatae_, _venae cumulatae_, and stringers. + +Now when a miner discovers a _vena profunda_ he begins sinking a shaft +and above it sets up a windlass, and builds a shed over the shaft to +prevent the rain from falling in, lest the men who turn the windlass be +numbed by the cold or troubled by the rain. The windlass men also place +their barrows in it, and the miners store their iron tools and other +implements therein. Next to the shaft-house another house is built, +where the mine foreman and the other workmen dwell, and in which are +stored the ore and other things which are dug out. Although some persons +build only one house, yet because sometimes boys and other living things +fall into the shafts, most miners deliberately place one house apart +from the other, or at least separate them by a wall. + +[Illustration 103 (Shafts): Three vertical shafts, of which the first, +A, does not reach the tunnel; the second, B, reaches the tunnel; to the +third, C, the tunnel has not yet been driven. D--Tunnel.] + +[Illustration 104 (Shafts): Three inclined shafts, of which A does not +yet reach the tunnel; B reaches the tunnel; to the third, C, the tunnel +has not yet been driven. D--Tunnel.] + +Now a shaft is dug, usually two fathoms long, two-thirds of a fathom +wide, and thirteen fathoms deep; but for the purpose of connecting with +a tunnel which has already been driven in a hill, a shaft may be sunk to +a depth of only eight fathoms, at other times to fourteen, more or +less[3]. A shaft may be made vertical or inclined, according as the vein +which the miners follow in the course of digging is vertical or +inclined. A tunnel is a subterranean ditch driven lengthwise, and is +nearly twice as high as it is broad, and wide enough that workmen and +others may be able to pass and carry their loads. It is usually one and +a quarter fathoms high, while its width is about three and +three-quarters feet. Usually two workmen are required to drive it, one +of whom digs out the upper and the other the lower part, and the one +goes forward, while the other follows closely after. Each sits upon +small boards fixed securely from the footwall to the hangingwall, or if +the vein is a soft one, sometimes on a wedge-shaped plank fixed on to +the vein itself. Miners sink more inclined shafts than vertical, and +some of each kind do not reach to tunnels, while some connect with them. +But as for some shafts, though they have already been sunk to the +required depth, the tunnel which is to pierce the mountain may not yet +have been driven far enough to connect with them. + +[Illustration 105 (Shafts): A--Shaft. B, C--Drift. D--Another shaft. +E--Tunnel. F--Mouth of tunnel.] + +It is advantageous if a shaft connects with a tunnel, for then the +miners and other workmen carry on more easily the work they have +undertaken; but if the shaft is not so deep, it is usual to drift from +one or both sides of it. From these openings the owner or foreman +becomes acquainted with the veins and stringers that unite with the +principal vein, or cut across it, or divide it obliquely; however, my +discourse is now concerned mainly with _vena profunda_, but most of all +with the metallic material which it contains. Excavations of this kind +were called by the Greeks [Greek: kryptai] for, extending along after +the manner of a tunnel, they are entirely hidden within the ground. +This kind of an opening, however, differs from a tunnel in that it is +dark throughout its length, whereas a tunnel has a mouth open to +daylight. + +I have spoken of shafts, tunnels, and drifts. I will now speak of the +indications given by the _canales_, by the materials which are dug out, +and by the rocks. These indications, as also many others which I will +explain, are to a great extent identical in _venae dilatatae_ and _venae +cumulatae_ with _venae profundae_. + +When a stringer junctions with a main vein and causes a swelling, a +shaft should be sunk at the junction. But when we find the stringer +intersecting the main vein crosswise or obliquely, if it descends +vertically down to the depths of the earth, a second shaft should be +sunk to the point where the stringer cuts the main vein; but if the +stringer cuts it obliquely the shaft should be two or three fathoms +back, in order that the junction may be pierced lower down. At such +junctions lies the best hope of finding the ore for the sake of which we +explore the ground, and if ore has already been found, it is usually +found in much greater abundance at that spot. Again, if several +stringers descend into the earth, the miner, in order to pierce through +the point of contact, should sink the shaft in the midst of these +stringers, or else calculate on the most prominent one. + +Since an inclined vein often lies near a vertical vein, it is advisable +to sink a shaft at the spot where a stringer or cross-vein cuts them +both; or where a _vena dilatata_ or a stringer _dilatata_ passes +through, for minerals are usually found there. In the same way we have a +good prospect of finding metal at the point where an inclined vein joins +a vertical one; this is why miners cross-cut the hangingwall or footwall +of a main vein, and in these openings seek for a vein which may junction +with the principal vein a few fathoms below. Nay, further, these same +miners, if no stringer or cross-vein intersects the main vein so that +they can follow it in their workings, even cross-cut through the solid +rock of the hangingwall or footwall. These cross-cuts are likewise +called "[Greek: kryptai]," whether the beginning of the opening which +has to be undertaken is made from a tunnel or from a drift. Miners have +some hope when only a cross vein cuts a main vein. Further, if a vein +which cuts the main vein obliquely does not appear anywhere beyond it, +it is advisable to dig into that side of the main vein toward which the +oblique vein inclines, whether the right or left side, that we may +ascertain if the main vein has absorbed it; if after cross-cutting six +fathoms it is not found, it is advisable to dig on the other side of the +main vein, that we may know for certain whether it has carried it +forward. The owners of a main vein can often dig no less profitably on +that side where the vein which cuts the main vein again appears, than +where it first cuts it; the owners of the intersecting vein, when that +is found again, recover their title, which had in a measure been lost. + +The common miners look favourably upon the stringers which come from the +north and join the main vein; on the other hand, they look unfavourably +upon those which come from the south, and say that these do much harm to +the main vein, while the former improve it. But I think that miners +should not neglect either of them: as I showed in Book III, experience +does not confirm those who hold this opinion about veins, so now again +I could furnish examples of each kind of stringers rejected by the +common miners which have proved good, but I know this could be of little +or no benefit to posterity. + +If the miners find no stringers or veins in the hangingwall or footwall +of the main vein, and if they do not find much ore, it is not worth +while to undertake the labour of sinking another shaft. Nor ought a +shaft to be sunk where a vein is divided into two or three parts, unless +the indications are satisfactory that those parts may be united and +joined together a little later. Further, it is a bad indication for a +vein rich in mineral to bend and turn hither and thither, for unless it +goes down again into the ground vertically or inclined, as it first +began, it produces no more metal; and even though it does go down again, +it often continues barren. Stringers which in their outcrops bear +metals, often disappoint miners, no metal being found in depth. Further, +inverted seams in the rocks are counted among the bad indications. + +The miners hew out the whole of solid veins when they show clear +evidence of being of good quality; similarly they hew out the drusy[4] +veins, especially if the cavities are plainly seen to have formerly +borne metal, or if the cavities are few and small. They do not dig +barren veins through which water flows, if there are no metallic +particles showing; occasionally, however, they dig even barren veins +which are free from water, because of the pyrites which is devoid of all +metal, or because of a fine black soft substance which is like wool. +They dig stringers which are rich in metal, or sometimes, for the +purpose of searching for the vein, those that are devoid of ore which +lie near the hangingwall or footwall of the main vein. This then, +generally speaking, is the mode of dealing with stringers and veins. + +Let us now consider the metallic material which is found in the +_canales_ of _venae profundae_, _venae dilatatae_, and _venae +cumulatae_, being in all these either cohesive and continuous, or +scattered and dispersed among them, or swelling out in bellying shapes, +or found in veins or stringers which originate from the main vein and +ramify like branches; but these latter veins and stringers are very +short, for after a little space they do not appear again. If we come +across a small quantity of metallic material it is an indication; but if +a large quantity, it is not an "indication," but the very thing for +which we explore the earth. As soon as a miner who searches for veins +discovers pure metal or minerals, or rich metallic material, or a great +abundance of material which is poor in metal, let him sink a shaft on +the spot without any delay. If the material appears more abundant or of +better quality on the one side, he will incline his digging in that +direction. + +Gold, silver, copper, and quicksilver are often found native[5]; less +often iron and bismuth; almost never tin and lead. Nevertheless +tin-stone is not far removed from the pure white tin which is melted out +of them, and galena, from which lead is obtained, differs little from +that metal itself. + +Now we may classify gold ores. Next after native gold, we come to the +_rudis_[6], of yellowish green, yellow, purple, black, or outside red +and inside gold colour. These must be reckoned as the richest ores, +because the gold exceeds the stone or earth in weight. Next come all +gold ores of which each one hundred _librae_ contains more than three +_unciae_ of gold[7]; for although but a small proportion of gold is +found in the earth or stone, yet it equals in value other metals of +greater weight.[8] All other gold ores are considered poor, because the +earth or stone too far outweighs the gold. A vein which contains a +larger proportion of silver than of gold is rarely found to be a rich +one. Earth, whether it be dry or wet, rarely abounds in gold; but in dry +earth there is more often found a greater quantity of gold, especially +if it has the appearance of having been melted in a furnace, and if it +is not lacking in scales resembling mica. The solidified juices, azure, +chrysocolla, orpiment, and realgar, also frequently contain gold. +Likewise native or _rudis_ gold is found sometimes in large, and +sometimes in small quantities in quartz, schist, marble, and also in +stone which easily melts in fire of the second degree, and which is +sometimes so porous that it seems completely decomposed. Lastly, gold is +found in pyrites, though rarely in large quantities. + +When considering silver ores other than native silver, those ores are +classified as rich, of which each one hundred _librae_ contains more +than three _librae_ of silver. This quality comprises _rudis_ silver, +whether silver glance or ruby silver, or whether white, or black, or +grey, or purple, or yellow, or liver-coloured, or any other. Sometimes +quartz, schist, or marble is of this quality also, if much native or +_rudis_ silver adheres to it. But that ore is considered of poor quality +if three _librae_ of silver at the utmost are found in each one hundred +_librae_ of it[9]. Silver ore usually contains a greater quantity than +this, because Nature bestows quantity in place of quality; such ore is +mixed with all kinds of earth and stone compounds, except the various +kinds of _rudis_ silver; especially with pyrites, _cadmia metallica +fossilis_, galena, _stibium_, and others. + +As regards other kinds of metal, although some rich ores are found, +still, unless the veins contain a large quantity of ore, it is very +rarely worth while to dig them. The Indians and some other races do +search for gems in veins hidden deep in the earth, but more often they +are noticed from their clearness, or rather their brilliancy, when +metals are mined. When they outcrop, we follow veins of marble by mining +in the same way as is done with rock or building-stones when we come +upon them. But gems, properly so called, though they sometimes have +veins of their own, are still for the most part found in mines and rock +quarries, as the lodestone in iron mines, the emery in silver mines, the +_lapis judaicus_, _trochites_, and the like in stone quarries where the +diggers, at the bidding of the owners, usually collect them from the +seams in the rocks.[10] Nor does the miner neglect the digging of +"extraordinary earths,"[11] whether they are found in gold mines, +silver mines, or other mines; nor do other miners neglect them if they +are found in stone quarries, or in their own veins; their value is +usually indicated by their taste. Nor, lastly, does the miner fail to +give attention to the solidified juices which are found in metallic +veins, as well as in their own veins, from which he collects and gathers +them. But I will say no more on these matters, because I have explained +more fully all the metals and mineral substances in the books "_De +Natura Fossilium_." + +But I will return to the indications. If we come upon earth which is +like lute, in which there are particles of any sort of metal, native or +_rudis_, the best possible indication of a vein is given to miners, for +the metallic material from which the particles have become detached is +necessarily close by. But if this kind of earth is found absolutely +devoid of all metallic material, but fatty, and of white, green, blue, +and similar colours, they must not abandon the work that has been +started. Miners have other indications in the veins and stringers, which +I have described already, and in the rocks, about which I will speak a +little later. If the miner comes across other dry earths which contain +native or _rudis_ metal, that is a good indication; if he comes across +yellow, red, black, or some other "extraordinary" earth, though it is +devoid of mineral, it is not a bad indication. Chrysocolla, or azure, or +verdigris, or orpiment, or realgar, when they are found, are counted +among the good indications. Further, where underground springs throw up +metal we ought to continue the digging we have begun, for this points to +the particles having been detached from the main mass like a fragment +from a body. In the same way the thin scales of any metal adhering to +stone or rock are counted among the good indications. Next, if the veins +which are composed partly of quartz, partly of clayey or dry earth, +descend one and all into the depths of the earth together, with their +stringers, there is good hope of metal being found; but if the stringers +afterward do not appear, or little metallic material is met with, the +digging should not be given up until there is nothing remaining. Dark or +black or horn or liver-coloured quartz is usually a good sign; white is +sometimes good, sometimes no sign at all. But calc-spar, showing itself +in a _vena profunda_, if it disappears a little lower down is not a good +indication; for it did not belong to the vein proper, but to some +stringer. Those kinds of stone which easily melt in fire, especially if +they are translucent (fluorspar?), must be counted among the medium +indications, for if other good indications are present they are good, +but if no good indications are present, they give no useful +significance. In the same way we ought to form our judgment with regard +to gems. Veins which at the hangingwall and footwall have horn-coloured +quartz or marble, but in the middle clayey earth, give some hope; +likewise those give hope in which the hangingwall or footwall shows +iron-rust coloured earth, and in the middle greasy and sticky earth; +also there is hope for those which have at the hanging or footwall that +kind of earth which we call "soldiers' earth," and in the middle black +earth or earth which looks as if burnt. The special indication of gold +is orpiment; of silver is bismuth and _stibium_; of copper is verdigris, +_melanteria_, _sory_, _chalcitis_, _misy_, and vitriol; of tin is the +large pure black stones of which the tin itself is made, and a material +they dig up resembling litharge; of iron, iron rust. Gold and copper are +equally indicated by chrysocolla and azure; silver and lead, by the +lead. But, though miners rightly call bismuth "the roof of silver," and +though copper pyrites is the common parent of vitriol and _melanteria_, +still these sometimes have their own peculiar minerals, just as have +orpiment and _stibium_. + +Now, just as certain vein materials give miners a favourable indication, +so also do the rocks through which the _canales_ of the veins wind their +way, for sand discovered in a mine is reckoned among the good +indications, especially if it is very fine. In the same way schist, when +it is of a bluish or blackish colour, and also limestone, of whatever +colour it may be, is a good sign for a silver vein. There is a rock of +another kind that is a good sign; in it are scattered tiny black stones +from which tin is smelted; especially when the whole space between the +veins is composed of this kind of rock. Very often indeed, this good +kind of rock in conjunction with valuable stringers contains within its +folds the _canales_ of mineral bearing veins: if it descends vertically +into the earth, the benefit belongs to that mine in which it is seen +first of all; if inclined, it benefits the other neighbouring mines[12]. +As a result the miner who is not ignorant of geometry can calculate from +the other mines the depth at which the _canales_ of a vein bearing rich +metal will wind its way through the rock into his mine. So much for +these matters. + +I now come to the mode of working, which is varied and complex, for in +some places they dig crumbling ore, in others hard ore, in others a +harder ore, and in others the hardest kind of ore. In the same way, in +some places the hangingwall rock is soft and fragile, in others hard, in +others harder, and in still others of the hardest sort. I call that ore +"crumbling" which is composed of earth, and of soft solidified juices; +that ore "hard" which is composed of metallic minerals and moderately +hard stones, such as for the most part are those which easily melt in a +fire of the first and second orders, like lead and similar materials. I +call that ore "harder" when with those I have already mentioned are +combined various sorts of quartz, or stones which easily melt in fire of +the third degree, or pyrites, or _cadmia_, or very hard marble. I call +that ore hardest, which is composed throughout the whole vein of these +hard stones and compounds. The hanging or footwalls of a vein are hard, +when composed of rock in which there are few stringers or seams; harder, +in which they are fewer; hardest, in which they are fewest or none at +all. When these are absent, the rock is quite devoid of water which +softens it. But the hardest rock of the hanging or footwall, however, is +seldom as hard as the harder class of ore. + +Miners dig out crumbling ore with the pick alone. When the metal has not +yet shown itself, they do not discriminate between the hangingwall and +the veins; when it has once been found, they work with the utmost care. +For first of all they tear away the hangingwall rock separately from the +vein, afterward with a pick they dislodge the crumbling vein from the +footwall into a dish placed underneath to prevent any of the metal from +falling to the ground. They break a hard vein loose from the footwall by +blows with a hammer upon the first kind of iron tool[13], all of which +are designated by appropriate names, and with the same tools they hew +away the hard hangingwall rock. They hew out the hangingwall rock in +advance more frequently, the rock of the footwall more rarely; and +indeed, when the rock of the footwall resists iron tools, the rock of +the hangingwall certainly cannot be broken unless it is allowable to +shatter it by fire. With regard to the harder veins which are tractable +to iron tools, and likewise with regard to the harder and hardest kind +of hangingwall rock, they generally attack them with more powerful iron +tools, in fact, with the fourth kind of iron tool, which are called by +their appropriate names; but if these are not ready to hand, they use +two or three iron tools of the first kind together. As for the hardest +kind of metal-bearing vein, which in a measure resists iron tools, if +the owners of the neighbouring mines give them permission, they break it +with fires. But if these owners refuse them permission, then first of +all they hew out the rock of the hangingwall, or of the footwall if it +be less hard; then they place timbers set in hitches in the hanging or +footwall, a little above the vein, and from the front and upper part, +where the vein is seen to be seamed with small cracks, they drive into +one of the little cracks one of the iron tools which I have mentioned; +then in each fracture they place four thin iron blocks, and in order to +hold them more firmly, if necessary, they place as many thin iron plates +back to back; next they place thinner iron plates between each two iron +blocks, and strike and drive them by turns with hammers, whereby the +vein rings with a shrill sound; and the moment when it begins to be +detached from the hangingwall or footwall rock, a tearing sound is +heard. As soon as this grows distinct the miners hastily flee away; then +a great crash is heard as the vein is broken and torn, and falls down. +By this method they throw down a portion of a vein weighing a hundred +pounds more or less. But if the miners by any other method hew the +hardest kind of vein which is rich in metal, there remain certain +cone-shaped portions which can be cut out afterward only with +difficulty. As for this knob of hard ore, if it is devoid of metal, or +if they are not allowed to apply fire to it, they proceed round it by +digging to the right or left, because it cannot be broken into by iron +wedges without great expense. Meantime, while the workmen are carrying +out the task they have undertaken, the depths of the earth often resound +with sweet singing, whereby they lighten a toil which is of the severest +kind and full of the greatest dangers. + +As I have just said, fire shatters the hardest rocks, but the method of +its application is not simple[14]. For if a vein held in the rocks +cannot be hewn out because of the hardness or other difficulty, and the +drift or tunnel is low, a heap of dried logs is placed against the rock +and fired; if the drift or tunnel is high, two heaps are necessary, of +which one is placed above the other, and both burn until the fire has +consumed them. This force does not generally soften a large portion of +the vein, but only some of the surface. When the rock in the hanging or +footwall can be worked by the iron tools and the vein is so hard that it +is not tractable to the same tools, then the walls are hollowed out; if +this be in the end of the drift or tunnel or above or below, the vein is +then broken by fire, but not by the same method; for if the hollow is +wide, as many logs are piled into it as possible, but if narrow, only a +few. By the one method the greater fire separates the vein more +completely from the footwall or sometimes from the hangingwall, and by +the other, the smaller fire breaks away less of the vein from the rock, +because in that case the fire is confined and kept in check by portions +of the rock which surround the wood held in such a narrow excavation. +Further, if the excavation is low, only one pile of logs is placed in +it, if high, there are two, one placed above the other, by which plan +the lower bundle being kindled sets alight the upper one; and the fire +being driven by the draught into the vein, separates it from the rock +which, however hard it may be, often becomes so softened as to be the +most easily breakable of all. Applying this principle, Hannibal, the +Carthaginian General, imitating the Spanish miners, overcame the +hardness of the Alps by the use of vinegar and fire. Even if a vein is a +very wide one, as tin veins usually are, miners excavate into the small +streaks, and into those hollows they put dry wood and place amongst them +at frequent intervals sticks, all sides of which are shaved down +fan-shaped, which easily take light, and when once they have taken fire +communicate it to the other bundles of wood, which easily ignite. + +[Illustration 120 (Fire-setting): A--Kindled logs. B--Sticks shaved down +fan-shaped. C--Tunnel.] + +While the heated veins and rock are giving forth a foetid vapour and the +shafts or tunnels are emitting fumes, the miners and other workmen do +not go down in the mines lest the stench affect their health or actually +kill them, as I will explain in greater detail when I come to speak of +the evils which affect miners. The _Bergmeister_, in order to prevent +workmen from being suffocated, gives no one permission to break veins or +rock by fire in shafts or tunnels where it is possible for the poisonous +vapour and smoke to permeate the veins or stringers and pass through +into the neighbouring mines, which have no hard veins or rock. As for +that part of a vein or the surface of the rock which the fire has +separated from the remaining mass, if it is overhead, the miners +dislodge it with a crowbar, or if it still has some degree of hardness, +they thrust a smaller crowbar into the cracks and so break it down, but +if it is on the sides they break it with hammers. Thus broken off, the +rock tumbles down; or if it still remains, they break it off with picks. +Rock and earth on the one hand, and metal and ore on the other, are +filled into buckets separately and drawn up to the open air or to the +nearest tunnel. If the shaft is not deep, the buckets are drawn up by a +machine turned by men; if it is deep, they are drawn by machines turned +by horses. + +It often happens that a rush of water or sometimes stagnant air hinders +the mining; for this reason miners pay the greatest attention to these +matters, just as much as to digging, or they should do so. The water of +the veins and stringers and especially of vacant workings, must be +drained out through the shafts and tunnels. Air, indeed, becomes +stagnant both in tunnels and in shafts; in a deep shaft, if it be by +itself, this occurs if it is neither reached by a tunnel nor connected +by a drift with another shaft; this occurs in a tunnel if it has been +driven too far into a mountain and no shaft has yet been sunk deep +enough to meet it; in neither case can the air move or circulate. For +this reason the vapours become heavy and resemble mist, and they smell +of mouldiness, like a vault or some underground chamber which has been +completely closed for many years. This suffices to prevent miners from +continuing their work for long in these places, even if the mine is full +of silver or gold, or if they do continue, they cannot breathe freely +and they have headaches; this more often happens if they work in these +places in great numbers, and bring many lamps, which then supply them +with a feeble light, because the foul air from both lamps and men make +the vapours still more heavy. + +A small quantity of water is drawn from the shafts by machines of +different kinds which men turn or work. If so great a quantity has +flowed into one shaft as greatly to impede mining, another shaft is sunk +some fathoms distant from the first, and thus in one of them work and +labour are carried on without hindrance, and the water is drained into +the other, which is sunk lower than the level of the water in the first +one; then by these machines or by those worked by horses, the water is +drawn up into the drain and flows out of the shaft-house or the mouth of +the nearest tunnel. But when into the shaft of one mine, which is sunk +more deeply, there flows all the water of all the neighbouring mines, +not only from that vein in which the shaft is sunk, but also from other +veins, then it becomes necessary for a large sump to be made to collect +the water; from this sump the water is drained by machines which draw it +through pipes, or by ox-hides, about which I will say more in the next +book. The water which pours into the tunnels from the veins and +stringers and seams in the rocks is carried away in the drains. + +Air is driven into the extremities of deep shafts and long tunnels by +powerful blowing machines, as I will explain in the following book, +which will deal with these machines also. The outer air flows +spontaneously into the caverns of the earth, and when it can pass +through them comes out again. This, however, comes about in different +ways, for in spring and summer it flows into the deeper shafts, +traverses the tunnels or drifts, and finds its way out of the shallower +shafts; similarly at the same season it pours into the lowest tunnel +and, meeting a shaft in its course, turns aside to a higher tunnel and +passes out therefrom; but in autumn and winter, on the other hand, it +enters the upper tunnel or shaft and comes out at the deeper ones. This +change in the flow of air currents occurs in temperate regions at the +beginning of spring and the end of autumn, but in cold regions at the +end of spring and the beginning of autumn. But at each period, before +the air regularly assumes its own accustomed course, generally for a +space of fourteen days it undergoes frequent variations, now blowing +into an upper shaft or tunnel, now into a lower one. But enough of this, +let us now proceed to what remains. + +There are two kinds of shafts, one of the depth already described, of +which kind there are usually several in one mine; especially if the mine +is entered by a tunnel and is metal-bearing. For when the first tunnel +is connected with the first shaft, two new shafts are sunk; or if the +inrush of water hinders sinking, sometimes three are sunk; so that one +may take the place of a sump and the work of sinking which has been +begun may be continued by means of the remaining two shafts; the same is +done in the case of the second tunnel and the third, or even the fourth, +if so many are driven into a mountain. The second kind of shaft is very +deep, sometimes as much as sixty, eighty, or one hundred fathoms. These +shafts continue vertically toward the depths of the earth, and by means +of a hauling-rope the broken rock and metalliferous ores are drawn out +of the mine; for which reason miners call them vertical shafts. Over +these shafts are erected machines by which water is extracted; when they +are above ground the machines are usually worked by horses, but when +they are in tunnels, other kinds are used which are turned by +water-power. Such are the shafts which are sunk when a vein is rich in +metal. + +Now shafts, of whatever kind they may be, are supported in various ways. +If the vein is hard, and also the hanging and footwall rock, the shaft +does not require much timbering, but timbers are placed at intervals, +one end of each of which is fixed in a hitch cut into the rock of the +hangingwall and the other fixed into a hitch cut in the footwall. To +these timbers are fixed small timbers along the footwall, to which are +fastened the lagging and ladders. The lagging is also fixed to the +timbers, both to those which screen off the shaft on the ends from the +vein, and to those which screen off the rest of the shaft from that part +in which the ladders are placed. The lagging on the sides of the shaft +confine the vein, so as to prevent fragments of it which have become +loosened by water from dropping into the shaft and terrifying, or +injuring, or knocking off the miners and other workmen who are going up +or down the ladders from one part of the mine to another. For the same +reason, the lagging between the ladders and the haulage-way on the other +hand, confine and shut off from the ladders the fragments of rock which +fall from the buckets or baskets while they are being drawn up; +moreover, they make the arduous and difficult descent and ascent to +appear less terrible, and in fact to be less dangerous. + +[Illustration 123 (Timbering Shafts): A--Wall plates. B--Dividers. +C--Long end posts. D--End plates.] + +If a vein is soft and the rock of the hanging and footwalls is weak, a +closer structure is necessary; for this purpose timbers are joined +together, in rectangular shapes and placed one after the other without a +break. These are arranged on two different systems; for either the +square ends of the timbers, which reach from the hangingwall to the +footwall, are fixed into corresponding square holes in the timbers which +lie along the hanging or footwall, or the upper part of the end of one +and the lower part of the end of the other are cut out and one laid on +the other. The great weight of these joined timbers is sustained by +stout beams placed at intervals, which are deeply set into hitches in +the footwall and hangingwall, but are inclined. In order that these +joined timbers may remain stationary, wooden wedges or poles cut from +trees are driven in between the timbers and the vein and the hangingwall +and the footwall; and the space which remains empty is filled with loose +dirt. If the hanging and footwall rock is sometimes hard and sometimes +soft, and the vein likewise, solid joined timbers are not used, but +timbers are placed at intervals; and where the rock is soft and the vein +crumbling, carpenters put in lagging between them and the wall rocks, +and behind these they fill with loose dirt; by this means they fill up +the void. + +When a very deep shaft, whether vertical or inclined, is supported by +joined timbers, then, since they are sometimes of bad material and a +fall is threatened, for the sake of greater firmness three or four pairs +of strong end posts are placed between these, one pair on the +hangingwall side, the other on the footwall side. To prevent them from +falling out of position and to make them firm and substantial, they are +supported by frequent end plates, and in order that these may be more +securely fixed they are mortised into the posts. Further, in whatever +way the shaft may be timbered, dividers are placed upon the wall plates, +and to these is fixed lagging, and this marks off and separates the +ladder-way from the remaining part of the shaft. If a vertical shaft is +a very deep one, planks are laid upon the timbers by the side of the +ladders and fixed on to the timbers, in order that the men who are going +up or down may sit or stand upon them and rest when they are tired. To +prevent danger to the shovellers from rocks which, after being drawn up +from so deep a shaft fall down again, a little above the bottom of the +shaft small rough sticks are placed close together on the timbers, in +such a way as to cover the whole space of the shaft except the +ladder-way. A hole, however, is left in this structure near the +footwall, which is kept open so that there may be one opening to the +shaft from the bottom, that the buckets full of the materials which have +been dug out may be drawn from the shaft through it by machines, and may +be returned to the same place again empty; and so the shovellers and +other workmen, as it were hiding beneath this structure, remain +perfectly safe in the shaft. + +[Illustration 125 (Timbering Tunnels): A--Posts. B--Caps. C--Sills. +D--Doors. E--Lagging. F--Drains.] + +In mines on one vein there are driven one, two, or sometimes three or +more tunnels, always one above the other. If the vein is solid and hard, +and likewise the hanging and footwall rock, no part of the tunnel needs +support, beyond that which is required at the mouth, because at that +spot there is not yet solid rock; if the vein is soft, and the hanging +and footwall rock are likewise soft, the tunnel requires frequent strong +timbering, which is provided in the following way. First, two dressed +posts are erected and set into the tunnel floor, which is dug out a +little; these are of medium thickness, and high enough that their ends, +which are cut square, almost touch the top of the tunnel; then upon them +is placed a smaller dressed cap, which is mortised into the heads of the +posts; at the bottom, other small timbers, whose ends are similarly +squared, are mortised into the posts. At each interval of one and a half +fathoms, one of these sets is erected; each one of these the miners call +a "little doorway," because it opens a certain amount of passage way; +and indeed, when necessity requires it, doors are fixed to the timbers +of each little doorway so that it can be closed. Then lagging of planks +or of poles is placed upon the caps lengthwise, so as to reach from one +set of timbers to another, and is laid along the sides, in case some +portion of the body of the mountain may fall, and by its bulk impede +passage or crush persons coming in or out. Moreover, to make the timbers +remain stationary, wooden pegs are driven between them and the sides of +the tunnel. Lastly, if rock or earth are carried out in wheelbarrows, +planks joined together are laid upon the sills; if the rock is hauled +out in trucks, then two timbers three-quarters of a foot thick and wide +are laid on the sills, and, where they join, these are usually hollowed +out so that in the hollow, as in a road, the iron pin of the truck may +be pushed along; indeed, because of this pin in the groove, the truck +does not leave the worn track to the left or right. Beneath the sills +are the drains through which the water flows away. + +Miners timber drifts in the same way as tunnels. These do not, however, +require sill-pieces, or drains; for the broken rock is not hauled very +far, nor does the water have far to flow. If the vein above is +metal-bearing, as it sometimes is for a distance of several fathoms, +then from the upper part of tunnels or even drifts that have already +been driven, other drifts are driven again and again until that part of +the vein is reached which does not yield metal. The timbering of these +openings is done as follows: stulls are set at intervals into hitches in +the hanging and footwall, and upon them smooth poles are laid +continuously; and that they may be able to bear the weight, the stulls +are generally a foot and a half thick. After the ore has been taken out +and the mining of the vein is being done elsewhere, the rock then +broken, especially if it cannot be taken away without great difficulty, +is thrown into these openings among the timber, and the carriers of the +ore are saved toil, and the owners save half the expense. This then, +generally speaking, is the method by which everything relating to the +timbering of shafts, tunnels, and drifts is carried out. + +All that I have hitherto written is in part peculiar to _venae +profundae_, and in part common to all kinds of veins; of what follows, +part is specially applicable to _venae dilatatae_, part to _venae +cumulatae_. But first I will describe how _venae dilatatae_ should be +mined. Where torrents, rivers, or streams have by inundations washed +away part of the slope of a mountain or a hill, and have disclosed a +_vena dilatata_, a tunnel should be driven first straight and narrow, +and then wider, for nearly all the vein should be hewn away; and when +this tunnel has been driven further, a shaft which supplies air should +be sunk in the mountain or hill, and through it from time to time the +ore, earth, and rock can be drawn up at less expense than if they be +drawn out through the very great length of the tunnel; and even in those +places to which the tunnel does not yet reach, miners dig shafts in +order to open a _vena dilatata_ which they conjecture must lie beneath +the soil. In this way, when the upper layers are removed, they dig +through rock sometimes of one kind and colour, sometimes of one kind but +different colours, sometimes of different kinds but of one colour, and, +lastly, of different kinds and different colours. The thickness of rock, +both of each single stratum and of all combined, is uncertain, for the +whole of the strata are in some places twenty fathoms deep, in others +more than fifty; individual strata are in some places half a foot thick; +in others, one, two, or more feet; in others, one, two, three, or more +fathoms. For example, in those districts which lie at the foot of the +Harz mountains, there are many different coloured strata, covering a +copper _vena dilatata_. When the soil has been stripped, first of all is +disclosed a stratum which is red, but of a dull shade and of a thickness +of twenty, thirty, or five and thirty fathoms. Then there is another +stratum, also red, but of a light shade, which has usually a thickness +of about two fathoms. Beneath this is a stratum of ash-coloured clay +nearly a fathom thick, which, although it is not metalliferous, is +reckoned a vein. Then follows a third stratum, which is ashy, and about +three fathoms thick. Beneath this lies a vein of ashes to the thickness +of five fathoms, and these ashes are mixed with rock of the same colour. +Joined to the last, and underneath, comes a stratum, the fourth in +number, dark in colour and a foot thick. Under this comes the fifth +stratum, of a pale or yellowish colour, two feet thick; underneath +which is the sixth stratum, likewise dark, but rough and three feet +thick. Afterward occurs the seventh stratum, likewise of dark colour, +but still darker than the last, and two feet thick. This is followed by +an eighth stratum, ashy, rough, and a foot thick. This kind, as also the +others, is sometimes distinguished by stringers of the stone which +easily melts in fire of the second order. Beneath this is another ashy +rock, light in weight, and five feet thick. Next to this comes a lighter +ash-coloured one, a foot thick; beneath this lies the eleventh stratum, +which is dark and very much like the seventh, and two feet thick. Below +the last is a twelfth stratum of a whitish colour and soft, also two +feet thick; the weight of this rests on a thirteenth stratum, ashy and +one foot thick, whose weight is in turn supported by a fourteenth +stratum, which is blackish and half a foot thick. There follows this, +another stratum of black colour, likewise half a foot thick, which is +again followed by a sixteenth stratum still blacker in colour, whose +thickness is also the same. Beneath this, and last of all, lies the +cupriferous stratum, black coloured and schistose, in which there +sometimes glitter scales of gold-coloured pyrites in the very thin +sheets, which, as I said elsewhere, often take the forms of various +living things.[15] + +The miners mine out a _vena dilatata_ laterally and longitudinally by +driving a low tunnel in it, and if the nature of the work and place +permit, they sink also a shaft in order to discover whether there is a +second vein beneath the first one; for sometimes beneath it there are +two, three, or more similar metal-bearing veins, and these are excavated +in the same way laterally and longitudinally. They generally mine _venae +dilatatae_ lying down; and to avoid wearing away their clothes and +injuring their left shoulders they usually bind on themselves small +wooden cradles. For this reason, this particular class of miners, in +order to use their iron tools, are obliged to bend their necks to the +left, not infrequently having them twisted. Now these veins also +sometimes divide, and where these parts re-unite, ore of a richer and a +better quality is generally found; the same thing occurs where the +stringers, of which they are not altogether devoid, join with them, or +cut them crosswise, or divide them obliquely. To prevent a mountain or +hill, which has in this way been undermined, from subsiding by its +weight, either some natural pillars and arches are left, on which the +pressure rests as on a foundation, or timbering is done for support. +Moreover, the materials which are dug out and which are devoid of metal +are removed in bowls, and are thrown back, thus once more filling the +caverns. + +Next, as to _venae cumulatae_. These are dug by a somewhat different +method, for when one of these shows some metal at the top of the ground, +first of all one shaft is sunk; then, if it is worth while, around this +one many shafts are sunk and tunnels are driven into the mountain. If a +torrent or spring has torn fragments of metal from such a vein, a tunnel +is first driven into the mountain or hill for the purpose of searching +for the ore; then when it is found, a vertical shaft is sunk in it. +Since the whole mountain, or more especially the whole hill, is +undermined, seeing that the whole of it is composed of ore, it is +necessary to leave the natural pillars and arches, or the place is +timbered. But sometimes when a vein is very hard it is broken by fire, +whereby it happens that the soft pillars break up, or the timbers are +burnt away, and the mountain by its great weight sinks into itself, and +then the shaft buildings are swallowed up in the great subsidence. +Therefore, about a _vena cumulata_ it is advisable to sink some shafts +which are not subject to this kind of ruin, through which the materials +that are excavated may be carried out, not only while the pillars and +underpinnings still remain whole and solid, but also after the supports +have been destroyed by fire and have fallen. Since ore which has thus +fallen must necessarily be broken by fire, new shafts through which the +smoke can escape must be sunk in the abyss. At those places where +stringers intersect, richer ore is generally obtained from the mine; +these stringers, in the case of tin mines, sometimes have in them black +stones the size of a walnut. If such a vein is found in a plain, as not +infrequently happens in the case of iron, many shafts are sunk, because +they cannot be sunk very deep. The work is carried on by this method +because the miners cannot drive a tunnel into a level plain of this +kind. + +There remain the stringers in which gold alone is sometimes found, in +the vicinity of rivers and streams, or in swamps. If upon the soil being +removed, many of these are found, composed of earth somewhat baked and +burnt, as may sometimes be seen in clay pits, there is some hope that +gold may be obtained from them, especially if several join together. But +the very point of junction must be pierced, and the length and width +searched for ore, and in these places very deep shafts cannot be sunk. + +I have completed one part of this book, and now come to the other, in +which I will deal with the art of surveying. Miners measure the solid +mass of the mountains in order that the owners may lay out their plans, +and that their workmen may not encroach on other people's possessions. +The surveyor either measures the interval not yet wholly dug through, +which lies between the mouth of a tunnel and a shaft to be sunk to that +depth, or between the mouth of a shaft and the tunnel to be driven to +that spot which lies under the shaft, or between both, if the tunnel is +neither so long as to reach to the shaft, nor the shaft so deep as to +reach to the tunnel; and thus on both sides work is still to be done. Or +in some cases, within the tunnels and drifts, are to be fixed the +boundaries of the meers, just as the _Bergmeister_ has determined the +boundaries of the same meers above ground.[16] + +Each method of surveying depends on the measuring of triangles. A small +triangle should be laid out, and from it calculations must be made +regarding a larger one. Most particular care must be taken that we do +not deviate at all from a correct measuring; for if, at the beginning, +we are drawn by carelessness into a slight error, this at the end will +produce great errors. Now these triangles are of many shapes, since +shafts differ among themselves and are not all sunk by one and the same +method into the depths of the earth, nor do the slopes of all mountains +come down to the valley or plain in the same manner. For if a shaft is +vertical, there is a triangle with a right angle, which the Greeks call +[Greek: orthogônion] and this, according to the inequalities of the +mountain slope, has either two equal sides or three unequal sides. The +Greeks call the former [Greek: trigônon isoskeles] the latter [Greek: +skalênon] for a right angle triangle cannot have three equal sides. If a +shaft is inclined and sunk in the same vein in which the tunnel is +driven, a triangle is likewise made with a right angle, and this again, +according to the various inequalities of the mountain slope, has either +two equal or three unequal sides. But if a shaft is inclined and is sunk +in one vein, and a tunnel is driven in another vein, then a triangle +comes into existence which has either an obtuse angle or all acute +angles. The former the Greeks call [Greek: amblygônion], the latter +[Greek: oxygônion]. That triangle which has an obtuse angle cannot have +three equal sides, but in accordance with the different mountain slopes +has either two equal sides or three unequal sides. That triangle which +has all acute angles in accordance with the different mountain slopes +has either three equal sides, which the Greeks call [Greek: trigônon +isopleuron] or two equal sides or three unequal sides. + +The surveyor, as I said, employs his art when the owners of the mines +desire to know how many fathoms of the intervening ground require to be +dug; when a tunnel is being driven toward a shaft and does not yet reach +it; or when the shaft has not yet been sunk to the depth of the bottom +of the tunnel which is under it; or when neither the tunnel reaches to +that point, nor has the shaft been sunk to it. It is of importance that +miners should know how many fathoms remain from the tunnel to the shaft, +or from the shaft to the tunnel, in order to calculate the expenditure; +and in order that the owners of a metal-bearing mine may hasten the +sinking of a shaft and the excavation of the metal, before the tunnel +reaches that point and the tunnel owners excavate part of the metal by +any right of their own; and on the other hand, it is important that the +owners of a tunnel may similarly hasten their driving before a shaft can +be sunk to the depth of a tunnel, so that they may excavate the metal to +which they will have a right. + +[Illustration 131 (Surveying): A--Upright forked posts. B--Pole over the +posts. C--Shaft. D--First cord. E--Weight of first cord. F--Second cord. +G--Same fixed ground. H--Head of first cord. I--Mouth of tunnel. +K--Third cord. L--Weight of third cord. M--First side minor triangle. +N--Second side minor triangle. O--Third side minor triangle. P--The +minor triangle.] + +The surveyor, first of all, if the beams of the shaft-house do not give +him the opportunity, sets a pair of forked posts by the sides of the +shaft in such a manner that a pole may be laid across them. Next, from +the pole he lets down into the shaft a cord with a weight attached to +it. Then he stretches a second cord, attached to the upper end of the +first cord, right down along the slope of the mountain to the bottom of +the mouth of the tunnel, and fixes it to the ground. Next, from the same +pole not far from the first cord, he lets down a third cord, similarly +weighted, so that it may intersect the second cord, which descends +obliquely. Then, starting from that point where the third cord cuts the +second cord which descends obliquely to the mouth of the tunnel, he +measures the second cord upward to where it reaches the end of the +first cord, and makes a note of this first side of the minor +triangle[17]. Afterward, starting again from that point where the third +cord intersects the second cord, he measures the straight space which +lies between that point and the opposite point on the first cord, and in +that way forms the minor triangle, and he notes this second side of the +minor triangle in the same way as before. Then, if it is necessary, from +the angle formed by the first cord and the second side of the minor +triangle, he measures upward to the end of the first cord and also makes +a note of this third side of the minor triangle. The third side of the +minor triangle, if the shaft is vertical or inclined and is sunk on the +same vein in which the tunnel is driven, will necessarily be the same +length as the third cord above the point where it intersects the second +cord; and so, as often as the first side of the minor triangle is +contained in the length of the whole cord which descends obliquely, so +many times the length of the second side of the minor triangle indicates +the distance between the mouth of the tunnel and the point to which the +shaft must be sunk; and similarly, so many times the length of the third +side of the minor triangle gives the distance between the mouth of the +shaft and the bottom of the tunnel. + +When there is a level bench on the mountain slope, the surveyor first +measures across this with a measuring-rod; then at the edges of this +bench he sets up forked posts, and applies the principle of the triangle +to the two sloping parts of the mountain; and to the fathoms which are +the length of that part of the tunnel determined by the triangles, he +adds the number of fathoms which are the width of the bench. But if +sometimes the mountain side stands up, so that a cord cannot run down +from the shaft to the mouth of the tunnel, or, on the other hand, cannot +run up from the mouth of the tunnel to the shaft, and, therefore, one +cannot connect them in a straight line, the surveyor, in order to fix an +accurate triangle, measures the mountain; and going downward he +substitutes for the first part of the cord a pole one fathom long, and +for the second part a pole half a fathom long. Going upward, on the +contrary, for the first part of the cord he substitutes a pole half a +fathom long, and for the next part, one a whole fathom long; then where +he requires to fix his triangle he adds a straight line to these angles. + +[Illustration 133 (Surveying Triangle): A triangle having a right angle +and two equal sides.] + +To make this system of measuring clear and more explicit, I will proceed +by describing each separate kind of triangle. When a shaft is vertical +or inclined, and is sunk in the same vein on which the tunnel is driven, +there is created, as I said, a triangle containing a right angle. Now if +the minor triangle has the two sides equal, which, in accordance with +the numbering used by surveyors, are the second and third sides, then +the second and third sides of the major triangle will be equal; and so +also the intervening distances will be equal which lie between the mouth +of the tunnel and the bottom of the shaft, and which lie between the +mouth of the shaft and the bottom of the tunnel. For example, if the +first side of the minor triangle is seven feet long and the second and +likewise the third sides are five feet, and the length shown by the +cord for the side of the major triangle is 101 times seven feet, that is +117 fathoms and five feet, then the intervening space, of course, +whether the whole of it has been already driven through or has yet to be +driven, will be one hundred times five feet, which makes eighty-three +fathoms and two feet. Anyone with this example of proportions will be +able to construct the major and minor triangles in the same way as I +have done, if there be the necessary upright posts and cross-beams. When +a shaft is vertical the triangle is absolutely upright; when it is +inclined and is sunk on the same vein in which the tunnel is driven, it +is inclined toward one side. Therefore, if a tunnel has been driven into +the mountain for sixty fathoms, there remains a space of ground to be +penetrated twenty-three fathoms and two feet long; for five feet of the +second side of the major triangle, which lies above the mouth of the +shaft and corresponds with the first side of the minor triangle, must +not be added. Therefore, if the shaft has been sunk in the middle of the +head meer, a tunnel sixty fathoms long will reach to the boundary of the +meer only when the tunnel has been extended a further two fathoms and +two feet; but if the shaft is located in the middle of an ordinary meer, +then the boundary will be reached when the tunnel has been driven a +further length of nine fathoms and two feet. Since a tunnel, for every +one hundred fathoms of length, rises in grade one fathom, or at all +events, ought to rise as it proceeds toward the shaft, one more fathom +must always be taken from the depth allowed to the shaft, and one added +to the length allowed to the tunnel. Proportionately, because a tunnel +fifty fathoms long is raised half a fathom, this amount must be taken +from the depth of the shaft and added to the length of the tunnel. In +the same way if a tunnel is one hundred or fifty fathoms shorter or +longer, the same proportion also must be taken from the depth of the one +and added to the length of the other. For this reason, in the case +mentioned above, half a fathom and a little more must be added to the +distance to be driven through, so that there remain twenty-three +fathoms, five feet, two palms, one and a half digits and a fifth of a +digit; that is, if even the minutest proportions are carried out; and +surveyors do not neglect these without good cause. Similarly, if the +shaft is seventy fathoms deep, in order that it may reach to the bottom +of the tunnel, it still must be sunk a further depth of thirteen fathoms +and two feet, or rather twelve fathoms and a half, one foot, two digits, +and four-fifths of half a digit. And in this instance five feet must be +deducted from the reckoning, because these five feet complete the third +side of the minor triangle, which is above the mouth of the shaft, and +from its depth there must be deducted half a fathom, two palms, one and +a half digits and the fifth part of half a digit. But if the tunnel has +been driven to a point where it is under the shaft, then to reach the +roof of the tunnel the shaft must still be sunk a depth of eleven +fathoms, two and a half feet, one palm, two digits, and four-fifths of +half a digit. + +[Illustration 134 (Surveying Triangle): A triangle having a right angle +and three unequal sides.] + +If a minor triangle is produced of the kind having three unequal sides, +then the sides of the greater triangle cannot be equal; that is, if the +first side of the minor triangle is eight feet long, the second six feet +long, and the third five feet long, and the cord along the side of the +greater triangle, not to go too far from the example just given, is one +hundred and one times eight feet, that is, one hundred and thirty-four +fathoms and four feet, the distance which lies between the mouth of the +tunnel and the bottom of the shaft will occupy one hundred times six +feet in length, that is, one hundred fathoms. The distance between the +mouth of the shaft and the bottom of the tunnel is one hundred times +five feet, that is, eighty-three fathoms and two feet. And so, if the +tunnel is eighty-five fathoms long, the remainder to be driven into the +mountain is fifteen fathoms long, and here, too, a correction in +measurement must be taken from the depth of the shaft and added to the +length of the tunnel; what this is precisely, I will pursue no further, +since everyone having a small knowledge of arithmetic can work it out. +If the shaft is sixty-seven fathoms deep, in order that it may reach the +bottom of the tunnel, the further distance required to be sunk amounts +to sixteen fathoms and two feet. + +[Illustration 135a (Surveying Triangle): Triangle having an obtuse angle +and two equal sides.] + +The surveyor employs this same method in measuring the mountain, whether +the shaft and tunnel are on one and the same vein, whether the vein is +vertical or inclined, or whether the shaft is on the principal vein and +the tunnel on a transverse vein descending vertically to the depths of +the earth; in the latter case the excavation is to be made where the +transverse vein cuts the vertical vein. If the principal vein descends +on an incline and the cross-vein descends vertically, then a minor +triangle is created having one obtuse angle or all three angles acute. +If the minor triangle has one angle obtuse and the two sides which are +the second and third are equal, then the second and third sides of the +major triangle will be equal, so that if the first side of the minor +triangle is nine feet, the second, and likewise the third, will be five +feet. Then the first side of the major triangle will be one hundred and +one times nine feet, or one hundred and fifty-one and one-half fathoms, +and each of the other sides of the major triangle will be one hundred +times five feet, that is, eighty-three fathoms and two feet. But when +the first shaft is inclined, generally speaking, it is not deep; but +there are usually several, all inclined, and one always following the +other. Therefore, if a tunnel is seventy-seven fathoms long, it will +reach to the middle of the bottom of a shaft when six fathoms and two +feet further have been sunk. But if all such inclined shafts are +seventy-six fathoms deep, in order that the last one may reach the +bottom of the tunnel, a depth of seven fathoms and two feet remains to +be sunk. + +[Illustration 135b (Surveying Triangle): Triangle having an obtuse angle +and three unequal sides.] + +If a minor triangle is made which has an obtuse angle and three unequal +sides, then again the sides of the large triangle cannot be equal. For +example, if the first side of the minor triangle is six feet long, the +second three feet, and the third four feet, and the cord along the side +of the greater triangle one hundred and one times six feet, that is, one +hundred and one fathoms, the distance between the mouth of the tunnel +and the bottom of the last shaft will be a length one hundred times +three feet, or fifty fathoms; but the depth that lies between the mouth +of the first shaft and the bottom of the tunnel is one hundred times +four feet, or sixty-six fathoms and four feet. Therefore, if a tunnel is +forty-four fathoms long, the remaining distance to be driven is six +fathoms. If the shafts are fifty-eight fathoms deep, the newest will +touch the bottom of the tunnel when eight fathoms and four feet have +been sunk. + +[Illustration 136a (Surveying Triangle): A triangle having all its +angles acute and its three sides equal.] + +If a minor triangle is produced which has all its angles acute and its +three sides equal, then necessarily the second and third sides of the +minor triangle will be equal, and likewise the sides of the major +triangle frequently referred to will be equal. Thus if each side of the +minor triangle is six feet long, and the cord measurement for the side +of the major triangle is one hundred and one times six feet, that is, +one hundred and one fathoms, then both the distances to be dug will be +one hundred fathoms. And thus if the tunnel is ninety fathoms long, it +will reach the middle of the bottom of the last shaft when ten fathoms +further have been driven. If the shafts are ninety-five fathoms deep, +the last will reach the bottom of the tunnel when it is sunk a further +depth of five fathoms. + +[Illustration 136b (Surveying Triangle): Triangle having all its angles +acute and two sides equal, A, B, unequal side C.] + +If a triangle is made which has all its angles acute, but only two sides +equal, namely, the first and third, then the second and third sides are +not equal; therefore the distances to be dug cannot be equal. For +example, if the first side of the minor triangle is six feet long, and +the second is four feet, and the third is six feet, and the cord +measurement for the side of the major triangle is one hundred and one +times six feet, that is, one hundred and one fathoms, then the distance +between the mouth of the tunnel and the bottom of the last shaft will be +sixty-six fathoms and four feet. But the distance from the mouth of the +first shaft to the bottom of the tunnel is one hundred fathoms. So if +the tunnel is sixty fathoms long, the remaining distance to be driven +into the mountain is six fathoms and four feet. If the shaft is +ninety-seven fathoms deep, the last one will reach the bottom of the +tunnel when a further depth of three fathoms has been sunk. + +[Illustration 137 (Surveying Triangle): A triangle having all its angles +acute and its three sides unequal.] + +If a minor triangle is produced which has all its angles acute, but its +three sides unequal, then again the distances to be dug cannot be equal. +For example, if the first side of the minor triangle is seven feet long, +the second side is four feet, and the third side is six feet, and the +cord measurement for the side of the major triangle is one hundred and +one times seven feet or one hundred and seventeen fathoms and four feet, +the distance between the mouth of the tunnel and the bottom of the last +shaft will be four hundred feet or sixty-six fathoms, and the depth +between the mouth of the first shaft and the bottom of the tunnel will +be one hundred fathoms. Therefore, if a tunnel is fifty fathoms long, it +will reach the middle of the bottom of the newest shaft when it has been +driven sixteen fathoms and four feet further. But if the shafts are then +ninety-two fathoms deep, the last shaft will reach the bottom of the +tunnel when it has been sunk a further eight fathoms. + +This is the method of the surveyor in measuring the mountain, if the +principal vein descends inclined into the depths of the earth or the +transverse vein is vertical. But if they are both inclined, the surveyor +uses the same method, or he measures the slope of the mountain +separately from the slope of the shaft. Next, if a transverse vein in +which a tunnel is driven does not cut the principal vein in that spot +where the shaft is sunk, then it is necessary for the starting point of +the survey to be in the other shaft in which the transverse vein cuts +the principal vein. But if there be no shaft on that spot where the +outcrop of the transverse vein cuts the outcrop of the principal vein, +then the surface of the ground which lies between the shafts must be +measured, or that between the shaft and the place where the outcrop of +the one vein intersects the outcrop of the other. + +[Illustration 138 (Hemicycle): A--Waxed semicircle of the hemicycle. +B--Semicircular lines. C--Straight lines. D--Line measuring the half. +E--Line measuring the whole. F--Tongue.] + +[Illustration 138A (Surveying Rods): A--Lines of the rod which separate +minor spaces. B--Lines of the rod which separate major spaces.] + +Some surveyors, although they use three cords, nevertheless ascertain +only the length of a tunnel by that method of measuring, and determine +the depth of a shaft by another method; that is, by the method by which +cords are re-stretched on a level part of the mountain or in a valley, +or in flat fields, and are measured again. Some, however, do not employ +this method in surveying the depth of a shaft and the length of a +tunnel, but use only two cords, a graduated hemicycle[18] and a rod half +a fathom long. They suspend in the shaft one cord, fastened from the +upper pole and weighted, just as the others do. Fastened to the upper +end of this cord, they stretch another right down the slope of the +mountain to the bottom of the mouth of the tunnel and fix it to the +ground. Then to the upper part of this second cord they apply on its +lower side the broad part of a hemicycle. This consists of half a +circle, the outer margin of which is covered with wax, and within this +are six semi-circular lines. From the waxed margin through the first +semi-circular line, and reaching to the second, there proceed straight +lines converging toward the centre of the hemicycle; these mark the +middles of intervening spaces lying between other straight lines which +extend to the fourth semi-circular line. But all lines whatsoever, from +the waxed margin up to the fourth line, whether they go beyond it or +not, correspond with the graduated lines which mark the minor spaces of +a rod. Those which go beyond the fourth line correspond with the lines +marking the major spaces on the rod, and those which proceed further, +mark the middle of the intervening space which lies between the others. +The straight lines, which run from the fifth to the sixth semi-circular +line, show nothing further. Nor does the line which measures the half, +show anything when it has already passed from the sixth straight line to +the base of the hemicycle. When the hemicycle is applied to the cord, if +its tongue indicates the sixth straight line which lies between the +second and third semi-circular lines, the surveyor counts on the rod six +lines which separate the minor spaces, and if the length of this portion +of the rod be taken from the second cord, as many times as the cord +itself is half-fathoms long, the remaining length of cord shows the +distance the tunnel must be driven to reach under the shaft. But if he +sees that the tongue has gone so far that it marks the sixth line +between the fourth and fifth semi-circular lines, he counts six lines +which separate the major spaces on the rod; and this entire space is +deducted from the length of the second cord, as many times as the number +of whole fathoms which the cord contains; and then, in like manner, the +remaining length of cord shows us the distance the tunnel must be driven +to reach under the shaft.[19] + +[Illustration 139 (Surveying Triangle): Stretched cords: A--First cord. +B--Second cord. C--Third cord. D--Triangle.] + +Both these surveyors, as well as the others, in the first place make +use of the haulage rope. These they measure by means of others made of +linden bark, because the latter do not stretch at all, while the former +become very slack. These cords they stretch on the surveyor's field, the +first one to represent the parts of mountain slopes which descend +obliquely. Then the second cord, which represents the length of the +tunnel to be driven to reach the shaft, they place straight, in such a +direction that one end of it can touch the lower end of the first cord; +then they similarly lay the third cord straight, and in such a direction +that its upper end may touch the upper end of the first cord, and its +lower end the other extremity of the second cord, and thus a triangle is +formed. This third cord is measured by the instrument with the index, to +determine its relation to the perpendicular; and the length of this cord +shows the depth of the shaft. + +[Illustration 140 (Surveying Triangles): Stretched cords: A--First. +B--Second. B--Third. C--Fourth. C--Fifth. D--Quadrangle.] + +Some surveyors, to make their system of measuring the depth of a shaft +more certain, use five stretched cords: the first one descending +obliquely; two, that is to say the second and third, for ascertaining +the length of the tunnel; two for the depth of the shaft; in which way +they form a quadrangle divided into two equal triangles, and this tends +to greater accuracy. + +These systems of measuring the depth of a shaft and the length of a +tunnel, are accurate when the vein and also the shaft or shafts go down +to the tunnel vertically or inclined, in an uninterrupted course. The +same is true when a tunnel runs straight on to a shaft. But when each of +them bends now in this, now in that direction, if they have not been +completely driven and sunk, no living man is clever enough to judge how +far they are deflected from a straight course. But if the whole of +either one of the two has been excavated its full distance, then we can +estimate more easily the length of one, or the depth of the other; and +so the location of the tunnel, which is below a newly-started shaft, is +determined by a method of surveying which I will describe. First of all +a tripod is fixed at the mouth of the tunnel, and likewise at the mouth +of the shaft which has been started, or at the place where the shaft +will be started. The tripod is made of three stakes fixed to the ground, +a small rectangular board being placed upon the stakes and fixed to +them, and on this is set a compass. Then from the lower tripod a +weighted cord is let down perpendicularly to the earth, close to which +cord a stake is fixed in the ground. To this stake another cord is tied +and drawn straight into the tunnel to a point as far as it can go +without being bent by the hangingwall or the footwall of the vein. Next, +from the cord which hangs from the lower tripod, a third cord likewise +fixed is brought straight up the sloping side of the mountain to the +stake of the upper tripod, and fastened to it. In order that the +measuring of the depth of the shaft may be more certain, the third cord +should touch one and the same side of the cord hanging from the lower +tripod which is touched by the second cord--the one which is drawn into +the tunnel. All this having been correctly carried out, the surveyor, +when at length the cord which has been drawn straight into the tunnel is +about to be bent by the hangingwall or footwall, places a plank in the +bottom of the tunnel and on it sets the orbis, an instrument which has +an indicator peculiar to itself. This instrument, although it also has +waxed circles, differs from the other, which I have described in the +third book. But by both these instruments, as well as by a rule and a +square, he determines whether the stretched cords reach straight to the +extreme end of the tunnel, or whether they sometimes reach straight, and +are sometimes bent by the footwall or hangingwall. Each instrument is +divided into parts, but the compass into twenty-four parts, the orbis +into sixteen parts; for first of all it is divided into four principal +parts, and then each of these is again divided into four. Both have +waxed circles, but the compass has seven circles, and the orbis only +five circles. These waxed circles the surveyor marks, whichever +instrument he uses, and by the succession of these same marks he notes +any change in the direction in which the cord extends. The orbis has an +opening running from its outer edge as far as the centre, into which +opening he puts an iron screw, to which he binds the second cord, and by +screwing it into the plank, fixes it so that the orbis may be immovable. +He takes care to prevent the second cord, and afterward the others which +are put up, from being pulled off the screw, by employing a heavy iron, +into an opening of which he fixes the head of the screw. In the case of +the compass, since it has no opening, he merely places it by the side of +the screw. That the instrument does not incline forward or backward, and +in that way the measurement become a greater length than it should be, +he sets upon the instrument a standing plummet level, the tongue of +which, if the instrument is level, indicates no numbers, but the point +from which the numbers start. + +[Illustration 142 (Compass): Compass. A, B, C, D, E, F, G are the seven +waxed circles.] + +[Illustration 142A (Orbis): A, B, C, D, E--Five waxed circles of the +_orbis_. F--Opening of same. G--Screw. H--Perforated iron.] + +[Illustration 143 (Miner using level): A--Standing plummet level. +B--Tongue. C--Level and tongue.] + +When the surveyor has carefully observed each separate angle of the +tunnel and has measured such parts as he ought to measure, then he lays +them out in the same way on the surveyor's field[20] in the open air, +and again no less carefully observes each separate angle and measures +them. First of all, to each angle, according as the calculation of his +triangle and his art require it, he lays out a straight cord as a line. +Then he stretches a cord at such an angle as represents the slope of +the mountain, so that its lower end may reach the end of the straight +cord; then he stretches a third cord similarly straight and at such an +angle, that with its upper end it may reach the upper end of the second +cord, and with its lower end the last end of the first cord. The length +of the third cord shows the depth of the shaft, as I said before, and at +the same time that point on the tunnel to which the shaft will reach +when it has been sunk. + +If one or more shafts reach the tunnel through intermediate drifts and +shafts, the surveyor, starting from the nearest which is open to the +air, measures in a shorter time the depth of the shaft which requires to +be sunk, than if he starts from the mouth of the tunnel. First of all he +measures that space on the surface which lies between the shaft which +has been sunk and the one which requires to be sunk. Then he measures +the incline of all the shafts which it is necessary to measure, and the +length of all the drifts with which they are in any way connected to the +tunnel. Lastly, he measures part of the tunnel; and when all this is +properly done, he demonstrates the depth of the shaft and the point in +the tunnel to which the shaft will reach. But sometimes a very deep +straight shaft requires to be sunk at the same place where there is a +previous inclined shaft, and to the same depth, in order that loads may +be raised and drawn straight up by machines. Those machines on the +surface are turned by horses; those inside the earth, by the same means, +and also by water-power. And so, if it becomes necessary to sink such a +shaft, the surveyor first of all fixes an iron screw in the upper part +of the old shaft, and from the screw he lets down a cord as far as the +first angle, where again he fixes a screw, and again lets down the cord +as far as the second angle; this he repeats again and again until the +cord reaches to the bottom of the shaft. Then to each angle of the cord +he applies a hemicycle, and marks the waxed semi-circle according to the +lines which the tongue indicates, and designates it by a number, in case +it should be moved; then he measures the separate parts of the cord with +another cord made of linden bark. Afterward, when he has come back out +of the shaft, he goes away and transfers the markings from the waxed +semi-circle of the hemicycle to an orbis similarly waxed. Lastly, the +cords are stretched on the surveyor's field, and he measures the angles, +as the system of measuring by triangles requires, and ascertains which +part of the footwall and which part of the hangingwall rock must be cut +away in order that the shaft may descend straight. But if the surveyor +is required to show the owners of the mine, the spot in a drift or a +tunnel in which a shaft needs to be raised from the bottom upward, that +it should cut through more quickly, he begins measuring from the bottom +of the drift or tunnel, at a point beyond the spot at which the bottom +of the shaft will arrive, when it has been sunk. When he has measured +the part of the drift or tunnel up to the first shaft which connects +with an upper drift, he measures the incline of this shaft by applying a +hemicycle or orbis to the cord. Then in a like manner he measures the +upper drift and the incline shaft which is sunk therein toward which a +raise is being dug, then again all the cords are stretched in the +surveyor's field, the last cord in such a way that it reaches the first, +and then he measures them. From this measurement is known in what part +of the drift or tunnel the raise should be made, and how many fathoms +of vein remain to be broken through in order that the shaft may be +connected. + +I have described the first reason for surveying; I will now describe +another. When one vein comes near another, and their owners are +different persons who have late come into possession, whether they drive +a tunnel or a drift, or sink a shaft, they may encroach, or seem to +encroach, without any lawful right, upon the boundaries of the older +owners, for which reason the latter very often seek redress, or take +legal proceedings. The surveyor either himself settles the dispute +between the owners, or by his art gives evidence to the judges for +making their decision, that one shall not encroach on the mine of the +other. Thus, first of all he measures the mines of each party with a +basket rope and cords of linden bark; and having applied to the cords an +orbis or a compass, he notes the directions in which they extend. Then +he stretches the cords on the surveyor's field; and starting from that +point whose owners are in possession of the old meer toward the other, +whether it is in the hanging or footwall of the vein, he stretches a +cross-cord in a straight line, according to the sixth division of the +compass, that is, at a right angle to the vein, for a distance of three +and a half fathoms, and assigns to the older owners that which belongs +to them. But if both ends of one vein are being dug out in two tunnels, +or drifts from opposite directions, the surveyor first of all considers +the lower tunnel or drift and afterward the upper one, and judges how +much each of them has risen little by little. On each side strong men +take in their hands a stretched cord and hold it so that there is no +point where it is not strained tight; on each side the surveyor supports +the cord with a rod half a fathom long, and stays the rod at the end +with a short stick as often as he thinks it necessary. But some fasten +cords to the rods to make them steadier. The surveyor attaches a +suspended plummet level to the middle of the cord to enable him to +calculate more accurately on both sides, and from this he ascertains +whether one tunnel has risen more than another, or in like manner one +drift more than another. Afterward he measures the incline of the shafts +on both sides, so that he can estimate their position on each side. Then +he easily sees how many fathoms remain in the space which must be broken +through. But the grade of each tunnel, as I said, should rise one fathom +in the distance of one hundred fathoms. + +[Illustration 146 (Plummet cord and weight): Indicator of a suspended +plummet level.] + +[Illustration 147 (Compass): A--Needle of the instrument. B--Its tongue. +C, D, E--Holes in the tongue.] + +The Swiss surveyors, when they wish to measure tunnels driven into the +highest mountains, also use a rod half a fathom long, but composed of +three parts, which screw together, so that they may be shortened. They +use a cord made of linden bark to which are fastened slips of paper +showing the number of fathoms. They also employ an instrument peculiar +to them, which has a needle; but in place of the waxed circles they +carry in their hands a chart on which they inscribe the readings of the +instrument. The instrument is placed on the back part of the rod so that +the tongue, and the extended cord which runs through the three holes in +the tongue, demonstrates the direction, and they note the number of +fathoms. The tongue shows whether the cord inclines forward or backward. +The tongue does not hang, as in the case of the suspended plummet +level, but is fixed to the instrument in a half-lying position. They +measure the tunnels for the purpose of knowing how many fathoms they +have been increased in elevation; how many fathoms the lower is distant +from the upper one; how many fathoms of interval is not yet pierced +between the miners who on opposite sides are digging on the same vein, +or cross-stringers, or two veins which are approaching one another. + +But I return to our mines. If the surveyor desires to fix the boundaries +of the meer within the tunnels or drifts, and mark to them with a sign +cut in the rock, in the same way that the _Bergmeister_ has marked these +boundaries above ground, he first of all ascertains, by measuring in the +manner which I have explained above, which part of the tunnel or drift +lies beneath the surface boundary mark, stretching the cords along the +drifts to a point beyond that spot in the rock where he judges the mark +should be cut. Then, after the same cords have been laid out on the +surveyor's field, he starts from that upper cord at a point which shows +the boundary mark, and stretches another cross-cord straight downward +according to the sixth division of the compass--that is at a right +angle. Then that part of the lowest cord which lies beyond the part to +which the cross-cord runs being removed, it shows at what point the +boundary mark should be cut into the rock of the tunnel or drift. The +cutting is made in the presence of the two Jurors and the manager and +the foreman of each mine. For as the _Bergmeister_ in the presence of +these same persons sets the boundary stones on the surface, so the +surveyor cuts in the rock a sign which for this reason is called the +boundary rock. If he fixes the boundary mark of a meer in which a shaft +has recently begun to be sunk on a vein, first of all he measures and +notes the incline of that shaft by the compass or by another way with +the applied cords; then he measures all the drifts up to that one in +whose rock the boundary mark has to be cut. Of these drifts he measures +each angle; then the cords, being laid out on the surveyor's field, in a +similar way he stretches a cross-cord, as I said, and cuts the sign on +the rock. But if the underground boundary rock has to be cut in a drift +which lies beneath the first drift, the surveyor starts from the mark in +the first drift, notes the different angles, one by one, takes his +measurements, and in the lower drift stretches a cord beyond that place +where he judges the mark ought to be cut; and then, as I said before, +lays out the cords on the surveyor's field. Even if a vein runs +differently in the lower drift from the upper one, in which the first +boundary mark has been cut in the rock, still, in the lower drift the +mark must be cut in the rock vertically beneath. For if he cuts the +lower mark obliquely from the upper one some part of the possession of +one mine is taken away to its detriment, and given to the other. +Moreover, if it happens that the underground boundary mark requires to +be cut in an angle, the surveyor, starting from that angle, measures one +fathom toward the front of the mine and another fathom toward the back, +and from these measurements forms a triangle, and dividing its middle by +a cross-cord, makes his cutting for the boundary mark. + +Lastly, the surveyor sometimes, in order to make more certain, finds the +boundary of the meers in those places where many old boundary marks are +cut in the rock. Then, starting from a stake fixed on the surface, he +first of all measures to the nearest mine; then he measures one shaft +after another; then he fixes a stake on the surveyors' field, and making +a beginning from it stretches the same cords in the same way and +measures them, and again fixes in the ground a stake which for him will +signify the end of his measuring. Afterward he again measures +underground from that spot at which he left off, as many shafts and +drifts as he can remember. Then he returns to the surveyor's field, and +starting again from the second stake, makes his measurements; and he +does this as far as the drift in which the boundary mark must be cut in +the rock. Finally, commencing from the stake first fixed in the ground, +he stretches a cross-cord in a straight line to the last stake, and this +shows the length of the lowest drift. The point where they touch, he +judges to be the place where the underground boundary mark should be +cut. + + END OF BOOK V. + + +FOOTNOTES: + +[1] It has been suggested that we should adopt throughout this volume +the mechanical and mining terms used in English mines at Agricola's +time. We believe, however, that but a little inquiry would illustrate +the undesirability of this course as a whole. Where there is choice in +modern miner's nomenclature between an old and a modern term, we have +leaned toward age, if it be a term generally understood. But except +where the subject described has itself become obsolete, we have revived +no obsolete terms. In substantiation of this view, we append a few +examples of terms which served the English miner well for centuries, +some of which are still extant in some local communities, yet we believe +they would carry as little meaning to the average reader as would the +reproduction of the Latin terms coined by Agricola. + + Rake = A perpendicular vein. + Woughs = Walls of the vein. + Shakes = Cracks in the walls. + Flookan = Gouge. + Bryle = Outcrop. + Hade = Incline or underlay of the vein. + Dawling = Impoverishment of the vein. + Rither = A "horse" in a vein. + Twitches = "Pinching" of a vein. + Slough = Drainage tunnel. + Sole = Lowest drift. + Stool = Face of a drift or stope. + Winds } + Turn } = Winze. + Dippas} + Grove = Shaft. + Dutins = Set of timber. + Stemple = Post or stull. + Laths = Lagging. + +As examples of the author's coinage and adaptations of terms in this +book we may cite:-- + + _Fossa latens_ = Drift. + _Fossa latens transversa_ = Crosscut. + _Tectum_ = Hangingwall. + _Fundamentum_ = Footwall. + _Tigna per intervalla posita_ = Wall plate. + _Arbores dissectae_ = Lagging. + _Formae_ = Hitches. + +We have adopted the term "tunnel" for openings by way of outlet to the +mine. The word in this narrow sense is as old as "adit," a term less +expressive and not so generally used in the English-speaking mining +world. We have for the same reason adopted the word "drift" instead of +the term "level" so generally used in America, because that term always +leads to confusion in discussion of mine surveys. We may mention, +however, that the term "level" is a heritage from the Derbyshire mines, +and is of an equally respectable age as "drift." + +[2] See note on p. 46-47. The _canales_, as here used, were the openings +in the earth, in which minerals were deposited. + +[3] This statement, as will appear by the description later on, refers +to the depth of winzes or to the distance between drifts, that is "the +lift." We have not, however, been justified in using the term "winze," +because some of these were openings to the surface. As showing the +considerable depth of shafts in Agricola's time, we may quote the +following from _Bermannus_ (p. 442): "The depths of our shafts forced us +to invent hauling machines suitable for them. There are some of them +larger and more ingenious than this one, for use in deep shafts, as, for +instance, those in my native town of Geyer, but more especially at +Schneeberg, where the shaft of the mine from which so much treasure was +taken in our memory has reached the depth of about 200 fathoms (feet?), +wherefore the necessity of this kind of machinery. _Naevius_: What an +enormous depth! Have you reached the Inferno? _Bermannus_: Oh, at +Kuttenberg there are shafts more than 500 fathoms (feet?) deep. +_Naevius_: And not yet reached the Kingdom of Pluto?" It is impossible +to accept these as fathoms, as this would in the last case represent +3,000 feet vertically. The expression used, however, for fathoms is +_passus_, presumably the Roman measure equal to 58.1 inches. + +[4] _Cavernos_. The Glossary gives _drusen_, our word _drusy_ having had +this origin. + +[5] _Purum_,--"pure." _Interpretatio_ gives the German as +_gedigen_,--"native." + +[6] _Rudis_,--"Crude." By this expression the author really means ores +very rich in any designated metal. In many cases it serves to indicate +the minerals of a given metal, as distinguished from the metal itself. +Our system of mineralogy obviously does not afford an acceptable +equivalent. Agricola (_De Nat. Foss._, p. 360) says: "I find it +necessary to call each genus (of the metallic minerals) by the name of +its own metal, and to this I add a word which differentiates it from the +pure (_puro_) metal, whether the latter has been mined or smelted; so I +speak of _rudis_ gold, silver, quicksilver, copper, tin, bismuth, lead, +or iron. This is not because I am unaware that Varro called silver +_rudis_ which had not yet been refined and stamped, but because a word +which will distinguish the one from the other is not to be found." + +[7] The reasons for retaining the Latin weights are given in the +Appendix on Weights and Measures. A _centumpondium_ weighs 70.6 lbs. +avoirdupois, an _uncia_ 412.2 Troy grains, therefore, this value is +equal to 72 ounces 18 pennyweights per short ton. + +[8] Agricola mentions many minerals in _De Re Metallica_, but without +such description as would make possible a hazard at their identity. From +his _De Natura Fossilium_, however, and from other mineralogies of the +16th Century, some can be fully identified and others surmised. While we +consider it desirable to set out the probable composition of these +minerals, on account of the space required, the reasons upon which our +opinion has been based cannot be given in detail, as that would require +extensive quotations. In a general way, we have throughout the text +studiously evaded the use of modern mineralogical terms--unless the term +used to-day is of Agricola's age--and have adopted either old English +terms of pre-chemistry times or more loose terms used by common miners. +Obviously modern mineralogic terms imply a precision of knowledge not +existing at that period. It must not be assumed that the following is by +any means a complete list of the minerals described by Agricola, but +they include most of those referred to in this chapter. His system of +mineralogy we have set out in note 4, p. 1, and it requires no further +comment here. The grouping given below is simply for convenience and +does not follow Agricola's method. Where possible, we tabulate in +columns the Latin term used in _De Re Metallica_; the German equivalent +given by the Author in either the _Interpretatio_ or the Glossary; our +view of the probable modern equivalent based on investigation of his +other works and other ancient mineralogies, and lastly the terms we have +adopted in the text. The German spelling is that given in the original. +As an indication of Agricola's position as a mineralogist, we mark with +an asterisk the minerals which were first specifically described by him. +We also give some notes on matters of importance bearing on the +nomenclature used in _De Re Metallica_. Historical notes on the chief +metals will be found elsewhere, generally with the discussion of +smelting methods. We should not omit to express our indebtedness to +Dana's great "System of Mineralogy," in the matter of correlation of +many old and modern minerals. + +GOLD MINERALS. Agricola apparently believed that there were various gold +minerals, green, yellow, purple, black, etc. There is nothing, however, +in his works that permits of any attempt to identify them, and his +classification seems to rest on gangue colours. + +SILVER MINERALS. + + _Argentum purum in _Gedigen silber_ -- *Native silver + venis reperitur_ + + _Argentum rude_ _Gedigen silber -- _Rudis_ silver, or + ertz_ pure silver + minerals + + _Argentum rude _Glas ertz_ Argentite *Silver glance + plumbei coloris_ (Ag_{2}S) + + _Argentum rude _Rot gold ertz_ Pyrargyrite *Red silver + rubrum_ (Ag_{3}SbS_{3}) + + _Argentum rude _Durchsichtig Proustite *Ruby silver + rubrum rod gulden (Ag_{3}AsS_{3}) + translucidum_ ertz_ + + _Argentum rude _Weis rod gulden -- White silver + album_ ertz: Dan es + ist frisch wie + offtmals rod + gulden ertz + pfleget zusein_ + + _Argentum rude _Gedigen Part Bromyrite Liver-coloured + jecoris leberfarbig (Ag Br) silver + colore_ ertz_ + + _Argentum rude _Gedigen -- Yellow silver + luteum_ geelertz_ + + _Argentum rude _Gedigen graw } { *Grey silver + cineraceum_ ertz_ } Part Cerargurite { + } (Ag Cl) (Horn { + _Argentum rude _Gedigen } Silver) Part { *Black silver + nigrum_ schwartz ertz_ } Stephanite { + } (Ag_{5}SbS_{4}) { + _Argentum rude _Gedigen braun } { *Purple silver + purpureum_ ertz_ } { + +The last six may be in part also alteration products from all silver +minerals. + +The reasons for indefiniteness in determination usually lie in the +failure of ancient authors to give sufficient or characteristic +descriptions. In many cases Agricola is sufficiently definite as to +assure certainty, as the following description of what we consider to be +silver glance, from _De Natura Fossilium_ (p. 360), will indicate: +"Lead-coloured _rudis_ silver is called by the Germans from the word +glass (_glasertz_), not from lead. Indeed, it has the colour of the +latter or of galena (_plumbago_), but not of glass, nor is it +transparent like glass, which one might indeed expect had the name been +correctly derived. This mineral is occasionally so like galena in +colour, although it is darker, that one who is not experienced in +minerals is unable to distinguish between the two at sight, but in +substance they differ greatly from one another. Nature has made this +kind of silver out of a little earth and much silver. Whereas galena +consists of stone and lead containing some silver. But the distinction +between them can be easily determined, for galena may be ground to +powder in a mortar with a pestle, but this treatment flattens out this +kind of _rudis_ silver. Also galena, when struck by a mallet or bitten +or hacked with a knife, splits and breaks to pieces; whereas this silver +is malleable under the hammer, may be dented by the teeth, and cut with +a knife." + +COPPER MINERALS. + + _Aes purum _Gedigen kupfer_ Native copper Native copper + fossile_ + + _Aes rude _Kupferglas ertz_ Chalcocite *Copper glance + plumbei (Cu_{2}S) + coloris_ + + _Chalcitis_ _Rodt atrament_ A decomposed _Chalcitis_ (see + copper or notes on p. 573) + iron sulphide + + _Pyrites aurei } _Geelkis oder { Part chalcopyrite Copper pyrites + colore_ } kupferkis_ { (Cu Fe S) part + } { bornite + _Pyrites aerosus_ } { (Cu_{3}FeS_{3}) + + _Caeruleum_ _Berglasur_ Azurite Azure + + _Chrysocolla_ _Berggrün und { Part chrysocolla Chrysocolla (see + schifergrün_ { Part Malachite note 7, p. 560) + + _Molochites_ _Molochit_ Malachite Malachite + + _Lapis aerarius_ _Kupfer ertz_ -- Copper ore + + _Aes caldarium } _Lebeter kupfer_ { When used for + rubrum fuscum_ } { an ore, is *Ruby copper ore + or } { probably + _Aes sui coloris_ } _Rotkupfer_ { cuprite + + _Aes nigrum_ _Schwartz kupfer_ Probably CuO from *Black copper + oxidation of + other minerals + +In addition to the above the Author uses the following, which were in +the main artificial products: + + _Aerugo_ _Grünspan oder Verdigris Verdigris + Spanschgrün_ + + _Aes luteum_ _Gelfarkupfer_ } Impure blister { Unrefined copper + } copper { (see note 16, + } { p. 511) + _Aes caldarium_ _Lebeterkupfer_ } { + + _Aeris flos_ _Kupferbraun_ } Cupric oxide { Copper flower + } scales { + } { + _Aeris squama_ _Kupferhammer- } { Copper scale (see + schlag_ } { note 9, p. 233) + + _Atramentum _Blaw kupfer Chalcanthite Native blue + sutorium wasser_ vitriol (see + caeruleum_ or note on p. 572) + _chalcanthum_ + +Blue and green copper minerals were distinguished by all the ancient +mineralogists. Theophrastus, Dioscorides, Pliny, etc., all give +sufficient detail to identify their _cyanus_ and _caeruleum_ partly with +modern azurite, and their _chrysocolla_ partly with the modern mineral +of the same name. However, these terms were also used for vegetable +pigments, as well as for the pigments made from the minerals. The Greek +origin of _chrysocolla_ (_chrysos_, gold and _kolla_, solder) may be +blamed with another and distinct line of confusion, in that this term +has been applied to soldering materials, from Greek down to modern +times, some of the ancient mineralogists even asserting that the copper +mineral _chrysocolla_ was used for this purpose. Agricola uses +_chrysocolla_ for borax, but is careful to state in every case (see note +xx., p. x): "_Chrysocolla_ made from _nitrum_," or "_Chrysocolla_ which +the Moors call Borax." Dioscorides and Pliny mention substances which +were evidently copper sulphides, but no description occurs prior to +Agricola that permits a hazard as to different species. + +LEAD MINERALS. + + _Plumbarius lapis_ _Glantz_ Galena Galena + + _Galena_ _Glantz und Galena Galena + pleiertz_ + + _Plumbum nigrum } _Pleiertz oder Cerussite Yellow lead ore + lutei coloris_ } pleischweis_ (PbCO_{3}) + } + _Plumbago } + metallica_ } + + _Cerussa_ _Pleiweis_ Artificial White-lead (see + White-lead note 4, p. 440) + + _Ochra facticia_ _Pleigeel_ Massicot (Pb O) *Lead-ochre (see + or _ochra note 8, p. 232) + plumbaria_ + + _Molybdaena_ } _Herdplei_ Part litharge Hearth-lead (see + } note 37, p. 476) + _Plumbago } + fornacis_ } + + _Spuma argenti_ } _Glett_ Litharge Litharge (see note + } on p. 465) + _Lithargyrum_ } + + _Minium _Menning_ Minium Red-lead (see note + secundarium_ (Pb_{3}O_{4}) 7, p. 232) + +So far as we can determine, all of these except the first three were +believed by Agricola to be artificial products. Of the first three, +galena is certain enough, but while he obviously was familiar with the +alteration lead products, his descriptions are inadequate and much +confused with the artificial oxides. Great confusion arises in the +ancient mineralogies over the terms _molybdaena_, _plumbago_, _plumbum_, +_galena_, and _spuma argenti_, all of which, from Roman mineralogists +down to a century after Agricola, were used for lead in some form. +Further discussion of such confusion will be found in note 37, p. 476. +Agricola in _Bermannus_ and _De Natura Fossilium_, devotes pages to +endeavouring to reconcile the ancient usages of these terms, and all the +confusion existing in Agricola's time was thrice confounded when the +names _molybdaena_ and _plumbago_ were assigned to non-lead minerals. + +TIN. Agricola knew only one tin mineral: _Lapilli nigri ex quibus +conflatur plumbum candidum_, _i.e._, "Little black stones from which tin +is smelted," and he gives the German equivalent as _zwitter_, +"tin-stone." He describes them as being of different colours, but +probably due to external causes. + +ANTIMONY. (_Interpretatio_,--_spiesglas_.) The _stibi_ or _stibium_ of +Agricola was no doubt the sulphide, and he follows Dioscorides in +dividing it into male and female species. This distinction, however, is +impossible to apply from the inadequate descriptions given. The mineral +and metal known to Agricola and his predecessors was almost always the +sulphide, and we have not felt justified in using the term antimony +alone, as that implies the refined product, therefore, we have adopted +either the Latin term or the old English term "grey antimony." The +smelted antimony of commerce sold under the latter term was the +sulphide. For further notes see p. 428. + +BISMUTH*. _Plumbum cinereum_ (_Interpretatio_,--_bismut_). Agricola +states that this mineral occasionally occurs native, "but more often as +a mineral of another colour" (_De Nat. Fos._, p. 337), and he also +describes its commonest form as black or grey. This, considering his +localities, would indicate the sulphide, although he assigns no special +name to it. Although bismuth is mentioned before Agricola in the +_Nützliche Bergbüchlin_, he was the first to describe it (see p. 433). + +QUICKSILVER. Apart from native quicksilver, Agricola adequately +describes cinnabar only. The term used by him for the mineral is _minium +nativum_ (_Interpretatio_,--_bergzinober_ or _cinnabaris_). He makes the +curious statement _(De Nat. Fos._ p. 335) that _rudis_ quicksilver also +occurs liver-coloured and blackish,--probably gangue colours. (See p. +432). + +ARSENICAL MINERALS. Metallic arsenic was unknown, although it has been +maintained that a substance mentioned by Albertus Magnus (_De Rebus +Metallicis_) was the metallic form. Agricola, who was familiar with all +Albertus's writings, makes no mention of it, and it appears to us that +the statement of Albertus referred only to the oxide from sublimation. +Our word "arsenic" obviously takes root in the Greek for orpiment, which +was also used by Pliny (XXXIV, 56) as _arrhenicum_, and later was +modified to _arsenicum_ by the Alchemists, who applied it to the oxide. +Agricola gives the following in _Bermannus_ (p. 448), who has been +previously discussing realgar and orpiment:--"_Ancon_: Avicenna also has +a white variety. _Bermannus_: I cannot at all believe in a mineral of a +white colour; perhaps he was thinking of an artificial product; there +are two which the Alchemists make, one yellow and the other white, and +they are accounted the most powerful poisons to-day, and are called only +by the name _arsenicum_." In _De Natura Fossilium_ (p. 219) is described +the making of "the white variety" by sublimating orpiment, and also it +is noted that realgar can be made from orpiment by heating the latter +for five hours in a sealed crucible. In _De Re Metallica_ (Book X.), he +refers to _auripigmentum facticum_, and no doubt means the realgar made +from orpiment. The four minerals of arsenic base mentioned by Agricola +were:-- + + _Auripigmentum_ _Operment_ Orpiment Orpiment + (As_{2}S_{3}) + + _Sandaraca_ _Rosgeel_ Realgar (As S) Realgar + + _Arsenicum_ _Arsenik_ Artificial White arsenic + arsenical oxide + + _Lapis subrutilus _Mistpuckel_ Arsenopyrite *Mispickel + atque ... (Fe As S) + splendens_ + +We are somewhat uncertain as to the identification of the last. The +yellow and red sulphides, however, were well known to the Ancients, and +are described by Aristotle, Theophrastus (71 and 89), Dioscorides (V, +81), Pliny (XXXIII, 22, etc.); and Strabo (XII, 3, 40) mentions a mine +of them near Pompeiopolis, where, because of its poisonous character +none but slaves were employed. The Ancients believed that the yellow +sulphide contained gold--hence the name _auripigmentum_, and Pliny +describes the attempt of the Emperor Caligula to extract the gold from +it, and states that he did obtain a small amount, but unprofitably. So +late a mineralogist as Hill (1750) held this view, which seemed to be +general. Both realgar and orpiment were important for pigments, +medicinal purposes, and poisons among the Ancients. In addition to the +above, some arsenic-cobalt minerals are included under _cadmia_. + +IRON MINERALS. + + _Ferrum purum_ _Gedigen eisen_ Native iron *Native iron + + _Terra ferria_ _Eisen ertz_ } Various soft and } Ironstone + } hard iron } + _Ferri vena_ _Eisen ertz_ } ores, probably } + } mostly hematite} + _Galenae genus _Eisen glantz_ } } + tertium omnis } } + metalli } } + inanissimi_ } } + } } + _Schistos_ _Glasköpfe oder } } + blütstein_ } } + } } + _Ferri vena _Leber ertz_ } } + jecoris colore_ } } + + _Ferrugo_ _Rüst_ Part limonite Iron rust + + _Magnes_ _Siegelstein Magnetite Lodestone + oder magnet_ + + _Ochra nativa_ _Berg geel_ Limonite Yellow ochre or + ironstone + + _Haematites_ _Blüt stein_ { Part hematite Bloodstone or + { Part jasper ironstone + + _Schistos_ _Glas köpfe_ Part limonite Ironstone + + _Pyrites_ _Kis_ Pyrites Pyrites + + _Pyrites argenti _wasser oder Marcasite *White iron + coloris_ weisser kis_ pyrites + + _Misy_ _Gel atrament_ Part copiapite _Misy_ (see note + on p. 573) + + _Sory_ _Graw und Partly a _Sory_ (see note + schwartz decomposed iron on p. 573) + atrament_ pyrite + + _Melanteria_ _Schwartz und Melanterite _Melanteria_ (see + grau atrament_ (native vitriol) note on p. 573) + +The classification of iron ores on the basis of exterior +characteristics, chiefly hardness and brilliancy, does not justify a +more narrow rendering than "ironstone." Agricola (_De Nat. Fos._, Book +V.) gives elaborate descriptions of various iron ores, but the +descriptions under any special name would cover many actual minerals. +The subject of pyrites is a most confused one; the term originates from +the Greek word for fire, and referred in Greek and Roman times to almost +any stone that would strike sparks. By Agricola it was a generic term in +somewhat the same sense that it is still used in mineralogy, as, for +instance, iron pyrite, copper pyrite, etc. So much was this the case +later on, that Henckel, the leading mineralogist of the 18th Century, +entitled his large volume _Pyritologia_, and in it embraces practically +all the sulphide minerals then known. The term _marcasite_, of mediæval +Arabic origin, seems to have had some vogue prior and subsequent to +Agricola. He, however, puts it on one side as merely a synonym for +pyrite, nor can it be satisfactorily defined in much better terms. +Agricola apparently did not recognise the iron base of pyrites, for he +says (_De Nat. Fos._, p. 366): "Sometimes, however, pyrites do not +contain any gold, silver, copper, or lead, and yet it is not a pure +stone, but a compound, and consists of stone and a substance which is +somewhat metallic, which is a species of its own." Many varieties were +known to him and described, partly by their other metal association, but +chiefly by their colour. + +CADMIA. The minerals embraced under this term by the old mineralogists +form one of the most difficult chapters in the history of mineralogy. +These complexities reached their height with Agricola, for at this time +various new minerals classed under this heading had come under debate. +All these minerals were later found to be forms of zinc, cobalt, or +arsenic, and some of these minerals were in use long prior to Agricola. +From Greek and Roman times down to long after Agricola, brass was made +by cementing zinc ore with copper. Aristotle and Strabo mention an earth +used to colour copper, but give no details. It is difficult to say what +zinc mineral the _cadmium_ of Dioscorides (V, 46) and Pliny (XXXIV, 2), +really was. It was possibly only furnace calamine, or perhaps blende for +it was associated with copper. They amply describe _cadmia_ produced in +copper furnaces, and _pompholyx_ (zinc oxide). It was apparently not +until Theophilus (1150) that the term _calamina_ appears for that +mineral. Precisely when the term "zinc," and a knowledge of the metal, +first appeared in Europe is a matter of some doubt; it has been +attributed to Paracelsus, a contemporary of Agricola (see note on p. +409), but we do not believe that author's work in question was printed +until long after. The quotations from Agricola given below, in which +_zincum_ is mentioned in an obscure way, do not appear in the first +editions of these works, but only in the revised edition of 1559. In +other words, Agricola himself only learned of a substance under this +name a short period before his death in 1555. The metal was imported +into Europe from China prior to this time. He however does describe +actual metallic zinc under the term _conterfei_, and mentions its +occurrence in the cracks of furnace walls. (See also notes on p. 409). + +The word cobalt (German _kobelt_) is from the Greek word _cobalos_, +"mime," and its German form was the term for gnomes and goblins. It +appears that the German miners, finding a material (Agricola's +"corrosive material") which injured their hands and feet, connected it +with the goblins, or used the term as an epithet, and finally it became +established for certain minerals (see note 21, p. 214, on this subject). +The first written appearance of the term in connection with minerals, +appears in Agricola's _Bermannus_ (1530). The first practical use of +cobalt was in the form of _zaffre_ or cobalt blue. There seems to be no +mention of the substance by the Greek or Roman writers, although +analyses of old colourings show some traces of cobalt, but whether +accidental or not is undetermined. The first mention we know of, was by +Biringuccio in 1540 (_De La Pirotechnia_, Book II, Chap. IX.), who did +not connect it with the minerals then called _cobalt_ or _cadmia_. +"_Zaffera_ is another mineral substance, like a metal of middle weight, +which will not melt alone, but accompanied by vitreous substances it +melts into an azure colour so that those who colour glass, or paint +vases or glazed earthenware, make use of it. Not only does it serve for +the above-mentioned operations, but if one uses too great a quantity of +it, it will be black and all other colours, according to the quantity +used." Agricola, although he does not use the word _zaffre_, does refer +to a substance of this kind, and in any event also missed the relation +between _zaffre_ and cobalt, as he seems to think (_De Nat. Fos._, p. +347) that _zaffre_ came from bismuth, a belief that existed until long +after his time. The cobalt of the Erzgebirge was of course, intimately +associated with this mineral. He says, "the slag of bismuth, mixed +together with metalliferous substances, which when melted make a kind of +glass, will tint glass and earthenware vessels blue." _Zaffre_ is the +roasted mineral ground with sand, while _smalt_, a term used more +frequently, is the fused mixture with sand. + +The following are the substances mentioned by Agricola, which, we +believe, relate to cobalt and zinc minerals, some of them arsenical +compounds. Other arsenical minerals we give above. + + _Cadmia fossilis_ _Calmei_; _lapis Calamine Calamine + calaminaris_ + + _Cadmia metallica_ _Kobelt_ Part cobalt *_Cadmia + metallica_ + + _Cadmia fornacis_ _Mitlere und Furnace Furnace accretions + obere accretions or + offenbrüche_ furnace calamine + + _Bituminosa _Kobelt des (Mannsfeld copper _Bituminosa cadmia_ + cadmia_ bergwacht_ schists) (see note 4, + p. 273) + + _Galena inanis_ _Blende_ Sphalerite* *Blende + (Zn S) + + _Cobaltum -- Smallite* } _Cadmia metallica_ + cineraceum_ (CoAs_{2}) } + } + _Cobaltum nigrum_ -- Abolite* } + } + _Cobaltum ferri -- Cobaltite } + colore_ (CoAsS) } + + _Zincum_ _Zinck_ Zinc Zinc + + _Liquor Candidus _Conterfei_ Zinc See note 48, p. 408 + ex fornace ... + etc._ + + _Atramentum -- Goslarite *Native white + sutorium, (Zn SO_{4}) vitriol + candidum, potissimum + reperitur Goselariae_ + + _Spodos _Geeler zechen } Either natural { Grey _spodos_ + subterranea rauch_ } or artificial { + cinerea_ } zinc oxides, { + } no doubt { + _Spodos _Schwartzer } containing { Black _spodos_ + subterranea zechen rauch, } arsenical { + nigra_ auff dem } oxides { + Altenberge } { + nennet man in } { + kis_ } { + } { + _Spodos _Grauer zechen } { Green _spodos_ + subterranea rauch_ } { + viridis_ } { + } { + _Pompholyx_ _Hüttenrauch_ } { _Pompholyx_ (see + } { note 26, p. 394) + +As seen from the following quotations from Agricola, on _cadmia_ and +cobalt, there was infinite confusion as to the zinc, cobalt, and arsenic +minerals; nor do we think any good purpose is served by adding to the +already lengthy discussion of these passages, the obscurity of which is +natural to the state of knowledge; but we reproduce them as giving a +fairly clear idea of the amount of confusion then existing. It is, +however, desirable to bear in mind that the mines familiar to Agricola +abounded in complex mixtures of cobalt, nickel, arsenic, bismuth, zinc, +and antimony. Agricola frequently mentions the garlic odour from _cadmia +metallica_, which, together with the corrosive qualities mentioned +below, would obviously be due to arsenic. _Bermannus_ (p. 459). "This +kind of pyrites miners call _cobaltum_, if it be allowed to me to use +our German name. The Greeks call it _cadmia_. The juices, however, out +of which pyrites and silver are formed, appear to solidify into one +body, and thus is produced what they call _cobaltum_. There are some who +consider this the same as pyrites, because it is almost the same. There +are some who distinguish it as a species, which pleases me, for it has +the distinctive property of being extremely corrosive, so that it +consumes the hands and feet of the workmen, unless they are well +protected, which I do not believe that pyrites can do. Three kinds are +found, and distinguished more by the colour than by other properties; +they are black (abolite?), grey (smallite?), and iron colour (cobalt +glance?). Moreover, it contains more silver than does pyrites...." +_Bermannus_ (p. 431). "It (a sort of pyrites) is so like the colour of +galena that not without cause might anybody have doubt in deciding +whether it be pyrites or galena.... Perhaps this kind is neither pyrites +nor galena, but has a genus of its own. For it has not the colour of +pyrites, nor the hardness. It is almost the colour of galena, but of +entirely different components. From it there is made gold and silver, +and a great quantity is dug out from Reichenstein which is in Silesia, +as was lately reported to me. Much more is found at Raurici, which they +call _zincum_; which species differs from pyrites, for the latter +contains more silver than gold, the former only gold, or hardly any +silver." + +(_De Natura Fossilium_, p. 170). "_Cadmia fossilis_ has an odour like +garlic" ... (p. 367). "We now proceed with _cadmia_, not the _cadmia +fornacis_ (furnace accretions) of which I spoke in the last book, nor +the _cadmia fossilis_ (calamine) devoid of metal, which is used to +colour copper, whose nature I explained in Book V, but the metallic +mineral (_fossilis metallica_), which Pliny states to be an ore from +which copper is made. The Ancients have left no record that another +metal could be smelted from it. Yet it is a fact that not only copper +but also silver may be smelted from it, and indeed occasionally both +copper and silver together. Sometimes, as is the case with pyrites, it +is entirely devoid of metal. It is frequently found in copper mines, but +more frequently still in silver mines. And there are likewise veins of +_cadmia_ itself.... There are several species of the _cadmia fossilis_ +just as there were of _cadmia fornacum_. For one kind has the form of +grapes and another of broken tiles, a third seems to consist of layers. +But the _cadmia fossilis_ has much stronger properties than that which +is produced in the furnaces. Indeed, it often possesses such highly +corrosive power that it corrodes the hands and feet of the miners. It, +therefore, differs from pyrites in colour and properties. For pyrites, +if it does not contain vitriol, is generally either of a gold or silver +colour, rarely of any other. _Cadmia_ is either black or brown or grey, +or else reddish like copper when melted in the furnace.... For this +_cadmia_ is put in a suitable vessel, in the same way as quicksilver, so +that the heat of the fire will cause it to sublimate, and from it is +made a black or brown or grey body which the Alchemists call 'sublimated +_cadmia_' (_cadmiam sublimatam_). This possesses corrosive properties of +the highest degree. Cognate with _cadmia_ and pyrites is a compound +which the Noricians and Rhetians call _zincum_. This contains gold and +silver, and is either red or white. It is likewise found in the Sudetian +mountains, and is devoid of those metals.... With this _cadmia_ is +naturally related mineral _spodos_, known to the Moor Serapion, but +unknown to the Greeks; and also _pompholyx_--for both are produced by +fire where the miners, breaking the hard rocks in drifts, tunnels, and +shafts, burn the _cadmia_ or pyrites or galena or other similar +minerals. From _cadmia_ is made black, brown, and grey _spodos_; from +pyrites, white _pompholyx_ and _spodos_; from galena is made yellow or +grey _spodos_. But _pompholyx_ produced from copper stone (_lapide +aeroso_) after some time becomes green. The black _spodos_, similar to +soot, is found at Altenberg in Meissen. The white _pompholyx_, like wool +which floats in the air in summer, is found in Hildesheim in the seams +in the rocks of almost all quarries except in the sandstone. But the +grey and the brown and the yellow _pompholyx_ are found in those silver +mines where the miners break up the rocks by fire. All consist of very +fine particles which are very light, but the lightest of all is white +_pompholyx_." + +QUARTZ MINERALS. + + _Quarzum_ ("which _Quertz oder Quartz Quartz (see note + Latins call kiselstein_ 15, p. 380) + _silex_") + + _Silex_ _Hornstein oder Flinty or jaspery Hornstone + feurstein_ quartz + + _Crystallum_ _Crystal_ Clear crystals Crystal + + _Achates_ _Achat_ Agate Agate + + _Sarda_ _Carneol_ Carnelian Carnelian + + _Jaspis_ _Jaspis_ Part coloured _Jaspis_ + quartz, part + jade + + _Murrhina_ _Chalcedonius_ Chalcedony Chalcedony + + _Coticula_ _Goldstein_ A black silicious Touchstone (see + stone note 37, p. 252) + + _Amethystus_ _Amethyst_ Amethyst Amethyst + +LIME MINERALS. + + _Lapis } _Gips_ Gypsum Gypsum + specularis_ } + } + _Gypsum_ } + + _Marmor_ _Marmelstein_ Marble Marble + + _Marmor _Alabaster_ Alabaster Alabaster + alabastrites_ + + _Marmor glarea_ -- Calcite (?) Calc spar(?) + + _Saxum calcis_ _Kalchstein_ Limestone Limestone + + _Marga_ _Mergel_ Marl Marl + + _Tophus_ _Toffstein oder Sintry _Tophus_ (see note + topstein_ limestones, 13, p. 233) + stalagmites, + etc. + +MISCELLANEOUS. + + _Amiantus_ _Federwis, pliant Usually asbestos Asbestos + salamanderhar_ + + _Magnetis_ _Silberweis oder } Mica *Mica + katzensilber_ } + } + _Bracteolae -- } + magnetidi simile_ } + } + _Mica_ _Katzensilber } + oder glimmer_ } + + _Silex ex eo ictu -- Feldspar *Feldspar + ferri facile + ignis + elicitur.... + excubus figuris_ + + _Medulla saxorum_ _Steinmarck_ Kaolinite Porcelain clay + + _Fluores (lapides _Flusse_ Fluorspar *Fluorspar + gemmarum simili)_ (see note 15, + p. 380) + + _Marmor in _Spat_ Barite *Heavy spar + metallis + repertum_ + +Apart from the above, many other minerals are mentioned in other +chapters, and some information is given with regard to them in the +footnotes. + +[9] Three _librae_ of silver per _centumpondium_ would be equal to 875 +ounces per short ton. + +[10] As stated in note on p. 2, Agricola divided "stones so called" into +four kinds; the first, common stones in which he included lodestone and +jasper or bloodstone; the second embraced gems; the third were +decorative stones, such as marble, porphyry, etc.; the fourth were +rocks, such as sandstone and limestone. + +LODESTONE. (_Magnes_; _Interpretatio_ gives _Siegelstein oder magnet_). +The lodestone was well-known to the Ancients under various +names--_magnes_, _magnetis_, _heraclion_, and _sideritis_. A review of +the ancient opinions as to its miraculous properties would require more +space than can be afforded. It is mentioned by many Greek writers, +including Hippocrates (460-372 B.C.) and Aristotle; while Theophrastus +(53), Dioscorides (V, 105), and Pliny (XXXIV, 42, XXXVI, 25) describe it +at length. The Ancients also maintained the existence of a stone, +_theamedes_, having repellant properties, and the two were supposed to +exist at times in the same stone. + +EMERY. (_Smiris_; _Interpretatio_ gives _smirgel_). Agricola (_De Natura +Fossilium_, p. 265) says: "The ring-makers polish and clean their hard +gems with _smiris_. The glaziers use it to cut their glass into sheets. +It is found in the silver mines of Annaberg in Meissen and elsewhere." +Stones used for polishing gems are noted by the ancient authors, and +Dana (Syst. of Mineralogy, p. 211) considers the stone of Armenia, of +Theophrastus (77), to be emery, although it could quite well be any hard +stone, such as Novaculite--which is found in Armenia. Dioscorides (V, +166) describes a stone with which the engravers polish gems. + +LAPIS JUDAICUS. (_Interpretatio_ gives _Jüden stein_). This was +undoubtedly a fossil, possibly a _pentremites_. Agricola (_De Natura +Fossilium_, p. 256) says: "It is shaped like an acorn, from the obtuse +end to the point proceed raised lines, all equidistant, etc." Many +fossils were included among the semi-precious stones by the Ancients. +Pliny (XXXVII, 55, 66, 73) describes many such stones, among them the +_balanites_, _phoenicitis_ and the _pyren_, which resemble the above. + +TROCHITIS. (_Interpretatio_ gives _spangen oder rederstein_). This was +also a fossil, probably crinoid stems. Agricola (_De Natura Fossilium_, +p. 256) describes it: "_Trochites_ is so called from a wheel, and is +related to _lapis judaicus_. Nature has indeed given it the shape of a +drum (_tympanum_). The round part is smooth, but on both ends as it were +there is a module from which on all sides there extend radii to the +outer edge, which corresponds with the radii. These radii are so much +raised that it is fluted. The size of these _trochites_ varies greatly, +for the smallest is so little that the largest is ten times as big, and +the largest are a digit in length by a third of a digit in thickness ... +when immersed in vinegar they make bubbles." + +[11] The "extraordinary earths" of Agricola were such substances as +ochres, tripoli, fullers earth, potters' clay, clay used for medicinal +purposes, etc., etc. + +[12] Presumably the ore-body dips into a neighbouring property. + +[13] The various kinds of iron tools are described in great detail in +Book VI. + +[14] Fire-setting as an aid to breaking rock is of very ancient origin, +and moreover it persisted in certain German and Norwegian mines down to +the end of the 19th century--270 years after the first application of +explosives to mining. The first specific reference to fire-setting in +mining is by Agatharchides (2nd century B.C.) whose works are not +extant, but who is quoted by both Diodorus Siculus and Photius, for +which statement see note 8, p. 279. Pliny (XXXIII, 21) says: +"Occasionally a kind of silex is met with, which must be broken with +fire and vinegar, or as the tunnels are filled with suffocating fumes +and smoke, they frequently use bruising machines, carrying 150 _librae_ +of iron." This combination of fire and vinegar he again refers to +(XXIII, 27), where he dilates in the same sentence on the usefulness of +vinegar for breaking rock and for salad dressing. This myth about +breaking rocks with fire and vinegar is of more than usual interest, and +its origin seems to be in the legend that Hannibal thus broke through +the Alps. Livy (59 B.C., 17 A.D.) seems to be the first to produce this +myth in writing; and, in any event, by Pliny's time (23-79 A.D.) it had +become an established method--in literature. Livy (XXI, 37) says, in +connection with Hannibal's crossing of the Alps: "They set fire to it +(the timber) when a wind had arisen suitable to excite the fire, then +when the rock was hot it was crumbled by pouring on vinegar (_infuso +aceto_). In this manner the cliff heated by the fire was broken by iron +tools, and the declivities eased by turnings, so that not only the +beasts of burden but also the elephants could be led down." Hannibal +crossed the Alps in 218 B.C. and Livy's account was written 200 years +later, by which time Hannibal's memory among the Romans was generally +surrounded by Herculean fables. Be this as it may, by Pliny's time the +vinegar was generally accepted, and has been ceaselessly debated ever +since. Nor has the myth ceased to grow, despite the remarks of Gibbon, +Lavalette, and others. A recent historian (Hennebert, _Histoire d' +Annibal_ II, p. 253) of that famous engineer and soldier, soberly sets +out to prove that inasmuch as literal acceptance of ordinary vinegar is +impossible, the Phoenicians must have possessed some mysterious high +explosive. A still more recent biographer swallows this argument _in +toto_. (Morris, "Hannibal," London, 1903, p. 103). A study of the +commentators of this passage, although it would fill a volume with +sterile words, would disclose one generalization: That the real scholars +have passed over the passage with the comment that it is either a +corruption or an old woman's tale, but that hosts of soldiers who set +about the biography of famous generals and campaigns, almost to a man +take the passage seriously, and seriously explain it by way of the rock +being limestone, or snow, or by the use of explosives, or other +foolishness. It has been proposed, although there are grammatical +objections, that the text is slightly corrupt and read _infosso acuto_, +instead of _infuso aceto_, in which case all becomes easy from a mining +point of view. If so, however, it must be assumed that the corruption +occurred during the 20 years between Livy and Pliny. + +By the use of fire-setting in recent times at Königsberg (Arthur L. +Collins, "Fire-setting," Federated Inst. of Mining Engineers, Vol. V, p. +82) an advance of from 5 to 20 feet per month in headings was +accomplished, and on the score of economy survived the use of gunpowder, +but has now been abandoned in favour of dynamite. We may mention that +the use of gunpowder for blasting was first introduced at Schemnitz by +Caspar Weindle, in 1627, but apparently was not introduced into English +mines for nearly 75 years afterward, as the late 17th century English +writers continue to describe fire-setting. + +[15] The strata here enumerated are given in the Glossary of _De Re +Metallica_ as follows:-- + + _Corium terrae_ _Die erd oder leim._ + _Saxum rubrum_ _Rot gebirge._ + _Alterum item rubrum_ _Roterkle._ + _Argilla cinerea_ _Thone._ + _Tertium saxum_ _Gerhulle._ + _Cineris vena_ _Asche._ + _Quartum saxum_ _Gniest._ + _Quintum saxum_ _Schwehlen._ + _Sextum saxum_ _Oberrauchstein._ + _Septimum saxum_ _Zechstein._ + _Octavum saxum_ _Underrauchstein._ + _Nonum saxum_ _Blitterstein._ + _Decimum saxum_ _Oberschuelen._ + _Undecimum saxum_ _Mittelstein._ + _Duodecimum saxum_ _Underschuelen._ + _Decimumtertium saxum_ _Dach._ + _Decimumquartum saxum_ _Norweg._ + _Decimumquintum saxum_ _Lotwerg._ + _Decimumsextum saxum_ _Kamme._ + _Lapis aerosus fissilis_ _Schifer._ + +The description is no doubt that of the Mannsfeld cupriferous slates. It +is of some additional interest as the first attempt at stratigraphic +distinctions, although this must not be taken too literally, for we have +rendered the different numbered "_saxum_" in this connection as +"stratum." The German terms given by Agricola above, can many of them be +identified in the miners' terms to-day for the various strata at +Mannsfeld. Over the _kupferschiefer_ the names to-day are _kammschale_, +_dach_, _faule_, _zechstein_, _rauchwacke_, _rauchstein_, _asche_. The +relative thickness of these beds is much the same as given by Agricola. +The stringers in the 8th stratum of stone, which fuse in the fire of the +second order, were possibly calcite. The _rauchstein_ of the modern +section is distinguished by stringers of calcite, which give it at times +a brecciated appearance. + +[16] The history of surveying and surveying instruments, and in a +subsidiary way their application to mine work, is a subject upon which +there exists a most extensive literature. However, that portion of such +history which relates to the period prior to Agricola represents a much +less proportion of the whole than do the citations to this chapter in +_De Re Metallica_, which is the first comprehensive discussion of the +mining application. The history of such instruments is too extensive to +be entered upon in a footnote, but there are some fundamental +considerations which, if they had been present in the minds of +historical students of this subject, would have considerably abridged +the literature on it. First, there can be no doubt that measuring cords +or rods and boundary stones existed almost from the first division of +land. There is, therefore, no need to try to discover their origins. +Second, the history of surveying and surveying instruments really begins +with the invention of instruments for taking levels, or for the +determination of angles with a view to geometrical calculation. The +meagre facts bearing upon this subject do not warrant the endless +expansion they have received by argument as to what was probable, in +order to accomplish assumed methods of construction among the Ancients. +For instance, the argument that in carrying the Grand Canal over +watersheds with necessary reservoir supply, the Chinese must have had +accurate levelling and surveying instruments before the Christian Era, +and must have conceived in advance a completed work, does not hold water +when any investigation will demonstrate that the canal grew by slow +accretion from the lateral river systems, until it joined almost by +accident. Much the same may be said about the preconception of +engineering results in several other ancient works. There can be no +certainty as to who first invented instruments of the order mentioned +above; for instance, the invention of the dioptra has been ascribed to +Hero, _vide_ his work on the _Dioptra_. He has been assumed to have +lived in the 1st or 2nd Century B.C. Recent investigations, however, +have shown that he lived about 100 A.D. (Sir Thomas Heath, Encyc. Brit. +11th Ed., XIII, 378). As this instrument is mentioned by Vitruvius (50 +-0 B.C.) the myth that Hero was the inventor must also disappear. +Incidentally Vitruvius (VIII, 5) describes a levelling instrument called +a _chorobates_, which was a frame levelled either by a groove of water +or by plumb strings. Be the inventor of the _dioptra_ who he may, Hero's +work on that subject contains the first suggestion of mine surveys in +the problems (XIII, XIV, XV, XVI), where geometrical methods are +elucidated for determining the depths required for the connection of +shafts and tunnels. On the compass we give further notes on p. 56. It +was probably an evolution of the 13th Century. As to the application of +angle- and level-determining instruments to underground surveys, so far +as we know there is no reference prior to Agricola, except that of Hero. +Mr. Bennett Brough (Cantor Lecture, London, 1892) points out that the +_Nützliche Bergbüchlin_ (see Appendix) describes a mine compass, but +there is not the slightest reference to its use for anything but surface +direction of veins. + +Although map-making of a primitive sort requires no instruments, except +legs, the oldest map in the world possesses unusual interest because it +happens to be a map of a mining region. This well-known Turin papyrus +dates from Seti I. (about 1300 B.C.), and it represents certain gold +mines between the Nile and the Red Sea. The best discussion is by Chabas +(_Inscriptions des Mines d'Or_, Chalons-sur-Saone, Paris, 1862, p. +30-36). Fragments of another papyrus, in the Turin Museum, are +considered by Lieblein (_Deux Papyras Hiératiques_, Christiania, 1868) +also to represent a mine of the time of Rameses I. If so, this one dates +from about 1400 B.C. As to an actual map of underground workings +(disregarding illustrations) we know of none until after Agricola's +time. At his time maps were not made, as will be gathered from the text. + +[17] For greater clarity we have in a few places interpolated the terms +"major" and "minor" triangles. + +[18] The names of the instruments here described in the original text, +their German equivalents in the Glossary, and the terms adopted in +translation are given below:-- + + LATIN TEXT. GLOSSARY. TERMS ADOPTED. + + _Funiculus_ -- Cord + + _Pertica_ _Stab_ Rod + + _Hemicyclium_ _Donlege bretlein_ Hemicycle + + _Tripus_ _Stul_ Tripod + + _Instrumentum cui _Compass_ Compass + index_ + + _Orbis_ _Scheube_ Orbis + + _Libra stativa_ _Auffsafz_ Standing plummet + level + + _Libra pensilis_ _Wage_ Suspended plummet + level + + _Instrumentum cui _Der schiner Swiss compass + index Alpinum_ compass_ + + +[19] It is interesting to note that the ratio of any length so obtained, +to the whole length of the staff, is practically equal to the cosine of +the angle represented by the corresponding gradation on the hemicycle; +the gradations on the rod forming a fairly accurate table of cosines. + +[20] It must be understood that instead of "plotting" a survey on a +reduced scale on paper, as modern surveyors do, the whole survey was +reproduced in full scale on the "surveyor's field." + + + + +BOOK VI. + + +Digging of veins I have written of, and the timbering of shafts, +tunnels, drifts, and other excavations, and the art of surveying. I will +now speak first of all, of the iron tools with which veins and rocks are +broken, then of the buckets into which the lumps of earth, rock, metal, +and other excavated materials are thrown, in order that they may be +drawn, conveyed, or carried out. Also, I will speak of the water vessels +and drains, then of the machines of different kinds,[1] and lastly of +the maladies of miners. And while all these matters are being described +accurately, many methods of work will be explained. + +[Illustration 150 (Iron tools): A--First "iron tool." B--Second. +C--Third. D--Fourth.[2] E--Wedge. F--Iron block. G--Iron plate. +H--Wooden handle. I--Handle inserted in first tool.] + +There are certain iron tools which the miners designate by names of +their own, and besides these, there are wedges, iron blocks, iron +plates, hammers, crowbars, pikes, picks, hoes, and shovels. Of those +which are especially referred to as "iron tools" there are four +varieties, which are different from one another in length or thickness, +but not in shape, for the upper end of all of them is broad and square, +so that it can be struck by the hammer. The lower end is pointed so as +to split the hard rocks and veins with its point. All of these have eyes +except the fourth. The first, which is in daily use among miners, is +three-quarters of a foot long, a digit and a half wide, and a digit +thick. The second is of the same width as the first, and the same +thickness, but one and one half feet long, and is used to shatter the +hardest veins in such a way that they crack open. The third is the same +length as the second, but is a little wider and thicker; with this one +they dig the bottoms of those shafts which slowly accumulate water. The +fourth is nearly three palms and one digit long, two digits thick, and +in the upper end it is three digits wide, in the middle it is one palm +wide, and at the lower end it is pointed like the others; with this they +cut out the harder veins. The eye in the first tool is one palm distant +from the upper end, in the second and third it is seven digits distant; +each swells out around the eye on both sides, and into it they fit a +wooden handle, which they hold with one hand, while they strike the iron +tool with a hammer, after placing it against the rock. These tools are +made larger or smaller as necessary. The smiths, as far as possible, +sharpen again all that become dull. + +A wedge is usually three palms and two digits long and six digits wide; +at the upper end, for a distance of a palm, it is three digits thick, +and beyond that point it becomes thinner by degrees, until finally it is +quite sharp. + +The iron block is six digits in length and width; at the upper end it +is two digits thick, and at the bottom a digit and a half. The iron +plate is the same length and width as the iron block, but it is very +thin. All of these, as I explained in the last book, are used when the +hardest kind of veins are hewn out. Wedges, blocks, and plates, are +likewise made larger or smaller. + +[Illustration 151 (Hammers): A--Smallest of the smaller hammers. +B--Intermediate. C--Largest. D--Small kind of the larger hammer. +E--Large kind. F--Wooden handle. G--Handle fixed in the smallest +hammer.] + +Hammers are of two kinds, the smaller ones the miners hold in one hand, +and the larger ones they hold with both hands. The former, because of +their size and use, are of three sorts. With the smallest, that is to +say, the lightest, they strike the second "iron tool;" with the +intermediate one the first "iron tool;" and with the largest the third +"iron tool"; this one is two digits wide and thick. Of the larger sort +of hammers there are two kinds; with the smaller they strike the fourth +"iron tool;" with the larger they drive the wedges into the cracks; the +former are three, and the latter five digits wide and thick, and a foot +long. All swell out in their middle, in which there is an eye for a +handle, but in most cases the handles are somewhat light, in order that +the workmen may be able to strike more powerful blows by the hammer's +full weight being thus concentrated. + +[Illustration 152a (Crowbars): A--Round crowbar. B--Flat crowbar. +C--Pike.] + +The iron crowbars are likewise of two kinds, and each kind is pointed +at one end. One is rounded, and with this they pierce to a shaft full of +water when a tunnel reaches to it; the other is flat, and with this they +knock out of the stopes on to the floor, the rocks which have been +softened by the fire, and which cannot be dislodged by the pike. A +miner's pike, like a sailor's, is a long rod having an iron head. + +[Illustration 152b (Picks): A--Pick. B--Hoe. C--Shovel.] + +The miner's pick differs from a peasant's pick in that the latter is +wide at the bottom and sharp, but the former is pointed. It is used to +dig out ore which is not hard, such as earth. Likewise a hoe and shovel +are in no way different from the common articles, with the one they +scrape up earth and sand, with the other they throw it into vessels. + +Now earth, rock, mineral substances and other things dug out with the +pick or hewn out with the "iron tools" are hauled out of the shaft in +buckets, or baskets, or hide buckets; they are drawn out of tunnels in +wheelbarrows or open trucks, and from both they are sometimes carried in +trays. + +[Illustration 154a (Buckets for hoisting ore)] + +[Illustration 154b (Buckets for hoisting ore): A--Small bucket. B--Large +bucket. C--Staves. D--Iron hoops. E--Iron straps. F--Iron straps on the +bottom. G--Hafts. H--Iron bale. I--Hook of drawing-rope. K--Basket. +L--Hide bucket or sack.] + +Buckets are of two kinds, which differ in size, but not in material or +shape. The smaller for the most part hold only about one _metreta_; the +larger are generally capable of carrying one-sixth of a _congius_; +neither is of unchangeable capacity, but they often vary.[3] Each is +made of staves circled with hoops, one of which binds the top and the +other the bottom. The hoops are sometimes made of hazel and oak, but +these are easily broken by dashing against the shaft, while those made +of iron are more durable. In the larger buckets the staves are thicker +and wider, as also are both hoops, and in order that the buckets may be +more firm and strong, they have eight iron straps, somewhat broad, four +of which run from the upper hoop downwards, and four from the lower hoop +upwards, as if to meet each other. The bottom of each bucket, both +inside and outside, is furnished with two or three straps of iron, which +run from one side of the lower hoop to the other, but the straps which +are on the outside are fixed crosswise. Each bucket has two iron hafts +which project above the edge, and it has an iron semi-circular bale +whose lower ends are fixed directly into the hafts, that the bucket may +be handled more easily. Each kind of bucket is much deeper than it is +wide, and each is wider at the top, in order that the material which is +dug out may be the more easily poured in and poured out again. Into the +smaller buckets strong boys, and into larger ones men, fill earth from +the bottom of the shaft with hoes; or the other material dug up is +shovelled into them or filled in with their hands, for which reason +these men are called "shovellers.[4]" Afterward they fix the hook of the +drawing-rope into the bale; then the buckets are drawn up by +machines--the smaller ones, because of their lighter weight, by machines +turned by men, and the larger ones, being heavier, by the machines +turned by horses. Some, in place of these buckets, substitute baskets +which hold just as much, or even more, since they are lighter than the +buckets; some use sacks made of ox-hide instead of buckets, and the +drawing-rope hook is fastened to their iron bale, usually three of these +filled with excavated material are drawn up at the same time as three +are being lowered and three are being filled by boys. The latter are +generally used at Schneeberg and the former at Freiberg. + +[Illustration 155 (Wheelbarrows): A--Small wheelbarrow. B--Long planks +thereof. C--End-boards. D--Small wheel. E--Larger barrow. F--Front +end-board thereof.] + +That which we call a _cisium_[5] is a vehicle with one wheel, not with +two, such as horses draw. When filled with excavated material it is +pushed by a workman out of tunnels or sheds. It is made as follows: two +planks are chosen about five feet long, one foot wide, and two digits +thick; of each of these the lower side is cut away at the front for a +length of one foot, and at the back for a length of two feet, while the +middle is left whole. Then in the front parts are bored circular holes, +in order that the ends of an axle may revolve in them. The intermediate +parts of the planks are perforated twice near the bottom, so as to +receive the heads of two little cleats on which the planks are fixed; +and they are also perforated in the middle, so as to receive the heads +of two end-boards, while keys fixed in these projecting heads strengthen +the whole structure. The handles are made out of the extreme ends of the +long planks, and they turn downward at the ends that they may be grasped +more firmly in the hands. The small wheel, of which there is only one, +neither has a nave nor does it revolve around the axle, but turns around +with it. From the felloe, which the Greeks called [Greek: apsides], two +transverse spokes fixed into it pass through the middle of the axle +toward the opposite felloe; the axle is square, with the exception of +the ends, each of which is rounded so as to turn in the opening. A +workman draws out this barrow full of earth and rock and draws it back +empty. Miners also have another wheelbarrow, larger than this one, which +they use when they wash earth mixed with tin-stone on to which a stream +has been turned. The front end-board of this one is deeper, in order +that the earth which has been thrown into it may not fall out. + +[Illustration 156 (Trucks): A--Rectangular iron bands on truck. B--Its +iron straps. C--Iron axle. D--Wooden rollers. E--Small iron keys. +F--Large blunt iron pin. G--Same truck upside down.] + +The open truck has a capacity half as large again as a wheelbarrow; it +is about four feet long and about two and a half feet wide and deep; and +since its shape is rectangular, it is bound together with three +rectangular iron bands, and besides these there are iron straps on all +sides. Two small iron axles are fixed to the bottom, around the ends of +which wooden rollers revolve on either side; in order that the rollers +shall not fall off the immovable axles, there are small iron keys. A +large blunt pin fixed to the bottom of the truck runs in a groove of a +plank in such a way that the truck does not leave the beaten track. +Holding the back part with his hands, the carrier pushes out the truck +laden with excavated material, and pushes it back again empty. Some +people call it a "dog"[6], because when it moves it makes a noise which +seems to them not unlike the bark of a dog. This truck is used when they +draw loads out of the longest tunnels, both because it is moved more +easily and because a heavier load can be placed in it. + +[Illustration 157 (Batea): A--Small batea. B--Rope. C--Large batea.] + +Bateas[7] are hollowed out of a single block of wood; the smaller kind +are generally two feet long and one foot wide. When they have been +filled with ore, especially when but little is dug from the shafts and +tunnels, men either carry them out on their shoulders, or bear them away +hung from their necks. Pliny[8] is our authority that among the +ancients everything which was mined was carried out on men's shoulders, +but in truth this method of carrying forth burdens is onerous, since it +causes great fatigue to a great number of men, and involves a large +expenditure for labour; for this reason it has been rejected and +abandoned in our day. The length of the larger batea is as much as three +feet, the width up to a foot and a palm. In these bateas the metallic +earth is washed for the purpose of testing it. + +[Illustration 158a (Buckets for hoisting water): A--Smaller +water-bucket. B--Larger water-bucket. C--Dipper.] + +Water-vessels differ both in the use to which they are put and in the +material of which they are made; some draw the water from the shafts and +pour it into other things, as dippers; while some of the vessels filled +with water are drawn out by machines, as buckets and bags; some are made +of wood, as the dippers and buckets, and others of hides, as the bags. +The water-buckets, just like the buckets which are filled with dry +material, are of two kinds, the smaller and the larger, but these are +unlike the other buckets at the top, as in this case they are narrower, +in order that the water may not be spilled by being bumped against the +timbers when they are being drawn out of the shafts, especially those +considerably inclined. The water is poured into these buckets by +dippers, which are small wooden buckets, but unlike the water-buckets, +they are neither narrow at the top nor bound with iron hoops, but with +hazel,--because there is no necessity for either. The smaller buckets +are drawn up by machines turned by men, the larger ones by those turned +by horses. + +[Illustration 158b (Bags for hoisting water): A--Water-bag which takes +in water by itself. B--Water-bag into which water pours when it is +pushed with a shovel.] + +Our people give the name of water-bags to those very large skins for +carrying water which are made of two, or two and a half, ox-hides. When +these water-bags have undergone much wear and use, first the hair comes +off them and they become bald and shining; after this they become torn. +If the tear is but a small one, a piece of smooth notched stick is put +into the broken part, and the broken bag is bound into its notches on +either side and sewn together; but if it is a large one, they mend it +with a piece of ox-hide. The water-bags are fixed to the hook of a +drawing-chain and let down and dipped into the water, and as soon as +they are filled they are drawn up by the largest machine. They are of +two kinds; the one kind take in the water by themselves; the water pours +into the other kind when it is pushed in a certain way by a wooden +shovel. + +[Illustration 159 (Trough): A--Trough. B--Hopper.] + +When the water has been drawn out from the shafts, it is run off in +troughs, or into a hopper, through which it runs into the trough. +Likewise the water which flows along the sides of the tunnels is carried +off in drains. These are composed of two hollowed beams joined firmly +together, so as to hold the water which flows through them, and they are +covered by planks all along their course, from the mouth of the tunnel +right up to the extreme end of it, to prevent earth or rock falling into +them and obstructing the flow of the water. If much mud gradually +settles in them the planks are raised and the drains are cleaned out, +for they would otherwise become stopped up and obstructed by this +accident. With regard to the trough lying above ground, which miners +place under the hoppers which are close by the shaft houses, these are +usually hollowed out of single trees. Hoppers are generally made of four +planks, so cut on the lower side and joined together that the top part +of the hopper is broader and the bottom part narrower. + +I have sufficiently indicated the nature of the miners' iron tools and +their vessels. I will now explain their machines, which are of three +kinds, that is, hauling machines, ventilating machines, and ladders. By +means of the hauling machines loads are drawn out of the shafts; the +ventilating machines receive the air through their mouths and blow it +into shafts or tunnels, for if this is not done, diggers cannot carry on +their labour without great difficulty in breathing; by the steps of the +ladders the miners go down into the shafts and come up again. + +[Illustration 161 (Windlass): A--Timber placed in front of the shaft. +B--Timber placed at the back of the shaft. C--Pointed stakes. +D--Cross-timbers. E--Posts or thick planks. F--Iron sockets. G--Barrel. +H--Ends of barrel. I--Pieces of wood. K--handle. L--Drawing-rope. M--Its +hook. N--Bucket. O--Bale of the bucket.] + +Hauling machines are of varied and diverse forms, some of them being +made with great skill, and if I am not mistaken, they were unknown to +the Ancients. They have been invented in order that water may be drawn +from the depths of the earth to which no tunnels reach, and also the +excavated material from shafts which are likewise not connected with a +tunnel, or if so, only with very long ones. Since shafts are not all of +the same depth, there is a great variety among these hauling machines. +Of those by which dry loads are drawn out of the shafts, five sorts are +in the most common use, of which I will now describe the first. Two +timbers a little longer than the shaft are placed beside it, the one in +the front of the shaft, the other at the back. Their extreme ends have +holes through which stakes, pointed at the bottom like wedges, are +driven deeply into the ground, so that the timbers may remain +stationary. Into these timbers are mortised the ends of two +cross-timbers, one laid on the right end of the shaft, while the other +is far enough from the left end that between it and that end there +remains suitable space for placing the ladders. In the middle of the +cross-timbers, posts are fixed and secured with iron keys. In hollows at +the top of these posts thick iron sockets hold the ends of the barrel, +of which each end projects beyond the hollow of the post, and is +mortised into the end of another piece of wood a foot and a half long, a +palm wide and three digits thick; the other end of these pieces of wood +is seven digits wide, and into each of them is fixed a round handle, +likewise a foot and a half long. A winding-rope is wound around the +barrel and fastened to it at the middle part. The loop at each end of +the rope has an iron hook which is engaged in the bale of a bucket, and +so when the windlass revolves by being turned by the cranks, a loaded +bucket is always being drawn out of the shaft and an empty one is being +sent down into it. Two robust men turn the windlass, each having a +wheelbarrow near him, into which he unloads the bucket which is drawn up +nearest to him; two buckets generally fill a wheelbarrow; therefore when +four buckets have been drawn up, each man runs his own wheelbarrow out +of the shed and empties it. Thus it happens that if shafts are dug deep, +a hillock rises around the shed of the windlass. If a vein is not +metal-bearing, they pour out the earth and rock without discriminating; +whereas if it is metal-bearing, they preserve these materials, which +they unload separately and crush and wash. When they draw up buckets of +water they empty the water through the hopper into a trough, through +which it flows away. + +[Illustration 162 (Windlass): A--Barrel. B--Straight levers. C--Usual +crank. D--Spokes of wheel. E--Rim of the same wheel.] + +The next kind of machine, which miners employ when the shaft is deeper, +differs from the first in that it possesses a wheel as well as cranks. +This windlass, if the load is not being drawn up from a great depth, is +turned by one windlass man, the wheel taking the place of the other man. +But if the depth is greater, then the windlass is turned by three men, +the wheel being substituted for a fourth, because the barrel having been +once set in motion, the rapid revolutions of the wheel help, and it can +be turned more easily. Sometimes masses of lead are hung on to this +wheel, or are fastened to the spokes, in order that when it is turned +they depress the spokes by their weight and increase the motion; some +persons for the same reason fasten into the barrel two, three, or four +iron rods, and weight their ends with lumps of lead. The windlass wheel +differs from the wheel of a carriage and from the one which is turned +by water power, for it lacks the buckets of a water-wheel and it lacks +the nave of a carriage wheel. In the place of the nave it has a thick +barrel, in which are mortised the lower ends of the spokes, just as +their upper ends are mortised into the rim. When three windlass men turn +this machine, four straight levers are fixed to the one end of the +barrel, and to the other the crank which is usual in mines, and which is +composed of two limbs, of which the rounded horizontal one is grasped by +the hands; the rectangular limb, which is at right angles to the +horizontal one, has mortised in its lower end the round handle, and in +the upper end the end of the barrel. This crank is worked by one man, +the levers by two men, of whom one pulls while the other pushes; all +windlass workers, whatsoever kind of a machine they may turn, are +necessarily robust that they can sustain such great toil. + +[Illustration 163 (Tread whim): A--Upright axle. B--Block. C--Roof beam. +D--Wheel. E--Toothed-drum. F--Horizontal axle. G--Drum composed of +rundles. H--Drawing rope. I--Pole. K--Upright posts. L--Cleats on the +wheel.] + +The third kind of machine is less fatiguing for the workman, while it +raises larger loads; even though it is slower, like all other machines +which have drums, yet it reaches greater depths, even to a depth of 180 +feet. It consists of an upright axle with iron journals at its +extremities, which turn in two iron sockets, the lower of which is fixed +in a block set in the ground and the upper one in the roof beam. This +axle has at its lower end a wheel made of thick planks joined firmly +together, and at its upper end a toothed drum; this toothed drum turns +another drum made of rundles, which is on a horizontal axle. A +winding-rope is wound around this latter axle, which turns in iron +bearings set in the beams. So that they may not fall, the two workmen +grasp with their hands a pole fixed to two upright posts, and then +pushing the cleats of the lower wheel backward with their feet, they +revolve the machine; as often as they have drawn up and emptied one +bucket full of excavated material, they turn the machine in the opposite +direction and draw out another. + +[Illustration 165 (Horse whim): A--Upright beams. B--Sills laid flat +upon the ground. C--Posts. D--Area. E--Sill set at the bottom of the +hole. F--Axle. G--Double cross-beams. H--Drum. I--Winding-ropes. +K--Bucket. L--Small pieces of wood hanging from double cross-beams. +M--Short wooden block. N--Chain. O--Pole bar. P--Grappling hook. (Some +members mentioned in the text are not shown).] + +The fourth machine raises burdens once and a half as large again as the +two machines first explained. When it is made, sixteen beams are erected +each forty feet long, one foot thick and one foot wide, joined at the +top with clamps and widely separated at the bottom. The lower ends of +all of them are mortised into separate sills laid flat upon the ground; +these sills are five feet long, a foot and a half wide, and a foot +thick. Each beam is also connected with its sill by a post, whose upper +end is mortised into the beam and its lower end mortised into the sill; +these posts are four feet long, one foot thick, and one foot wide. Thus +a circular area is made, the diameter of which is fifty feet; in the +middle of this area a hole is sunk to a depth of ten feet, and rammed +down tight, and in order to give it sufficient firmness, it is +strengthened with contiguous small timbers, through which pins are +driven, for by them the earth around the hole is held so that it cannot +fall in. In the bottom of the hole is planted a sill, three or four feet +long and a foot and a half thick and wide; in order that it may remain +fixed, it is set into the small timbers; in the middle of it is a steel +socket in which the pivot of the axle turns. In like manner a timber is +mortised into two of the large beams, at the top beneath the clamps; +this has an iron bearing in which the other iron journal of the axle +revolves. Every axle used in mining, to speak of them once for all, has +two iron journals, rounded off on all sides, one fixed with keys in the +centre of each end. That part of this journal which is fixed to the end +of the axle is as broad as the end itself and a digit thick; that which +projects beyond the axle is round and a palm thick, or thicker if +necessity requires; the ends of each miner's axle are encircled and +bound by an iron band to hold the journal more securely. The axle of +this machine, except at the ends, is square, and is forty feet long, a +foot and a half thick and wide. Mortised and clamped into the axle above +the lower end are the ends of four inclined beams; their outer ends +support two double cross-beams similarly mortised into them; the +inclined beams are eighteen feet long, three palms thick, and five wide. +The two cross-beams are fixed to the axle and held together by wooden +keys so that they will not separate, and they are twenty-four feet long. +Next, there is a drum which is made of three wheels, of which the middle +one is seven feet distant from the upper one and from the lower one; the +wheels have four spokes which are supported by the same number of +inclined braces, the lower ends of which are joined together round the +axle by a clamp; one end of each spoke is mortised into the axle and the +other into the rim. There are rundles all round the wheels, reaching +from the rim of the lowest one to the rim of the middle one, and +likewise from the rim of the middle wheel to the rim of the top one; +around these rundles are wound the drawing-ropes, one between the lowest +wheel and the middle one, the other between the middle and top wheels. +The whole of this construction is shaped like a cone, and is covered +with a shingle roof, with the exception of that square part which faces +the shaft. Then cross-beams, mortised at both ends, connect a double row +of upright posts; all of these are eighteen feet long, but the posts are +one foot thick and one foot wide, and the cross-beams are three palms +thick and wide. There are sixteen posts and eight cross-beams, and upon +these cross-beams are laid two timbers a foot wide and three palms +thick, hollowed out to a width of half a foot and to a depth of five +digits; the one is laid upon the upper cross-beams and the other upon +the lower; each is long enough to reach nearly from the drum of the whim +to the shaft. Near the same drum each timber has a small round wooden +roller six digits thick, whose ends are covered with iron bands and +revolve in iron rings. Each timber also has a wooden pulley, which +together with its iron axle revolves in holes in the timber. These +pulleys are hollowed out all round, in order that the drawing-rope may +not slip out of them, and thus each rope is drawn tight and turns over +its own roller and its own pulley. The iron hook of each rope is engaged +with the bale of the bucket. Further, with regard to the double +cross-beams which are mortised to the lower part of the main axle, to +each end of them there is mortised a small piece of wood four feet long. +These appear to hang from the double cross-beams, and a short wooden +block is fixed to the lower part of them, on which a driver sits. Each +of these blocks has an iron clavis which holds a chain, and that in turn +a pole-bar. In this way it is possible for two horses to draw this whim, +now this way and now that; turn by turn one bucket is drawn out of the +shaft full and another is let down into it empty; if, indeed, the shaft +is very deep four horses turn the whim. When a bucket has been drawn up, +whether filled with dry or wet materials, it must be emptied, and a +workman inserts a grappling hook and overturns it; this hook hangs on a +chain made of three or four links, fixed to a timber. + +[Illustration 167 (Horse whim): A--Toothed drum which is on the upright +axle. B--Horizontal axle. C--Drum which is made of rundles. D--Wheel +near it. E--Drum made of hubs. F--Brake. G--Oscillating beam. H--Short +beam. I--Hook.] + +The fifth machine is partly like the whim, and partly like the third rag +and chain pump, which draws water by balls when turned by horse power, +as I will explain a little later. Like this pump, it is turned by horse +power and has two axles, namely, an upright one--about whose lower end, +which descends into an underground chamber, there is a toothed drum--and +a horizontal one, around which there is a drum made of rundles. It has +indeed two drums around its horizontal axle, similar to those of the big +machine, but smaller, because it draws buckets from a shaft almost two +hundred and forty feet deep. One drum is made of hubs to which cleats +are fixed, and the other is made of rundles; and near the latter is a +wheel two feet deep, measured on all sides around the axle, and one foot +wide; and against this impinges a brake,[10] which holds the whim when +occasion demands that it be stopped. This is necessary when the hide +buckets are emptied after being drawn up full of rock fragments or +earth, or as often as water is poured out of buckets similarly drawn up; +for this machine not only raises dry loads, but also wet ones, just like +the other four machines which I have already described. By this also, +timbers fastened on to its winding-chain are let down into a shaft. The +brake is made of a piece of wood one foot thick and half a foot long, +projecting from a timber that is suspended by a chain from one end of a +beam which oscillates on an iron pin, this in turn being supported in +the claws of an upright post; and from the other end of this oscillating +beam a long timber is suspended by a chain, and from this long timber +again a short beam is suspended. A workman sits on the short beam when +the machine needs to be stopped, and lowers it; he then inserts a plank +or small stick so that the two timbers are held down and cannot be +raised. In this way the brake is raised, and seizing the drum, presses +it so tightly that sparks often fly from it; the suspended timber to +which the short beam is attached, has several holes in which the chain +is fixed, so that it may be raised as much as is convenient. Above +this wheel there are boards to prevent the water from dripping down and +wetting it, for if it becomes wet the brake will not grip the machine so +well. Near the other drum is a pin from which hangs a chain, in the last +link of which there is an iron hook three feet long; a ring is fixed to +the bottom of the bucket, and this hook, being inserted into it, holds +the bucket back so that the water may be poured out or the fragments of +rock emptied. + +[Illustration 168 (Sleigh for Ore): A--Sledge with box placed on it. +B--Sledge with sacks placed on it. C--Stick. D--Dogs with pack-saddles. +E--Pigskin sacks tied to a rope.] + +The miners either carry, draw, or roll down the mountains the ore which +is hauled out of the shafts by these five machines or taken out of the +tunnels. In the winter time our people place a box on a sledge and draw +it down the low mountains with a horse; and in this season they also +fill sacks made of hide and load them on dogs, or place two or three of +them on a small sledge which is higher in the fore part and lower at the +back. Sitting on these sacks, not without risk of his life, the bold +driver guides the sledge as it rushes down the mountain into the valleys +with a stick, which he carries in his hand; when it is rushing down too +quickly he arrests it with the stick, or with the same stick brings it +back to the track when it is turning aside from its proper course. Some +of the Noricians[11] collect ore during the winter into sacks made of +bristly pigskins, and drag them down from the highest mountains, which +neither horses, mules nor asses can climb. Strong dogs, that are trained +to bear pack saddles, carry these sacks when empty into the mountains. +When they are filled with ore, bound with thongs, and fastened to a +rope, a man, winding the rope round his arm or breast, drags them down +through the snow to a place where horses, mules, or asses bearing +pack-saddles can climb. There the ore is removed from the pigskin sacks +and put into other sacks made of double or triple twilled linen thread, +and these placed on the pack-saddles of the beasts are borne down to the +works where the ores are washed or smelted. If, indeed, the horses, +mules, or asses are able to climb the mountains, linen sacks filled with +ore are placed on their saddles, and they carry these down the narrow +mountain paths, which are passable neither by wagons nor sledges, into +the valleys lying below the steeper portions of the mountains. But on +the declivity of cliffs which beasts cannot climb, are placed long open +boxes made of planks, with transverse cleats to hold them together; into +these boxes is thrown the ore which has been brought in wheelbarrows, +and when it has run down to the level it is gathered into sacks, and the +beasts either carry it away on their backs or drag it away after it has +been thrown into sledges or wagons. When the drivers bring ore down +steep mountain slopes they use two-wheeled carts, and they drag behind +them on the ground the trunks of two trees, for these by their weight +hold back the heavily-laden carts, which contain ore in their boxes, and +check their descent, and but for these the driver would often be obliged +to bind chains to the wheels. When these men bring down ore from +mountains which do not have such declivities, they use wagons whose beds +are twice as long as those of the carts. The planks of these are so put +together that, when the ore is unloaded by the drivers, they can be +raised and taken apart, for they are only held together by bars. The +drivers employed by the owners of the ore bring down thirty or sixty +wagon-loads, and the master of the works marks on a stick the number of +loads for each driver. But some ore, especially tin, after being taken +from the mines, is divided into eight parts, or into nine, if the owners +of the mine give "ninth parts" to the owners of the tunnel. This is +occasionally done by measuring with a bucket, but more frequently planks +are put together on a spot where, with the addition of the level ground +as a base, it forms a hollow box. Each owner provides for removing, +washing, and smelting that portion which has fallen to him. +(Illustration p. 170). + +[Illustration 170 (Wagons for Hauling Ore): A--Horses with pack-saddles. +B--Long box placed on the slope of the cliff. C--Cleats thereof. +D--Wheelbarrow. E--Two-wheeled cart. F--Trunks of trees. G--Wagon. +H--Ore being unloaded from the wagon. I--Bars. K--Master of the works +marking the number of carts on a stick. L--Boxes into which are thrown +the ore which has to be divided.] + +Into the buckets, drawn by these five machines, the boys or men throw +the earth and broken rock with shovels, or they fill them with their +hands; hence they get their name of shovellers. As I have said, the same +machines raise not only dry loads, but also wet ones, or water; but +before I explain the varied and diverse kinds of machines by which +miners are wont to draw water alone, I will explain how heavy bodies, +such as axles, iron chains, pipes, and heavy timbers, should be lowered +into deep vertical shafts. A windlass is erected whose barrel has on +each end four straight levers; it is fixed into upright beams and around +it is wound a rope, one end of which is fastened to the barrel and the +other to those heavy bodies which are slowly lowered down by workmen; +and if these halt at any part of the shaft they are drawn up a little +way. When these bodies are very heavy, then behind this windlass another +is erected just like it, that their combined strength may be equal to +the load, and that it may be lowered slowly. Sometimes for the same +reason, a pulley is fastened with cords to the roof-beam, and the rope +descends and ascends over it. + +[Illustration 171 (Windlass): A--Windlass. B--Straight levers. +C--Upright beams. D--Rope. E--Pulley. F--Timbers to be lowered.] + +Water is either hoisted or pumped out of shafts. It is hoisted up after +being poured into buckets or water-bags; the water-bags are generally +brought up by a machine whose water-wheels have double paddles, while +the buckets are brought up by the five machines already described, +although in certain localities the fourth machine also hauls up +water-bags of moderate size. Water is drawn up also by chains of +dippers, or by suction pumps, or by "rag and chain" pumps.[12] When +there is but a small quantity, it is either brought up in buckets or +drawn up by chains of dippers or suction pumps, and when there is much +water it is either drawn up in hide bags or by rag and chain pumps. + +[Illustration 173 (Chain Pumps): A--Iron frame. B--Lowest axle. +C--Fly-wheel. D--Smaller drum made of rundles. E--Second axle. +F--Smaller toothed wheel. G--Larger drum made of rundles. H--Upper axle. +I--Larger toothed wheel. K--Bearings. L--Pillow. M--Framework. N--Oak +timber. O--Support of iron bearing. P--Roller. Q--Upper drum. R--Clamps. +S--Chain. T--Links. V--Dippers. X--Crank. Y--Lower drum or balance +weight.] + +First of all, I will describe the machines which draw water by chains of +dippers, of which there are three kinds. For the first, a frame is made +entirely of iron bars; it is two and a half feet high, likewise two and +a half feet long, and in addition one-sixth and one-quarter of a digit +long, one-fourth and one-twenty-fourth of a foot wide. In it there are +three little horizontal iron axles, which revolve in bearings or wide +pillows of steel, and also four iron wheels, of which two are made with +rundles and the same number are toothed. Outside the frame, around the +lowest axle, is a wooden fly-wheel, so that it can be more readily +turned, and inside the frame is a smaller drum which is made of eight +rundles, one-sixth and one twenty-fourth of a foot long. Around the +second axle, which does not project beyond the frame, and is therefore +only two and a half feet and one-twelfth and one-third part of a digit +long, there is on the one side, a smaller toothed wheel, which has +forty-eight teeth, and on the other side a larger drum, which is +surrounded by twelve rundles one-quarter of a foot long. Around the +third axle, which is one inch and one-third thick, is a larger toothed +wheel projecting one foot from the axle in all directions, which has +seventy-two teeth. The teeth of each wheel are fixed in with screws, +whose threads are screwed into threads in the wheel, so that those teeth +which are broken can be replaced by others; both the teeth and rundles +are steel. The upper axle projects beyond the frame, and is so skilfully +mortised into the body of another axle that it has the appearance of +being one; this axle proceeds through a frame made of beams which stands +around the shaft, into an iron fork set in a stout oak timber, and turns +on a roller made of pure steel. Around this axle is a drum of the kind +possessed by those machines which draw water by rag and chain; this drum +has triple curved iron clamps, to which the links of an iron chain hook +themselves, so that a great weight cannot tear them away. These links +are not whole like the links of other chains, but each one being curved +in the upper part on each side catches the one which comes next, whereby +it presents the appearance of a double chain. At the point where one +catches the other, dippers made of iron or brass plates and holding half +a _congius_[13] are bound to them with thongs; thus, if there are one +hundred links there will be the same number of dippers pouring out +water. When the shafts are inclined, the mouths of the dippers project +and are covered on the top that they may not spill out the water, but +when the shafts are vertical the dippers do not require a cover. By +fitting the end of the lowest small axle into the crank, the man who +works the crank turns the axle, and at the same time the drum whose +rundles turn the toothed wheel of the second axle; by this wheel is +driven the one that is made of rundles, which again turns the toothed +wheel of the upper small axle and thus the drum to which the clamps are +fixed. In this way the chain, together with the empty dippers, is slowly +let down, close to the footwall side of the vein, into the sump to the +bottom of the balance drum, which turns on a little iron axle, both ends +of which are set in a thick iron bearing. The chain is rolled round the +drum and the dippers fill with water; the chain being drawn up close to +the hangingwall side, carries the dippers filled with water above the +drum of the upper axle. Thus there are always three of the dippers +inverted and pouring water into a lip, from which it flows away into the +drain of the tunnel. This machine is less useful, because it cannot be +constructed without great expense, and it carries off but little water +and is somewhat slow, as also are other machines which possess a great +number of drums. + +[Illustration 174 (Chain Pumps): A--Wheel which is turned by treading. +B--Axle. C--Double chain. D--Link of double chain. E--Dippers. F--Simple +clamps. G--Clamp with triple curves.] + +The next machine of this kind, described in a few words by +Vitruvius,[14] more rapidly brings up dippers, holding a _congius_; for +this reason, it is more useful than the first one for drawing water out +of shafts, into which much water is continually flowing. This machine +has no iron frame nor drums, but has around its axle a wooden wheel +which is turned by treading; the axle, since it has no drum, does not +last very long. In other respects this pump resembles the first kind, +except that it differs from it by having a double chain. Clamps should +be fixed to the axle of this machine, just as to the drum of the other +one; some of these are made simple and others with triple curves, but +each kind has four barbs. + +[Illustration 175 (Chain Pumps): A--Wheel whose paddles are turned by +the force of the stream. B--Axle. C--Drum of axle, to which clamps are +fixed. D--Chain. E--Link. F--Dippers. G--Balance drum.] + +The third machine, which far excels the two just described, is made when +a running stream can be diverted to a mine; the impetus of the stream +striking the paddles revolves a water-wheel in place of the wheel turned +by treading. With regard to the axle, it is like the second machine, but +the drum which is round the axle, the chain, and the balance drum, are +like the first machine. It has much more capacious dippers than even the +second machine, but since the dippers are frequently broken, miners +rarely use these machines; for they prefer to lift out small quantities +of water by the first five machines or to draw it up by suction pumps, +or, if there is much water, to drain it by the rag and chain pump or to +bring it up in water-bags. + +[Illustration 177 (Suction Pumps): A--Sump. B--Pipes. C--Flooring. +D--Trunk. E--Perforations of trunk. F--Valve. G--Spout. H--Piston-rod. +I--Hand-bar of piston. K--Shoe. L--Disc with round openings. M--Disc +with oval openings. N--Cover. O--This man is boring logs and making them +into pipes. P--Borer with auger. Q--Wider borer.] + +Enough, then, of the first sort of pumps. I will now explain the other, +that is the pump which draws, by means of pistons, water which has been +raised by suction. Of these there are seven varieties, which though they +differ from one another in structure, nevertheless confer the same +benefits upon miners, though some to a greater degree than others. The +first pump is made as follows. Over the sump is placed a flooring, +through which a pipe--or two lengths of pipe, one of which is joined +into the other--are let down to the bottom of the sump; they are +fastened with pointed iron clamps driven in straight on both sides, so +that the pipes may remain fixed. The lower end of the lower pipe is +enclosed in a trunk two feet deep; this trunk, hollow like the pipe, +stands at the bottom of the sump, but the lower opening of it is blocked +with a round piece of wood; the trunk has perforations round about, +through which water flows into it. If there is one length of pipe, then +in the upper part of the trunk which has been hollowed out there is +enclosed a box of iron, copper, or brass, one palm deep, but without a +bottom, and a rounded valve so tightly closes it that the water, which +has been drawn up by suction, cannot run back; but if there are two +lengths of pipe, the box is enclosed in the lower pipe at the point of +junction. An opening or a spout in the upper pipe reaches to the drain +of the tunnel. Thus the workman, eager at his labour, standing on the +flooring boards, pushes the piston down into the pipe and draws it out +again. At the top of the piston-rod is a hand-bar and the bottom is +fixed in a shoe; this is the name given to the leather covering, which +is almost cone-shaped, for it is so stitched that it is tight at the +lower end, where it is fixed to the piston-rod which it surrounds, but +in the upper end where it draws the water it is wide open. Or else an +iron disc one digit thick is used, or one of wood six digits thick, each +of which is far superior to the shoe. The disc is fixed by an iron key +which penetrates through the bottom of the piston-rod, or it is screwed +on to the rod; it is round, with its upper part protected by a cover, +and has five or six openings, either round or oval, which taken together +present a star-like appearance; the disc has the same diameter as the +inside of the pipe, so that it can be just drawn up and down in it. When +the workman draws the piston up, the water which has passed in at the +openings of the disc, whose cover is then closed, is raised to the hole +or little spout, through which it flows away; then the valve of the box +opens, and the water which has passed into the trunk is drawn up by the +suction and rises into the pipe; but when the workman pushes down the +piston, the valve closes and allows the disc again to draw in the water. + +[Illustration 178 (Suction Pumps): A--Erect timber. B--Axle. C--Sweep +which turns about the axle. D--Piston rod. E--Cross-bar. F--Ring with +which two pipes are generally joined.] + +The piston of the second pump is more easily moved up and down. When +this pump is made, two beams are placed over the sump, one near the +right side of it, and the other near the left. To one beam a pipe is +fixed with iron clamps; to the other is fixed either the forked branch +of a tree or a timber cut out at the top in the shape of a fork, and +through the prongs of the fork a round hole is bored. Through a wide +round hole in the middle of a sweep passes an iron axle, so fastened +in the holes in the fork that it remains fixed, and the sweep turns on +this axle. In one end of the sweep the upper end of a piston-rod is +fastened with an iron key; at the other end a cross-bar is also fixed, +to the extreme ends of which are handles to enable it to be held more +firmly in the hands. And so when the workman pulls the cross-bar upward, +he forces the piston into the pipe; when he pushes it down again he +draws the piston out of the pipe; and thus the piston carries up the +water which has been drawn in at the openings of the disc, and the water +flows away through the spout into the drains. This pump, like the next +one, is identical with the first in all that relates to the piston, +disc, trunk, box, and valve. + +[Illustration 179 (Suction Pumps): A--Posts. B--Axle. C--Wooden bars. +D--Piston rod. E--Short piece of wood. F--Drain. G--This man is +diverting the water which is flowing out of the drain, to prevent it +from flowing into the trenches which are being dug.] + +The third pump is not unlike the one just described, but in place of one +upright, posts are erected with holes at the top, and in these holes the +ends of an axle revolve. To the middle of this axle are fixed two wooden +bars, to the end of one of which is fixed the piston, and to the end of +the other a heavy piece of wood, but short, so that it can pass between +the two posts and may move backward and forward. When the workman pushes +this piece of wood, the piston is drawn out of the pipe; when it returns +by its own weight, the piston is pushed in. In this way, the water +which the pipe contains is drawn through the openings in the disc and +emptied by the piston through the spout into the drain. There are some +who place a hand-bar underneath in place of the short piece of wood. +This pump, as also the last before described, is less generally used +among miners than the others. + +[Illustration 180 (Duplex suction Pumps): A--Box. B--Lower part of box. +C--Upper part of same. D--Clamps. E--Pipes below the box. F--Column pipe +fixed above the box. G--Iron axle. H--Piston-rods. I--Washers to protect +the bearings. K--Leathers. L--Eyes in the axle. M--Rods whose ends are +weighted with lumps of lead. N--Crank. (_This plate is unlettered in the +first edition but corrected in those later._)] + +The fourth kind is not a simple pump but a duplex one. It is made as +follows. A rectangular block of beechwood, five feet long, two and a +half feet wide, and one and a half feet thick, is cut in two and +hollowed out wide and deep enough so that an iron axle with cranks can +revolve in it. The axle is placed between the two halves of this box, +and the first part of the axle, which is in contact with the wood, is +round and the straight end forms a journal. Then the axle is bent down +the depth of a foot and again bent so as to continue straight, and at +this point a round piston-rod hangs from it; next it is bent up as far +as it was bent down; then it continues a little way straight again, and +then it is bent up a foot and again continues straight, at which point a +second round piston-rod is hung from it; afterward it is bent down the +same distance as it was bent up the last time; the other end of it, +which also acts as a journal, is straight. This part which protrudes +through the wood is protected by two iron washers in the shape of discs, +to which are fastened two leather washers of the same shape and size, in +order to prevent the water which is drawn into the box from gushing out. +These discs are around the axle; one of them is inside the box and the +other outside. Beyond this, the end of the axle is square and has two +eyes, in which are fixed two iron rods, and to their ends are weighted +lumps of lead, so that the axle may have a greater propensity to +revolve; this axle can easily be turned when its end has been mortised +in a crank. The upper part of the box is the shallower one, and the +lower part the deeper; the upper part is bored out once straight down +through the middle, the diameter of the opening being the same as the +outside diameter of the column pipe; the lower box has, side by side, +two apertures also bored straight down; these are for two pipes, the +space of whose openings therefore is twice as great as that of the upper +part; this lower part of the box is placed upon the two pipes, which are +fitted into it at their upper ends, and the lower ends of these pipes +penetrate into trunks which stand in the sump. These trunks have +perforations through which the water flows into them. The iron axle is +placed in the inside of the box, then the two iron piston-rods which +hang from it are let down through the two pipes to the depth of a foot. +Each piston has a screw at its lower end which holds a thick iron plate, +shaped like a disc and full of openings, covered with a leather, and +similarly to the other pump it has a round valve in a little box. Then +the upper part of the box is placed upon the lower one and properly +fitted to it on every side, and where they join they are bound by wide +thick iron plates, and held with small wide iron wedges, which are +driven in and are fastened with clamps. The first length of column pipe +is fixed into the upper part of the box, and another length of pipe +extends it, and a third again extends this one, and so on, another +extending on another, until the uppermost one reaches the drain of the +tunnel. When the crank worker turns the axle, the pistons in turn draw +the water through their discs; since this is done quickly, and since the +area of openings of the two pipes over which the box is set, is twice as +large as the opening of the column pipe which rises from the box, and +since the pistons do not lift the water far up, the impetus of the water +from the lower pipes forces it to rise and flow out of the column pipe +into the drain of the tunnel. Since a wooden box frequently cracks open, +it is better to make it of lead or copper or brass. + +[Illustration 182 (Suction Pumps): A--Tappets of piston-rods. B--Cams of +the barrel. C--Square upper parts of piston-rods. D--Lower rounded parts +of piston-rods. E--Cross-beams. F--Pipes. G--Apertures of pipes. +H--Trough. (Fifth kind of pump--see p. 181).] + +The fifth kind of pump is still less simple, for it is composed of two +or three pumps whose pistons are raised by a machine turned by men, for +each piston-rod has a tappet which is raised, each in succession, by two +cams on a barrel; two or four strong men turn it. When the pistons +descend into the pipes their discs draw the water; when they are raised +these force the water out through the pipes. The upper part of each of +these piston-rods, which is half a foot square, is held in a slot in a +cross-beam; the lower part, which drops down into the pipes, is made of +another piece of wood and is round. Each of these three pumps is +composed of two lengths of pipe fixed to the shaft timbers. This +machine draws the water higher, as much as twenty-four feet. If the +diameter of the pipes is large, only two pumps are made; if smaller, +three, so that by either method the volume of water is the same. This +also must be understood regarding the other machines and their pipes. +Since these pumps are composed of two lengths of pipe, the little iron +box having the iron valve which I described before, is not enclosed in a +trunk, but is in the lower length of pipe, at that point where it joins +the upper one; thus the rounded part of the piston-rod is only as long +as the upper length of pipe; but I will presently explain this more +clearly. + +[Illustration 183 (Suction Pumps): A--Water-wheel. B--Axle. C--Trunk on +which the lowest pipe stands. D--Basket surrounding trunk. (Sixth kind +of pump--see p. 184.)] + +The sixth kind of pump would be just the same as the fifth were it not +that it has an axle instead of a barrel, turned not by men but by a +water-wheel, which is revolved by the force of water striking its +buckets. Since water-power far exceeds human strength, this machine +draws water through its pipes by discs out of a shaft more than one +hundred feet deep. The bottom of the lowest pipe, set in the sump, not +only of this pump but also of the others, is generally enclosed in a +basket made of wicker-work, to prevent wood shavings and other things +being sucked in. (See p. 183.) + +[Illustration 185 (Suction Pumps): A--shaft. B--Bottom pump. C--First +tank. D--Second pump. E--Second tank. F--Third pump. G--Trough. H--The +iron set in the axle. I--First pump rod. K--Second pump rod. L--Third +pump rod. M--First piston rod. N--Second piston rod. O--Third piston +rod. P--Little axles. Q--"Claws."] + +The seventh kind of pump, invented ten years ago, which is the most +ingenious, durable, and useful of all, can be made without much expense. +It is composed of several pumps, which do not, like those last +described, go down into the shaft together, but of which one is below +the other, for if there are three, as is generally the case, the lower +one lifts the water of the sump and pours it out into the first tank; +the second pump lifts again from that tank into a second tank, and the +third pump lifts it into the drain of the tunnel. A wheel fifteen feet +high raises the piston-rods of all these pumps at the same time and +causes them to drop together. The wheel is made to revolve by paddles, +turned by the force of a stream which has been diverted to the mountain. +The spokes of the water-wheel are mortised in an axle six feet long and +one foot thick, each end of which is surrounded by an iron band, but in +one end there is fixed an iron journal; to the other end is attached an +iron like this journal in its posterior part, which is a digit thick and +as wide as the end of the axle itself. Then the iron extends +horizontally, being rounded and about three digits in diameter, for the +length of a foot, and serves as a journal; thence, it bends to a height +of a foot in a curve, like the horn of the moon, after which it again +extends straight out for one foot; thus it comes about that this last +straight portion, as it revolves in an orbit becomes alternately a foot +higher and a foot lower than the first straight part. From this round +iron crank there hangs the first flat pump-rod, for the crank is fixed +in a perforation in the upper end of this flat pump-rod just as the iron +key of the first set of "claws" is fixed into the lower end. In order to +prevent the pump-rod from slipping off it, as it could easily do, and +that it may be taken off when necessary, its opening is wider than the +corresponding part of the crank, and it is fastened on both sides by +iron keys. To prevent friction, the ends of the pump-rods are protected +by iron plates or intervening leathers. This first pump-rod is about +twelve feet long, the other two are twenty-six feet, and each is a palm +wide and three digits thick. The sides of each pump-rod are covered and +protected by iron plates, which are held on by iron screws, so that a +part which has received damage can be repaired. In the "claws" is set a +small round axle, a foot and a half long and two palms thick. The ends +are encircled by iron bands to prevent the iron journals which revolve +in the iron bearings of the wood from slipping out of it.[15] From this +little axle the wooden "claws" extend two feet, with a width and +thickness of six digits; they are three palms distant from each other, +and both the inner and outer sides are covered with iron plates. Two +rounded iron keys two digits thick are immovably fixed into the claws. +The one of these keys perforates the lower end of the first pump-rod, +and the upper end of the second pump-rod which is held fast. The other +key, which is likewise immovable, perforates the iron end of the first +piston-rod, which is bent in a curve and is immovable. Each such +piston-rod is thirteen feet long and three digits thick, and descends +into the first pipe of each pump to such depth that its disc nearly +reaches the valve-box. When it descends into the pipe, the water, +penetrating through the openings of the disc, raises the leather, and +when the piston-rod is raised the water presses down the leather, and +this supports its weight; then the valve closes the box as a door closes +an entrance. The pipes are joined by two iron bands, one palm wide, one +outside the other, but the inner one is sharp all round that it may fit +into each pipe and hold them together. Although at the present time +pipes lack the inner band, still they have nipples by which they are +joined together, for the lower end of the upper one holds the upper end +of the lower one, each being hewn away for a length of seven digits, the +former inside, the latter outside, so that the one can fit into the +other. When the piston-rod descends into the first pipe, that valve +which I have described is closed; when the piston-rod is raised, the +valve is opened so that the water can run in through the perforations. +Each one of such pumps is composed of two lengths of pipe, each of which +is twelve feet long, and the inside diameter is seven digits. The lower +one is placed in the sump of the shaft, or in a tank, and its lower end +is blocked by a round piece of wood, above which there are six +perforations around the pipe through which the water flows into it. The +upper part of the upper pipe has a notch one foot deep and a palm wide, +through which the water flows away into a tank or trough. Each tank is +two feet long and one foot wide and deep. There is the same number of +axles, "claws," and rods of each kind as there are pumps; if there are +three pumps, there are only two tanks, because the sump of the shaft and +the drain of the tunnel take the place of two. The following is the way +this machine draws water from a shaft. The wheel being turned raises the +first pump-rod, and the pump-rod raises the first "claw," and thus also +the second pump-rod, and the first piston-rod; then the second pump-rod +raises the second "claw," and thus the third pump-rod and the second +piston-rod; then the third pump-rod raises the third "claw" and the +third piston-rod, for there hangs no pump-rod from the iron key of +these claws, for it can be of no use in the last pump. In turn, when the +first pump-rod descends, each set of "claws" is lowered, each pump-rod +and each piston-rod. And by this system, at the same time the water is +lifted into the tanks and drained out of them; from the sump at the +bottom of the shaft it is drained out, and it is poured into the trough +of the tunnel. Further, around the main axle there may be placed two +water wheels, if the river supplies enough water to turn them, and from +the back part of each round iron crank, one or two pump-rods can be +hung, each of which can move the piston-rods of three pumps. Lastly, it +is necessary that the shafts from which the water is pumped out in pipes +should be vertical, for as in the case of the hauling machines, all +pumps which have pipes do not draw the water so high if the pipes are +inclined in inclined shafts, as if they are placed vertically in +vertical shafts. + +[Illustration 187 (Suction Pumps): A--Water wheel of upper machine. +B--Its pump. C--Its trough. D--Wheel of lower machine. E--Its pump. +F--Race.] + +If the river does not supply enough water-power to turn the +last-described pump, which happens because of the nature of the locality +or occurs during the summer season when there are daily droughts, a +machine is built with a wheel so low and light that the water of ever so +little a stream can turn it. This water, falling into a race, runs +therefrom on to a second high and heavy wheel of a lower machine, whose +pump lifts the water out of a deep shaft. Since, however, the water of +so small a stream cannot alone revolve the lower water-wheel, the axle +of the latter is turned at the start with a crank worked by two men, but +as soon as it has poured out into a pool the water which has been drawn +up by the pumps, the upper wheel draws up this water by its own pump, +and pours it into the race, from which it flows on to the lower +water-wheel and strikes its buckets. So both this water from the mine, +as well as the water of the stream, being turned down the races on to +that subterranean wheel of the lower machine, turns it, and water is +pumped out of the deeper part of the shaft by means of two or three +pumps.[16] + +[Illustration 189 (Duplex suction Pumps): A--Upper axle. B--Wheel whose +buckets the force of the stream strikes. C--Toothed drum. D--Second +axle. E--Drum composed of rundles. F--Curved round irons. G--Rows of +pumps.] + +If the stream supplies enough water straightway to turn a higher and +heavier water-wheel, then a toothed drum is fixed to the other end of +the axle, and this turns the drum made of rundles on another axle set +below it. To each end of this lower axle there is fitted a crank of +round iron curved like the horns of the moon, of the kind employed in +machines of this description. This machine, since it has rows of pumps +on each side, draws great quantities of water. + +[Illustration 191 (Rag and Chain Pumps): A--Wheel. B--Axle. C--Journals. +D--Pillows. E--Drum. F--Clamps. G--Drawing-chain. H--Timbers. I--Balls. +K--Pipe. L--Race of stream.] + +Of the rag and chain pumps there are six kinds known to us, of which the +first is made as follows: A cave is dug under the surface of earth or in +a tunnel, and timbered on all sides by stout posts and planks, to +prevent either the men from being crushed or the machine from being +broken by its collapse. In this cave, thus timbered, is placed a +water-wheel fitted to an angular axle. The iron journals of the axle +revolve in iron pillows, which are held in timbers of sufficient +strength. The wheel is generally twenty-four feet high, occasionally +thirty, and in no way different from those which are made for grinding +corn, except that it is a little narrower. The axle has on one side a +drum with a groove in the middle of its circumference, to which are +fixed many four-curved iron clamps. In these clamps catch the links of +the chain, which is drawn through the pipes out of the sump, and which +again falls, through a timbered opening, right down to the bottom into +the sump to a balancing drum. There is an iron band around the small +axle of the balancing drum, each journal of which revolves in an iron +bearing fixed to a timber. The chain turning about this drum brings up +the water by the balls through the pipes. Each length of pipe is +encircled and protected by five iron bands, a palm wide and a digit +thick, placed at equal distances from each other; the first band on the +pipe is shared in common with the preceding length of pipe into which it +is fitted, the last band with the succeeding length of pipe which is +fitted into it. Each length of pipe, except the first, is bevelled on +the outer circumference of the upper end to a distance of seven digits +and for a depth of three digits, in order that it may be inserted into +the length of pipe which goes before it; each, except the last, is +reamed out on the inside of the lower end to a like distance, but to the +depth of a palm, that it may be able to take the end of the pipe which +follows. And each length of pipe is fixed with iron clamps to the +timbers of the shaft, that it may remain stationary. Through this +continuous series of pipes, the water is drawn by the balls of the chain +up out of the sump as far as the tunnel, where it flows but into the +drains through an aperture in the highest pipe. The balls which lift the +water are connected by the iron links of the chain, and are six feet +distant from one another; they are made of the hair of a horse's tail +sewn into a covering to prevent it from being pulled out by the iron +clamps on the drum; the balls are of such size that one can be held in +each hand. If this machine is set up on the surface of the earth, the +stream which turns the water-wheel is led away through open-air ditches; +if in a tunnel, the water is led away through the subterranean drains. +The buckets of the water-wheel, when struck by the impact of the stream, +move forward and turn the wheel, together with the drum, whereby the +chain is wound up and the balls expel the water through the pipes. If +the wheel of this machine is twenty-four feet in diameter, it draws +water from a shaft two hundred and ten feet deep; if thirty feet in +diameter, it will draw water from a shaft two hundred and forty feet +deep. But such work requires a stream with greater water-power. + +The next pump has two drums, two rows of pipes and two drawing-chains +whose balls lift out the water; otherwise they are like the last pump. +This pump is usually built when an excessive amount of water flows into +the sump. These two pumps are turned by water-power; indeed, water draws +water. + +The following is the way of indicating the increase or decrease of the +water in an underground sump, whether it is pumped by this rag and chain +pump or by the first pump, or the third, or some other. From a beam +which is as high above the shaft as the sump is deep, is hung a cord, to +one end of which there is fastened a stone, the other end being attached +to a plank. The plank is lowered down by an iron wire fastened to the +other end; when the stone is at the mouth of the shaft the plank is +right down the shaft in the sump, in which water it floats. This plank +is so heavy that it can drag down the wire and its iron clasp and hook, +together with the cord, and thus pull the stone upwards. Thus, as the +water decreases, the plank descends and the stone is raised; on the +contrary, when the water increases the plank rises and the stone is +lowered. When the stone nearly touches the beam, since this indicates +that the water has been exhausted from the sump by the pump, the +overseer in charge of the machine closes the water-race and stops the +water-wheel; when the stone nearly touches the ground at the side of the +shaft, this indicates that the sump is full of water which has again +collected in it, because the water raises the plank and thus the stone +drags back both the rope and the iron wire; then the overseer opens the +water-race, whereupon the water of the stream again strikes the buckets +of the water-wheel and turns the pump. As workmen generally cease from +their labours on the yearly holidays, and sometimes on working days, +and are thus not always near the pump, and as the pump, if necessary, +must continue to draw water all the time, a bell rings aloud +continuously, indicating that this pump, or any other kind, is uninjured +and nothing is preventing its turning. The bell is hung by a cord from a +small wooden axle held in the timbers which stand over the shaft, and a +second long cord whose upper end is fastened to the small axle is +lowered into the shaft; to the lower end of this cord is fastened a +piece of wood; and as often as a cam on the main axle strikes it, so +often does the bell ring and give forth a sound. + +[Illustration 193 (Rag and Chain Pumps): A--Upright axle. B--Toothed +wheel. C--Teeth. D--Horizontal axle. E--Drum which is made of rundles. +F--Second drum. G--Drawing-chain. H--The balls.] + +The third pump of this kind is employed by miners when no river capable +of turning a water-wheel can be diverted, and it is made as follows. +They first dig a chamber and erect strong timbers and planks to prevent +the sides from falling in, which would overwhelm the pump and kill the +men. The roof of the chamber is protected with contiguous timbers, so +arranged that the horses which pull the machine can travel over it. Next +they again set up sixteen beams forty feet long and one foot wide and +thick, joined by clamps at the top and spreading apart at the bottom, +and they fit the lower end of each beam into a separate sill laid flat +on the ground, and join these by a post; thus there is created a +circular area of which the diameter is fifty feet. Through an opening in +the centre of this area there descends an upright square axle, +forty-five feet long and a foot and a half wide and thick; its lower +pivot revolves in a socket in a block laid flat on the ground in the +chamber, and the upper pivot revolves in a bearing in a beam which is +mortised into two beams at the summit beneath the clamps; the lower +pivot is seventeen feet distant from either side of the chamber, _i.e._, +from its front and rear. At the height of a foot above its lower end, +the axle has a toothed wheel, the diameter of which is twenty-two feet. +This wheel is composed of four spokes and eight rim pieces; the spokes +are fifteen feet long and three-quarters of a foot wide and thick[17]; +one end of them is mortised in the axle, the other in the two rims where +they are joined together. These rims are three-quarters of a foot thick +and one foot wide, and from them there rise and project upright teeth +three-quarters of a foot high, half a foot wide, and six digits thick. +These teeth turn a second horizontal axle by means of a drum composed of +twelve rundles, each three feet long and six digits wide and thick. This +drum, being turned, causes the axle to revolve, and around this axle +there is a drum having iron clamps with fourfold curves in which catch +the links of a chain, which draws water through pipes by means of balls. +The iron journals of this horizontal axle revolve on pillows which are +set in the centre of timbers. Above the roof of the chamber there are +mortised into the upright axle the ends of two beams which rise +obliquely; the upper ends of these beams support double cross-beams, +likewise mortised to the axle. In the outer end of each cross-beam there +is mortised a small wooden piece which appears to hang down; in this +wooden piece there is similarly mortised at the lower end a short +board; this has an iron key which engages a chain, and this chain again +a pole-bar. This machine, which draws water from a shaft two hundred and +forty feet deep, is worked by thirty-two horses; eight of them work for +four hours, and then these rest for twelve hours, and the same number +take their place. This kind of machine is employed at the foot of the +Harz[18] mountains and in the neighbourhood. Further, if necessity +arises, several pumps of this kind are often built for the purpose of +mining one vein, but arranged differently in different localities +varying according to the depth. At Schemnitz, in the Carpathian +mountains, there are three pumps, of which the lowest lifts water from +the lowest sump to the first drains, through which it flows into the +second sump; the intermediate one lifts from the second sump to the +second drain, from which it flows into the third sump; and the upper one +lifts it to the drains of the tunnel, through which it flows away. This +system of three machines of this kind is turned by ninety-six horses; +these horses go down to the machines by an inclined shaft, which slopes +and twists like a screw and gradually descends. The lowest of these +machines is set in a deep place, which is distant from the surface of +the ground 660 feet. + +[Illustration 194 (Rag and Chain Pumps): A--Axle. B--Drum. +C--Drawing-chain. D--Balls. E--Clamps.] + +The fourth species of pump belongs to the same genera, and is made as +follows. Two timbers are erected, and in openings in them, the ends of a +barrel revolve. Two or four strong men turn the barrel, that is to say, +one or two pull the cranks, and one or two push them, and in this way +help the others; alternately another two or four men take their place. +The barrel of this machine, just like the horizontal axle of the other +machines, has a drum whose iron clamps catch the links of a +drawing-chain. Thus water is drawn through the pipes by the balls from a +depth of forty-eight feet. Human strength cannot draw water higher than +this, because such very heavy labour exhausts not only men, but even +horses; only water-power can drive continuously a drum of this kind. +Several pumps of this kind, as of the last, are often built for the +purpose of mining on a single vein, but they are arranged differently +for different positions and depths. + +[Illustration 195 (Rag and Chain Pumps): A--Axles. B--Levers. C--Toothed +drum. D--Drum made of rundles. E--Drum in which iron clamps are fixed.] + +The fifth pump of this kind is partly like the third and partly like +the fourth, because it is turned by strong men like the last, and like +the third it has two axles and three drums, though each axle is +horizontal. The journals of each axle are so fitted in the pillows of +the beams that they cannot fly out; the lower axle has a crank at one +end and a toothed drum at the other end; the upper axle has at one end a +drum made of rundles, and at the other end, a drum to which are fixed +iron clamps, in which the links of a chain catch in the same way as +before, and from the same depth, draw water through pipes by means of +balls. This revolving machine is turned by two pairs of men alternately, +for one pair stands working while the other sits taking a rest; while +they are engaged upon the task of turning, one pulls the crank and the +other pushes, and the drums help to make the pump turn more easily. + +[Illustration 197 (Rag and Chain Pumps): A--Axles. B--Wheel which is +turned by treading. C--Toothed wheel. D--Drum made of rundles. E--Drum +to which are fixed iron clamps. F--Second wheel. G--Balls.] + +The sixth pump of this kind likewise has two axles. At one end of the +lower axle is a wheel which is turned by two men treading, this is +twenty-three feet high and four feet wide, so that one man may stand +alongside the other. At the other end of this axle is a toothed wheel. +The upper[19] axle has two drums and one wheel; the first drum is made +of rundles, and to the other there are fixed the iron clamps. The wheel +is like the one on the second machine which is chiefly used for drawing +earth and broken rock out of shafts. The treaders, to prevent themselves +from falling, grasp in their hands poles which are fixed to the inner +sides of the wheel. When they turn this wheel, the toothed drum being +made to revolve, sets in motion the other drum which is made of rundles, +by which means again the links of the chain catch to the cleats of the +third drum and draw water through pipes by means of balls,--from a depth +of sixty-six feet. + +[Illustration 199 (Baling Water): A--Reservoir. B--Race. C, D--Levers. +E, F--Troughs under the water gates. G, H--Double rows of buckets. +I--Axle. K--Larger drum. L--Drawing-chain. M--Bag. N--Hanging cage. +O--Man who directs the machine. P, Q--Men emptying bags.] + +But the largest machine of all those which draw water is the one which +follows. First of all a reservoir is made in a timbered chamber; this +reservoir is eighteen feet long and twelve feet wide and high. Into this +reservoir a stream is diverted through a water-race or through the +tunnel; it has two entrances and the same number of gates. Levers are +fixed to the upper part of these gates, by which they can be raised and +let down again, so that by one way the gates are opened and in the other +way closed. Beneath the openings are two plank troughs which carry the +water flowing from the reservoir, and pour it on to the buckets of the +water-wheel, the impact of which turns the wheel. The shorter trough +carries the water, which strikes the buckets that turn the wheel toward +the reservoir, and the longer trough carries the water which strikes +those buckets that turn the wheel in the opposite direction. The casing +or covering of the wheel is made of joined boards to which strips are +affixed on the inner side. The wheel itself is thirty-six feet in +diameter, and is mortised to an axle, and it has, as I have already +said, two rows of buckets, of which one is set the opposite way to the +other, so that the wheel may be turned toward the reservoir or in the +opposite direction. The axle is square and is thirty-five feet long +and two feet thick and wide. Beyond the wheel, at a distance of six +feet, the axle has four hubs, one foot wide and thick, each one of which +is four feet distant from the next; to these hubs are fixed by iron +nails as many pieces of wood as are necessary to cover the hubs, and, in +order that the wood pieces may fit tight, they are broader on the +outside and narrower on the inside; in this way a drum is made, around +which is wound a chain to whose ends are hooked leather bags. The reason +why a drum of this kind is made, is that the axle may be kept in good +condition, because this drum when it becomes worn away by use can be +repaired easily. Further along the axle, not far from the end, is +another drum one foot broad, projecting two feet on all sides around the +axle. And to this, when occasion demands, a brake is applied forcibly +and holds back the machine; this kind of brake I have explained before. +Near the axle, in place of a hopper, there is a floor with a +considerable slope, having in front of the shaft a width of fifteen feet +and the same at the back; at each side of it there is a stout post +carrying an iron chain which has a large hook. Five men operate this +machine; one lets down the doors which close the reservoir gates, or by +drawing down the levers, opens the water-races; this man, who is the +director of this machine, stands in a hanging cage beside the reservoir. +When one bag has been drawn out nearly as far as the sloping floor, he +closes the water gate in order that the wheel may be stopped; when the +bag has been emptied he opens the other water gate, in order that the +other set of buckets may receive the water and drive the wheel in the +opposite direction. If he cannot close the water-gate quickly enough, +and the water continues to flow, he calls out to his comrade and bids +him raise the brake upon the drum and stop the wheel. Two men +alternately empty the bags, one standing on that part of the floor which +is in front of the shaft, and the other on that part which is at the +back. When the bag has been nearly drawn up--of which fact a certain +link of the chain gives warning--the man who stands on the one part of +the floor, catches a large iron hook in one link of the chain, and pulls +out all the subsequent part of the chain toward the floor, where the bag +is emptied by the other man. The object of this hook is to prevent the +chain, by its own weight, from pulling down the other empty bag, and +thus pulling the whole chain from its axle and dropping it down the +shaft. His comrade in the work, seeing that the bag filled with water +has been nearly drawn out, calls to the director of the machine and bids +him close the water of the tower so that there will be time to empty the +bag; this being emptied, the director of the machine first of all +slightly opens the other water-gate of the tower to allow the end of the +chain, together with the empty bag, to be started into the shaft again, +and then opens entirely the water-gates. When that part of the chain +which has been pulled on to the floor has been wound up again, and has +been let down over the shaft from the drum, he takes out the large hook +which was fastened into a link of the chain. The fifth man stands in a +sort of cross-cut beside the sump, that he may not be hurt, if it should +happen that a link is broken and part of the chain or anything else +should fall down; he guides the bag with a wooden shovel, and fills it +with water if it fails to take in the water spontaneously. In these +days, they sew an iron band into the top of each bag that it may +constantly remain open, and when lowered into the sump may fill itself +with water, and there is no need for a man to act as governor of the +bags. Further, in these days, of those men who stand on the floor the +one empties the bags, and the other closes the gates of the reservoir +and opens them again, and the same man usually fixes the large hook in +the link of the chain. In this way, three men only are employed in +working this machine; or even--since sometimes the one who empties the +bag presses the brake which is raised against the other drum and thus +stops the wheel--two men take upon themselves the whole labour. + +But enough of haulage machines; I will now speak of ventilating +machines. If a shaft is very deep and no tunnel reaches to it, or no +drift from another shaft connects with it, or when a tunnel is of great +length and no shaft reaches to it, then the air does not replenish +itself. In such a case it weighs heavily on the miners, causing them to +breathe with difficulty, and sometimes they are even suffocated, and +burning lamps are also extinguished. There is, therefore, a necessity +for machines which the Greeks call [Greek: pneumatikai] and the Latins +_spiritales_--though they do not give forth any sound--which enable the +miners to breathe easily and carry on their work. + +[Illustration 201 (Windsails for Ventilation): A--Sills. B--Pointed +stakes. C--Cross-beams. D--Upright planks. E--Hollows. F--Winds. +G--Covering disc. H--Shafts. I--Machine without a covering.] + +These devices are of three genera. The first receives and diverts into +the shaft the blowing of the wind, and this genus is divided into three +species, of which the first is as follows. Over the shaft--to which no +tunnel connects--are placed three sills a little longer than the shaft, +the first over the front, the second over the middle, and the third over +the back of the shaft. Their ends have openings, through which pegs, +sharpened at the bottom, are driven deeply into the ground so as to hold +them immovable, in the same way that the sills of the windlass are +fixed. Each of these sills is mortised into each of three cross-beams, +of which one is at the right side of the shaft, the second at the left, +and the third in the middle. To the second sill and the second +cross-beam--each of which is placed over the middle of the shaft--planks +are fixed which are joined in such a manner that the one which precedes +always fits into the groove of the one which follows. In this way four +angles and the same number of intervening hollows are created, which +collect the winds that blow from all directions. The planks are roofed +above with a cover made in a circular shape, and are open below, in +order that the wind may not be diverted upward and escape, but may be +carried downward; and thereby the winds of necessity blow into the +shafts through these four openings. However, there is no need to roof +this kind of machine in those localities in which it can be so placed +that the wind can blow down through its topmost part. + +[Illustration 202 (Windsails for Ventilation): A--Projecting mouth of +conduit. B--Planks fixed to the mouth of the conduit which does not +project.] + +The second machine of this genus turns the blowing wind into a shaft +through a long box-shaped conduit, which is made of as many lengths of +planks, joined together, as the depth of the shaft requires; the joints +are smeared with fat, glutinous clay moistened with water. The mouth of +this conduit either projects out of the shaft to a height of three or +four feet, or it does not project; if it projects, it is shaped like a +rectangular funnel, broader and wider at the top than the conduit +itself, that it may the more easily gather the wind; if it does not +project, it is not broader than the conduit, but planks are fixed to it +away from the direction in which the wind is blowing, which catch the +wind and force it into the conduit. + +[Illustration 203 (Windsails for Ventilation): A--Wooden barrels. +B--Hoops. C--Blow-holes. D--Pipe. E--Table. F--Axle. G--Opening in the +bottom of the barrel. H--Wing.] + +The third of this genus of machine is made of a pipe or pipes and a +barrel. Above the uppermost pipe there is erected a wooden barrel, four +feet high and three feet in diameter, bound with wooden hoops; it has a +square blow-hole always open, which catches the breezes and guides them +down either by a pipe into a conduit or by many pipes into the shaft. To +the top of the upper pipe is attached a circular table as thick as the +bottom of the barrel, but of a little less diameter, so that the barrel +may be turned around on it; the pipe projects out of the table and is +fixed in a round opening in the centre of the bottom of the barrel. To +the end of the pipe a perpendicular axle is fixed which runs through the +centre of the barrel into a hole in the cover, in which it is fastened, +in the same way as at the bottom. Around this fixed axle and the table +on the pipe, the movable barrel is easily turned by a zephyr, or much +more by a wind, which govern the wing on it. This wing is made of thin +boards and fixed to the upper part of the barrel on the side furthest +away from the blow-hole; this, as I have said, is square and always +open. The wind, from whatever quarter of the world it blows, drives the +wing straight toward the opposite direction, in which way the barrel +turns the blow-hole towards the wind itself; the blow-hole receives the +wind, and it is guided down into the shaft by means of the conduit or +pipes. + +[Illustration 204 (Ventilation Fans): A--Drum. B--Box-shaped casing. +C--Blow-hole. D--Second hole. E--Conduit. F--Axle. G--Lever of axle. +H--Rods.] + +The second genus of blowing machine is made with fans, and is likewise +varied and of many forms, for the fans are either fitted to a windlass +barrel or to an axle. If to an axle, they are either contained in a +hollow drum, which is made of two wheels and a number of boards joining +them together, or else in a box-shaped casing. The drum is stationary +and closed on the sides, except for round holes of such size that the +axle may turn in them; it has two square blow-holes, of which the upper +one receives the air, while the lower one empties into the conduit +through which the air is led down the shaft. The ends of the axle, which +project on each side of the drum, are supported by forked posts or +hollowed beams plated with thick iron; one end of the axle has a crank, +while in the other end are fixed four rods with thick heavy ends, so +that they weight the axle, and when turned, make it prone to motion as +it revolves. And so, when the workman turns the axle by the crank, the +fans, the description of which I will give a little later, draw in the +air by the blow-hole, and force it through the other blow-hole which +leads to the conduit, and through this conduit the air penetrates into +the shaft. + +[Illustration 205 (Ventilation Fans): A--Box-shaped casing placed on the +ground. B--Its blow-hole. C--Its axle with fans. D--Crank of the axle. +E--Rods of same. F--Casing set on timbers. G--Sails which the axle has +outside the casing.] + +The one with the box-shaped casing is furnished with just the same +things as the drum, but the drum is far superior to the box; for the +fans so fill the drum that they almost touch it on every side, and drive +into the conduit all the air that has been accumulated; but they cannot +thus fill the box-shaped casing, on account of its angles, into which +the air partly retreats; therefore it cannot be as useful as the drum. +The kind with a box-shaped casing is not only placed on the ground, but +is also set up on timbers like a windmill, and its axle, in place of a +crank, has four sails outside, like the sails of a windmill. When these +are struck by the wind they turn the axle, and in this way its +fans--which are placed within the casing--drive the air through the +blow-hole and the conduit into the shaft. Although this machine has no +need of men whom it is necessary to pay to work the crank, still when +the sky is devoid of wind, as it often is, the machine does not turn, +and it is therefore less suitable than the others for ventilating a +shaft. + +[Illustration 206 (Ventilation Fans): A--Hollow drum. B--Its blow-hole. +C--Axle with fans. D--Drum which is made of rundles. E--Lower axle. +F--Its toothed wheel. G--Water wheel.] + +In the kind where the fans are fixed to an axle, there is generally a +hollow stationary drum at one end of the axle, and on the other end is +fixed a drum made of rundles. This rundle drum is turned by the toothed +wheel of a lower axle, which is itself turned by a wheel whose buckets +receive the impetus of water. If the locality supplies an abundance of +water this machine is most useful, because to turn the crank does not +need men who require pay, and because it forces air without cessation +through the conduit into the shaft. + +[Illustration 207 (Ventilation Fans): A--First kind of fan. B--Second +kind of fan. C--Third kind of fan. D--Quadrangular part of axle. +E--Round part of same. F--Crank.] + +Of the fans which are fixed on to an axle contained in a drum or box, +there are three sorts. The first sort is made of thin boards of such +length and width as the height and width of the drum or box require; the +second sort is made of boards of the same width, but shorter, to which +are bound long thin blades of poplar or some other flexible wood; the +third sort has boards like the last, to which are bound double and +triple rows of goose feathers. This last is less used than the second, +which in turn is less used than the first. The boards of the fan are +mortised into the quadrangular parts of the barrel axle. + +[Illustration 208 (Bellows for mine ventilation): A--Smaller part of +shaft. B--Square conduit. C--Bellows. D--Larger part of shaft.] + +Blowing machines of the third genus, which are no less varied and of no +fewer forms than those of the second genus, are made with bellows, for +by its blasts the shafts and tunnels are not only furnished with air +through conduits or pipes, but they can also be cleared by suction of +their heavy and pestilential vapours. In the latter case, when the +bellows is opened it draws the vapours from the conduits through its +blow-hole and sucks these vapours into itself; in the former case, when +it is compressed, it drives the air through its nozzle into the conduits +or pipes. They are compressed either by a man, or by a horse or by +water-power; if by a man, the lower board of a large bellows is fixed to +the timbers above the conduit which projects out of the shaft, and so +placed that when the blast is blown through the conduit, its nozzle is +set in the conduit. When it is desired to suck out heavy or pestilential +vapours, the blow-hole of the bellows is fitted all round the mouth of +the conduit. Fixed to the upper bellows board is a lever which couples +with another running downward from a little axle, into which it is +mortised so that it may remain immovable; the iron journals of this +little axle revolve in openings of upright posts; and so when the +workman pulls down the lever the upper board of the bellows is raised, +and at the same time the flap of the blow-hole is dragged open by the +force of the wind. If the nozzle of the bellows is enclosed in the +conduit it draws pure air into itself, but if its blow-hole is fitted +all round the mouth of the conduit it exhausts the heavy and +pestilential vapours out of the conduit and thus from the shaft, even if +it is one hundred and twenty feet deep. A stone placed on the upper +board of the bellows depresses it and then the flap of the blow-hole is +closed. The bellows, by the first method, blows fresh air into the +conduit through its nozzle, and by the second method blows out through +the nozzle the heavy and pestilential vapours which have been collected. +In this latter case fresh air enters through the larger part of the +shaft, and the miners getting the benefit of it can sustain their toil. +A certain smaller part of the shaft which forms a kind of estuary, +requires to be partitioned off from the other larger part by +uninterrupted lagging, which reaches from the top of the shaft to the +bottom; through this part the long but narrow conduit reaches down +nearly to the bottom of the shaft. + +[Illustration 209 (Bellows for mine ventilation): A--Tunnel. B--Pipe. +C--Nozzle of double bellows.] + +When no shaft has been sunk to such depth as to meet a tunnel driven far +into a mountain, these machines should be built in such a manner that +the workman can move them about. Close by the drains of the tunnel +through which the water flows away, wooden pipes should be placed and +joined tightly together in such a manner that they can hold the air; +these should reach from the mouth of the tunnel to its furthest end. At +the mouth of the tunnel the bellows should be so placed that through its +nozzle it can blow its accumulated blasts into the pipes or the conduit; +since one blast always drives forward another, they penetrate into the +tunnel and change the air, whereby the miners are enabled to continue +their work. + +[Illustration 211 (Bellows for mine ventilation): A--Machine first +described. B--This workman, treading with his feet, is compressing the +bellows. C--Bellows without nozzles. D--Hole by which heavy vapours or +blasts are blown out. E--Conduits. F--Tunnel. G--Second machine +described. H--Wooden wheel. I--Its steps. K--Bars. L--Hole in same +wheel. M--Pole. N--Third machine described. O--Upright axle. P--Its +toothed drum. Q--Horizontal axle. R--Its drum which is made of rundles.] + +If heavy vapours need to be drawn off from the tunnels, generally three +double or triple bellows, without nozzles and closed in the forepart, +are placed upon benches. A workman compresses them by treading with his +feet, just as persons compress those bellows of the organs which give +out varied and sweet sounds in churches. These heavy vapours are thus +drawn along the air-pipes and through the blow-hole of the lower bellows +board, and are expelled through the blow-hole of the upper bellows board +into the open air, or into some shaft or drift. This blow-hole has a +flap-valve, which the noxious blast opens, as often as it passes out. +Since one volume of air constantly rushes in to take the place of +another which has been drawn out by the bellows, not only is the heavy +air drawn out of a tunnel as great as 1,200 feet long, or even longer, +but also the wholesome air is naturally drawn in through that part of +the tunnel which is open outside the conduits. In this way the air is +changed, and the miners are enabled to carry on the work they have +begun. If machines of this kind had not been invented, it would be +necessary for miners to drive two tunnels into a mountain, and +continually, at every two hundred feet at most, to sink a shaft from the +upper tunnel to the lower one, that the air passing into the one, and +descending by the shafts into the other, would be kept fresh for the +miners; this could not be done without great expense. + +There are two different machines for operating, by means of horses, the +above described bellows. The first of these machines has on its axle a +wooden wheel, the rim of which is covered all the way round by steps; a +horse is kept continually within bars, like those within which horses +are held to be shod with iron, and by treading these steps with its feet +it turns the wheel, together with the axle; the cams on the axle press +down the sweeps which compress the bellows. The way the instrument is +made which raises the bellows again, and also the benches on which the +bellows rest, I will explain more clearly in Book IX. Each bellows, if +it draws heavy vapours out of a tunnel, blows them out of the hole in +the upper board; if they are drawn out of a shaft, it blows them out +through its nozzle. The wheel has a round hole, which is transfixed with +a pole when the machine needs to be stopped. + +The second machine has two axles; the upright one is turned by a horse, +and its toothed drum turns a drum made of rundles on a horizontal axle; +in other respects this machine is like the last. Here, also, the nozzles +of the bellows placed in the conduits blow a blast into the shaft or +tunnel. + +[Illustration 212 (Ventilating with Damp Cloth): A--Tunnel. B--Linen +cloth.] + +In the same way that this last machine can refresh the heavy air of a +shaft or tunnel, so also could the old system of ventilating by the +constant shaking of linen cloths, which Pliny[20] has explained; the air +not only grows heavier with the depth of a shaft, of which fact he has +made mention, but also with the length of a tunnel. + +[Illustration 213 (Descent into Mines): A--Descending into the shaft by +ladders. B--By sitting on a stick. C--By sitting on the dirt. +D--Descending by steps cut in the rock.] + +The climbing machines of miners are ladders, fixed to one side of the +shaft, and these reach either to the tunnel or to the bottom of the +shaft. I need not describe how they are made, because they are used +everywhere, and need not so much skill in their construction as care in +fixing them. However, miners go down into mines not only by the steps of +ladders, but they are also lowered into them while sitting on a stick or +a wicker basket, fastened to the rope of one of the three drawing +machines which I described at first. Further, when the shafts are much +inclined, miners and other workmen sit in the dirt which surrounds their +loins and slide down in the same way that boys do in winter-time when +the water on some hillside has congealed with the cold, and to prevent +themselves from falling, one arm is wound about a rope, the upper end of +which is fastened to a beam at the mouth of the shaft, and the lower end +to a stake fixed in the bottom of the shaft. In these three ways miners +descend into the shafts. A fourth way may be mentioned which is employed +when men and horses go down to the underground machines and come up +again, that is by inclined shafts which are twisted like a screw and +have steps cut in the rock, as I have already described. + +It remains for me to speak of the ailments and accidents of miners, and +of the methods by which they can guard against these, for we should +always devote more care to maintaining our health, that we may freely +perform our bodily functions, than to making profits. Of the illnesses, +some affect the joints, others attack the lungs, some the eyes, and +finally some are fatal to men. + +Where water in shafts is abundant and very cold, it frequently injures +the limbs, for cold is harmful to the sinews. To meet this, miners +should make themselves sufficiently high boots of rawhide, which protect +their legs from the cold water; the man who does not follow this advice +will suffer much ill-health, especially when he reaches old age. On the +other hand, some mines are so dry that they are entirely devoid of +water, and this dryness causes the workmen even greater harm, for the +dust which is stirred and beaten up by digging penetrates into the +windpipe and lungs, and produces difficulty in breathing, and the +disease which the Greeks call [Greek: asthma]. If the dust has corrosive +qualities, it eats away the lungs, and implants consumption in the body; +hence in the mines of the Carpathian Mountains women are found who have +married seven husbands, all of whom this terrible consumption has +carried off to a premature death. At Altenberg in Meissen there is found +in the mines black _pompholyx_, which eats wounds and ulcers to the +bone; this also corrodes iron, for which reason the keys of their sheds +are made of wood. Further, there is a certain kind of _cadmia_[21] which +eats away the feet of the workmen when they have become wet, and +similarly their hands, and injures their lungs and eyes. Therefore, for +their digging they should make for themselves not only boots of +rawhide, but gloves long enough to reach to the elbow, and they should +fasten loose veils over their faces; the dust will then neither be drawn +through these into their windpipes and lungs, nor will it fly into their +eyes. Not dissimilarly, among the Romans[22] the makers of vermilion +took precautions against breathing its fatal dust. + +Stagnant air, both that which remains in a shaft and that which remains +in a tunnel, produces a difficulty in breathing; the remedies for this +evil are the ventilating machines which I have explained above. There is +another illness even more destructive, which soon brings death to men +who work in those shafts or levels or tunnels in which the hard rock is +broken by fire. Here the air is infected with poison, since large and +small veins and seams in the rocks exhale some subtle poison from the +minerals, which is driven out by the fire, and this poison itself is +raised with the smoke not unlike _pompholyx_,[23] which clings to the +upper part of the walls in the works in which ore is smelted. If this +poison cannot escape from the ground, but falls down into the pools and +floats on their surface, it often causes danger, for if at any time the +water is disturbed through a stone or anything else, these fumes rise +again from the pools and thus overcome the men, by being drawn in with +their breath; this is even much worse if the fumes of the fire have not +yet all escaped. The bodies of living creatures who are infected with +this poison generally swell immediately and lose all movement and +feeling, and they die without pain; men even in the act of climbing from +the shafts by the steps of ladders fall back into the shafts when the +poison overtakes them, because their hands do not perform their office, +and seem to them to be round and spherical, and likewise their feet. If +by good fortune the injured ones escape these evils, for a little while +they are pale and look like dead men. At such times, no one should +descend into the mine or into the neighbouring mines, or if he is in +them he should come out quickly. Prudent and skilled miners burn the +piles of wood on Friday, towards evening, and they do not descend into +the shafts nor enter the tunnels again before Monday, and in the +meantime the poisonous fumes pass away. + +There are also times when a reckoning has to be made with Orcus,[24] for +some metalliferous localities, though such are rare, spontaneously +produce poison and exhale pestilential vapour, as is also the case with +some openings in the ore, though these more often contain the noxious +fumes. In the towns of the plains of Bohemia there are some caverns +which, at certain seasons of the year, emit pungent vapours which put +out lights and kill the miners if they linger too long in them. Pliny, +too, has left a record that when wells are sunk, the sulphurous or +aluminous vapours which arise kill the well-diggers, and it is a test of +this danger if a burning lamp which has been let down is extinguished. +In such cases a second well is dug to the right or left, as an +air-shaft, which draws off these noxious vapours. On the plains they +construct bellows which draw up these noxious vapours and remedy this +evil; these I have described before. + +Further, sometimes workmen slipping from the ladders into the shafts +break their arms, legs, or necks, or fall into the sumps and are +drowned; often, indeed, the negligence of the foreman is to blame, for +it is his special work both to fix the ladders so firmly to the timbers +that they cannot break away, and to cover so securely with planks the +sumps at the bottom of the shafts, that the planks cannot be moved nor +the men fall into the water; wherefore the foreman must carefully +execute his own work. Moreover, he must not set the entrance of the +shaft-house toward the north wind, lest in winter the ladders freeze +with cold, for when this happens the men's hands become stiff and +slippery with cold, and cannot perform their office of holding. The men, +too, must be careful that, even if none of these things happen, they do +not fall through their own carelessness. + +Mountains, too, slide down and men are crushed in their fall and perish. +In fact, when in olden days Rammelsberg, in Goslar, sank down, so many +men were crushed in the ruins that in one day, the records tell us, +about 400 women were robbed of their husbands. And eleven years ago, +part of the mountain of Altenberg, which had been excavated, became +loose and sank, and suddenly crushed six miners; it also swallowed up a +hut and one mother and her little boy. But this generally occurs in +those mountains which contain _venae cumulatae_. Therefore, miners +should leave numerous arches under the mountains which need support, or +provide underpinning. Falling pieces of rock also injure their limbs, +and to prevent this from happening, miners should protect the shafts, +tunnels, and drifts. + +The venomous ant which exists in Sardinia is not found in our mines. +This animal is, as Solinus[25] writes, very small and like a spider in +shape; it is called _solifuga_, because it shuns (_fugit_) the light +(_solem_). It is very common in silver mines; it creeps unobserved and +brings destruction upon those who imprudently sit on it. But, as the +same writer tells us, springs of warm and salubrious waters gush out in +certain places, which neutralise the venom inserted by the ants. + +In some of our mines, however, though in very few, there are other +pernicious pests. These are demons of ferocious aspect, about which I +have spoken in my book _De Animantibus Subterraneis_. Demons of this +kind are expelled and put to flight by prayer and fasting.[26] + +Some of these evils, as well as certain other things, are the reason why +pits are occasionally abandoned. But the first and principal cause is +that they do not yield metal, or if, for some fathoms, they do bear +metal they become barren in depth. The second cause is the quantity of +water which flows in; sometimes the miners can neither divert this water +into the tunnels, since tunnels cannot be driven so far into the +mountains, or they cannot draw it out with machines because the shafts +are too deep; or if they could draw it out with machines, they do not +use them, the reason undoubtedly being that the expenditure is greater +than the profits of a moderately poor vein. The third cause is the +noxious air, which the owners sometimes cannot overcome either by skill +or expenditure, for which reason the digging is sometimes abandoned, not +only of shafts, but also of tunnels. The fourth cause is the poison +produced in particular places, if it is not in our power either +completely to remove it or to moderate its effects. This is the reason +why the caverns in the Plain known as Laurentius[27] used not to be +worked, though they were not deficient in silver. The fifth cause are +the fierce and murderous demons, for if they cannot be expelled, no one +escapes from them. The sixth cause is that the underpinnings become +loosened and collapse, and a fall of the mountain usually follows; the +underpinnings are then only restored when the vein is very rich in +metal. The seventh cause is military operations. Shafts and tunnels +should not be re-opened unless we are quite certain of the reasons why +the miners have deserted them, because we ought not to believe that our +ancestors were so indolent and spiritless as to desert mines which could +have been carried on with profit. Indeed, in our own days, not a few +miners, persuaded by old women's tales, have re-opened deserted shafts +and lost their time and trouble. Therefore, to prevent future +generations from being led to act in such a way, it is advisable to set +down in writing the reason why the digging of each shaft or tunnel has +been abandoned, just as it is agreed was once done at Freiberg, when the +shafts were deserted on account of the great inrush of water. + + END OF BOOK VI. + + +FOOTNOTES: + +[1] This Book is devoted in the main to winding, ventilating, and +pumping machinery. Their mechanical principles are very old. The block +and pulley, the windlass, the use of water-wheels, the transmission of +power through shafts and gear-wheels, chain-pumps, piston-pumps with +valves, were all known to the Greeks and Romans, and possibly earlier. +Machines involving these principles were described by Ctesibius, an +Alexandrian of 250 B.C., by Archimedes (287-212 B.C.), and by Vitruvius +(1st Century B.C.) As to how far these machines were applied to mining +by the Ancients we have but little evidence, and this largely in +connection with handling water. Diodorus Siculus (1st Century B.C.) +referring to the Spanish mines, says (Book V.): "Sometimes at great +depths they meet great rivers underground, but by art give check to the +violence of the streams, for by cutting trenches they divert the +current, and being sure to gain what they aim at when they have begun, +they never leave off till they have finished it. And they admirably pump +out the water with those instruments called Egyptian pumps, invented by +Archimedes, the Syracusan, when he was in Egypt. By these, with constant +pumping by turns they throw up the water to the mouth of the pit and +thus drain the mine; for this engine is so ingeniously contrived that a +vast quantity of water is strangely and with little labour cast out." + +Strabo (63 B.C.-24 A.D., III., 2, 9), also referring to Spanish mines, +quoting from Posidonius (about 100 B.C.), says: "He compares with these +(the Athenians) the activity and diligence of the Turdetani, who are in +the habit of cutting tortuous and deep tunnels, and draining the streams +which they frequently encounter by means of Egyptian screws." +(Hamilton's Tran., Vol. I., p. 221). The "Egyptian screw" was +Archimedes' screw, and was thus called because much used by the +Egyptians for irrigation. Pliny (XXXIII., 31) also says, in speaking of +the Spanish silver-lead mines: "The mountain has been excavated for a +distance of 1,500 paces, and along this distance there are +water-carriers standing by torch-light night and day steadily baling the +water (thus) making quite a river." The re-opening of the mines at Rio +Tinto in the middle of the 18th Century disclosed old Roman stopes, in +which were found several water-wheels. These were about 15 feet in +diameter, lifting the water by the reverse arrangement to an overshot +water-wheel. A wooden Archimedian screw was also found in the +neighbourhood. (Nash, The Rio Tinto Mine, its History and Romance, +London, 1904). + +Until early in the 18th Century, water formed the limiting factor in the +depth of mines. To the great devotion to this water problem we owe the +invention of the steam engine. In 1705 Newcomen--no doubt inspired by +Savery's unsuccessful attempt--invented his engine, and installed the +first one on a colliery at Wolverhampton, in Staffordshire. With its +success, a new era was opened to the miner, to be yet further extended +by Watt's improvements sixty years later. It should be a matter of +satisfaction to mining engineers that not only was the steam engine the +handiwork of their profession, but that another mining engineer, +Stephenson, in his effort to further the advance of his calling, +invented the locomotive. + +[2] While these particular tools serve the same purpose as the "gad" and +the "moil," the latter are not fitted with handles, and we have, +therefore, not felt justified in adopting these terms, but have given a +literal rendering of the Latin. + +The Latin and old German terms for these tools were:-- + + First Iron tool = _Ferramentum primum_ = _Bergeisen_. + Second " = " _secundum_ = _Rutzeisen_. + Third " = " _tertium_ = _Sumpffeisen_. + Fourth " = " _quartum_ = _Fimmel_. + Wedge = _Cuneus_ = _Keil_. + Iron block = _Lamina_ = _Plôtz_. + Iron plate = _Bractea_ = _Feder_. + +The German words obviously had local value and do not bear translation +literally. + +[3] One _metreta_, a Greek measure, equalled about nine English gallons, +and a _congius_ contained about six pints. + +[4] _Ingestores_. This is a case of Agricola coining a name for workmen +from the work, the term being derived from _ingero_, to pour or to throw +in, used in the previous clause--hence the "reason." See p. xxxi. + +[5] _Cisium_. A two-wheeled cart. In the preface Agricola gives this as +an example of his intended adaptations. See p. xxxi. + +[6] _Canis_. The Germans in Agricola's time called a truck a _hundt_--a +hound. + +[7] _Alveus_,--"Tray." The Spanish term _batea_ has been so generally +adopted into the mining vocabulary for a wooden bowl for these purposes, +that we introduce it here. + +[8] Pliny (XXXIII., 21). "The fragments are carried on workmen's +shoulders; night and day each passes the material to his neighbour, only +the last of them seeing the daylight." + +[10] _Harpago_,--A "grapple" or "hook." + +[11] Ancient Noricum covered the region of modern Tyrol, with parts of +Bavaria, Salzburg, etc. + +[12] _Machina quae pilis aquas haurit_. "Machine which draws water with +balls." This apparatus is identical with the Cornish "rag and chain +pump" of the same period, and we have therefore adopted that term. + +[13] A _congius_ contained about six pints. + +[14] Vitruvius (X., 9). "But if the water is to be supplied to still +higher places, a double chain of iron is made to revolve on the axis of +the wheel, long enough to reach to the lower level. This is furnished +with brazen buckets, each holding about a _congius_. Then by turning the +wheel, the chain also turns upon the axis and brings the buckets to the +top thereof, on passing which they are inverted and pour into the +conduits the water they have raised." + +[15] This description certainly does not correspond in every particular +with the illustration. + +[16] There is a certain deficiency in the hydraulics of this machine. + +[17] The dimensions given in this description for the various members do +not tally. + +[18] _Melibocian_,--the Harz. + +[19] In the original text this is given as "lower," and appears to be an +error. + +[20] Pliny (XXXI, 28). "In deep wells, the occurrence of _sulphurata_ or +_aluminosa_ vapor is fatal to the diggers. The presence of this peril is +shown if a lighted lamp let down into the well is extinguished. If so, +other wells are sunk to the right and left, which carry off these +noxious gases. Apart from these evils, the air itself becomes noxious +with depth, which can be remedied by constantly shaking linen cloths, +thus setting the air in motion." + +[21] This is given in the German translation as _kobelt_. The _kobelt_ +(or _cobaltum_ of Agricola) was probably arsenical-cobalt, a mineral +common in the Saxon mines. The origin of the application of the word +cobalt to a mineral appears to lie in the German word for the gnomes and +goblins (_kobelts_) so universal to Saxon miners' imaginations,--this +word in turn probably being derived from the Greek _cobali_ (mimes). The +suffering described above seems to have been associated with the +malevolence of demons, and later the word for these demons was attached +to this disagreeable ore. A quaint series of mining "sermons," by Johann +Mathesius, entitled _Sarepta oder Bergpostill_, Nürnberg, 1562, contains +the following passage (p. 154) which bears out this view. We retain the +original and varied spelling of cobalt and also add another view of +Mathesius, involving an experience of Solomon and Hiram of Tyre with +some mines containing cobalt. + +"Sometimes, however, from dry hard veins a certain black, greenish, grey +or ash-coloured earth is dug out, often containing good ore, and this +mineral being burnt gives strong fumes and is extracted like 'tutty.' It +is called _cadmia fossilis_. You miners call it _cobelt_. Germans call +the Black Devil and the old Devil's furies, old and black _cobel_, who +injure people and their cattle with their witchcrafts. Now the Devil is +a wicked, malicious spirit, who shoots his poisoned darts into the +hearts of men, as sorcerers and witches shoot at the limbs of cattle and +men, and work much evil and mischief with _cobalt_ or _hipomane_ or +horses' poison. After quicksilver and _rotgültigen_ ore, are _cobalt_ +and _wismuth_ fumes; these are the most poisonous of the metals, and +with them one can kill flies, mice, cattle, birds, and men. So, fresh +_cobalt_ and _kisswasser_ (vitriol?) devour the hands and feet of +miners, and the dust and fumes of _cobalt_ kill many mining people and +workpeople who do much work among the fumes of the smelters. Whether or +not the Devil and his hellish crew gave their name to _cobelt_, or +_kobelt_, nevertheless, _cobelt_ is a poisonous and injurious metal even +if it contains silver. I find in I. Kings 9, the word _Cabul_. When +Solomon presented twenty towns in Galilee to the King of Tyre, Hiram +visited them first, and would not have them, and said the land was well +named _Cabul_ as Joshua had christened it. It is certain from Joshua +that these twenty towns lay in the Kingdom of Aser, not far from our +_Sarepta_, and that there had been iron and copper mines there, as Moses +says in another place. Inasmuch, then, as these twenty places were +mining towns, and _cobelt_ is a metal, it appears quite likely that the +mineral took its name from the land of Cabul. History and circumstances +bear out the theory that Hiram was an excellent and experienced miner, +who obtained much gold from Ophir, with which he honoured Solomon. +Therefore, the Great King wished to show his gratitude to his good +neighbour by honouring a miner with mining towns. But because the King +of Tyre was skilled in mines, he first inspected the new mines, and saw +that they only produced poor metal and much wild _cobelt_ ore, therefore +he preferred to find his gold by digging the gold and silver in India +rather than by getting it by the _cobelt_ veins and ore. For truly, +_cobelt_ ores are injurious, and are usually so embedded in other ore +that they rob them in the fire and consume (_madtet und frist_) much +lead before the silver is extracted, and when this happens it is +especially _speysig_. Therefore Hiram made a good reckoning as to the +mines and would not undertake all the expense of working and smelting, +and so returned Solomon the twenty towns." + +[22] Pliny (XXXIII, 40). "Those employed in the works preparing +vermilion, cover their faces with a bladder-skin, that they may not +inhale the pernicious powder, yet they can see through the skin." + +[23] _Pompholyx_ was a furnace deposit, usually mostly zinc oxide, but +often containing arsenical oxide, and to this latter quality this +reference probably applies. The symptoms mentioned later in the text +amply indicate arsenical poisoning, of which a sort of spherical effect +on the hands is characteristic. See also note on p. 112 for discussion +of "corrosive" _cadmia_; further information on _pompholyx_ is given in +Note 26, p. 394. + +[24] Orcus, the god of the infernal regions,--otherwise Pluto. + +[25] Caius Julius Solinus was an unreliable Roman Grammarian of the 3rd +Century. There is much difference of opinion as to the precise animal +meant by _solifuga_. The word is variously spelled _solipugus, solpugus, +solipuga, solipunga_, etc., and is mentioned by Pliny (VIII., 43), and +other ancient authors all apparently meaning a venomous insect, either +an ant or a spider. The term in later times indicated a scorpion. + +[26] The presence of demons or gnomes in the mines was so general a +belief that Agricola fully accepted it. This is more remarkable, in view +of our author's very general scepticism regarding the supernatural. He, +however, does not classify them all as bad--some being distinctly +helpful. The description of gnomes of kindly intent, which is contained +in the last paragraph in _De Animantibus_ is of interest:-- + +"Then there are the gentle kind which the Germans as well as the Greeks +call cobalos, because they mimic men. They appear to laugh with glee and +pretend to do much, but really do nothing. They are called little +miners, because of their dwarfish stature, which is about two feet. They +are venerable looking and are clothed like miners in a filleted garment +with a leather apron about their loins. This kind does not often trouble +the miners, but they idle about in the shafts and tunnels and really do +nothing, although they pretend to be busy in all kinds of labour, +sometimes digging ore, and sometimes putting into buckets that which has +been dug. Sometimes they throw pebbles at the workmen, but they rarely +injure them unless the workmen first ridicule or curse them. They are +not very dissimilar to Goblins, which occasionally appear to men when +they go to or from their day's work, or when they attend their cattle. +Because they generally appear benign to men, the Germans call them +_guteli_. Those called _trulli_, which take the form of women as well as +men, actually enter the service of some people, especially the _Suions_. +The mining gnomes are especially active in the workings where metal has +already been found, or where there are hopes of discovering it, because +of which they do not discourage the miners, but on the contrary +stimulate them and cause them to labour more vigorously." + +The German miners were not alone in such beliefs, for miners generally +accepted them--even to-day the faith in "knockers" has not entirely +disappeared from Cornwall. Neither the sea nor the forest so lends +itself to the substantiation of the supernatural as does the mine. The +dead darkness, in which the miners' lamps serve only to distort every +shape, the uncanny noises of restless rocks whose support has been +undermined, the approach of danger and death without warning, the sudden +vanishing or discovery of good fortune, all yield a thousand +corroborations to minds long steeped in ignorance and prepared for the +miraculous through religious teaching. + +[27] The Plains of Laurentius extend from the mouth of the Tiber +southward--say twenty miles south of Rome. What Agricola's authority was +for silver mines in this region we cannot discover. This may, however, +refer to the lead-silver district of the Attic Peninsula, Laurion being +sometimes Latinized as _Laurium_ or _Laurius_. + + + + +BOOK VII. + + +Since the Sixth Book has described the iron tools, the vessels and the +machines used in mines, this Book will describe the methods of +assaying[1] ores; because it is desirable to first test them in order +that the material mined may be advantageously smelted, or that the dross +may be purged away and the metal made pure. Although writers have +mentioned such tests, yet none of them have set down the directions for +performing them, wherefore it is no wonder that those who come later +have written nothing on the subject. By tests of this kind miners can +determine with certainty whether ores contain any metal in them or not; +or if it has already been indicated that the ore contains one or more +metals, the tests show whether it is much or little; the miners also +ascertain by such tests the method by which the metal can be separated +from that part of the ore devoid of it; and further, by these tests, +they determine that part in which there is much metal from that part in +which there is little. Unless these tests have been carefully applied +before the metals are melted out, the ore cannot be smelted without +great loss to the owners, for the parts which do not easily melt in the +fire carry the metals off with them or consume them. In the last case, +they pass off with the fumes; in the other case they are mixed with the +slag and furnace accretions, and in such event the owners lose the +labour which they have spent in preparing the furnaces and the +crucibles, and further, it is necessary for them to incur fresh +expenditure for fluxes and other things. Metals, when they have been +melted out, are usually assayed in order that we may ascertain what +proportion of silver is in a _centumpondium_ of copper or lead, or what +quantity of gold is in one _libra_ of silver; and, on the other hand, +what proportion of copper or lead is contained in a _centumpondium_ of +silver, or what quantity of silver is contained in one _libra_ of gold. +And from this we can calculate whether it will be worth while to +separate the precious metals from the base metals, or not. Further, a +test of this kind shows whether coins are good or are debased; and +readily detects silver, if the coiners have mixed more than is lawful +with the gold; or copper, if the coiners have alloyed with the gold or +silver more of it than is allowable. I will explain all these methods +with the utmost care that I can. + +The method of assaying ore used by mining people, differs from smelting +only by the small amount of material used. Inasmuch as, by smelting a +small quantity, they learn whether the smelting of a large quantity +will compensate them for their expenditure; hence, if they are not +particular to employ assays, they may, as I have already said, sometimes +smelt the metal from the ore with a loss or sometimes without any +profit; for they can assay the ore at a very small expense, and smelt +it only at a great expense. Both processes, however, are carried out in +the same way, for just as we assay ore in a little furnace, so do we +smelt it in the large furnace. Also in both cases charcoal and not wood +is burned. Moreover, in the crucible when metals are tested, be they +gold, silver, copper, or lead, they are mixed in precisely the same way +as they are mixed in the blast furnace when they are smelted. Further, +those who assay ores with fire, either pour out the metal in a liquid +state, or, when it has cooled, break the crucible and clean the metal +from slag; and in the same way the smelter, as soon as the metal flows +from the furnace into the forehearth, pours in cold water and takes the +slag from the metal with a hooked bar. Finally, in the same way that +gold and silver are separated from lead in a cupel, so also are they +separated in the cupellation furnace. + +It is necessary that the assayer who is testing ore or metals should be +prepared and instructed in all things necessary in assaying, and that he +should close the doors of the room in which the assay furnace stands, +lest anyone coming at an inopportune moment might disturb his thoughts +when they are intent on the work. It is also necessary for him to place +his balances in a case, so that when he weighs the little buttons of +metal the scales may not be agitated by a draught of air, for that is a +hindrance to his work. + +[Illustration 223a (Muffle Furnace): Round assay furnace.] + +[Illustration 223b (Muffle Furnace): Rectangular assay furnace.] + +[Illustration 224 (Muffle Assay Furnace): A--Openings in the plate. +B--Part of plate which projects beyond the furnace.] + +Now I will describe the different things which are necessary in +assaying, beginning with the assay furnace, of which one differs from +another in shape, material, and the place in which it is set. In shape, +they may be round or rectangular, the latter shape being more suited to +assaying ores. The materials of the assay furnaces differ, in that one +is made of bricks, another of iron, and certain ones of clay. The one of +bricks is built on a chimney-hearth which is three and a half feet high; +the iron one is placed in the same position, and also the one of clay. +The brick one is a cubit high, a foot wide on the inside, and one foot +two digits long; at a point five digits above the hearth--which is +usually the thickness of an unbaked[2] brick--an iron plate is laid, and +smeared over with lute on the upper side to prevent it from being +injured by the fire; in front of the furnace above the plate is a mouth +a palm high, five digits wide, and rounded at the top. The iron plate +has three openings which are one digit wide and three digits long, one +is at each side and the third at the back; through them sometimes the +ash falls from the burning charcoal, and sometimes the draught blows +through the chamber which is below the iron plate, and stimulates the +fire. For this reason this furnace when used by metallurgists is named +from assaying, but when used by the alchemists it is named from the +wind[3]. The part of the iron plate which projects from the furnace is +generally three-quarters of a palm long and a palm wide; small pieces +of charcoal, after being laid thereon, can be placed quickly in the +furnace through its mouth with a pair of tongs, or again, if necessary, +can be taken out of the furnace and laid there. + +The iron assay furnace is made of four iron bars a foot and a half high; +which at the bottom are bent outward and broadened a short distance to +enable them to stand more firmly; the front part of the furnace is made +from two of these bars, and the back part from two of them; to these +bars on both sides are joined and welded three iron cross-bars, the +first at a height of a palm from the bottom, the second at a height of a +foot, and the third at the top. The upright bars are perforated at that +point where the side cross-bars are joined to them, in order that three +similar iron bars on the remaining sides can be engaged in them; thus +there are twelve cross-bars, which make three stages at unequal +intervals. At the lower stage, the upright bars are distant from each +other one foot and five digits; and at the middle stage the front is +distant from the back three palms and one digit, and the sides are +distant from each other three palms and as many digits; at the highest +stage from the front to the back there is a distance of two palms, and +between the sides three palms, so that in this way the furnace becomes +narrower at the top. Furthermore, an iron rod, bent to the shape of the +mouth, is set into the lowest bar of the front; this mouth, just like +that of the brick furnace, is a palm high and five digits wide. Then the +front cross-bar of the lower stage is perforated on each side of the +mouth, and likewise the back one; through these perforations there pass +two iron rods, thus making altogether four bars in the lower stage, and +these support an iron plate smeared with lute; part of this plate also +projects outside the furnace. The outside of the furnace from the lower +stage to the upper, is covered with iron plates, which are bound to the +bars by iron wires, and smeared with lute to enable them to bear the +heat of the fire as long as possible. + +As for the clay furnace, it must be made of fat, thick clay, medium so +far as relates to its softness or hardness. This furnace has exactly the +same height as the iron one, and its base is made of two earthenware +tiles, one foot and three palms long and one foot and one palm wide. +Each side of the fore part of both tiles is gradually cut away for the +length of a palm, so that they are half a foot and a digit wide, which +part projects from the furnace; the tiles are about a digit and a half +thick. The walls are similarly of clay, and are set on the lower tiles +at a distance of a digit from the edge, and support the upper tiles; the +walls are three digits high and have four openings, each of which is +about three digits high; those of the back part and of each side are +five digits wide, and of the front, a palm and a half wide, to enable +the freshly made cupels to be conveniently placed on the hearth, when it +has been thoroughly warmed, that they may be dried there. Both tiles are +bound on the outer edge with iron wire, pressed into them, so that they +will be less easily broken; and the tiles, not unlike the iron +bed-plate, have three openings three digits long and a digit wide, in +order that when the upper one on account of the heat of the fire or for +some other reason has become damaged, the lower one may be exchanged and +take its place. Through these holes, the ashes from the burning +charcoal, as I have stated, fall down, and air blows into the furnace +after passing through the openings in the walls of the chamber. The +furnace is rectangular, and inside at the lower part it is three palms +and one digit wide and three palms and as many digits long. At the upper +part it is two palms and three digits wide, so that it also grows +narrower; it is one foot high; in the middle of the back it is cut out +at the bottom in the shape of a semicircle, of half a digit radius. Not +unlike the furnace before described, it has in its forepart a mouth +which is rounded at the top, one palm high and a palm and a digit wide. +Its door is also made of clay, and this has a window and a handle; even +the lid of the furnace which is made of clay has its own handle, +fastened on with iron wire. The outer parts and sides of this furnace +are bound with iron wires, which are usually pressed in, in the shape of +triangles. The brick furnaces must remain stationary; the clay and iron +ones can be carried from one place to another. Those of brick can be +prepared more quickly, while those of iron are more lasting, and those +of clay are more suitable. Assayers also make temporary furnaces in +another way; they stand three bricks on a hearth, one on each side and a +third one at the back, the forepart lies open to the draught, and on +these bricks is placed an iron plate, upon which they again stand three +bricks, which hold and retain the charcoal. + +The setting of one furnace differs from another, in that some are placed +higher and others lower; that one is placed higher, in which the man who +is assaying the ore or metals introduces the scorifier through the mouth +with the tongs; that one is placed lower, into which he introduces the +crucible through its open top. + +[Illustration 227 (Crucible Assay Furnace): A--Iron hoop. B--Double +bellows. C--Its nozzle. D--Lever.] + +In some cases the assayer uses an iron hoop[4] in place of a furnace; +this is placed upon the hearth of a chimney, the lower edge being daubed +with lute to prevent the blast of the bellows from escaping under it. If +the blast is given slowly, the ore will be smelted and the copper will +melt in the triangular crucible, which is placed in it and taken away +again with the tongs. The hoop is two palms high and half a digit thick; +its diameter is generally one foot and one palm, and where the blast +from the bellows enters into it, it is notched out. The bellows is a +double one, such as goldworkers use, and sometimes smiths. In the middle +of the bellows there is a board in which there is an air-hole, five +digits wide and seven long, covered by a little flap which is fastened +over the air-hole on the lower side of the board; this flap is of equal +length and width. The bellows, without its head, is three feet long, and +at the back is one foot and one palm wide and somewhat rounded, and it +is three palms wide at the head; the head itself is three palms long and +two palms and a digit wide at the part where it joins the boards, then +it gradually becomes narrower. The nozzle, of which there is only one, +is one foot and two digits long; this nozzle, and one-half of the head +in which the nozzle is fixed, are placed in an opening of the wall, this +being one foot and one palm thick; it reaches only to the iron hoop on +the hearth, for it does not project beyond the wall. The hide of the +bellows is fixed to the bellows-boards with its own peculiar kind of +iron nails. It joins both bellows-boards to the head, and over it there +are cross strips of hide fixed to the bellows-boards with broad-headed +nails, and similarly fixed to the head. The middle board of the bellows +rests on an iron bar, to which it is fastened with iron nails clinched +on both ends, so that it cannot move; the iron bar is fixed between two +upright posts, through which it penetrates. Higher up on these upright +posts there is a wooden axle, with iron journals which revolve in the +holes in the posts. In the middle of this axle there is mortised a +lever, fixed with iron nails to prevent it from flying out; the lever is +five and a half feet long, and its posterior end is engaged in the iron +ring of an iron rod which reaches to the "tail" of the lowest +bellows-board, and there engages another similar ring. And so when the +workman pulls down the lever, the lower part of the bellows is raised +and drives the wind into the nozzle; then the wind, penetrating through +the hole in the middle bellows-board, which is called the air-hole, +lifts up the upper part of the bellows, upon whose upper board is a +piece of lead, heavy enough to press down that part of the bellows +again, and this being pressed down blows a blast through the nozzle. +This is the principle of the double bellows, which is peculiar to the +iron hoop where are placed the triangular crucibles in which copper ore +is smelted and copper is melted. + +[Illustration 228 (Muffles): A--Broad little windows of muffle. +B--Narrow ones. C--Openings in the back thereof.] + +I have spoken of the furnaces and the iron hoop; I will now speak of the +muffles and the crucibles. The muffle is made of clay, in the shape of +an inverted gutter tile; it covers the scorifiers, lest coal dust fall +into them and interfere with the assay. It is a palm and a half broad, +and the height, which corresponds with the mouth of the furnace, is +generally a palm, and it is nearly as long as the furnace; only at the +front end does it touch the mouth of the furnace, everywhere else on the +sides and at the back there is a space of three digits, to allow the +charcoal to lie in the open space between it and the furnace. The muffle +is as thick as a fairly thick earthen jar; its upper part is entire; the +back has two little windows, and each side has two or three or even +four, through which the heat passes into the scorifiers and melts the +ore. In place of little windows, some muffles have small holes, ten in +the back and more on each side. Moreover, in the back below the little +windows, or small holes, there are cut away three semi-circular notches +half a digit high, and on each side there are four. The back of the +muffle is generally a little lower than the front. + +[Illustration 229 (Containers): A--Scorifier. B--Triangular crucible. +C--Cupel.] + +The crucibles differ in the materials from which they are made, because +they are made of either clay or ashes; and those of clay, which we also +call "earthen," differ in shape and size. Some are made in the shape of +a moderately thick salver (scorifiers), three digits wide, and of a +capacity of an _uncia_ measure; in these the ore mixed with fluxes is +melted, and they are used by those who assay gold or silver ore. Some +are triangular and much thicker and more capacious, holding five, or +six, or even more _unciae_; in these copper is melted, so that it can be +poured out, expanded, and tested with fire, and in these copper ore is +usually melted. + +The cupels are made of ashes; like the preceding scorifiers they are +tray-shaped, and their lower part is very thick but their capacity is +less. In these lead is separated from silver, and by them assays are +concluded. Inasmuch as the assayers themselves make the cupels, +something must be said about the material from which they are made, and +the method of making them. Some make them out of all kinds of ordinary +ashes; these are not good, because ashes of this kind contain a certain +amount of fat, whereby such cupels are easily broken when they are hot. +Others make them likewise out of any kind of ashes which have been +previously leached; of this kind are the ashes into which warm water has +been infused for the purpose of making lye. These ashes, after being +dried in the sun or a furnace, are sifted in a hair sieve; and although +warm water washes away the fat from the ashes, still the cupels which +are made from such ashes are not very good because they often contain +charcoal dust, sand, and pebbles. Some make them in the same way out of +any kind of ashes, but first of all pour water into the ashes and remove +the scum which floats thereon; then, after it has become clear, they +pour away the water, and dry the ashes; they then sift them and make the +cupels from them. These, indeed, are good, but not of the best quality, +because ashes of this kind are also not devoid of small pebbles and +sand. To enable cupels of the best quality to be made, all the +impurities must be removed from the ashes. These impurities are of two +kinds; the one sort light, to which class belong charcoal dust and fatty +material and other things which float in water, the other sort heavy, +such as small stones, fine sand, and any other materials which settle in +the bottom of a vessel. Therefore, first of all, water should be poured +into the ashes and the light impurities removed; then the ashes should +be kneaded with the hands, so that they will become properly mixed with +the water. When the water has become muddy and turbid, it should be +poured into a second vessel. In this way the small stones and fine sand, +or any other heavy substance which may be there, remain in the first +vessel, and should be thrown away. When all the ashes have settled in +this second vessel, which will be shown if the water has become clear +and does not taste of the flavour of lye, the water should be thrown +away, and the ashes which have settled in the vessel should be dried in +the sun or in a furnace. This material is suitable for the cupels, +especially if it is the ash of beech wood or other wood which has a +small annual growth; those ashes made from twigs and limbs of vines, +which have rapid annual growth, are not so good, for the cupels made +from them, since they are not sufficiently dry, frequently crack and +break in the fire and absorb the metals. If ashes of beech or similar +wood are not to be had, the assayer makes little balls of such ashes as +he can get, after they have been cleared of impurities in the manner +before described, and puts them in a baker's or potter's oven to burn, +and from these the cupels are made, because the fire consumes whatever +fat or damp there may be. As to all kinds of ashes, the older they are +the better, for it is necessary that they should have the greatest +possible dryness. For this reason ashes obtained from burned bones, +especially from the bones of the heads of animals, are the most suitable +for cupels, as are also those ashes obtained from the horns of deer and +the spines of fishes. Lastly, some take the ashes which are obtained +from burnt scrapings of leather, when the tanners scrape the hides to +clear them from hair. Some prefer to use compounds, that one being +recommended which has one and a half parts of ashes from the bones of +animals or the spines of fishes, and one part of beech ashes, and half a +part of ashes of burnt hide scrapings. From this mixture good cupels are +made, though far better ones are obtained from equal portions of ashes +of burnt hide scrapings, ashes of the bones of heads of sheep and +calves, and ashes of deer horns. But the best of all are produced from +deer horns alone, burnt to powder; this kind, by reason of its extreme +dryness, absorbs metals least of all. Assayers of our own day, however, +generally make the cupels from beech ashes. These ashes, after being +prepared in the manner just described, are first of all sprinkled with +beer or water, to make them stick together, and are then ground in a +small mortar. They are ground again after being mixed with the ashes +obtained from the skulls of beasts or from the spines of fishes; the +more the ashes are ground the better they are. Some rub bricks and +sprinkle the dust so obtained, after sifting it, into the beech ashes, +for dust of this kind does not allow the hearth-lead to absorb the gold +or silver by eating away the cupels. Others, to guard against the same +thing, moisten the cupels with white of egg after they have been made, +and when they have been dried in the sun, again crush them; especially +if they want to assay in it an ore of copper which contains iron. Some +moisten the ashes again and again with cow's milk, and dry them, and +grind them in a small mortar, and then mould the cupels. In the works in +which silver is separated from copper, they make cupels from two parts +of the ashes of the crucible of the cupellation furnace, for these ashes +are very dry, and from one part of bone-ash. Cupels which have been made +in these ways also need to be placed in the sun or in a furnace; +afterward, in whatever way they have been made, they must be kept a long +time in dry places, for the older they are, the dryer and better they +are. + +[Illustration 231 (Cupel Moulds and Pestles): A--Little mould. +B--Inverted mould. C--Pestle. D--Its knob. E--Second pestle.] + +Not only potters, but also the assayers themselves, make scorifiers and +triangular crucibles. They make them out of fatty clay, which is dry[5], +and neither hard nor soft. With this clay they mix the dust of old +broken crucibles, or of burnt and worn bricks; then they knead with a +pestle the clay thus mixed with dust, and then dry it. As to these +crucibles, the older they are, the dryer and better they are. The +moulds in which the cupels are moulded are of two kinds, that is, a +smaller size and a larger size. In the smaller ones are made the cupels +in which silver or gold is purged from the lead which has absorbed it; +in the larger ones are made cupels in which silver is separated from +copper and lead. Both moulds are made out of brass and have no bottom, +in order that the cupels can be taken out of them whole. The pestles +also are of two kinds, smaller and larger, each likewise of brass, and +from the lower end of them there projects a round knob, and this alone +is pressed into the mould and makes the hollow part of the cupel. The +part which is next to the knob corresponds to the upper part of the +mould. + +So much for these matters. I will now speak of the preparation of the +ore for assaying. It is prepared by roasting, burning, crushing, and +washing. It is necessary to take a fixed weight of ore in order that one +may determine how great a portion of it these preparations consume. The +hard stone containing the metal is burned in order that, when its +hardness has been overcome, it can be crushed and washed; indeed, the +very hardest kind, before it is burned, is sprinkled with vinegar, in +order that it may more rapidly soften in the fire. The soft stone should +be broken with a hammer, crushed in a mortar and reduced to powder; then +it should be washed and then dried again. If earth is mixed with the +mineral, it is washed in a basin, and that which settles is assayed in +the fire after it is dried. All mining products which are washed must +again be dried. But ore which is rich in metal is neither burned nor +crushed nor washed, but is roasted, lest that method of preparation +should lose some of the metal. When the fires have been kindled, this +kind of ore is roasted in an enclosed pot, which is stopped up with +lute. A less valuable ore is even burned on a hearth, being placed upon +the charcoal; for we do not make a great expenditure upon metals, if +they are not worth it. However, I will go into fuller details as to all +these methods of preparing ore, both a little later, and in the +following Book. + +For the present, I have decided to explain those things which mining +people usually call fluxes[6] because they are added to ores, not only +for assaying, but also for smelting. Great power is discovered in all +these fluxes, but we do not see the same effects produced in every case; +and some are of a very complicated nature. For when they have been mixed +with the ore and are melted in either the assay or the smelting furnace, +some of them, because they melt easily, to some extent melt the ore; +others, because they either make the ore very hot or penetrate into it, +greatly assist the fire in separating the impurities from the metals, +and they also mix the fused part with the lead, or they partly protect +from the fire the ore whose metal contents would be either consumed in +the fire, or carried up with the fumes and fly out of the furnace; some +fluxes absorb the metals. To the first order belongs lead, whether it be +reduced to little granules or resolved into ash by fire, or red-lead[7], +or ochre made from lead[8], or litharge, or hearth-lead, or galena; +also copper, the same either roasted or in leaves or filings[9]; also +the slags of gold, silver, copper, and lead; also soda[10], its slags, +saltpetre, burned alum, vitriol, _sal tostus_, and melted salt[11]; +stones which easily melt in hot furnaces, the sand which is made from +them[12]; soft _tophus_[13], and a certain white schist[14]. But lead, +its ashes, red-lead, ochre, and litharge, are more efficacious for ores +which melt easily; hearth-lead for those which melt with difficulty; and +galena for those which melt with greater difficulty. To the second order +belong iron filings, their slag, _sal artificiosus_, argol, dried lees +of vinegar[15], and the lees of the _aqua_ which separates gold from +silver[16]; these lees and _sal artificiosus_ have the power of +penetrating into ore, the argol to a considerable degree, the lees of +vinegar to a greater degree, but most of all those of the _aqua_ which +separates gold from silver; filings and slags of iron, since they melt +more slowly, have the power of heating the ore. To the third order +belong pyrites, the cakes which are melted from them, soda, its slags, +salt, iron, iron scales, iron filings, iron slags, vitriol, the sand +which is resolved from stones which easily melt in the fire, and +_tophus_; but first of all are pyrites and the cakes which are melted +from it, for they absorb the metals of the ore and guard them from the +fire which consumes them. To the fourth order belong lead and copper, +and their relations. And so with regard to fluxes, it is manifest that +some are natural, others fall in the category of slags, and the rest are +purged from slag. When we assay ores, we can without great expense add +to them a small portion of any sort of flux, but when we smelt them we +cannot add a large portion without great expense. We must, therefore, +consider how great the cost is, to avoid incurring a greater expense on +smelting an ore than the profit we make out of the metals which it +yields. + +The colour of the fumes which the ore emits after being placed on a hot +shovel or an iron plate, indicates what flux is needed in addition to +the lead, for the purpose of either assaying or smelting. If the fumes +have a purple tint, it is best of all, and the ore does not generally +require any flux whatever. If the fumes are blue, there should be added +cakes melted out of pyrites or other cupriferous rock; if yellow, +litharge and sulphur should be added; if red, glass-galls[17] and salt; +if green, then cakes melted from cupriferous stones, litharge, and +glass-galls; if the fumes are black, melted salt or iron slag, litharge +and white lime rock. If they are white, sulphur and iron which is eaten +with rust; if they are white with green patches, iron slag and sand +obtained from stones which easily melt; if the middle part of the fumes +are yellow and thick, but the outer parts green, the same sand and iron +slag. The colour of the fumes not only gives us information as to the +proper remedies which should be applied to each ore, but also more or +less indication as to the solidified juices which are mixed with it, and +which give forth such fumes. Generally, blue fumes signify that the ore +contains azure yellow, orpiment; red, realgar; green, chrysocolla; +black, black bitumen; white, tin[18]; white with green patches, the same +mixed with chrysocolla; the middle part yellow and other parts green +show that it contains sulphur. Earth, however, and other things dug up +which contain metals, sometimes emit similarly coloured fumes. + +If the ore contains any _stibium_, then iron slag is added to it; if +pyrites, then are added cakes melted from a cupriferous stone and sand +made from stones which easily melt. If the ore contains iron, then +pyrites and sulphur are added; for just as iron slag is the flux for an +ore mixed with sulphur, so on the contrary, to a gold or silver ore +containing iron, from which they are not easily separated, is added +sulphur and sand made from stones which easily melt. + +_Sal artificiosus_[19] suitable for use in assaying ore is made in many +ways. By the first method, equal portions of argol, lees of vinegar, and +urine, are all boiled down together till turned into salt. The second +method is from equal portions of the ashes which wool-dyers use, of +lime, of argol purified, and of melted salt; one _libra_ of each of +these ingredients is thrown into twenty _librae_ of urine; then all are +boiled down to one-third and strained, and afterward there is added to +what remains one _libra_ and four _unciae_ of unmelted salt, eight +pounds of lye being at the same time poured into the pots, with litharge +smeared around on the inside, and the whole is boiled till the salt +becomes thoroughly dry. The third method follows. Unmelted salt, and +iron which is eaten with rust, are put into a vessel, and after urine +has been poured in, it is covered with a lid and put in a warm place for +thirty days; then the iron is washed in the urine and taken out, and the +residue is boiled until it is turned into salt. In the fourth method by +which _sal artificiosus_ is prepared, the lye made from equal portions +of lime and the ashes which wool-dyers use, together with equal portions +of salt, soap, white argol, and saltpetre, are boiled until in the end +the mixture evaporates and becomes salt. This salt is mixed with the +concentrates from washing, to melt them. + +Saltpetre is prepared in the following manner, in order that it may be +suitable for use in assaying ore. It is placed in a pot which is smeared +on the inside with litharge, and lye made of quicklime is repeatedly +poured over it, and it is heated until the fire consumes it. Wherefore +the saltpetre does not kindle with the fire, since it has absorbed the +lime which preserves it, and thus it is prepared[20]. + +The following compositions[21] are recommended to smelt all ores which +the heat of fire breaks up or melts only with difficulty. Of these, one +is made from stones of the third order, which easily melt when thrown +into hot furnaces. They are crushed into pure white powder, and with +half an _uncia_ of this powder there are mixed two _unciae_ of yellow +litharge, likewise crushed. This mixture is put into a scorifier large +enough to hold it, and placed under the muffle of a hot furnace; when +the charge flows like water, which occurs after half an hour, it is +taken out of the furnace and poured on to a stone, and when it has +hardened it has the appearance of glass, and this is likewise crushed. +This powder is sprinkled over any metalliferous ore which does not +easily melt when we are assaying it, and it causes the slag to exude. + +Others, in place of litharge, substitute lead ash,[22] which is made in +the following way: sulphur is thrown into lead which has been melted in +a crucible, and it soon becomes covered with a sort of scum; when this +is removed, sulphur is again thrown in, and the skin which forms is +again taken off; this is frequently repeated, in fact until all the lead +is turned into powder. There is a powerful flux compound which is made +from one _uncia_ each of prepared saltpetre, melted salt, glass-gall, +and argol, and one-third of an _uncia_ of litharge and a _bes_ of glass +ground to powder; this flux, being added to an equal weight of ore, +liquefies it. A more powerful flux is made by placing together in a pot, +smeared on the inside with litharge, equal portions of white argol, +common salt, and prepared saltpetre, and these are heated until a white +powder is obtained from them, and this is mixed with as much litharge; +one part of this compound is mixed with two parts of the ore which is to +be assayed. A still more powerful flux than this is made out of ashes of +black lead, saltpetre, orpiment, _stibium_, and dried lees of the _aqua_ +with which gold workers separate gold from silver. The ashes of lead[23] +are made from one pound of lead and one pound of sulphur; the lead is +flattened out into sheets by pounding with a hammer, and placed +alternately with sulphur in a crucible or pot, and they are heated +together until the fire consumes the sulphur and the lead turns to +ashes. One _libra_ of crushed saltpetre is mixed with one _libra_ of +orpiment similarly ground to powder, and the two are cooked in an iron +pan until they liquefy; they are then poured out, and after cooling are +again ground to powder. A _libra_ of _stibium_ and a _bes_ of the dried +lees (_of what?_) are placed alternately in a crucible and heated to the +point at which they form a button, which is similarly reduced to powder. +A _bes_ of this powder and one _libra_ of the ashes of lead, as well as +a _libra_ of powder made out of the saltpetre and orpiment, are mixed +together and a powder is made from them, one part of which added to two +parts of ore liquefies it and cleanses it of dross. But the most +powerful flux is one which has two _drachmae_ of sulphur and as much +glass-galls, and half an _uncia_ of each of the following,--_stibium_, +salt obtained from boiled urine, melted common salt, prepared saltpetre, +litharge, vitriol, argol, salt obtained from ashes of musk ivy, dried +lees of the _aqua_ by which gold-workers separate gold from silver, alum +reduced by fire to powder, and one _uncia_ of camphor[24] combined with +sulphur and ground into powder. A half or whole portion of this mixture, +as the necessity of the case requires, is mixed with one portion of the +ore and two portions of lead, and put in a scorifier; it is sprinkled +with powder of crushed Venetian glass, and when the mixture has been +heated for an hour and a half or two hours, a button will settle in the +bottom of the scorifier, and from it the lead is soon separated. + +There is also a flux which separates sulphur, orpiment and realgar from +metalliferous ore. This flux is composed of equal portions of iron slag, +white _tophus_, and salt. After these juices have been secreted, the +ores themselves are melted, with argol added to them. There is one flux +which preserves _stibium_ from the fire, that the fire may not consume +it, and which preserves the metals from the _stibium_; and this is +composed of equal portions of sulphur, prepared saltpetre, melted salt, +and vitriol, heated together in lye until no odour emanates from the +sulphur, which occurs after a space of three or four hours.[25] + +It is also worth while to substitute certain other mixtures. Take two +portions of ore properly prepared, one portion of iron filings, and +likewise one portion of salt, and mix; then put them into a scorifier +and place them in a muffle furnace; when they are reduced by the fire +and run together, a button will settle in the bottom of the scorifier. +Or else take equal portions of ore and of lead ochre, and mix with them +a small quantity of iron filings, and put them into a scorifier, then +scatter iron filings over the mixture. Or else take ore which has been +ground to powder and sprinkle it in a crucible, and then sprinkle over +it an equal quantity of salt that has been three or four times moistened +with urine and dried; then, again and again alternately, powdered ore +and salt; next, after the crucible has been covered with a lid and +sealed, it is placed upon burning charcoal. Or else take one portion of +ore, one portion of minute lead granules, half a portion of Venetian +glass, and the same quantity of glass-galls. Or else take one portion of +ore, one portion of lead granules, half a portion of salt, one-fourth of +a portion of argol, and the same quantity of lees of the _aqua_ which +separates gold from silver. Or else take equal portions of prepared ore +and a powder in which there are equal portions of very minute lead +granules, melted salt, _stibium_ and iron slag. Or else take equal +portions of gold ore, vitriol, argol, and of salt. So much for the +fluxes. + +In the assay furnace, when it has been prepared in the way in which I +have described, is first placed a muffle. Then selected pieces of live +charcoals are laid on it, for, from pieces of inferior quality, a great +quantity of ash collects around the muffle and hinders the action of the +fire. Then the scorifiers are placed under the muffle with tongs, and +glowing coals are placed under the fore part of the muffle to warm the +scorifiers more quickly; and when the lead or ore is to be placed in the +scorifiers, they are taken out again with the tongs. When the scorifiers +glow in the heat, first of all the ash or small charcoals, if any have +fallen into them, should be blown away with an iron pipe two feet long +and a digit in diameter; this same thing must be done if ash or small +coal has fallen into the cupels. Next, put in a small ball of lead with +the tongs, and when this lead has begun to be turned into fumes and +consumed, add to it the prepared ore wrapped in paper. It is preferable +that the assayer should wrap it in paper, and in this way put it in the +scorifier, than that he should drop it in with a copper ladle; for when +the scorifiers are small, if he uses a ladle he frequently spills some +part of the ore. When the paper is burnt, he stirs the ore with a small +charcoal held in the tongs, so that the lead may absorb the metal which +is mixed in the ore; when this mixture has taken place, the slag partly +adheres by its circumference to the scorifier and makes a kind of black +ring, and partly floats on the lead in which is mixed the gold or +silver; then the slag must be removed from it. + +The lead used must be entirely free from every trace of silver, as is +that which is known as _Villacense_.[26] But if this kind is not +obtainable, the lead must be assayed separately, to determine with +certainty that proportion of silver it contains, so that it may be +deducted from the calculation of the ore, and the result be exact; for +unless such lead be used, the assay will be false and misleading. The +lead balls are made with a pair of iron tongs, about one foot long; its +iron claws are so formed that when pressed together they are egg-shaped; +each claw contains a hollow cup, and when the claws are closed there +extends upward from the cup a passage, so there are two openings, one of +which leads to each hollow cup. And so when the molten lead is poured in +through the openings, it flows down into the hollow cup, and two balls +are formed by one pouring. + +In this place I ought not to omit mention of another method of assaying +employed by some assayers. They first of all place prepared ore in the +scorifiers and heat it, and afterward they add the lead. Of this method +I cannot approve, for in this way the ore frequently becomes cemented, +and for this reason it does not stir easily afterward, and is very slow +in mixing with the lead. + +[Illustration 240a (Tongs): A--Claws of the tongs. B--Iron, giving form +of an egg. C--Opening.] + +If the whole space of the furnace covered by the muffle is not filled +with scorifiers, cupels are put in the empty space, in order that they +may become warmed in the meantime. Sometimes, however, it is filled with +scorifiers, when we are assaying many different ores, or many portions +of one ore at the same time. Although the cupels are usually dried in +one hour, yet smaller ones are done more quickly, and the larger ones +more slowly. Unless the cupels are heated before the metal mixed with +lead is placed in them, they frequently break, and the lead always +sputters and sometimes leaps out of them; if the cupel is broken or the +lead leaps out of it, it is necessary to assay another portion of ore; +but if the lead only sputters, then the cupels should be covered with +broad thin pieces of glowing charcoal, and when the lead strikes these, +it falls back again, and thus the mixture is slowly exhaled. Further, if +in the cupellation the lead which is in the mixture is not consumed, but +remains fixed and set, and is covered by a kind of skin, this is a sign +that it has not been heated by a sufficiently hot fire; put into the +mixture, therefore, a dry pine stick, or a twig of a similar tree, and +hold it in the hand in order that it can be drawn away when it has been +heated. Then take care that the heat is sufficient and equal; if the +heat has not passed all round the charge, as it should when everything +is done rightly, but causes it to have a lengthened shape, so that it +appears to have a tail, this is a sign that the heat is deficient where +the tail lies. Then in order that the cupel may be equally heated by the +fire, turn it around with a small iron hook, whose handle is likewise +made of iron and is a foot and a half long. + +[Illustration 240b (Hook): Small iron hook.] + +Next, if the mixture has not enough lead, add as much of it as is +required with the iron tongs, or with the brass ladle to which is +fastened a very long handle. In order that the charge may not be cooled, +warm the lead beforehand. But it is better at first to add as much lead +as is required to the ore which needs melting, rather than afterward +when the melting has been half finished, that the whole quantity may not +vanish in fumes, but part of it remain fast. When the heat of the fire +has nearly consumed the lead, then is the time when the gold and silver +gleam in their varied colours, and when all the lead has been consumed +the gold or silver settles in the cupel. Then as soon as possible remove +the cupel out of the furnace, and take the button out of it while it is +still warm, in order that it does not adhere to the ashes. This +generally happens if the button is already cold when it is taken out. If +the ashes do adhere to it, do not scrape it with a knife, lest some of +it be lost and the assay be erroneous, but squeeze it with the iron +tongs, so that the ashes drop off through the pressure. Finally, it is +of advantage to make two or three assays of the same ore at the same +time, in order that if by chance one is not successful, the second, or +in any event the third, may be certain. + +[Illustration 241 (Shield for Muffle Furnace): A--Handle of tablet. +B--Its crack.] + +While the assayer is assaying the ore, in order to prevent the great +heat of the fire from injuring his eyes, it will be useful for him +always to have ready a thin wooden tablet, two palms wide, with a handle +by which it may be held, and with a slit down the middle in order that +he may look through it as through a crack, since it is necessary for him +to look frequently within and carefully to consider everything. + +Now the lead which has absorbed the silver from a metallic ore is +consumed in the cupel by the heat in the space of three quarters of an +hour. When the assays are completed the muffle is taken out of the +furnace, and the ashes removed with an iron shovel, not only from the +brick and iron furnaces, but also from the earthen one, so that the +furnace need not be removed from its foundation. + +From ore placed in the triangular crucible a button is melted out, from +which metal is afterward made. First of all, glowing charcoal is put +into the iron hoop, then is put in the triangular crucible, which +contains the ore together with those things which can liquefy it and +purge it of its dross; then the fire is blown with the double bellows, +and the ore is heated until the button settles in the bottom of the +crucible. We have explained that there are two methods of assaying +ore,--one, by which the lead is mixed with ore in the scorifier and +afterward again separated from it in the cupel; the other, by which it +is first melted in the triangular earthen crucible and afterward mixed +with lead in the scorifier, and later separated from it in the cupel. +Now let us consider which is more suitable for each ore, or, if neither +is suitable, by what other method in one way or another we can assay it. + +We justly begin with a gold ore, which we assay by both methods, for if +it is rich and seems not to be strongly resistant to fire, but to +liquefy easily, one _centumpondium_ of it (known to us as the lesser +weights),[27] together with one and a half, or two _unciae_ of lead of +the larger weights, are mixed together and placed in the scorifier, and +the two are heated in the fire until they are well mixed. But since such +an ore sometimes resists melting, add a little salt to it, either _sal +torrefactus_ or _sal artificiosus_, for this will subdue it, and prevent +the alloy from collecting much dross; stir it frequently with an iron +rod, in order that the lead may flow around the gold on every side, and +absorb it and cast out the waste. When this has been done, take out the +alloy and cleanse it of slag; then place it in the cupel and heat it +until it exhales all the lead, and a bead of gold settles in the bottom. + +If the gold ore is seen not to be easily melted in the fire, roast it +and extinguish it with brine. Do this again and again, for the more +often you roast it and extinguish it, the more easily the ore can be +crushed fine, and the more quickly does it melt in the fire and give up +whatever dross it possesses. Mix one part of this ore, when it has been +roasted, crushed, and washed, with three parts of some powder compound +which melts ore, and six parts of lead. Put the charge into the +triangular crucible, place it in the iron hoop to which the double +bellows reaches, and heat first in a slow fire, and afterward gradually +in a fiercer fire, till it melts and flows like water. If the ore does +not melt, add to it a little more of these fluxes, mixed with an equal +portion of yellow litharge, and stir it with a hot iron rod until it all +melts. Then take the crucible out of the hoop, shake off the button when +it has cooled, and when it has been cleansed, melt first in the +scorifier and afterward in the cupel. Finally, rub the gold which has +settled in the bottom of the cupel, after it has been taken out and +cooled, on the touchstone, in order to find out what proportion of +silver it contains. Another method is to put a _centumpondium_ (of the +lesser weights) of gold ore into the triangular crucible, and add to it +a _drachma_ (of the larger weights) of glass-galls. If it resists +melting, add half a _drachma_ of roasted argol, and if even then it +resists, add the same quantity of roasted lees of vinegar, or lees of +the _aqua_ which separates gold from silver, and the button will settle +in the bottom of the crucible. Melt this button again in the scorifier +and a third time in the cupel. + +We determine in the following way, before it is melted in the muffle +furnace, whether pyrites contains gold in it or not: if, after being +three times roasted and three times quenched in sharp vinegar, it has +not broken nor changed its colour, there is gold in it. The vinegar by +which it is quenched should be mixed with salt that is put in it, and +frequently stirred and dissolved for three days. Nor is pyrites devoid +of gold, when, after being roasted and then rubbed on the touchstone, it +colours the touchstone in the same way that it coloured it when rubbed +in its crude state. Nor is gold lacking in that, whose concentrates from +washing, when heated in the fire, easily melt, giving forth little smell +and remaining bright; such concentrates are heated in the fire in a +hollowed piece of charcoal covered over with another charcoal. + +We also assay gold ore without fire, but more often its sand or the +concentrates which have been made by washing, or the dust gathered up by +some other means. A little of it is slightly moistened with water and +heated until it begins to exhale an odour, and then to one portion of +ore are placed two portions of quicksilver[28] in a wooden dish as deep +as a basin. They are mixed together with a little brine, and are then +ground with a wooden pestle for the space of two hours, until the +mixture becomes of the thickness of dough, and the quicksilver can no +longer be distinguished from the concentrates made by the washing, nor +the concentrates from the quicksilver. Warm, or at least tepid, water is +poured into the dish and the material is washed until the water runs out +clear. Afterward cold water is poured into the same dish, and soon the +quicksilver, which has absorbed all the gold, runs together into a +separate place away from the rest of the concentrates made by washing. +The quicksilver is afterward separated from the gold by means of a pot +covered with soft leather, or with canvas made of woven threads of +cotton; the amalgam is poured into the middle of the cloth or leather, +which sags about one hand's breadth; next, the leather is folded over +and tied with a waxed string, and the dish catches the quicksilver which +is squeezed through it. As for the gold which remains in the leather, it +is placed in a scorifier and purified by being placed near glowing +coals. Others do not wash away the dirt with warm water, but with strong +lye and vinegar, for they pour these liquids into the pot, and also +throw into it the quicksilver mixed with the concentrates made by +washing. Then they set the pot in a warm place, and after twenty-four +hours pour out the liquids with the dirt, and separate the quicksilver +from the gold in the manner which I have described. Then they pour urine +into a jar set in the ground, and in the jar place a pot with holes in +the bottom, and in the pot they place the gold; then the lid is put on +and cemented, and it is joined with the jar; they afterward heat it till +the pot glows red. After it has cooled, if there is copper in the gold +they melt it with lead in a cupel, that the copper may be separated from +it; but if there is silver in the gold they separate them by means of +the _aqua_ which has the power of parting these two metals. There are +some who, when they separate gold from quicksilver, do not pour the +amalgam into a leather, but put it into a gourd-shaped earthen vessel, +which they place in the furnace and heat gradually over burning +charcoal; next, with an iron plate, they cover the opening of the +operculum, which exudes vapour, and as soon as it has ceased to exude, +they smear it with lute and heat it for a short time; then they remove +the operculum from the pot, and wipe off the quicksilver which adheres +to it with a hare's foot, and preserve it for future use. By the latter +method, a greater quantity of quicksilver is lost, and by the former +method, a smaller quantity. + +If an ore is rich in silver, as is _rudis_ silver[29], frequently silver +glance, or rarely ruby silver, gray silver, black silver, brown silver, +or yellow silver, as soon as it is cleansed and heated, a +_centumpondium_ (of the lesser weights) of it is placed in an _uncia_ of +molten lead in a cupel, and is heated until the lead exhales. But if the +ore is of poor or moderate quality, it must first be dried, then +crushed, and then to a _centumpondium_ (of the lesser weights) an +_uncia_ of lead is added, and it is heated in the scorifier until it +melts. If it is not soon melted by the fire, it should be sprinkled with +a little powder of the first order of fluxes, and if then it does not +melt, more is added little by little until it melts and exudes its slag; +that this result may be reached sooner, the powder which has been +sprinkled over it should be stirred in with an iron rod. When the +scorifier has been taken out of the assay furnace, the alloy should be +poured into a hole in a baked brick; and when it has cooled and been +cleansed of the slag, it should be placed in a cupel and heated until it +exhales all its lead; the weight of silver which remains in the cupel +indicates what proportion of silver is contained in the ore. + +We assay copper ore without lead, for if it is melted with it, the +copper usually exhales and is lost. Therefore, a certain weight of such +an ore is first roasted in a hot fire for about six or eight hours; +next, when it has cooled, it is crushed and washed; then the +concentrates made by washing are again roasted, crushed, washed, dried, +and weighed. The portion which it has lost whilst it is being roasted +and washed is taken into account, and these concentrates by washing +represent the cake which will be melted out of the copper ore. Place +three _centumpondia_ (lesser weights) of this, mixed with three +_centumpondia_ (lesser weights) each of copper scales[30], saltpetre, +and Venetian glass, mixed, into the triangular crucible, and place it in +the iron hoop which is set on the hearth in front of the double bellows. +Cover the crucible with charcoal in such a way that nothing may fall +into the ore which is to be melted, and so that it may melt more +quickly. At first blow a gentle blast with the bellows in order that the +ore may be heated gradually in the fire; then blow strongly till it +melts, and the fire consumes that which has been added to it, and the +ore itself exudes whatever slag it possesses. Next, cool the crucible +which has been taken out, and when this is broken you will find the +copper; weigh this, in order to ascertain how great a portion of the ore +the fire has consumed. Some ore is only once roasted, crushed, and +washed; and of this kind of concentrates, three _centumpondia_ (lesser +weights) are taken with one _centumpondium_ each of common salt, argol +and glass-galls. Heat them in the triangular crucible, and when the +mixture has cooled a button of pure copper will be found, if the ore is +rich in this metal. If, however, it is less rich, a stony lump results, +with which the copper is intermixed; this lump is again roasted, +crushed, and, after adding stones which easily melt and saltpetre, it is +again melted in another crucible, and there settles in the bottom of the +crucible a button of pure copper. If you wish to know what proportion of +silver is in this copper button, melt it in a cupel after adding lead. +With regard to this test I will speak later. + +Those who wish to know quickly what portion of silver the copper ore +contains, roast the ore, crush and wash it, then mix a little yellow +litharge with one _centumpondium_ (lesser weights) of the concentrates, +and put the mixture into a scorifier, which they place under the muffle +in a hot furnace for the space of half an hour. When the slag exudes, by +reason of the melting force which is in the litharge, they take the +scorifier out; when it has cooled, they cleanse it of slag and again +crush it, and with one _centumpondium_ of it they mix one and a half +_unciae_ of lead granules. They then put it into another scorifier, +which they place under the muffle in a hot furnace, adding to the +mixture a little of the powder of some one of the fluxes which cause ore +to melt; when it has melted they take it out, and after it has cooled, +cleanse it of slag; lastly, they heat it in the cupel till it has +exhaled all of the lead, and only silver remains. + +Lead ore may be assayed by this method: crush half an _uncia_ of pure +lead-stone and the same quantity of the _chrysocolla_ which they call +borax, mix them together, place them in a crucible, and put a glowing +coal in the middle of it. As soon as the borax crackles and the +lead-stone melts, which soon occurs, remove the coal from the crucible, +and the lead will settle to the bottom of it; weigh it out, and take +account of that portion of it which the fire has consumed. If you also +wish to know what portion of silver is contained in the lead, melt the +lead in the cupel until all of it exhales. + +Another way is to roast the lead ore, of whatsoever quality it be, wash +it, and put into the crucible one _centumpondium_ of the concentrates, +together with three _centumpondia_ of the powdered compound which melts +ore, mixed together, and place it in the iron hoop that it may melt; +when it has cooled, cleanse it of its slag, and complete the test as I +have already said. Another way is to take two _unciae_ of prepared ore, +five _drachmae_ of roasted copper, one _uncia_ of glass, or glass-galls +reduced to powder, a _semi-uncia_ of salt, and mix them. Put the mixture +into the triangular crucible, and heat it over a gentle fire to prevent +it from breaking; when the mixture has melted, blow the fire vigorously +with the bellows; then take the crucible off the live coals and let it +cool in the open air; do not pour water on it, lest the lead button +being acted upon by the excessive cold should become mixed with the +slag, and the assay in this way be erroneous. When the crucible has +cooled, you will find in the bottom of it the lead button. Another way +is to take two _unciae_ of ore, a _semi-uncia_ of litharge, two +_drachmae_ of Venetian glass and a _semi-uncia_ of saltpetre. If there +is difficulty in melting the ore, add to it iron filings, which, since +they increase the heat, easily separate the waste from lead and other +metals. By the last way, lead ore properly prepared is placed in the +crucible, and there is added to it only the sand made from stones which +easily melt, or iron filings, and then the assay is completed as +formerly. + +You can assay tin ore by the following method. First roast it, then +crush, and afterward wash it; the concentrates are again roasted, +crushed, and washed. Mix one and a half _centumpondia_ of this with one +_centumpondium_ of the _chrysocolla_ which they call borax; from the +mixture, when it has been moistened with water, make a lump. Afterwards, +perforate a large round piece of charcoal, making this opening a palm +deep, three digits wide on the upper side and narrower on the lower +side; when the charcoal is put in its place the latter should be on the +bottom and the former uppermost. Let it be placed in a crucible, and let +glowing coal be put round it on all sides; when the perforated piece of +coal begins to burn, the lump is placed in the upper part of the +opening, and it is covered with a wide piece of glowing coal, and after +many pieces of coal have been put round it, a hot fire is blown up with +the bellows, until all the tin has run out of the lower opening of the +charcoal into the crucible. Another way is to take a large piece of +charcoal, hollow it out, and smear it with lute, that the ore may not +leap out when white hot. Next, make a small hole through the middle of +it, then fill up the large opening with small charcoal, and put the ore +upon this; put fire in the small hole and blow the fire with the nozzle +of a hand bellows; place the piece of charcoal in a small crucible, +smeared with lute, in which, when the melting is finished, you will find +a button of tin. + +In assaying bismuth ore, place pieces of ore in the scorifier, and put +it under the muffle in a hot furnace; as soon as they are heated, they +drip with bismuth, which runs together into a button. + +Quicksilver ore is usually tested by mixing one part of broken ore with +three-parts of charcoal dust and a handful of salt. Put the mixture into +a crucible or a pot or a jar, cover it with a lid, seal it with lute, +place it on glowing charcoal, and as soon as a burnt cinnabar colour +shows in it, take out the vessel; for if you continue the heat too long +the mixture exhales the quicksilver with the fumes. The quicksilver +itself, when it has become cool, is found in the bottom of the crucible +or other vessel. Another way is to place broken ore in a gourd-shaped +earthen vessel, put it in the assay furnace, and cover with an operculum +which has a long spout; under the spout, put an ampulla to receive the +quicksilver which distills. Cold water should be poured into the +ampulla, so that the quicksilver which has been heated by the fire may +be continuously cooled and gathered together, for the quicksilver is +borne over by the force of the fire, and flows down through the spout of +the operculum into the ampulla. We also assay quicksilver ore in the +very same way in which we smelt it. This I will explain in its proper +place. + +Lastly, we assay iron ore in the forge of a blacksmith. Such ore is +burned, crushed, washed, and dried; a magnet is laid over the +concentrates, and the particles of iron are attracted to it; these are +wiped off with a brush, and are caught in a crucible, the magnet being +continually passed over the concentrates and the particles wiped off, so +long as there remain any particles which the magnet can attract to it. +These particles are heated in the crucible with saltpetre until they +melt, and an iron button is melted out of them. If the magnet easily and +quickly attracts the particles to it, we infer that the ore is rich in +iron; if slowly, that it is poor; if it appears actually to repel the +ore, then it contains little or no iron. This is enough for the assaying +of ores. + +I will now speak of the assaying of the metal alloys. This is done both +by coiners and merchants who buy and sell metal, and by miners, but most +of all by the owners and mine masters, and by the owners and masters of +the works in which the metals are smelted, or in which one metal is +parted from another. + +First I will describe the way assays are usually made to ascertain what +portion of precious metal is contained in base metal. Gold and silver +are now reckoned as precious metals and all the others as base metals. +Once upon a time the base metals were burned up, in order that the +precious metals should be left pure; the Ancients even discovered by +such burning what portion of gold was contained in silver, and in this +way all the silver was consumed, which was no small loss. However, the +famous mathematician, Archimedes[31], to gratify King Hiero, invented a +method of testing the silver, which was not very rapid, and was more +accurate for testing a large mass than a small one. This I will explain +in my commentaries. The alchemists have shown us a way of separating +silver from gold by which neither of them is lost[32]. + +Gold which contains silver,[33] or silver which contains gold, is first +rubbed on the touchstone. Then a needle in which there is a similar +amount of gold or silver is rubbed on the same touchstone, and from the +lines which are produced in this way, is perceived what portion of +silver there is in the gold, or what portion of gold there is in the +silver. Next there is added to the silver which is in the gold, enough +silver to make it three times as much as the gold. Then lead is placed +in a cupel and melted; a little later, a small amount of copper is put +in it, in fact, half an _uncia_ of it, or half an _uncia_ and a +_sicilicus_ (of the smaller weights) if the gold or silver does not +contain any copper. The cupel, when the lead and copper are wanting, +attracts the particles of gold and silver, and absorbs them. Finally, +one-third of a _libra_ of the gold, and one _libra_[34] of the silver +must be placed together in the same cupel and melted; for if the gold +and silver were first placed in the cupel and melted, as I have already +said, it absorbs particles of them, and the gold, when separated from +the silver, will not be found pure. These metals are heated until the +lead and the copper are consumed, and again, the same weight of each is +melted in the same manner in another cupel. The buttons are pounded with +a hammer and flattened out, and each little leaf is shaped in the form +of a tube, and each is put into a small glass ampulla. Over these there +is poured one _uncia_ and one _drachma_ (of the large weight) of the +third quality _aqua valens_, which I will describe in the Tenth Book. +This is heated over a slow fire, and small bubbles, resembling pearls in +shape, will be seen to adhere to the tubes. The redder the _aqua_ +appears, the better it is judged to be; when the redness has vanished, +small white bubbles are seen to be resting on the tubes, resembling +pearls not only in shape, but also in colour. After a short time the +_aqua_ is poured off and other is poured on; when this has again raised +six or eight small white bubbles, it is poured off and the tubes are +taken out and washed four or five times with spring water; or if they +are heated with the same water, when it is boiling, they will shine more +brilliantly. Then they are placed in a saucer, which is held in the hand +and gradually dried by the gentle heat of the fire; afterward the saucer +is placed over glowing charcoal and covered with a charcoal, and a +moderate blast is blown upon it with the mouth and then a blue flame +will be emitted. In the end the tubes are weighed, and if their weights +prove equal, he who has undertaken this work has not laboured in vain. +Lastly, both are placed in another balance-pan and weighed; of each tube +four grains must not be counted, on account of the silver which remains +in the gold and cannot be separated from it. From the weight of the +tubes we learn the weight both of the gold and of the silver which is in +the button. If some assayer has omitted to add so much silver to the +gold as to make it three times the quantity, but only double, or two and +a half times as much, he will require the stronger quality of _aqua_ +which separates gold from silver, such as the fourth quality. Whether +the _aqua_ which he employs for gold and silver is suitable for the +purpose, or whether it is more or less strong than is right, is +recognised by its effect. That of medium strength raises the little +bubbles on the tubes and is found to colour the ampulla and the +operculum a strong red; the weaker one is found to colour them a light +red, and the stronger one to break the tubes. To pure silver in which +there is some portion of gold, nothing should be added when they are +being heated in the cupel prior to their being parted, except a _bes_ of +lead and one-fourth or one-third its amount of copper of the lesser +weights. If the silver contains in itself a certain amount of copper, +let it be weighed, both after it has been melted with the lead, and +after the gold has been parted from it; by the former we learn how much +copper is in it, by the latter how much gold. Base metals are burnt up +even to-day for the purpose of assay, because to lose so little of the +metal is small loss, but from a large mass of base metal, the precious +metal is always extracted, as I will explain in Books X. and XI. + +We assay an alloy of copper and silver in the following way. From a few +cakes of copper the assayer cuts out portions, small samples from small +cakes, medium samples from medium cakes, and large samples from large +cakes; the small ones are equal in size to half a hazel nut, the large +ones do not exceed the size of half a chestnut, and those of medium size +come between the two. He cuts out the samples from the middle of the +bottom of each cake. He places the samples in a new, clean, triangular +crucible and fixes to them pieces of paper upon which are written the +weight of the cakes of copper, of whatever size they may be; for +example, he writes, "These samples have been cut from copper which +weighs twenty _centumpondia_." When he wishes to know how much silver +one _centumpondium_ of copper of this kind has in it, first of all he +throws glowing coals into the iron hoop, then adds charcoal to it. When +the fire has become hot, the paper is taken out of the crucible and put +aside, he then sets that crucible on the fire and gradually heats it for +a quarter of an hour until it becomes red hot. Then he stimulates the +fire by blowing with a blast from the double bellows for half an hour, +because copper which is devoid of lead requires this time to become hot +and to melt; copper not devoid of lead melts quicker. When he has blown +the bellows for about the space of time stated, he removes the glowing +charcoal with the tongs, and stirs the copper with a splinter of wood, +which he grasps with the tongs. If it does not stir easily, it is a sign +that the copper is not wholly liquefied; if he finds this is the case, +he again places a large piece of charcoal in the crucible, and replaces +the glowing charcoal which had been removed, and again blows the bellows +for a short time. When all the copper has melted he stops using the +bellows, for if he were to continue to use them, the fire would consume +part of the copper, and then that which remained would be richer than +the cake from which it had been cut; this is no small mistake. +Therefore, as soon as the copper has become sufficiently liquefied, he +pours it out into a little iron mould, which may be large or small, +according as more or less copper is melted in the crucible for the +purpose of the assay. The mould has a handle, likewise made of iron, by +which it is held when the copper is poured in, after which, he plunges +it into a tub of water placed near at hand, that the copper may be +cooled. Then he again dries the copper by the fire, and cuts off its +point with an iron wedge; the portion nearest the point he hammers on an +anvil and makes into a leaf, which he cuts into pieces. + +[Illustration 250 (Copper Mould for Assaying): A--Iron mould. B--Its +handle.] + +Others stir the molten copper with a stick of linden tree charcoal, and +then pour it over a bundle of new clean birch twigs, beneath which is +placed a wooden tub of sufficient size and full of water, and in this +manner the copper is broken up into little granules as small as hemp +seeds. Others employ straw in place of twigs. Others place a broad stone +in a tub and pour in enough water to cover the stone, then they run out +the molten copper from the crucible on to the stone, from which the +minute granules roll off; others pour the molten copper into water and +stir it until it is resolved into granules. The fire does not easily +melt the copper in the cupel unless it has been poured and a thin leaf +made of it, or unless it has been resolved into granules or made into +filings; and if it does not melt, all the labour has been undertaken in +vain. In order that they may be accurately weighed out, silver and lead +are resolved into granules in the same manner as copper. But to return +to the assay of copper. When the copper has been prepared by these +methods, if it is free of lead and iron, and rich in silver, to each +_centumpondium_ (lesser weights) add one and a half _unciae_ of lead +(larger weights). If, however, the copper contains some lead, add one +_uncia_ of lead; if it contains iron, add two _unciae_. First put the +lead into a cupel, and after it begins to smoke, add the copper; the +fire generally consumes the copper, together with the lead, in about one +hour and a quarter. When this is done, the silver will be found in the +bottom of the cupel. The fire consumes both of those metals more quickly +if they are heated in that furnace which draws in air. It is better to +cover the upper half of it with a lid, and not only to put on the muffle +door, but also to close the window of the muffle door with a piece of +charcoal, or with a piece of brick. If the copper be such that the +silver can only be separated from it with difficulty, then before it is +tested with fire in the cupel, lead should first be put into the +scorifier, and then the copper should be added with a moderate quantity +of melted salt, both that the lead may absorb the copper and that the +copper may be cleansed of the dross which abounds in it. + +Tin which contains silver should not at the beginning of the assay be +placed in a cupel, lest the silver, as often happens, be consumed and +converted into fumes, together with the tin. As soon as the lead[35] has +begun to fume in the scorifier, then add that[36] to it. In this way the +lead will take the silver and the tin will boil and turn into ashes, +which may be removed with a wooden splinter. The same thing occurs if +any alloy is melted in which there is tin. When the lead has absorbed +the silver which was in the tin, then, and not till then, it is heated +in the cupel. First place the lead with which the silver is mixed, in an +iron pan, and stand it on a hot furnace and let it melt; afterward pour +this lead into a small iron mould, and then beat it out with a hammer on +an anvil and make it into leaves in the same way as the copper. Lastly, +place it in the cupel, which assay can be carried out in the space of +half an hour. A great heat is harmful to it, for which reason there is +no necessity either to cover the half of the furnace with a lid or to +close up its mouth. + +The minted metal alloys, which are known as money, are assayed in the +following way. The smaller silver coins which have been picked out from +the bottom and top and sides of a heap are first carefully cleansed; +then, after they have been melted in the triangular crucible, they are +either resolved into granules, or made into thin leaves. As for the +large coins which weigh a _drachma_, a _sicilicus_, half an _uncia_, or +an _uncia_, beat them into leaves. Then take a _bes_ of the granules, or +an equal weight of the leaves, and likewise take another _bes_ in the +same way. Wrap each sample separately in paper, and afterwards place two +small pieces of lead in two cupels which have first been heated. The +more precious the money is, the smaller portion of lead do we require +for the assay, the more base, the larger is the portion required; for if +a _bes_ of silver is said to contain only half an _uncia_ or one _uncia_ +of copper, we add to the _bes_ of granules half an _uncia_ of lead. If +it is composed of equal parts of silver and copper, we add an _uncia_ of +lead, but if in a _bes_ of copper there is only half an _uncia_ or one +_uncia_ of silver, we add an _uncia_ and a half of lead. As soon as the +lead has begun to fume, put into each cupel one of the papers in which +is wrapped the sample of silver alloyed with copper, and close the mouth +of the muffle with charcoal. Heat them with a gentle fire until all the +lead and copper are consumed, for a hot fire by its heat forces the +silver, combined with a certain portion of lead, into the cupel, in +which way the assay is rendered erroneous. Then take the beads out of +the cupel and clean them of dross. If neither depresses the pan of the +balance in which it is placed, but their weight is equal, the assay has +been free from error; but if one bead depresses its pan, then there is +an error, for which reason the assay must be repeated. If the _bes_ of +coin contains but seven _unciae_ of pure silver it is because the King, +or Prince, or the State who coins the money, has taken one _uncia_, +which he keeps partly for profit and partly for the expense of coining, +he having added copper to the silver. Of all these matters I have +written extensively in my book _De Precio Metallorum et Monetis_. + +We assay gold coins in various ways. If there is copper mixed with the +gold, we melt them by fire in the same way as silver coins; if there is +silver mixed with the gold, they are separated by the strongest _aqua +valens_; if there is copper and silver mixed with the gold, then in the +first place, after the addition of lead, they are heated in the cupel +until the fire consumes the copper and the lead, and afterward the gold +is parted from the silver. + +It remains to speak of the touchstone[37] with which gold and silver are +tested, and which was also used by the Ancients. For although the assay +made by fire is more certain, still, since we often have no furnace, nor +muffle, nor crucibles, or some delay must be occasioned in using them, +we can always rub gold or silver on the touchstone, which we can have in +readiness. Further, when gold coins are assayed in the fire, of what use +are they afterward? A touchstone must be selected which is thoroughly +black and free of sulphur, for the blacker it is and the more devoid of +sulphur, the better it generally is; I have written elsewhere of its +nature[38]. First the gold is rubbed on the touchstone, whether it +contains silver or whether it is obtained from the mines or from the +smelting; silver also is rubbed in the same way. Then one of the +needles, that we judge by its colour to be of similar composition, is +rubbed on the touchstone; if this proves too pale, another needle which +has a stronger colour is rubbed on the touchstone; and if this proves +too deep in colour, a third which has a little paler colour is used. For +this will show us how great a proportion of silver or copper, or silver +and copper together, is in the gold, or else how great a proportion of +copper is in silver. + +These needles are of four kinds.[39] The first kind are made of gold and +silver, the second of gold and copper, the third of gold, silver, and +copper, and the fourth of silver and copper. The first three kinds of +needles are used principally for testing gold, and the fourth for +silver. Needles of this kind are prepared in the following ways. The +lesser weights correspond proportionately to the larger weights, and +both of them are used, not only by mining people, but by coiners also. +The needles are made in accordance with the lesser weights, and each set +corresponds to a _bes_, which, in our own vocabulary, is called a +_mark_. The _bes_, which is employed by those who coin gold, is divided +into twenty-four double _sextulae_, which are now called after the +Greek name _ceratia_; and each double _sextula_ is divided into four +_semi-sextulae_, which are called _granas_; and each _semi-sextula_ is +divided into three units of four _siliquae_ each, of which each unit is +called a _grenlin_. If we made the needles to be each four _siliquae_, +there would be two hundred and eighty-eight in a _bes_, but if each were +made to be a _semi-sextula_ or a double _scripula_, then there would be +ninety-six in a _bes_. By these two methods too many needles would be +made, and the majority of them, by reason of the small difference in the +proportion of the gold, would indicate nothing, therefore it is +advisable to make them each of a double _sextula_; in this way +twenty-four needles are made, of which the first is made of twenty-three +_duellae_ of silver and one of gold. Fannius is our authority that the +Ancients called the double _sextula_ a _duella_. When a bar of silver is +rubbed on the touchstone and colours it just as this needle does, it +contains one _duella_ of gold. In this manner we determine by the other +needles what proportion of gold there is, or when the gold exceeds the +silver in weight, what proportion of silver. + +[Illustration 255 (Touch-needles)] + +The needles are made[40]:-- + + The 1st needle of 23 _duellae_ of silver and 1 _duella_ of gold. + " 2nd " 22 " " 2 _duellae_ of gold. + " 3rd " 21 " " 3 " " + " 4th " 20 " " 4 " " + " 5th " 19 " " 5 " " + " 6th " 18 " " 6 " " + " 7th " 17 " " 7 " " + " 8th " 16 " " 8 " " + " 9th " 15 " " 9 " " + " 10th " 14 " " 10 " " + " 11th " 13 " " 11 " " + " 12th " 12 " " 12 " " + " 13th " 11 " " 13 " " + " 14th " 10 " " 14 " " + " 15th " 9 " " 15 " " + " 16th " 8 " " 16 " " + " 17th " 7 " " 17 " " + " 18th " 6 " " 18 " " + " 19th " 5 " " 19 " " + " 20th " 4 " " 20 " " + " 21st " 3 " " 21 " " + " 22nd " 2 " " 22 " " + " 23rd " 1 " " 23 " " + " 24th " pure gold + +By the first eleven needles, when they are rubbed on the touchstone, we +test what proportion of gold a bar of silver contains, and with the +remaining thirteen we test what proportion of silver is in a bar of +gold; and also what proportion of either may be in money. + +Since some gold coins are composed of gold and copper, thirteen needles +of another kind are made as follows:-- + + The 1st of 12 _duellae_ of gold and 12 _duellae_ of copper. + " 2nd " 13 " " 11 " " + " 3rd " 14 " " 10 " " + " 4th " 15 " " 9 " " + " 5th " 16 " " 8 " " + " 6th " 17 " " 7 " " + " 7th " 18 " " 6 " " + " 8th " 19 " " 5 " " + " 9th " 20 " " 4 " " + " 10th " 21 " " 3 " " + " 11th " 22 " " 2 " " + " 12th " 23 " " 1 " " + " 13th " pure gold. + +These needles are not much used, because gold coins of that kind are +somewhat rare; the ones chiefly used are those in which there is much +copper. Needles of the third kind, which are composed of gold, silver, +and copper, are more largely used, because such gold coins are common. +But since with the gold there are mixed equal or unequal portions of +silver and copper, two sorts of needles are made. If the proportion of +silver and copper is equal, the needles are as follows:-- + + Gold. Silver. Copper. + The 1st of 12 _duellae_ 6 _duellae_ 0 _sextula_ 6 _duellae_ 0 _sextula_ + " 2nd " 13 " 5 " 1 " 5 " 1 " + " 3rd " 14 " 5 " 5 " + " 4th " 15 " 4 " 1 " 4 " 1 " + " 5th " 16 " 4 " 4 " + " 6th " 17 " 3 " 1 " 3 " 1 " + " 7th " 18 " 3 " 3 " + " 8th " 19 " 2 " 1 " 2 " 1 " + " 9th " 20 " 2 " 2 " + " 10th " 21 " 1 " 1 " 1 " 1 " + " 11th " 22 " 1 " 1 " + " 12th " 23 " 1 " + " 13th " pure gold. + +Some make twenty-five needles, in order to be able to detect the two +_scripula_ of silver or copper which are in a _bes_ of gold. Of these +needles, the first is composed of twelve _duellae_ of gold and six of +silver, and the same number of copper. The second, of twelve _duellae_ +and one _sextula_ of gold and five _duellae_ and one and a half +_sextulae_ of silver, and the same number of _duellae_ and one and a +half _sextulae_ of copper. The remaining needles are made in the same +proportion. + +Pliny is our authority that the Romans could tell to within one +_scripulum_ how much gold was in any given alloy, and how much silver or +copper. + +Needles may be made in either of two ways, namely, in the ways of which +I have spoken, and in the ways of which I am now about to speak. If +unequal portions of silver and copper have been mixed with the gold, +thirty-seven needles are made in the following way:-- + + Gold. Silver. Copper. + _Duellae_. _Duellae_ _Duellae_ + _Sextulae_ _Sextulae_ + _Siliquae_. _Siliquae_. + The 1st of 12 9 0 0 3 0 0 + " 2nd " 12 8 0 0 4 0 0 + " 3rd " 12 7 5 + + " 4th " 13 8 1/2 2 1/2 + " 5th " 13 7 1/2 4 3 1 8 + " 6th " 13 6 1/2 8 4 1 4 + + " 7th " 14 7 1 2 1 + " 8th " 14 6 1 8 3 1/2 4 + " 9th " 14 5 1-1/2 4 4 8 + + " 10th " 15 6 1-1/2 2 1/2 + " 11th " 15 6 3 + " 12th " 15 5 1/2 3 1-1/2 + + " 13th " 16 6 2 + " 14th " 16 5 1/2 4 2 1 8 + " 15th " 16 4 1 8 3 1/2 4 + + " 16th " 17 5 1/2 0 1 1-1/2 + " 17th " 17 4 1 8 2 1/2 4 + " 18th " 17 4 4 2 1-1/2 8 + + " 19th " 18 4 1 1 1 + " 20th " 18 4 0 2 + " 21st " 18 3 1 2 1 + + " 22nd " 19 2 1-1/2 1 1/2 + " 23rd " 19 3 1/2 4 1 1 8 + " 24th " 19 2 1-1/2 8 2 4 + + " 25th " 20 3 1 + " 26th " 20 2 1 8 1 1/2 4 + " 27th " 20 2 1/2 4 1 1 8 + + " 28th " 21 2 1/2 1-1/2 + " 29th " 21 2 1 + " 30th " 21 1 1-1/2 1 1/2 + + " 31st " 22 1 1 1 + " 32nd " 22 1 1/2 4 0 1 8 + " 33rd " 22 1 8 1-1/2 4 + + " 34th " 23 1-1/2 1/2 + " 35th " 23 1 8 1/2 4 + " 36th " 23 1 4 1/2 8 + " 37th " pure gold. + +Since it is rarely found that gold, which has been coined, does not +amount to at least fifteen _duellae_ gold in a _bes_, some make only +twenty-eight needles, and some make them different from those already +described, inasmuch as the alloy of gold with silver and copper is +sometimes differently proportioned. + +These needles are made:-- + + Gold. Silver. Copper. + _Duellae_. _Duellae_ _Duellae_ + _Sextulae_ _Sextulae_ + _Siliquae_. _Siliquae_. + The 1st of 15 6 1 8 2 1/2 4 + " 2nd " 15 6 4 2 1-1/2 8 + " 3rd " 15 5 1/2 3 1-1/2 + + " 4th " 16 6 1/2 1 1-1/2 + " 5th " 16 5 1 8 2 1/2 4 + " 6th " 16 4 1-1/2 8 3 4 + + " 7th " 17 5 1 4 1 1/2 8 + " 8th " 17 5 4 1 1-1/2 8 + " 9th " 17 4 1 4 2 1/2 8 + + " 10th " 18 4 1 1 1 + " 11th " 18 4 2 + " 12th " 18 3 1 2 1 + + " 13th " 19 3 1-1/2 4 1 8 + " 14th " 19 3 1/2 4 1 1 8 + " 15th " 19 2 1-1/2 4 2 8 + + " 16th " 20 3 1 + " 17th " 20 2 1 1 + " 18th " 20 2 2 + + " 19th " 21 2 1/2 4 1 8 + " 20th " 21 1 1-1/2 4 1 8 + " 21st " 21 1 1 8 1 1/2 4 + + " 22nd " 22 1 1 8 1/2 4 + " 23rd " 22 1 1 1 + " 24th " 22 1 1/2 4 1 8 + + " 25th " 23 1-1/2 4 8 + " 26th " 23 1-1/2 1/2 + " 27th " 23 1 8 1/2 4 + " 28th " pure gold + +Next follows the fourth kind of needles, by which we test silver coins +which contain copper, or copper coins which contain silver. The _bes_ by +which we weigh the silver is divided in two different ways. It is either +divided twelve times, into units of five _drachmae_ and one _scripulum_ +each, which the ordinary people call _nummi_[41]; each of these units +we again divide into twenty-four units of four _siliquae_ each, which +the same ordinary people call a _grenlin_; or else the _bes_ is divided +into sixteen _semunciae_ which are called _loths_, each of which is +again divided into eighteen units of four _siliquae_ each, which they +call _grenlin_. Or else the _bes_ is divided into sixteen _semunciae_, +of which each is divided into four _drachmae_, and each _drachma_ into +four _pfennige_. Needles are made in accordance with each method of +dividing the _bes_. According to the first method, to the number of +twenty-four half _nummi_; according to the second method, to the number +of thirty-one half _semunciae_, that is to say a _sicilicus_; for if the +needles were made to the number of the smaller weights, the number of +needles would again be too large, and not a few of them, by reason of +the small difference in proportion of silver or copper, would have no +significance. We test both bars and coined money composed of silver and +copper by both scales. The one is as follows: the first needle is made +of twenty-three parts of copper and one part silver; whereby, whatsoever +bar or coin, when rubbed on the touchstone, colours it just as this +needle does, in that bar or money there is one twenty-fourth part of +silver, and so also, in accordance with the proportion of silver, is +known the remaining proportion of the copper. + + The 1st needle is made of 23 parts of copper and 1 of silver. + " 2nd " " 22 " " 2 " + " 3rd " " 21 " " 3 " + " 4th " " 20 " " 4 " + " 5th " " 19 " " 5 " + " 6th " " 18 " " 6 " + " 7th " " 17 " " 7 " + " 8th " " 16 " " 8 " + " 9th " " 15 " " 9 " + " 10th " " 14 " " 10 " + " 11th " " 13 " " 11 " + " 12th " " 12 " " 12 " + " 13th " " 11 " " 13 " + " 14th " " 10 " " 14 " + " 15th " " 9 " " 15 " + " 16th " " 8 " " 16 " + " 17th " " 7 " " 17 " + " 18th " " 6 " " 18 " + " 19th " " 5 " " 19 " + " 20th " " 4 " " 20 " + " 21st " " 3 " " 21 " + " 22nd " " 2 " " 22 " + " 23rd " " 1 " " 23 " + " 24th of pure silver. + +The other method of making needles is as follows:-- + + Copper. Silver. + _Semunciae_ _Sicilici._ _Semunciae_ _Sicilici._ + + The 1st is of 15 1 + " 2nd " " 14 1 1 1 + " 3rd " " 14 2 + + " 4th " " 13 1 2 1 + " 5th " " 13 3 + " 6th " " 12 1 3 1 + + " 7th " " 12 4 + " 8th " " 11 1 4 1 + " 9th " " 11 5 + + " 10th " " 10 1 5 1 + " 11th " " 10 6 + " 12th " " 9 1 6 1 + + " 13th " " 9 7 + " 14th " " 8 1 7 1 + " 15th " " 8 8 + + " 16th " " 7 1 8 1 + " 17th " " 7 9 + " 18th " " 6 1 9 1 + + " 19th " " 6 10 + " 20th " " 5 1 10 1 + " 21st " " 5 11 + + " 22nd " " 4 1 11 1 + " 23rd " " 4 12 + " 24th " " 3 1 12 1 + + " 25th " " 3 13 + " 26th " " 2 1 13 1 + " 27th " " 2 14 + + " 28th " " 1 1 14 1 + " 29th " " 1 15 + " 30th " " 1 15 1 + " 31st of pure silver. + +So much for this. Perhaps I have used more words than those most highly +skilled in the art may require, but it is necessary for the +understanding of these matters. + +I will now speak of the weights, of which I have frequently made +mention. Among mining people these are of two kinds, that is, the +greater weights and the lesser weights. The _centumpondium_ is the first +and largest weight, and of course consists of one hundred _librae_, and +for that reason is called a hundred weight. + +The various weights are:-- + + 1st = 100 _librae_ = _centumpondium_. + 2nd = 50 " + 3rd = 25 " + 4th = 16 " + 5th = 8 " + 6th = 4 " + 7th = 2 " + 8th = 1 _libra_. + +This _libra_ consists of sixteen _unciae_, and the half part of the +_libra_ is the _selibra_, which our people call a _mark_, and consists +of eight _unciae_, or, as they divide it, of sixteen _semunciae_:-- + + 9th = 8 _unciae_. + 10th = 8 _semunciae_. + 11th = 4 " + 12th = 2 " + 13th = 1 _semuncia_. + 14th = 1 _sicilicus_. + 15th = 1 _drachma_. + 16th = 1 _dimidi-drachma_. + +[Illustration 262 (Weights for Assay Balances)] + +The above is how the "greater" weights are divided. The "lesser" weights +are made of silver or brass or copper. Of these, the first and largest +generally weighs one _drachma_, for it is necessary for us to weigh, not +only ore, but also metals to be assayed, and smaller quantities of lead. +The first of these weights is called a _centumpondium_ and the number of +_librae_ in it corresponds to the larger scale, being likewise one +hundred[42]. + + The 1st is called 1 _centumpondium_. + " 2nd " 50 _librae_. + " 3rd " 25 " + " 4th " 16 " + " 5th " 8 " + " 6th " 4 " + " 7th " 2 " + " 8th " 1 " + " 9th " 1 _selibra_. + " 10th " 8 _semunciae_. + " 11th " 4 " + " 12th " 2 " + " 13th " 1 " + " 14th " 1 _sicilicus_. + +The fourteenth is the last, for the proportionate weights which +correspond with a _drachma_ and half a _drachma_ are not used. On all +these weights of the lesser scale, are written the numbers of _librae_ +and of _semunciae_. Some copper assayers divide both the lesser and +greater scale weights into divisions of a different scale. Their largest +weight of the greater scale weighs one hundred and twelve _librae_, +which is the first unit of measurement. + + 1st = 112 _librae_. + 2nd = 64 " + 3rd = 32 " + 4th = 16 " + 5th = 8 " + 6th = 4 " + 7th = 2 " + 8th = 1 " + 9th = 1 _selibra_ or sixteen _semunciae_. + 10th = 8 _semunciae_. + 11th = 4 " + 12th = 2 " + 13th = 1 " + +As for the _selibra_ of the lesser weights, which our people, as I have +often said, call a _mark_, and the Romans call a _bes_, coiners who coin +gold, divide it just like the greater weights scale, into twenty-four +units of two _sextulae_ each, and each unit of two _sextulae_ is divided +into four _semi-sextulae_ and each _semi-sextula_ into three units of +four _siliquae_ each. Some also divide the separate units of four +_siliquae_ into four individual _siliquae_, but most, omitting the +_semi-sextulae_, then divide the double _sextula_ into twelve units of +four _siliquae_ each, and do not divide these into four individual +_siliquae_. Thus the first and greatest unit of measurement, which is +the _bes_, weighs twenty-four double _sextulae_. + + The 2nd = 12 double _sextulae_. + " 3rd = 6 " " + " 4th = 3 " " + " 5th = 2 " " + " 6th = 1 " " + " 7th = 2 _semi-sextulae_ or four _semi-sextulae_. + " 8th = 1 _semi-sextula_ or 3 units of 4 _siliquae_ each. + " 9th = 2 units of four _siliquae_ each. + " 10th = 1 " " " + +Coiners who mint silver also divide the _bes_ of the lesser weights in +the same way as the greater weights; our people, indeed, divide it into +sixteen _semunciae_, and the _semuncia_ into eighteen units of four +_siliquae_ each. + +There are ten weights which are placed in the other pan of the balance, +when they weigh the silver which remains from the copper that has been +consumed, when they assay the alloy with fire. + + The 1st = 16 _semunciae_ = 1 _bes_. + " 2nd = 8 " + " 3rd = 4 " + " 4th = 2 " + " 5th = 1 " or 18 units of 4 _siliquae_ each. + " 6th = 9 units of 4 _siliquae_ each. + " 7th = 6 " " + " 8th = 3 " " + " 9th = 2 " " + " 10th = 1 " " + +The coiners of Nuremberg who mint silver, divide the _bes_ into sixteen +_semunciae_, but divide the _semuncia_ into four _drachmae_, and the +_drachma_ into four _pfennige_. They employ nine weights. + + The 1st = 16 _semunciae_. + " 2nd = 8 " + " 3rd = 4 " + " 4th = 2 " + " 5th = 1 " + +For they divide the _bes_ in the same way as our own people, but since +they divide the _semuncia_ into four _drachmae_, + + the 6th weight = 2 _drachmae_. + " 7th " = 1 _drachma_ or 4 _pfennige_. + " 8th " = 2 _pfennige_. + " 9th " = 1 _pfennig_. + +The men of Cologne and Antwerp[43] divide the _bes_ into twelve units of +five _drachmae_ and one _scripulum_, which weights they call _nummi_. +Each of these they again divide into twenty-four units of four +_siliquae_ each, which they call _grenlins_. They have ten weights, of +which + + the 1st = 12 _nummi_ = 1 _bes_. + " 2nd = 6 " + " 3rd = 3 " + " 4th = 2 " + " 5th = 1 " = 24 units of 4 _siliquae_ each. + " 6th = 12 units of 4 _siliquae_ each. + " 7th = 6 " " + " 8th = 3 " " + " 9th = 2 " " + " 10th = 1 " " + +And so with them, just as with our own people, the _mark_ is divided +into two hundred and eighty-eight _grenlins_, and by the people of +Nuremberg it is divided into two hundred and fifty-six _pfennige_. +Lastly, the Venetians divide the _bes_ into eight _unciae_. The _uncia_ +into four _sicilici_, the _sicilicus_ into thirty-six _siliquae_. They +make twelve weights, which they use whenever they wish to assay alloys +of silver and copper. Of these + + the 1st = 8 _unciae_ = 1 _bes_. + " 2nd = 4 " + " 3rd = 2 " + " 4th = 1 " or 4 _sicilici_. + " 5th = 2 _sicilici_. + " 6th = 1 _sicilicus_. + " 7th = 18 _siliquae_. + " 8th = 9 " + " 9th = 6 " + " 10th = 3 " + " 11th = 2 " + " 12th = 1 " + +Since the Venetians divide the _bes_ into eleven hundred and fifty-two +_siliquae_, or two hundred and eighty-eight units of 4 _siliquae_ each, +into which number our people also divide the _bes_, they thus make the +same number of _siliquae_, and both agree, even though the Venetians +divide the _bes_ into smaller divisions. + +This, then, is the system of weights, both of the greater and the lesser +kinds, which metallurgists employ, and likewise the system of the lesser +weights which coiners and merchants employ, when they are assaying +metals and coined money. The _bes_ of the larger weight with which they +provide themselves when they weigh large masses of these things, I have +explained in my work _De Mensuris et Ponderibus_, and in another book, +_De Precio Metallorum et Monetis_. + +[Illustration 265 (Balances): A--First small balance. B--Second. +C--Third, placed in a case.] + +There are three small balances by which we weigh ore, metals, and +fluxes. The first, by which we weigh lead and fluxes, is the largest +among these smaller balances, and when eight _unciae_ (of the greater +weights) are placed in one of its pans, and the same number in the +other, it sustains no damage. The second is more delicate, and by this +we weigh the ore or the metal, which is to be assayed; this is well able +to carry one _centumpondium_ of the lesser weights in one pan, and in +the other, ore or metal as heavy as that weight. The third is the most +delicate, and by this we weigh the beads of gold or silver, which, when +the assay is completed, settle in the bottom of the cupel. But if anyone +weighs lead in the second balance, or an ore in the third, he will do +them much injury. + +Whatsoever small amount of metal is obtained from a _centumpondium_ of +the lesser weights of ore or metal alloy, the same greater weight of +metal is smelted from a _centumpondium_ of the greater weight of ore or +metal alloy. + + END OF BOOK VII. + + +FOOTNOTES: + +[1] We have but little record of anything which could be called +"assaying" among the Greeks and Romans. The fact, however, that they +made constant use of the touchstone (see note 37, p. 252) is sufficient +proof that they were able to test the purity of gold and silver. The +description of the touchstone by Theophrastus contains several +references to "trial" by fire (see note 37, p. 252). They were adepts at +metal working, and were therefore familiar with melting metals on a +small scale, with the smelting of silver, lead, copper, and tin ores +(see note 1, p. 353) and with the parting of silver and lead by +cupellation. Consequently, it would not require much of an imaginative +flight to conclude that there existed some system of tests of ore and +metal values by fire. Apart from the statement of Theophrastus referred +to, the first references made to anything which might fill the _rôle_ of +assaying are from the Alchemists, particularly Geber (prior to 1300), +for they describe methods of solution, precipitation, distillation, +fusing in crucibles, cupellation, and of the parting of gold and silver +by acid and by sulphur, antimony, or cementation. However, they were not +bent on determining quantitative values, which is the fundamental object +of the assayer's art, and all their discussion is shrouded in an obscure +cloak of gibberish and attempted mysticism. Nevertheless, therein lies +the foundation of many cardinal assay methods, and even of chemistry +itself. + +The first explicit records of assaying are the anonymous booklets +published in German early in the 16th Century under the title +_Probierbüchlein_. Therein the art is disclosed well advanced toward +maturity, so far as concerns gold and silver, with some notes on lead +and copper. We refer the reader to Appendix B for fuller discussion of +these books, but we may repeat here that they are a collection of +disconnected recipes lacking in arrangement, the items often repeated, +and all apparently the inheritance of wisdom passed from father to son +over many generations. It is obviously intended as a sort of reminder to +those already skilled in the art, and would be hopeless to a novice. +Apart from some notes in Biringuccio (Book III, Chaps. 1 and 2) on +assaying gold and silver, there is nothing else prior to _De Re +Metallica_. Agricola was familiar with these works and includes their +material in this chapter. The very great advance which his account +represents can only be appreciated by comparison, but the exhaustive +publication of other works is foreign to the purpose of these notes. +Agricola introduces system into the arrangement of his materials, +describes implements, and gives a hundred details which are wholly +omitted from the previous works, all in a manner which would enable a +beginner to learn the art. Furthermore, the assaying of lead, copper, +tin, quicksilver, iron, and bismuth, is almost wholly new, together with +the whole of the argument and explanations. We would call the attention +of students of the history of chemistry to the general oversight of +these early 16th Century attempts at analytical chemistry, for in them +lie the foundations of that science. The statement sometimes made that +Agricola was the first assayer, is false if for no other reason than +that science does not develop with such strides at any one human hand. +He can, however, fairly be accounted as the author of the first proper +text-book upon assaying. Those familiar with the art will be astonished +at the small progress made since his time, for in his pages appear most +of the reagents and most of the critical operations in the dry analyses +of gold, silver, lead, copper, tin, bismuth, quicksilver, and iron of +to-day. Further, there will be recognised many of the "kinks" of the art +used even yet, such as the method of granulation, duplicate assays, the +"assay ton" method of weights, the use of test lead, the introduction of +charges in leaf lead, and even the use of beer instead of water to damp +bone-ash. + +The following table is given of the substances mentioned requiring some +comment, and the terms adopted in this book, with notes for convenience +in reference. The German terms are either from Agricola's Glossary of +_De Re Metallica_, his _Interpretatio_, or the German Translation. We +have retained the original German spelling. The fifth column refers to +the page where more ample notes are given:-- + + Terms Latin. German. Remarks. Further + adopted. Notes. + + Alum _Alumen_ _Alaun_ Either potassium p. 564 + or ammonia alum + + Ampulla _Ampulla_ _Kolb_ A distillation jar + + Antimony _Stibium_ _Spiesglas_ Practically always p. 428 + antimony sulphide + + _Aqua valens_ _Aqua valens_ _Scheidewasser_ Mostly nitric acid p. 439 + or _aqua_ + + Argol _Feces vini _Die Crude tartar p. 234 + siccae_ weinheffen_ + + Ash of lead _Nigrum Artificial lead p. 237 + plumbum sulphide + cinereum_ + + Ash of musk ivy _Sal ex _Salalkali_ Mostly potash p. 560 + (Salt made anthyllidis + from) cinere factus_ + + Ashes which _Cineres quo Mostly potash p. 559 + wool-dyers use infectores + lanarum + utuntur_ + + Assay _Venas experiri_ _Probiren_ + + Assay furnace _Fornacula_ _Probir ofen_ "Little" furnace + + Azure _Caeruleum_ _Lasur_ Partly copper p. 110 + carbonate + (azurite) + partly silicate + + Bismuth _Plumbum _Wismut_ _Bismuth_ p. 433 + Cinereum_ + + Bitumen _Bitumen_ _Bergwachs_ p. 581 + + Blast furnace _Prima fornax_ _Schmeltzofen_ + + Borax _Chrysocolla ex _Borras; Tincar_ p. 560 + nitro + confecta; + chrysocolla + quam boracem + nominant_ + + Burned alum _Alumen coctum_ _Gesottener Probably p. 565 + alaun_ dehydrated alum + + _Cadmia_ (1) Furnace p. 112 + (see note accretions (2) + 8, p. 112) Calamine (3) Zinc + blende (4) Cobalt + arsenical sulphides + + Camphor _Camphora_ _Campffer_ p. 238 + + Chrysocolla + called borax + (see borax) + + Chrysocolla _Chrysocolla_ _Berggrün und Partly p. 110 + (copper Schifergrün_ chrysocolla, + mineral) partly malachite + + Copper filings _Aeris scobs _Kupferfeilich_ Apparently finely p. 233 + elimata_ divided copper + metal + + Copper flowers _Aeris flos_ _Kupferbraun_ Cupric oxide p. 538 + + Copper scales _Aeris squamae_ _Kupfer Probably cupric + hammerschlag oxide + oder kessel + braun_ + + Copper + minerals (see + note 8, + p. 109) + + Crucible _Catillus _Dreieckicht- See illustration p. 229 + (triangular) triangularis_ schirbe_ + + Cupel _Catillus _Capelle_ + cinereus_ + + Cupellation _Secunda _Treibherd_ + furnace fornax_ + + Flux _Additamentum_ _Zusetze_ p. 232 + + Furnace _Cadmia _Mitlere und + accretions fornacum_ obere + offenbrüche_ + + Galena _Lapis _Glantz_ Lead sulphide p. 110 + plumbarius_ + + Glass-gall _Recrementum _Glassgallen_ Skimmings from p. 235 + vitri_ glass melting + + Grey antimony or _Stibi_ or _Spiesglas_ Antimony sulphide, p. 428 + stibium _stibium_ stibnite + + Hearth-lead _Molybdaena_ _Herdplei_ The saturated p. 476 + furnace bottoms + from cupellation + + Hoop (iron) _Circulus _Ring_ A forge for p. 226 + ferreus_ crucibles + + Iron filings _Ferri scobs _Eisen feilich_ Metallic iron + elimata_ + + Iron scales _Squamae ferri_ _Eisen Partly iron oxide + hammerschlag_ + + Iron slag _Recrementum _Sinder_ + ferri_ + + Lead ash _Cinis plumbi _Pleiasche_ Artificial lead p. 237 + nigri_ sulphide + + Lead granules _Globuli _Gekornt plei_ Granulated lead + plumbei_ + + Lead ochre _Ochra _Pleigeel_ Modern massicot p. 232 + plumbaria_ (PbO) + + Lees of _aqua_ _Feces aquarum _Scheidewasser Uncertain p. 234 + which separates quae aurum ab heffe_ + gold from argento + silver secernunt_ + + Dried lees of _Siccae feces _Heffe des Argol p. 234 + vinegar aceti_ essigs_ + + Dried lees of _Feces vini _Wein heffen_ Argol p. 234 + wine siccae_ + + Limestone _Saxum calcis_ _Kalchstein_ + + Litharge _Spuma argenti_ _Glette_ + + Lye _Lixivium_ _Lauge durch Mostly potash p. 233 + asschen + gemacht_ + + Muffle _Tegula_ _Muffel_ Latin, literally + "Roof-tile" + + Operculum _Operculum_ _Helm oder Helmet or cover + alembick_ for a distillation + jar + + Orpiment _Auripigmentum_ _Operment_ Yellow sulphide p. 111 + of arsenic + (As_{2}S_{3}) + + Pyrites _Pyrites_ _Kis_ Rather a genus p. 112 + of sulphides, + than iron + pyrite in + particular + + Pyrites (Cakes _Panes ex _Stein_ Iron or Copper p. 350 + from) pyrite matte + conflati_ + + Realgar _Sandaraca_ _Rosgeel_ Red sulphide of p. 111 + arsenic (AsS) + + Red lead _Minium_ _Menning_ Pb_{3}O_{4} p. 232 + + Roasted copper _Aes ustum_ _Gebrandt Artificial p. 233 + kupffer_ copper + sulphide (?) + + Salt _Sal_ _Saltz_ NaCl p. 233 + + Salt (Rock) _Sal fossilis_ _Berg saltz_ NaCl p. 233 + + _Sal _Sal A stock flux? p. 236 + artificiosus_ artificiosus_ + + Sal ammoniac _Sal _Salarmoniac_ NH_{4}Cl p. 560 + ammoniacus_ + + Saltpetre _Halinitrum_ _Salpeter_ KNO_{3} p. 561 + + Salt (refined) _Sal facticius NaCl + purgatus_ + + _Sal tostus_ _Sal tostus_ _Geröst saltz_ Apparently p. 233 + simply heated or + melted common + salt + + _Sal _Sal _Geröst saltz_ p. 233 + torrefactus_ torrefactus_ + + Salt (melted) _Sal _Geflossen Melted salt or p. 233 + liquefactus_ saltz_ salt glass + + Scorifier _Catillus _Scherbe_ + fictilis_ + + Schist _Saxum fissile_ _Schifer_ + + Silver minerals + (see note 8, + p. 108) + + Slag _Recrementum_ _Schlacken_ + + Soda _Nitrum_ Mostly soda from p. 558 + Egypt, + Na_{2}CO_{3} + + Stones which _Lapides qui _Flüs_ Quartz and p. 380 + easily melt facile igni fluorspar + liquescunt_ + + Sulphur _Sulfur_ _Schwefel_ p. 579 + + _Tophus_ _Tophus_ _Topstein_ Marl(?) p. 233 + + Touchstone _Coticula_ _Goldstein_ + + Venetian glass _Venetianum + vitrum_ + + Verdigris _Aerugo _Grünspan_ Copper p. 440 + oder sub-acetate + Spanschgrün_ + + Vitriol _Atramentum _Kupferwasser_ Mostly FeSO_{4} p. 572 + sutorium_ + + White schist _Saxum fissile _Weisser p. 234 + album_ schifer_ + + Weights (see + Appendix). + + +[2] _Crudorum_,--unbaked? + +[3] This reference is not very clear. Apparently the names refer to the +German terms _probier ofen_ and _windt ofen_. + +[4] _Circulus_. This term does not offer a very satisfactory equivalent, +as such a furnace has no distinctive name in English. It is obviously a +sort of forge for fusing in crucibles. + +[5] _Spissa_,--"Dry." This term is used in contra-distinction to +_pingue_, unctuous or "fatty." + +[6] _Additamenta_,--"Additions." Hence the play on words. + +We have adopted "flux" because the old English equivalent for all these +materials was "flux," although in modern nomenclature the term is +generally restricted to those substances which, by chemical combination +in the furnace, lower the melting point of some of the charge. The +"additions" of Agricola, therefore, include reducing, oxidizing, +sulphurizing, desulphurizing, and collecting agents as well as fluxes. A +critical examination of the fluxes mentioned in the next four pages +gives point to the Author's assertion that "some are of a very +complicated nature." However, anyone of experience with home-taught +assayers has come in contact with equally extraordinary combinations. +The four orders of "additions" enumerated are quite impossible to +reconcile from a modern metallurgical point of view. + +[7] _Minium secundarium_. (_Interpretatio_,--_menning_. Pb_{3}O_{4}). +Agricola derived his Latin term from Pliny. There is great confusion in +the ancient writers on the use of the word _minium_, for prior to the +Middle Ages it was usually applied to vermilion derived from cinnabar. +Vermilion was much adulterated with red-lead, even in Roman times, and +finally in later centuries the name came to be appropriated to the lead +product. Theophrastus (103) mentions a substitute for vermilion, but, in +spite of commentators, there is no evidence that it was red-lead. The +first to describe the manufacture of real red-lead was apparently +Vitruvius (VII, 12), who calls it _sandaraca_ (this name was usually +applied to red arsenical sulphide), and says: "White-lead is heated in a +furnace and by the force of the fire becomes red lead. This invention +was the result of observation in the case of an accidental fire, and by +the process a much better material is obtained than from the mines." He +describes _minium_ as the product from cinnabar. Dioscorides (V, 63), +after discussing white-lead, says it may be burned until it becomes the +colour of _sandaracha_, and is called _sandyx_. He also states (V, 69) +that those are deceived who consider cinnabar to be the same as +_minium_, for _minium_ is made in Spain out of stone mixed with silver +sands. Therefore he is not in agreement with Vitruvius and Pliny on the +use of the term. Pliny (XXXIII, 40) says: "These barren stones +(apparently lead ores barren of silver) may be recognised by their +colour; it is only in the furnace that they turn red. After being +roasted it is pulverized and is _minium secundarium_. It is known to few +and is very inferior to the natural kind made from those sands we have +mentioned (_cinnabar_). It is with this that the genuine _minium_ is +adulterated in the works of the Company." This proprietary company who +held a monopoly of the Spanish quicksilver mines, "had many methods of +adulterating it (_minium_)--a source of great plunder to the Company." +Pliny also describes the making of red lead from white. + +[8] _Ochra plumbaria_. (_Interpretatio_,--_pleigeel_; modern +German,--_Bleigelb_). The German term indicates that this "Lead Ochre," +a form of PbO, is what in the English trade is known as _massicot_, or +_masticot_. This material can be a partial product from almost any +cupellation where oxidation takes place below the melting point of the +oxide. It may have been known to the Ancients among the various species +into which they divided litharge, but there is no valid reason for +assigning to it any special one of their terms, so far as we can see. + +[9] There are four forms of copper named as re-agents by Agricola: + + Copper filings _Aeris scobs elimata._ + Copper scales _Aeris squamae._ + Copper flowers _Aeris flos._ + Roasted copper _Aes ustum._ + +The first of these was no doubt finely divided copper metal; the second, +third, and fourth were probably all cupric oxide. According to Agricola +(_De Nat. Fos._, p. 352), the scales were the result of hammering the +metal; the flowers came off the metal when hot bars were quenched in +water, and a third kind were obtained from calcining the metal. "Both +flowers (_flos_) and hammer-scales (_squama_) have the same properties +as _crematum_ copper.... The particles of flower copper are finer than +scales or _crematum_ copper." If we assume that the verb _uro_ used in +_De Re Metallica_ is of the same import as _cremo_ in the _De Natura +Fossilium_, we can accept this material as being merely cupric oxide, +but the _aes ustum_ of Pliny--Agricola's usual source of technical +nomenclature--is probably an artificial sulphide. Dioscorides (V, 47), +who is apparently the source of Pliny's information, says:--"Of _chalcos +cecaumenos_, the best is red, and pulverized resembles the colour of +cinnabar; if it turns black, it is over-burnt. It is made from broken +ship nails put into a rough earthen pot, with alternate layers of equal +parts of sulphur and salt. The opening should be smeared with potter's +clay and the pot put in the furnace until it is thoroughly heated," etc. +Pliny (XXXIV, 23) states: "Moreover Cyprian copper is roasted in crude +earthen pots with an equal amount of sulphur; the apertures of the pots +are well luted, and they are kept in the furnace until the pot is +thoroughly heated. Some add salt, others use _alumen_ instead of +sulphur, others add nothing, but only sprinkle it with vinegar." + +[10] The reader is referred to note 6, p. 558, for more ample discussion +of the alkalis. Agricola gives in this chapter four substances of that +character: + + Soda (_nitrum_). Lye. "Ashes which wool-dyers use." "Salt made + from the ashes of musk ivy." + +The last three are certainly potash, probably impure. While the first +might be either potash or soda, the fact that the last three are +mentioned separately, together with other evidence, convinces us that by +the first is intended the _nitrum_ so generally imported into Europe +from Egypt during the Middle Ages. This imported salt was certainly the +natural bicarbonate, and we have, therefore, used the term "soda." + +[11] In this chapter are mentioned seven kinds of common salt: + + Salt _Sal._ + Rock salt _Sal fossilis._ + "Made" salt _Sal facticius._ + Refined salt _Sal purgatius._ + Melted salt _Sal liquefactus._ + +And in addition _sal tostus_ and _sal torrefactus_. _Sal facticius_ is +used in distinction from rock-salt. The melted salt would apparently be +salt-glass. What form the _sal tostus_ and _sal torrefactus_ could have +we cannot say, however, but they were possibly some form of heated salt; +they may have been combinations after the order of _sal artificiosus_ +(see p. 236). + +[12] "Stones which easily melt in hot furnaces and sand which is made +from them" (_lapides qui in ardentibus fornacibus facile liquescunt +arenae ab eis resolutae_). These were probably quartz in this instance, +although fluorspar is also included in this same genus. For fuller +discussion see note on p. 380. + +[13] _Tophus_. (_Interpretatio_, _Toffstein oder topstein_). According +to Dana (Syst. of Min., p. 678), the German _topfstein_ was English +potstone or soapstone, a magnesian silicate. It is scarcely possible, +however, that this is what Agricola meant by this term, for such a +substance would be highly infusible. Agricola has a good deal to say +about this mineral in _De Natura Fossilium_ (p. 189 and 313), and from +these descriptions it would seem to be a tufaceous limestone of various +sorts, embracing some marls, stalagmites, calcareous sinter, etc. He +states: "Generally fire does not melt it, but makes it harder and breaks +it into powder. Tophus is said to be a stone found in caverns, made from +the dripping of stone juice solidified by cold ... sometimes it is found +containing many shells, and likewise the impressions of alder leaves; +our people make lime by burning it." Pliny, upon whom Agricola depends +largely for his nomenclature, mentions such a substance (XXXVI, 48): +"Among the multitude of stones there is _tophus_. It is unsuitable for +buildings, because it is perishable and soft. Still, however, there are +some places which have no other, as Carthage, in Africa. It is eaten +away by the emanations from the sea, crumbled to dust by the wind, and +washed away by the rain." In fact, _tophus_ was a wide genus among the +older mineralogists, Wallerius (_Meditationes Physico-Chemicae De +Origine Mundi_, Stockholm, 1776, p. 186), for instance, gives 22 +varieties. For the purposes for which it is used we believe it was +always limestone of some form. + +[14] _Saxum fissile album._ (_The Interpretatio_ gives the German as +_schifer_). Agricola mentions it in _Bermannus_ (459), in _De Natura +Fossilium_ (p. 319), but nothing definite can be derived from these +references. It appears to us from its use to have been either a +quartzite or a fissile limestone. + +[15] Argol (_Feces vini siccae_,--"Dried lees of wine." Germ. trans. +gives _die wein heffen_, although the usual German term of the period +was _weinstein_). The lees of wine were the crude tartar or argols of +commerce and modern assayers. The argols of white wine are white, while +they are red from red wine. The white argol which Agricola so often +specifies would have no special excellence, unless it may be that it is +less easily adulterated. Agricola (_De Nat. Fos._, p. 344) uses the +expression "_Fex vini sicca_ called _tartarum_"--one of the earliest +appearances of the latter term in this connection. The use of argol is +very old, for Dioscorides (1st Century A.D.) not only describes argol, +but also its reduction to impure potash. He says (V, 90): "The lees +(_tryx_) are to be selected from old Italian wine; if not, from other +similar wine. Lees of vinegar are much stronger. They are carefully +dried and then burnt. There are some who burn them in a new earthen pot +on a large fire until they are thoroughly incinerated. Others place a +quantity of the lees on live coals and pursue the same method. The test +as to whether it is completely burned, is that it becomes white or blue, +and seems to burn the tongue when touched. The method of burning lees of +vinegar is the same.... It should be used fresh, as it quickly grows +stale; it should be placed in a vessel in a secluded place." Pliny +(XXIII, 31) says: "Following these, come the lees of these various +liquids. The lees of wine (_vini faecibus_) are so powerful as to be +fatal to persons on descending into the vats. The test for this is to +let down a lamp, which, if extinguished, indicates the peril.... Their +virtues are greatly increased by the action of fire." Matthioli, +commenting on this passage from Dioscorides in 1565, makes the following +remark (p. 1375): "The precipitate of the wine which settles in the +casks of the winery forms stone-like crusts, and is called by the +works-people by the name _tartarum_." It will be seen above that these +lees were rendered stronger by the action of fire, in which case the +tartar was reduced to potassium carbonate. The _weinstein_ of the old +German metallurgists was often the material lixiviated from the +incinerated tartar. + +Dried lees of vinegar (_siccae feces aceti_; _Interpretatio_, _die heffe +des essigs_). This would also be crude tartar. Pliny (XXIII, 32) says: +"The lees of vinegar (_faex aceti_); owing to the more acrid material +are more aggravating in their effects.... When combined with +_melanthium_ it heals the bites of dogs and crocodiles." + +[16] Dried lees of _aqua_ which separates gold and silver. (_Siccae +feces aquarum quae aurum ab argento secernunt_. German translation, _Der +scheidwasser heffe_). There is no pointed description in Agricola's +works, or in any other that we can find, as to what this material was. +The "separating _aqua_" was undoubtedly nitric acid (see p. 439, Book +X). There are two precipitates possible, both referred to as +_feces_,--the first, a precipitate of silver chloride from clarifying +the _aqua valens_, and the second, the residues left in making the acid +by distillation. It is difficult to believe that silver chloride was the +_feces_ referred to in the text, because such a precipitate would be +obviously misleading when used as a flux through the addition of silver +to the assays, too expensive, and of no merit for this purpose. +Therefore one is driven to the conclusion that the _feces_ must have +been the residues left in the retorts when nitric acid was prepared. It +would have been more in keeping with his usual mode of expression, +however, to have referred to this material as a _residuus_. The +materials used for making acid varied greatly, so there is no telling +what such a _feces_ contained. A list of possibilities is given in note +8, p. 443. In the main, the residue would be undigested vitriol, alum, +saltpetre, salt, etc., together with potassium, iron, and alum +sulphates. The _Probierbüchlin_ (p. 27) also gives this re-agent under +the term _Toden kopff das ist schlam oder feces auss dem scheydwasser_. + +[17] _Recrementum vitri_. (_Interpretatio_, _Glassgallen_). Formerly, +when more impure materials were employed than nowadays, the surface of +the mass in the first melting of glass materials was covered with salts, +mostly potassium and sodium sulphates and chlorides which escaped +perfect vitrification. This "slag" or "_glassgallen_" of Agricola was +also termed _sandiver_. + +[18] The whole of this expression is "_candidus, candido_." It is by no +means certain that this is tin, for usually tin is given as _plumbum +candidum_. + +[19] _Sal artificiosus_. These are a sort of stock fluxes. Such mixtures +are common in all old assay books, from the _Probierbüchlin_ to later +than John Cramer in 1737 (whose Latin lectures on Assaying were +published in English under the title of "Elements of the Art of Assaying +Metals," London, 1741). Cramer observes (p. 51) that: "Artificers +compose a great many fluxes with the above-mentioned salts and with the +reductive ones; nay, some use as many different fluxes as there are +different ores and metals; all which, however, we think needless to +describe. It is better to have explained a few of the simpler ones, +which serve for all the others, and are very easily prepared, than to +tire the reader with confused compositions: and this chiefly because +unskilled artificers sometimes attempt to obtain with many ingredients +of the same nature heaped up beyond measure, and with much labour, +though not more properly and more securely, what might have been easily +effected, with one only and the same ingredient, thus increasing the +number, not at all the virtue of the things employed. Nevertheless, if +anyone loves variety, he may, according to the proportions and cautions +above prescribed, at his will chuse among the simpler kinds such as will +best suit his purpose, and compose a variety of fluxes with them." + +[20] This operation apparently results in a coating to prevent the +deflagration of the saltpetre--in fact, it might be permitted to +translate _inflammatur_ "deflagrate," instead of kindle. + +[21] The results which would follow from the use of these "fluxes" would +obviously depend upon the ore treated. They can all conceivably be +successful. Of these, the first is the lead-glass of the German +assayers--a flux much emphasized by all old authorities, including +Lohneys, Ercker and Cramner, and used even yet. The "powerful flux" +would be a reducing, desulphurizing, and an acid flux. The "more +powerful" would be a basic flux in which the reducing action of the +argols would be largely neutralised by the nitre. The "still more +powerful" would be a strongly sulphurizing basic flux, while the "most +powerful" would be a still more sulphurizing flux, but it is badly mixed +as to its oxidation and basic properties. (See also note 19 on _sal +artificiosus_). + +[22] Lead ash (_Cinis Plumbi_. Glossary, _Pleyasch_).--This was +obviously, from the method of making, an artificial lead sulphide. + +[23] Ashes of lead (_Nigri plumbi cinis_). This, as well as lead ash, +was also an artificial lead sulphide. Such substances were highly valued +by the Ancients for medicinal purposes. Dioscorides (V, 56) says: +"Burned lead (_Molybdos cecaumenos_) is made in this way: Sprinkle +sulphur over some very thinnest lead plates and put them into a new +earthen pot, add other layers, putting sulphur between each layer until +the pot is full; set it alight and stir the melted lead with an iron rod +until it is entirely reduced to ashes and until none of the lead remains +unburned. Then take it off, first stopping up your nose, because the +fumes of burnt lead are very injurious. Or burn the lead filings in a +pot with sulphur as aforesaid." Pliny (XXXIV., 50) gives much the same +directions. + +[24] Camphor (_camphora_). This was no doubt the well-known gum. +Agricola, however, believed that camphor (_De Nat. Fossilium_, p. 224) +was a species of bitumen, and he devotes considerable trouble to the +refutation of the statements by the Arabic authors that it was a gum. In +any event, it would be a useful reducing agent. + +[25] Inasmuch as orpiment and realgar are both arsenical sulphides, the +use of iron "slag," if it contains enough iron, would certainly matte +the sulphur and arsenic. Sulphur and arsenic are the "juices" referred +to (see note 4, p. 1). It is difficult to see the object of preserving +the antimony with such a sulphurizing "addition," unless it was desired +to secure a regulus of antimony alone from a given antimonial ore. + +[26] The lead free from silver, called _villacense_, was probably from +Bleyberg, not far from Villach in Upper Austria, this locality having +been for centuries celebrated for its pure lead. These mines were worked +prior to, and long after, Agricola's time. + +[27] This method of proportionate weights for assay charges is simpler +than the modern English "assay ton," both because of the use of 100 +units in the standard of weight (the _centumpondium_), and because of +the lack of complication between the Avoirdupois and Troy scales. For +instance, an ore containing a _libra_ of silver to the _centumpondium_ +would contain 1/100th part, and the same ratio would obtain, no matter +what the actual weight of a _centumpondium_ of the "lesser weight" might +be. To follow the matter still further, an _uncia_ being 1/1,200 of a +_centumpondium_, if the ore ran one "_uncia_ of the lesser weight" to +the "_centumpondium_ of the lesser weight," it would also run one actual +_uncia_ to the actual _centumpondium_; it being a matter of indifference +what might be the actual weight of the _centumpondium_ upon which the +scale of lesser weights is based. In fact Agricola's statement (p. 261) +indicates that it weighed an actual _drachma_. We have, in some places, +interpolated the expressions "lesser" and "greater" weights for clarity. + +This is not the first mention of this scheme of lesser weights, as it +appears in the _Probierbüchlein_ (1500? see Appendix B) and Biringuccio +(1540). For a more complete discussion of weights and measures see +Appendix C. For convenience, we repeat here the Roman scale, although, +as will be seen in the Appendix, Agricola used the Latin terms in many +places merely as nomenclature equivalents of the old German scale. + + Ozs. + dwts. + Troy gr. + Grains. per short ton. + 1 _Siliqua_ 2.87 Per _Centumpondium_ 0 3 9 + 6 _Siliquae_ = 1 _Scripulum_ 17.2 " " 1 0 6 + 4 _Scripula_ = 1 _Sextula_ 68.7 " " 4 1 0 + 6 _Sextulae_ = 1 _Uncia_ 412.2 " " 24 6 2 + 12 _Unciae_ = 1 _Libra_ 4946.4 " " 291 13 8 + 100 _Librae_ = 1 _Centumpondium_ 494640.0 + +However Agricola may occasionally use + + 16 _Unciae_ = 1 _Libra_ 6592.0 (?) + 100 _Librae_ = 1 _Centumpondium_ 659200.0 (?) + +Also + + Oz. + dwts. + gr. + per short ton. + 1 _Scripulum_ 17.2 Per _Centumpondium_ 1 0 6 + 3 _Scripula_ = 1 _Drachma_ 51.5 " " 3 0 19 + 2 _Drachmae_ = 1 _Sicilicus_ 103.0 " " 6 1 15 + 4 _Sicilici_ = 1 _Uncia_ 412.2 " " 24 6 12 + 8 _Unciae_ = 1 _Bes_ 3297.6 " " 194 12 0 + +[28] The amalgamation of gold ores is fully discussed in note 12, p. +297. + +[29] For discussion of the silver ores, see note 8, p. 108. _Rudis_ +silver was a fairly pure silver mineral, the various coloured silvers +were partly horn-silver and partly alteration products. + +[30] It is difficult to see why copper scales (_squamae aeris_--copper +oxide?) are added, unless it be to collect a small ratio of copper in +the ore. This additional copper is not mentioned again, however. The +whole of this statement is very confused. + +[31] This old story runs that Hiero, King of Syracuse, asked Archimedes +to tell him whether a crown made for him was pure gold or whether it +contained some proportion of silver. Archimedes is said to have puzzled +over it until he noticed the increase in water-level upon entering his +bath. Whereupon he determined the matter by immersing bars of pure gold +and pure silver, and thus determining the relative specific weights. The +best ancient account of this affair is to be found in Vitruvius, IX, +Preface. The story does not seem very probable, seeing that +Theophrastus, who died the year Archimedes was born, described the +touchstone in detail, and that it was of common knowledge among the +Greeks before (see note 37). In any event, there is not sufficient +evidence in this story on which to build the conclusion of Meyer (Hist. +of Chemistry, p. 14) and others, that, inasmuch as Archimedes was unable +to solve the problem until his discovery of specific weights, therefore +the Ancients could not part gold and silver. The probability that he did +not want to injure the King's jewellery would show sufficient reason for +his not parting these metals. It seems probable that the Ancients did +part gold and silver by cementation. (See note on p. 458). + +[32] The Alchemists (with whose works Agricola was familiar--_vide_ +preface) were the inventors of nitric acid separation. (See note on p. +460). + +[33] Parting gold and silver by nitric acid is more exhaustively +discussed in Book X. and note 10, p. 443. + +[34] The lesser weights, probably. + +[35] Lead and Tin seem badly mixed in this paragraph. + +[36] It is not clear what is added. + +[37] HISTORICAL NOTE ON TOUCHSTONE. (_Coticula_. +_Interpretatio_,--_Goldstein_). Theophrastus is, we believe, the first +to describe the touchstone, although it was generally known to the +Greeks, as is evidenced by the metaphors of many of the poets,--Pindar, +Theognis, Euripides, etc. The general knowledge of the constituents of +alloys which is implied, raises the question as to whether the Greeks +did not know a great deal more about parting metals, than has been +attributed to them. Theophrastus says (78-80): "The nature of the stone +which tries gold is also very wonderful, as it seems to have the same +power with fire; which is also a test of that metal. Some people have +for this reason questioned the truth of this power in the stone, but +their doubts are ill-founded, for this trial is not of the same nature +or made in the same manner as the other. The trial by fire is by the +colour and by the quantity lost by it; but that by the stone is made +only by rubbing the metal on it; the stone seeming to have the power to +receive separately the distinct particles of different metals. It is +said also that there is a much better kind of this stone now found out, +than that which was formerly used; insomuch that it now serves not only +for the trial of refined gold, but also of copper or silver coloured +with gold; and shows how much of the adulterating matter by weight is +mixed with gold; this has signs which it yields from the smallest weight +of the adulterating matter, which is a grain, from thence a colybus, and +thence a quadrans or semi-obolus, by which it is easy to distinguish if, +and in what degree, that metal is adulterated. All these stones are +found in the River Tmolus; their texture is smooth and like that of +pebbles; their figure broad, not round; and their bigness twice that of +the common larger sort of pebbles. In their use in the trial of metals +there is a difference in power between their upper surface, which has +lain toward the sun, and their under, which has been to the earth; the +upper performing its office the more nicely; and this is consonant to +reason, as the upper part is dryer; for the humidity of the other +surface hinders its receiving so well the particles of metals; for the +same reason also it does not perform its office as well in hot weather +as in colder, for in the hot it emits a kind of humidity out of its +substance, which runs all over it. This hinders the metalline particles +from adhering perfectly, and makes mistakes in the trials. This +exudation of a humid matter is also common to many other stones, among +others, to those of which statues are made; and this has been looked on +as peculiar to the statue." (Based on Hill's trans.) This humid +"exudation of fine-grained stones in summer" would not sound abnormal if +it were called condensation. Pliny (XXXIII, 43) says: "The mention of +gold and silver should be accompanied by that of the stone called +_coticula_. Formerly, according to Theophrastus, it was only to be found +in the river Tmolus but now found in many parts, it was found in small +pieces never over four inches long by two broad. That side which lay +toward the sun is better than that toward the ground. Those experienced +with the _coticula_ when they rub ore (_vena_) with it, can at once say +how much gold it contains, how much silver or copper. This method is so +accurate that they do not mistake it to a scruple." This purported use +for determining values of _ore_ is of about Pliny's average accuracy. +The first detailed account of touch-needles and their manner of making, +which we have been able to find, is that of the _Probierbüchlein_ (1527? +see Appendix) where many of the tables given by Agricola may be found. + +[38] _De Natura Fossilium_ (p. 267) and _De Ortu et Causis +Subterraneorum_ (p. 59). The author does not add any material +mineralogical information to the quotations from Theophrastus and Pliny +given above. + +[39] In these tables Agricola has simply adopted Roman names as +equivalents of the old German weights, but as they did not always +approximate in proportions, he coined terms such as "units of 4 +_siliquae_," etc. It might seem more desirable to have introduced the +German terms into this text, but while it would apply in this instance, +as we have discussed on p. 259, the actual values of the Roman weights +are very different from the German, and as elsewhere in the book actual +Roman weights are applied, we have considered it better to use the Latin +terms consistently throughout. Further, the obsolete German would be to +most readers but little improvement upon the Latin. For convenience of +readers we set out the various scales as used by Agricola, together with +the German:-- + + ROMAN SCALE. OLD GERMAN SCALE. + 6 _Siliquae_ = 1 _Scripulum_ 3 _Grenlin_ = 1 _Gran_ + 4 _Scripula_ = 1 _Sextula_ 4 _Gran_ = 1 _Krat_ + 2 _Sextulae_ = 1 _Duella_ 24 _Kratt_ = 1 _Mark_ + 24 _Duellae_ = 1 _Bes_ or + 24 _Grenlin_ = 1 "_Nummus_" + 12 "_Nummi_" = 1 _Mark_ + +Also the following scales are applied to fineness by Agricola:-- + + 3 _Scripula_ = 1 _Drachma_ 4 _Pfennige_ = 1 _Quintlein_ + 2 _Drachmae_ = 1 _Sicilicus_ 4 _Quintlein_ = 1 _Loth_ + 2 _Sicilici_ = 1 _Semuncia_ 16 _Loth_ = 1 _Mark_ + 16 _Semunciae_ = 1 _Bes_ + +The term "_nummus_," a coin, given above and in the text, appears in the +German translation as _pfennig_ as applied to both German scales, but as +they are of different values, we have left Agricola's adaptation in one +scale to avoid confusion. The Latin terms adopted by Agricola are given +below, together with the German:-- + + Number in one Value in + Roman Term. German Term. Mark or Bes. _Siliquae_. + + _Siliqua_ 1152 1 + + "Unit of 4 _Siliquae_" _Grenlin_ 288 4 + + _Pfennig_ 256 -- + + _Scripulum_ _Scruple_ (?) 192 6 + + _Semi-sextula_ _Gran_ 96 12 + + _Drachma_ _Quintlein_ 64 18 + + _Sextula_ _Halb Krat_ 48 24 + + _Sicilicus_ _Halb Loth_ 32 36 + + _Duella_ _Krat_ 24 48 + + _Semuncia_ _Loth_ 16 72 + + "_Unit of 5 Drachmae "_Nummus_" 12 96 + & 1 Scripulum_" + + _Uncia_ _Untzen_ 8 144 + + _Bes_ _Mark_ 1 1152 + +While the proportions in a _bes_ or _mark_ are the same in both scales, +the actual weight values are vastly different--for instance, the _mark_ +contained about 3609.6, and the _bes_ 3297 Troy Grains. Agricola also +uses: + + _Selibra_ _Halb-pfundt_ + _Libra_ _Pfundt_ + _Centumpondium_ _Centner_. + +As the Roman _libra_ contains 12 _unciae_ and the German _pfundt_ 16 +_untzen_, the actual weights of these latter quantities are still +further apart--the former 4946 and the latter 7219 Troy grains. + +[40] There are no tables in the Latin text, the whole having been +written out _in extenso_, but they have now been arranged as above, as +being in a much more convenient and expressive form. + +[41] See note 39 above. + +[42] See note 27, p. 242, for discussion of this "Assay ton" +arrangement. + +[43] _Agrippinenses_ and _Antuerpiani_. + + + + +BOOK VIII. + + +Questions of assaying were explained in the last Book, and I have now +come to a greater task, that is, to the description of how we extract +the metals. First of all I will explain the method of preparing the +ore[1]; for since Nature usually creates metals in an impure state, +mixed with earth, stones, and solidified juices, it is necessary to +separate most of these impurities from the ores as far as can be, before +they are smelted, and therefore I will now describe the methods by which +the ores are sorted, broken with hammers, burnt, crushed with stamps, +ground into powder, sifted, washed, roasted, and calcined[2]. + +I will start at the beginning with the first sort of work. Experienced +miners, when they dig the ore, sort the metalliferous material from +earth, stones, and solidified juices before it is taken from the shafts +and tunnels, and they put the valuable metal in trays and the waste into +buckets. But if some miner who is inexperienced in mining matters has +omitted to do this, or even if some experienced miner, compelled by some +unavoidable necessity, has been unable to do so, as soon as the material +which has been dug out has been removed from the mine, all of it should +be examined, and that part of the ore which is rich in metal sorted from +that part of it which is devoid of metal, whether such part be earth, or +solidified juices, or stones. To smelt waste together with an ore +involves a loss, for some expenditure is thrown away, seeing that out of +earth and stones only empty and useless slags are melted out, and +further, the solidified juices also impede the smelting of the metals +and cause loss. The rock which lies contiguous to rich ore should also +be broken into small pieces, crushed, and washed, lest any of the +mineral should be lost. When, either through ignorance or carelessness, +the miners while excavating have mixed the ore with earth or broken +rock, the work of sorting the crude metal or the best ore is done not +only by men, but also by boys and women. They throw the mixed material +upon a long table, beside which they sit for almost the whole day, and +they sort out the ore; when it has been sorted out, they collect it in +trays, and when collected they throw it into tubs, which are carried to +the works in which the ores are smelted. + +[Illustration 268 (Sorting Ore): A--Long table. B--Tray. C--Tub.] + +[Illustration 269 (Cutting Metal): A--Masses of metal. B--Hammer. +C--Chisel. D--Tree stumps. E--Iron tool similar to a pair of shears.] + +The metal which is dug out in a pure or crude state, to which class +belong native silver, silver glance, and gray silver, is placed on a +stone by the mine foreman and flattened out by pounding with heavy +square hammers. These masses, when they have been thus flattened out +like plates, are placed either on the stump of a tree, and cut into +pieces by pounding an iron chisel into them with a hammer, or else they +are cut with an iron tool similar to a pair of shears. One blade of +these shears is three feet long, and is firmly fixed in a stump, and the +other blade which cuts the metal is six feet long. These pieces of +metal are afterward heated in iron basins and smelted in the cupellation +furnace by the smelters. + +[Illustration 270 (Spalling Ore): A--Tables. B--Upright planks. +C--Hammer. D--Quadrangular hammer. E--Deeper vessel. F--Shallower +vessel. G--Iron rod.] + +Although the miners, in the shafts or tunnels, have sorted over the +material which they mine, still the ore which has been broken down and +carried out must be broken into pieces by a hammer or minutely crushed, +so that the more valuable and better parts can be distinguished from the +inferior and worthless portions. This is of the greatest importance in +smelting ore, for if the ore is smelted without this separation, the +valuable part frequently receives great damage before the worthless part +melts in the fire, or else the one consumes the other; this latter +difficulty can, however, be partly avoided by the exercise of care and +partly by the use of fluxes. Now, if a vein is of poor quality, the +better portions which have been broken down and carried out should be +thrown together in one place, and the inferior portion and the rock +thrown away. The sorters place a hard broad stone on a table; the tables +are generally four feet square and made of joined planks, and to the +edge of the sides and back are fixed upright planks, which rise about a +foot from the table; the front, where the sorter sits, is left open. The +lumps of ore, rich in gold or silver, are put by the sorters on the +stone and broken up with a broad, but not thick, hammer; they either +break them into pieces and throw them into one vessel, or they break and +sort--whence they get their name--the more precious from the worthless, +throwing and collecting them separately into different vessels. Other +men crush the lumps of ore less rich in gold or silver, which have +likewise been put on the stone, with a broad thick hammer, and when it +has been well crushed, they collect it and throw it into one vessel. +There are two kinds of vessels; one is deeper, and a little wider in the +centre than at the top or bottom; the other is not so deep though it is +broader at the bottom, and becomes gradually a little narrower toward +the top. The latter vessel is covered with a lid, while the former is +not covered; an iron rod through the handles, bent over on either end, +is grasped in the hand when the vessel is carried. But, above all, it +behooves the sorters to be assiduous in their labours. + +[Illustration 271 (Spalling Ore): A--Pyrites. B--Leggings. C--Gloves. +D--Hammer.] + +By another method of breaking ore with hammers, large hard fragments of +ore are broken before they are burned. The legs of the workmen--at all +events of those who crush pyrites in this manner with large hammers in +Goslar--are protected with coverings resembling leggings, and their +hands are protected with long gloves, to prevent them from being +injured by the chips which fly away from the fragments. + +[Illustration 272 (Spalling Ore): A--Area paved with stones. B--Broken +ore. C--Area covered with broken ore. D--Iron tool. E--Its handle. +F--Broom. G--Short strake. H--Wooden hoe.] + +In that district of Greater Germany which is called Westphalia and in +that district of Lower Germany which is named Eifel, the broken ore +which has been burned, is thrown by the workmen into a round area paved +with the hardest stones, and the fragments are pounded up with iron +tools, which are very much like hammers in shape and are used like +threshing sledges. This tool is a foot long, a palm wide, and a digit +thick, and has an opening in the middle just as hammers have, in which +is fixed a wooden handle of no great thickness, but up to three and a +half feet long, in order that the workmen can pound the ore with greater +force by reason of its weight falling from a greater height. They strike +and pound with the broad side of the tool, in the same way as corn is +pounded out on a threshing floor with the threshing sledges, although +the latter are made of wood and are smooth and fixed to poles. When the +ore has been broken into small pieces, they sweep it together with +brooms and remove it to the works, where it is washed in a short +strake, at the head of which stands the washer, who draws the water +upward with a wooden hoe. The water running down again, carries all the +light particles into a trough placed underneath. I shall deal more fully +with this method of washing a little later. + +Ore is burned for two reasons; either that from being hard, it may +become soft and more easily broken and more readily crushed with a +hammer or stamps, and then can be smelted; or that the fatty things, +that is to say, sulphur, bitumen, orpiment, or realgar[3] may be +consumed. Sulphur is frequently found in metallic ores, and, generally +speaking, is more harmful to the metals, except gold, than are the other +things. It is most harmful of all to iron, and less to tin than to +bismuth, lead, silver, or copper. Since very rarely gold is found in +which there is not some silver, even gold ores containing sulphur ought +to be roasted before they are smelted, because, in a very vigorous +furnace fire, sulphur resolves metal into ashes and makes slag of it. +Bitumen acts in the same way, in fact sometimes it consumes silver, +which we may see in bituminous _cadmia_[4]. + +[Illustration 274 (Stall Roasting Ore): A--Area. B--Wood. C--Ore. +D--Cone-shaped piles. E--Canal.] + +I now come to the methods of roasting, and first of all to that one +which is common to all ores. The earth is dug out to the required +extent, and thus is made a quadrangular area of fair size, open at the +front, and above this, firewood is laid close together, and on it other +wood is laid transversely, likewise close together, for which reason our +countrymen call this pile of wood a crate; this is repeated until the +pile attains a height of one or two cubits. Then there is placed upon it +a quantity of ore that has been broken into small pieces with a hammer; +first the largest of these pieces, next those of medium size, and lastly +the smallest, and thus is built up a gently sloping cone. To prevent it +from becoming scattered, fine sand of the same ore is soaked with water +and smeared over it and beaten on with shovels; some workers, if they +cannot obtain such fine sand, cover the pile with charcoal-dust, just as +do charcoal-burners. But at Goslar, the pile, when it has been built up +in the form of a cone, is smeared with _atramentum sutorium rubrum_[5], +which is made by the leaching of roasted pyrites soaked with water. In +some districts the ore is roasted once, in others twice, in others three +times, as its hardness may require. At Goslar, when pyrites is roasted +for the third time, that which is placed on the top of the pyre exudes a +certain greenish, dry, rough, thin substance, as I have elsewhere +written[6]; this is no more easily burned by the fire than is asbestos. +Very often also, water is put on to the ore which has been roasted, +while it is still hot, in order to make it softer and more easily +broken; for after fire has dried up the moisture in the ore, it breaks +up more easily while it is still hot, of which fact burnt limestone +affords the best example. + +[Illustration 275 (Heap Roasting Ore): A--Lighted pyre. B--Pyre which is +being constructed. C--Ore. D--Wood. E--Pile of the same wood.] + +By digging out the earth they make the areas much larger, and square; +walls should be built along the sides and back to hold the heat of the +fire more effectively, and the front should be left open. In these +compartments tin ore is roasted in the following manner. First of all +wood about twelve feet long should be laid in the area in four layers, +alternately straight and transverse. Then the larger pieces of ore +should be laid upon them, and on these again the smaller ones, which +should also be placed around the sides; the fine sand of the same ore +should also be spread over the pile and pounded with shovels, to prevent +the pile from falling before it has been roasted; the wood should then +be fired. + +[Illustration 276 (Stall Roasting Ore): A--Burning pyre which is +composed of lead ore with wood placed above it. B--Workman throwing ore +into another area. C--Oven-shaped furnace. D--Openings through which the +smoke escapes.] + +Lead ore, if roasting is necessary, should be piled in an area just like +the last, but sloping, and the wood should be placed over it. A tree +trunk should be laid right across the front of the ore to prevent it +from falling out. The ore, being roasted in this way, becomes partly +melted and resembles slag. Thuringian pyrites, in which there is gold, +sulphur, and vitriol, after the last particle of vitriol has been +obtained by heating it in water, is thrown into a furnace, in which logs +are placed. This furnace is very similar to an oven in shape, in order +that when the ore is roasted the valuable contents may not fly away with +the smoke, but may adhere to the roof of the furnace. In this way +sulphur very often hangs like icicles from the two openings of the roof +through which the smoke escapes. + +[Illustration 277 (Hearths for roasting): A--Iron plates full of holes. +B--Walls. C--Plate on which ore is placed. D--Burning charcoal placed on +the ore. E--Pots. F--Furnace. G--Middle part of upper chamber. H--The +other two compartments. I--Divisions of the lower chamber. K--Middle +wall. L--Pots which are filled with ore. M--Lids of same pots. +N--Grating.] + +If pyrites or _cadmia_, or any other ore containing metal, possesses a +good deal of sulphur or bitumen, it should be so roasted that neither is +lost. For this purpose it is thrown on an iron plate full of holes, and +roasted with charcoal placed on top; three walls support this plate, two +on the sides and the third at the back. Beneath the plate are placed +pots containing water, into which the sulphurous or bituminous vapour +descends, and in the water the fat accumulates and floats on the top. If +it is sulphur, it is generally of a yellow colour; if bitumen, it is +black like pitch. If these were not drawn out they would do much harm to +the metal, when the ore is being smelted. When they have thus been +separated they prove of some service to man, especially the sulphurous +kind. From the vapour which is carried down, not into the water, but +into the ground, there is created a sulphurous or a bituminous substance +resembling _pompholyx_[7], and so light that it can be blown away with a +breath. Some employ a vaulted furnace, open at the front and divided +into two chambers. A wall built in the middle of the furnace divides the +lower chamber into two equal parts, in which are set pots containing +water, as above described. The upper chamber is again divided into three +parts, the middle one of which is always open, for in it the wood is +placed, and it is not broader than the middle wall, of which it forms +the topmost portion. The other two compartments have iron doors which +are closed, and which, together with the roof, keep in the heat when the +wood is lighted. In these upper compartments are iron bars which take +the place of a floor, and on these are arranged pots without bottoms, +having in place of a bottom, a grating made of iron wire, fixed to each, +through the openings of which the sulphurous or bituminous vapours +roasted from the ore run into the lower pots. Each of the upper pots +holds a hundred pounds of ore; when they are filled they are covered +with lids and smeared with lute. + +[Illustration 278 (Heap Roasting): A--Heap of cupriferous stones. +B--Kindled heap. C--Stones being taken to the beds of faggots.] + +In Eisleben and the neighbourhood, when they roast the schistose stone +from which copper is smelted, and which is not free from bitumen, they +do not use piles of logs, but bundles of faggots. At one time, they used +to pile this kind of stone, when extracted from the pit, on bundles of +faggots and roast it by firing the faggots; nowadays, they first of all +carry these same stones to a heap, where they are left to lie for some +time in such a way as to allow the air and rain to soften them. Then +they make a bed of faggot bundles near the heap, and carry the nearest +stones to this bed; afterward they again place bundles of faggots in the +empty place from which the first stones have been removed, and pile over +this extended bed, the stones which lay nearest to the first lot; and +they do this right up to the end, until all the stones have been piled +mound-shape on a bed of faggots. Finally they fire the faggots, not, +however, on the side where the wind is blowing, but on the opposite +side, lest the fire blown up by the force of the wind should consume the +faggots before the stones are roasted and made soft; by this method the +stones which are adjacent to the faggots take fire and communicate it to +the next ones, and these again to the adjoining ones, and in this way +the heap very often burns continuously for thirty days or more. This +schist rock when rich in copper, as I have said elsewhere, exudes a +substance of a nature similar to asbestos. + +[Illustration 284 (Stamp-mill): A--Mortar. B--Upright posts. +C--Cross-beams. D--Stamps. E--Their heads. F--Axle (cam-shaft). G--Tooth +of the stamp (tappet). H--Teeth of axle (cams).] + +Ore is crushed with iron-shod stamps, in order that the metal may be +separated from the stone and the hangingwall rock.[8] The machines which +miners use for this purpose are of four kinds, and are made by the +following method. A block of oak timber six feet long, two feet and a +palm square, is laid on the ground. In the middle of this is fixed a +mortar-box, two feet and six digits long, one foot and six digits deep; +the front, which might be called a mouth, lies open; the bottom is +covered with a plate of iron, a palm thick and two palms and as many +digits wide, each end of which is wedged into the timber with broad +wedges, and the front and back part of it are fixed to the timber with +iron nails. To the sides of the mortar above the block are fixed two +upright posts, whose upper ends are somewhat cut back and are mortised +to the timbers of the building. Two and a half feet above the mortar +are placed two cross-beams joined together, one in front and one in the +back, the ends of which are mortised into the upright posts already +mentioned. Through each mortise is bored a hole, into which is driven an +iron clavis; one end of the clavis has two horns, and the other end is +perforated in order that a wedge driven through, binds the beams more +firmly; one horn of the clavis turns up and the other down. Three and a +half feet above the cross-beams, two other cross-beams of the same kind +are again joined in a similar manner; these cross-beams have square +openings, in which the iron-shod stamps are inserted. The stamps are not +far distant from each other, and fit closely in the cross-beams. Each +stamp has a tappet at the back, which requires to be daubed with grease +on the lower side that it can be raised more easily. For each stamp +there are on a cam-shaft, two cams, rounded on the outer end, which +alternately raise the stamp, in order that, by its dropping into the +mortar, it may with its iron head pound and crush the rock which has +been thrown under it. To the cam-shaft is fixed a water-wheel whose +buckets are turned by water-power. Instead of doors, the mouth of the +mortar has a board, which is fitted into notches cut out of the front of +the block. This board can be raised, in order that when the mouth is +open, the workmen can remove with a shovel the fine sand, and likewise +the coarse sand and broken rock, into which the rocks have been crushed; +this board can be lowered, so that the mouth thus being closed, the +fresh rock thrown in may be crushed with the iron-shod stamps. If an oak +block is not available, two timbers are placed on the ground and joined +together with iron clamps, each of the timbers being six feet long, a +foot wide, and a foot and a half thick. Such depth as should be allowed +to the mortar, is obtained by cutting out the first beam to a width of +three-quarters of a foot and to a length of two and a third and one +twenty-fourth of a foot. In the bottom of the part thus dug out, there +should be laid a very hard rock, a foot thick and three-quarters of a +foot wide; about it, if any space remains, earth or sand should be +filled in and pounded. On the front, this bed rock is covered with a +plank; this rock when it has been broken, should be taken away and +replaced by another. A smaller mortar having room for only three stamps +may also be made in the same manner. + +[Illustration 285 (Stamps): A--Stamp. B--Stem cut out in lower part. +C--Shoe. D--The other shoe, barbed and grooved. E--Quadrangular iron +band. F--Wedge. G--Tappet. H--Angular cam-shaft. I--Cams. K--Pair of +compasses.] + +The stamp-stems are made of small square timbers nine feet long and half +a foot wide each way. The iron head of each is made in the following +way; the lower part of the head is three palms long and the upper part +the same length. The lower part is a palm square in the middle for two +palms, then below this, for a length of two digits it gradually spreads +until it becomes five digits square; above the middle part, for a length +of two digits, it again gradually swells out until it becomes a palm and +a half square. Higher up, where the head of the shoe is enclosed in the +stem, it is bored through and similarly the stem itself is pierced, and +through the opening of each, there passes a broad iron wedge, which +prevents the head falling off the stem. To prevent the stamp head from +becoming broken by the constant striking of fragments of ore or rocks, +there is placed around it a quadrangular iron band a digit thick, seven +digits wide, and six digits deep. Those who use three stamps, as is +common, make them much larger, and they are made square and three palms +broad each way; then the iron shoe of each has a total length of two +feet and a palm; at the lower end, it is hexagonal, and at that point it +is seven digits wide and thick. The lower part of it which projects +beyond the stem is one foot and two palms long; the upper part, which is +enclosed in the stem, is three palms long; the lower part is a palm +wide and thick; then gradually the upper part becomes narrower and +thinner, so that at the top it is three digits and a half wide and two +thick. It is bored through at the place where the angles have been +somewhat cut away; the hole is three digits long and one wide, and is +one digit's distance from the top. There are some who make that part of +the head which is enclosed in the stem, barbed and grooved, in order +that when the hooks have been fixed into the stem and wedges fitted to +the grooves, it may remain tightly fixed, especially when it is also +held with two quadrangular iron bands. Some divide the cam-shaft with a +compass into six sides, others into nine; it is better for it to be +divided into twelve sides, in order that successively one side may +contain a cam and the next be without one. + +[Illustration 286 (Stamp-mill): A--Box. Although the upper part is not +open, it is shown open here, that the wheel may be seen. B--Wheel. +C--Cam-shaft. D--Stamps.] + +The water-wheel is entirely enclosed under a quadrangular box, in case +either the deep snows or ice in winter, or storms, may impede its +running and its turning around. The joints in the planks are stopped all +around with moss. The cover, however, has one opening, through which +there passes a race bringing down water which, dropping on the buckets +of the wheel, turns it round, and flows out again in the lower race +under the box. The spokes of the water-wheel are not infrequently +mortised into the middle of the cam-shaft; in this case the cams on +both sides raise the stamps, which either both crush dry or wet ore, or +else the one set crushes dry ore and the other set wet ore, just as +circumstances require the one or the other; further, when the one set is +raised and the iron clavises in them are fixed into openings in the +first cross-beam, the other set alone crushes the ore. + +[Illustration 287 (Handling stamped material): A--Box laid flat on the +ground. B--Its bottom which is made of iron wire. C--Box inverted. +D--Iron rods. E--Box suspended from a beam, the inside being visible. +F--Box suspended from a beam, the outside being visible.] + +Broken rock or stones, or the coarse or fine sand, are removed from the +mortar of this machine and heaped up, as is also done with the same +materials when raked out of the dump near the mine. They are thrown by a +workman into a box, which is open on the top and the front, and is three +feet long and nearly a foot and a half wide. Its sides are sloping and +made of planks, but its bottom is made of iron wire netting, and +fastened with wire to two iron rods, which are fixed to the two side +planks. This bottom has openings, through which broken rock of the size +of a hazel nut cannot pass; the pieces which are too large to pass +through are removed by the workman, who again places them under stamps, +while those which have passed through, together with the coarse and fine +sand, he collects in a large vessel and keeps for the washing. When he +is performing his laborious task he suspends the box from a beam by two +ropes. This box may rightly be called a quadrangular sieve, as may also +that kind which follows. + +[Illustration 288 (Sifting Ore): A--Sieve. B--Small planks. C--Post. +D--Bottom of sieve. E--Open box. F--Small cross-beam. G--Upright posts.] + +Some employ a sieve shaped like a wooden bucket, bound with two iron +hoops; its bottom, like that of the box, is made of iron wire netting. +They place this on two small cross-planks fixed upon a post set in the +ground. Some do not fix the post in the ground, but stand it on the +ground until there arises a heap of the material which has passed +through the sieve, and in this the post is fixed. With an iron shovel +the workman throws into this sieve broken rock, small stones, coarse and +fine sand raked out of the dump; holding the handles of the sieve in his +hands, he agitates it up and down in order that by this movement the +dust, fine and coarse sand, small stones, and fine broken rock may fall +through the bottom. Others do not use a sieve, but an open box, whose +bottom is likewise covered with wire netting; this they fix on a small +cross-beam fastened to two upright beams and tilt it backward and +forward. + +[Illustration 289 (Sifting Ore): A--Box. B--Bale. C--Rope. D--Beam. +E--Handles. F--Five-toothed rake. G--Sieve. H--Its handles. I--Pole. +K--Rope. L--Timber.] + +Some use a sieve made of copper, having square copper handles on both +sides, and through these handles runs a pole, of which one end projects +three-quarters of a foot beyond one handle; the workman then places that +end in a rope which is suspended from a beam, and rapidly shakes the +pole alternately backward and forward. By this movement the small +particles fall through the bottom of the sieve. In order that the end of +the pole may be easily placed in the rope, a stick, two palms long, +holds open the lower part of the rope as it hangs double, each end of +the rope being tied to the beam; part of the rope, however, hangs beyond +the stick to a length of half a foot. A large box is also used for this +purpose, of which the bottom is either made of a plank full of holes or +of iron netting, as are the other boxes. An iron bale is fastened from +the middle of the planks which form its sides; to this bale is fastened +a rope which is suspended from a wooden beam, in order that the box may +be moved or tilted in any direction. There are two handles on each end, +not unlike the handles of a wheelbarrow; these are held by two workmen, +who shake the box to and fro. This box is the one principally used by +the Germans who dwell in the Carpathian mountains. The smaller particles +are separated from the larger ones by means of three boxes and two +sieves, in order that those which pass through each, being of equal +size, may be washed together; for the bottoms of both the boxes and +sieves have openings which do not let through broken rock of the size of +a hazel nut. As for the dry remnants in the bottoms of the sieves, if +they contain any metal the miners put them under the stamps. The larger +pieces of broken rock are not separated from the smaller by this method +until the men and boys, with five-toothed rakes, have separated them +from the rock fragments, the little stones, the coarse and the fine sand +and earth, which have been thrown on to the dumps. + +[Illustration 291 (Sifting Ore): A--Workman carrying broken rock in a +barrow. B--First chute. C--First box. D--Its handles. E--Its bales. +F--Rope. G--Beam. H--Post. I--Second chute. K--Second box. L--Third +chute. M--Third box. N--First table. O--First sieve. P--First tub. +Q--Second table. R--Second sieve. S--Second tub. T--Third table. +V--Third sieve. X--Third tub. Y--Plugs.] + +At Neusohl, in the Carpathians, there are mines where the veins of +copper lie in the ridges and peaks of the mountains, and in order to +save expense being incurred by a long and difficult transport, along a +rough and sometimes very precipitous road, one workman sorts over the +dumps which have been thrown out from the mines, and another carries in +a wheelbarrow the earth, fine and coarse sand, little stones, broken +rock, and even the poorer ore, and overturns the barrow into a long open +chute fixed to a steep rock. This chute is held apart by small cleats, +and the material slides down a distance of about one hundred and fifty +feet into a short box, whose bottom is made of a thick copper plate, +full of holes. This box has two handles by which it is shaken to and +fro, and at the top there are two bales made of hazel sticks, in which +is fixed the iron hook of a rope hung from the branch of a tree or from +a wooden beam which projects from an upright post. From time to time a +sifter pulls this box and thrusts it violently against the tree or post, +by which means the small particles passing through its holes descend +down another chute into another short box, in whose bottom there are +smaller holes. A second sifter, in like manner, thrusts this box +violently against a tree or post, and a second time the smaller +particles are received into a third chute, and slide down into a third +box, whose bottom has still smaller holes. A third sifter, in like +manner, thrusts this box violently against a tree or post, and for the +third time the tiny particles fall through the holes upon a table. While +the workman is bringing in the barrow, another load which has been +sorted from the dump, each sifter withdraws the hooks from his bale and +carries away his own box and overturns it, heaping up the broken rock or +sand which remains in the bottom of it. As for the tiny particles which +have slid down upon the table, the first washer--for there are as many +washers as sifters--sweeps them off and in a tub nearly full of water, +washes them through a sieve whose holes are smaller than the holes of +the third box. When this tub has been filled with the material which has +passed through the sieve, he draws out the plug to let the water run +away; then he removes with a shovel that which has settled in the tub +and throws it upon the table of a second washer, who washes it in a +sieve with smaller holes. The sediment which has this time settled in +his tub, he takes out and throws on the table of a third washer, who +washes it in a sieve with the smallest holes. The copper concentrates +which have settled in the last tub are taken out and smelted; the +sediment which each washer has removed with a limp is washed on a canvas +strake. The sifters at Altenberg, in the tin mines of the mountains +bordering on Bohemia, use such boxes as I have described, hung from +wooden beams. These, however, are a little larger and open in the front, +through which opening the broken rock which has not gone through the +sieve can be shaken out immediately by thrusting the sieve against its +post. + +[Illustration 292 (Sifting Ore): A--Sieve. B--Its handles. C--Tub. +D--Bottom of sieve made of iron wires. E--Hoop. F--Rods. G--Hoops. +H--Woman shaking the sieve. I--Boy supplying it with material which +requires washing. K--Man with shovel removing from the tub the material +which has passed through the sieve.] + +If the ore is rich in metal, the earth, the fine and coarse sand, and +the pieces of rock which have been broken from the hangingwall, are dug +out of the dump with a spade or rake and, with a shovel, are thrown into +a large sieve or basket, and washed in a tub nearly full of water. The +sieve is generally a cubit broad and half a foot deep; its bottom has +holes of such size that the larger pieces of broken rock cannot pass +through them, for this material rests upon the straight and cross iron +wires, which at their points of contact are bound by small iron clips. +The sieve is held together by an iron band and by two cross-rods +likewise of iron; the rest of the sieve is made of staves in the shape +of a little tub, and is bound with two iron hoops; some, however, bind +it with hoops of hazel or oak, but in that case they use three of them. +On each side it has handles, which are held in the hands by whoever +washes the metalliferous material. Into this sieve a boy throws the +material to be washed, and a woman shakes it up and down, turning it +alternately to the right and to the left, and in this way passes +through it the smaller pieces of earth, sand, and broken rock. The +larger pieces remain in the sieve, and these are taken out, placed in a +heap and put under the stamps. The mud, together with fine sand, coarse +sand, and broken rock, which remain after the water has been drawn out +of the tub, is removed by an iron shovel and washed in the sluice, about +which I will speak a little later. + +[Illustration 293 (Sifting Ore): A--Basket. B--Its handles. C--Dish. +D--Its back part. E--Its front part. F--Handles of same.] + +The Bohemians use a basket a foot and a half broad and half a foot deep, +bound together by osiers. It has two handles by which it is grasped, +when they move it about and shake it in the tub or in a small pool +nearly full of water. All that passes through it into the tub or pool +they take out and wash in a bowl, which is higher in the back part and +lower and flat in the front; it is grasped by the two handles and shaken +in the water, the lighter particles flowing away, and the heavier and +mineral portion sinking to the bottom. + +[Illustration 294 (Mills for Grinding Ore): A--Axle. B--Water-wheel. +C--Toothed drum. D--Drum made of rundles. E--Iron axle. F--Millstone. +G--Hopper. H--Round wooden plate. I--Trough.] + +Gold ore, after being broken with hammers or crushed by the stamps, and +even tin ore, is further milled to powder. The upper millstone, which +is turned by water-power, is made in the following way. An axle is +rounded to compass measure, or is made angular, and its iron pinions +turn in iron sockets which are held in beams. The axle is turned by a +water-wheel, the buckets of which are fixed to the rim and are struck by +the force of a stream. Into the axle is mortised a toothed drum, whose +teeth are fixed in the side of the rim. These teeth turn a second drum +of rundles, which are made of very hard material. This drum surrounds an +iron axle which has a pinion at the bottom and revolves in an iron cup +in a timber. At the top of the iron axle is an iron tongue, dove-tailed +into the millstone, and so when the teeth of the one drum turn the +rundles of the other, the millstone is made to turn round. An +overhanging machine supplies it with ore through a hopper, and the ore, +being ground to powder, is discharged from a round wooden plate into a +trough and flowing away through it accumulates on the floor; from there +the ore is carried away and reserved for washing. Since this method of +grinding requires the millstone to be now raised and now lowered, the +timber in whose socket the iron of the pinion axle revolves, rests upon +two beams, which can be raised and lowered. + +[Illustration 296 (Mills for Grinding Ore): A--First mill. B--Wheel +turned by goats. C--Second mill. D--Disc of upright axle. E--Its toothed +drum. F--Third mill. G--Shape of lower millstone. H--Small upright axle +of the same. I--Its opening. K--Lever of the upper millstone. L--Its +opening.] + +There are three mills in use in milling gold ores, especially for +quartz[11] which is not lacking in metal. They are not all turned by +water-power, but some by the strength of men, and two of them even by +the power of beasts of burden. The first revolving one differs from the +next only in its driving wheel, which is closed in and turned by men +treading it, or by horses, which are placed inside, or by asses, or even +by strong goats; the eyes of these beasts are covered by linen bands. +The second mill, both when pushed and turned round, differs from the two +above by having an upright axle in the place of the horizontal one; this +axle has at its lower end a disc, which two workmen turn by treading +back its cleats with their feet, though frequently one man sustains all +the labour; or sometimes there projects from the axle a pole which is +turned by a horse or an ass, for which reason it is called an +_asinaria_. The toothed drum which is at the upper end of the axle turns +the drum which is made of rundles, and together with it the millstone. + +The third mill is turned round and round, and not pushed by hand; but +between this and the others there is a great distinction, for the lower +millstone is so shaped at the top that it can hold within it the upper +millstone, which revolves around an iron axle; this axle is fastened in +the centre of the lower stone and passes through the upper stone. A +workman, by grasping in his hand an upright iron bar placed in the upper +millstone, moves it round. The middle of the upper millstone is bored +through, and the ore, being thrown into this opening, falls down upon +the lower millstone and is there ground to powder, which gradually runs +out through its opening; it is washed by various methods before it is +mixed with quicksilver, which I will explain presently. + +[Illustration 299 (Stamp-mill): A--Water-wheel. B--Axle. C--Stamp. +D--Hopper in the upper millstone. E--Opening passing through the centre. +F--Lower millstone. G--Its round depression. H--Its outlet. I--Iron +axle. K--Its crosspiece. L--Beam. M--Drum of rundles on the iron axle. +N--Toothed drum of main axle. O--Tubs. P--The small planks. Q--Small +upright axles. R--Enlarged part of one. S--Their paddles. T--Their drums +which are made of rundles. V--Small horizontal axle set into the end of +the main axle. X--Its toothed drums. Y--Three sluices. Z--Their small +axles. AA--Spokes. BB--Paddles.] + +Some people build a machine which at one and the same time can crush, +grind, cleanse, and wash the gold ore, and mix the gold with +quicksilver. This machine has one water-wheel, which is turned by a +stream striking its buckets; the main axle on one side of the +water-wheel has long cams, which raise the stamps that crush the dry +ore. Then the crushed ore is thrown into the hopper of the upper +millstone, and gradually falling through the opening, is ground to +powder. The lower millstone is square, but has a round depression in +which the round, upper millstone turns, and it has an outlet from which +the powder falls into the first tub. A vertical iron axle is dove-tailed +into a cross-piece, which is in turn fixed into the upper millstone; the +upper pinion of this axle is held in a bearing fixed in a beam; the drum +of the vertical axle is made of rundles, and is turned by the toothed +drum on the main axle, and thus turns the millstone. The powder falls +continually into the first tub, together with water, and from there runs +into a second tub which is set lower down, and out of the second into a +third, which is the lowest; from the third, it generally flows into a +small trough hewn out of a tree trunk. Quicksilver[12] is placed in +each tub, across which is fixed a small plank, and through a hole in the +middle of each plank there passes a small upright axle, which is +enlarged above the plank to prevent it from dropping into the tub lower +than it should. At the lower end of the axle three sets of paddles +intersect, each made from two little boards fixed to the axle opposite +each other. The upper end of this axle has a pinion held by a bearing +set in a beam, and around each of these axles is a small drum made of +rundles, each of which is turned by a small toothed drum on a horizontal +axle, one end of which is mortised into the large horizontal axle, and +the other end is held in a hollow covered with thick iron plates in a +beam. Thus the paddles, of which there are three sets in each tub, turn +round, and agitating the powder, thoroughly mix it with water and +separate the minute particles of gold from it, and these are attracted +by the quicksilver and purified. The water carries away the waste. The +quicksilver is poured into a bag made of leather or cloth woven from +cotton, and when this bag is squeezed, as I have described elsewhere, +the quicksilver drips through it into a jar placed underneath. The pure +gold[13] remains in the bag. Some people substitute three broad sluices +for the tubs, each of which has an angular axle on which are set six +narrow spokes, and to them are fixed the same number of broad paddles; +the water that is poured in strikes these paddles and turns them round, +and they agitate the powder which is mixed with the water and separate +the metal from it. If the powder which is being treated contains gold +particles, the first method of washing is far superior, because the +quicksilver in the tubs immediately attracts the gold; if it is powder +in which are the small black stones from which tin is smelted, this +latter method is not to be despised. It is very advantageous to place +interlaced fir boughs in the sluices in which such tin-stuff is washed, +after it has run through the launders from the mills, because the fine +tin-stone is either held back by the twigs, or if the current carries +them along they fall away from the water and settle down. + +Seven methods of washing are in common use for the ores of many metals; +for they are washed either in a simple buddle, or in a divided buddle, +or in an ordinary strake, or in a large tank, or in a short strake, or +in a canvas strake, or in a jigging sieve. Other methods of washing are +either peculiar to some particular metal, or are combined with the +method of crushing wet ore by stamps. + +[Illustration 301 (Buddles): A--Head of buddle. B--Pipe. C--Buddle. +D--Board. E--Transverse buddle. F--Shovel. G--Scrubber.] + +A simple buddle is made in the following way. In the first place, the +head is higher than the rest of the buddle, and is three feet long and a +foot and a half broad; this head is made of planks laid upon a timber +and fastened, and on both sides, side-boards are set up so as to hold +the water, which flows in through a pipe or trough, so that it shall +fall straight down. The middle of the head is somewhat depressed in +order that the broken rock and the larger metallic particles may settle +into it. The buddle is sunk into the earth to a depth of three-quarters +of a foot below the head, and is twelve feet long and a foot and a half +wide and deep; the bottom and each side are lined with planks to prevent +the earth, when it is softened by the water, from falling in or from +absorbing the metallic particles. The lower end of the buddle is +obstructed by a board, which is not as high as the sides. To this +straight buddle there is joined a second transverse buddle, six feet +long and a foot and a half wide and deep, similarly lined with planks; +at the lower end it is closed up with a board, also lower than the +sides of the buddle so that the water can flow away; this water falls +into a launder and is carried outside the building. In this simple +buddle is washed the metallic material which has passed on to the floor +of the works through the five large sieves. When this has been gathered +into a heap, the washer throws it into the head of the buddle, and water +is poured upon it through the pipe or small trough, and the portion +which sinks and settles in the middle of the head compartment he stirs +with a wooden scrubber,--this is what we will henceforth call the +implement made of a stick to which is fixed a piece of wood a foot long +and a palm broad. The water is made turbid by this stirring, and carries +the mud and sand and small particles of metal into the buddle below. +Together with the broken rock, the larger metallic particles remain in +the head compartment, and when these have been removed, boys throw them +upon the platform of a washing tank or the short strake, and separate +them from the broken rock. When the buddle is full of mud and sand, the +washer closes the pipe through which the water flows into the head; very +soon the water which remains in the buddle flows away, and when this has +taken place, he removes with a shovel the mud and sand which are mixed +with minute particles of metal, and washes them on a canvas strake. +Sometimes before the buddles have been filled full, the boys throw the +material into a bowl and carry it to the strakes and wash it. + +Pulverized ore is washed in the head of this kind of a buddle; but +usually when tin-stone is washed in it, interlacing fir boughs are put +into the buddle, in the same manner as in the sluice when wet ore is +crushed with stamps. The larger tin-stone particles, which sink in the +upper part of the buddle, are washed separately in a strake; those +particles which are of medium size, and settle in the middle part, are +washed separately in the same way; and the mud mixed with minute +particles of tin-stone, which has settled in the lowest part of the +buddle below the fir boughs, is washed separately on the canvas strakes. + +[Illustration 302 (Buddles): A--Pipe. B--Cross launder. C--Small +troughs. D--Head of the buddle. E--Wooden scrubber. F--Dividing boards. +G--Short strake.] + +The divided buddle differs from the last one by having several +cross-boards, which, being placed inside it, divide it off like steps; +if the buddle is twelve feet long, four of them are placed within; if +nine feet long, three. The nearer each one is to the head, the greater +is its height; the further from the head, the lower it is; and so when +the highest is a foot and a palm high, the second is usually a foot and +three digits high, the third a foot and two digits, and the lowest a +foot and one digit. In this buddle is generally washed that +metalliferous material which has been sifted through the large sieve +into the tub containing water. This material is continuously thrown with +an iron shovel into the head of the buddle, and the water which has been +let in is stirred up by a wooden scrubber, until the buddle is full, +then the cross-boards are taken out by the washer, and the water is +drained off; next the metalliferous material which has settled in the +compartments is again washed, either on a short strake or on the canvas +strakes or in the jigging sieves. Since a short strake is often united +with the upper part of this buddle, a pipe in the first place carries +the water into a cross launder, from which it flows down through one +little launder into the buddle, and through another into the short +strake. + +[Illustration 303 (Washing material): A--Head. B--Strake. C--Trowel. +D--Scrubber. E--Canvas. F--Rod by which the canvas is made smooth.] + +An ordinary strake, so far as the planks are concerned, is not unlike +the last two. The head of this, as of the others, is first made of earth +stamped down, then covered with planks; and where it is necessary, earth +is thrown in and beaten down a second time, so that no crevice may +remain through which water carrying the particles of metal can escape. +The water ought to fall straight down into the strake, which has a +length of eight feet and a breadth of a foot and a half; it is +connected with a transverse launder, which then extends to a settling +pit outside the building. A boy with a shovel or a ladle takes the +impure concentrates or impure tin-stone from a heap, and throws them +into the head of the strake or spreads them over it. A washer with a +wooden scrubber then agitates them in the strake, whereby the mud mixed +with water flows away into the transverse launder, and the concentrates +or the tin-stone settle on the strake. Since sometimes the concentrates +or fine tin-stone flow down together with the mud into the transverse +launder, a second washer closes it, after a distance of about six feet, +with a cross-board and frequently stirs the mud with a shovel, in order +that when mixed with water it may flow out into the settling-pit; and +there remains in the launder only the concentrates or tin-stone. The +tin-stuff of Schlackenwald and Erbisdorff is washed in this kind of a +strake once or twice; those of Altenberg three or four times; those of +Geyer often seven times; for in the ore at Schlackenwald and Erbisdorff +the tin-stone particles are of a fair size, and are crushed with stamps; +at Altenberg they are of much smaller size, and in the broken ore at +Geyer only a few particles of tin-stone can be seen occasionally. + +This method of washing was first devised by the miners who treated tin +ore, whence it passed on from the works of the tin workers to those of +the silver workers and others; this system is even more reliable than +washing in jigging-sieves. Near this ordinary strake there is generally +a canvas strake. + +[Illustration 305 (Washing material): A--Upper cross launder. B--Small +launders. C--Heads of strakes. D--Strakes. E--Lower transverse launder. +F--Settling pit. G--Socket in the sill. H--Halved iron rings fixed to +beam. I--Pole. K--Its little scrubber. L--Second small scrubber.] + +In modern times two ordinary strakes, similarly made, are generally +joined together; the head of one is three feet distant from that of the +other, while the bodies are four feet distant from each other, and there +is only one cross launder under the two strakes. One boy shovels, from +the heap into the head of each, the concentrates or tin-stone mixed with +mud. There are two washers, one of whom sits at the right side of one +strake, and the other at the left of the other strake, and each pursues +his task, using the following sort of implement. Under each strake is a +sill, from a socket in which a round pole rises, and is held by half an +iron ring in a beam of the building, so that it may revolve; this pole +is nine feet long and a palm thick. Penetrating the pole is a small +round piece of wood, three palms long and as many digits thick, to which +is affixed a small board two feet long and five digits wide, in an +opening of which one end of a small axle revolves, and to this axle is +fixed the handle of a little scrubber. The other end of this axle turns +in an opening of a second board, which is likewise fixed to a small +round piece of wood; this round piece, like the first one, is three +palms long and as many digits thick, and is used by the washer as a +handle. The little scrubber is made of a stick three feet long, to the +end of which is fixed a small tablet of wood a foot long, six digits +broad, and a digit and a half thick. The washer constantly moves the +handle of this implement with one hand; in this way the little scrubber +stirs the concentrates or the fine tin-stone mixed with mud in the head +of the strake, and the mud, on being stirred, flows on to the strake. In +the other hand he holds a second little scrubber, which has a handle +of half the length, and with this he ceaselessly stirs the concentrates +or tin-stone which have settled in the upper part of the strake; in this +way the mud and water flow down into the transverse launder, and from it +into the settling-pit which is outside the building. + +[Illustration 306 (Washing material): A--Trough. B--Platform. C--Wooden +scrubber.] + +Before the short strake and the jigging-sieve had been invented, +metalliferous ores, especially tin, were crushed dry with stamps and +washed in a large trough hollowed out of one or two tree trunks; and at +the head of this trough was a platform, on which the ore was thrown +after being completely crushed. The washer pulled it down into the +trough with a wooden scrubber which had a long handle, and when the +water had been let into the trough, he stirred the ore with the same +scrubber. + +[Illustration 307 (Washing material): A--Short strake. B--Small launder. +C--Transverse launder. D--Wooden scrubber.] + +The short strake is narrow in the upper part where the water flows down +into it through the little launder; in fact it is only two feet wide; at +the lower end it is wider, being three feet and as many palms. At the +sides, which are six feet long, are fixed boards two palms high. In +other respects the head resembles the head of the simple buddle, except +that it is not depressed in the middle. Beneath is a cross launder +closed by a low board. In this short strake not only is ore agitated and +washed with a wooden scrubber, but boys also separate the concentrates +from the broken rock in them and collect them in tubs. The short strake +is now rarely employed by miners, owing to the carelessness of the boys, +which has been frequently detected; for this reason, the jigging-sieve +has taken its place. The mud which settles in the launder, if the ore is +rich, is taken up and washed in a jigging-sieve or on a canvas strake. + +[Illustration 308 (Washing material): A--Beams. B--Canvas. C--Head of +strake. D--Small launder. E--Settling pit or tank. F--Wooden scrubber. +G--Tubs.] + +A canvas strake is made in the following way. Two beams, eighteen feet +long and half a foot broad and three palms thick, are placed on a slope; +one half of each of these beams is partially cut away lengthwise, to +allow the ends of planks to be fastened in them, for the bottom is +covered by planks three feet long, set crosswise and laid close +together. One half of each supporting beam is left intact and rises a +palm above the planks, in order that the water that is running down may +not escape at the sides, but shall flow straight down. The head of the +strake is higher than the rest of the body, and slopes so as to enable +the water to flow away. The whole strake is covered by six stretched +pieces of canvas, smoothed with a stick. The first of them occupies the +lowest division, and the second is so laid as to slightly overlap it; on +the second division, the third is similarly laid, and so on, one on the +other. If they are laid in the opposite way, the water flowing down +carries the concentrates or particles of tin-stone under the canvas, and +a useless task is attempted. Boys or men throw the concentrates or +tin-stuff mixed with mud into the head of the strake, after the canvas +has been thus stretched, and having opened the small launder they let +the water flow in; then they stir the concentrates or tin-stone with a +wooden scrubber till the water carries them all on to the canvas; next +they gently sweep the linen with the wooden scrubber until the mud flows +into the settling-pit or into the transverse launder. As soon as there +is little or no mud on the canvas, but only concentrates or tin-stone, +they carry the canvas away and wash it in a tub placed close by. The +tin-stone settles in the tub, and the men return immediately to the same +task. Finally, they pour the water out of the tub, and collect the +concentrates or tin-stone. However, if either concentrates or tin-stone +have washed down from the canvas and settled in the settling-pit or in +the transverse launder, they wash the mud again. + +[Illustration 309 (Collecting concentrates): A--Canvas strake. B--Man +dashing water on the canvas. C--Bucket. D--Bucket of another kind. +E--Man removing concentrates or tin-stone from the trough.] + +Some neither remove the canvas nor wash it in the tubs, but place over +it on each edge narrow strips, of no great thickness, and fix them to +the beams with nails. They agitate the metalliferous material with +wooden scrubbers and wash it in a similar way. As soon as little or no +mud remains on the canvas, but only concentrates or fine tin-stone, they +lift one beam so that the whole strake rests on the other, and dash it +with water, which has been drawn with buckets out of the small tank, and +in this way all the sediment which clings to the canvas falls into the +trough placed underneath. This trough is hewn out of a tree and placed +in a ditch dug in the ground; the interior of the trough is a foot wide +at the top, but narrower in the bottom, because it is rounded out. In +the middle of this trough they put a cross-board, in order that the +fairly large particles of concentrates or fairly large-sized tin-stone +may remain in the forepart into which they have fallen, and the fine +concentrates or fine tin-stone in the lower part, for the water flows +from one into the other, and at last flows down through an opening into +the pit. As for the fairly large-sized concentrates or tin-stone which +have been removed from the trough, they are washed again on the ordinary +strake. The fine concentrates and fine tin-stone are washed again on +this canvas strake. By this method, the canvas lasts longer because it +remains fixed, and nearly double the work is done by one washer as +quickly as can be done by two washers by the other method. + +[Illustration 311 (Jigging Sieve): A--Fine sieves. B--Limp. C--Finer +sieve. D--Finest sieve.] + +The jigging sieve has recently come into use by miners. The +metalliferous material is thrown into it and sifted in a tub nearly full +of water. The sieve is shaken up and down, and by this movement all the +material below the size of a pea passes through into the tub, and the +rest remains on the bottom of the sieve. This residue is of two kinds, +the metallic particles, which occupy the lower place, and the particles +of rock and earth, which take the higher place, because the heavy +substance always settles, and the light is borne upward by the force of +the water. This light material is taken away with a limp, which is a +thin tablet of wood almost semicircular in shape, three-quarters of a +foot long, and half a foot wide. Before the lighter portion is taken +away the contents of the sieve are generally divided crosswise with a +limp, to enable the water to penetrate into it more quickly. Afterward +fresh material is again thrown into the sieve and shaken up and down, +and when a great quantity of metallic particles have settled in the +sieve, they are taken out and put into a tray close by. But since there +fall into the tub with the mud, not only particles of gold or silver, +but also of sand, pyrites, _cadmia_, galena, quartz, and other +substances, and since the water cannot separate these from the metallic +particles because they are all heavy, this muddy mixture is washed a +second time, and the part which is useless is thrown away. To prevent +the sieve passing this sand again too quickly, the washer lays small +stones or gravel in the bottom of the sieve. However, if the sieve is +not shaken straight up and down, but is tilted to one side, the small +stones or broken ore move from one part to another, and the metallic +material again falls into the tub, and the operation is frustrated. The +miners of our country have made an even finer sieve, which does not fail +even with unskilled washers; in washing with this sieve they have no +need for the bottom to be strewn with small stones. By this method the +mud settles in the tub with the very fine metallic particles, and the +larger sizes of metal remain in the sieve and are covered with the +valueless sand, and this is taken away with a limp. The concentrates +which have been collected are smelted together with other things. The +mud mixed with the very fine metallic particles is washed for a third +time and in the finest sieve, whose bottom is woven of hair. If the ore +is rich in metal, all the material which has been removed by the limp is +washed on the canvas strakes, or if the ore is poor it is thrown away. + +I have explained the methods of washing which are used in common for the +ores of many metals. I now come to another method of crushing ore, for I +ought to speak of this before describing those methods of washing which +are peculiar to ores of particular metals. + +[Illustration 313 (Stamp-mill): A--Mortar. B--Open end of mortar. +C--Slab of rock. D--Iron sole plates. E--Screen. F--Launder. G--Wooden +shovel. H--Settling pit. I--Iron shovel. K--Heap of material which has +settled. L--Ore which requires crushing. M--Small launder.] + +In the year 1512, George, the illustrious Duke of Saxony[14], gave the +overlordship of all the dumps ejected from the mines in Meissen to the +noble and wise Sigismund Maltitz, father of John, Bishop of Meissen. +Rejecting the dry stamps, the large sieve, and the stone mills of +Dippoldswalde and Altenberg, in which places are dug the small black +stones from which tin is smelted, he invented a machine which could +crush the ore wet under iron-shod stamps. That is called "wet ore" which +is softened by water which flows into the mortar box, and they are +sometimes called "wet stamps" because they are drenched by the same +water; and on the other hand, the other kinds are called "dry stamps" or +"dry ore," because no water is used to soften the ore when the stamps +are crushing. But to return to our subject. This machine is not +dissimilar to the one which crushes the ore with dry iron-shod stamps, +but the heads of the wet stamps are larger by half than the heads of the +others. The mortar-box, which is made of oak or beech timber, is set up +in the space between the upright posts; it does not open in front, but +at one end, and it is three feet long, three-quarters of a foot wide, +and one foot and six digits deep. If it has no bottom, it is set up in +the same way over a slab of hard, smooth rock placed in the ground, +which has been dug down a little. The joints are stopped up all round +with moss or cloth rags. If the mortar has a bottom, then an iron +sole-plate, three feet long, three-quarters of a foot wide, and a palm +thick, is placed in it. In the opening in the end of the mortar there is +fixed an iron plate full of holes, in such a way that there is a space +of two digits between it and the shoe of the nearest stamp, and the same +distance between this screen and the upright post, in an opening through +which runs a small but fairly long launder. The crushed particles of +silver ore flow through this launder with the water into a settling-pit, +while the material which settles in the launder is removed with an iron +shovel to the nearest planked floor; that material which has settled in +the pit is removed with an iron shovel on to another floor. Most people +make two launders, in order that while the workman empties one of them +of the accumulation which has settled in it, a fresh deposit may be +settling in the other. The water flows in through a small launder at the +other end of the mortar that is near the water-wheel which turns the +machine. The workman throws the ore to be crushed into the mortar in +such a way that the pieces, when they are thrown in among the stamps, do +not impede the work. By this method a silver or gold ore is crushed very +fine by the stamps. + +[Illustration 314 (Buddle): A--Launder reaching to the screen. +B--Transverse trough. C--Spouts. D--Large buddles. E--Shovel. +F--Interwoven twigs. G--Boards closing the buddles. H--Cross trough.] + +When tin ore is crushed by this kind of iron-shod stamps, as soon as +crushing begins, the launder which extends from the screen discharges +the water carrying the fine tin-stone and fine sand into a transverse +trough, from which the water flows down through the spouts, which pierce +the side of the trough, into the one or other of the large buddles set +underneath. The reason why there are two is that, while the washer +empties the one which is filled with fine tin-stone and sand, the +material may flow into the other. Each buddle is twelve feet long, one +cubit deep, and a foot and a half broad. The tin-stone which settles in +the upper part of the buddles is called the large size; these are +frequently stirred with a shovel, in order that the medium sized +particles of tin-stone, and the mud mixed with the very fine particles +of the stones may flow away. The particles of medium size generally +settle in the middle part of the buddle, where they are arrested by +interwoven fir twigs. The mud which flows down with the water settles +between the twigs and the board which closes the lower end of the +buddle. The tin-stone of large size is removed separately from the +buddle with a shovel; those of medium size are also removed separately, +and likewise the mud is removed separately, for they are separately +washed on the canvas strakes and on the ordinary strake, and separately +roasted and smelted. The tin-stone which has settled in the middle part +of the buddle, is also always washed separately on the canvas strakes; +but if the particles are nearly equal in size to those which have +settled in the upper part of the buddle, they are washed with them in +the ordinary strake and are roasted and smelted with them. However, the +mud is never washed with the others, either on the canvas strakes or on +the ordinary strake, but separately, and the fine tin-stone which is +obtained from it is roasted and smelted separately. The two large +buddles discharge into a cross trough, and it again empties through a +launder into a settling-pit which is outside the building. + +This method of washing has lately undergone a considerable change; for +the launder which carries the water, mixed with the crushed tin-stone +and fine sand which flow from the openings of the screen, does not reach +to a transverse trough which is inside the same room, but runs straight +through a partition into a small settling-pit. A boy draws a +three-toothed rake through the material which has settled in the portion +of the launder outside the room, by which means the larger sized +particles of tin-stone settle at the bottom, and these the washer takes +out with the wooden shovel and carries into the room; this material is +thrown into an ordinary strake and swept with a wooden scrubber and +washed. As for those tin-stone particles which the water carries off +from the strake, after they have been brought back on to the strake, he +washes them again until they are clean. + +[Illustration 315 (Buddle): A--First launder. B--Three-toothed rake. +C--Small settling pit. D--Large buddle. E--Buddle resembling the simple +buddle. F--Small roller. G--Boards. H--Their holes. I--Shovel. +K--Building. L--Stove. (This picture does not entirely agree with the +text).] + +The remaining tin-stone, mixed with sand, flows into the small +settling-pit which is within the building, and this discharges into two +large buddles. The tin-stone of moderate size, mixed with those of +fairly large size, settle in the upper part, and the small size in the +lower part; but both are impure, and for this reason they are taken out +separately and the former is washed twice, first in a buddle like the +simple buddle, and afterward on an ordinary strake. Likewise the latter +is washed twice, first on a canvas strake and afterward on an ordinary +strake. This buddle, which is like the simple buddle, differs from it in +the head, the whole of which in this case is sloping, while in the case +of the other it is depressed in the centre. In order that the boy may be +able to rest the shovel with which he cleanses the tin-stone, this +sluice has a small wooden roller which turns in holes in two thick +boards fixed to the sides of the buddle; if he did not do this, he would +become over-exhausted by his task, for he spends whole days standing +over these labours. The large buddle, the one like the simple buddle, +the ordinary strake, and the canvas strakes, are erected within a +special building. In this building there is a stove that gives out heat +through the earthen tiles or iron plates of which it is composed, in +order that the washers can pursue their labours even in winter, if the +rivers are not completely frozen over. + +[Illustration 317 (Workroom with settling-pit): A--Launder from the +screen of the mortar-box. B--Three-toothed rake. C--Small settling-pit. +D--Canvas. E--Strakes. F--Brooms.] + +On the canvas strakes are washed the very fine tin-stone mixed with mud +which has settled in the lower end of the large buddle, as well as in +the lower end of the simple buddle and of the ordinary strake. The +canvas is cleaned in a trough hewn out of one tree trunk and partitioned +off with two boards, so that three compartments are made. The first and +second pieces of canvas are washed in the first compartment, the third +and fourth in the second compartment, the fifth and sixth in the third +compartment. Since among the very fine tin-stone there are usually some +grains of stone, rock, or marble, the master cleanses them on the +ordinary strake, lightly brushing the top of the material with a broom, +the twigs of which do not all run the same way, but some straight and +some crosswise. In this way the water carries off these impurities from +the strake into the settling-pit because they are lighter, and leaves +the tin-stone on the table because it is heavier. + +Below all buddles or strakes, both inside and outside the building, +there are placed either settling-pits or cross-troughs into which they +discharge, in order that the water may carry on down into the stream but +very few of the most minute particles of tin-stone. The large +settling-pit which is outside the building is generally made of joined +flooring, and is eight feet in length, breadth and depth. When a large +quantity of mud, mixed with very fine tin-stone, has settled in it, +first of all the water is let out by withdrawing a plug, then the mud +which is taken out is washed outside the house on the canvas strakes, +and afterward the concentrates are washed on the strake which is inside +the building. By these methods the very finest tin-stone is made clean. + +[Illustration 318 (Streaming for Tin): A--River. B--Weir. C--Gate. +D--Area. E--Meadow. F--Fence. G--Ditch.] + +The mud mixed with the very fine tin-stone, which has neither settled in +the large settling-pit nor in the transverse launder which is outside +the room and below the canvas strakes, flows away and settles in the bed +of the stream or river. In order to recover even a portion of the fine +tin-stone, many miners erect weirs in the bed of the stream or river, +very much like those that are made above the mills, to deflect the +current into the races through which it flows to the water-wheels. At +one side of each weir there is an area dug out to a depth of five or six +or seven feet, and if the nature of the place will permit, extending +in every direction more than sixty feet. Thus, when the water of the +river or stream in autumn and winter inundates the land, the gates of +the weir are closed, by which means the current carries the mud mixed +with fine tin-stone into the area. In spring and summer this mud is +washed on the canvas strakes or on the ordinary strake, and even the +finest black-tin is collected. Within a distance of four thousand +fathoms along the bed of the stream or river below the buildings in +which the tin-stuff is washed, the miners do not make such weirs, but +put inclined fences in the meadows, and in front of each fence they dig +a ditch of the same length, so that the mud mixed with the fine +tin-stone, carried along by the stream or river when in flood, may +settle in the ditch and cling to the fence. When this mud is collected, +it is likewise washed on canvas strakes and on the ordinary strake, in +order that the fine tin-stone may be separated from it. Indeed we may +see many such areas and fences collecting mud of this kind in Meissen +below Altenberg in the river Moglitz,--which is always of a reddish +colour when the rock containing the black tin is being crushed under the +stamps. + +[Illustration 320 (Stamp-mill): A--First machine. B--Its stamps. C--Its +mortar-box. D--Second machine. E--Its stamps. F--Its mortar-box. +G--Third machine. H--Its stamps. I--Its mortar-box. K--Fourth machine. +L--Its stamps. M--Its mortar-box.] + +But to return to the stamping machines. Some usually set up four +machines of this kind in one place, that is to say, two above and the +same number below. By this plan it is necessary that the current which +has been diverted should fall down from a greater height upon the upper +water-wheels, because these turn axles whose cams raise heavier stamps. +The stamp-stems of the upper machines should be nearly twice as long as +the stems of the lower ones, because all the mortar-boxes are placed on +the same level. These stamps have their tappets near their upper ends, +not as in the case of the lower stamps, which are placed just above the +bottom. The water flowing down from the two upper water-wheels is caught +in two broad races, from which it falls on to the two lower +water-wheels. Since all these machines have the stamps very close +together, the stems should be somewhat cut away, to prevent the iron +shoes from rubbing each other at the point where they are set into the +stems. Where so many machines cannot be constructed, by reason of the +narrowness of the valley, the mountain is excavated and levelled in two +places, one of which is higher than the other, and in this case two +machines are constructed and generally placed in one building. A broad +race receives in the same way the water which flows down from the upper +water-wheel, and similarly lets it fall on the lower water-wheel. The +mortar-boxes are not then placed on one level, but each on the level +which is appropriate to its own machine, and for this reason, two +workmen are then required to throw ore into the mortar-boxes. When no +stream can be diverted which will fall from a higher place upon the top +of the water-wheel, one is diverted which will turn the foot of the +wheel; a great quantity of water from the stream is collected in one +pool capable of holding it, and from this place, when the gates are +raised, the water is discharged against the wheel which turns in the +race. The buckets of a water-wheel of this kind are deeper and bent +back, projecting upward; those of the former are shallower and bent +forward, inclining downward. + +[Illustration 321 (Stamp-mill): A--Stamps. B--Mortar. C--Plates full of +holes. D--Transverse launder. E--Planks full of cup-like depressions. +F--Spout. G--Bowl into which the concentrates fall. H--Canvas strake. +I--Bowls shaped like a small boat. K--Settling-pit under the canvas +strake.] + +Further, in the Julian and Rhaetian Alps[15] and in the Carpathian +Mountains, gold or even silver ore is now put under stamps, which are +sometimes placed more than twenty in a row, and crushed wet in a long +mortar-box. The mortar has two plates full of holes through which the +ore, after being crushed, flows out with the water into the transverse +launder placed underneath, and from there it is carried down by two +spouts into the heads of the canvas strakes. Each head is made of a +thick broad plank, which can be raised and set upright, and to which on +each side are fixed pieces projecting upward. In this plank there are +many cup-like depressions equal in size and similar in shape, in each of +which an egg could be placed. Right down in these depressions are small +crevices which can retain the concentrates of gold or silver, and when +the hollows are nearly filled with these materials, the plank is raised +on one side so that the concentrates will fall into a large bowl. The +cup-like depressions are washed out by dashing them with water. These +concentrates are washed separately in different bowls from those which +have settled on the canvas. This bowl is smooth and two digits wide and +deep, being in shape very similar to a small boat; it is broad in the +fore part, narrow in the back, and in the middle of it there is a cross +groove, in which the particles of pure gold or silver settle, while the +grains of sand, since they are lighter, flow out of it. + +In some parts of Moravia, gold ore, which consists of quartz mixed with +gold, is placed under the stamps and crushed wet. When crushed fine it +flows out through a launder into a trough, is there stirred by a wooden +scrubber, and the minute particles of gold which settle in the upper end +of the trough are washed in a black bowl. + +So far I have spoken of machines which crush wet ore with iron-shod +stamps. I will now explain the methods of washing which are in a measure +peculiar to the ore of certain metals, beginning with gold. The ore +which contains particles of this metal, and the sand of streams and +rivers which contains grains of it, are washed in frames or bowls; the +sands especially are also washed in troughs. More than one method is +employed for washing on frames, for these frames either pass or retain +the particles or concentrates of gold; they pass them if they have +holes, and retain them if they have no holes. But either the frame +itself has holes, or a box is substituted for it; if the frame itself is +perforated it passes the particles or concentrates of gold into a +trough; if the box has them, it passes the gold material into the long +sluice. I will first speak of these two methods of washing. The frame is +made of two planks joined together, and is twelve feet long and three +feet wide, and is full of holes large enough for a pea to pass. To +prevent the ore or sand with which the gold is mixed from falling out at +the sides, small projecting edge-boards are fixed to it. This frame is +set upon two stools, the first of which is higher than the second, in +order that the gravel and small stones can roll down it. The washer +throws the ore or sand into the head of the frame, which is higher, and +opening the small launder, lets the water into it, and then agitates it +with a wooden scrubber. In this way, the gravel and small stones roll +down the frame on to the ground, while the particles or concentrates of +gold, together with the sand, pass through the holes into the trough +which is placed under the frame, and after being collected are washed in +the bowl. + +[Illustration 322 (Frames for Washing Ore or Alluvial): A--Head of +frame. B--Frame. C--Holes. D--Edge-boards. E--Stools. F--Scrubber. +G--Trough. H--Launder. I--Bowl.] + +[Illustration 323 (Frames for Washing Ore or Alluvial): A--Sluice. +B--Box. C--Bottom of inverted box. D--Open part of it. E--Iron hoe. +F--Riffles. G--Small launder. H--Bowl with which settlings are taken +away. I--Black bowl in which they are washed.] + +A box which has a bottom made of a plate full of holes, is placed over +the upper end of a sluice, which is fairly long but of moderate width. +The gold material to be washed is thrown into this box, and a great +quantity of water is let in. The lumps, if ore is being washed, are +mashed with an iron shovel. The fine portions fall through the bottom of +the box into the sluice, but the coarse pieces remain in the box, and +these are removed with a scraper through an opening which is nearly in +the middle of one side. Since a large amount of water is necessarily let +into the box, in order to prevent it from sweeping away any particles of +gold which have fallen into the sluice, the sluice is divided off by +ten, or if it is as long again, by fifteen riffles. These riffles are +placed equidistant from one another, and each is higher than the one +next toward the lower end of the sluice. The little compartments which +are thus made are filled with the material and the water which flows +through the box; as soon as these compartments are full and the water +has begun to flow over clear, the little launder through which this +water enters into the box is closed, and the water is turned in another +direction. Then the lowest riffle is removed from the sluice, and the +sediment which has accumulated flows out with the water and is caught in +a bowl. The riffles are removed one by one and the sediment from each is +taken into a separate bowl, and each is separately washed and cleansed +in a bowl. The larger particles of gold concentrates settle in the +higher compartments, the smaller size, in the lower compartments. This +bowl is shallow and smooth, and smeared with oil or some other slippery +substance, so that the tiny particles of gold may not cling to it, and +it is painted black, that the gold may be more easily discernible; on +the exterior, on both sides and in the middle, it is slightly hollowed +out in order that it may be grasped and held firmly in the hands when +shaken. By this method the particles or concentrates of gold settle in +the back part of the bowl; for if the back part of the bowl is tapped or +shaken with one hand, as is usual, the contents move toward the fore +part. In this way the Moravians, especially, wash gold ore. + +The gold particles are also caught on frames which are either bare or +covered. If bare, the particles are caught in pockets; if covered, they +cling to the coverings. Pockets are made in various ways, either with +iron wire or small cross-boards fixed to the frame, or by holes which +are sunk into the sluice itself or into its head, but which do not quite +go through. These holes are round or square, or are grooves running +crosswise. The frames are either covered with skins, pieces of cloth, or +turf, which I will deal with one by one in turn. + +[Illustration 324 (Frames for Washing Ore or Alluvial): A--Plank. +B--Side-boards. C--Iron wire. D--Handles.] + +In order to prevent the sand which contains the particles of gold from +spilling out, the washer fixes side-boards to the edges of a plank which +is six feet long and one and a quarter wide. He then lays crosswise many +iron wires a digit apart, and where they join he fixes them to the +bottom plank with iron nails. Then he makes the head of the frame +higher, and into this he throws the sand which needs washing, and taking +in his hands the handles which are at the head of the frame, he draws it +backward and forward several times in the river or stream. In this way +the small stones and gravel flow down along the frame, and the sand +mixed with particles of gold remains in the pockets between the strips. +When the contents of the pockets have been shaken out and collected in +one place, he washes them in a bowl and thus cleans the gold dust. + +[Illustration 326 (Frames for Washing Ore or Alluvial): A--Head of the +sluice. B--Riffles. C--Wooden scrubber. D--Pointed stick. E--Dish. +F--Its cup-like depression. G--Grooved dish.] + +Other people, among whom are the Lusitanians[16], fix to the sides of a +sluice, which is about six feet long and a foot and a half broad, many +cross-strips or riffles, which project backward and are a digit apart. +The washer or his wife lets the water into the head of the sluice, where +he throws the sand which contains the particles of gold. As it flows +down he agitates it with a wooden scrubber, which he moves transversely +to the riffles. He constantly removes with a pointed wooden stick the +sediment which settles in the pockets between the riffles, and in this +way the particles of gold settle in them, while the sand and other +valueless materials are carried by the water into a tub placed below the +sluice. He removes the particles of metal with a small wooden shovel +into a wooden bowl. This bowl does not exceed a foot and a quarter in +breadth, and by moving it up and down in the stream he cleanses the gold +dust, for the remaining sand flows out of the dish, and the gold dust +settles in the middle of it, where there is a cup-like depression. Some +make use of a bowl which is grooved inside like a shell, but with a +smooth lip where the water flows out. This smooth place, however, is +narrower where the grooves run into it, and broader where the water +flows out. + +[Illustration 327 (Frames for Washing Ore or Alluvial): A--Head of the +sluice. B--Side-boards. C--Lower end of the sluice. D--Pockets. +E--Grooves. F--Stools. G--Shovel. H--Tub set below. I--Launder.] + +The cup-like pockets and grooves are cut or burned at the same time into +the bottom of the sluice; the bottom is composed of three planks ten +feet long, and is about four feet wide; but the lower end, through which +the water is discharged, is narrower. This sluice, which likewise has +side-boards fixed to its edges, is full of rounded pockets and of +grooves which lead to them, there being two grooves to one pocket, in +order that the water mixed with sand may flow into each pocket through +the upper groove, and that after the sand has partly settled, the water +may again flow out through the lower groove. The sluice is set in the +river or stream or on the bank, and placed on two stools, of which the +first is higher than the second in order that the gravel and small +stones may roll down the sluice. The washer throws sand into the head +with a shovel, and opening the launder, lets in the water, which carries +the particles of metal with a little sand down into the pockets, while +the gravel and small stones with the rest of the sand falls into a tub +placed below the sluice. As soon as the pockets are filled, he brushes +out the concentrates and washes them in a bowl. He washes again and +again through this sluice. + +[Illustration 328 (Frames for Washing Ore or Alluvial): A--Cross +grooves. B--Tub set under the sluice. C--Another tub.] + +Some people cut a number of cross-grooves, one palm distant from each +other, in a sluice similarly composed of three planks eight feet long. +The upper edge of these grooves is sloping, that the particles of gold +may slip into them when the washer stirs the sand with a wooden shovel; +but their lower edge is vertical so that the gold particles may thus be +unable to slide out of them. As soon as these grooves are full of gold +particles mixed with fine sand, the sluice is removed from the stools +and raised up on its head. The head in this case is nothing but the +upper end of the planks of which the sluice is composed. In this way the +metallic particles, being turned over backward, fall into another tub, +for the small stones and gravel have rolled down the sluice. Some people +place large bowls under the sluice instead of tubs, and as in the other +cases, the unclean concentrates are washed in the small bowl. + +[Illustration 329 (Frames for Washing Ore or Alluvial): A--Sluice +covered with canvas. B--Its head full of pockets and grooves. C--Head +removed and washed in a tub. D--Sluice which has square pockets. +E--Sluice to whose planks small shavings cling. F--Broom. G--Skins of +oxen. H--Wooden scrubber.] + +The Thuringians cut rounded pockets, a digit in diameter and depth, in +the head of the sluice, and at the same time they cut grooves reaching +from one to another. The sluice itself they cover with canvas. The sand +which is to be washed, is thrown into the head and stirred with a +wooden scrubber; in this way the water carries the light particles of +gold on to the canvas, and the heavy ones sink in the pockets, and when +these hollows are full, the head is removed and turned over a tub, and +the concentrates are collected and washed in a bowl. Some people make +use of a sluice which has square pockets with short vertical recesses +which hold the particles of gold. Other workers use a sluice made of +planks, which are rough by reason of the very small shavings which still +cling to them; these sluices are used instead of those with coverings, +of which this sluice is bare, and when the sand is washed, the particles +of gold cling no less to these shavings than to canvas, or skins, or +cloths, or turf. The washer sweeps the sluice upward with a broom, and +when he has washed as much of the sand as he wishes, he lets a more +abundant supply of water into the sluice again to wash out the +concentrates, which he collects in a tub set below the sluice, and then +washes again in a bowl. Just as Thuringians cover the sluice with +canvas, so some people cover it with the skins of oxen or horses. They +push the auriferous sand upward with a wooden scrubber, and by this +system the light material flows away with the water, while the particles +of gold settle among the hairs; the skins are afterward washed in a tub; +and the concentrates are collected in a bowl. + +[Illustration 330 (Washing material in spring): A--Spring. B--Skin. +C--Argonauts.] + +The Colchians[17] placed the skins of animals in the pools of springs; +and since many particles of gold had clung to them when they were +removed, poets invented the "golden fleece" of the Colchians. In like +manner, it can be contrived by the methods of miners that skins should +take up, not only particles of gold, but also of silver and gems. + +[Illustration 331 (Frames for Washing Ore or Alluvial): A--Head of +frame. B--Frame. C--Cloth. D--small launder. E--Tub set below the frame. +F--Tub in which cloth is washed.] + +Many people cover the frame with a green cloth as long and wide as the +frame itself, and fasten it with iron nails in such a way that they can +easily draw them out and remove the cloth. When the cloth appears to be +golden because of the particles which adhere to it, it is washed in a +special tub and the particles are collected in a bowl. The remainder +which has run down into the tub is again washed on the frame. + +[Illustration 332 (Frames for Washing Ore or Alluvial): A--Cloth full +of small knots, spread out. B--Small knots more conspicuously shown. +C--Tub in which cloth is washed.] + +Some people, in place of a green cloth, use a cloth of tightly woven +horsehair, which has a rough knotty surface. Since these knots stand out +and the cloth is rough, even the very small particles of gold adhere to +it; these cloths are likewise washed in a tub with water. + +[Illustration 333 (Frames for Washing Ore or Alluvial): A--Head of +frame. B--Small launder through which water flows into head of frame. +C--Pieces of turf. D--Trough placed under frame. E--Tub in which pieces +of turf are washed.] + +Some people construct a frame not unlike the one covered with canvas, +but shorter. In place of the canvas they set pieces of turf in rows. +They wash the sand, which has been thrown into the head of the frame, by +letting in water. In this way the particles of gold settle in the turf, +the mud and sand, together with the water, are carried down into the +settling-pit or trough below, which is opened when the work is finished. +After all the water has passed out of the settling-pit, the sand and mud +are carried away and washed over again in the same manner. The particles +which have clung to the turf are afterward washed down into the +settling-pit or trough by a stronger current of the water, which is let +into the frame through a small launder. The concentrates are finally +collected and washed in a bowl. Pliny was not ignorant of this method of +washing gold. "The ulex," he says, "after being dried, is burnt, and its +ashes are washed over a grassy turf, that the gold may settle on it." + +[Illustration 334 (Trays for Washing Alluvial): A--Tray. B--Bowl-like +depression. C--Handles.] + +Sand mixed with particles of gold is also washed in a tray, or in a +trough or bowl. The tray is open at the further end, is either hewn out +of a squared trunk of a tree or made out of a thick plank to which +side-boards are fixed, and is three feet long, a foot and a half wide, +and three digits deep. The bottom is hollowed out into the shape of an +elongated bowl whose narrow end is turned toward the head, and it has +two long handles, by which it is drawn backward and forward in the +river. In this way the fine sand is washed, whether it contains +particles of gold or the little black stones from which tin is made. + +[Illustration 335 (Trough for washing alluvial): A--Trough. B--Its open +end. C--End that may be closed. D--Stream. E--Hoe. F--End-board. +G--Bag.] + +The Italians who come to the German mountains seeking gold, in order to +wash the river sand which contains gold-dust and garnets,[19] use a +fairly long shallow trough hewn out of a tree, rounded within and +without, open at one end and closed at the other, which they turn in the +bed of the stream in such a way that the water does not dash into it, +but flows in gently. They stir the sand, which they throw into it, with +a wooden hoe, also rounded. To prevent the particles of gold or garnets +from running out with the light sand, they close the end with a board +similarly rounded, but lower than the sides of the trough. The +concentrates of gold or garnets which, with a small quantity of heavy +sand, have settled in the trough, they wash in a bowl and collect in +bags and carry away with them. + +[Illustration 336 (Bowls for Alluvial Washing): A--Large bowl. B--Ropes. +C--Beam. D--Other large bowl which coiners use. E--Small bowl.] + +Some people wash this kind of sand in a large bowl which can easily be +shaken, the bowl being suspended by two ropes from a beam in a building. +The sand is thrown into it, water is poured in, then the bowl is shaken, +and the muddy water is poured out and clear water is again poured in, +this being done again and again. In this way, the gold particles settle +in the back part of the bowl because they are heavy, and the sand in the +front part because it is light; the latter is thrown away, the former +kept for smelting. The one who does the washing then returns immediately +to his task. This method of washing is rarely used by miners, but +frequently by coiners and goldsmiths when they wash gold, silver, or +copper. The bowl they employ has only three handles, one of which they +grasp in their hands when they shake the bowl, and in the other two is +fastened a rope by which the bowl is hung from a beam, or from a +cross-piece which is upheld by the forks of two upright posts fixed in +the ground. Miners frequently wash ore in a small bowl to test it. This +bowl, when shaken, is held in one hand and thumped with the other hand. +In other respects this method of washing does not differ from the last. + +[Illustration 337 (Ground Sluicing): A--Stream. B--Ditch. C--Mattock. +D--Pieces of turf. E--Seven-pronged fork. F--Iron shovel. G--Trough. +H--Another trough below it. I--Small wooden trowel.] + +I have spoken of the various methods of washing sand which contains +grains of gold; I will now speak of the methods of washing the material +in which are mixed the small black stones from which tin is made[20]. +Eight such methods are in use, and of these two have been invented +lately. Such metalliferous material is usually found torn away from +veins and stringers and scattered far and wide by the impetus of water, +although sometimes _venae dilatatae_ are composed of it. The miners dig +out the latter material with a broad mattock, while they dig the former +with a pick. But they dig out the little stones, which are not rare in +this kind of ore, with an instrument like the bill of a duck. In +districts which contain this material, if there is an abundant supply of +water, and if there are valleys or gentle slopes and hollows, so that +rivers can be diverted into them, the washers in summer-time first of +all dig a long ditch sloping so that the water will run through it +rapidly. Into the ditch is thrown the metallic material, together with +the surface material, which is six feet thick, more or less, and often +contains moss, roots of plants, shrubs, trees, and earth; they are all +thrown in with a broad mattock, and the water flows through the ditch. +The sand and tin-stone, as they are heavy, sink to the bottom of the +ditch, while the moss and roots, as they are light, are carried away by +the water which flows through the ditch. The bottom of the ditch is +obstructed with turf and stones in order to prevent the water from +carrying away the tin-stone at the same time. The washers, whose feet +are covered with high boots made of hide, though not of rawhide, +themselves stand in the ditch and throw out of it the roots of the +trees, shrubs, and grass with seven-pronged wooden forks, and push back +the tin-stone toward the head of the ditch. After four weeks, in which +they have devoted much work and labour, they raise the tin-stone in the +following way; the sand with which it is mixed is repeatedly lifted from +the ditch with an iron shovel and agitated hither and thither in the +water, until the sand flows away and only the tin-stone remains on the +shovel. The tin-stone is all collected together and washed again in a +trough by pushing it up and turning it over with a wooden trowel, in +order that the remaining sand may separate from it. Afterward they +return to their task, which they continue until the metalliferous +material is exhausted, or until the water can no longer be diverted into +the ditches. + +[Illustration 338 (Sluicing Tin): A--Trough. B--Wooden shovel. C--Tub. +D--Launder. E--Wooden trowel. F--Transverse trough. G--Plug. H--Falling +water. I--Ditch. K--Barrow conveying material to be washed. L--Pick like +the beak of a duck with which the miner digs out the material from which +the small stones are obtained.] + +The trough which I mentioned is hewn out of the trunk of a tree and the +interior is five feet long, three-quarters of a foot deep, and six +digits wide. It is placed on an incline and under it is put a tub which +contains interwoven fir twigs, or else another trough is put under it, +the interior of which is three feet long and one foot wide and deep; the +fine tin-stone, which has run out with the water, settles in the bottom. +Some people, in place of a trough, put a square launder underneath, and +in like manner they wash the tin-stone in this by agitating it up and +down and turning it over with a small wooden trowel. A transverse trough +is put under the launder, which is either open on one end and drains off +into a tub or settling-pit, or else is closed and perforated through the +bottom; in this case, it drains into a ditch beneath, where the water +falls when the plug has been partly removed. The nature of this ditch I +will now describe. + +[Illustration 340 (Sluicing Tin): A--Launder. B--Interlacing fir twigs. +C--Logs; three on one side, for the fourth cannot be seen because the +ditch is so full with material now being washed. D--Logs at the head of +the ditch. E--Barrow. F--Seven-pronged fork. G--Hoe.] + +If the locality does not supply an abundance of water, the washers dig a +ditch thirty or thirty-six feet long, and cover the bottom, the full +length, with logs joined together and hewn on the side which lies flat +on the ground. On each side of the ditch, and at its head also, they +place four logs, one above the other, all hewn smooth on the inside. But +since the logs are laid obliquely along the sides, the upper end of the +ditch is made four feet wide and the tail end, two feet. The water has a +high drop from a launder and first of all it falls into interlaced fir +twigs, in order that it shall fall straight down for the most part in an +unbroken stream and thus break up the lumps by its weight. Some do not +place these twigs under the end of the launder, but put a plug in its +mouth, which, since it does not entirely close the launder, nor +altogether prevent the discharge from it, nor yet allow the water to +spout far afield, makes it drop straight down. The workman brings in a +wheelbarrow the material to be washed, and throws it into the ditch. The +washer standing in the upper end of the ditch breaks the lumps with a +seven-pronged fork, and throws out the roots of trees, shrubs, and grass +with the same instrument, and thereby the small black stones settle +down. When a large quantity of the tin-stone has accumulated, which +generally happens when the washer has spent a day at this work, to +prevent it from being washed away he places it upon the bank, and other +material having been again thrown into the upper end of the ditch, he +continues the task of washing. A boy stands at the lower end of the +ditch, and with a thin pointed hoe stirs up the sediment which has +settled at the lower end, to prevent the washed tin-stone from being +carried further, which occurs when the sediment has accumulated to such +an extent that the fir branches at the outlet of the ditch are covered. + +[Illustration 341 (Sifting Ore): A--Strakes. B--Tank. C--Launder. +D--Plug. E--Wooden shovel. F--Wooden mallet. G--Wooden shovel with short +handle. H--The plug in the strake. I--Tank placed under the plug.] + +The third method of washing materials of this kind follows. Two strakes +are made, each of which is twelve feet long and a foot and a half wide +and deep. A tank is set at their head, into which the water flows +through a little launder. A boy throws the ore into one strake; if it is +of poor quality he puts in a large amount of it, if it is rich he puts +in less. The water is let in by removing the plug, the ore is stirred +with a wooden shovel, and in this way the tin-stone, mixed with the +heavier material, settles in the bottom of the strake, and the water +carries the light material into the launder, through which it flows on +to a canvas strake. The very fine tin-stone, carried by the water, +settles on to the canvas and is cleansed. A low cross-board is placed in +the strake near the head, in order that the largest sized tin-stone may +settle there. As soon as the strake is filled with the material which +has been washed, he closes the mouth of the tank and continues washing +in the other strake, and then the plug is withdrawn and the water and +tin-stone flow down into a tank below. Then he pounds the sides of the +loaded strake with a wooden mallet, in order that the tin-stone clinging +to the sides may fall off; all that has settled in it, he throws out +with a wooden shovel which has a short handle. Silver slags which have +been crushed under the stamps, also fragments of silver-lead alloy and +of cakes melted from pyrites, are washed in a strake of this kind. + +[Illustration 342 (Sifting Ore): A--Sieve. B--Tub. C--Water flowing out +of the bottom of it. D--Strake. E--Three-toothed rake. F--Wooden +scrubber.] + +Material of this kind is also washed while wet, in a sieve whose bottom +is made of woven iron wire, and this is the fourth method of washing. +The sieve is immersed in the water which is contained in a tub, and is +violently shaken. The bottom of this tub has an opening of such size +that as much water, together with tailings from the sieve, can flow +continuously out of it as water flows into it. The material which +settles in the strake, a boy either digs over with a three-toothed iron +rake or sweeps with a wooden scrubber; in this way the water carries off +a great part of both sand and mud. The tin-stone or metalliferous +concentrates settle in the strake and are afterward washed in another +strake. + +[Illustration 343 (Sluicing Tin): A--Box. B--Perforated plate. +C--Trough. D--Cross-boards. E--Pool. F--Launder. G--Shovel. H--Rake.] + +These are ancient methods of washing material which contains tin-stone; +there follow two modern methods. If the tin-stone mixed with earth or +sand is found on the slopes of mountains or hills, or in the level +fields which are either devoid of streams or into which a stream cannot +be diverted, miners have lately begun to employ the following method of +washing, even in the winter months. An open box is constructed of +planks, about six feet long, three feet wide, and two feet and one palm +deep. At the upper end on the inside, an iron plate three feet long and +wide is fixed, at a depth of one foot and a half from the top; this +plate is very full of holes, through which tin-stone about the size of a +pea can fall. A trough hewn from a tree is placed under the box, and +this trough is about twenty-four feet long and three-quarters of a foot +wide and deep; very often three cross-boards are placed in it, dividing +it off into compartments, each one of which is lower than the next. The +turbid waters discharge into a settling-pit. + +The metalliferous material is sometimes found not very deep beneath the +surface of the earth, but sometimes so deep that it is necessary to +drive tunnels and sink shafts. It is transported to the washing-box in +wheelbarrows, and when the washers are about to begin they lay a small +launder, through which there flows on to the iron plate so much water +as is necessary for this washing. Next, a boy throws the metalliferous +material on to the iron plate with an iron shovel and breaks the small +lumps, stirring them this way and that with the same implement. Then the +water and sand penetrating the holes of the plate, fall into the box, +while all the coarse gravel remains on the plate, and this he throws +into a wheelbarrow with the same shovel. Meantime, a younger boy +continually stirs the sand under the plate with a wooden scrubber nearly +as wide as the box, and drives it to the upper end of the box; the +lighter material, as well as a small amount of tin-stone, is carried by +the water down into the underlying trough. The boys carry on this labour +without intermission until they have filled four wheelbarrows with the +coarse and worthless residues, which they carry off and throw away, or +three wheelbarrows if the material is rich in black tin. Then the +foreman has the plank removed which was in front of the iron plate, and +on which the boy stood. The sand, mixed with the tin-stone, is +frequently pushed backward and forward with a scrubber, and the same +sand, because it is lighter, takes the upper place, and is removed as +soon as it appears; that which takes the lower place is turned over with +a spade, in order that any that is light can flow away; when all the +tin-stone is heaped together, he shovels it out of the box and carries +it away. While the foreman does this, one boy with an iron hoe stirs the +sand mixed with fine tin-stone, which has run out of the box and has +settled in the trough and pushes it back to the uppermost part of the +trough, and this material, since it contains a very great amount of +tin-stone, is thrown on to the plate and washed again. The material +which has settled in the lowest part of the trough is taken out +separately and piled in a heap, and is washed on the ordinary strake; +that which has settled in the pool is washed on the canvas strake. In +the summer-time this fruitful labour is repeated more often, in fact ten +or eleven times. The tin-stone which the foreman removes from the box, +is afterward washed in a jigging sieve, and lastly in a tub, where at +length all the sand is separated out. Finally, any material in which are +mixed particles of other metals, can be washed by all these methods, +whether it has been disintegrated from veins or stringers, or whether it +originated from _venae dilatatae_, or from streams and rivers. + +[Illustration 345 (Ground Sluicing): A--Launder. B--Cross trough. C--Two +spouts. D--Boxes. E--Plate. F--Grating. G--Shovels. H--Second cross +trough. I--Strake. K--Wooden scrubber. L--Third cross trough. +M--Launder. N--Three-toothed rake.] + +The sixth method of washing material of this kind is even more modern +and more useful than the last. Two boxes are constructed, into each of +which water flows through spouts from a cross trough into which it has +been discharged through a pipe or launder. When the material has been +agitated and broken up with iron shovels by two boys, part of it runs +down and falls through the iron plates full of holes, or through the +iron grating, and flows out of the box over a sloping surface into +another cross trough, and from this into a strake seven feet long and +two and a half feet wide. Then the foreman again stirs it with a wooden +scrubber that it may become clean. As for the material which has flowed +down with the water and settled in the third cross trough, or in the +launder which leads from it, a third boy rakes it with a two-toothed +rake; in this way the fine tin-stone settles down and the water carries +off the valueless sand into the creek. This method of washing is most +advantageous, for four men can do the work of washing in two boxes, +while the last method, if doubled, requires six men, for it requires two +boys to throw the material to be washed on to the plate and to stir it +with iron shovels; two more are required with wooden scrubbers to keep +stirring the sand, mixed with the tin-stone, under the plate, and to +push it toward the upper end of the box; further, two foremen are +required to clean the tin-stone in the way I have described. In the +place of a plate full of holes, they now fix in the boxes a grating made +of iron wire as thick as the stalks of rye; that these may not be +depressed by the weight and become bent, three iron bars support them, +being laid crosswise underneath. To prevent the grating from being +broken by the iron shovels with which the material is stirred in +washing, five or six iron rods are placed on top in cross lines, and are +fixed to the box so that the shovels may rub them instead of the +grating; for this reason the grating lasts longer than the plates, +because it remains intact, while the rods, when worn by rubbing, can +easily be replaced by others. + +[Illustration 346 (Ground Sluicing): A--Pits. B--Torrent. +C--Seven-pronged fork. D--Shovel.] + +Miners use the seventh method of washing when there is no stream of +water in the part of the mountain which contains the black tin, or +particles of gold, or of other metals. In this case they frequently dig +more than fifty ditches on the slope below, or make the same number of +pits, six feet long, three feet wide, and three-quarters of a foot deep, +not any great distance from each other. At the season when a torrent +rises from storms of great violence or long duration, and rushes down +the mountain, some of the miners dig the metalliferous material in the +woods with broad hoes and drag it to the torrent. Other miners divert +the torrent into the ditches or pits, and others throw the roots of +trees, shrubs, and grass out of the ditches or pits with seven-pronged +wooden forks. When the torrent has run down, they remove with shovels +the uncleansed tin-stone or particles of metal which have settled in the +ditches or pits, and cleanse it. + +[Illustration 347 (Ground Sluicing): A--Gully. B--Ditch. C--Torrent. +D--Sluice box employed by the Lusitanians.] + +The eighth method is also employed in the regions which the Lusitanians +hold in their power and sway, and is not dissimilar to the last. They +drive a great number of deep ditches in rows in the gullies, slopes, +and hollows of the mountains. Into these ditches the water, whether +flowing down from snow melted by the heat of the sun or from rain, +collects and carries together with earth and sand, sometimes tin-stone, +or, in the case of the Lusitanians, the particles of gold loosened from +veins and stringers. As soon as the waters of the torrent have all run +away, the miners throw the material out of the ditches with iron +shovels, and wash it in a common sluice box. + +[Illustration 348 (Trough for washing alluvial): A--Trough. B--Launder. +C--Hoe. D--Sieve.] + +The Poles wash the impure lead from _venae dilatatae_ in a trough ten +feet long, three feet wide, and one and one-quarter feet deep. It is +mixed with moist earth and is covered by a wet and sandy clay, and so +first of all the clay, and afterward the ore, is dug out. The ore is +carried to a stream or river, and thrown into a trough into which water +is admitted by a little launder, and the washer standing at the lower +end of the trough drags the ore out with a narrow and nearly pointed +hoe, whose wooden handle is nearly ten feet long. It is washed over +again once or twice in the same way and thus made pure. Afterward when +it has been dried in the sun they throw it into a copper sieve, and +separate the very small pieces which pass through the sieve from the +larger ones; of these the former are smelted in a faggot pile and the +latter in the furnace. Of such a number then are the methods of washing. + +[Illustration 349 (Tin burning Furnace): A--Furnace. B--Its mouth. +C--Poker. D--Rake with two teeth. E--Hoe.] + +One method of burning is principally employed, and two of roasting. The +black tin is burned by a hot fire in a furnace similar to an oven[21]; +it is burned if it is a dark-blue colour, or if pyrites and the stone +from which iron is made are mixed with it, for the dark blue colour if +not burnt, consumes the tin. If pyrites and the other stone are not +volatilised into fumes in a furnace of this kind, the tin which is made +from the tin-stone is impure. The tin-stone is thrown either into the +back part of the furnace, or into one side of it; but in the former case +the wood is placed in front, in the latter case alongside, in such a +manner, however, that neither firebrands nor coals may fall upon the +tin-stone itself or touch it. The fuel is manipulated by a poker made of +wood. The tin-stone is now stirred with a rake with two teeth, and now +again levelled down with a hoe, both of which are made of iron. The very +fine tin-stone requires to be burned less than that of moderate size, +and this again less than that of the largest size. While the tin-stone +is being thus burned, it frequently happens that some of the material +runs together. + +The burned tin-stone should then be washed again on the strake, for in +this way the material which has been run together is carried away by the +water into the cross-trough, where it is gathered up and worked over, +and again washed on the strake. By this method the metal is separated +from that which is devoid of metal. + +[Illustration 350 (Stall Roasting Matte): A--Pits. B--Wood. C--Cakes. +D--Launder.] + +Cakes from pyrites, or _cadmia_, or cupriferous stones, are roasted in +quadrangular pits, of which the front and top are open, and these pits +are generally twelve feet long, eight feet wide, and three feet deep. +The cakes of melted pyrites are usually roasted twice over, and those of +_cadmia_ once. These latter are first rolled in mud moistened with +vinegar, to prevent the fire from consuming too much of the copper with +the bitumen, or sulphur, or orpiment, or realgar. The cakes of pyrites +are first roasted in a slow fire and afterward in a fierce one, and in +both cases, during the whole following night, water is let in, in order +that, if there is in the cakes any alum or vitriol or saltpetre capable +of injuring the metals, although it rarely does injure them, the water +may remove it and make the cakes soft. The solidified juices are nearly +all harmful to the metal, when cakes or ore of this kind are smelted. +The cakes which are to be roasted are placed on wood piled up in the +form of a crate, and this pile is fired[22]. + +[Illustration 351 (Matte Roasting): A--Cakes. B--Bundles of faggots. +C--Furnaces.] + +The cakes which are made of copper smelted from schist are first thrown +upon the ground and broken, and then placed in the furnace on bundles of +faggots, and these are lighted. These cakes are generally roasted seven +times and occasionally nine times. While this is being done, if they are +bituminous, then the bitumen burns and can be smelled. These furnaces +have a structure like the structure of the furnaces in which ore is +smelted, except that they are open in front; they are six feet high and +four feet wide. As for this kind of furnace, three of them are required +for one of those in which the cakes are melted. First of all they are +roasted in the first furnace, then when they are cooled, they are +transferred into the second furnace and again roasted; later they are +carried to the third, and afterward back to the first, and this order is +preserved until they have been roasted seven or nine times. + + END OF BOOK VIII. + + +FOOTNOTES: + +[1] As would be expected, practically all the technical terms used by +Agricola in this chapter are adaptations. The Latin terms, _canalis_, +_area_, _lacus_, _vasa_, _cribrum_, and _fossa_, have had to be pressed +into service for many different devices, largely by extemporised +combinations. Where the devices described have become obsolete, we have +adopted the nomenclature of the old works on Cornish methods. The +following examples may be of interest:-- + + Simple buddle = _Canalis simplex_ + Divided buddle = _Canalis tabellis distinctus_ + Ordinary strake = _Canalis devexus_ + Short strake = _Area curta_ + Canvas strake = _Area linteis extensis contecta_ + Limp = _Radius_. + +The strake (or streke) when applied to alluvial tin, would have been +termed a "tye" in some parts of Cornwall, and the "short strake" a +"gounce." In the case of the stamp mill, inasmuch as almost every +mechanical part has its counterpart in a modern mill, we have considered +the reader will have less difficulty if the modern designations are used +instead of the old Cornish. The following are the essential terms in +modern, old Cornish, and Latin:-- + + Stamp Stamper _Pilum_ + Stamp-stem Lifter _Pilum_ + Shoes Stamp-heads _Capita_ + Mortar-box Box _Capsa_ + Cam-shaft Barrell _Axis_ + Cams Caps _Dentes_ + Tappets Tongues _Pili dentes_ + Screen Crate _Laminae foraminum plenae_ + Settling pit Catchers _Lacus_ + Jigging sieve Dilleugher _Cribrum angustum_ + + +[2] Agricola uses four Latin verbs in connection with heat operations at +temperatures under the melting point: _Calefacio_, _uro_, _torreo_, and +_cremo_. The first he always uses in the sense of "to warm" or "to +heat," but the last three he uses indiscriminately in much the same way +as the English verbs burn, roast, and calcine are used; but in general +he uses the Latin verbs in the order given to indicate degrees of heat. +We have used the English verbs in their technical sense as indicated by +the context. + +It is very difficult to say when roasting began as a distinct and +separate metallurgical step in sulphide ore treatment. The Greeks and +Romans worked both lead and copper sulphides (see note on p. 391, and +note on p. 403), but neither in the remains of old works nor in their +literature is there anything from which satisfactory details of such a +step can be obtained. The Ancients, of course, understood lime-burning, +and calcined several salts to purify them or to render them more +caustic. Practically the only specific mention is by Pliny regarding +lead ores (see p. 391). Even the statement of Theophilus (1050-1100, +A.D.), may refer simply to rendering ore more fragile, for he says (p. +305) in regard to copper ore: "This stone dug up in abundance is placed +upon a pile and burned (_comburitur_) after the manner of lime. Nor does +it change colour, but loses its hardness and can be broken up, and +afterward it is smelted." The _Probierbüchlein_ casually mentions +roasting prior to assaying, and Biringuccio (III, 2) mentions +incidentally that "dry and ill-disposed ores before everything must be +roasted in an open oven so that the air can get in." He gives no further +information; and therefore this account of Agricola's becomes +practically the first. Apparently roasting, as a preliminary to the +treatment of copper sulphides, did not come into use in England until +some time later than Agricola, for in Col. Grant Francis' "Smelting of +Copper in the Swansea District" (London, 1881, p. 29), a report is set +of the "Doeinges of Jochim Ganse"--an imported German--at the "Mynes by +Keswicke in Cumberland, A.D., 1581," wherein the delinquencies of the +then current practice are described: "Thei never coulde, nether yet can +make (copper) under XXII. tymes passinge thro the fire, and XXII. weekes +doeing thereof ane sometyme more. But now the nature of these IX. +hurtfull humors abovesaid being discovered and opened by Jochim's way of +doeing, we can, by his order of workeinge, so correct theim, that parte +of theim beinge by nature hurtfull to the copper in wasteinge of it, ar +by arte maide freindes, and be not onely an encrease to the copper, but +further it in smeltinge; and the rest of the other evill humors shalbe +so corrected, and their humors so taken from them, that by once +rosteinge and once smeltinge the ure (which shalbe done in the space of +three dayes), the same copper ure shall yeeld us black copper." Jochim +proposed by 'rostynge' to be rid of "sulphur, arsineque, and antimony." + +[3] _Orpiment_ and _realgar_ are the red and yellow arsenical sulphides. +(See note on p. 111). + +[4] _Cadmia bituminosa_. The description of this substance by Agricola, +given below, indicates that it was his term for the complex +copper-zinc-arsenic-cobalt minerals found in the well-known, highly +bituminous, copper schists at Mannsfeld. The later Mineralogists, +Wallerius (_Mineralogia_, Stockholm, 1747), Valmont De Bomare +(_Mineralogie_, Paris, 1762), and others assume Agricola's _cadmia +bituminosa_ to be "black arsenic" or "arsenic noir," but we see no +reason for this assumption. Agricola's statement (_De Nat. Foss._, p. +369) is "... the schistose stone dug up at the foot of the Melibocus +Mountains, or as they are now called the Harz (_Hercynium_), near +Eisleben, Mannsfeld, and near Hettstedt, is similar to _spinos_ (a +bituminous substance described by Theophrastus), if not identical with +it. This is black, bituminous, and cupriferous, and when first extracted +from the mine it is thrown out into an open space and heaped up in a +mound. Then the lower part of the mound is surrounded by faggots, on to +which are likewise thrown stones of the same kind. Then the faggots are +kindled and the fire soon spreads to the stones placed upon them; by +these the fire is communicated to the next, which thus spreads to the +whole heap. This easy reception of fire is a characteristic which +bitumen possesses in common with sulphur. Yet the small, pure and black +bituminous ore is distinguished from the stones as follows: when they +burn they emit the kind of odour which is usually given off by burning +bituminous coal, and besides, if while they are burning a small shower +of rain should fall, they burn more brightly and soften more quickly. +Indeed, when the wind carries the fumes so that they descend into nearby +standing waters, there can be seen floating in it something like a +bituminous liquid, either black, or brown, or purple, which is +sufficient to indicate that those stones were bituminous. And that genus +of stones has been recently found in the Harz in layers, having +occasionally gold-coloured specks of pyrites adhering to them, +representing various flat sea-fish or pike or perch or birds, and +poultry cocks, and sometimes salamanders." + +[5] _Atramentum sutorium rubrum_. Literally, this would be red vitriol. +The German translation gives _rot kupferwasser_, also red vitriol. We +must confess that we cannot make this substance out, nor can we find it +mentioned in the other works of Agricola. It may be the residue from +leaching roasted pyrites for vitriol, which would be reddish oxide of +iron. + +[6] The statement "elsewhere" does not convey very much more +information. It is (_De Nat. Fos._, p. 253): "When Goslar pyrites and +Eisleben (copper) schists are placed on the pyre and roasted for the +third time, they both exude a certain substance which is of a greenish +colour, dry, rough, and fibrous (_tenue_). This substance, like +asbestos, is not consumed by the fire. The schists exude it more +plentifully than the pyrites." The _Interpretatio_ gives _federwis_, as +the German equivalent of _amiantus_ (asbestos). This term was used for +the feathery alum efflorescence on aluminous slates. + +[7] Bearing in mind that bituminous cadmia contained arsenical-cobalt +minerals, this substance "resembling _pompholyx_" would probably be +arsenic oxide. In _De Natura Fossilium_ (p. 368). Agricola discusses the +_pompholyx_ from _cadmia_ at length and pronounces it to be of +remarkably "corrosive" quality. (See also note on p. 112.) + +[8] HISTORICAL NOTE ON CRUSHING AND CONCENTRATION OF ORES. There can be +no question that the first step in the metallurgy of ores was direct +smelting, and that this antedates human records. The obvious advantages +of reducing the bulk of the material to be smelted by the elimination of +barren portions of the ore, must have appealed to metallurgists at a +very early date. Logically, therefore, we should find the second step in +metallurgy to be concentration in some form. The question of crushing is +so much involved with concentration that we have not endeavoured to keep +them separate. The earliest indication of these processes appears to be +certain inscriptions on monuments of the IV Dynasty (4,000 B.C.?) +depicting gold washing (Wilkinson, The Ancient Egyptians, London, 1874, +II, p. 137). Certain stelae of the XII Dynasty (2,400 B.C.) in the +British Museum (144 Bay 1 and 145 Bay 6) refer to gold washing in the +Sudan, and one of them appears to indicate the working of gold ore as +distinguished from alluvial. The first written description of the +Egyptian methods--and probably that reflecting the most ancient +technology of crushing and concentration--is that of Agatharchides, a +Greek geographer of the second Century B.C. This work is lost, but the +passage in question is quoted by Diodorus Siculus (1st Century B.C.) and +by Photius (died 891 A.D.). We give Booth's translation of Diodorus +(London, 1700, p. 89), slightly amended: "In the confines of Egypt and +the neighbouring countries of Arabia and Ethiopia there is a place full +of rich gold mines, out of which with much cost and pains of many +labourers gold is dug. The soil here is naturally black, but in the body +of the earth run many white veins, shining like white marble, surpassing +in lustre all other bright things. Out of these laborious mines, those +appointed overseers cause the gold to be dug up by the labour of a vast +multitude of people. For the Kings of Egypt condemn to these mines +notorious criminals, captives taken in war, persons sometimes falsely +accused, or against whom the King is incens'd; and not only they +themselves, but sometimes all their kindred and relations together with +them, are sent to work here, both to punish them, and by their labour to +advance the profit and gain of the Kings. There are infinite numbers +upon these accounts thrust down into these mines, all bound in fetters, +where they work continually, without being admitted any rest night or +day, and so strictly guarded that there is no possibility or way left to +make an escape. For they set over them barbarians, soldiers of various +and strange languages, so that it is not possible to corrupt any of the +guard by discoursing one with another, or by the gaining insinuations of +familiar converse. The earth which is hardest and full of gold they +soften by putting fire under it, and then work it out with their hands. +The rocks thus soften'd and made more pliant and yielding, several +thousands of profligate wretches break in pieces with hammers and +pickaxes. There is one artist that is the overseer of the whole work, +who marks out the stone, and shows the labourers the way and manner how +he would have it done. Those that are the strongest amongst them that +are appointed to this slavery, provided with sharp iron pickaxes, cleave +the marble-shining rock by mere force and strength, and not by arts or +sleight-of-hand. They undermine not the rock in a direct line, but +follow the bright shining vein of the mine. They carry lamps fastened to +their foreheads to give them light, being otherwise in perfect darkness +in the various windings and turnings wrought in the mine; and having +their bodies appearing sometimes of one colour and sometimes of another +(according to the nature of the mine where they work) they throw the +lumps and pieces of the stone cut out of the rock upon the floor. And +thus they are employed continually without intermission, at the very nod +of the overseer, who lashes them severely besides. And there are little +boys who penetrate through the galleries into the cavities and with +great labour and toil gather up the lumps and pieces hewed out of the +rock as they are cast upon the ground, and carry them forth and lay them +upon the bank. Those that are over thirty years of age take a piece of +the rock of such a certain quantity, and pound it in a stone mortar with +iron pestles till it be as small as a vetch; then those little stones so +pounded are taken from them by women and older men, who cast them into +mills that stand together there near at hand in a long row, and two or +three of them being employed at one mill they grind a certain measure +given to them at a time, until it is as small as fine meal. No care at +all is taken of the bodies of these poor creatures, so that they have +not a rag so much as to cover their nakedness, and no man that sees them +can choose but commiserate their sad and deplorable condition. For +though they are sick, maimed, or lame, no rest nor intermission in the +least is allowed them; neither the weakness of old age, nor women's +infirmities are any plea to excuse them; but all are driven to their +work with blows and cudgelling, till at length, overborne with the +intolerable weight of their misery, they drop down dead in the midst of +their insufferable labours; so that these miserable creatures always +expect the future to be more terrible than even the present, and +therefore long for death as far more desirable than life. + +"At length the masters of the work take the stone thus ground to powder, +and carry it away in order to perfect it. They spread the mineral so +ground upon a broad board, somewhat sloping, and pouring water upon it, +rub it and cleanse it; and so all the earthy and drossy part being +separated from the rest by the water, it runs off the board, and the +gold by reason of its weight remains behind. Then washing it several +times again, they first rub it lightly with their hands; afterward they +draw off any earthy and drossy matter with slender sponges gently +applied to the powdered dust, till it be clean, pure gold. At last other +workmen take it away by weight and measure, and these put it into +earthen pots, and according to the quantity of the gold in every pot +they mix with it some lead, grains of salt, a little tin and barley +bran. Then, covering every pot close, and carefully daubing them over +with clay, they put them in a furnace, where they abide five days and +nights together; then after a convenient time that they have stood to +cool, nothing of the other matter is to be found in the pots but only +pure, refined gold, some little thing diminished in the weight. And thus +gold is prepared in the borders of Egypt, and perfected and completed +with so many and so great toils and vexations. And, therefore, I cannot +but conclude that nature itself teaches us, that as gold is got with +labour and toil, so it is kept with difficulty; it creates everywhere +the greatest cares; and the use of it is mixed both with pleasure and +sorrow." + +The remains at Mt. Laurion show many of the ancient mills and +concentration works of the Greeks, but we cannot be absolutely certain +at what period in the history of these mines crushing and concentration +were introduced. While the mines were worked with great activity prior +to 500 B.C. (see note 6, p. 27), it was quite feasible for the ancient +miner to have smelted these argentiferous lead ores direct. However, at +some period prior to the decadence of the mines in the 3rd Century B.C., +there was in use an extensive system of milling and concentration. For +the following details we are indebted mostly to Edouard Ardaillon (_Les +Mines Du Laurion dans l'Antiquité_, Chap. IV.). The ore was first +hand-picked (in 1869 one portion of these rejects was estimated at +7,000,000 tons) and afterward it was apparently crushed in stone mortars +some 16 to 24 inches in diameter, and thence passed to the mills. These +mills, which crushed dry, were of the upper and lower millstone order, +like the old-fashioned flour mills, and were turned by hand. The stones +were capable of adjustment in such a way as to yield different sizes. +The sand was sifted and the oversize returned to the mills. From the +mills it was taken to washing plants, which consisted essentially of an +inclined area, below which a canal, sometimes with riffles, led through +a series of basins, ultimately returning the water again to near the +head of the area. These washing areas, constructed with great care, were +made of stone cemented over smoothly, and were so efficiently done as to +remain still intact. In washing, a workman brushed upward the pulp +placed on the inclined upper portion of the area, thus concentrating +there a considerable proportion of the galena; what escaped had an +opportunity to settle in the sequence of basins, somewhat on the order +of the buddle. A quotation by Strabo (III, 2, 10) from the lost work of +Polybius (200-125 B.C.) also indicates concentration of lead-silver ores +in Spain previous to the Christian era: "Polybius speaking of the silver +mines of New Carthage, tells us that they are extremely large, distant +from the city about 20 stadia, and occupy a circuit of 400 stadia, that +there are 40,000 men regularly engaged in them, and that they yield +daily to the Roman people (a revenue of) 25,000 drachmae. The rest of +the process I pass over, as it is too long, but as for the silver ore +collected, he tells us that it is broken up, and sifted through sieves +over water; that what remains is to be again broken, and the water +having been strained off, it is to be sifted and broken a third time. +The dregs which remain after the fifth time are to be melted, and the +lead being poured off, the silver is obtained pure. These silver mines +still exist; however, they are no longer the property of the state, +neither these nor those elsewhere, but are possessed by private +individuals. The gold mines, on the contrary, nearly all belong to the +state. Both at Castlon and other places there are singular lead mines +worked. They contain a small proportion of silver, but not sufficient to +pay for the expense of refining." (Hamilton's Translation, Vol. I., p. +222). While Pliny gives considerable information on vein mining and on +alluvial washing, the following obscure passage (XXXIII, 21) appears to +be the only reference to concentration of ores: "That which is dug out +is crushed, washed, roasted, and ground to powder. This powder is called +_apitascudes_, while the silver (lead?) which becomes disengaged in the +furnace is called _sudor_ (sweat). That which is ejected from the +chimney is called _scoria_ as with other metals. In the case of gold +this _scoria_ is crushed and melted again." It is evident enough from +these quotations that the Ancients by "washing" and "sifting," grasped +the practical effect of differences in specific gravity of the various +components of an ore. Such processes are barely mentioned by other +mediæval authors, such as Theophilus, Biringuccio, etc., and thus the +account in this chapter is the first tangible technical description. +Lead mining has been in active progress in Derbyshire since the 13th +century, and concentration was done on an inclined board until the 16th +century, when William Humphrey (see below) introduced the jigging sieve. +Some further notes on this industry will be found in note 1, p. 77. +However, the buddle and strake which appear at that time, are but modest +improvements over the board described by Agatharchides in the quotation +above. + +The ancient crushing appliances, as indicated by the ancient authors and +by the Greek and Roman remains scattered over Europe, were hand-mortars +and mill-stones of the same order as those with which they ground flour. +The stamp-mill, the next advance over grinding in mill-stones, seems to +have been invented some time late in the 15th or early in the 16th +centuries, but who invented it is unknown. Beckmann (Hist. of +Inventions, II, p. 335) says: "In the year 1519 the process of sifting +and wet-stamping was established at Joachimsthal by Paul Grommestetter, +a native of Schwarz, named on that account the Schwarzer, whom Melzer +praises as an ingenious and active washer; and we are told that he had +before introduced the same improvements at Schneeberg. Soon after, that +is in 1521, a large stamping-work was erected at Joachimsthal, and the +process of washing was begun. A considerable saving was thus made, as a +great many metallic particles were before left in the washed sand, which +was either thrown away or used as mortar for building. In the year 1525, +Hans Pörtner employed at Schlackenwalde the wet method of stamping, +whereas before that period the ore there was ground. In the Harz this +invention was introduced at Wildenmann by Peter Philip, who was +assay-master there soon after the works at the Upper Harz were resumed +by Duke Henry the Younger, about the year 1524. This we learn from the +papers of Herdan Hacke or Haecke, who was preacher at Wildenmann in +1572." + +In view of the great amount of direct and indirect reference to tin +mining in Cornwall, covering four centuries prior to Agricola, it would +be natural to expect some statement bearing upon the treatment of ore. +Curiously enough, while alluvial washing and smelting of the black-tin +are often referred to, there is nothing that we have been able to find, +prior to Richard Carew's "Survey of Cornwall" (London, 1602, p. 12) +which gives any tangible evidence on the technical phases of +ore-dressing. In any event, an inspection of charters, tax-rolls, +Stannary Court proceedings, etc., prior to that date gives the +impression that vein mining was a very minor portion of the source of +production. Although Carew's work dates 45 years after Agricola, his +description is of interest: "As much almost dooth it exceede credite, +that the Tynne, for and in so small quantitie digged up with so great +toyle, and passing afterwards thorow the managing of so many hands, ere +it comes to sale, should be any way able to acquite the cost: for being +once brought above ground in the stone, it is first broken in peeces +with hammers; and then carryed, either in waynes, or on horses' backs, +to a stamping mill, where three, and in some places sixe great logges of +timber, bounde at the ends with yron, and lifted up and downe by a +wheele, driven with the water, doe break it smaller. If the stones be +over-moyst, they are dried by the fire in an yron cradle or grate. From +the stamping mill, it passeth to the crazing mill, which betweene two +grinding stones, turned also with a water-wheel, bruseth the same to a +find sand; howbeit, of late times they mostly use wet stampers, and so +have no need of the crazing mills for their best stuffe, but only for +the crust of their tayles. The streame, after it hath forsaken the mill, +is made to fall by certayne degrees, one somewhat distant from another; +upon each of which, at every discent, lyeth a greene turfe, three or +foure foote square, and one foote thick. On this the Tinner layeth a +certayne portion of the sandie Tinne, and with his shovel softly tosseth +the same to and fro, that, through this stirring, the water which +runneth over it may wash away the light earth from the Tinne, which of a +heavier substance lyeth fast on the turfe. Having so clensed one +portion, he setteth the same aside, and beginneth with another, until +his labour take end with his taske. The best of those turfes (for all +sorts serve not) are fetched about two miles to the eastwards of S. +Michael's Mount, where at low water they cast aside the sand, and dig +them up; they are full of rootes of trees, and on some of them nuts have +been found, which confirmeth my former assertion of the sea's intrusion. +After it is thus washed, they put the remnant into a wooden dish, broad, +flat, and round, being about two foote over, and having two handles +fastened at the sides, by which they softly shogge the same to and fro +in the water betweene their legges, as they sit over it, untill +whatsoever of the earthie substance that was yet left be flitted away. +Some of later time, with a sleighter invention, and lighter labour, doe +cause certayne boyes to stir it up and down with their feete, which +worketh the same effect; the residue, after this often clensing, they +call Blacke Tynne." + +It will be noticed that the "wet stampers" and the buddle--worked with +"boyes feete"--are "innovations of late times." And the interesting +question arises as to whether Cornwall did not derive the stamp-mill, +buddle, and strake, from the Germans. The first adequate detailed +description of Cornish appliances is that of Pryce (_Mineralogia +Cornubiensis_, London, 1778) where the apparatus is identical with that +described by Agricola 130 years before. The word "stamper" of Cornwall +is of German origin, from _stampfer_, or, as it is often written in old +German works, _stamper_. However, the pursuit of the subject through +etymology ends here, for no derivatives in German can be found for +buddle, tye, strake, or other collateral terms. The first tangible +evidence of German influence is to be found in Carew who, continuing +after the above quotation, states: "But sithence I gathered stickes to +the building of this poore nest, Sir Francis Godolphin (whose kind helpe +hath much advanced this my playing labour) entertained a Dutch Mynerall +man, and taking light from his experience, but building thereon farre +more profitable conclusions of his owne invention, hath practised a more +saving way in these matters, and besides, made Tynne with good profit of +that refuse which Tynners rejected as nothing worth." Beyond this +quotation we can find no direct evidence of the influence of "Dutch +Mynerall men" in Cornish tin mining at this time. There can be no doubt, +however, that in copper mining in Cornwall and elsewhere in England, the +"Dutch Mynerall men" did play a large part in the latter part of the +16th Century. Pettus (_Fodinæ Regales_, London, 1670, p. 20) states that +"about the third year of Queen Elizabeth (1561) she by the advice of her +Council sent over for some Germans experienced in mines, and being +supplied, she, on the tenth of October, in the sixth of her reign, +granted the mines of eight counties ... to Houghsetter, a German whose +name and family still continue in Cardiganshire." Elizabeth granted +large mining rights to various Germans, and the opening paragraphs of +two out of several Charters may be quoted in point. This grant is dated +1565, and in part reads: "ELIZABETH, by the Grace of God, Queen of +England, France, and Ireland, Defender of the Faith, &c. To all Men to +whom these Letters Patents shall come, Greeting. Where heretofore we +have granted Privileges to Cornelius de Voz, for the Mining and Digging +in our Realm of England, for Allom and Copperas, and for divers Ewers of +Metals that were to be found in digging for the said Allom and Copperas, +incidently and consequently without fraud or guile, as by the same our +Privilege may appear. And where we also moved, by credible Report to us +made, of one Daniel Houghsetter, a German born, and of his Skill and +Knowledge of and in all manner of Mines, of Metals and Minerals, have +given and granted Privilege to Thomas Thurland, Clerk, one of our +Chaplains, and Master of the Hospital of Savoy, and to the same Daniel, +for digging and mining for all manner of Ewers of Gold, Silver, Copper, +and Quicksilver, within our Counties of York, Lancaster, Cumberland, +Westmorland, Cornwall, Devon, Gloucester, and Worcester, and within our +Principality of Wales; and with the same further to deal, as by our said +Privilege thereof granted and made to the said Thomas Thurland and +Daniel Houghsetter may appear. _And_ we now being minded that the said +Commodities, and all other Treasures of the Earth, in all other Places +of our Realm of England...." On the same date another grant reads: +"ELIZABETH, by the Grace of God, Queen of England, France, and Ireland, +Defender of the Faith, &c. To all Men to whom these our Letters Patents +shall come, Greeting. Where we have received credible Information that +our faithful and well-beloved Subject William Humfrey, Saymaster of our +Mint within our Tower of London, by his great Endeavour, Labour, and +Charge, hath brought into this our Realm of England one Christopher +Shutz, an Almain, born at _St. Annen Berg_, under the Obedience of the +Electer of Saxony; a Workman as it is reported, of great Cunning, +Knowledge, and Experience, as well in the finding of the Calamin Stone, +call'd in Latin, _lapis calaminaris_, and in the right and proper use +and commodity thereof, for the Composition of the mix'd Metal commonly +call'd _latten_, etc." Col. Grant-Francis, in his most valuable +collection (Smelting of Copper in the Swansea District, London, 1881) +has published a collection of correspondence relating to early mining +and smelting operations in Great Britain. And among them (p. 1., etc.) +are letters in the years 1583-6 from William Carnsewe and others to +Thomas Smyth, with regard to the first smelter erected at Neath, which +was based upon copper mines in Cornwall. He mentions "Mr. Weston's (a +partner) provydence in bringynge hys Dutch myners hether to aplye such +businys in this countrye ys more to be commendyd than his ignorance of +our countrymen's actyvytyes in suche matters." The principal "Dutche +Mineral Master" referred to was one Ulrick Frosse, who had charge of the +mine at Perin Sands in Cornwall, and subsequently of the smelter at +Neath. Further on is given (p. 25) a Report by Jochim Gaunse upon the +Smelting of copper ores at Keswick in Cumberland in 1581, referred to in +note 2, p. 267. The Daniel Hochstetter mentioned in the Charter above, +together with other German and English gentlemen, formed the "Company of +Mines Royal" and among the properties worked were those with which +Gaunse's report is concerned. There is in the Record Office, London +(Exchequer K.R. Com. Derby 611. Eliz.) the record of an interesting +inquisition into Derbyshire methods in which a then recent great +improvement was the jigging sieve, the introduction of which was due to +William Humphrey (mentioned above). It is possible that he learned of it +from the German with whom he was associated. Much more evidence of the +activity of the Germans in English mining at this period can be adduced. + +On the other hand, Cornwall has laid claims to having taught the art of +tin mining and metallurgy to the Germans. Matthew Paris, a Benedictine +monk, by birth an Englishman, who died in 1259, relates (_Historia Major +Angliae_, London, 1571) that a Cornishman who fled to Germany on account +of a murder, first discovered tin there in 1241, and that in consequence +the price of tin fell greatly. This statement is recalled with great +persistence by many writers on Cornwall. (Camden, _Britannia_, London, +1586; Borlase, Natural History of Cornwall, Oxford, 1758; Pryce, +_Mineralogia Cornubiensis_, London, 1778, p. 70, and others). + +[11] _Lapidibus liquescentibus_. (See note 15, p. 380). + +[12] HISTORICAL NOTE ON AMALGAMATION. The recovery of gold by the use of +mercury possibly dates from Roman times, but the application of the +process to silver does not seem to go back prior to the 16th Century. +Quicksilver was well-known to the Greeks, and is described by +Theophrastus (105) and others (see note 58, p. 432, on quicksilver). +However, the Greeks made no mention of its use for amalgamation, and, in +fact, Dioscorides (V, 70) says "it is kept in vessels of glass, lead, +tin or silver; if kept in vessels of any other kind it consumes them and +flows away." It was used by them for medicinal purposes. The Romans +amalgamated gold with mercury, but whether they took advantage of the +principle to recover gold from ores we do not know. Vitruvius (VII, 8) +makes the following statement:--"If quicksilver be placed in a vessel +and a stone of a hundred pounds' weight be placed on it, it will swim at +the top, and will, notwithstanding its weight, be incapable of pressing +the liquid so as to break or separate it. If this be taken out, and only +a single scruple of gold be put in, that will not swim, but immediately +descend to the bottom. This is a proof that the gravity of a body does +not depend on its weight, but on its nature. Quicksilver is used for +many purposes; without it, neither silver nor brass can be properly +gilt. When gold is embroidered on a garment which is worn out and no +longer fit for use, the cloth is burnt over the fire in earthen pots; +the ashes are thrown into water and quicksilver added to them; this +collects all the particles of gold and unites with them. The water is +then poured off and the residuum placed in a cloth, which, when squeezed +with the hands, suffers the liquid quicksilver to pass through the pores +of the cloth, but retains the gold in a mass within it." (Gwilt's +Trans., p. 217). Pliny is rather more explicit (XXXIII, 32): "All floats +on it (quicksilver) except gold. This it draws into itself, and on that +account is the best means of purifying; for, on being repeatedly +agitated in earthen pots it casts out the other things and the +impurities. These things being rejected, in order that it may give up +the gold, it is squeezed in prepared skins, through which, exuding like +perspiration, it leaves the gold pure." It may be noted particularly +that both these authors state that gold is the only substance that does +not float, and, moreover, nowhere do we find any reference to silver +combining with mercury, although Beckmann (Hist. of Inventions, Vol. I, +p. 14) not only states that the above passage from Pliny refers to +silver, but in further error, attributes the origin of silver +amalgamation of ores to the Spaniards in the Indies. + +The Alchemists of the Middle Ages were well aware that silver would +amalgamate with mercury. There is, however, difficulty in any conclusion +that it was applied by them to separating silver or gold from ore. The +involved gibberish in which most of their utterances was couched, +obscures most of their reactions in any event. The School of Geber +(Appendix B) held that all metals were a compound of "spiritual" mercury +and sulphur, and they clearly amalgamated silver with mercury, and +separated them by distillation. The _Probierbüchlein_ (1520?) describes +a method of recovering silver from the cement used in parting gold and +silver, by mixing the cement (silver chlorides) with quicksilver. +Agricola nowhere in this work mentions the treatment of silver ores by +amalgamation, although he was familiar with Biringuccio (_De La +Pirotechnia_), as he himself mentions in the Preface. This work, +published at least ten years before _De Re Metallica_, contains the +first comprehensive account of silver amalgamation. There is more than +usual interest in the description, because, not only did it precede _De +Re Metallica_, but it is also a specific explanation of the fundamental +essentials of the Patio Process long before the date when the Spaniards +could possibly have invented that process in Mexico. We quote Mr. A. +Dick's translation from Percy (Metallurgy of Silver and Gold, p. 560): + +"He was certainly endowed with much useful and ingenious thought who +invented the short method of extracting metal from the sweepings +produced by those arts which have to do with gold and silver, every +substance left in the refuse by smelters, and also the substance from +certain ores themselves, without the labour of fusing, but by the sole +means and virtue of mercury. To effect this, a large basin is first +constructed of stone or timber and walled, into which is fitted a +millstone made to turn like that of a mill. Into the hollow of this +basin is placed matter containing gold (_della materia vra che tiene +oro_), well ground in a mortar and afterward washed and dried; and, with +the above-mentioned millstone, it is ground while being moistened with +vinegar, or water, in which has been dissolved corrosive sublimate +(_solimato_), verdigris (_verde rame_), and common salt. Over these +materials is then put as much mercury as will cover them; they are then +stirred for an hour or two, by turning the millstone, either by hand, or +horse-power, according to the plan adopted, bearing in mind that the +more the mercury and the materials are bruised together by the +millstone, the more the mercury may be trusted to have taken up the +substance which the materials contain. The mercury, in this condition, +can then be separated from the earthy matter by a sieve, or by washing, +and thus you will recover the auriferous mercury (_el vro mercurio_). +After this, by driving off the mercury by means of a flask (_i.e._, by +heating in a retort or an alembic), or by passing it through a bag, +there will remain, at the bottom, the gold, silver, or copper, or +whatever metal was placed in the basin under the millstone to be ground. +Having been desirous of knowing this secret, I gave to him who taught it +to me a ring with a diamond worth 25 ducats; he also required me to give +him the eighth part of any profit I might make by using it. This I +wished to tell you, not that you should return the ducats to me for +teaching you the secret, but in order that you should esteem it all the +more and hold it dear." + +In another part of the treatise Biringuccio states that washed +(concentrated) ores may be ultimately reduced either by lead or mercury. +Concerning these silver concentrates he writes: "Afterward drenching +them with vinegar in which has been put green copper (_i.e._, +verdigris); or drenching them with water in which has been dissolved +vitriol and green copper...." He next describes how this material should +be ground with mercury. The question as to who was the inventor of +silver amalgamation will probably never be cleared up. According to +Ulloa (_Relacion Historica Del Viage a la America Meridional_, Madrid, +1748) Dom Pedro Fernandes De Velasco discovered the process in Mexico in +1566. The earliest technical account is that of Father Joseph De Acosta +(_Historia Natural y Moral de las Indias_, Seville, 1590, English trans. +Edward Grimston, London, 1604, re-published by the Hakluyt Society, +1880). Acosta was born in 1540, and spent the years 1570 to 1585 in +Peru, and 1586 in Mexico. It may be noted that Potosi was discovered in +1545. He states that refining silver with mercury was introduced at +Potosi by Pedro Fernandes de Velasco from Mexico in 1571, and states +(Grimston's Trans., Vol. I, p. 219): "... They put the powder of the +metall into the vessels upon furnaces, whereas they anoint it and +mortifie it with brine, putting to every fiftie quintalles of powder +five quintalles of salt. And this they do for that the salt separates +the earth and filth, to the end the quicksilver may the more easily draw +the silver unto it. After, they put quicksilver into a piece of holland +and presse it out upon the metall, which goes forth like a dewe, alwaies +turning and stirring the metall, to the end it may be well incorporate. +Before the invention of these furnaces of fire, they did often mingle +their metall with quicksilver in great troughes, letting it settle some +daies, and did then mix it and stirre it againe, until they thought all +the quicksilver were well incorporate with the silver, the which +continued twentie daies and more, and at least nine daies." Frequent +mention of the different methods of silver amalgamation is made by the +Spanish writers subsequent to this time, the best account being that of +Alonso Barba, a priest. Barba was a native of Lepe, in Andalusia, and +followed his calling at various places in Peru from about 1600 to about +1630, and at one time held the Curacy of St. Bernard at Potosi. In 1640 +he published at Madrid his _Arte de los Metales_, etc., in five books. +The first two books of this work were translated into English by the +Earl of Sandwich, and published in London in 1674, under the title "The +First Book of the Art of Metals." This translation is equally wretched +with those in French and German, as might be expected from the +translators' total lack of technical understanding. Among the methods of +silver amalgamation described by Barba is one which, upon later +"discovery" at Virginia City, is now known as the "Washoe Process." None +of the Spanish writers, so far as we know, make reference to +Biringuccio's account, and the question arises whether the Patio Process +was an importation from Europe or whether it was re-invented in Mexico. +While there is no direct evidence on the point, the presumption is in +favour of the former. + +The general introduction of the amalgamation of silver ores into Central +Europe seems to have been very slow, and over 200 years elapsed after +its adoption in Peru and Mexico before it received serious attention by +the German Metallurgists. Ignaz Elder v. Born was the first to establish +the process effectually in Europe, he having in 1784 erected a +"quick-mill" at Glasshutte, near Shemnitz. He published an elaborate +account of a process which he claimed as his own, under the title _Ueber +das Anquicken der Gold und Silberhältigen Erze_, Vienna, 1786. The only +thing new in his process seems to have been mechanical agitation. +According to Born, a Spaniard named Don Juan de Corduba, in the year +1588, applied to the Court at Vienna offering to extract silver from +ores with mercury. Various tests were carried out under the celebrated +Lazarus Erckern, and although it appears that some vitriol and salt were +used, the trials apparently failed, for Erckern concluded his report +with the advice: "That their Lordships should not suffer any more +expense to be thrown away upon this experiment." Born's work was +translated into English by R. E. Raspe, under the title--"Baron Inigo +Born's New Process of Amalgamation, etc.," London, 1791. Some interest +attaches to Raspe, in that he was not only the author of "Baron +Munchausen," but was also the villain in Scott's "Antiquary." Raspe was +a German Professor at Cassel, who fled to England to avoid arrest for +theft. He worked at various mines in Cornwall, and in 1791 involved Sir +John Sinclair in a fruitless mine, but disappeared before that was +known. The incident was finally used by Sir Walter Scott in this novel. + +[13] _Aurum in ea remanet purum_. This same error of assuming squeezed +amalgam to be pure gold occurs in Pliny; see previous footnote. + +[14] George, Duke of Saxony, surnamed "The Bearded," was born 1471, and +died 1539. He was chiefly known for his bitter opposition to the +Reformation. + +[15] The Julian Alps are a section east of the Carnic Alps and lie north +of Trieste. The term Rhaetian Alps is applied to that section along the +Swiss Italian Boundary, about north of Lake Como. + +[16] Ancient Lusitania comprised Portugal and some neighbouring portions +of Spain. + +[17] Colchis, the traditional land of the Golden Fleece, lay between the +Caucasus on the north, Armenia on the south, and the Black Sea on the +west. If Agricola's account of the metallurgical purpose of the fleece +is correct, then Jason must have had real cause for complaint as to the +tangible results of his expedition. The fact that we hear nothing of the +fleece after the day it was taken from the dragon would thus support +Agricola's theory. Tons of ink have been expended during the past thirty +centuries in explanations of what the fleece really was. These +explanations range through the supernatural and metallurgical, but more +recent writers have endeavoured to construct the journey of the +Argonauts into an epic of the development of the Greek trade in gold +with the Euxine. We will not attempt to traverse them from a +metallurgical point of view further than to maintain that Agricola's +explanation is as probable and equally as ingenious as any other, +although Strabo (XI, 2, 19.) gives much the same view long before. + +Alluvial mining--gold washing--being as old as the first glimmer of +civilization, it is referred to, directly or indirectly, by a great +majority of ancient writers, poets, historians, geographers, and +naturalists. Early Egyptian inscriptions often refer to this industry, +but from the point of view of technical methods the description by Pliny +is practically the only one of interest, and in Pliny's chapter on the +subject, alluvial is badly confused with vein mining. This passage +(XXXIII, 21) is as follows: "Gold is found in the world in three ways, +to say nothing of that found in India by the ants, and in Scythia by the +Griffins. The first is as gold dust found in streams, as, for instance, +in the Tagus in Spain, in the Padus in Italy, in the Hebrus in Thracia, +in the Pactolus in Asia, and in the Ganges in India; indeed, there is no +gold found more perfect than this, as the current polishes it thoroughly +by attrition.... Others by equal labour and greater expense bring rivers +from the mountain heights, often a hundred miles, for the purpose of +washing this debris. The ditches thus made are called _corrugi_, from +our word _corrivatio_, I suppose; and these entail a thousand fresh +labours. The fall must be steep, that the water may rush down from very +high places, rather than flow gently. The ditches across the valleys are +joined by aqueducts, and in other places, impassable rocks have to be +cut away and forced to make room for troughs of hollowed-out logs. Those +who cut the rocks are suspended by ropes, so that to those who watch +them from a distance, the workmen seem not so much beasts as birds. +Hanging thus, they take the levels and trace the lines which the ditch +is to take; and thus, where there is no place for man's footstep, +streams are dragged by men. The water is vitiated for washing if the +current of the stream carries mud with it. This kind of earth is called +_urium_, hence these ditches are laid out to carry the water over beds +of pebbles to avoid this _urium_. When they have reached the head of the +fall, at the top of the mountain, reservoirs are excavated a couple of +hundred feet long and wide, and about ten feet deep. In these reservoirs +there are generally five gates left, about three feet square, so that +when the reservoir is full, the gates are opened, and the torrent bursts +forth with such violence that the rocks are hurled along. When they have +reached the plain there is yet more labour. Trenches called _agogae_ are +dug for the flow of the water. The bottoms of these are spread at +regular intervals with _ulex_ to catch the gold. This _ulex_ is similar +to rosemary, rough and prickly. The sides, too, are closed in with +planks and are suspended when crossing precipitous spots. The earth is +carried to the sea and thus the shattered mountain is washed away and +scattered; and this deposition of the earth in the sea has extended the +shore of Spain.... The gold procured from _arrugiae_ does not require to +be melted, but is already pure gold. It is found in lumps, in shafts as +well, sometimes even exceeding ten _librae_ in weight. These lumps are +called _palagae_ and _palacurnae_, while the small grains are called +_baluce_. The Ulex is dried and burnt and the ashes are washed on a bed +of grassy turf in order that the gold may settle thereon." + +[19] _Carbunculus Carchedonius_--Carthaginian carbuncle. The German is +given by Agricola in the _Interpretatio_ as _granat_, _i.e._, garnet. + +[20] As the concentration of crushed tin ore has been exhaustively +treated of already, the descriptions from here on probably refer +entirely to alluvial tin. + +[21] From a metallurgical point of view all of these operations are +roasting. Even to-day, however, the expression "burning" tin is in use +in some parts of Cornwall, and in former times it was general. + +[22] There can be no doubt that these are mattes, as will develop in +Book IX. The German term in the Glossary for _panes ex pyrite_ is +_stein_, the same as the modern German for matte. Orpiment and realgar +are the yellow and red arsenical sulphides. The _cadmia_ was no doubt +the cobalt-arsenic minerals (see note on p. 112). The "solidified +juices" were generally anything that could be expelled short of +smelting, _i.e._, roasted off or leached out, as shown in note 4, p. 1; +they embrace the sulphates, salts, sulphur, bitumen, and arsenical +sulphides, etc. For further information on leaching out the sulphates, +alum, etc., see note 10, p. 564. + + + + +BOOK IX.[1] + + +Since I have written of the varied work of preparing the ores, I will +now write of the various methods of smelting them. Although those who +burn, roast and calcine[2] the ore, take from it something which is +mixed or combined with the metals; and those who crush it with stamps +take away much; and those who wash, screen and sort it, take away still +more; yet they cannot remove all which conceals the metal from the eye +and renders it crude and unformed. Wherefore smelting is necessary, for +by this means earths, solidified juices, and stones are separated from +the metals so that they obtain their proper colour and become pure, and +may be of great use to mankind in many ways. When the ore is smelted, +those things which were mixed with the metal before it was melted are +driven forth, because the metal is perfected by fire in this manner. +Since metalliferous ores differ greatly amongst themselves, first as to +the metals which they contain, then as to the quantity of the metal +which is in them, and then by the fact that some are rapidly melted by +fire and others slowly, there are, therefore, many methods of smelting. +Constant practice has taught the smelters by which of these methods +they can obtain the most metal from any one ore. Moreover, while +sometimes there are many methods of smelting the same ore, by which an +equal weight of metal is melted out, yet one is done at a greater cost +and labour than the others. Ore is either melted with a furnace or +without one; if smelted with a furnace the tap-hole is either +temporarily closed or always open, and if smelted without a furnace, it +is done either in pots or in trenches. But in order to make this matter +clearer, I will describe each in detail, beginning with the buildings +and the furnaces. + +A wall which will be called the "second wall" is constructed of brick +or stone, two feet and as many palms thick, in order that it may be +strong enough to bear the weight. It is built fifteen feet high, and its +length depends on the number of furnaces which are put in the works; +there are usually six furnaces, rarely more, and often less. There are +three furnace walls, a back one which is against the "second" wall, and +two side ones, of which I will speak later. These should be made of +natural stone, as this is more serviceable than burnt bricks, because +bricks soon become defective and crumble away, when the smelter or his +deputy chips off the accretions which adhere to the walls when the ore +is smelted. Natural stone resists injury by the fire and lasts a long +time, especially that which is soft and devoid of cracks; but, on the +contrary, that which is hard and has many cracks is burst asunder by the +fire and destroyed. For this reason, furnaces which are made of the +latter are easily weakened by the fire, and when the accretions are +chipped off they crumble to pieces. The front furnace wall should be +made of brick, and there should be in the lower part a mouth three palms +wide and one and a half feet high, when the hearth is completed. A hole +slanting upward, three palms long, is made through the back furnace +wall, at the height of a cubit, before the hearth has been prepared; +through this hole and a hole one foot long in the "second" wall--as the +back of this wall has an arch--is inserted a pipe of iron or bronze, in +which are fixed the nozzles of the bellows. The whole of the front +furnace wall is not more than five feet high, so that the ore may be +conveniently put into the furnace, together with those things which the +master needs for his work of smelting. Both the side walls of the +furnace are six feet high, and the back one seven feet, and they are +three palms thick. The interior of the furnace is five palms wide, six +palms and a digit long, the width being measured by the space which lies +between the two side walls, and the length by the space between the +front and the back walls; however, the upper part of the furnace widens +out somewhat. + +[Illustration 357 (Blast Furnaces): A--Furnaces. B--Forehearths.] + +There are two doors in the second wall if there are six furnaces, one of +the doors being between the second and third furnaces and the other +between the fourth and fifth furnaces. They are a cubit wide and six +feet high, in order that the smelters may not have mishaps in coming and +going. It is necessary to have a door to the right of the first furnace, +and similarly one to the left of the last, whether the wall is longer or +not. The second wall is carried further when the rooms for the +cupellation furnaces, or any other building, adjoin the rooms for the +blast furnaces, these buildings being only divided by a partition. The +smelter, and the ones who attend to the first and the last furnaces, if +they wish to look at the bellows or to do anything else, go out through +the doors at the end of the wall, and the other people go through the +other doors, which are the common ones. The furnaces are placed at a +distance of six feet from one another, in order that the smelters and +their assistants may more easily sustain the fierceness of the heat. +Inasmuch as the interior of each furnace is five palms wide and each is +six feet distant from the other, and inasmuch as there is a space of +four feet three palms at the right side of the first furnace and as much +at the left side of the last furnace, and there are to be six furnaces +in one building, then it is necessary to make the second wall fifty-two +feet long; because the total of the widths of all of the furnaces is +seven and a half feet, the total of the spaces between the furnaces is +thirty feet, the space on the outer sides of the first and last furnaces +is nine feet and two palms, and the thickness of the two transverse +walls is five feet, which make a total measurement of fifty-two feet.[3] + +Outside each furnace hearth there is a small pit full of powder which is +compressed by ramming, and in this manner is made the forehearth which +receives the metal flowing from the furnaces. Of this I will speak +later. + +[Illustration 358 (Blast Furnaces): A--Furnaces. B--Forehearth. C--Door. +D--Water tank. E--Stone which covers it. F--Material of the vent walls. +G--Stone which covers it. H--Pipe exhaling the vapour.] + +Buried about a cubit under the forehearth and the hearth of the furnace +is a transverse water-tank, three feet long, three palms wide and a +cubit deep. It is made of stone or brick, with a stone cover, for if it +were not covered, the heat would draw the moisture from below and the +vapour might be blown into the hearth of the furnace as well as into the +forehearth, and would dampen the blast. The moisture would vitiate the +blast, and part of the metal would be absorbed and part would be mixed +with the slags, and in this manner the melting would be greatly damaged. +From each water-tank is built a walled vent, to the same depth as the +tank, but six digits wide; this vent slopes upward, and sooner or +later penetrates through to the other side of the wall, against which +the furnace is built. At the end of this vent there is an opening where +the steam, into which the water has been converted, is exhausted through +a copper or iron tube or pipe. This method of making the tank and the +vent is much the best. Another kind has a similar vent but a different +tank, for it does not lie transversely under the forehearth, but +lengthwise; it is two feet and a palm long, and a foot and three palms +wide, and a foot and a palm deep. This method of making tanks is not +condemned by us, as is the construction of those tanks without a vent; +the latter, which have no opening into the air through which the vapour +may discharge freely, are indeed to be condemned. + +[Illustration 359 (Bellows for blast furnaces)] + +Fifteen feet behind the second wall is constructed the first wall, +thirteen feet high. In both of these are fixed roof beams[4], which are +a foot wide and thick, and nineteen feet and a palm long; these are +placed three feet distant from one another. As the second wall is two +feet higher than the first wall, recesses are cut in the back of it two +feet high, one foot wide, and a palm deep, and in these recesses, as it +were in mortises, are placed one end of each of the beams. Into these +ends are mortised the bottoms of just as many posts; these posts are +twenty-four feet high, three palms wide and thick, and from the tops of +the posts the same number of rafters stretch downward to the ends of the +beams superimposed on the first wall; the upper ends of the rafters are +mortised into the posts and the lower ends are mortised into the ends of +the beams laid on the first wall; the rafters support the roof, which +consists of burnt tiles. Each separate rafter is propped up by a +separate timber, which is a cross-beam, and is joined to its post. +Planks close together are affixed to the posts above the furnaces; these +planks are about two digits thick and a palm wide, and they, together +with the wicker work interposed between the timbers, are covered with +lute so that there may be no risk of fire to the timbers and +wicker-work. In this practical manner is constructed the back part of +the works, which contains the bellows, their frames, the mechanism for +compressing the bellows, and the instrument for distending them, of all +of which I will speak hereafter. + +[Illustration 361 (Plan of Smelter Building): The four long walls: +A--First. B--Second. C--Third. D--Fourth. The seven transverse walls: +E--First. F--Second. G--Third. H--Fourth. I--Fifth. K--Sixth. +L--Seventh, or middle.] + +In front of the furnaces is constructed the third long wall and likewise +the fourth. Both are nine feet high, but of the same length and +thickness as the other two, the fourth being nine feet distant from the +third; the third is twenty-one and a half feet from the second. At a +distance of twelve feet from the second wall, four posts seven and a +half feet high, a cubit wide and thick, are set upon rock laid +underneath. Into the tops of the posts the roof beam is mortised; this +roof beam is two feet and as many palms longer than the distance between +the second and the fifth transverse walls, in order that its ends may +rest on the transverse walls. If there should not be so long a beam at +hand, two are substituted for it. As the length of the long beam is as +above, and as the posts are equidistant, it is necessary that the posts +should be a distance of nine feet, one palm, two and two-fifths digits +from each other, and the end ones this distance from the transverse +walls. On this longitudinal beam and to the third and fourth walls are +fixed twelve secondary beams twenty-four feet long, one foot wide, three +palms thick, and distant from each other three feet, one palm, and two +digits. In these secondary beams, where they rest on the longitudinal +beams, are mortised the ends of the same number of rafters as there are +posts which stand on the second wall. The ends of the rafters do not +reach to the tops of the posts, but are two feet away from them, that +through this opening, which is like the open part of a forge, the +furnaces can emit their fumes. In order that the rafters should not fall +down, they are supported partly by iron rods, which extend from each +rafter to the opposite post, and partly supported by a few tie-beams, +which in the same manner extend from some rafters to the posts opposite, +and give them stability. To these tie-beams, as well as to the rafters +which face the posts, a number of boards, about two digits thick and a +palm wide, are fixed at a distance of a palm from each other, and are +covered with lute so that they do not catch fire. In the secondary +beams, where they are laid on the fourth wall, are mortised the lower +ends of the same number of rafters as those in a set of rafters[5] +opposite them. From the third long wall these rafters are joined and +tied to the ends of the opposite rafters, so that they may not slip, and +besides they are strengthened with substructures which are made of cross +and oblique timbers. The rafters support the roof. + +In this manner the front part of the building is made, and is divided +into three parts; the first part is twelve feet wide and is under the +hood, which consists of two walls, one vertical and one inclined. The +second part is the same number of feet wide and is for the reception of +the ore to be smelted, the fluxes, the charcoal, and other things which +are needed by the smelter. The third part is nine feet wide and contains +two separate rooms of equal size, in one of which is the assay furnace, +while the other contains the metal to be melted in the cupellation +furnaces. It is thus necessary that in the building there should be, +besides the four long walls, seven transverse walls, of which the first +is constructed from the upper end of the first long wall to the upper +end of the second long wall; the second proceeds from the end of this to +the end of the third long wall; the third likewise from this end of the +last extends to the end of the fourth long wall; the fourth leads from +the lower end of the first long wall to the lower end of the second long +wall; the fifth extends from the end of this to the end of the third +long wall; the sixth extends from this last end to the end of the fourth +long wall; the seventh divides into two parts the space between the +third and fourth long walls. + +To return to the back part of the building, in which, as I said, are the +bellows[6], their frames, the machinery for compressing them, and the +instrument for distending them. Each bellows consists of a body and a +head. The body is composed of two "boards," two bows, and two hides. The +upper board is a palm thick, five feet and three palms long, and two and +a half feet wide at the back part, where each of the sides is a little +curved, and it is a cubit wide at the front part near the head. The +whole of the body of the bellows tapers toward the head. That which we +now call the "board" consists of two pieces of pine, joined and glued +together, and of two strips of linden wood which bind the edges of the +board, these being seven digits wide at the back, and in front near the +head of the bellows one and a half digits wide. These strips are glued +to the boards, so that there shall be less damage from the iron nails +driven through the hide. There are some people who do not surround the +boards with strips, but use boards only, which are very thick. The upper +board has an aperture and a handle; the aperture is in the middle of the +board and is one foot three palms distant from where the board joins the +head of the bellows, and is six digits long and four wide. The lid for +this aperture is two palms and a digit long and wide, and three digits +thick; toward the back of the lid is a little notch cut into the surface +so that it may be caught by the hand; a groove is cut out of the top of +the front and sides, so that it may engage in mouldings a palm wide and +three digits thick, which are also cut out in a similar manner under the +edges. Now, when the lid is drawn forward the hole is closed, and when +drawn back it is opened; the smelter opens the aperture a little so that +the air may escape from the bellows through it, if he fears the hides +might be burst when the bellows are too vigorously and quickly inflated; +he, however, closes the aperture if the hides are ruptured and the air +escapes. Others perforate the upper board with two or three round holes +in the same place as the rectangular one, and they insert plugs in them +which they draw out when it is necessary. The wooden handle is seven +palms long, or even longer, in order that it may extend outside; +one-half of this handle, two palms wide and one thick, is glued to the +end of the board and fastened with pegs covered with glue; the other +half projects beyond the board, and is rounded and seven digits thick. +Besides this, to the handle and to the board is fixed a cleat two feet +long, as many palms wide and one palm thick, and to the under side of +the same board, at a distance of three palms from the end, is fixed +another cleat two feet long, in order that the board may sustain the +force of distension and compression; these two cleats are glued to the +board, and are fastened to it with pegs covered with glue. + +The lower bellows-board, like the upper, is made of two pieces of pine +and of two strips of linden wood, all glued together; it is of the same +width and thickness as the upper board, but is a cubit longer, this +extension being part of the head of which I have more to say a little +later. This lower bellows-board has an air-hole and an iron ring. The +air-hole is about a cubit distant from the posterior end, and it is +midway between the sides of the bellows-board, and is a foot long and +three palms wide; it is divided into equal parts by a small rib which +forms part of the board, and is not cut from it; this rib is a palm long +and one-third of a digit wide. The flap of the air-hole is a foot and +three digits long, three palms and as many digits wide; it is a thin +board covered with goat skin, the hairy part of which is turned toward +the ground. There is fixed to one end of the flap, with small iron +nails, one-half of a doubled piece of leather a palm wide and as long as +the flap is wide; the other half of the leather, which is behind the +flap, is twice perforated, as is also the bellows-board, and these +perforations are seven digits apart. Passing through these a string is +tied on the under side of the board; and thus the flap when tied to the +board does not fall away. In this manner are made the flap and the +air-hole, so when the bellows are distended the flap opens, when +compressed it closes. At a distance of about a foot beyond the air-hole +a slightly elliptical iron ring, two palms long and one wide, is +fastened by means of an iron staple to the under part of the +bellows-board; it is at a distance of three palms from the back of the +bellows. In order that the lower bellows-board may remain stationary, a +wooden bolt is driven into the ring, after it penetrates through the +hole in the transverse supporting plank which forms part of the frame +for the bellows. There are some who dispense with the ring and fasten +the bellows-board to the frame with two iron screws something like +nails. + +The bows are placed between the two boards and are of the same length as +the upper board. They are both made of four pieces of linden wood three +digits thick, of which the two long ones are seven digits wide at the +back and two and a half at the front; the third piece, which is at the +back, is two palms wide. The ends of the bows are a little more than a +digit thick, and are mortised to the long pieces, and both having been +bored through, wooden pegs covered with glue are fixed in the holes; +they are thus joined and glued to the long pieces. Each of the ends is +bowed (_arcuatur_) to meet the end of the long part of the bow, whence +its name "bow" originated. The fourth piece keeps the ends of the bow +distended, and is placed a cubit distant from the head of the bellows; +the ends of this piece are mortised into the ends of the bow and are +joined and glued to them; its length without the tenons is a foot, and +its width a palm and two digits. There are, besides, two other very +small pieces glued to the head of the bellows and to the lower board, +and fastened to them by wooden pegs covered with glue, and they are +three palms and two digits long, one palm high, and a digit thick, one +half being slightly cut away. These pieces keep the ends of the bow away +from the hole in the bellows-head, for if they were not there, the ends, +forced inward by the great and frequent movement, would be broken. + +The leather is of ox-hide or horse-hide, but that of the ox is far +preferable to that of the horse. Each of these hides, for there are two, +is three and a half feet wide where they are joined at the back part of +the bellows. A long leathern thong is laid along each of the +bellows-boards and each of the bows, and fastened by T-shaped iron nails +five digits long; each of the horns of the nails is two and a half +digits long and half a digit wide. The hide is attached to the +bellows-boards by means of these nails, so that a horn of one nail +almost touches the horn of the next; but it is different with the bows, +for the hide is fastened to the back piece of the bow by only two nails, +and to the two long pieces by four nails. In this practical manner they +put ten nails in one bow and the same number in the other. Sometimes +when the smelter is afraid that the vigorous motion of the bellows may +pull or tear the hide from the bows, he also fastens it with little +strips of pine by means of another kind of nail, but these strips cannot +be fastened to the back pieces of the bow, because these are somewhat +bent. Some people do not fix the hide to the bellows-boards and bows by +iron nails, but by iron screws, screwed at the same time through strips +laid over the hide. This method of fastening the hide is less used than +the other, although there is no doubt that it surpasses it in +excellence. + +Lastly, the head of the bellows, like the rest of the body, consists of +two boards, and of a nozzle besides. The upper board is one cubit long, +one and a half palms thick. The lower board is part of the whole of the +lower bellows-board; it is of the same length as the upper piece, but a +palm and a digit thick. From these two glued together is made the head, +into which, when it has been perforated, the nozzle is fixed. The back +part of the head, where it is attached to the rest of the bellows-body, +is a cubit wide, but three palms forward it becomes two digits narrower. +Afterward it is somewhat cut away so that the front end may be rounded, +until it is two palms and as many digits in diameter, at which point it +is bound with an iron ring three digits wide. + +The nozzle is a pipe made of a thin plate of iron; the diameter in front +is three digits, while at the back, where it is encased in the head of +the bellows, it is a palm high and two palms wide. It thus gradually +widens out, especially at the back, in order that a copious wind can +penetrate into it; the whole nozzle is three feet long. + +[Illustration 365 (Bellows for blast furnaces): A--Upper bellows-board. +B--Lower bellows-board. C--The two pieces of wood of which each +consists. D--Posterior arched part of each. E--Tapered front part of +each. F--Pieces of linden wood. G--Aperture in the upper board. H--Lid. +I--Little mouldings of wood. K--Handle. L--Cleat on the outside. The +cleat inside I am not able to depict. M--Interior of the lower +bellows-board. N--Part of the head. O--Air-hole. P--Supporting bar. +Q--Flap. R--Hide. S--Thong. T--Exterior of the lower board. V--Staple. +X--Ring. Y--Bow. Z--Its long pieces. AA--Back piece of the bow. BB--The +bowed ends. CC--Crossbar distending the bow. DD--The two little pieces. +EE--Hide. FF--Nail. GG--Horn of the nail. HH--A screw. II--Long thong. +KK--Head. LL--Its lower board. MM--Its upper board. NN--Nozzle. OO--The +whole of the lower bellows-board. PP--The two exterior plates of the +head hinges. QQ--Their curved piece. RR--Middle plate of the head. +SS--The two outer plates of the upper bellows-board. TT--Its middle +plate. VV--Little axle. XX--Whole bellows.] + +The upper bellows-board is joined to the head of the bellows in the +following way. An iron plate[7], a palm wide and one and a half palms +long, is first fastened to the head at a distance of three digits from +the end; from this plate there projects a piece three digits long and +two wide, curved in a small circle. The other side has a similar plate. +Then in the same part of the upper board are fixed two other iron +plates, distant two digits from the edge, each of which are six digits +wide and seven long; in each of these plates the middle part is cut away +for a little more than three digits in length and for two in depth, so +that the curved part of the plates on the head corresponding to them may +fit into this cut out part. From both sides of each plate there project +pieces, three digits long and two digits wide, similarly curved into +small circles. A little iron pin is passed through these curved pieces +of the plates, like a little axle, so that the upper board of the +bellows may turn upon it. The little axle is six digits long and a +little more than a digit thick, and a small groove is cut out of the +upper board, where the plates are fastened to it, in such a manner that +the little axle when fixed to the plates may not fall out. Both plates +fastened to the bellows-board are affixed by four iron nails, of which +the heads are on the inner part of the board, whereas the points, +clinched at the top, are transformed into heads, so to speak. Each of +the other plates is fastened to the head of the bellows by means of a +nail with a wide head, and by two other nails of which the heads are on +the edge of the bellows-head. Midway between the two plates on the +bellows-board there remains a space two palms wide, which is covered by +an iron plate fastened to the board by little nails; and another plate +corresponding to this is fastened to the head between the other two +plates; they are two palms and the same number of digits wide. + +The hide is common to the head as to all the other parts of the body; +the plates are covered with it, as well as the front part of the upper +bellows-board, and both the bows and the back of the head of the +bellows, so that the wind may not escape from that part of the bellows. +It is three palms and as many digits wide, and long enough to extend +from one of the sides of the lower board over the back of the upper; it +is fastened by many T-headed nails on one side to the upper board, and +on the other side to the head of the bellows, and both ends are fastened +to the lower bellows-board. + +In the above manner the bellows is made. As two are required for each +furnace, it is necessary to have twelve bellows, if there are to be six +furnaces in one works. + +[Illustration 368 (Bellows for blast furnaces): A--Front sill. B--Back +sill. C--Front posts. D--Their slots. E--Beam imposed upon them. +F--Higher posts. G--Their slots. H--Beam imposed upon them. I--Timber +joined in the mortises of the posts. K--Planks. L--Transverse supporting +planks. M--The holes in them. N--Pipe. O--Its front end. P--Its rear +end.] + +Now it is time to describe their framework. First, two sills a little +shorter than the furnace wall are placed on the ground. The front one of +these is three palms wide and thick, and the back one three palms and +two digits. The front one is two feet distant from the back wall of the +furnace, and the back one is six feet three palms distant from the front +one. They are set into the earth, that they may remain firm; there are +some who accomplish this by means of pegs which, through several holes, +penetrate deeply into the ground. + +Then twelve short posts are erected, whose lower ends are mortised into +the sill that is near the back of the furnace wall; these posts are two +feet high, exclusive of the tenons, and are three palms and the same +number of digits wide, and two palms thick. A slot one and a half palms +wide is cut through them, beginning two palms from the bottom and +extending for a height of three palms. All the posts are not placed at +the same intervals, the first being at a distance of three feet five +digits from the second, and likewise the third from the fourth, but the +second is two feet one palm and three digits from the third; the +intervals between the other posts are arranged in the same manner, equal +and unequal, of which each four pertain to two furnaces. The upper ends +of these posts are mortised into a transverse beam which is twelve feet, +two palms, and three digits long, and projects five digits beyond the +first post and to the same distance beyond the fourth; it is two palms +and the same number of digits wide, and two palms thick. Since each +separate transverse beam supports four bellows, it is necessary to have +three of them. + +Behind the twelve short posts the same number of higher posts are +erected, of which each has the middle part of the lower end cut out, so +that its two resulting lower ends are mortised into the back sill; these +posts, exclusive of the tenons, are twelve feet and two palms high, and +are five palms wide and two palms thick. They are cut out from the +bottom upward, the slot being four feet and five digits high and six +digits wide. The upper ends of these posts are mortised into a long beam +imposed upon them; this long beam is placed close under the timbers +which extend from the wall at the back of the furnace to the first long +wall; the beam is three palms wide and two palms thick, and forty-three +feet long. If such a long one is not at hand, two or three may be +substituted for it, which when joined together make up that length. +These higher posts are not placed at equal distances, but the first is +at a distance of two feet three palms one digit from the second, and the +third is at the same distance from the fourth; while the second is at a +distance of one foot three palms and the same number of digits from the +third, and in the same manner the rest of the posts are arranged at +equal and unequal intervals. Moreover, there is in every post, where it +faces the shorter post, a mortise at a foot and a digit above the slot; +in these mortises of the four posts is tenoned a timber which itself has +four mortises. Tenons are enclosed in mortises in order that they may be +better joined, and they are transfixed with wooden pins. This timber is +thirteen feet three palms one digit long, and it projects beyond the +first post a distance of two palms and two digits, and to the same +number of palms and digits beyond the fourth post. It is two palms and +as many digits wide, and also two palms thick. As there are twelve posts +it is necessary to have three timbers of this kind. + +On each of these timbers, and on each of the cross-beams which are laid +upon the shorter posts, are placed four planks, each nine feet long, two +palms three digits wide, and two palms one digit thick. The first plank +is five feet one palm one digit distant from the second, at the front as +well as at the back, for each separate plank is placed outside of the +posts. The third is at the same distance from the fourth, but the second +is one foot and three digits distant from the third. In the same manner +the rest of the eight planks are arranged at intervals, the fifth from +the sixth and the seventh from the eighth are at the same distances as +the first from the second and the third from the fourth; the sixth is at +the same distance from the seventh as the second from the third. + +Two planks support one transverse plank six feet long, one foot wide, +one palm thick, placed at a distance of three feet and two palms from +the back posts. When there are six of these supporting planks, on each +separate one are placed two bellows; the lower bellows-boards project a +palm beyond them. From each of the bellows-boards an iron ring descends +through a hole in its supporting plank, and a wooden peg is driven into +the ring, so that the bellows-board may remain stationary, as I stated +above. + +The two bellows communicate, each by its own plank, to the back of a +copper pipe in which are set both of the nozzles, and their ends are +tightly fastened in it. The pipe is made of a rolled copper or iron +plate, a foot and two palms and the same number of digits long; the +plate is half a digit thick, but a digit thick at the back. The interior +of the pipe is three digits wide, and two and a half digits high in the +front, for it is not absolutely round; and at the back it is a foot and +two palms and three digits in diameter. The plate from which the pipe is +made is not entirely joined up, but at the front there is left a crack +half a digit wide, increasing at the back to three digits. This pipe is +placed in the hole in the furnace, which, as I said, was in the middle +of the wall and the arch. The nozzles of the bellows, placed in this +pipe, are a distance of five digits from its front end. + +[Illustration 370 (Bellows for blast furnaces): A--Lever which when +depressed by means of a cam compresses the bellows. B--Slots through the +posts. C--Bar. D--Iron implement with a rectangular link. E--Iron +instrument with round ring. F--Handle of bellows. G--Upper post. +H--Upper lever. I--Box with equal sides. K--Box narrow at the bottom. +L--Pegs driven into the upper lever.] + +The levers are of the same number as the bellows, and when depressed by +the cams of the long axle they compress the bellows. These levers are +eight feet three palms long, one palm wide and thick, and the ends are +inserted in the slots of the posts; they project beyond the front posts +to a distance of two palms, and the same distance beyond the back posts +in order that each may have its end depressed by its two cams on the +axle. The cams not only penetrate into the slots of the back posts, but +project three digits beyond them. An iron pin is set in round holes made +through both sides of the slot of each front post, at three palms and as +many digits from the bottom; the pin penetrates the lever, which turns +about it when depressed or raised. The back of the lever for the length +of a cubit is a palm and a digit wider than the rest, and is perforated; +in this hole is engaged a bar six feet and two palms long, three digits +wide, and about one and one-half digits thick; it is somewhat hooked at +the upper end, and approaches the handle of the bellows. Under the lever +there is a nail, which penetrates through a hole in the bar, so that the +lever and bar may move together. The bar is perforated in the upper end +at a distance of six digits from the top; this hole is two palms long +and a digit wide, and in it is engaged the hook of an iron implement +which is a digit thick. At the upper part this implement has either a +round or square opening, like a link, and at the lower end is hooked; +the link is two digits high and wide and the hook is three digits long; +the middle part between the link and the hook is three palms and two +digits long. The link of this implement engages either the handle of the +bellows, or else a large ring which does engage it. This iron ring is a +digit thick, two palms wide on the inside of the upper part, and two +digits in the lower part, and this iron ring, not unlike the first one, +engages the handle of the bellows. The iron ring either has its narrower +part turned upward, and in it is engaged the ring of another iron +implement, similar to the first, whose hook, extending upward, grips the +rope fastened to the iron ring holding the end of the second lever, of +which I will speak presently; or else the iron ring grips this lever, +and then in its hook is engaged the ring of the other implement whose +ring engages the handle of the bellows, and in this case the rope is +dispensed with. + +Resting on beams fixed in the two walls is a longitudinal beam, at a +distance of four and a half feet from the back posts; it is two palms +wide, one and a half palms thick. There are mortised into this +longitudinal beam the lower ends of upper posts three palms wide and two +thick, which are six feet two palms high, exclusive of their tenons. The +upper ends of these posts are mortised into an upper longitudinal beam, +which lies close under the rafters of the building; this upper +longitudinal beam is two palms wide and one thick. The upper posts have +a slot cut out upward from a point two feet from the bottom, and the +slot is two feet high and six digits wide. Through these upper posts a +round hole is bored from one side to the other at a point three feet one +palm from the bottom, and a small iron axle penetrates through the hole +and is fastened there. Around this small iron axle turns the second +lever when it is depressed and raised. This lever is eight feet long, +and its other end is three digits wider than the rest of the lever; at +this widest point is a hole two digits wide and three high, in which is +fixed an iron ring, to which is tied the rope I have mentioned; it is +five palms long, its upper loop is two palms and as many digits wide, +and the lower one is one palm one digit wide. This half of the second +lever, the end of which I have just mentioned, is three palms high and +one wide; it projects three feet beyond the slot of the post on which it +turns; the other end, which faces the back wall of the furnaces, is one +foot and a palm high and a foot wide. + +On this part of the lever stands and is fixed a box three and a half +feet long, one foot and one palm wide, and half a foot deep; but these +measurements vary; sometimes the bottom of this box is narrower, +sometimes equal in width to the top. In either case, it is filled with +stones and earth to make it heavy, but the smelters have to be on their +guard and make provision against the stones falling out, owing to the +constant motion; this is prevented by means of an iron band which is +placed over the top, both ends being wedge-shaped and driven into the +lever so that the stones can be held in. Some people, in place of the +box, drive four or more pegs into the lever and put mud between them, +the required amount being added to the weight or taken away from it. + +There remains to be considered the method of using this machine. The +lower lever, being depressed by the cams, compresses the bellows, and +the compression drives the air through the nozzle. Then the weight of +the box on the other end of the upper lever raises the upper +bellows-board, and the air is drawn in, entering through the air-hole. + +[Illustration 372 (Bellows for blast furnaces): A--Axle. B--Water-wheel. +C--Drum composed of rundles. D--Other axle. E--Toothed wheel. F--Its +spokes. G--Its segments. H--Its teeth. I--Cams of the axle.] + +The machine whose cams depress the lower lever is made as follows. First +there is an axle, on whose end outside the building is a water-wheel; at +the other end, which is inside the building, is a drum made of rundles. +This drum is composed of two double hubs, a foot apart, which are five +digits thick, the radius all round being a foot and two digits; but they +are double, because each hub is composed of two discs, equally thick, +fastened together with wooden pegs glued in. These hubs are sometimes +covered above and around by iron plates. The rundles are thirty in +number, a foot and two palms and the same number of digits long, with +each end fastened into a hub; they are rounded, three digits in +diameter, and the same number of digits apart. In this practical manner +is made the drum composed of rundles. + +There is a toothed wheel, two palms and a digit thick, on the end of +another axle; this wheel is composed of a double disc[8]. The inner disc +is composed of four segments a palm thick, everywhere two palms and a +digit wide. The outer disc, like the inner, is made of four segments, +and is a palm and a digit thick; it is not equally wide, but where the +head of the spokes are inserted it is a foot and a palm and digit wide, +while on each side of the spokes it becomes a little narrower, until the +narrowest part is only two palms and the same number of digits wide. The +outer segments are joined to the inner ones in such a manner that, on +the one hand, an outer segment ends in the middle of an inner one, and, +on the other hand, the ends of the inner segments are joined in the +middle of the outer ones; there is no doubt that by this kind of joining +the wheel is made stronger. The outer segments are fastened to the inner +by means of a large number of wooden pegs. Each segment, measured over +its round back, is four feet and three palms long. There are four +spokes, each two palms wide and a palm and a digit thick; their length, +excluding the tenons, being two feet and three digits. One end of the +spoke is mortised into the axle, where it is firmly fastened with pegs; +the wide part of the other end, in the shape of a triangle, is mortised +into the outer segment opposite it, keeping the shape of the same as far +as the segment ascends. They also are joined together with wooden pegs +glued in, and these pegs are driven into the spokes under the inner +disc. The parts of the spokes in the shape of the triangle are on the +inside; the outer part is simple. This triangle has two sides equal, the +erect ones as is evident, which are a palm long; the lower side is not +of the same length, but is five digits long, and a mortise of the same +shape is cut out of the segments. The wheel has sixty teeth, since it is +necessary that the rundle drum should revolve twice while the toothed +wheel revolves once. The teeth are a foot long, and project one palm +from the inner disc of the wheel, and three digits from the outer disc; +they are a palm wide and two and a half digits thick, and it is +necessary that they should be three digits apart, as were the rundles. + +The axle should have a thickness in proportion to the spokes and the +segments. As it has two cams to depress each of the levers, it is +necessary that it should have twenty-four cams, which project beyond it +a foot and a palm and a digit. The cams are of almost semicircular +shape, of which the widest part is three palms and a digit wide, and +they are a palm thick; they are distributed according to the four sides +of the axle, on the upper, the lower and the two lateral sides. The axle +has twelve holes, of which the first penetrates through from the upper +side to the lower, the second from one lateral side to the other; the +first hole is four feet two palms distant from the second; each +alternate one of these holes is made in the same direction, and they are +arranged at equal intervals. Each single cam must be opposite another; +the first is inserted into the upper part of the first hole, the second +into the lower part of the same hole, and so fixed by pegs that they do +not fall out; the third cam is inserted into that part of the second +hole which is on the right side, and the fourth into that part on the +left. In like manner all the cams are inserted into the consecutive +holes, for which reason it happens that the cams depress the levers of +the bellows in rotation. Finally we must not omit to state that this is +only one of many such axles having cams and a water-wheel. + +I have arrived thus far with many words, and yet it is not unreasonable +that I have in this place pursued the subject minutely, since the +smelting of all the metals, to which I am about to proceed, could not be +undertaken without it. + +The ores of gold, silver, copper, and lead, are smelted in a furnace by +four different methods. The first method is for the rich ores of gold or +silver, the second for the mediocre ores, the third for the poor ores, +and the fourth method is for those ores which contain copper or lead, +whether they contain precious metals or are wanting in them. The +smelting of the first ores is performed in the furnace of which the +tap-hole is intermittently closed; the other three ores are melted in +furnaces of which the tap-holes are always open. + +[Illustration 373 (Stamp-mill): A--Charcoal. B--Mortar-box. C--Stamps.] + +First, I will speak of the manner in which the furnaces are prepared for +the smelting of the ores, and of the first method of smelting. The +powder from which the hearth and forehearth should be made is composed +of charcoal and earth (clay?). The charcoal is crushed by the stamps in +a mortar-box, the front of which is closed by a board at the top, while +the charcoal, crushed to powder, is removed through the open part +below; the stamps are not shod with iron, but are made entirely of wood, +although at the lower part they are bound round at the wide part by an +iron band. + +[Illustration 374 (Clay Washing): A--Tub. B--Sieve. C--Rods. +D--Bench-frame.] + +The powder into which the charcoal is crushed is thrown on to a sieve +whose bottom consists of interwoven withes of wood. The sieve is drawn +backward and forward over two wooden or iron rods placed in a triangular +position on a tub, or over a bench-frame set on the floor of the +building; the powder which falls into the tub or on to the floor is of +suitable size, but the pieces of small charcoal which remain in the +sieve are emptied out and thrown back under the stamps. + +[Illustration 375 (Clay Washing): A--Screen. B--Poles. C--Shovel. +D--Two-wheeled cart. E--Hand-sieve. F--Narrow boards. G--Box. H--Covered +pit.] + +When the earth is dug up it is first exposed to the sun that it may dry. +Later on it is thrown with a shovel on to a screen--set up obliquely and +supported by poles,--made of thick, loosely woven hazel withes, and in +this way the fine earth and its small lumps pass through the holes of +the screen, but the clods and stones do not pass through, but run down +to the ground. The earth which passes through the screen is conveyed in +a two-wheeled cart to the works and there sifted. This sieve, which is +not dissimilar to the one described above, is drawn backward and +forward upon narrow boards of equal length placed over a long box; the +powder which falls through the sieve into the box is suitable for the +mixture; the lumps that remain in the sieve are thrown away by some +people, but by others they are placed under the stamps. This powdered +earth is mixed with powdered charcoal, moistened, and thrown into a pit, +and in order that it may remain good for a long time, the pit is covered +up with boards so that the mixture may not become contaminated. + +[Illustration 377 (Implements for Furnace Work): A--Furnace. B--Ladder. +C--Board fixed to it. D--Hoe. E--Five-toothed rake. F--Wooden spatula. +G--Broom. H--Rammer. I--Rammer, same diameter. K--Two wooden spatulas. +L--Curved blade. M--Bronze rammer. N--Another bronze rammer. O--Wide +spatula. P--Rod. Q--Wicker basket. R--Two buckets of leather in which +water is carried for putting out a conflagration, should the _officina_ +catch fire. S--Brass pump with which the water is squirted out. T--Two +hooks. V--Rake. X--Workman beating the clay with an iron implement.] + +They take two parts of pulverised charcoal and one part of powdered +earth, and mix them well together with a rake; the mixture is moistened +by pouring water over it so that it may easily be made into shapes +resembling snowballs; if the powder be light it is moistened with more +water, if heavy with less. The interior of the new furnace is lined with +lute, so that the cracks in the walls, if there are any, may be filled +up, but especially in order to preserve the rock from injury by fire. In +old furnaces in which ore has been melted, as soon as the rocks have +cooled the assistant chips away, with a spatula, the accretions which +adhere to the walls, and then breaks them up with an iron hoe or a rake +with five teeth. The cracks of the furnace are first filled in with +fragments of rock or brick, which he does by passing his hand into the +furnace through its mouth, or else, having placed a ladder against it, +he mounts by the rungs to the upper open part of the furnace. To the +upper part of the ladder a board is fastened that he may lean and +recline against it. Then standing on the same ladder, with a wooden +spatula, he smears the furnace walls over with lute; this spatula is +four feet long, a digit thick, and for a foot upward from the bottom it +is a palm wide, or even wider, generally two and a half digits. He +spreads the lute equally over the inner walls of the furnace. The mouth +of the copper pipe[9] should not protrude from the lute, lest sows[10] +form round about it and thus impede the melting, for the furnace bellows +could not force a blast through them. Then the same assistant throws a +little powdered charcoal into the pit of the forehearth and sprinkles it +with pulverised earth. Afterward, with a bucket he pours water into it +and sweeps this all over the forehearth pit, and with the broom drives +the turbid water into the furnace hearth and likewise sweeps it out. +Next he throws the mixed and moistened powder into the furnace, and then +a second time mounting the steps of the ladder, he introduces the rammer +into the furnace and pounds the powder so that the hearth is made solid. +The rammer is rounded and three palms long; at the bottom it is five +digits in diameter, at the top three and a half, therefore it is made in +the form of a truncated cone; the handle of the rammer is round and five +feet long and two and a half digits thick; the upper part of the +rammer, where the handle is inserted, is bound with an iron band two +digits wide. There are some who, instead, use two rounded rammers three +and a half digits in diameter, the same at the bottom as at the top. +Some people prefer two wooden spatulas, or a rammer spatula. + +In a similar manner, mixed and moistened powder is thrown and pounded +with a rammer in the forehearth pit, which is outside the furnace. When +this is nearly completed, powder is again put in, and pushed with the +rammer up toward the protruding copper pipe, so that from a point a +digit under the mouth of the copper pipe the hearth slopes down into the +crucible of the forehearth,[11] and the metal can run down. The same is +repeated until the forehearth pit is full, then afterward this is +hollowed out with a curved blade; this blade is of iron, two palms and +as many digits long, three digits wide, blunt at the top and sharp at +the bottom. The crucible of the forehearth must be round, a foot in +diameter and two palms deep if it has to contain a _centumpondium_ of +lead, or if only seventy _librae_, then three palms in diameter and two +palms deep like the other. When the forehearth has been hollowed out it +is pounded with a round bronze rammer. This is five digits high and the +same in diameter, having a curved round handle one and a half digits +thick; or else another bronze rammer is used, which is fashioned in the +shape of a cone, truncated at the top, on which is imposed another cut +away at the bottom, so that the middle part of the rammer may be grasped +by the hand; this is six digits high, and five digits in diameter at the +lower end and four at the top. Some use in its place a wooden spatula +two and a half palms wide at the lower end and one palm thick. + +The assistant, having prepared the forehearth, returns to the furnace +and besmears both sides as well as the top of the mouth with simple +lute. In the lower part of the mouth he places lute that has been dipped +in charcoal dust, to guard against the risk of the lute attracting to +itself the powder of the hearth and vitiating it. Next he lays in the +mouth of the furnace a straight round rod three quarters of a foot long +and three digits in diameter. Afterward he places a piece of charcoal on +the lute, of the same length and width as the mouth, so that it is +entirely closed up; if there be not at hand one piece of charcoal so +large, he takes two instead. When the mouth is thus closed up, he throws +into the furnace a wicker basket full of charcoal, and in order that the +piece of charcoal with which the mouth of the furnace is closed should +not then fall out, the master holds it in with his hand. The pieces of +charcoal which are thrown into the furnace should be of medium size, for +if they are large they impede the blast of the bellows and prevent it +from blowing through the tap-hole of the furnace into the forehearth to +heat it. Then the master covers over the charcoal, placed at the mouth +of the furnace, with lute and extracts the wooden rod, and thus the +furnace is prepared. Afterward the assistant throws four or five larger +baskets full of charcoal into the furnace, filling it right up; he also +throws a little charcoal into the forehearth, and places glowing coals +upon it in order that it may be kindled, but in order that the flames of +this fire should not enter through the tap-hole of the furnace and fire +the charcoal inside, he covers the tap-hole with lute or closes it with +fragments of pottery. Some do not warm the forehearth the same evening, +but place large charcoals round the edge of it, one leaning on the +other; those who follow the first method sweep out the forehearth in the +morning, and clean out the little pieces of charcoal and cinders, while +those who follow the latter method take, early in the morning, burning +firebrands, which have been prepared by the watchman of the works, and +place them on the charcoal. + +At the fourth hour the master begins his work. He first inserts a small +piece of glowing coal into the furnace, through the bronze nozzle-pipe +of the bellows, and blows up the fire with the bellows; thus within the +space of half an hour the forehearth, as well as the hearth, becomes +warmed, and of course more quickly if on the preceding day ores have +been smelted in the same furnace, but if not then it warms more slowly. +If the hearth and forehearth are not warmed before the ore to be smelted +is thrown in, the furnace is injured and the metals lost; or if the +powder from which both are made is damp in summer or frozen in winter, +they will be cracked, and, giving out a sound like thunder, they will +blow out the metals and other substances with great peril to the +workmen. After the furnace has been warmed, the master throws in slags, +and these, when melted, flow out through the tap-hole into the +forehearth. Then he closes up the tap-hole at once with mixed lute and +charcoal dust; this plug he fastens with his hand to a round wooden +rammer that is five digits thick, two palms high, with a handle three +feet long. The smelter extracts the slags from the forehearth with a +hooked bar; if the ore to be smelted is rich in gold or silver he puts +into the forehearth a _centumpondium_ of lead, or half as much if the +ore is poor, because the former requires much lead, the latter little; +he immediately throws burning firebrands on to the lead so that it +melts. Afterward he performs everything according to the usual manner +and order, whereby he first throws into the furnace as many cakes melted +from pyrites[12], as he requires to smelt the ore; then he puts in two +wicker baskets full of ore with litharge and hearth-lead[13], and stones +which fuse easily by fire of the second order, all mixed together; then +one wicker basket full of charcoal, and lastly the slags. The furnace +now being filled with all the things I have mentioned, the ore is slowly +smelted; he does not put too much of it against the back wall of the +furnace, lest sows should form around the nozzles of the bellows and the +blast be impeded and the fire burn less fiercely. + +This, indeed, is the custom of many most excellent smelters, who know +how to govern the four elements[14]. They combine in right proportion +the ores, which are part earth, placing no more than is suitable in the +furnaces; they pour in the needful quantity of water; they moderate with +skill the air from the bellows; they throw the ore into that part of the +fire which burns fiercely. The master sprinkles water into each part of +the furnace to dampen the charcoal slightly, so that the minute parts of +ore may adhere to it, which otherwise the blast of the bellows and the +force of the fire would agitate and blow away with the fumes. But as the +nature of the ores to be smelted varies, the smelters have to arrange +the hearth now high, now low, and to place the pipe in which the nozzles +of the bellows are inserted sometimes on a great and sometimes at a +slight angle, so that the blast of the bellows may blow into the +furnace in either a mild or a vigorous manner. For those ores which heat +and fuse easily, a low hearth is necessary for the work of the smelters, +and the pipe must be placed at a gentle angle to produce a mild blast +from the bellows. On the contrary, those ores that heat and fuse slowly +must have a high hearth, and the pipe must be placed at a steep incline +in order to blow a strong blast of the bellows, and it is necessary, for +this kind of ore, to have a very hot furnace in which slags, or cakes +melted from pyrites, or stones which melt easily in the fire[15], are +first melted, so that the ore should not settle in the hearth of the +furnace and obstruct and choke up the tap-hole, as the minute metallic +particles that have been washed from the ores are wont to do. Large +bellows have wide nozzles, for if they were narrow the copious and +strong blast would be too much compressed and too acutely blown into the +furnace, and then the melted material would be chilled, and would form +sows around the nozzle, and thus obstruct the opening into the furnace, +which would cause great damage to the proprietors' property. If the ores +agglomerate and do not fuse, the smelter, mounting on the ladder placed +against the side of the furnace, divides the charge with a pointed or +hooked bar, which he also pushes down into the pipe in which the nozzle +of the bellows is placed, and by a downward movement dislodges the ore +and the sows from around it. + +After a quarter of an hour, when the lead which the assistant has placed +in the forehearth is melted, the master opens the tap-hole of the +furnace with a tapping-bar. This bar is made of iron, is three and a +half feet long, the forward end pointed and a little curved, and the +back end hollow so that into it may be inserted a wooden handle, which +is three feet long and thick enough to be well grasped by the hand. The +slag first flows from the furnace into the forehearth, and in it are +stones mixed with metal or with the metal adhering to them partly +altered, the slag also containing earth and solidified juices. After +this the material from the melted pyrites flows out, and then the molten +lead contained in the forehearth absorbs the gold and silver. When that +which has run out has stood for some time in the forehearth, in order to +be able to separate one from the other, the master first either skims +off the slags with the hooked bar or else lifts them off with an iron +fork; the slags, as they are very light, float on the top. He next draws +off the cakes of melted pyrites, which as they are of medium weight hold +the middle place; he leaves in the forehearth the alloy of gold or +silver with the lead, for these being the heaviest, sink to the bottom. +As, however, there is a difference in slags, the uppermost containing +little metal, the middle more, and the lowest much, he puts these away +separately, each in its own place, in order that to each heap, when it +is re-smelted, he may add the proper fluxes, and can put in as much lead +as is demanded for the metal in the slag; when the slag is re-melted, if +it emits much odour, there is some metal in it; if it emits no odour, +then it contains none. He puts the cakes of melted pyrites away +separately, as they were nearest in the forehearth to the metal, and +contain a little more of it than the slags; from all these cakes a +conical mound is built up, by always placing the widest of them at the +bottom. The hooked bar has a hook on the end, hence its name; otherwise +it is similar to other bars. + +[Illustration 383 (Blast Furnaces): A, B, C--Three furnaces. At the +first stands the smelter, who with a ladle pours the alloy out of the +forehearth into the moulds. D--Forehearth. E--Ladle. F--Moulds. G--Round +wooden rammer. H--Tapping-bar. At the second furnace stands the smelter, +who opens the tap-hole with his tapping-bar. The assistant, standing on +steps placed against the third furnace which has been broken open, chips +off the accretions. I--Steps. K--Spatula. L--The other hooked bar. +M--Mine captain carrying a cake, in which he has stuck the pick, to the +scales to be weighed. N--Another mine captain opens a chest in which his +things are kept.] + +Afterward the master closes up the tap-hole and fills the furnace with +the same materials I described above, and again, the ores having been +melted, he opens the tap-hole, and with a hooked bar extracts the slags +and the cakes melted from pyrites, which have run down into the +forehearth. He repeats the same operation until a certain and definite +part of the ore has been smelted, and the day's work is at an end; if +the ore was rich the work is finished in eight hours; if poor, it takes +a longer time. But if the ore was so rich as to be smelted in less than +eight hours, another operation is in the meanwhile combined with the +first, and both are performed in the space of ten hours. When all the +ore has been smelted, he throws into the furnace a basket full of +litharge or hearth-lead, so that the metal which has remained in the +accretions may run out with these when melted. When he has finally drawn +out of the forehearth the slags and the cakes melted from pyrites, he +takes out, with a ladle, the lead alloyed with gold or silver and pours +it into little iron or copper pans, three palms wide and as many digits +deep, but first lined on the inside with lute and dried by warming, lest +the glowing molten substances should break through. The iron ladle is +two palms wide, and in other respects it is similar to the others, all +of which have a sufficiently long iron shaft, so that the fire should +not burn the wooden part of the handle. When the alloy has been poured +out of the forehearth, the smelter foreman and the mine captain weigh +the cakes. + +Then the master breaks out the whole of the mouth of the furnace with a +crowbar, and with that other hooked bar, the rabble and the five-toothed +rake, he extracts the accretions and the charcoal. This crowbar is not +unlike the other hooked one, but larger and wider; the handle of the +rabble is six feet long and is half of iron and half of wood. The +furnace having cooled, the master chips off the accretions clinging to +the walls with a rectangular spatula six digits long, a palm broad, and +sharp on the front edge; it has a round handle four feet long, half of +it being of iron and half of wood. This is the first method of smelting +ores. + +Because they generally consist of unequal constituents, some of which +melt rapidly and others slowly, the ores rich in gold and silver cannot +be smelted as rapidly or as easily by the other methods as they can by +the first method, for three important reasons. The first reason is that, +as often as the closed tap-hole of the furnace is opened with a +tapping-bar, so often can the smelter observe whether the ore is +melting too quickly or too slowly, or whether it is flaming in scattered +bits, and not uniting in one mass; in the first case the ore is smelting +too slowly and not without great expense; in the second case the metal +mixes with the slag which flows out of the furnace into the forehearth, +wherefore there is the expense of melting it again; in the third case, +the metal is consumed by the violence of the fire. Each of these evils +has its remedy; if the ore melts slowly or does not come together, it is +necessary to add some amount of fluxes which melt the ore; or if they +melt too readily, to decrease the amount. + +The second reason is that each time that the furnace is opened with a +tapping-bar, it flows out into the forehearth, and the smelter is able +to test the alloy of gold and lead or of silver with lead, which is +called _stannum_.[16] When the tap-hole is opened the second or third +time, this test shows us whether the alloy of gold or silver has become +richer, or whether the lead is too debilitated and wanting in strength +to absorb any more gold or silver. If it has become richer, some portion +of lead added to it should renew its strength; if it has not become +richer, it is poured out of the forehearth that it may be replaced with +fresh lead. + +The third reason is that if the tap-hole of the furnace is always open +when the ore and other things are being smelted, the fluxes, which are +easily melted, run out of the furnace before the rich gold and silver +ores, for these are sometimes of a kind that oppose and resist melting +by the fire for a longer period. It follows in this case, that some part +of the ore is either consumed or is mixed with the accretions, and as a +result little lumps of ore not yet melted are now and then found in the +accretions. Therefore when these ores are being smelted, the tap-hole of +the furnace should be closed for a time, as it is necessary to heat and +mix the ore and the fluxes at the same time; since the fluxes fuse more +rapidly than the ore, when the molten fluxes are held in the furnace, +they thus melt the ore which does not readily fuse or mix with the lead. +The lead absorbs the gold or silver, just as tin or lead when melted in +the forehearth absorbs the other unmelted metal which has been thrown +into it. But if the molten matter is poured upon that which is not +molten, it runs off on all sides and consequently does not melt it. It +follows from all this that ores rich in gold or silver, when put into a +furnace with its tap-hole always open, cannot for that reason be smelted +so successfully as in one where the tap-hole is closed for a time, so +that during this time the ore may be melted by the molten fluxes. +Afterward, when the tap-hole has been opened, they flow into the +forehearth and mix there with the molten lead. This method of smelting +the ores is used by us and by the Bohemians. + +[Illustration 385 (Blast Furnaces): A, B--Two furnaces. C--Forehearths. +D--Dipping-pot. The smelter standing by the first furnace draws off the +slags with a hooked bar. E--Hooked bar. F--Slags. G--The assistant +drawing a bucket of water which he pours over the glowing slags to +quench them. H--Basket made of twigs of wood intertwined. I--Rabble. +K--Ore to be smelted. L--The master stands at the other furnace and +prepares the forehearth by ramming it with two rammers. M--Crowbar.] + +The three remaining methods of smelting ores are similar to each other +in that the tap-holes of the furnaces always remain open, so that the +molten metals may continually run out. They differ greatly from each +other, however, for the tap-hole of the first of this kind is deeper +in the furnace and narrower than that of the third, and besides it is +invisible and concealed. It easily discharges into the forehearth, which +is one and a half feet higher than the floor of the building, in order +that below it to the left a dipping-pot can be made. When the forehearth +is nearly full of the slags, which well up from the invisible tap-hole +of the furnace, they are skimmed off from the top with a hooked bar; +then the alloy of gold or silver with lead and the melted pyrites, being +uncovered, flow into the dipping-pot, and the latter are made into +cakes; these cakes are broken and thrown back into the furnace so that +all their metal may be smelted out. The alloy is poured into little iron +moulds. + +The smelter, besides lead and cognate things, uses fluxes which combine +with the ore, of which I gave a sufficient account in Book VII. The +metals which are melted from ores that fuse readily in the fire, are +profitable because they are smelted in a short time, while those which +are difficult to fuse are not as profitable, because they take a long +time. When fluxes remain in the furnace and do not melt, they are not +suitable; for this reason, accretions and slags are the most convenient +for smelting, because they melt quickly. It is necessary to have an +industrious and experienced smelter, who in the first place takes care +not to put into the furnace more ores mixed with fluxes than it can +accommodate. + +The powder out of which this furnace hearth and the adjoining forehearth +and the dipping-pot are usually made, consists mostly of equal +proportions of charcoal dust and of earth, or of equal parts of the same +and of ashes. When the hearth of the furnace is prepared, a rod that +will reach to the forehearth is put into it, higher up if the ore to be +smelted readily fuses, and lower down if it fuses with difficulty. When +the dipping-pot and forehearth are finished, the rod is drawn out of the +furnace so that the tap-hole is open, and through it the molten material +flows continuously into the forehearth, which should be very near the +furnace in order that it may keep very hot and the alloy thus be made +purer. If the ore to be smelted does not melt easily, the hearth of the +furnace must not be made too sloping, lest the molten fluxes should run +down into the forehearth before the ore is smelted, and the metal thus +remain in the accretions on the sides of the furnace. The smelter must +not ram the hearth so much that it becomes too hard, nor make the +mistake of ramming the lower part of the mouth to make it hard, for it +could not breathe[17], nor could the molten matter flow freely out of +the furnace. The ore which does not readily melt is thrown as much as +possible to the back of the furnace, and toward that part where the fire +burns very fiercely, so that it may be smelted longer. In this way the +smelter may direct it whither he wills. Only when it glows at the part +near the bellows' nozzle does it signify that all the ore is smelted +which has been thrown to the side of the furnace in which the nozzles +are placed. If the ore is easily melted, one or two wicker baskets full +are thrown into the front part of the furnace so that the fire, being +driven back by it, may also smelt the ore and the sows that form round +about the nozzles of the bellows. This process of smelting is very +ancient among the Tyrolese[18], but not so old among the Bohemians. + +[Illustration 387 (Blast Furnaces): A, B--Two furnaces. C--Forehearth. +D--Dipping-pots. The master stands at the one furnace and draws away the +slags with an iron fork. E--Iron fork. F--Wooden hoe with which the +cakes of melted pyrites are drawn out. G--The forehearth crucible: +one-half inside is to be seen open in the other furnace. H--The half +outside the furnace. I--The assistant prepares the forehearth, which is +separated from the furnace that it may be seen. K--Bar. L--Wooden +rammer. M--Ladder. N--Ladle.] + +The second method of smelting ores stands in a measure midway between +that one performed in a furnace of which the tap-hole is closed +intermittently, and the first of the methods performed in a furnace +where the tap-hole is always open. In this manner are smelted the ores +of gold and silver that are neither very rich nor very poor, but +mediocre, which fuse easily and are readily absorbed by the lead. It was +found that in this way a large quantity of ore could be smelted at one +operation without much labour or great expense, and could thus be +alloyed with lead. This furnace has two crucibles, one of which is half +inside the furnace and half outside, so that the lead being put into +this crucible, the part of the lead which is in the furnace absorbs the +metals of the ores which easily fuse; the other crucible is lower, and +the alloy and the molten pyrites run into it. Those who make use of this +method of smelting, tap the alloy of gold or silver with lead from the +upper crucible once or twice if need be, and throw in other lead or +litharge, and each absorbs that flux which is nearest. This method of +smelting is in use in Styria[19]. + +[Illustration 389 (Furnaces): A, B--Two furnaces. C--Tap-holes of +furnaces. D--Forehearths. E--Their tap-holes. F--Dipping-pots. G--At the +one furnace stands the smelter carrying a wicker basket full of +charcoal. At the other furnace stands a smelter who with the third +hooked bar breaks away the material which has frozen the tap-hole of the +furnace. H--Hooked bar. I--Heap of charcoal. K--Barrow on which is a box +made of wicker work in which the coals are measured. L--Iron spade.] + +The furnace in the third method of smelting ores has the tap-hole +likewise open, but the furnace is higher and wider than the others, and +its bellows are larger; for these reasons a larger charge of the ore can +be thrown into it. When the mines yield a great abundance of ore for the +smelter, they smelt in the same furnace continuously for three days and +three nights, providing there be no defect either in the hearth or in +the forehearth. In this kind of a furnace almost every kind of accretion +will be found. The forehearth of the furnace is not unlike the +forehearth of the first furnace of all, except that it has a tap-hole. +However, because large charges of ore are smelted uninterruptedly, and +the melted material runs out and the slags are skimmed off, there is +need for a second forehearth crucible, into which the molten material +runs through an opened tap-hole when the first is full. When a smelter +has spent twelve hours' labour on this work, another always takes his +place. The ores of copper and lead and the poorest ores of gold and +silver are smelted by this method, because they cannot be smelted by the +other three methods on account of the greater expense occasioned. Yet by +this method a _centumpondium_ of ore containing only one or two +_drachmae_ of gold, or only a half to one _uncia_, of silver,[20] can be +smelted; because there is a large amount of ore in each charge, smelting +is continuous, and without expensive fluxes such as lead, litharge, and +hearth-lead. In this method of smelting we must use only cupriferous +pyrites which easily melt in the fire, in truth the cakes melted out +from this, if they no longer absorb much gold or silver, are +replenished again from crude pyrites alone. If from this poor ore, with +melted pyrites alone, material for cakes cannot be made, there are added +other fluxes which have not previously been melted. These fluxes are, +namely, lead ore, stones easily fused by fire of the second order and +sand made from them, limestone, _tophus_, white schist, and iron +stone[21]. + +Although this method of smelting ores is rough and might not seem to be +of great use, yet it is clever and useful; for a great weight of ores, +in which the gold, silver, or copper are in small quantities, may be +reduced into a few cakes containing all the metal. If on being first +melted they are too crude to be suitable for the second melting, in +which the lead absorbs the precious metals that are in the cakes, or in +which the copper is melted out of them, yet they can be made suitable if +they are repeatedly roasted, sometimes as often as seven or eight times, +as I have explained in the last book. Smelters of this kind are so +clever and expert, that in smelting they take out all the gold and +silver which the assayer in assaying the ores has stated to be contained +in them, because if during the first operation, when he makes the cakes, +there is a _drachma_ of gold or half an _uncia_ of silver lost from the +ores, the smelter obtains it from the slags by the second smelting. This +method of smelting ores is old and very common to most of those who use +other methods. + +[Illustration 393 (Lead smelting Furnaces): A--Furnace of the Carni. +B--Low wall. C--Wood. D--Ore dripping lead. E--Large crucible. +F--Moulds. G--Ladle. H--Slabs of lead. I--Rectangular hole at the back +of the furnace. K--Saxon furnace. L--Opening in the back of the furnace. +M--Wood. N--Upper crucible. O--Dipping-pot. P--Westphalian method of +melting. Q--Heaps of charcoal. R--Straw. S--Wide slabs. T--Crucibles. +V--Polish hearth.] + +Although lead ores are usually smelted in the third furnace--whose +tap-hole is always open,--yet not a few people melt them in special +furnaces by a method which I will briefly explain. The _Carni_[22] first +burn such lead ores, and afterward break and crush them with large round +mallets. Between the two low walls of a hearth, which is inside a +furnace made of and vaulted with a rock that resists injury by the fire +and does not burn into chalk, they place green wood with a layer of dry +wood on the top of it; then they throw the ore on to this, and when the +wood is kindled the lead drips down and runs on to the underlying +sloping hearth[23]. This hearth is made of pulverised charcoal and +earth, as is also a large crucible, one-half of which lies under the +furnace and the other half outside it, into which runs the lead. The +smelter, having first skimmed off the slags and other things with a hoe, +pours the lead with a ladle into moulds, taking out the cakes after they +have cooled. At the back of the furnace is a rectangular hole, so that +the fire may be allowed more draught, and so that the smelter can crawl +through it into the furnace if necessity demands. + +The Saxons who inhabit Gittelde, when smelting lead ore in a furnace not +unlike a baking oven, put the wood in through a hole at the back of the +furnace, and when it begins to burn vigorously the lead trickles out of +the ore into a forehearth. When this is full, the smelting being +accomplished, the tap-hole is opened with a bar, and in this way the +lead, together with the slags, runs into the dipping-pots below. +Afterward the cakes of lead, when they are cold, are taken from the +moulds. + +In Westphalia they heap up ten wagon-loads of charcoal on some hillside +which adjoins a level place, and the top of the heap being made flat, +straw is thrown upon it to the thickness of three or four digits. On the +top of this is laid as much pure lead ore as the heap can bear; then +the charcoal is kindled, and when the wind blows, it fans the fire so +that the ore is smelted. In this wise the lead, trickling down from the +heap, flows on to the level and forms broad thin slabs. A few hundred +pounds of lead ore are kept at hand, which, if things go well, are +scattered over the heap. These broad slabs are impure and are laid upon +dry wood which in turn is placed on green wood laid over a large +crucible, and the former having been kindled, the lead is re-melted. + +The Poles use a hearth of bricks four feet high, sloping on both sides +and plastered with lute. On the upper level part of the hearth large +pieces of wood are piled, and on these is placed small wood with lute +put in between; over the top are laid wood shavings, and upon these +again pure lead ore covered with large pieces of wood. When these are +kindled, the ore melts and runs down on to the lower layer of wood; +and when this is consumed by the fire, the metal is collected. If +necessity demand, it is melted over and over again in the same manner, +but it is finally melted by means of wood laid over the large crucible, +the slabs of lead being placed upon it. + +The concentrates from washing are smelted together with slags (fluxes?) +in a third furnace, of which the tap-hole is always open. + +[Illustration 395 (Blast Furnaces): A--Furnaces. B--Vaulted roof. +C--Columns. D--Dust-chamber. E--Opening. F--Chimney. G--Window. H--Door. +I--Chute.] + +It is worth while to build vaulted dust-chambers over the furnaces, +especially over those in which the precious ores are to be smelted, in +order that the thicker part of the fumes, in which metals are not +wanting, may be caught and saved. In this way two or more furnaces are +combined under the same vaulted ceiling, which is supported by the wall, +against which the furnaces are built, and by four columns. Under this +the smelters of the ore perform their work. There are two openings +through which the fumes rise from the furnaces into the wide vaulted +chamber, and the wider this is the more fumes it collects; in the middle +of this chamber over the arch is an opening three palms high and two +wide. This catches the fumes of both furnaces, which have risen up from +both sides of the vaulted chamber to its arch, and have fallen again +because they could not force their way out; and they thus pass out +through the opening mentioned, into the chimney which the Greeks call +[Greek: kapnodochê], the name being taken from the object. The chimney +has thin iron plates fastened into the walls, to which the thinner +metallic substances adhere when ascending with the fumes. The thicker +metallic substances, or _cadmia_,[25] adhere to the vaulted chamber, and +often harden into stalactites. On one side of the chamber is a window in +which are set panes of glass, so that the light may be transmitted, but +the fumes kept in; on the other side is a door, which is kept entirely +closed while the ores are being smelted in the furnaces, so that none of +the fumes may escape. It is opened in order that the workman, passing +through it, may be enabled to enter the chamber and remove the soot and +_pompholyx_[26] and chip off the _cadmia_; this sweeping is done twice +a year. The soot mixed with _pompholyx_ and the _cadmia_, being chipped +off, is thrown down through a long chute made of four boards joined in +the shape of a rectangle, that they should not fly away. They fall on to +the floor, and are sprinkled with salt water, and are again smelted with +ore and litharge, and become an emolument to the proprietors. Such +chambers, which catch the metallic substances that rise with the fumes, +are profitable for all metalliferous ores; but especially for the minute +metallic particles collected by washing crushed ores and rock, because +these usually fly out with the fire of the furnaces. + +I have explained the four general methods of smelting ores; now I will +state how the ores of each metal are smelted, or how the metal is +obtained from the ore. I will begin with gold. Its sand, the +concentrates from washing, or the gold dust collected in any other +manner, should very often not be smelted, but should be mixed with +quicksilver and washed with tepid water, so that all the impurities may +be eliminated. This method I explained in Book VII. Or they are placed +in the _aqua_ which separates gold from silver, for this also separates +its impurities. In this method we see the gold sink in the glass +ampulla, and after all the _aqua_ has been drained from the particles, +it frequently remains as a gold-coloured residue at the bottom; this +powder, when it has been moistened with oil made from argol[27], is then +dried and placed in a crucible, where it is melted with borax or with +saltpetre and salt; or the same very fine dust is thrown into molten +silver, which absorbs it, and from this it is again parted by _aqua +valens_[28]. + +It is necessary to smelt gold ore either outside the blast furnace in a +crucible, or inside the blast furnace; in the former case a small charge +of ore is used, in the latter a large charge of it. _Rudis_ gold, of +whatever colour it is, is crushed with a _libra_ each of sulphur and +salt, a third of a _libra_ of copper, and a quarter of a _libra_ of +argol; they should be melted in a crucible on a slow fire for three +hours, then the alloy is put into molten silver that it may melt more +rapidly. Or a _libra_ of the same crude gold, crushed up, is mixed +together with half a _libra_ of _stibium_ likewise crushed, and put into +a crucible with half an _uncia_ of copper filings, and heated until they +melt, then a sixth part of granulated lead is thrown into the same +crucible. As soon as the mixture emits an odour, iron-filings are added +to it, or if these are not at hand, iron hammer-scales, for both of +these break the strength of the _stibium_. When the fire consumes it, +not alone with it is some strength of the _stibium_ consumed, but some +particles of gold and also of silver, if it be mixed with the gold[29]. +When the button has been taken out of the crucible and cooled, it is +melted in a cupel, first until the antimony is exhaled, and thereafter +until the lead is separated from it. + +Crushed pyrites which contains gold is smelted in the same way; it and +the _stibium_ should be of equal weight and in truth the gold may be +made from them in a number of different ways[30]. One part of crushed +material is mixed with six parts of copper, one part of sulphur, half a +part of salt, and they are all placed in a pot and over them is poured +wine distilled by heating liquid argol in an ampulla. The pot is covered +and smeared over with lute and is put in a hot place, so that the +mixture moistened with wine may dry for the space of six days, then it +is heated for three hours over a gentle fire that it may combine more +rapidly with the lead. Finally it is put into a cupel and the gold is +separated from the lead[31]. + +Or else one _libra_ of the concentrates from washing pyrites, or other +stones to which gold adheres, is mixed with half a _libra_ of salt, half +a _libra_ of argol, a third of a _libra_ of glass-galls, a sixth of a +_libra_ of gold or silver slags, and a _sicilicus_ of copper. The +crucible into which these are put, after it has been covered with a lid, +is sealed with lute and placed in a small furnace that is provided with +small holes through which the air is drawn in, and then it is heated +until it turns red and the substances put in have alloyed; this should +take place within four or five hours. The alloy having cooled, it is +again crushed to powder and a pound of litharge is added to it; then it +is heated again in another crucible until it melts. The button is taken +out, purged of slag, and placed in a cupel, where the gold is separated +from the lead. + +Or to a _libra_ of the powder prepared from such metalliferous +concentrates, is added a _libra_ each of salt, of saltpetre, of argol, +and of glass-galls, and it is heated until it melts. When cooled and +crushed, it is washed, then to it is added a _libra_ of silver, a third +of copper filings, a sixth of litharge, and it is likewise heated again +until it melts. After the button has been purged of slag, it is put into +the cupel, and the gold and silver are separated from the lead; the gold +is parted from the silver with _aqua valens_. Or else a _libra_ of the +powder prepared from such metalliferous concentrates, a quarter of a +_libra_ of copper filings, and two _librae_ of that second powder[32] +which fuses ores, are heated until they melt. The mixture when cooled is +again reduced to powder, roasted and washed, and in this manner a blue +powder is obtained. Of this, and silver, and that second powder which +fuses ores, a _libra_ each are taken, together with three _librae_ of +lead, and a quarter of a _libra_ of copper, and they are heated together +until they melt; then the button is treated as before. Or else a _libra_ +of the powder prepared from such metalliferous concentrates, half a +_libra_ of saltpetre, and a quarter of a _libra_ of salt are heated +until they melt. The alloy when cooled is again crushed to powder, one +_libra_ of which is absorbed by four pounds of molten silver. Or else a +_libra_ of the powder made from that kind of concentrates, together with +a _libra_ of sulphur, a _libra_ and a half of salt, a third of a _libra_ +of salt made from argol, and a third of a _libra_ of copper resolved +into powder with sulphur, are heated until they melt. Afterward the lead +is re-melted, and the gold is separated from the other metals. Or else a +_libra_ of the powder of this kind of concentrates, together with two +_librae_ of salt, half a _libra_ of sulphur, and one _libra_ of +litharge, are heated, and from these the gold is melted out. By these +and similar methods concentrates containing gold, if there be a small +quantity of them or if they are very rich, can be smelted outside the +blast furnace. + +If there be much of them and they are poor, then they are smelted in the +blast furnace, especially the ore which is not crushed to powder, and +particularly when the gold mines yield an abundance of it[33]. The gold +concentrates mixed with litharge and hearth-lead, to which are added +iron-scales, are smelted in the blast furnace whose tap-hole is +intermittently closed, or else in the first or the second furnaces in +which the tap-hole is always open. In this manner an alloy of gold and +lead is obtained which is put into the cupellation furnace. Two parts of +roasted pyrites or _cadmia_ which contain gold, are put with one part of +unroasted, and are smelted together in the third furnace whose tap-hole +is always open, and are made into cakes. When these cakes have been +repeatedly roasted, they are re-smelted in the furnace whose tap-hole is +temporarily closed, or in one of the two others whose tap-holes are +always open. In this manner the lead absorbs the gold, whether pure or +argentiferous or cupriferous, and the alloy is taken to the cupellation +furnace. Pyrites, or other gold ore which is mixed with much material +that is consumed by fire and flies out of the furnace, is melted with +stone from which iron is melted, if this is at hand. Six parts of such +pyrites, or of gold ore reduced to powder and sifted, four of stone from +which iron is made, likewise crushed, and three of slaked lime, are +mixed together and moistened with water; to these are added two and a +half parts of the cakes which contain some copper, together with one and +a half parts of slag. A basketful of fragments of the cakes is thrown +into the furnace, then the mixture of other things, and then the slag. +Now when the middle part of the forehearth is filled with the molten +material which runs down from the furnace, the slags are first skimmed +off, and then the cakes made of pyrites; afterward the alloy of copper, +gold and silver, which settles at the bottom, is taken out. The cakes +are gently roasted and re-smelted with lead, and made into cakes, which +are carried to other works. The alloy of copper, gold, and silver is not +roasted, but is re-melted again in a crucible with an equal portion of +lead. Cakes are also made much richer in copper and gold than those I +spoke of. In order that the alloy of gold and silver may be made +richer, to eighteen _librae_ of it are added forty-eight _librae_ of +crude ore, three _librae_ of the stone from which iron is made, and +three-quarters of a _libra_ of the cakes made from pyrites, and mixed +with lead, all are heated together in the crucible until they melt. When +the slag and the cakes melted from pyrites have been skimmed off, the +alloy is carried to other furnaces. + +There now follows silver, of which the native silver or the lumps of +_rudis_ silver[34] obtained from the mines are not smelted in the blast +furnaces, but in small iron pans, of which I will speak at the proper +place; these lumps are heated and thrown into molten silver-lead alloy +in the cupellation furnace when the silver is being separated from the +lead, and refined. The tiny flakes or tiny lumps of silver adhering to +stones or marble or rocks, or again the same little lumps mixed with +earth, or silver not pure enough, should be smelted in the furnace of +which the tap-hole is only closed for a short time, together with cakes +melted from pyrites, with silver slags, and with stones which easily +fuse in fire of the second order. + +In order that particles of silver should not fly away[35] from the lumps +of ore consisting of minute threads of pure silver and twigs of native +silver, they are enclosed in a pot, and are placed in the same furnace +where the rest of the silver ores are being smelted. Some people smelt +lumps of native silver not sufficiently pure, in pots or triangular +crucibles, whose lids are sealed with lute. They do not place these pots +in the blast furnace, but arrange them in the assay furnace into which +the draught of the air blows through small holes. To one part of the +native silver they add three parts of powdered litharge, as many parts +of hearth-lead, half a part of galena[36], and a small quantity of salt +and iron-scales. The alloy which settles at the bottom of the other +substances in the pot is carried to the cupellation furnace, and the +slags are re-melted with the other silver slags. They crush under the +stamps and wash the pots or crucibles to which silver-lead alloy or +slags adhere, and having collected the concentrates they smelt them +together with the slags. This method of smelting _rudis_ silver, if +there is a small quantity of it, is the best, because the smallest +portion of silver does not fly out of the pot or the crucible, and get +lost. + +If bismuth ore or antimony ore or lead ore[37] contains silver, it is +smelted with the other ores of silver; likewise galena or pyrites, if +there is a small amount of it. If there be much galena, whether it +contain a large or a small amount of silver, it is smelted separately +from the others; which process I will explain a little further on. + +Because lead and copper ores and their metals have much in common with +silver ores, it is fitting that I should say a great deal concerning +them, both now and later on. Also in the same manner, pyrites are +smelted separately if there be much of them. To three parts of roasted +lead or copper ore and one part of crude ore, are added concentrates if +they were made by washing the same ore, together with slags, and all are +put in the third furnace whose tap-hole is always open. Cakes are made +from this charge, which, when they have been quenched with water, are +roasted. Of these roasted cakes generally four parts are again mixed +with one part of crude pyrites and re-melted in the same furnace. Cakes +are again made from this charge, and if there is a large amount of +copper in these cakes, copper is made immediately after they have been +roasted and re-melted; if there is little copper in the cakes they are +also roasted, but they are re-smelted with a little soft slag. In this +method the molten lead in the forehearth absorbs the silver. From the +pyritic material which floats on the top of the forehearth are made +cakes for the third time, and from them when they have been roasted and +re-smelted is made copper. Similarly, three parts of roasted +_cadmia_[38] in which there is silver, are mixed with one part of crude +pyrites, together with slag, and this charge is smelted and cakes are +made from it; these cakes having been roasted are re-smelted in the same +furnace. By this method the lead contained in the forehearth absorbs the +silver, and the silver-lead is taken to the cupellation furnace. Crude +quartz and stones which easily fuse in fire of the third order, together +with other ores in which there is a small amount of silver, ought to be +mixed with crude roasted pyrites or _cadmia_, because the roasted cakes +of pyrites or _cadmia_ cannot be profitably smelted separately. In a +similar manner earths which contain little silver are mixed with the +same; but if pyrites and _cadmia_ are not available to the smelter, he +smelts such silver ores and earths with litharge, hearth-lead, slags, +and stones which easily melt in the fire. The concentrates[39] +originating from the washing of _rudis_ silver, after first being +roasted[40] until they melt, are smelted with mixed litharge and +hearth-lead, or else, after being moistened with water, they are smelted +with cakes made from pyrites and _cadmia_. By neither of these methods +do (the concentrates) fall back in the furnace, or fly out of it, driven +by the blast of the bellows and the agitation of the fire. If the +concentrates originated from galena they are smelted with it after +having been roasted; and if from pyrites, then with pyrites. + +Pure copper ore, whether it is its own colour or is tinged with +chrysocolla or azure, and copper glance, or grey or black _rudis_ +copper, is smelted in a furnace of which the tap-hole is closed for a +very short time, or else is always open[41]. If there is a large amount +of silver in the ore it is run into the forehearth, and the greater part +of the silver is absorbed by the molten lead, and the remainder is sold +with the copper to the proprietor of the works in which silver is parted +from copper[42]. If there is a small amount of silver in the ore, no +lead is put into the forehearth to absorb the silver, and the +above-mentioned proprietors buy it in with the copper; if there be no +silver, copper is made direct. If such copper ore contains some minerals +which do not easily melt, as pyrites or _cadmia metallica fossilis_[43], +or stone from which iron is melted, then crude pyrites which easily fuse +are added to it, together with slag. From this charge, when smelted, +they make cakes; and from these, when they have been roasted as much as +is necessary and re-smelted, the copper is made. But if there be some +silver in the cakes, for which an outlay of lead has to be made, then it +is first run into the forehearth, and the molten lead absorbs the +silver. + +Indeed, _rudis_ copper ore of inferior quality, whether ash-coloured or +purple, blackish and occasionally in parts blue, is smelted in the first +furnace whose tap-hole is always open. This is the method of the +Tyrolese. To as much _rudis_ copper ore as will fill eighteen vessels, +each of which holds almost as much as seven Roman _moduli_[44], the +first smelter--for there are three--adds three cartloads of lead slags, +one cartload of schist, one fifth of a _centumpondium_ of stones which +easily fuse in the fire, besides a small quantity of concentrates +collected from copper slag and accretions, all of which he smelts for +the space of twelve hours, and from which he makes six _centumpondia_ of +primary cakes and one-half of a _centumpondium_ of alloy. One half of +the latter consists of copper and silver, and it settles to the bottom +of the forehearth. In every _centumpondium_ of the cakes there is half a +_libra_ of silver and sometimes half an _uncia_ besides; in the half of +a _centumpondium_ of the alloy there is a _bes_ or three-quarters of +silver. In this way every week, if the work is for six days, thirty-six +_centumpondia_ of cakes are made and three _centumpondia_ of alloy, in +all of which there is often almost twenty-four _librae_ of silver. The +second smelter separates from the primary cakes the greater part of the +silver by absorbing it in lead. To eighteen _centumpondia_ of cakes made +from crude copper ore, he adds twelve _centumpondia_ of hearth-lead and +litharge, three _centumpondia_ of stones from which lead is smelted, +five _centumpondia_ of hard cakes rich in silver, and two _centumpondia_ +of exhausted liquation cakes[45]; he adds besides, some of the slags +resulting from smelting crude copper, together with a small quantity of +concentrates made from accretions, all of which he melts for the space +of twelve hours, and makes eighteen _centumpondia_ of secondary cakes, +and twelve _centumpondia_ of copper-lead-silver alloy; in each +_centumpondium_ of the latter there is half a _libra_ of silver. After +he has taken off the cakes with a hooked bar, he pours the alloy out +into copper or iron moulds; by this method they make four cakes of +alloy, which are carried to the works in which silver is parted from +copper. On the following day, the same smelter, taking eighteen +_centumpondia_ of the secondary cakes, again adds twelve _centumpondia_ +of hearth-lead and litharge, three _centumpondia_ of stones from which +lead is smelted, five _centumpondia_ of hard cakes rich in silver, +together with slags from the smelting of the primary cakes, and with +concentrates washed from the accretions which are usually made at that +time. This charge is likewise smelted for the space of twelve hours, and +he makes as many as thirteen _centumpondia_ of tertiary cakes and eleven +_centumpondia_ of copper-lead-silver alloy, each _centumpondium_ of +which contains one-third of a _libra_ and half an _uncia_ of silver. +When he has skimmed off the tertiary cakes with a hooked bar, the alloy +is poured into copper moulds, and by this method four cakes of alloy are +made, which, like the preceding four cakes of alloy, are carried to the +works in which silver is parted from copper. By this method the second +smelter makes primary cakes on alternate days and secondary cakes on the +intermediate days. The third smelter takes eleven cartloads of the +tertiary cakes and adds to them three cartloads of hard cakes poor in +silver, together with the slag from smelting the secondary cakes, and +the concentrates from the accretions which are usually made at that +time. From this charge when smelted, he makes twenty _centumpondia_ of +quaternary cakes, which are called "hard cakes," and also fifteen +_centumpondia_ of those "hard cakes rich in silver," each +_centumpondium_ of which contains a third of a _libra_ of silver. These +latter cakes the second smelter, as I said before, adds to the primary +and secondary cakes when he re-melts them. In the same way, from eleven +cartloads of quaternary cakes thrice roasted, he makes the "final" +cakes, of which one _centumpondium_ contains only half an _uncia_ of +silver. In this operation he also makes fifteen _centumpondia_ of "hard +cakes poor in silver," in each _centumpondium_ of which is a sixth of a +_libra_ of silver. These hard cakes the third smelter, as I have said, +adds to the tertiary cakes when he re-smelts them, while from the +"final" cakes, thrice roasted and re-smelted, is made black copper[46]. + +The _rudis_ copper from which pure copper is made, if it contains little +silver or if it does not easily melt, is first smelted in the third +furnace of which the tap-hole is always open; and from this are made +cakes, which after being seven times roasted are re-smelted, and from +these copper is melted out; the cakes of copper are carried to a furnace +of another kind, in which they are melted for the third time, in order +that in the copper "bottoms" there may be more silver, while in the +"tops" there may be less, which process is explained in Book XI. + +Pyrites, when they contain not only copper, but also silver, are +smelted in the manner I described when I treated of ores of silver. But +if they are poor in silver, and if the copper which is melted out of +them cannot easily be treated, they are smelted according to the method +which I last explained. + +Finally, the copper schists containing bitumen or sulphur are roasted, +and then smelted with stones which easily fuse in a fire of the second +order, and are made into cakes, on the top of which the slags float. +From these cakes, usually roasted seven times and re-melted, are melted +out slags and two kinds of cakes; one kind is of copper and occupies the +bottom of the crucible, and these are sold to the proprietors of the +works in which silver is parted from copper; the other kind of cakes are +usually re-melted with primary cakes. If the schist contains but a small +amount of copper, it is burned, crushed under the stamps, washed and +sieved, and the concentrates obtained from it are melted down; from this +are made cakes from which, when roasted, copper is made. If either +chrysocolla or azure, or yellow or black earth containing copper and +silver, adheres to the schist, it is not washed, but is crushed and +smelted with stones which easily fuse in fire of the second order. + +Lead ore, whether it be _molybdaena_[47], pyrites, (galena?) or stone +from which it is melted, is often smelted in a special furnace, of which +I have spoken above, but no less often in the third furnace of which the +tap-hole is always open. The hearth and forehearth are made from powder +containing a small portion of iron hammer-scales; iron slag forms the +principal flux for such ores; both of these the expert smelters consider +useful and to the owner's advantage, because it is the nature of iron to +attract lead. If it is _molybdaena_ or the stone from which lead is +smelted, then the lead runs down from the furnace into the forehearth, +and when the slags have been skimmed off, the lead is poured out with a +ladle. If pyrites are smelted, the first to flow from the furnace into +the forehearth, as may be seen at Goslar, is a white molten substance, +injurious and noxious to silver, for it consumes it. For this reason the +slags which float on the top having been skimmed off, this substance is +poured out; or if it hardens, then it is taken out with a hooked bar; +and the walls of the furnace exude the same substance[48]. Then the +_stannum_ runs out of the furnace into the forehearth; this is an alloy +of lead and silver. From the silver-lead alloy they first skim off the +slags, not rarely white, as some pyrites[49] are, and afterward they +skim off the cakes of pyrites, if there are any. In these cakes there is +usually some copper; but since there is usually but a very small +quantity, and as the forest charcoal is not abundant, no copper is made +from them. From the silver-lead poured into iron moulds they likewise +make cakes; when these cakes have been melted in the cupellation +furnace, the silver is parted from the lead, because part of the lead is +transformed into litharge and part into hearth-lead, from which in the +blast furnace on re-melting they make de-silverized lead, for in this +lead each _centumpondium_ contains only a _drachma_ of silver, when +before the silver was parted from it each _centumpondium_ contained more +or less than three _unciae_ of silver[50]. + +The little black stones[51] and others from which tin is made, are +smelted in their own kind of furnace, which should be narrower than the +other furnaces, that there may be only the small fire which is necessary +for this ore. These furnaces are higher, that the height may compensate +for the narrowness and make them of almost the same capacity as the +other furnaces. At the top, in front, they are closed and on the other +side they are open, where there are steps, because they cannot have the +steps in front on account of the forehearth; the smelters ascend by +these steps to put the tin-stone into the furnace. The hearth of the +furnace is not made of powdered earth and charcoal, but on the floor of +the works are placed sandstones which are not too hard; these are set on +a slight slope, and are two and three-quarters feet long, the same +number of feet wide, and two feet thick, for the thicker they are the +longer they last in the fire. Around them is constructed a rectangular +furnace eight or nine feet high, of broad sandstones, or of those common +substances which by nature are composed of diverse materials[52]. On the +inside the furnace is everywhere evenly covered with lute. The upper +part of the interior is two feet long and one foot wide, but below it is +not so long and wide. Above it are two hood-walls, between which the +fumes ascend from the furnace into the dust chamber, and through this +they escape by a narrow opening in the roof. The sandstones are sloped +at the bed of the furnace, so that the tin melted from the tin-stone may +flow through the tap-hole of the furnace into the forehearth.[53] + +As there is no need for the smelters to have a fierce fire, it is not +necessary to place the nozzles of the bellows in bronze or iron pipes, +but only through a hole in the furnace wall. They place the bellows +higher at the back so that the blast from the nozzles may blow straight +toward the tap-hole of the furnace. That it may not be too fierce, the +nozzles are wide, for if the fire were fiercer, tin could not be melted +out from the tin-stone, as it would be consumed and turned into ashes. +Near the steps is a hollowed stone, in which is placed the tin-stone to +be smelted; as often as the smelter throws into the furnace an iron +shovel-ful of this tin-stone, he puts on charcoal that was first put +into a vat and washed with water to be cleansed from the grit and small +stones which adhere to it, lest they melt at the same time as the +tin-stone and obstruct the tap-hole and impede the flow of tin from the +furnace. The tap-hole of the furnace is always open; in front of it is a +forehearth a little more than half a foot deep, three-quarters of two +feet long and one foot wide; this is lined with lute, and the tin from +the tap-hole flows into it. On one side of the forehearth is a low wall, +three-quarters of a foot wider and one foot longer than the forehearth, +on which lies charcoal powder. On the other side the floor of the +building slopes, so that the slags may conveniently run down and be +carried away. As soon as the tin begins to run from the tap-hole of the +furnace into the forehearth, the smelter scrapes down some of the +powdered charcoal into it from the wall, so that the slags may be +separated from the hot metal, and so that it may be covered, lest any +part of it, being very hot, should fly away with the fumes. If after the +slag has been skimmed off, the powder does not cover up the whole of the +tin, the smelter draws a little more charcoal off the wall with a +scraper. After he has opened the tap-hole of the forehearth with a +tapping-bar, in order that the tin can flow into the tapping-pot, +likewise smeared with lute, he again closes the tap-hole with pure lute +or lute mixed with powdered charcoal. The smelter, if he be diligent and +experienced, has brooms at hand with which he sweeps down the walls +above the furnace; to these walls and to the dust chamber minute +tin-stones sometimes adhere with part of the fumes. If he be not +sufficiently experienced in these matters and has melted at the same +time all of the tin-stone,--which is commonly of three sizes, large, +medium, and very small,--not a little waste of the proprietor's tin +results; because, before the large or the medium sizes have melted, the +small have either been burnt up in the furnace, or else, flying up from +it, they not only adhere to the walls but also fall in the dust chamber. +The owner of the works has the sweepings by right from the owner of the +ore. For the above reasons the most experienced smelter melts them down +separately; indeed, he melts the very small size in a wider furnace, the +medium in a medium-sized furnace, and the largest size in the narrowest +furnace. When he melts down the small size he uses a gentle blast from +the bellows, with the medium-sized a moderate one, with the large size a +violent blast; and when he smelts the first size he needs a slow fire, +for the second a medium one, and for the third a fierce one; yet he uses +a much less fierce fire than when he smelts the ores of gold, silver, or +copper. When the workmen have spent three consecutive days and nights in +this work, as is usual, they have finished their labours; in this time +they are able to melt out a large weight of small sized tin-stone which +melts quickly, but less of the large ones which melt slowly, and a +moderate quantity of the medium-sized which holds the middle course. +Those who do not smelt the tin-stone in furnaces made sometimes wide, +sometimes medium, or sometimes narrow, in order that great loss should +not be occasioned, throw in first the smallest size, then the medium, +then the large size, and finally those which are not quite pure; and the +blast of the bellows is altered as required. In order that the tin-stone +thrown into the furnace should not roll off from the large charcoal into +the forehearth before the tin is melted out of it, the smelter uses +small charcoal; first some of this moistened with water is placed in the +furnace, and then he frequently repeats this succession of charcoal and +tin-stone. + +The tin-stone, collected from material which during the summer was +washed in a ditch through which a stream was diverted, and during the +winter was screened on a perforated iron plate, is smelted in a furnace +a palm wider than that in which the fine tin-stone dug out of the earth +is smelted. For the smelting of these, a more vigorous blast of the +bellows and a fiercer fire is needed than for the smelting of the large +tin-stone. Whichever kind of tin-stone is being smelted, if the tin +first flows from the furnace, much of it is made, and if slags first +flow from the furnace, then only a little. It happens that the tin-stone +is mixed with the slags when it is either less pure or ferruginous--that +is, not enough roasted--and is imperfect when put into the furnace, or +when it has been put in in a larger quantity than was necessary; then, +although it may be pure and melt easily, the ore either runs out of the +furnace at the same time, mixed with the slags, or else it settles so +firmly at the bottom of the furnace that the operation of smelting being +necessarily interrupted, the furnace freezes up. + +[Illustration 415 (Tin smelting Furnaces): A--Furnace. B--Its tap-hole. +C--Forehearth. D--Its tap-hole. E--Slags. F--Scraper. G--Dipping-pot. +H--Walls of the chimney. I--Broom. K--Copper plate. L--Latticework bars. +M--Iron seal or die. N--Hammer.] + +The tap-hole of the forehearth is opened and the tin is diverted into +the dipping-pot, and as often as the slags flow down the sloping floor +of the building they are skimmed off with a rabble; as soon as the tin +has run out of the forehearth, the tap-hole is again closed up with lute +mixed with powdered charcoal. Glowing coals are put in the dipping-pot +so that the tin, after it has run out, should not get chilled. If the +metal is so impure that nothing can be made from it, the material which +has run out is made into cakes to be re-smelted in the hearth, of which +I shall have something to say later; if the metal is pure, it is poured +immediately upon thick copper plates, at first in straight lines and +then transversely over these to make a lattice. Each of these lattice +bars is impressed with an iron die; if the tin was melted out of ore +excavated from mines, then one stamp only, namely, that of the +Magistrate, is usually imprinted, but if it is made from tin-stone +collected on the ground after washing, then it is impressed with two +seals, one the Magistrate's and the other a fork which the washers use. +Generally, three of this kind of lattice bars are beaten and amalgamated +into one mass with a wooden mallet. + +The slags that are skimmed off are afterward thrown with an iron shovel +into a small trough hollowed from a tree, and are cleansed from +charcoal by agitation; when taken out they are broken up with a square +iron mallet, and then they are re-melted with the fine tin-stone next +smelted. There are some who crush the slags three times under wet stamps +and re-melt them three times; if a large quantity of this be smelted +while still wet, little tin is melted from it, because the slag, soon +melted again, flows from the furnace into the forehearth. Under the wet +stamps are also crushed the lute and broken rock with which such +furnaces are lined, and also the accretions, which often contain fine +tin-stone, either not melted or half-melted, and also prills of tin. The +tin-stone not yet melted runs out through the screen into a trough, and +is washed in the same way as tin-stone, while the partly melted and the +prills of tin are taken from the mortar-box and washed in the sieve on +which not very minute particles remain, and thence to the canvas strake. +The soot which adheres to that part of the chimney which emits the +smoke, also often contains very fine tin-stone which flies from the +furnace with the fumes, and this is washed in the strake which I have +just mentioned, and in other sluices. The prills of tin and the partly +melted tin-stone that are contained in the lute and broken rock with +which the furnace is lined, and in the remnants of the tin from the +forehearth and the dipping-pot, are smelted together with the tin-stone. + +When tin-stone has been smelted for three days and as many nights in a +furnace prepared as I have said above, some little particles of the rock +from which the furnace is constructed become loosened by the fire and +fall down; and then the bellows being taken away, the furnace is broken +through at the back, and the accretions are first chipped off with +hammers, and afterward the whole of the interior of the furnace is +re-fitted with the prepared sandstone, and again evenly lined with lute. +The sandstone placed on the bed of the furnace, if it has become faulty, +is taken out, and another is laid down in its place; those rocks which +are too large the smelter chips off and fits with a sharp pick. + +[Illustration 417 (Tin smelting Furnaces): A--Furnaces. B--Forehearths. +C--Their tap-holes. D--Dipping-pots. E--Pillars. F--Dust-chamber. +G--Window. H--Chimneys. I--Tub in which the coals are washed.] + +Some build two furnaces against the wall just like those I have +described, and above them build a vaulted ceiling supported by the wall +and by four pillars. Through holes in the vaulted ceiling the fumes from +the furnaces ascend into a dust chamber, similar to the one described +before, except that there is a window on each side and there is no door. +The smelters, when they have to clear away the flue-dust, mount by the +steps at the side of the furnaces, and climb by ladders into the dust +chamber through the apertures in the vaulted ceilings over the furnaces. +They then remove the flue-dust from everywhere and collect it in +baskets, which are passed from one to the other and emptied. This dust +chamber differs from the other described, in the fact that the chimneys, +of which it has two, are not dissimilar to those of a house; they +receive the fumes which, being unable to escape through the upper part +of the chamber, are turned back and re-ascend and release the tin; thus +the tin set free by the fire and turned to ash, and the little +tin-stones which fly up with the fumes, remain in the dust chamber or +else adhere to copper plates in the chimney. + +[Illustration 418 (Refining Tin): A--Hearths. B--Dipping-pots. C--Wood. +D--Cakes. E--Ladle. F--Copper plate. G--Lattice-shaped bars. H--Iron +dies. I--Wooden mallet. K--Mass of tin bars. L--Shovel.] + +If the tin is so impure that it cracks when struck with the hammer, it +is not immediately made into lattice-like bars, but into the cakes which +I have spoken of before, and these are refined by melting again on a +hearth. This hearth consists of sandstones, which slope toward the +centre and a little toward a dipping-pot; at their joints they are +covered with lute. Dry logs are arranged on each side, alternately +upright and lengthwise, and more closely in the middle; on this wood are +placed five or six cakes of tin which all together weigh about six +_centumpondia_; the wood having been kindled, the tin drips down and +flows continuously into the dipping-pot which is on the floor. The +impure tin sinks to the bottom of this dipping-pot and the pure tin +floats on the top; then both are ladled out by the master, who first +takes out the pure tin, and by pouring it over thick plates of copper +makes lattice-like bars. Afterward he takes out the impure tin from +which he makes cakes; he discriminates between them, when he ladles and +pours, by the ease or difficulty of the flow. One _centumpondium_ of the +lattice-like bars sells for more than a _centumpondium_ of cakes, for +the price of the former exceeds the price of the latter by a gold +coin[54]. These lattice-like bars are lighter than the others, and when +five of them are pounded and amalgamated with a wooden mallet, a mass is +made which is stamped with an iron die. There are some who do not make a +dipping-pot on the floor for the tin to run into, but in the hearth +itself; out of this the master, having removed the charcoal, ladles the +tin and pours it over the copper-plate. The dross which adheres to the +wood and the charcoal, having been collected, is re-smelted in the +furnace. + +[Illustration 419 (Blast Furnaces): A--Furnace. B--Bellows. C--Iron +Disc. D--Nozzle. E--Wooden Disc. F--Blow-hole. G--Handle. H--Haft. +I--Hoops. K--Masses of tin.] + +Some of the Lusitanians melt tin from tin-stone in small furnaces. They +use round bellows made of leather, of which the fore end is a round iron +disc and the rear end a disc of wood; in a hole in the former is fixed +the nozzle, in the middle of the latter the blow-hole. Above this is the +handle or haft, which draws open the round bellows and lets in the air, +or compresses it and drives the air out. Between the discs are several +iron hoops to which the leather is fastened, making such folds as are to +be seen in paper lanterns that are folded together. Since this kind of +bellows does not give a vigorous blast, because they are drawn apart and +compressed slowly, the smelter is not able during a whole day to smelt +much more than half a _centumpondium_ of tin. + +[Illustration 422 (Iron smelting Furnaces): A--Hearth. B--Heap. +C--Slag-vent. D--Iron mass. E--Wooden mallets. F--Hammer. G--Anvil.] + +Very good iron ore is smelted[55] in a furnace almost like the +cupellation furnace. The hearth is three and a half feet high, and five +feet long and wide; in the centre of it is a crucible a foot deep and +one and a half feet wide, but it may be deeper or shallower, wider or +narrower, according to whether more or less ore is to be made into iron. +A certain quantity of iron ore is given to the master, out of which he +may smelt either much or little iron. He being about to expend his skill +and labour on this matter, first throws charcoal into the crucible, and +sprinkles over it an iron shovel-ful of crushed iron ore mixed with +unslaked lime. Then he repeatedly throws on charcoal and sprinkles it +with ore, and continues this until he has slowly built up a heap; it +melts when the charcoal has been kindled and the fire violently +stimulated by the blast of the bellows, which are skilfully fixed in a +pipe. He is able to complete this work sometimes in eight hours, +sometimes in ten; and again sometimes in twelve. In order that the heat +of the fire should not burn his face, he covers it entirely with a cap, +in which, however, there are holes through which he may see and breathe. +At the side of the hearth is a bar which he raises as often as is +necessary, when the bellows blow too violent a blast, or when he adds +more ore and charcoal. He also uses the bar to draw off the slags, or to +open or close the gates of the sluice, through which the waters flow +down on to the wheel which turns the axle that compresses the bellows. +In this sensible way, iron is melted out and a mass weighing two or +three _centumpondia_ may be made, providing the iron ore was rich. When +this is done the master opens the slag-vent with the tapping-bar, and +when all has run out he allows the iron mass to cool. Afterward he and +his assistant stir the iron with the bar, and then in order to chip off +the slags which had until then adhered to it, and to condense and +flatten it, they take it down from the furnace to the floor, and beat it +with large wooden mallets having slender handles five feet long. +Thereupon it is immediately placed on the anvil, and repeatedly beaten +by the large iron hammer that is raised by the cams of an axle turned by +a water-wheel. Not long afterward it is taken up with tongs and placed +under the same hammer, and cut up with a sharp iron into four, five, or +six pieces, according to whether it is large or small. These pieces, +after they have been re-heated in the blacksmith's forge and again +placed on the anvil, are shaped by the smith into square bars or into +ploughshares or tyres, but mainly into bars. Four, six, or eight of +these bars weigh one-fifth of a _centumpondium_, and from these they +make various implements. During the blows from the hammer by which it is +shaped by the smith, a youth pours water with a ladle on to the glowing +iron, and this is why the blows make such a loud sound that they may be +heard a long distance from the works. The masses, if they remain and +settle in the crucible of the furnace in which the iron is smelted, +become hard iron which can only be hammered with difficulty, and from +these they make the iron-shod heads for the stamps, and such-like very +hard articles. + +[Illustration 424 (Iron smelting Furnaces): A--Furnace. B--Stairs. +C--Ore. D--Charcoal.] + +But to iron ore which is cupriferous, or which when heated[56] melts +with difficulty, it is necessary for us to give a fiercer fire and more +labour; because not only must we separate the parts of it in which there +is metal from those in which there is no metal, and break it up by dry +stamps, but we must also roast it, so that the other metals and noxious +juices may be exhaled; and we must wash it, so that the lighter parts +may be separated from it. Such ores are smelted in a furnace similar to +the blast furnace, but much wider and higher, so that it may hold a +great quantity of ore and much charcoal; mounting the stairs at the side +of the furnace, the smelters fill it partly with fragments of ore not +larger than nuts, and partly with charcoal; and from this kind of ore +once or twice smelted they make iron which is suitable for re-heating in +the blacksmith's forge, after it is flattened out with the large iron +hammer and cut into pieces with the sharp iron. + +[Illustration 425 (Steel making Furnaces): A--Forge. B--Bellows. +C--Tongs. D--Hammer. E--Cold stream.] + +By skill with fire and fluxes is made that kind of iron from which steel +is made, which the Greeks call [Greek: stomôma]. Iron should be selected +which is easy to melt, is hard and malleable. Now although iron may be +smelted from ore which contains other metals, yet it is then either soft +or brittle; such (iron) must be broken up into small pieces when it is +hot, and then mixed with crushed stone which melts. Then a crucible is +made in the hearth of the smith's furnace, from the same moistened +powder from which are made the forehearths in front of the furnaces in +which ores of gold or silver are smelted; the width of this crucible is +about one and a half feet and the depth one foot. The bellows are so +placed that the blast may be blown through the nozzle into the middle of +the crucible. Then the whole of the crucible is filled with the best +charcoal, and it is surrounded by fragments of rock to hold in place the +pieces of iron and the superimposed charcoal. As soon as all the +charcoal is kindled and the crucible is glowing, a blast is blown from +the bellows and the master pours in gradually as much of the mixture of +iron and flux as he wishes. Into the middle of this, when it is melted, +he puts four iron masses each weighing thirty pounds, and heats them for +five or six hours in a fierce fire; he frequently stirs the melted iron +with a bar, so that the small pores in each mass absorb the minute +particles, and these particles by their own strength consume and expand +the thick particles of the masses, which they render soft and similar to +dough. Afterward the master, aided by his assistant, takes out a mass +with the tongs and places it on the anvil, where it is pounded by the +hammer which is alternately raised and dropped by means of the +water-wheel; then, without delay, while it is still hot, he throws it +into water and tempers it; when it is tempered, he places it again on +the anvil, and breaks it with a blow from the same hammer. Then at once +examining the fragments, he decides whether the iron in some part or +other, or as a whole, appears to be dense and changed into steel; if so, +he seizes one mass after another with the tongs, and taking them out he +breaks them into pieces. Afterward he heats the mixture up again, and +adds a portion afresh to take the place of that which has been absorbed +by the masses. This restores the energy of that which is left, and the +pieces of the masses are again put back into the crucible and made +purer. Each of these, after having been heated, is seized with the +tongs, put under the hammer and shaped into a bar. While they are still +glowing, he at once throws them into the very coldest nearby running +water, and in this manner, being suddenly condensed, they are changed +into pure steel, which is much harder and whiter than iron. + +The ores of the other metals are not smelted in furnaces. Quicksilver +ores and also antimony are melted in pots, and bismuth in troughs. + +[Illustration 427 (Quicksilver distillation Furnaces): A--Hearth. +B--Poles. C--Hearth without fire in which the pots are placed. D--Rocks. +E--Rows of pots. F--Upper pots. G--Lower pots.] + +I will first speak of quicksilver. This is collected when found in pools +formed from the outpourings of the veins and stringers; it is cleansed +with vinegar and salt, and then it is poured into canvas or soft +leather, through which, when squeezed and compressed, the quicksilver +runs out into a pot or pan. The ore of quicksilver is reduced in double +or single pots. If in double pots, then the upper one is of a shape not +very dissimilar to the glass ampullas used by doctors, but they taper +downward toward the bottom, and the lower ones are little pots similar +to those in which men and women make cheese, but both are larger than +these; it is necessary to sink the lower pots up to the rims in earth, +sand, or ashes. The ore, broken up into small pieces is put into the +upper pots; these having been entirely closed up with moss, are placed +upside down in the openings of the lower pots, where they are joined +with lute, lest the quicksilver which takes refuge in them should be +exhaled. There are some who, after the pots have been buried, do not +fear to leave them uncemented, and who boast that they are able to +produce no less weight of quicksilver than those who do cement them, but +nevertheless cementing with lute is the greatest protection against +exhalation. In this manner seven hundred pairs of pots are set together +in the ground or on a hearth. They must be surrounded on all sides with +a mixture consisting of crushed earth and charcoal, in such a way that +the upper pots protrude to a height of a palm above it. On both sides of +the hearth rocks are first laid, and upon them poles, across which the +workmen place other poles transversely; these poles do not touch the +pots, nevertheless the fire heats the quicksilver, which fleeing from +the heat is forced to run down through the moss into the lower pots. If +the ore is being reduced in the upper pots, it flees from them, wherever +there is an exit, into the lower pots, but if the ore on the contrary is +put in the lower pots the quicksilver rises into the upper pot or into +the operculum, which, together with the gourd-shaped vessels, are +cemented to the upper pots. + +The pots, lest they should become defective, are moulded from the best +potters' clay, for if there are defects the quicksilver flies out in the +fumes. If the fumes give out a very sweet odour it indicates that the +quicksilver is being lost, and since this loosens the teeth, the +smelters and others standing by, warned of the evil, turn their backs to +the wind, which drives the fumes in the opposite direction; for this +reason, the building should be open around the front and the sides, and +exposed to the wind. If these pots are made of cast copper they last a +long time in the fire. This process for reducing the ores of quicksilver +is used by most people. + +In a similar manner the antimony ore,[57] if free from other metals, is +reduced in upper pots which are twice as large as the lower ones. Their +size, however, depends on the cakes, which have not the same weight +everywhere; for in some places they are made to weigh six _librae_, in +other places ten, and elsewhere twenty. When the smelter has concluded +his operation, he extinguishes the fire with water, removes the lids +from the pots, throws earth mixed with ash around and over them, and +when they have cooled, takes out the cakes from the pots. + +[Illustration 429 (Quicksilver distillation Furnaces): A--Pots. +B--Opercula. C--Nozzles. D--Gourd-shaped earthenware vessels.] + +Other methods for reducing quicksilver are given below. Big-bellied +pots, having been placed in the upper rectangular open part of a +furnace, are filled with the crushed ore. Each of these pots is covered +with a lid with a long nozzle--commonly called a _campana_--in the shape +of a bell, and they are cemented. Each of the small earthenware vessels +shaped like a gourd receives two of these nozzles, and these are +likewise cemented. Dried wood having been placed in the lower part of +the furnace and kindled, the ore is heated until all the quicksilver has +risen into the operculum which is over the pot; it then flows from the +nozzle and is caught in the earthenware gourd-shaped vessel. + +[Illustration 430 (Quicksilver distillation Furnaces): A--Enclosed +chamber. B--Door. C--Little windows. D--Mouths through the walls. +E--Furnace in the enclosed chamber. F--Pots.] + +Others build a hollow vaulted chamber, of which the paved floor is made +concave toward the centre. Inside the thick walls of the chamber are the +furnaces. The doors through which the wood is put are in the outer part +of the same wall. They place the pots in the furnaces and fill them with +crushed ore, then they cement the pots and the furnaces on all sides +with lute, so that none of the vapour may escape from them, and there is +no entrance to the furnaces except through their mouths. Between the +dome and the paved floor they arrange green trees, then they close the +door and the little windows, and cover them on all sides with moss and +lute, so that none of the quicksilver can exhale from the chamber. After +the wood has been kindled the ore is heated, and exudes the +quicksilver; whereupon, impatient with the heat, and liking the cold, it +escapes to the leaves of the trees, which have a cooling power. When the +operation is completed the smelter extinguishes the fire, and when all +gets cool he opens the door and the windows, and collects the +quicksilver, most of which, being heavy, falls of its own accord from +the trees, and flows into the concave part of the floor; if all should +not have fallen from the trees, they are shaken to make it fall. + +[Illustration 431 (Quicksilver distillation Furnaces): A--Larger pot. +B--Smaller. C--Tripod. D--Tub in which the sand is washed.] + +The following is the fourth method of reducing ores of quicksilver. A +larger pot standing on a tripod is filled with crushed ore, and over the +ore is put sand or ashes to a thickness of two digits, and tamped; then +in the mouth of this pot is inserted the mouth of another smaller pot +and cemented with lute, lest the vapours are emitted. The ore heated by +the fire exhales the quicksilver, which, penetrating through the sand or +the ashes, takes refuge in the upper pot, where condensing into drops it +falls back into the sand or the ashes, from which the quicksilver is +washed and collected. + +[Illustration 432 (Quicksilver distillation Furnaces): A--Pots. B--Lids. +C--Stones. D--Furnace.] + +The fifth method is not very unlike the fourth. In the place of these +pots are set other pots, likewise of earthenware, having a narrow bottom +and a wide mouth. These are nearly filled with crushed ore, which is +likewise covered with ashes to a depth of two digits and tamped in. The +pots are covered with lids a digit thick, and they are smeared over on +the inside with liquid litharge, and on the lid are placed heavy stones. +The pots are set on the furnace, and the ore is heated and similarly +exhales quicksilver, which fleeing from the heat takes refuge in the +lid; on congealing there, it falls back into the ashes, from which, when +washed, the quicksilver is collected. + +By these five methods quicksilver may be made, and of these not one is +to be despised or repudiated; nevertheless, if the mine supplies a great +abundance of ore, the first is the most expeditious and practical, +because a large quantity of ore can be reduced at the same time without +great expense.[58] + +[Illustration 434 (Bismuth Smelting): A--Pit across which wood is +placed. B--Forehearth. C--Ladle. D--Iron mould. E--Cakes. F--Empty pot +lined with stones in layers. G--Troughs. H--Pits dug at the foot of the +troughs. I--Small wood laid over the troughs. K--Wind.] + +Bismuth[59] ore, free from every kind of silver, is smelted by various +methods. First a small pit is dug in the dry ground; into this +pulverised charcoal is thrown and tamped in, and then it is dried with +burning charcoal. Afterward, thick dry pieces of beech wood are placed +over the pit, and the bismuth ore is thrown on it. As soon as the +kindled wood burns, the heated ore drips with bismuth, which runs down +into the pit, from which when cooled the cakes are removed. Because +pieces of burnt wood, or often charcoal and occasionally slag, drop into +the bismuth which collects in the pit, and make it impure, it is put +back into another kind of crucible to be melted, so that pure cakes may +be made. There are some who, bearing these things in mind, dig a pit on +a sloping place and below it put a forehearth, into which the bismuth +continually flows, and thus remains clean; then they take it out with +ladles and pour it into iron pans lined inside with lute, and make cakes +of it. They cover such pits with flat stones, whose joints are besmeared +with a lute of mixed dust and crushed charcoal, lest the joints should +absorb the molten bismuth. Another method is to put the ore in troughs +made of fir-wood and placed on sloping ground; they place small firewood +over it, kindling it when a gentle wind blows, and thus the ore is +heated. In this manner the bismuth melts and runs down from the troughs +into a pit below, while there remains slag, or stones, which are of a +yellow colour, as is also the wood laid across the pit. These are also +sold. + +[Illustration 435 (Bismuth Smelting): A--Wood. B--Bricks. C--Pans. +D--Furnace. E--Crucible. F--Pipe. G--Dipping-pot.] + +Others reduce the ore in iron pans as next described. They lay small +pieces of dry wood alternately straight and transversely upon bricks, +one and a half feet apart, and set fire to it. Near it they put small +iron pans lined on the inside with lute, and full of broken ore; then +when the wind blows the flame of the fierce fire over the pans, the +bismuth drips out of the ore; wherefore, in order that it may run, the +ore is stirred with the tongs; but when they decide that all the bismuth +is exuded, they seize the pans with the tongs and remove them, and pour +out the bismuth into empty pans, and by turning many into one they make +cakes. Others reduce the ore, when it is not mixed with _cadmia_,[60] in +a furnace similar to the iron furnace. In this case they make a pit and +a crucible of crushed earth mixed with pulverised charcoal, and into it +they put the broken ore, or the concentrates from washing, from which +they make more bismuth. If they put in ore, they reduce it with charcoal +and small dried wood mixed, and if concentrates, they use charcoal only; +they blow both materials with a gentle blast from a bellows. From the +crucible is a small pipe through which the molten bismuth runs down into +a dipping-pot, and from this cakes are made. + +[Illustration 436 (Bismuth Smelting): A--Hearth in which ore is melted. +B--Hearth on which lie drops of bismuth. C--Tongs. D--Basket. E--Wind.] + +On a dump thrown up from the mines, other people construct a hearth +exposed to the wind, a foot high, three feet wide, and four and a half +feet long. It is held together by four boards, and the whole is thickly +coated at the top with lute. On this hearth they first put small dried +sticks of fir wood, then over them they throw broken ore; then they lay +more wood over it, and when the wind blows they kindle it. In this +manner the bismuth drips out of the ore, and afterward the ashes of the +wood consumed by the fire and the charcoals are swept away. The drops of +bismuth which fall down into the hearth are congealed by the cold, and +they are taken away with the tongs and thrown into a basket. From the +melted bismuth they make cakes in iron pans. + +[Illustration 437 (Bismuth Smelting): A--Box. B--Pivot. C--Transverse +wood beams. D--Grate. E--Its feet. F--Burning wood. G--Stick. H--Pans in +which the bismuth is melted. I--Pans for moulds. K--Cakes. L--Fork. +M--Brush.] + +Others again make a box eight feet long, four feet wide, and two feet +high, which they fill almost full of sand and cover with bricks, thus +making the hearth. The box has in the centre a wooden pivot, which turns +in a hole in two beams laid transversely one upon the other; these beams +are hard and thick, are sunk into the ground, both ends are perforated, +and through these holes wedge-shaped pegs are driven, in order that the +beams may remain fixed, and that the box may turn round, and may be +turned toward the wind from whichever quarter of the sky in may blow. In +such a hearth they put an iron grate, as long and wide as the box and +three-quarters of a foot high; it has six feet, and there are so many +transverse bars that they almost touch one another. On the grate they +lay pine-wood and over it broken ore, and over this they again lay +pine-wood. When it has been kindled the ore melts, out of which the +bismuth drips down; since very little wood is burned, this is the most +profitable method of smelting the bismuth. The bismuth drips through the +grate on to the hearth, while the other things remain upon the grate +with the charcoal. When the work is finished, the workman takes a stick +from the hearth and overturns the grate, and the things which have been +accumulated on it; with the brush he sweeps up the bismuth and collects +it in a basket, and then he melts it in an iron pan and makes cakes. As +soon as possible after it is cool, he turns the pans over, so that the +cakes may fall out, using for this purpose a two-pronged fork of which +one prong is again forked. And immediately afterward he returns to his +labours. + + END OF BOOK IX. + + +FOOTNOTES: + +[1] The history of the fusion of ores and of metals is the history of +individual processes, and such information as we have been able to +discover upon the individual methods previous to Agricola we give on the +pages where such processes are discussed. In general the records of the +beginnings of metallurgy are so nebular that, if one wishes to shirk the +task, he can adopt the explanation of William Pryce one hundred and +fifty years ago: "It is very probable that the nature and use of Metals +were not revealed to Adam in his state of innocence: the toil and labour +necessary to procure and use those implements of the iron age could not +be known, till they made part of the curse incurred by his fall: 'In the +sweat of thy face shalt thou eat bread, till thou return unto the +ground; in sorrow shalt thou eat of it all the days of thy life' +(Genesis). That they were very early discovered, however, is manifest +from the Mosaick account of Tubal Cain, who was the first instructor of +every artificer in Brass [_sic_] and Iron" (_Mineralogia Cornubiensis_, +p. 2). + +It is conceivable that gold could be found in large enough pieces to +have had general use in pre-historic times, without fusion; but copper, +which was also in use, must have been smelted, and therefore we must +assume a considerable development of human knowledge on the subject +prior to any human record. Such incidental mention as exists after +record begins does not, of course, extend to the beginning of any +particular branch of the art--in fact, special arts obviously existed +long before such mention, and down to the complete survey of the state +of the art by Agricola our dates are necessarily "prior to" some first +mention in literature, or "prior to" the known period of existing +remains of metallurgical operations. The scant Egyptian records, the +Scriptures, and the Shoo King give a little insight prior to 1000 B.C. +The more extensive Greek literature of about the 5th to the 3rd +centuries B.C., together with the remains of Greek mines, furnish +another datum point of view, and the Roman and Greek writers at the +beginning of the Christian era give a still larger view. After them our +next step is to the Monk Theophilus and the Alchemists, from the 12th to +the 14th centuries. Finally, the awakening of learning at the end of the +15th and the beginning of the 16th centuries, enables us for the first +time to see practically all that was known. The wealth of literature +which exists subsequent to this latter time makes history thereafter a +matter of some precision, but it is not included in this undertaking. +Considering the great part that the metals have played in civilization, +it is astonishing what a minute amount of information is available on +metallurgy. Either the ancient metallurgists were secretive as to their +art, or the ancient authors despised such common things, or, as is +equally probable, the very partial preservation of ancient literature, +by painful transcription over a score of centuries, served only for +those works of more general interest. In any event, if all the direct or +indirect material on metallurgy prior to the 15th century were compiled, +it would not fill 40 pages such as these. + +It may be of service to give a tabular summary indicating approximately +the time when evidence of particular operations appear on the historical +horizon: + + Gold washed from alluvial Prior to recorded + civilization + + Copper reduced from ores by smelting Prior to recorded + civilization + + Bitumen mined and used Prior to recorded + civilization + + Tin reduced from ores by smelting Prior to 3500 B.C. + + Bronze made Prior to 3500 B.C. + + Iron reduced from ores by smelting Prior to 3500 B.C. + + Soda mined and used Prior to 3500 B.C. + + Gold reduced from ores by concentration Prior to 2500 B.C. + + Silver reduced from ores by smelting Prior to 2000 B.C. + + Lead reduced from ores by smelting Prior to 2000 B.C. + (perhaps prior + to 3500 B.C.) + + Silver parted from lead by cupellation Prior to 2000 B.C. + + Bellows used in furnaces Prior to 1500 B.C. + + Steel produced Prior to 1000 B.C. + + Base metals separated from ores by water Prior to 500 B.C. + concentration + + Gold refined by cupellation Prior to 500 B.C. + + Sulphide ores smelted for lead Prior to 500 B.C. + + Mercury reduced from ores by (?) Prior to 400 B.C. + + White-lead made with vinegar Prior to 300 B.C. + + Touchstone known for determining gold and silver Prior to 300 B.C. + fineness + + Quicksilver reduced from ore by distillation Prior to Christian Era + + Silver parted from gold by cementation with salt Prior to " " + + Brass made by cementation of copper and calamine Prior to " " + + Zinc oxides obtained from furnace fumes by Prior to " " + construction of dust chambers + + Antimony reduced from ores by smelting (accidental) Prior to " " + + Gold recovered by amalgamation Prior to " " + + Refining of copper by repeated fusion Prior to " " + + Sulphide ores smelted for copper Prior to " " + + Vitriol (blue and green) made Prior to " " + + Alum made Prior to " " + + Copper refined by oxidation and poling Prior to 1200 A.D. + + Gold parted from copper by cupelling with lead Prior to 1200 A.D. + + Gold parted from silver by fusion with sulphur Prior to 1200 A.D. + + Manufacture of nitric acid and _aqua regia_ Prior to 1400 A.D. + + Gold parted from silver by nitric acid Prior to 1400 A.D. + + Gold parted from silver with antimony sulphide Prior to 1500 A.D. + + Gold parted from copper with sulphur Prior to 1500 A.D. + + Silver parted from iron with antimony sulphide Prior to 1500 A.D. + + First text book on assaying Prior to 1500 A.D. + + Silver recovered from ores by amalgamation Prior to 1500 A.D. + + Separation of silver from copper by liquation Prior to 1540 A.D. + + Cobalt and manganese used for pigments Prior to 1540 A.D. + + Roasting copper ores prior to smelting Prior to 1550 A.D. + + Stamp-mill used Prior to 1550 A.D. + + Bismuth reduced from ore Prior to 1550 A.D. + + Zinc reduced from ore (accidental) Prior to 1550 A.D. + +Further, we believe it desirable to sketch at the outset the development +of metallurgical appliances as a whole, leaving the details to special +footnotes; otherwise a comprehensive view of the development of such +devices is difficult to grasp. + +We can outline the character of metallurgical appliances at various +periods in a few words. It is possible to set up a description of the +imaginary beginning of the "bronze age" prior to recorded civilization, +starting with the savage who accidentally built a fire on top of some +easily reducible ore, and discovered metal in the ashes, etc.; but as +this method has been pursued times out of number to no particular +purpose, we will confine ourselves to a summary of such facts as we can +assemble. "Founders' hoards" of the bronze age are scattered over +Western Europe, and indicate that smelting was done in shallow pits with +charcoal. With the Egyptians we find occasional inscriptions showing +small furnaces with forced draught, in early cases with a blow-pipe, but +later--about 1500 B.C.--with bellows also. The crucible was apparently +used by the Egyptians in secondary melting, such remains at Mt. Sinai +probably dating before 2000 B.C. With the advent of the Prophets, and +the first Greek literature--9th to 7th century B.C.--we find frequent +references to bellows. The remains of smelting appliances at Mt. Laurion +(500-300 B.C.) do not indicate much advance over the primitive hearth; +however, at this locality we do find evidence of the ability to separate +minerals by specific gravity, by washing crushed ore over inclined +surfaces with a sort of buddle attachment. Stone grinding-mills were +used to crush ore from the earliest times of Mt. Laurion down to the +Middle Ages. About the beginning of the Christian era the writings of +Diodorus, Strabo, Dioscorides, and Pliny indicate considerable advance +in appliances. Strabo describes high stacks to carry off lead fumes; +Dioscorides explains a furnace with a dust-chamber to catch _pompholyx_ +(zinc oxide); Pliny refers to the upper and lower crucibles (a +forehearth) and to the pillars and arches of the furnaces. From all of +their descriptions we may conclude that the furnaces had then reached +some size, and were, of course, equipped with bellows. At this time +sulphide copper and lead ores were smelted; but as to fluxes, except +lead for silver, and lead and soda for gold, we have practically no +mention. Charcoal was the universal fuel for smelting down to the 18th +century. Both Dioscorides and Pliny describe a distillation apparatus +used to recover quicksilver. A formidable list of mineral products and +metal alloys in use, indicate in themselves considerable apparatus, of +the details of which we have no indication; in the main these products +were lead sulphide, sulphate, and oxide (red-lead and litharge); zinc +oxide; iron sulphide, oxide and sulphate; arsenic and antimony +sulphides; mercury sulphide, sulphur, bitumen, soda, alum and potash; +and of the alloys, bronze, brass, pewter, electrum and steel. + +From this period to the period of the awakening of learning our only +light is an occasional gleam from Theophilus and the Alchemists. The +former gave a more detailed description of metallurgical appliances than +had been done before, but there is little vital change apparent from the +apparatus of Roman times. The Alchemists gave a great stimulus to +industrial chemistry in the discovery of the mineral acids, and +described distillation apparatus of approximately modern form. + +The next period--the Renaissance--is one in which our descriptions are +for the first time satisfactory, and a discussion would be but a review +of _De Re Metallica_. + +[2] See footnote 2, p. 267, on verbs used for roasting. + +[3] Agricola has here either forgotten to take into account his +three-palm-thick furnace walls, which will make the length of this long +wall sixty-one feet, or else he has included this foot and a half in +each case in the six-foot distance between the furnaces, so that the +actual clear space is only four and a half feet between the furnace with +four feet on the ends. + +[4] The paucity of terms in Latin for describing structural members, and +the consequent repetition of "beam" (_trabs_), "timber" (_tignum_), +"billet" (_tigillum_), "pole" (_asser_), with such modifications as +small, large, and transverse, and with long explanatory clauses showing +their location, renders the original very difficult to follow. We have, +therefore, introduced such terms as "posts," "tie-beams," "sweeps," +"levers," "rafters," "sills," "moulding," "braces," "cleats," +"supports," etc., as the context demands. + +[5] This set of rafters appears to start from the longitudinal beam. + +[6] Devices for creating an air current must be of very old invention, +for it is impossible to conceive of anything but the crudest melting of +a few simple ores without some forced draft. Wilkinson (The Ancient +Egyptians, II, p. 316) gives a copy of an illustration of a foot-bellows +from a tomb of the time of Thotmes III. (1500 B.C.). The rest of the +world therefore, probably obtained them from the Egyptians. They are +mentioned frequently in the Bible, the most pointed reference to +metallurgical purposes being Jeremiah (VI, 29): "The bellows are burned, +the lead is consumed in the fire; the founder melteth in vain; for the +wicked are not plucked away." Strabo (VII, 3) states that Ephorus +ascribed the invention of bellows to Anacharsis--a Thracian prince of +about 600 B.C. + +[7] This whole arrangement could be summarized by the word "hinge." + +[8] The rim of this wheel is obviously made of segments fixed in two +layers; the "disc" meaning the aggregate of segments on either side of +the wheel. + +[9] It has not been considered necessary to introduce the modern term +_twyer_ in these descriptions, as the literal rendering is sufficiently +clear. + +[10] _Ferruminata_. These accretions are practically always near the +hearth, and would correspond to English "sows," and therefore that term +has been adopted. It will be noted that, like most modern metallurgists, +Agricola offers no method for treating them. Pliny (XXXIV, 37) describes +a "sow," and uses the verb _ferruminare_ (to weld or solder): "Some say +that in the furnace there are certain masses of stone which become +soldered together, and that the copper fuses around it, the mass not +becoming liquid unless it is transferred to another furnace; it thus +forms a sort of knot, as it were, of the metal." + +[11] What are known in English as "crucible," "furnace well," +"forehearth," "dipping-pot," "tapping-pot," "receiving-pot," etc., are +in the text all _catinus_, _i.e._, crucible. For easier reading, +however, we have assigned the names indicated in the context. + +[12] _Panes ex pyrite conflati_. While the term _matte_ would cover most +cases where this expression appears, and in many cases would be more +expressive to the modern reader, yet there are instances where the +expression as it stands indicates its particular origin, and it has +been, therefore, considered advisable to adhere to the literal +rendering. + +[13] _Molybdaena_. See note 37, p. 476. It was the saturated furnace +bottoms from cupellation. + +[14] The four elements were earth, air, fire, and water. + +[15] "Stones which easily melt in the fire." Nowhere in _De Re +Metallica_ does the author explain these substances. However in the +_Interpretatio_ (p. 465) he gives three genera or orders with their +German equivalents, as follows:--"_Lapides qui igni liquescunt primi +generis,--Schöne flüsse; secundi,--flüsse zum schmeltzen flock quertze; +tertii,--quertze oder kiselstein."_ We confess our inability to make +certain of most of the substances comprised in the first and second +orders. We consider they were in part fluor-spar, and in any event the +third order embraced varieties of quartz, flint, and silicious material +generally. As the matter is of importance from a metallurgical point of +view, we reproduce at some length Agricola's own statements on the +subject from _Bermannus_ and _De Natura Fossilium_. In the latter (p. +268) he states: "Finally there now remain those stones which I call +'stones which easily melt in the fire,' because when thrown into hot +furnaces they flow (_fluunt_). There are three orders (_genera_) of +these. The first resembles the transparent gems; the second is not +similar, and is generally not translucent; it is translucent in some +part, and in rare instances altogether translucent. The first is +sparingly found in silver and other mines; the second abounds in veins +of its own. The third genus is the material from which glass is made, +although it can also be made out of the other two. The stones of the +first order are not only transparent, but are also resplendent, and have +the colours of gems, for some resemble crystal, others emerald, +heliotrope, lapis lazuli, amethyst, sapphire, ruby, _chrysolithus_, +_morion_ (cairngorm?), and other gems, but they differ from them in +hardness.... To the first genus belongs the _lapis alabandicus_ (modern +albandite?), if indeed it was different from the alabandic carbuncle. It +can be melted, according to Pliny, in the fire, and fused for the +preparation of glass. It is black, but verging upon purple. It comes +from Caria, near Alabanda, and from Miletus in the same province. The +second order of stones does not show a great variety of colours, and +seldom beautiful ones, for it is generally white, whitish, greyish, or +yellowish. Because these (stones) very readily melt in the fire, they +are added to the ores from which the metals are smelted. The small +stones found in veins, veinlets, and the spaces between the veins, of +the highest peaks of the Sudetic range (_Suditorum montium_), belong +partly to this genus and partly to the first. They differ in size, being +large and small; and in shape, some being round or angular or pointed; +in colour they are black or ash-grey, or yellow, or purple, or violet, +or iron colour. All of these are lacking in metals. Neither do the +little stones contain any metals which are usually found in the streams +where gold dust is collected by washing.... In the rivers where are +collected the small stones from which tin is smelted, there are three +genera of small stones to be found, all somewhat rounded and of very +light weight, and devoid of all metals. The largest are black, both on +the outside and inside, smooth and brilliant like a mirror; the +medium-sized are either bluish black or ash-grey; the smallest are of a +yellowish colour, somewhat like a silkworm. But because both the former +and the latter stones are devoid of metals, and fly to pieces under the +blows of the hammer, we classify them as sand or gravel. Glass is made +from the stones of the third order, and particularly from sand. For when +this is thrown into the heated furnace it is melted by the fire.... This +kind of stone is either found in its own veins, which are occasionally +very wide, or else scattered through the mines. It is less hard than +flint, on account of which no fire can be struck from it. It is not +transparent, but it is of many colours--that is to say, white, +yellowish, ash-grey, brown, black, green, blue, reddish or red. This +genus of stones occurs here and there in mountainous regions, on banks +of rivers, and in the fields. Those which are black right through to the +interior, and not merely on the surface, are more rare; and very +frequently one coloured vein is intersected by another of a different +colour--for instance, a white one by a red one; the green is often +spotted with white, the ash-grey with black, the white with crimson. +Fragments of these stones are frequently found on the surface of the +earth, and in the running water they become polished by rubbing against +stones of their own or of another genus. In this way, likewise, +fragments of rocks are not infrequently shaped into spherical forms.... +This stone is put to many uses; the streets are paved with it, whatever +its colour; the blue variety is added to the ash of pines for making +those other ashes which are used by wool-dyers. The white variety is +burned, ground, and sifted, and from this they make the sand out of +which glass is made. The whiter the sand is, the more useful it is." + +Perusal of the following from _Bermannus_ (p. 458) can leave little +doubt as to the first or second order being in part fluor-spar. Agricola +derived the name _fluores_ from _fluo_ "to flow," and we in turn obtain +"fluorite," or "fluorspar," from Agricola. "_Bermannus_.--These stones +are similar to gems, but less hard. Allow me to explain word for word. +Our miners call them _fluores_, not inappropriately to my mind, for by +the heat of fire, like ice in the sun, they liquefy and flow away. They +are of varied and bright colours. _Naevius_.--Theophrastus says of them +that they are made by a conflux in the earth. These red _fluores_, to +employ the words just used by you, are the ruby silver which you showed +us before. _Bermannus_.--At the first glance it appears so, although it +is not infrequently translucent. _Naevius_.--Then they are rubies? +_Bermannus_.--Not that either. _Naevius_.--In what way, then, can they +be distinguished from rubies? _Bermannus_.--Chiefly by this sign, that +they glitter more feebly when translucent. Those which are not +translucent may be distinguished from rubies. Moreover, _fluores_ of all +kinds melt when they are subject to the first fire; rubies do not melt +in fire. _Naevius_.--You distinguish well. _Bermannus_.--You see the +other kind, of a paler purple colour? _Naevius_.--They appear to be an +inferior kind of amethyst, such as are found in many places in Bohemia. +_Bermannus_.--Indeed, they are not very dissimilar, therefore the common +people who do not know amethysts well, set them in rings for gems, and +they are easily sold. The third kind, as you see here, is white. +_Naevius_.--I should have thought it a crystal. _Bermannus_.--A fourth +is a yellow colour, a fifth ash colour, a sixth blackish. Some are +violet, some green, others gold-coloured. _Anton_.--What is the use of +_fluores_? _Bermannus_.--They are wont to be made use of when metals are +smelted, as they cause the material in the fire to be much more fluid, +exactly like a kind of stone which we said is made from pyrites (matte); +it is, indeed, made not far from here, at Breitenbrunn, which is near +Schwarzenberg. Moreover, from _fluores_ they can make colours which +artists use." + +[16] _Stannum_. (_Interpretatio_,--_werck_, modern _werk_). This term +has been rendered throughout as "silver-lead" or "silver-lead alloy." It +was the argentiferous lead suitable for cupellation. Agricola, in using +it in this sense, was no doubt following his interpretation of its use +by Pliny. Further remarks upon this subject will be found in note 33, p. +473. + +[17] _Expirare_,--to exhale or blow out. + +[18] _Rhetos_. The ancient Rhaetia comprised not only the greater part +of Tyrol, but also parts of Switzerland and Lombardy. The mining section +was, however, in Tyrol. + +[19] _Noricum_ was a region south of the Danube, embracing not only +modern Styria, but also parts of Austria, Salzberg, and Carinthia. + +[20] One _drachma_ of gold to a _centumpondium_ would be (if we assume +these were Roman weights) 3 ozs. 1 dwt. Troy per short ton. One-half +_uncia_ of silver would be 12 ozs. 3 dwts. per short ton. + +[21] For discussion of these fluxes see note page 232. + +[22] _Carni_. Probably the people of modern Austrian Carniola, which +lies south of Styria and west of Croatia. + +[23] HISTORICAL NOTE ON SMELTING LEAD AND SILVER.--The history of lead +and silver smelting is by no means a sequent array of exact facts. With +one possible exception, lead does not appear upon the historical horizon +until long after silver, and yet their metallurgy is so inextricably +mixed that neither can be considered wholly by itself. As silver does +not occur native in any such quantities as would have supplied the +amounts possessed by the Ancients, we must, therefore, assume its +reduction by either (1) intricate chemical processes, (2) amalgamation, +(3) reduction with copper, (4) reduction with lead. It is impossible to +conceive of the first with the ancient knowledge of chemistry; the +second (see note 12, p. 297) does not appear to have been known until +after Roman times; in any event, quicksilver appears only at about 400 +B.C. The third was impossible, as the parting of silver from copper +without lead involves metallurgy only possible during the last century. +Therefore, one is driven to the conclusion that the fourth case +obtained, and that the lead must have been known practically +contemporaneously with silver. There is a leaden figure exhibited in the +British Museum among the articles recovered from the Temple of Osiris at +Abydos, and considered to be of the Archaic period--prior to 3800 B.C. +The earliest known Egyptian silver appears to be a necklace of beads, +supposed to be of the XII. Dynasty (2400 B.C.), which is described in +the 17th Memoir, Egyptian Exploration Fund (London, 1898, p. 22). With +this exception of the above-mentioned lead specimen, silver articles +antedate positive evidence of lead by nearly a millennium, and if we +assume lead as a necessary factor in silver production, we must conclude +it was known long prior to any direct (except the above solitary +possibility) evidence of lead itself. Further, if we are to conclude its +necessary association with silver, we must assume a knowledge of +cupellation for the parting of the two metals. Lead is mentioned in 1500 +B.C. among the spoil captured by Thotmes III. Leaden objects have +frequently been found in Egyptian tombs as early as Rameses III. (1200 +B.C.). The statement is made by Pulsifer (Notes for a History of Lead, +New York 1888, p. 146) that Egyptian pottery was glazed with lead. We +have been unable to find any confirmation of this. It may be noted, +incidentally, that lead is not included in the metals of the "Tribute of +Yü" in the Shoo King (The Chinese Classics, 2500 B.C.?), although silver +is so included. + +After 1200 or 1300 B.C. evidences of the use of lead become frequent. +Moses (Numbers XXXI, 22-23) directs the Israelites with regard to their +plunder from the Midianites (1300 B.C.): "Only the gold and the silver, +the brass [_sic_], the iron, the tin, and the lead. Everything that may +abide the fire, ye shall make it go through the fire, and it shall be +clean; nevertheless, it shall be purified with the water of separation, +and all that abideth not the fire ye shall make go through the water." +Numerous other references occur in the Scriptures (Psalms XII, 6; +Proverbs XVII, 3; XXV, 4; etc.), one of the most pointed from a +metallurgical point of view being that of Jeremiah (600 B.C.), who says +(VI, 29-30): "The bellows are burned, the lead is consumed of the fire; +the founder melteth in vain; for the wicked are not plucked away. +Reprobate silver shall men call them because the Lord hath rejected +them." From the number of his metaphors in metallurgical terms we may +well conclude that Jeremiah was of considerable metallurgical +experience, which may account for his critical tenor of mind. These +Biblical references all point to a knowledge of separating silver and +lead. Homer mentions lead (Iliad XXIV, 109), and it has been found in +the remains of ancient Troy and Mycenae (H. Schliemann, "Troy and its +Remains," London, 1875, and "Mycenae," New York, 1877). Both Herodotus +(I, 186) and Diodorus (II, 1) speak of the lead used to fix iron clamps +in the stone bridge of Nitocris (600 B.C.) at Babylon. + +Our best evidence of ancient lead-silver metallurgy is the result of the +studies at Mt. Laurion by Edouard Ardaillon (_Mines du Laurion dans +l'Antiquité_, Paris, 1897). Here the very extensive old workings and the +slag heaps testify to the greatest activity. The re-opening of the mines +in recent years by a French Company has well demonstrated their +technical character, and the frequent mention in Greek History easily +determines their date. These deposits of argentiferous galena were +extensively worked before 500 B.C. and while the evidence of +concentration methods is ample, there is but little remaining of the +ancient smelters. Enough, however, remains to demonstrate that the +galena was smelted in small furnaces at low heat, with forced draught, +and that it was subsequently cupelled. In order to reduce the sulphides +the ancient smelters apparently depended upon partial roasting in the +furnace at a preliminary period in reduction, or else upon the +ferruginous character of the ore, or upon both. See notes p. 27 and p. +265. Theognis (6th century B.C.) and Hippocrates (5th century B.C.) are +frequently referred to as mentioning the refining of gold with lead; an +inspection of the passages fails to corroborate the importance which has +been laid upon them. Among literary evidences upon lead metallurgy of +later date, Theophrastus (300 B.C.) describes the making of white-lead +with lead plates and vinegar. Diodorus Siculus (1st century B.C.), in +his well-known quotation from Agatharchides (2nd century B.C.) with +regard to gold mining and treatment in Egypt, describes the refining of +gold with lead. (See note 8, p. 279.) Strabo (63 B.C.-24 A.D.) says +(III, 2, 8): "The furnaces for silver are constructed lofty in order +that the vapour, which is dense and pestilent, may be raised and carried +off." And again (III, 2, 10), in quoting from Polybius (204-125 B.C.): +"Polybius, speaking of the silver mines of New Carthage, tells us that +they are extremely large, distant from the city about 20 stadia, and +occupy a circuit of 400 stadia; that there are 40,000 men regularly +engaged in them, and that they yield daily to the Roman people (a +revenue of) 25,000 drachmae. The rest of the process I pass over, as it +is too long; but as for the silver ore collected, he tells us that it is +broken up and sifted through sieves over water; that what remains is to +be again broken, and the water having been strained off it is to be +sifted and broken a third time. The dregs which remain after the fifth +time are to be melted, and the lead being poured off, the silver is +obtained pure. These silver mines still exist; however, they are no +longer the property of the State, neither these nor those elsewhere, but +are possessed by private individuals. The gold mines, on the contrary, +nearly all belong to the State. Both at Castlon and other places there +are singular lead mines worked. They contain a small proportion of +silver, but not sufficient to pay for the expense of refining" +(Hamilton's Trans.). Dioscorides (1st century A.D.), among his +medicines, describes several varieties of litharge, their origin, and +the manner of making white-lead (see on pp. 465, 440), but he gives no +very tangible information on lead smelting. Pliny, at the same period in +speaking of silver, (XXXIII, 31), says: "After this we speak of silver, +the next folly. Silver is only found in shafts, there being no +indications like shining particles as in the case of gold. This earth is +sometimes red, sometimes of an ashy colour. It is impossible to melt it +except with lead ore (_vena plumbi_), called _galena_, which is +generally found next to silver veins. And this the same agency of fire +separates part into lead, which floats on the silver like oil on water." +(We have transferred lead and silver in this last sentence, otherwise it +means nothing.) Also (XXXIV, 47) he says: "There are two different +sources of lead, it being smelted from its own ore, whence it comes +without the admixture of any other substance, or else from an ore which +contains it in common with silver. The metal, which flows liquid at the +first melting in the furnace, is called _stannum_ that at the second +melting is silver; that which remains in the furnace is _galena_, which +is added to a third part of the ore. This being again melted, produces +lead with a deduction of two-ninths." We have, despite some grammatical +objections, rendered this passage quite differently from other +translators, none of whom have apparently had any knowledge of +metallurgy; and we will not, therefore, take the several pages of space +necessary to refute their extraordinary and unnecessary hypotheses. From +a metallurgical point of view, two facts must be kept in mind,--first, +that _galena_ in this instance was the same substance as _molybdaena_, +and they were both either a variety of litharge or of lead carbonates; +second, that the _stannum_ of the Ancients was silver-lead alloy. +Therefore, the metallurgy of this paragraph becomes a simple melting of +an argentiferous lead ore, its subsequent cupellation, with a return of +the litharge to the furnace. Pliny goes into considerable detail as to +varieties of litharge, for further notes upon which see p. 466. The +Romans were most active lead-silver miners, not only in Spain, but also +in Britain. There are scores of lead pigs of the Roman era in various +English museums, many marked "_ex argent_." Bruce (The Roman Wall, +London, 1852, p. 432) describes some Roman lead furnaces in Cumberland +where the draught was secured by driving a tapering tunnel into the +hills. The Roman lead slag ran high in metal, and formed a basis for +quite an industry in England in the early 18th century (Hunt, British +Mining, London, 1887, p. 26, etc.). There is nothing in mediæval +literature which carries us further with lead metallurgy than the +knowledge displayed by Pliny, until we arrive at Agricola's period. The +history of cupellation is specially dealt with in note on p. 465. + +[25] _Cadmia_. In the German Translation this is given as _kobelt_. It +would be of uncertain character, but no doubt partially furnace +calamine. (See note on p. 112.) + +[26] _Pompholyx_. (_Interpretatio_ gives the German as _Weisser hütten +rauch als ober dem garherde und ober dem kupfer ofen_). This was the +impure protoxide of zinc deposited in the furnace outlets, and is modern +"tutty." The ancient products, no doubt, contained arsenical oxides as +well. It was well known to the Ancients, and used extensively for +medicinal purposes, they dividing it into two species--_pompholyx_ and +_spodos_. The first adequate description is by Dioscorides (V, 46): +"_Pompholyx_ differs from _spodos_ in species, not in genus. For +_spodos_ is blacker, and is often heavier, full of straws and hairs, +like the refuse that is swept from the floors of copper smelters. But +_pompholyx_ is fatty, unctuous, white and light enough to fly in the +air. Of this there are two kinds--the one inclines to sky blue and is +unctuous; the other is exceedingly white, and is extremely light. White +_pompholyx_ is made every time that the artificer, in the preparation +and perfecting of copper (brass?) sprinkles powdered _cadmia_ upon it to +make it more perfect, for the soot which rises being very fine becomes +_pompholyx_. Other _pompholyx_ is made, not only in working copper +(brass?), but is also made from _cadmia_ by continually blowing with +bellows. The manner of doing it is as follows:--The furnace is +constructed in a two-storied building, and there is a medium-sized +aperture opening to the upper chamber; the building wall nearest the +furnace is pierced with a small opening to admit the nozzle of the +bellows. The building must have a fair-sized door for the artificer to +pass in and out. Another small building must adjoin this, in which are +the bellows and the man who works them. Then the charcoal in the furnace +is lighted, and the artificer continually throws broken bits of _cadmia_ +from the place above the furnace, whilst his assistant, who is below, +throws in charcoals, until all of the _cadmia_ inside is consumed. By +this means the finest and lightest part of the stuff flies up with the +smoke to the upper chamber, and adheres to the walls of the roof. The +substance which is thus formed has at first the appearance of bubbles on +water, afterward increasing in size, it looks like skeins of wool. The +heaviest parts settle in the bottom, while some fall over and around the +furnaces, and some lie on the floor of the building. This latter part is +considered inferior, as it contains a lot of earth and becomes full of +dirt." + +Pliny (XXXIV, 33) appears somewhat confused as to the difference between +the two species: "That which is called _pompholyx_ and _spodos_ is found +in the copper-smelting furnaces, the difference between them being that +_pompholyx_ is separated by washing, while _spodos_ is not washed. Some +have called that which is white and very light _pompholyx_, and it is +the soot of copper and _cadmia_; whereas _spodos_ is darker and heavier. +It is scraped from the walls of the furnace, and is mixed with particles +of metal, and sometimes with charcoal." (XXXIV, 34.) "The Cyprian +_spodos_ is the best. It is formed by fusing _cadmia_ with copper ore. +This being the lightest part of the metal, it flies up in the fumes from +the furnace, and adheres to the roof, being distinguished from the soot +by its whiteness. That which is less white is immature from the furnace, +and it is this which some call '_pompholyx_.'" Agricola (_De Natura +Fossilium_, p. 350) traverses much the same ground as the authors +previously quoted, and especially recommends the _pompholyx_ produced +when making brass by melting alternate layers of copper and calamine +(_cadmia fossilis_). + +[27] _Oleo, ex fece vini sicca confecto_. This oil, made from argol, is +probably the same substance mentioned a few lines further on as "wine," +distilled by heating argol in a retort. Still further on, salt made from +argol is mentioned. It must be borne in mind that this argol was crude +tartrates from wine vats, and probably contained a good deal of organic +matter. Heating argol sufficiently would form potash, but that the +distillation product could be anything effective it is difficult to see. + +[28] _Aqua valens_. No doubt mainly nitric acid, the preparation of +which is explained at length in Book X, p. 439. + +[29] _Quod cum ignis consumit non modo una cum eo, quae ipsius stibii +vis est, aliqua auri particula, sed etiam argenti, si cum auro fuerit +permistum, consumitur._ The meaning is by no means clear. On p. 451 is +set out the old method of parting silver from gold with antimony +sulphide, of which this may be a variation. The silver combines with +sulphur, and the reduced antimony forms an alloy with the gold. The +added iron and copper would also combine with the sulphur from the +antimony sulphide, and no doubt assist by increasing the amount of free +collecting agent and by increasing the volume of the matte. (See note +17, p. 451.) + +[30] There follow eight different methods of treating crude bullion or +rich concentrates. In a general way three methods are involved,--1st, +reduction with lead or antimony, and cupellation; 2nd, reduction with +silver, and separation with nitric acid; 3rd, reduction with lead and +silver, followed by cupellation and parting with nitric acid. The use of +sulphur or antimony sulphide would tend to part out a certain amount of +silver, and thus obtain fairly pure bullion upon cupellation. But the +introduction of copper could only result deleteriously, except that it +is usually accompanied by sulphur in some form, and would thus probably +pass off harmlessly as a matte carrying silver. (See note 33 below.) + +[31] It is not very clear where this lead comes from. Should it be +antimony? The German translation gives this as "silver." + +[32] These powders are described in Book VII., p. 236. It is difficult +to say which the second really is. There are numbers of such recipes in +the _Probierbüchlein_ (see Appendix B), with which a portion of these +are identical. + +[33] A variety of methods are involved in this paragraph: 1st, crude +gold ore is smelted direct; 2nd, gold concentrates are smelted in a lead +bath with some addition of iron--which would simply matte off--the lead +bullion being cupelled; 3rd, roasted and unroasted pyrites and _cadmia_ +(probably blende, cobalt, arsenic, etc.) are melted into a matte; this +matte is repeatedly roasted, and then re-melted in a lead bath; 4th, if +the material "flies out of the furnace" it is briquetted with iron ore +and lime, and the briquettes smelted with copper matte. Three products +result: (_a_) slag; (_b_) matte; (_c_) copper-gold-silver alloy. The +matte is roasted, re-smelted with lead, and no doubt a button obtained, +and further matte. The process from this point is not clear. It appears +that the copper bullion is melted with lead, and normally this product +would be taken to the liquation furnace, but from the text it would +appear that the lead-copper bullion was melted again with iron ore and +pyrites, in which case some of the copper would be turned into the +matte, and the lead alloy would be richer in gold and silver. + +HISTORICAL NOTE ON GOLD.--There is ample evidence of gold being used for +ornamental purposes prior to any human record. The occurrence of large +quantities of gold in native form, and the possibility of working it +cold, did not necessitate any particular metallurgical ingenuity. The +earliest indications of metallurgical work are, of course, among the +Egyptians, the method of washing being figured as early as the monuments +of the IV Dynasty (prior to 3800 B.C.). There are in the British Museum +two stelae of the XII Dynasty (2400 B.C.) (144 Bay 1 and 145 Bay 6) +relating to officers who had to do with gold mining in Nubia, and upon +one there are references to working what appears to be ore. If this be +true, it is the earliest reference to this subject. The Papyrus map +(1500 B.C.) of a gold mine, in the Turin Museum (see note 16, p. 129), +probably refers to a quartz mine. Of literary evidences there is +frequent mention of refining gold and passing it through the fire in the +Books of Moses, arts no doubt learned from the Egyptians. As to working +gold, ore as distinguished from alluvial, we have nothing very tangible, +unless it be the stelae above, until the description of Egyptian gold +mining by Agatharchides (see note 8, p. 279). This geographer, of about +the 2nd century B.C., describes very clearly indeed the mining, +crushing, and concentration of ore and the refining of the concentrates +in crucibles with lead, salt, and barley bran. We may mention in passing +that Theognis (6th Century B.C.) is often quoted as mentioning the +refining of gold with lead, but we do not believe that the passage in +question (1101): "But having been put to the test and being rubbed +beside (or against) lead as being refined gold, you will be fair," etc.; +or much the same statement again (418) will stand much metallurgical +interpretation. In any event, the myriads of metaphorical references to +fining and purity of gold in the earliest shreds of literature do not +carry us much further than do those of Shakespeare or Milton. Vitruvius +and Pliny mention the recovery or refining of gold with mercury (see +note 12, p. 297 on Amalgamation); and it appears to us that gold was +parted from silver by cementation with salt prior to the Christian era. +We first find mention of parting with sulphur in the 12th century, with +nitric acid prior to the 14th century, by antimony sulphide prior to the +15th century, and by cementation with nitre by Agricola. (See historical +note on parting gold and silver, p. 458.) The first mention of parting +gold from copper occurs in the early 16th century (see note 24, p. 462). +The first comprehensive description of gold metallurgy in all its +branches is in _De Re Metallica_. + +[34] _Rudis_ silver comprised all fairly pure silver ores, such as +silver sulphides, chlorides, arsenides, etc. This is more fully +discussed in note 6, p. 108. + +[35] _Evolent_,--volatilize? + +[36] _Lapidis plumbarii facile liquescentis_. The German Translation +gives _glantz_, _i.e._, Galena, and the _Interpretatio_ also gives +_glantz_ for _lapis plumbarius_. We are, however, uncertain whether this +"easily melting" material is galena or some other lead ore. + +[37] _Molybdaena_ is usually hearth-lead in _De Re Metallica_, but the +German translation in this instance uses _pleyertz_, lead ore. From the +context it would not appear to mean hearth-lead--saturated bottoms of +cupellation furnaces--for such material would not contain appreciable +silver. Agricola does confuse what are obviously lead carbonates with +his other _molybdaena_ (see note 37, p. 476). + +[38] The term _cadmia_ is used in this paragraph without the usual +definition. Whether it was _cadmia fornacis_ (furnace accretions) or +_cadmia metallica_ (cobalt-arsenic-blende mixture) is uncertain. We +believe it to be the former. + +[39] _Ramentum si lotura ex argento rudi_. This expression is generally +used by the author to indicate concentrates, but it is possible that in +this sentence it means the tailings after washing rich silver minerals, +because the treatment of the _rudis_ silver has been already discussed +above. + +[40] _Ustum_. This might be rendered "burnt." In any event, it seems +that the material is sintered. + +[41] _Aes purum sive proprius ei color insederit, sive chrysocolla vel +caeruleo fuerit tinctum, et rude plumbei coloris, aut fusci, aut nigri._ +There are six copper minerals mentioned in this sentence, and from our +study of Agricola's _De Natura Fossilium_ we hazard the +following:--_Proprius ei color insederit_,--"its own colour,"--probably +cuprite or "ruby copper." _Tinctum chrysocolla_--partly the modern +mineral of that name and partly malachite. _Tinctum caeruleo_, partly +azurite and partly other blue copper minerals. _Rude plumbei +coloris_,--"lead coloured,"--was certainly chalcocite (copper glance). +We are uncertain of _fusci aut nigri_, but they were probably alteration +products. For further discussion see note on p. 109. + +[42] HISTORICAL NOTE ON COPPER SMELTING.--The discoverer of the +reduction of copper by fusion, and his method, like the discoverer of +tin and iron, will never be known, because he lived long before humanity +began to make records of its discoveries and doings. Moreover, as +different races passed independently and at different times through the +so-called "Bronze Age," there may have been several independent +discoverers. Upon the metallurgy of pre-historic man we have some +evidence in the many "founders' hoards" or "smelters' hoards" of the +Bronze Age which have been found, and they indicate a simple shallow pit +in the ground into which the ore was placed, underlaid with charcoal. +Rude round copper cakes eight to ten inches in diameter resulted from +the cooling of the metal in the bottom of the pit. Analyses of such +Bronze Age copper by Professor Gowland and others show a small +percentage of sulphur, and this is possible only by smelting oxidized +ores. Copper objects appear in the pre-historic remains in Egypt, are +common throughout the first three dynasties, and bronze articles have +been found as early as the IV Dynasty (from 3800 to 4700 B.C., according +to the authority adopted). The question of the origin of this bronze, +whether from ores containing copper and tin or by alloying the two +metals, is one of wide difference of opinion, and we further discuss the +question in note 53, p. 411, under Tin. It is also interesting to note +that the crucible is the emblem of copper in the hieroglyphics. The +earliest source of Egyptian copper was probably the Sinai Peninsula, +where there are reliefs as early as Seneferu (about 3700 B.C.), +indicating that he worked the copper mines. Various other evidences +exist of active copper mining prior to 2500 B.C. (Petrie, Researches in +Sinai, London, 1906, p. 51, etc.). The finding of crucibles here would +indicate some form of refining. Our knowledge of Egyptian copper +metallurgy is limited to deductions from their products, to a few +pictures of crude furnaces and bellows, and to the minor remains on the +Sinai Peninsula; none of the pictures were, so far as we are aware, +prior to 2300 B.C., but they indicate a considerable advance over the +crude hearth, for they depict small furnaces with forced draught--first +a blow-pipe, and in the XVIII Dynasty (about 1500 B.C.) the bellows +appear. Many copper articles have been found scattered over the Eastern +Mediterranean and Asia Minor of pre-Mycenaean Age, some probably as +early as 3000 B.C. This metal is mentioned in the "Tribute of Yü" in the +Shoo King (2500 B.C.?); but even less is known of early Chinese +metallurgy than of the Egyptian. The remains of Mycenaean, Phoenician, +Babylonian, and Assyrian civilizations, stretching over the period from +1800 to 500 B.C., have yielded endless copper and bronze objects, the +former of considerable purity, and the latter a fairly constant +proportion of from 10% to 14% tin. The copper supply of the pre-Roman +world seems to have come largely, first from Sinai, and later from +Cyprus, and from the latter comes our word copper, by way of the Romans +shortening _aes cyprium_ (Cyprian copper) to _cuprum_. Research in this +island shows that it produced copper from 3000 B.C., and largely because +of its copper it passed successively under the domination of the +Egyptians, Assyrians, Phoenicians, Greeks, Persians, and Romans. The +bronze objects found in Cyprus show 2% to 10% of tin, although tin does +not, so far as modern research goes, occur on that island. There can be +no doubt that the Greeks obtained their metallurgy from the Egyptians, +either direct or second-hand--possibly through Mycenae or Phoenicia. +Their metallurgical gods and the tradition of Cadmus indicate this much. + +By way of literary evidences, the following lines from Homer (Iliad, +XVIII.) have interest as being the first preserved description in any +language of a metallurgical work. Hephaestus was much interrupted by +Thetis, who came to secure a shield for Achilles, and whose general +conversation we therefore largely omit. We adopt Pope's translation:-- + + There the lame architect the goddess found + Obscure in smoke, his forges flaming round, + While bathed in sweat from fire to fire he flew; + And puffing loud the roaring bellows blew. + * * * + In moulds prepared, the glowing ore (metal?) he pours. + * * * + "Vouchsafe, oh Thetis! at our board to share + The genial rites and hospitable fare; + While I the labours of the forge forego, + And bid the roaring bellows cease to blow." + Then from his anvil the lame artist rose; + Wide with distorted legs oblique he goes, + And stills the bellows, and (in order laid) + Locks in their chests his instruments of trade; + Then with a sponge, the sooty workman dress'd + His brawny arms embrown'd and hairy breast. + * * * + Thus having said, the father of the fires + To the black labours of his forge retires. + Soon as he bade them blow the bellows turn'd + Their iron mouths; and where the furnace burn'd + Resounding breathed: at once the blast expires, + And twenty forges catch at once the fires; + Just as the God directs, now loud, now low, + They raise a tempest, or they gently blow; + In hissing flames huge silver bars are roll'd, + And stubborn brass (copper?) and tin, and solid gold; + Before, deep fixed, the eternal anvils stand. + The ponderous hammer loads his better hand; + His left with tongs turns the vex'd metal round. + And thick, strong strokes, the doubling vaults rebound + Then first he formed the immense and solid shield; + +Even if we place the siege of Troy at any of the various dates from 1350 +to 1100 B.C., it does not follow that the epic received its final form +for many centuries later, probably 900-800 B.C.; and the experience of +the race in metallurgy at a much later period than Troy may have been +drawn upon to fill in details. It is possible to fill a volume with +indirect allusion to metallurgical facts and to the origins of the art, +from Greek mythology, from Greek poetry, from the works of the +grammarians, and from the Bible. But they are of no more technical value +than the metaphors from our own tongue. Greek literature in general is +singularly lacking in metallurgical description of technical value, and +it is not until Dioscorides (1st Century A.D.) that anything of much +importance can be adduced. Aristotle, however, does make an interesting +reference to what may be brass (see note on p. 410), and there can be no +doubt that if we had the lost work of Aristotle's successor, +Theophrastus (372-288 B.C.), on metals we should be in possession of the +first adequate work on metallurgy. As it is, we find the green and blue +copper minerals from Cyprus mentioned in his "Stones." And this is the +first mention of any particular copper ore. He also mentions (XIX.) +pyrites "which melt," but whether it was a copper variety cannot be +determined. Theophrastus further describes the making of verdigris (see +note 4, p. 440). From Dioscorides we get a good deal of light on copper +treatment, but as his objective was to describe medicinal preparations, +the information is very indirect. He states (V, 100) that "pyrites is a +stone from which copper is made." He mentions _chalcitis_ (copper +sulphide, see note on, p. 573); while his _misy_, _sory_, _melanteria_, +_caeruleum_, and _chrysocolla_ were all oxidation copper or iron +minerals. (See notes on p. 573.) In giving a method of securing +_pompholyx_ (zinc oxide), "the soot flies up when the copper refiners +sprinkle powdered _cadmia_ over the molten metal" (see note 26, p. 394); +he indirectly gives us the first definite indication of making brass, +and further gives some details as to the furnaces there employed, which +embraced bellows and dust chambers. In describing the making of flowers +of copper (see note 26, p. 538) he states that in refining copper, when +the "molten metal flows through its tube into a receptacle, the workmen +pour cold water on it, the copper spits and throws off the flowers." He +gives the first description of vitriol (see note 11, p. 572), and +describes the pieces as "shaped like dice which stick together in +bunches like grapes." Altogether, from Dioscorides we learn for the +first time of copper made from sulphide ores, and of the recovery of +zinc oxides from furnace fumes; and he gives us the first certain +description of making brass, and finally the first notice of blue +vitriol. + +The next author we have who gives any technical detail of copper work is +Pliny (23-79 A.D.), and while his statements carry us a little further +than Dioscorides, they are not as complete as the same number of words +could have afforded had he ever had practical contact with the subject, +and one is driven to the conclusion that he was not himself much of a +metallurgist. Pliny indicates that copper ores were obtained from veins +by underground mining. He gives the same minerals as Dioscorides, but is +a good deal confused over _chrysocolla_ and _chalcitis_. He gives no +description of the shapes of furnaces, but frequently mentions the +bellows, and speaks of the _cadmia_ and _pompholyx_ which adhered to the +walls and arches of the furnaces. He has nothing to say as to whether +fluxes are used or not. As to fuel, he says (XXXIII, 30) that "for +smelting copper and iron pine wood is the best." The following (XXXIV, +20) is of the greatest interest on the subject:--"Cyprian copper is +known as _coronarium_ and _regulare_; both are ductile.... In other +mines are made that known as _regulare_ and _caldarium_. These differ, +because the _caldarium_ is only melted, and is brittle to the hammer; +whereas the _regulare_ is malleable or ductile. All Cyprian copper is +this latter kind. But in other mines with care the difference can be +eliminated from _caldarium_, the impurities being carefully purged away +by smelting with fire, it is made into _regulare_. Among the remaining +kinds of copper the best is that of Campania, which is most esteemed for +vessels and utensils. This kind is made in several ways. At Capua it is +melted with wood, not with charcoal, after which it is sprinkled with +water and washed through an oak sieve. After it is melted a number of +times Spanish _plumbum argentum_ (probably pewter) is added to it in +proportion of ten pounds of the lead to one hundred pounds of copper, +and thereby it is made pliable and assumes that pleasing colour which in +other kinds of copper is effected by oil and the sun. In many parts of +the Italian provinces they make a similar kind of metal; but there they +add eight pounds of lead, and it is re-melted over charcoal because of +the scarcity of wood. Very different is the method carried on in Gaul, +particularly where the ore is smelted between red hot stones, for this +burns the metal and renders it black and brittle. Moreover, it is +re-melted only a single time, whereas the oftener this operation is +repeated the better the quality becomes. It is well to remark that all +copper fuses best when the weather is intensely cold." The red hot +stones in Gaul were probably as much figments of imagination as was the +assumption of one commentator that they were a reverberatory furnace. +Apart from the above, Pliny says nothing very direct on refining copper. +It is obvious that more than one melting was practised, but that +anything was known of the nature of oxidation by a blast and reduction +by poling is uncertain. We produce the three following statements in +connection with some bye-products used for medicinal purposes, which at +least indicate operations subsequent to the original melting. As to +whether they represent this species of refining or not, we leave it to +the metallurgical profession (XXXIV, 24):--"The flowers of copper are +used in medicine; they are made by fusing copper and moving it to +another furnace, where the rapid blast separates it into a thousand +particles, which are called flowers. These scales are also made when the +copper cakes are cooled in water (XXXIV, 35). _Smega_ is prepared in the +copper works; when the metal is melted and thoroughly smelted charcoal +is added to it and gradually kindled; after this, being blown upon by a +powerful bellows, it spits out, as it were, copper chaff (XXXIV, 37). +There is another product of these works easily distinguished from +_smega_, which the Greeks call _diphrygum_. This substance has three +different origins.... A third way of making it is from the residues +which fall to the bottom in copper furnaces. The difference between the +different substances (in the furnace) is that the copper itself flows +into a receiver; the slag makes its escape from the furnace; the flowers +float on the top (of the copper?), and the _diphrygum_ remains behind. +Some say that in the furnace there are certain masses of stone which, +being smelted, become soldered together, and that the copper fuses +around it, the mass not becoming liquid unless it is transferred to +another furnace. It thus forms a sort of knot, as it were, in the +metal." + +Pliny is a good deal confused over the copper alloys, failing to +recognise _aurichalcum_ as the same product as that made by mixing +_cadmia_ and molten copper. Further, there is always the difficulty in +translation arising from the fact that the Latin _aes_ was +indiscriminately copper, brass, and bronze. He does not, except in one +instance (XXXIV., 2), directly describe the mixture of _cadmia_ and +copper. "Next to Livian (copper) this kind (_corduban_, from Spain) most +readily absorbs _cadmia_, and becomes almost as excellent as +_aurichalcum_ for making _sesterces_." As to bronze, there is no very +definite statement; but the _argentatium_ given in the quotation above +from XXXIV, 20, is stated in XXXIV, 48, to be a mixture of tin and lead. +The Romans carried on most extensive copper mining in various parts of +their empire; these activities extended from Egypt through Cyprus, +Central Europe, the Spanish Peninsula, and Britain. The activity of such +works is abundantly evidenced in the mines, but very little remains upon +the surface to indicate the equipment; thus, while mining methods are +clear enough, the metallurgy receives little help from these sources. At +Rio Tinto there still remain enormous slag heaps from the Romans, and +the Phoenician miners before them. Professor W. A. Carlyle informs us +that the ore worked must have been almost exclusively sulphides, as only +negligible quantities of carbonates exist in the deposits; they probably +mixed basic and siliceous ores. There is some evidence of roasting, and +the slags run from .2 to .6%. They must have run down mattes, but as to +how they ultimately arrived at metallic copper there is no evidence to +show. + +The special processes for separating other metals from copper by +liquation and matting, or of refining by poling, etc., are none of them +clearly indicated in records or remains until we reach the 12th century. +Here we find very adequate descriptions of copper smelting and refining +by the Monk Theophilus (see Appendix B). We reproduce two paragraphs of +interest from Hendrie's excellent translation (p. 305 and 313): "Copper +is engendered in the earth. When a vein of which is found, it is +acquired with the greatest labour by digging and breaking. It is a stone +of a green colour and most hard, and naturally mixed with lead. This +stone, dug up in abundance, is placed upon a pile and burned after the +manner of chalk, nor does it change colour, but yet loses its hardness, +so that it can be broken up. Then, being bruised small, it is placed in +the furnace; coals and the bellows being applied, it is incessantly +forged by day and night. This should be done carefully and with caution; +that is, at first coals are placed in, then small pieces of stone are +distributed over them, and again coals, and then stone anew, and it is +thus arranged until it is sufficient for the size of the furnace. And +when the stone has commenced to liquefy, the lead flows out through some +small cavities, and the copper remains within. (313) Of the purification +of copper. Take an iron dish of the size you wish, and line it inside +and out with clay strongly beaten and mixed, and it is carefully dried. +Then place it before a forge upon the coals, so that when the bellows +act upon it the wind may issue partly within and partly above it, and +not below it. And very small coals being placed round it, place copper +in it equally, and add over it a heap of coals. When, by blowing a long +time, this has become melted, uncover it and cast immediately fine ashes +of coals over it, and stir it with a thin and dry piece of wood as if +mixing it, and you will directly see the burnt lead adhere to these +ashes like a glue. Which being cast out again superpose coals, and +blowing for a long time, as at first, again uncover it, and then do as +you did before. You do this until at length, by cooking it, you can +withdraw the lead entirely. Then pour it over the mould which you have +prepared for this, and you will thus prove if it be pure. Hold it with +pincers, glowing as it is, before it has become cold, and strike it with +a large hammer strongly over the anvil, and if it be broken or split you +must liquefy it anew as before." + +The next writer of importance was Biringuccio, who was contemporaneous +with Agricola, but whose book precedes _De Re Metallica_ by 15 years. +That author (III, 2) is the first to describe particularly the furnace +used in Saxony and the roasting prior to smelting, and the first to +mention fluxes in detail. He, however, describes nothing of matte +smelting; in copper refining he gives the whole process of poling, but +omits the pole. It is not until we reach _De Re Metallica_ that we find +adequate descriptions of the copper minerals, roasting, matte smelting, +liquation, and refining, with a wealth of detail which eliminates the +necessity for a large amount of conjecture regarding technical methods +of the time. + +[43] _Cadmia metallica fossilis_ (see note on p. 112). This was +undoubtedly the complex cobalt-arsenic-zinc minerals found in Saxony. In +the German translation, however, this is given as _Kalmey_, calamine, +which is unlikely from the association with pyrites. + +[44] The Roman _modius_ (_modulus_?) held about 550 cubic inches, the +English peck holding 535 cubic inches. Then, perhaps, his seven _moduli_ +would be roughly, 1 bushel 3 pecks, and 18 vessels full would be about +31 bushels--say, roughly, 5,400 lbs. of ore. + +[45] Exhausted liquation cakes (_panes aerei fathiscentes_). This is the +copper sponge resulting from the first liquation of lead, and still +contains a considerable amount of lead. The liquation process is +discussed in great detail in Book XI. + +[46] The method of this paragraph involves two main objectives--first, +the gradual enrichment of matte to blister copper; and, second, the +creation of large cakes of copper-lead-silver alloy of suitable size and +ratio of metals for liquation. This latter process is described in +detail in Book XI. The following groupings show the circuit of the +various products, the "lbs." being Roman _librae_:-- + + CHARGE. PRODUCTS. + + { Crude ore 5,400 lbs. } Primary matte (1) 600 lbs. + { Lead slags 3 cartloads } + 1st { Schist 1 cartload } Silver-copper alloy (A) 50 " + { Flux 20 lbs. } + { Concentrates from } Slags (B) + { slags & accretions Small quantity } + + { Primary matte (1) 1,800 lbs. } Secondary matte (2) 1,800 lbs. + { Hearth-lead & litharge 1,200 " } + { Lead ore 300 " } Silver-copper-lead + 2nd { Rich hard cakes (A_{4}) 500 " } alloy (liquation + { Liquated cakes 200 " } cakes) (A_{2}) 1,200 " + { Slags (B) } + { Concentrates from } Slags (B_{2}) + { accretions } + + { Secondary matte (2) 1,800 lbs. } Tertiary matte (3) 1,300 lbs. + { Hearth-lead & litharge 1,200 " } Silver-copper-lead + { Lead ore 300 " } alloy (liquation + 3rd { Rich hard cakes (A_{4}) 500 " } cakes) (A_{3}) 1,100 " + { Slags (B_{2}) } Slags (B_{3}) + { Concentrates from } + { accretions } + + { Tertiary matte (3) 11 cartloads } Quaternary hard cakes + { Poor hard cakes (A_{5}) 3 " } matte (4) 2,000 lbs. + 4th { Slags (B_{3}) } Rich hard cakes of + { Concentrates from } matte (A_{4}) 1,500 " + { accretions } + + { Roasted quartz } Poor hard cakes of + 5th { Matte (4) (three } matte (A_{5}) 1,500 lbs. + { times roasted) 11 cartloads } Final cakes of matte (5) + +6th Final matte three times roasted is smelted to blister copper. + +The following would be a rough approximation of the value of the various +products:-- + + (1.) Primary matte = 158 ounces troy per short ton. + (2.) Secondary matte = 85 " " " + (3.) Tertiary matte = 60 " " " + (4.) Quaternary matte = Indeterminate. + A. Copper-silver alloy = 388 ounces Troy per short ton. + A_{2} Copper-silver-lead alloy = 145 " " " + A_{3} " " " = 109 " " " + A_{4} Rich hard cakes = 97 " " " + A_{5} Poor hard cakes = Indeterminate. + Final blister copper = 12 ozs. Troy per short ton. + +[47] This expression is usually used for hearth-lead, but in this case +the author is apparently confining himself to lead ore, and apparently +refers to lead carbonates. The German Translation gives _pleyschweiss_. +The pyrites mentioned in this paragraph may mean galena, as pyrites was +to Agricola a sort of genera. + +[48] (_Excoquitur_) ... "_si verò pyrites, primò è fornace, ut +Goselariae videre licet, in catinum defluit liquor quidam candidus, +argento inimicus et nocivus; id enim comburit: quo circa recrementis, +quae supernatant, detractis effunditur: vel induratus conto uncinato +extrahitur: eundem liquorem parietes fornacis exudant._" In the Glossary +the following statement appears: "_Liquor candidus primo è fornace +defluens cum Goselariae excoquitur pyrites,--kobelt; quem parietes +fornacis exudant,--conterfei._" In this latter statement Agricola +apparently recognised that there were two different substances, _i.e._, +that the substance found in the furnace walls--_conterfei_--was not the +same substance as that which first flowed from the furnace--_kobelt_. We +are at no difficulty in recognizing _conterfei_ as metallic zinc; it was +long known by that term, and this accidental occurrence is repeatedly +mentioned by other authors after Agricola. The substance which first +flowed into the forehearth presents greater difficulties; it certainly +was not zinc. In _De Natura Fossilium_ (p. 347), Agricola says that at +Goslar the lead has a certain white slag floating upon it, the "colour +derived from the pyrites (_pyriten argenteum_) from which it was +produced." _Pyriten argenteum_ was either marcasite or mispickel, +neither of which offers much suggestion; nor are we able to hazard an +explanation of value. + +HISTORICAL NOTE ON ZINC. The history of zinc metallurgy falls into two +distinct lines--first, that of the metal, and second, that of zinc ore, +for the latter was known and used to make brass by cementation with +copper and to yield oxides by sublimation for medicinal purposes, nearly +2,000 years before the metal became generally known and used in Europe. + +There is some reason to believe that metallic zinc was known to the +Ancients, for bracelets made of it, found in the ruins of Cameros (prior +to 500 B.C.), may have been of that age (Raoul Jagnaux, _Traité de +Chimie Générale_, 1887, II, 385); and further, a passage in Strabo (63 +B.C.-24 A.D.) is of much interest. He states: (XIII, 1, 56) "There is +found at Andeira a stone which when burnt becomes iron. It is then put +into a furnace, together with some kind of earth, when it distils a mock +silver (_pseudargyrum_), or with the addition of copper it becomes the +compound called _orichalcum_. There is found a mock silver near Tismolu +also." (Hamilton's Trans., II, p. 381). About the Christian era the +terms _orichalcum_ or _aurichalcum_ undoubtedly refer to brass, but +whether these terms as used by earlier Greek writers do not refer to +bronze only, is a matter of considerable doubt. Beyond these slight +references we are without information until the 16th Century. If the +metal was known to the Ancients it must have been locally, for by its +greater adaptability to brass-making it would probably have supplanted +the crude melting of copper with zinc minerals. + +It appears that the metal may have been known in the Far East prior to +such knowledge in Europe; metallic zinc was imported in considerable +quantities from the East as early as the 16th and 17th centuries under +such terms as _tuteneque_, _tuttanego_, _calaëm_, and _spiauter_--the +latter, of course, being the progenitor of our term spelter. The +localities of Eastern production have never been adequately +investigated. W. Hommel (Engineering and Mining Journal, June 15, 1912) +gives a very satisfactory review of the Eastern literature upon the +subject, and considers that the origin of manufacture was in India, +although the most of the 16th and 17th Century product came from China. +The earliest certain description seems to be some recipes for +manufacture quoted by Praphulla Chandra Ray (A History of Hindu +Chemistry, London, 1902, p. 39) dating from the 11th to the 14th +Centuries. There does not appear to be any satisfactory description of +the Chinese method until that of Sir George Staunton (Journal Asiatique +Paris, 1835, p. 141.) We may add that spelter was produced in India by +crude distillation of calamine in clay pots in the early part of the +19th Century (Brooke, Jour. Asiatic Soc. of Bengal, vol. XIX, 1850, p. +212), and the remains of such smelting in Rajputana are supposed to be +very ancient. + +The discovery of zinc in Europe seems to have been quite independent of +the East, but precisely where and when is clouded with much uncertainty. +The _marchasita aurea_ of Albertus Magnus has been called upon to serve +as metallic zinc, but such belief requires a hypothesis based upon a +great deal of assumption. Further, the statement is frequently made that +zinc is mentioned in Basil Valentine's Triumphant Chariot of Antimony +(the only one of the works attributed to this author which may date +prior to the 17th Century), but we have been unable to find any such +reference. The first certain mention of metallic zinc is generally +accredited to Paracelsus (1493-1541), who states (_Liber Mineralium_ +II.): "Moreover there is another metal generally unknown called +_zinken_. It is of peculiar nature and origin; many other metals +adulterate it. It can be melted, for it is generated from three fluid +principles; it is not malleable. Its colour is different from other +metals and does not resemble others in its growth. Its ultimate matter +(_ultima materia_) is not to me yet fully known. It admits of no mixture +and does not permit of the _fabricationes_ of other metals. It stands +alone entirely to itself." We do not believe that this book was +published until after Agricola's works. Agricola introduced the +following statements into his revised edition of _Bermannus_ (p. 431), +published in 1558: "It (a variety of pyrites) is almost the colour of +galena, but of entirely different components. From it there is made gold +and silver, and a great quantity is dug in Reichenstein, which is in +Silesia, as was recently reported to me. Much more is found at Raurici, +which they call _zincum_, which species differs from pyrites, for the +latter contains more silver than gold, the former only gold or hardly +any silver." In _De Natura Fossilium_ (p. 368): "For this _cadmia_ is +put, in the same way as quicksilver, in a suitable vessel so that the +heat of the fire will cause it to sublime, and from it is made a black +or brown or grey body which the Alchemists call _cadmia sublimata_. This +possesses corrosive properties to the highest degree. Cognate with this +_cadmia_ and pyrites is a compound which the Noricans and Rhetians call +_zincum_." We leave it to readers to decide how near this comes to +metallic zinc; in any event, he apparently did not recognise his +_conterfei_ from the furnaces as the same substance as the _zincum_ from +Silesia. The first correlation of these substances was apparently by +Lohneys, in 1617, who says (_Vom Bergwerk_, p. 83-4): "When the people +in the smelting works are smelting, there is made under the furnace and +in the cracks in the walls among the badly plastered stones, a metal +which is called _zinc_ or _counterfeht_, and when the wall is scraped it +falls into a vessel placed to receive it. This metal greatly resembles +tin, but it is harder and less malleable.... The Alchemists have a great +desire for this _zinc_ or bismuth." That this metal originated from +blende or calamine was not recognised until long after, and Libavis +(_Alchymia_, Frankfort, 1606), in describing specimens which came from +the East, did not so identify it, this office being performed by +Glauber, who says (_De Prosperitate Germanias_, Amsterdam, 1656): "Zink +is a volatile mineral or half-ripe metal when it is extracted from its +ore. It is more brilliant than tin and not so fusible or malleable ... +it turns (copper) into brass, as does _lapis calaminaris_, for indeed +this stone is nothing but infusible zinc, and this zinc might be called +a fusible _lapis calaminaris_, inasmuch as both of them partake of the +same nature.... It sublimates itself up into the cracks of the furnace, +whereupon the smelters frequently break it out." The systematic +distillation of zinc from calamine was not discovered in Europe until +the 18th Century. Henkel is generally accredited with the first +statement to that effect. In a contribution published as an Appendix to +his other works, of which we have had access only to a French +translation (_Pyritologie_, Paris, 1760, p. 494), he concludes that zinc +is a half-metal of which the best ore is calamine, but believes it is +always associated with lead, and mentions that an Englishman lately +arrived from Bristol had seen it being obtained from calamine in his own +country. He further mentions that it can be obtained by heating calamine +and lead ore mixed with coal in a thick earthen vessel. The Bristol +works were apparently those of John Champion, established about 1740. +The art of distillation was probably learned in the East. + +Definite information as to the zinc minerals goes back to but a little +before the Christian Era, unless we accept nebular references to +_aurichalcum_ by the poets, or what is possibly zinc ore in the "earth" +mentioned by Aristotle (_De Mirabilibus_, 62): "Men say that the copper +of the Mossynoeci is very brilliant and white, no tin being mixed with +it; but there is a kind of earth there which is melted with it." This +might quite well be an arsenical mineral. But whether we can accept the +poets or Aristotle or the remark of Strabo given above, as sufficient +evidence or not, there is no difficulty with the description of _cadmia_ +and _pompholyx_ and _spodos_ of Dioscorides (1st Century), parts of +which we reproduce in note 26, p. 394. His _cadmia_ is described as +rising from the copper furnaces and clinging to the iron bars, but he +continues: "_Cadmia_ is also prepared by burning the stone called +pyrites, which is found near Mt. Soloi in Cyprus.... Some say that +_cadmia_ may also be found in stone quarries, but they are deceived by +stones having a resemblance to _cadmia_." _Pompholyx_ and _spodos_ are +evidently furnace calamine. From reading the quotation given on p. 394, +there can be no doubt that these materials, natural or artificial, were +used to make brass, for he states (V, 46): "White _pompholyx_ is made +every time that the artificer in the working and perfecting of the +copper sprinkles powdered _cadmia_ upon it to make it more perfect, the +soot arising from this ... is _pompholyx_." Pliny is confused between +the mineral _cadmia_ and furnace _calamine_, and none of his statements +are very direct on the subject of brass making. His most pointed +statement is (XXXIV, 2): "... Next to Livian (copper) this kind best +absorbs _cadmia_, and is almost as good as _aurichalcum_ for making +sesterces and double asses." As stated above, there can be little doubt +that the _aurichalcum_ of the Christian Era was brass, and further, we +do know of brass sesterces of this period. Other Roman writers of this +and later periods refer to earth used with copper for making brass. +Apart from these evidences, however, there is the evidence of analyses +of coins and objects, the earliest of which appears to be a large brass +of the Cassia family of 20 B.C., analyzed by Phillips, who found 17.3% +zinc (Records of Mining and Metallurgy, London, 1857, p. 13). Numerous +analyses of coins and other objects dating during the following century +corroborate the general use of brass. Professor Gowland (Presidential +Address, Inst. of Metals, 1912) rightly considers the Romans were the +first to make brass, and at about the above period, for there appears to +be no certainty of any earlier production. The first adequate technical +description of brass making is in about 1200 A.D. being that of +Theophilus, who describes (Hendrie's Trans., p. 307) calcining +_calamina_ and mixing it with finely divided copper in glowing +crucibles. The process was repeated by adding more calamine and copper +until the pots were full of molten metal. This method is repeatedly +described with minor variations by Biringuccio, Agricola (_De Nat. +Fos._), and others, down to the 18th Century. For discussion of the zinc +minerals see note on p. 112. + +[49] "_... non raro, ut nonnulli pyritae sunt, candida...._" This is +apparently the unknown substance mentioned above. + +[50] One _drachma_ is about 3 ounces Troy per short ton. Three _unciae_ +are about 72 ounces 6 dwts. Troy per short ton. + +[51] In this section, which treats of the metallurgy of _plumbum +candidum_, "tin," the word _candidum_ is very often omitted in the +Latin, leaving only _plumbum_, which is confusing at times with lead. +The black tin-stone, _lapilli nigri_ has been treated in a similar +manner, _lapilli_ (small stones) constantly occurring alone in the +Latin. This has been rendered as "tin-stone" throughout, and the +material prior to extraction of the _lapilli nigri_ has been rendered +"tin-stuff," after the Cornish. + +[52] "_... ex saxis vilibus, quae natura de diversa materia composuit._" +The Glossary gives _grindstein_. Granite (?). + +[53] HISTORICAL NOTES ON TIN METALLURGY. The first appearance of tin +lies in the ancient bronzes. And while much is written upon the "Bronze +Age" by archæologists, we seriously doubt whether or not a large part of +so-called bronze is not copper. In any event, this period varied with +each race, and for instance, in Britain may have been much later than +Egyptian historic times. The bronze articles of the IV Dynasty (from +3800 to 4700 B.C. depending on the authority) place us on certain ground +of antiquity. Professor Gowland (Presidential Address, Inst. of Metals, +London, 1912) maintains that the early bronzes were the result of direct +smelting of stanniferous copper ores, and while this may be partially +true for Western Europe, the distribution and nature of the copper +deposits do not warrant this assumption for the earlier scenes of human +activity--Asia Minor, Egypt, and India. Further, the lumps of rough tin +and also of copper found by Borlase (Tin Mining in Spain, Past and +Present, London, 1897, p. 25) in Cornwall, mixed with bronze celts under +conditions certainly indicating the Bronze Age, is in itself of +considerable evidence of independent melting. To our mind the vast +majority of ancient bronzes must have been made from copper and tin +mined and smelted independently. As to the source of supply of ancient +tin, we are on clear ground only with the advent of the Phoenicians, +1500-1000 B.C., who, as is well known, distributed to the ancient world +a supply from Spain and Britain. What the source may have been prior to +this time has been subject to much discussion, and while some slender +threads indicate the East, we believe that a more local supply to Egypt, +etc., is not impossible. The discovery of large tin fields in Central +Africa and the native-made tin ornaments in circulation among the +negroes, made possible the entrance of the metal into Egypt along the +trade routes. Further, we see no reason why alluvial tin may not have +existed within easy reach and have become exhausted. How quickly such a +source of metal supply can be forgotten and no evidence remain, is +indicated by the seldom remembered alluvial gold supply from Ireland. +However, be these conjectures as they may, the East has long been the +scene of tin production and of transportation activity. Among the +slender evidences that point in this direction is that the Sanskrit term +for tin is _kastira_, a term also employed by the Chaldeans, and +represented in Arabic by _kasdir_, and it may have been the progenitor +of the Greek _cassiteros_. There can be no doubt that the Phoenicians +also traded with Malacca, etc., but beyond these threads there is little +to prove the pre-western source. The strained argument of Beckmann +(Hist. of Inventions, vol. II., p. 207) that the _cassiteros_ of Homer +and the _bedil_ of the Hebrews was possibly not tin, and that tin was +unknown at this time, falls to the ground in the face of the vast amount +of tin which must have been in circulation to account for the bronze +used over a period 2,000 years prior to those peoples. Tin is early +mentioned in the Scriptures (Numbers XXXI, 22), being enumerated among +the spoil of the Midianites (1200 B.C.?), also Ezekiel (600 B.C., XXVII, +12) speaks of tin from Tarshish (the Phoenician settlement on the +coast of Spain). According to Homer tin played considerable part in +Vulcan's metallurgical stores. Even approximately at what period the +Phoenicians began their distribution from Spain and Britain cannot be +determined. They apparently established their settlements at Gades +(Cadiz) in Tarshish, beyond Gibraltar, about 1100 B.C. The remains of +tin mining in the Spanish peninsula prior to the Christian Era indicate +most extensive production by the Phoenicians, but there is little +evidence as to either mining or smelting methods. Generally as to the +technical methods of mining and smelting tin, we are practically without +any satisfactory statement down to Agricola. However, such scraps of +information as are available are those in Homer (see note on p. 402), +Diodorus, and Pliny. + +Diodorus says (V, 2) regarding tin in Spain: "They dig it up, and melt +it down in the same way as they do gold and silver;" and again, speaking +of the tin in Britain, he says: "These people make tin, which they dig +up with a great deal of care and labour; being rocky, the metal is mixed +with earth, out of which they melt the metal, and then refine it." Pliny +(XXXIV, 47), in the well-known and much-disputed passage: "Next to be +considered are the characteristics of lead, which is of two kinds, black +and white. The most valuable is the white; the Greeks called it +_cassiteros_, and there is a fabulous story of its being searched for +and carried from the islands of Atlantis in barks covered with hides. +Certainly it is obtained in Lusitania and Gallaecia on the surface of +the earth from black-coloured sand. It is discovered by its great +weight, and it is mixed with small pebbles in the dried beds of +torrents. The miners wash these sands, and that which settles they heat +in the furnace. It is also found in gold mines, which are called +_alutiae_. A stream of water passing through detaches small black +pebbles variegated with white spots, the weight of which is the same as +gold. Hence it is that they remain in the baskets of the gold collectors +with the gold; afterward, they are separated in a _camillum_ and when +melted become white lead." + +There is practically no reference to the methods of Cornish tin-working +over the whole period of 2,000 years that mining operations were carried +on there prior to the Norman occupation. From then until Agricola's +time, a period of some four centuries, there are occasional references +in Stannary Court proceedings, Charters, and such-like official +documents which give little metallurgical insight. From a letter of +William de Wrotham, Lord Warden of the Stannaries, in 1198, setting out +the regulations for the impost on tin, it is evident that the black tin +was smelted once at the mines and that a second smelting or refining was +carried out in specified towns under the observation of the Crown +Officials. In many other official documents there are repeated +references to the right to dig turfs and cut wood for smelting the tin. +Under note 8, p. 282, we give some further information on tin +concentration, and the relation of Cornish and German tin miners. +Biringuccio (1540) gives very little information on tin metallurgy, and +we are brought to _De Re Metallica_ for the first clear exposition. + +As to the description on these pages it must be remembered that the +tin-stone has been already roasted, thus removing some volatile +impurities and oxidizing others, as described on page 348. The furnaces +and the methods of working the tin, here described, are almost identical +with those in use in Saxony to-day. In general, since Agricola's time +tin has not seen the mechanical and metallurgical development of the +other metals. The comparatively small quantities to be dealt with; the +necessity of maintaining a strong reducing atmosphere, and consequently +a mild cold blast; and the comparatively low temperature demanded, gave +little impetus to other than crude appliances until very modern times. + +[54] _Aureo nummo_. German Translation gives _reinschen gülden_, which +was the equivalent of about $1.66, or 6.9 shillings. The purchasing +power of money was, however, several times as great as at present. + +[55] In the following descriptions of iron-smelting, we have three +processes described; the first being the direct reduction of malleable +iron from ore, the second the transition stage then in progress from the +direct to indirect method by way of cast-iron; and the third a method of +making steel by cementation. The first method is that of primitive +iron-workers of all times and all races, and requires little comment. A +pasty mass was produced, which was subsequently hammered to make it +exude the slag, the hammered mass being the ancient "bloom." The second +process is of considerable interest, for it marks one of the earliest +descriptions of working iron in "a furnace similar to a blast furnace, +but much wider and higher." This original German _Stückofen_ or high +bloomery furnace was used for making "masses" of wrought-iron under +essentially the same conditions as its progenitor the forge--only upon a +larger scale. With high temperatures, however, such a furnace would, if +desired, yield molten metal, and thus the step to cast-iron as a +preliminary to wrought-iron became very easy and natural, in fact +Agricola mentions above that if the iron is left to settle in the +furnace it becomes hard. The making of malleable iron by subsequent +treatment of the cast-iron--the indirect method--originated in about +Agricola's time, and marks the beginning of one of those subtle economic +currents destined to have the widest bearing upon civilization. It is to +us uncertain whether he really understood the double treatment or not. +In the above paragraph he says from ore "once or twice smelted they make +iron," etc., and in _De Natura Fossilium_ (p. 339) some reference is +made to pouring melted iron, all of which would appear to be cast-iron. +He does not, however, describe the 16th Century method of converting +cast into wrought iron by way of in effect roasting the pig iron to +eliminate carbon by oxidation, with subsequent melting into a "ball" or +"mass." It must be borne in mind that puddling for this purpose did not +come into use until the end of the 18th Century. A great deal of +discussion has arisen as to where and at what time cast-iron was made +systematically, but without satisfactory answer; in any event, it seems +to have been in about the end of the 14th Century, as cast cannon began +to appear about that time. It is our impression that the whole of this +discussion on iron in _De Re Metallica_ is an abstract from Biringuccio, +who wrote 15 years earlier, as it is in so nearly identical terms. Those +interested will find a translation of Biringuccio's statement with +regard to steel in Percy's Metallurgy of Iron and Steel, London, 1864, +p. 807. + +HISTORICAL NOTE ON IRON SMELTING. The archæologists' division of the +history of racial development into the Stone, Bronze, and Iron Ages, +based upon objects found in tumuli, burial places, etc., would on the +face of it indicate the prior discovery of copper metallurgy over iron, +and it is generally so maintained by those scientists. The metallurgists +have not hesitated to protest that while this distinction of "Ages" may +serve the archæologists, and no doubt represents the sequence in which +the metal objects are found, yet it by no means follows that this was +the order of their discovery or use, but that iron by its rapidity of +oxidation has simply not been preserved. The arguments which may be +advanced from our side are in the main these. Iron ore is of more +frequent occurrence than copper ores, and the necessary reduction of +copper oxides (as most surface ores must have been) to fluid metal +requires a temperature very much higher than does the reduction of iron +oxides to wrought-iron blooms, which do not necessitate fusion. The +comparatively greater simplicity of iron metallurgy under primitive +conditions is well exemplified by the hill tribes of Northern Nigeria, +where in village forges the negroes reduce iron sufficient for their +needs, from hematite. Copper alone would not be a very serviceable metal +to primitive man, and he early made the advance to bronze; this latter +metal requires three metallurgical operations, and presents immeasurably +greater difficulties than iron. It is, as Professor Gowland has +demonstrated (Presidential Address, Inst. of Metals, London, 1912) quite +possible to make bronze from melting stanniferous copper ores, yet such +combined occurrence at the surface is rare, and, so far as known, the +copper sources from which Asia Minor and Egypt obtained their supply do +not contain tin. It seems to us, therefore, that in most cases the +separate fusions of different ores and their subsequent re-melting were +required to make bronze. The arguments advanced by the archæologists +bear mostly upon the fact that, had iron been known, its superiority +would have caused the primitive races to adopt it, and we should not +find such an abundance of bronze tools. As to this, it may be said that +bronze weapons and tools are plentiful enough in Egyptian, Mycenæan, and +early Greek remains, long after iron was demonstrably well known. There +has been a good deal pronounced by etymologists on the history of iron +and copper, for instance, by Max Müller, (Lectures on the Science of +Language, Vol. II, p. 255, London, 1864), and many others, but the +amazing lack of metallurgical knowledge nullifies practically all their +conclusions. The oldest Egyptian texts extant, dating 3500 B.C., refer +to iron, and there is in the British Museum a piece of iron found in the +Pyramid of Kephron (3700 B.C.) under conditions indicating its +co-incident origin. There is exhibited also a fragment of oxidized iron +lately found by Professor Petrie and placed as of the VI Dynasty (B.C. +3200). Despite this evidence of an early knowledge of iron, there is +almost a total absence of Egyptian iron objects for a long period +subsequent to that time, which in a measure confirms the view of its +disappearance rather than that of ignorance of it. Many writers have +assumed that the Ancients must have had some superior art of hardening +copper or bronze, because the cutting of the gigantic stonework of the +time could not have been done with that alloy as we know it; no such +hardening appears among the bronze tools found, and it seems to us that +the argument is stronger that the oldest Egyptian stoneworkers employed +mostly iron tools, and that these have oxidized out of existence. The +reasons for preferring copper alloys to iron for decorative objects were +equally strong in ancient times as in the present day, and accounts +sufficiently for these articles, and, therefore, iron would be devoted +to more humble objects less likely to be preserved. Further, the +Egyptians at a later date had some prejudices against iron for sacred +purposes, and the media of preservation of most metal objects were not +open to iron. We know practically nothing of very early Egyptian +metallurgy, but in the time of Thotmes III. (1500 B.C.) bellows were +used upon the forge. + +Of literary evidences the earliest is in the Shoo King among the Tribute +of Yü (2500 B.C.?). Iron is frequently mentioned in the Bible, but it is +doubtful if any of the early references apply to steel. There is +scarcely a Greek or Latin author who does not mention iron in some +connection, and of the earliest, none are so suggestive from a +metallurgical point of view as Homer, by whom "laboured" mass +(wrought-iron?) is often referred to. As, for instance, in the Odyssey +(I., 234) Pallas in the guise of Mentes, says according to Pope: + + "Freighted with iron from my native land + I steer my voyage to the Brutian strand, + To gain by commerce for the laboured mass + A just proportion of refulgent brass." + +(Brass is modern poetic licence for copper or bronze). Also, in the +Odyssey (IX, 465) when Homer describes how Ulysses plunged the stake +into Cyclop's eye, we have the first positive evidence of steel, +although hard iron mentioned in the Tribute of Yü, above referred to, is +sometimes given as steel: + + "And as when armourers temper in the ford + The keen-edg'd pole-axe, or the shining sword, + The red-hot metal hisses in the lake." + +No doubt early wrought-iron was made in the same manner as Agricola +describes. We are, however, not so clear as to the methods of making +steel. Under primitive methods of making wrought-iron it is quite +possible to carburize the iron sufficiently to make steel direct from +ore. The primitive method of India and Japan was to enclose lumps of +wrought-iron in sealed crucibles with charcoal and sawdust, and heat +them over a long period. Neither Pliny nor any of the other authors of +the period previous to the Christian Era give us much help on steel +metallurgy, although certain obscure expressions of Aristotle have been +called upon (for instance, St. John V. Day, Prehistoric Use of Iron and +Steel, London, 1877, p. 134) to prove its manufacture by immersing +wrought-iron in molten cast-iron. + +[56] _Quae vel aerosa est, vel cocta_. It is by no means certain that +_cocta_, "cooked" is rightly translated, for the author has not hitherto +used this expression for heated. This may be residues from roasting and +leaching pyrites for vitriol, etc. + +[57] Agricola draws no sharp line of distinction between antimony the +metal, and its sulphide. He uses the Roman term _stibi_ or _stibium_ +(_Interpretatio_,--_Spiesglas_) throughout this book, and evidently in +most cases means the sulphide, but in others, particularly in parting +gold and silver, metallic antimony would be reduced out. We have been in +much doubt as to the term to introduce into the text, as the English +"stibnite" carries too much precision of meaning. Originally the +"antimony" of trade was the sulphide. Later, with the application of +that term to the metal, the sulphide was termed "grey antimony," and we +have either used _stibium_ for lack of better alternative, or adopted +"grey antimony." The method described by Agricola for treating antimony +sulphide is still used in the Harz, in Bohemia, and elsewhere. The +stibnite is liquated out at a low heat and drips from the upper to the +lower pot. The resulting purified antimony sulphide is the modern +commercial "crude antimony" or "grey antimony." + +HISTORICAL NOTE ON THE METALLURGY OF ANTIMONY. The Egyptologists have +adopted the term "antimony" for certain cosmetics found in Egyptian +tombs from a very early period. We have, however, failed to find any +reliable analyses which warrant this assumption, and we believe that it +is based on the knowledge that antimony was used as a base for eye +ointments in Greek and Roman times, and not upon proper chemical +investigation. It may be that the ideograph which is interpreted as +antimony may really mean that substance, but we only protest that the +chemist should have been called in long since. In St. Jerome's +translation of the Bible, the cosmetic used by Jezebel (II. Kings IX, +30) and by the lady mentioned by Ezekiel (XXIII, 40), "who didst wash +thyself and paintedst thine eyes" is specifically given as _stibio_. Our +modern translation carries no hint of the composition of the cosmetic, +and whether some of the Greek or Hebrew MSS. do furnish a basis for such +translation we cannot say. The Hebrew term for this mineral was _kohl_, +which subsequently passed into "alcool" and "alkohol" in other +languages, and appears in the Spanish Bible in the above passage in +Ezekiel as _alcoholaste_. The term _antimonium_ seems to have been first +used in Latin editions of Geber published in the latter part of the 15th +Century. In any event, the metal is clearly mentioned by Dioscorides +(1st Century), who calls it _stimmi_, and Pliny, who termed it +_stibium_, and they leave no doubt that it was used as a cosmetic for +painting the eyebrows and dilating the eyes. Dioscorides (V, 59) says: +"The best _stimmi_ is very brilliant and radiant. When broken it divides +into layers with no part earthy or dirty; it is brittle. Some call it +_stimmi_, others _platyophthalmon_ (wide eyed); others _larbason_, +others _gynaekeion_ (feminine).... It is roasted in a ball of dough with +charcoal until it becomes a cinder.... It is also roasted by putting it +on live charcoal and blowing it. If it is roasted too much it becomes +lead." Pliny states (XXXIII, 33 and 34): "In the same mines in which +silver is found, properly speaking there is a stone froth. It is white +and shining, not transparent; is called _stimmi_, or _stibi_, or +_alabastrum_, and _larbasis_. There are two kinds of it, the male and +the female. The most approved is the female, the male being more uneven, +rougher, less heavy, not so radiant, and more gritty. The female kind is +bright and friable, laminar and not globular. It is astringent and +refrigerative, and its principal use is for the eyes.... It is burned in +manure in a furnace, is quenched with milk, ground with rain water in a +mortar, and while thus turbid it is poured into a copper vessel and +purified with nitrum ... above all in roasting it care should be taken +that it does not turn to lead." There can be little doubt from +Dioscorides' statement of its turning to lead that he had seen the metal +antimony, although he thought it a species of lead. Of further interest +in connection with the ancient knowledge of the metal is the Chaldean +vase made of antimony described by Berthelot (_Comptes Rendus_, 1887, +CIV, 265). It is possible that Agricola knew the metal, although he +gives no details as to de-sulphurizing it or for recovering the metal +itself. In _De Natura Fossilium_ (p. 181) he makes a statement which +would indicate the metal, "_Stibium_ when melted in the crucible and +refined has as much right to be regarded as a metal as is accorded to +lead by most writers. If when smelted a certain portion be added to tin, +a printer's alloy is made from which type is cast that is used by those +who print books." Basil Valentine, in his "Triumphal Chariot of +Antimony," gives a great deal that is new with regard to this metal, +even if we can accredit the work with no earlier origin than its +publication--about 1600; it seems possible however, that it was written +late in the 15th Century (see Appendix B). He describes the preparation +of the metal from the crude ore, both by roasting and reduction from the +oxide with argol and saltpetre, and also by fusing with metallic iron. +While the first description of these methods is usually attributed to +Valentine, it may be pointed out that in the _Probierbüchlein_ (1500) as +well as in Agricola the separation of silver from iron by antimony +sulphide implies the same reaction, and the separation of silver and +gold with antimony sulphide, often attributed to Valentine, is +repeatedly set out in the _Probierbüchlein_ and in _De Re Metallica_. +Biringuccio (1540) has nothing of importance to say as to the treatment +of antimonial ores, but mentions it as an alloy for bell-metal, which +would imply the metal. + +[58] HISTORICAL NOTE ON THE METALLURGY OF QUICKSILVER. The earliest +mention of quicksilver appears to have been by Aristotle +(_Meteorologica_ IV, 8, 11), who speaks of it as fluid silver (_argyros +chytos_). Theophrastus (105) states: "Such is the production of +quicksilver, which has its uses. This is obtained from cinnabar rubbed +with vinegar in a brass mortar with a brass pestle." (Hill's Trans., p. +139). Theophrastus also (103) mentions cinnabar from Spain and +elsewhere. Dioscorides (V, 70) appears to be the first to describe the +recovery of quicksilver by distillation: "Quicksilver (_hydrargyros_, +_i.e._, liquid silver) is made from _ammion_, which is called +_cinnabari_. An iron bowl containing _cinnabari_ is put into an earthen +vessel and covered over with a cup-shaped lid smeared with clay. Then it +is set on a fire of coals and the soot which sticks to the cover when +wiped off and cooled is quicksilver. Quicksilver is also found in drops +falling from the walls of the silver mines. Some say there are +quicksilver mines. It can be kept only in vessels of glass, lead, tin +(?), or silver, for if put in vessels of any other substances it +consumes them and flows through." Pliny (XXXIII, 41): "There has been +discovered a way of extracting _hydrargyros_ from the inferior _minium_ +as a substitute for quicksilver, as mentioned. There are two methods: +either by pounding _minium_ and vinegar in a brass mortar with a brass +pestle, or else by putting _minium_ into a flat earthen dish covered +with a lid, well luted with potter's clay. This is set in an iron pan +and a fire is then lighted under the pan, and continually blown by a +bellows. The perspiration collects on the lid and is wiped off and is +like silver in colour and as liquid as water." Pliny is somewhat +confused over the _minium_--or the text is corrupt, for this should be +the genuine _minium_ of Roman times. The methods of condensation on the +leaves of branches placed in a chamber, of condensing in ashes placed +over the mouth of the lower pot, and of distilling in a retort, are +referred to by Biringuccio (A.D. 1540), but with no detail. + +[59] Most of these methods depend upon simple liquation of native +bismuth. The sulphides, oxides, etc., could not be obtained without +fusing in a furnace with appropriate de-sulphurizing or reducing agents, +to which Agricola dimly refers. In _Bermannus_ (p. 439), he says: +"_Bermannus_.--I will show you another kind of mineral which is numbered +amongst metals, but appears to me to have been unknown to the Ancients; +we call it _bisemutum_. _Naevius_.--Then in your opinion there are more +kinds of metals than the seven commonly believed? _Bermannus_.--More, I +consider; for this which just now I said we called _bisemutum_, cannot +correctly be called _plumbum candidum_ (tin) nor _nigrum_ (lead), but is +different from both, and is a third one. _Plumbum candidum_ is whiter +and _plumbum nigrum_ is darker, as you see. _Naevius_.--We see that this +is of the colour of _galena_. _Ancon_.--How then can _bisemutum_, as you +call it, be distinguished from _galena_? _Bermannus_.--Easily; when you +take it in your hands it stains them with black unless it is quite hard. +The hard kind is not friable like _galena_, but can be cut. It is +blacker than the kind of crude silver which we say is almost the colour +of lead, and thus is different from both. Indeed, it not rarely contains +some silver. It generally shows that there is silver beneath the place +where it is found, and because of this our miners are accustomed to call +it the 'roof of silver.' They are wont to roast this mineral, and from +the better part they make metal; from the poorer part they make a +pigment of a kind not to be despised." This pigment was cobalt blue (see +note on p. 112), indicating a considerable confusion of these minerals. +This quotation is the first description of bismuth, and the above text +the first description of bismuth treatment. There is, however, bare +mention of the mineral earlier, in the following single line from the +_Probierbüchlein_ (p. 1): "Jupiter (controls) the ores of tin and +_wismundt_." And it is noted in the _Nützliche Bergbüchlein_ in +association with silver (see Appendix B). + +[60] This _cadmia_ is given in the German translation as _kobelt_. It is +probably the cobalt-arsenic-bismuth minerals common in Saxony. A large +portion of the world's supply of bismuth to-day comes from the cobalt +treatment works near Schneeberg. For further discussion of _cadmia_ see +note on p. 112. + + + + +BOOK X. + + +Questions as to the methods of smelting ores and of obtaining metals I +discussed in Book IX. Following this, I should explain in what manner +the precious metals are parted from the base metals, or on the other +hand the base metals from the precious[1]. Frequently two metals, +occasionally more than two, are melted out of one ore, because in nature +generally there is some amount of gold in silver and in copper, and some +silver in gold, copper, lead, and iron; likewise some copper in gold, +silver, lead, and iron, and some lead in silver; and lastly, some iron +in copper[2]. But I will begin with gold. + +Gold is parted from silver, or likewise the latter from the former, +whether it be mixed by nature or by art, by means of _aqua valens_[3], +and by powders which consist of almost the same things as this _aqua_. +In order to preserve the sequence, I will first speak of the ingredients +of which this _aqua_ is made, then of the method of making it, then of +the manner in which gold is parted from silver or silver from gold. +Almost all these ingredients contain vitriol or alum, which, by +themselves, but much more when joined with saltpetre, are powerful to +part silver from gold. As to the other things that are added to them, +they cannot individually by their own strength and nature separate those +metals, but joined they are very powerful. Since there are many +combinations, I will set out a few. In the first, the use of which is +common and general, there is one _libra_ of vitriol and as much salt, +added to a third of a _libra_ of spring water. The second contains two +_librae_ of vitriol, one of saltpetre, and as much spring or river water +by weight as will pass away whilst the vitriol is being reduced to +powder by the fire. The third consists of four _librae_ of vitriol, two +and a half _librae_ of saltpetre, half a _libra_ of alum, and one and a +half _librae_ of spring water. The fourth consists of two _librae_ of +vitriol, as many _librae_ of saltpetre, one quarter of a _libra_ of +alum, and three-quarters of a _libra_ of spring water. The fifth is +composed of one _libra_ of saltpetre, three _librae_ of alum, half a +_libra_ of brick dust, and three-quarters of a _libra_ of spring water. +The sixth consists of four _librae_ of vitriol, three _librae_ of +saltpetre, one of alum, one _libra_ likewise of stones which when thrown +into a fierce furnace are easily liquefied by fire of the third order, +and one and a half _librae_ of spring water. The seventh is made of two +_librae_ of vitriol, one and a half _librae_ of saltpetre, half a +_libra_ of alum, and one _libra_ of stones which when thrown into a +glowing furnace are easily liquefied by fire of the third order, and +five-sixths of a _libra_ of spring water. The eighth is made of two +_librae_ of vitriol, the same number of _librae_ of saltpetre, one and a +half _librae_ of alum, one _libra_ of the lees of the _aqua_ which parts +gold from silver; and to each separate _libra_ a sixth of urine is +poured over it. The ninth contains two _librae_ of powder of baked +bricks, one _libra_ of vitriol, likewise one _libra_ of saltpetre, a +handful of salt, and three-quarters of a _libra_ of spring water. Only +the tenth lacks vitriol and alum, but it contains three _librae_ of +saltpetre, two _librae_ of stones which when thrown into a hot furnace +are easily liquefied by fire of the third order, half a _libra_ each of +verdigris[4], of _stibium_, of iron scales and filings, and of +asbestos[5], and one and one-sixth _librae_ of spring water. + +All the vitriol from which the _aqua_ is usually made is first reduced +to powder in the following way. It is thrown into an earthen crucible +lined on the inside with litharge, and heated until it melts; then it is +stirred with a copper wire, and after it has cooled it is pounded to +powder. In the same manner saltpetre melted by the fire is pounded to +powder when it has cooled. Some indeed place alum upon an iron plate, +roast it, and make it into powder. + +Although all these _aquae_ cleanse gold concentrates or dust from +impurities, yet there are certain compositions which possess singular +power. The first of these consists of one _libra_ of verdigris and +three-quarters of a _libra_ of vitriol. For each _libra_ there is poured +over it one-sixth of a _libra_ of spring or river water, as to which, +since this pertains to all these compounds, it is sufficient to have +mentioned once for all. The second composition is made from one _libra_ +of each of the following, artificial orpiment, vitriol, lime, alum, ash +which the dyers of wool use, one quarter of a _libra_ of verdigris, and +one and a half _unciae_ of _stibium_. The third consists of three +_librae_ of vitriol, one of saltpetre, half a _libra_ of asbestos, and +half a _libra_ of baked bricks. The fourth consists of one _libra_ of +saltpetre, one _libra_ of alum, and half a _libra_ of sal-ammoniac.[6] + +[Illustration 442 (Nitric Acid Making): A--Furnace. B--Its round hole. +C--Air-holes. D--Mouth of the furnace. E--Draught opening under it. +F--Earthenware crucible. G--Ampulla. H--Operculum. I--Its spout. +K--Other ampulla. L--Basket in which this is usually placed lest it be +broken.] + +The furnace in which _aqua valens_ is made[7] is built of bricks, +rectangular, two feet long and wide, and as many feet high and a half +besides. It is covered with iron plates supported with iron rods; these +plates are smeared on the top with lute, and they have in the centre a +round hole, large enough to hold the earthen vessel in which the glass +ampulla is placed, and on each side of the centre hole are two small +round air-holes. The lower part of the furnace, in order to hold the +burning charcoal, has iron plates at the height of a palm, likewise +supported by iron rods. In the middle of the front there is the mouth, +made for the purpose of putting the fire into the furnace; this mouth is +half a foot high and wide, and rounded at the top, and under it is the +draught opening. Into the earthen vessel set over the hole is placed +clean sand a digit deep, and in it the glass ampulla is set as deeply as +it is smeared with lute. The lower quarter is smeared eight or ten times +with nearly liquid lute, each time to the thickness of a blade, and each +time it is dried again, until it has become as thick as the thumb; this +kind of lute is well beaten with an iron rod, and is thoroughly mixed +with hair or cotton thread, or with wool and salt, that it should not +crackle. The many things of which the compounds are made must not fill +the ampulla completely, lest when boiling they rise into the operculum. +The operculum is likewise made of glass, and is closely joined to the +ampulla with linen, cemented with wheat flour and white of egg moistened +with water, and then lute free from salt is spread over that part of it. +In a similar way the spout of the operculum is joined by linen covered +with lute to another glass ampulla which receives the distilled _aqua_. +A kind of thin iron nail or small wooden peg, a little thicker than a +needle, is fixed in this joint, in order that when air seems necessary +to the artificer distilling by this process he can pull it out; this is +necessary when too much of the vapour has been driven into the upper +part. The four air-holes which, as I have said, are on the top of the +furnace beside the large hole on which the ampulla is placed, are +likewise covered with lute. + +All this preparation having been accomplished in order, and the +ingredients placed in the ampulla, they are gradually heated over +burning charcoal until they begin to exhale vapour and the ampulla is +seen to trickle with moisture. But when this, on account of the rising +of the vapour, turns red, and the _aqua_ distils through the spout of +the operculum, then one must work with the utmost care, lest the drops +should fall at a quicker rate than one for every five movements of the +clock or the striking of its bell, and not slower than one for every +ten; for if it falls faster the glasses will be broken, and if it drops +more slowly the work begun cannot be completed within the definite time, +that is within the space of twenty-four hours. To prevent the first +accident, part of the coals are extracted by means of an iron implement +similar to pincers; and in order to prevent the second happening, small +dry pieces of oak are placed upon the coals, and the substances in the +ampulla are heated with a sharper fire, and the air-holes on the furnace +are re-opened if need arise. As soon as the drops are being distilled, +the glass ampulla which receives them is covered with a piece of linen +moistened with water, in order that the powerful vapour which arises +may be repelled. When the ingredients have been heated and the ampulla +in which they were placed is whitened with moisture, it is heated by a +fiercer fire until all the drops have been distilled[8]. After the +furnace has cooled, the _aqua_ is filtered and poured into a small glass +ampulla, and into the same is put half a _drachma_ of silver[9], which +when dissolved makes the turbid _aqua_ clear. This is poured into the +ampulla containing all the rest of the _aqua_, and as soon as the lees +have sunk to the bottom the _aqua_ is poured off, removed, and reserved +for use. + +Gold is parted from silver by the following method[10]. The alloy, with +lead added to it, is first heated in a cupel until all the lead is +exhaled, and eight ounces of the alloy contain only five _drachmae_ of +copper or at most six, for if there is more copper in it, the silver +separated from the gold soon unites with it again. Such molten silver +containing gold is formed into granules, being stirred by means of a rod +split at the lower end, or else is poured into an iron mould, and when +cooled is made into thin leaves. As the process of making granules from +argentiferous gold demands greater care and diligence than making them +from any other metals, I will now explain the method briefly. The alloy +is first placed in a crucible, which is then covered with a lid and +placed in another earthen crucible containing a few ashes. Then they are +placed in the furnace, and after they are surrounded by charcoal, the +fire is blown by the blast of a bellows, and lest the charcoal fall away +it is surrounded by stones or bricks. Soon afterward charcoal is thrown +over the upper crucible and covered with live coals; these again are +covered with charcoal, so that the crucible is surrounded and covered on +all sides with it. It is necessary to heat the crucibles with charcoal +for the space of half an hour or a little longer, and to provide that +there is no deficiency of charcoal, lest the alloy become chilled; after +this the air is blown in through the nozzle of the bellows, that the +gold may begin to melt. Soon afterward it is turned round, and a test is +quickly taken to see whether it be melted, and if it is melted, fluxes +are thrown into it; it is advisable to cover up the crucible again +closely that the contents may not be exhaled. The contents are heated +together for as long as it would take to walk fifteen paces, and then +the crucible is seized with tongs and the gold is emptied into an oblong +vessel containing very cold water, by pouring it slowly from a height so +that the granules will not be too big; in proportion as they are +lighter, more fine and more irregular, the better they are, therefore +the water is frequently stirred with a rod split into four parts from +the lower end to the middle. + +The leaves are cut into small pieces, and they or the silver granules +are put into a glass ampulla, and the _aqua_ is poured over them to a +height of a digit above the silver. The ampulla is covered with a +bladder or with waxed linen, lest the contents exhale. Then it is heated +until the silver is dissolved, the indication of which is the bubbling +of the _aqua_. The gold remains in the bottom, of a blackish colour, and +the silver mixed with the _aqua_ floats above. Some pour the latter into +a copper bowl and pour into it cold water, which immediately congeals +the silver; this they take out and dry, having poured off the +_aqua_[11]. They heat the dried silver in an earthenware crucible until +it melts, and when it is melted they pour it into an iron mould. + +The gold which remains in the ampulla they wash with warm water, filter, +dry, and heat in a crucible with a little _chrysocolla_ which is called +borax, and when it is melted they likewise pour it into an iron mould. + +Some workers, into an ampulla which contains gold and silver and the +_aqua_ which separates them, pour two or three times as much of this +_aqua valens_ warmed, and into the same ampulla or into a dish into +which all is poured, throw fine leaves of black lead and copper; by this +means the gold adheres to the lead and the silver to the copper, and +separately the lead from the gold, and separately the copper from the +silver, are parted in a cupel. But no method is approved by us which +loses the _aqua_ used to part gold from silver, for it might be used +again[12]. + +[Illustration 446 (Parting precious metals with nitric acid): +A--Ampullae arranged in the vessels. B--An ampulla standing upright +between iron rods. C--Ampullae placed in the sand which is contained in +a box, the spouts of which reach from the opercula into ampullae placed +under them. D--Ampullae likewise placed in sand which is contained in a +box, of which the spouts from the opercula extend crosswise into +ampullae placed under them. E--Other ampullae receiving the distilled +_aqua_ and likewise arranged in sand contained in the lower boxes. +F--Iron tripod, in which the ampulla is usually placed when there are +not many particles of gold to be parted from the silver. G--Vessel.] + +A glass ampulla, which bulges up inside at the bottom like a cone, is +covered on the lower part of the outside with lute in the way explained +above, and into it is put silver bullion weighing three and a half Roman +_librae_. The _aqua_ which parts the one from the other is poured into +it, and the ampulla is placed in sand contained in an earthen vessel, or +in a box, that it may be warmed with a gentle fire. Lest the _aqua_ +should be exhaled, the top of the ampulla is plastered on all sides with +lute, and it is covered with a glass operculum, under whose spout is +placed another ampulla which receives the distilled drops; this receiver +is likewise arranged in a box containing sand. When the contents are +heated it reddens, but when the redness no longer appears to increase, +it is taken out of the vessel or box and shaken; by this motion the +_aqua_ becomes heated again and grows red; if this is done two or three +times before other _aqua_ is added to it, the operation is sooner +concluded, and much less _aqua_ is consumed. When the first charge has +all been distilled, as much silver as at first is again put into the +ampulla, for if too much were put in at once, the gold would be parted +from it with difficulty. Then the second _aqua_ is poured in, but it is +warmed in order that it and the ampulla may be of equal temperature, so +that the latter may not be cracked by the cold; also if a cold wind +blows on it, it is apt to crack. Then the third _aqua_ is poured in, and +also if circumstances require it, the fourth, that is to say more _aqua_ +and again more is poured in until the gold assumes the colour of burned +brick. The artificer keeps in hand two _aquae_, one of which is stronger +than the other; the stronger is used at first, then the less strong, +then at the last again the stronger. When the gold becomes of a reddish +yellow colour, spring water is poured in and heated until it boils. The +gold is washed four times and then heated in the crucible until it +melts. The water with which it was washed is put back, for there is a +little silver in it; for this reason it is poured into an ampulla and +heated, and the drops first distilled are received by one ampulla, while +those which come later, that is to say when the operculum begins to get +red, fall into another. This latter _aqua_ is useful for testing the +gold, the former for washing it; the former may also be poured over the +ingredients from which the _aqua valens_ is made. + +The _aqua_ that was first distilled, which contains the silver, is +poured into an ampulla wide at the base, the top of which is also +smeared with lute and covered by an operculum, and is then boiled as +before in order that it may be separated from the silver. If there be so +much _aqua_ that (when boiled) it rises into the operculum, there is +put into the ampulla one lozenge or two; these are made of soap, cut +into small pieces and mixed together with powdered argol, and then +heated in a pot over a gentle fire; or else the contents are stirred +with a hazel twig split at the bottom, and in both cases the _aqua_ +effervesces, and soon after again settles. When the powerful vapour +appears, the _aqua_ gives off a kind of oil, and the operculum becomes +red. But, lest the vapours should escape from the ampulla and the +operculum in that part where their mouths communicate, they are entirely +sealed all round. The _aqua_ is boiled continually over a fiercer fire, +and enough charcoal must be put into the furnace so that the live coals +touch the vessel. The ampulla is taken out as soon as all the _aqua_ has +been distilled, and the silver, which is dried by the heat of the fire, +alone remains in it; the silver is shaken out and put in an earthenware +crucible, and heated until it melts. The molten glass is extracted with +an iron rod curved at the lower end, and the silver is made into cakes. +The glass extracted from the crucible is ground to powder, and to this +are added litharge, argol, glass-galls, and saltpetre, and they are +melted in an earthen crucible. The button that settles is transferred to +the cupel and re-melted. + +If the silver was not sufficiently dried by the heat of the fire, that +which is contained in the upper part of the ampulla will appear black; +this when melted will be consumed. When the lute, which was smeared +round the lower part of the ampulla, has been removed, it is placed in +the crucible and is re-melted, until at last there is no more appearance +of black[13]. + +If to the first _aqua_ the other which contains silver is to be added, +it must be poured in before the powerful vapours appear, and the _aqua_ +gives off the oily substance, and the operculum becomes red; for he who +pours in the _aqua_ after the vapour appears causes a loss, because the +_aqua_ generally spurts out and the glass breaks. If the ampulla breaks +when the gold is being parted from the silver or the silver from the +_aqua_, the _aqua_ will be absorbed by the sand or the lute or the +bricks, whereupon, without any delay, the red hot coals should be taken +out of the furnace and the fire extinguished. The sand and bricks after +being crushed should be thrown into a copper vessel, warm water should +be poured over them, and they should be put aside for the space of +twelve hours; afterward the water should be strained through a canvas, +and the canvas, since it contains silver, should be dried by the heat of +the sun or the fire, and then placed in an earthen crucible and heated +until the silver melts, this being poured out into an iron mould. The +strained water should be poured into an ampulla and separated from the +silver, of which it contains a minute portion; the sand should be mixed +with litharge, glass-galls, argol, saltpetre, and salt, and heated in an +earthen crucible. The button which settles at the bottom should be +transferred to a cupel, and should be re-melted, in order that the lead +may be separated from the silver. The lute, with lead added, should be +heated in an earthen crucible, then re-melted in a cupel. + +We also separate silver from gold by the same method when we assay them. +For this purpose the alloy is first rubbed against a touchstone, in +order to learn what proportion of silver there is in it; then as much +silver as is necessary is added to the argentiferous gold, in a _bes_ of +which there must be less than a _semi-uncia_ or a _semi-uncia_ and a +_sicilicus_[14] of copper. After lead has been added, it is melted in a +cupel until the lead and the copper have exhaled, then the alloy of gold +with silver is flattened out, and little tubes are made of the leaves; +these are put into a glass ampulla, and strong _aqua_ is poured over +them two or three times. The tubes after this are absolutely pure, with +the exception of only a quarter of a _siliqua_, which is silver; for +only this much silver remains in eight _unciae_ of gold[15]. + +As great expense is incurred in parting the metals by the methods that +I have explained, as night vigils are necessary when _aqua valens_ is +made, and as generally much labour and great pains have to be expended +on this matter, other methods for parting have been invented by clever +men, which are less costly, less laborious, and in which there is less +loss if through carelessness an error is made. There are three methods, +the first performed with sulphur, the second with antimony, the third by +means of some compound which consists of these or other ingredients. + +[Illustration 449 (Parting precious metals with sulphur): A--Pot. +B--Circular fire. C--Crucibles. D--Their lids. E--Lid of the pot. +F--Furnace. G--Iron rod.] + +In the first method,[16] the silver containing some gold is melted in a +crucible and made into granules. For every _libra_ of granules, there is +taken a sixth of a _libra_ and a _sicilicus_ of sulphur (not exposed to +the fire); this, when crushed, is sprinkled over the moistened granules, +and then they are put into a new earthen pot of the capacity of four +_sextarii_, or into several of them if there is an abundance of +granules. The pot, having been filled, is covered with an earthen lid +and smeared over, and placed within a circle of fire set one and a half +feet distant from the pot on all sides, in order that the sulphur added +to the silver should not be distilled when melted. The pot is opened, +the black-coloured granules are taken out, and afterward thirty-three +_librae_ of these granules are placed in an earthen crucible, if it has +such capacity. For every _libra_ of silver granules, weighed before they +were sprinkled with sulphur, there is weighed out also a sixth of a +_libra_ and a _sicilicus_ of copper, if each _libra_ consists either of +three-quarters of a _libra_ of silver and a quarter of a _libra_ of +copper, or of three-quarters of a _libra_ and a _semi-uncia_ of silver +and a sixth of a _libra_ and a _semi-uncia_ of copper. If, however, the +silver contains five-sixths of a _libra_ of silver and a sixth of a +_libra_ of copper, or five-sixths of a _libra_ and a _semi-uncia_ of +silver and an _uncia_ and a half of copper, then there are weighed out a +quarter of a _libra_ of copper granules. If a _libra_ contains +eleven-twelfths of a _libra_ of silver and one _uncia_ of copper, or +eleven-twelfths and a _semi-uncia_ of silver and a _semi-uncia_ of +copper, then are weighed out a quarter of a _libra_ and a _semi-uncia_ +and a _sicilicus_ of copper granules. Lastly, if there is only pure +silver, then as much as a third of a _libra_ and a _semi-uncia_ of +copper granules are added. Half of these copper granules are added soon +afterward to the black-coloured silver granules. The crucible should be +tightly covered and smeared over with lute, and placed in a furnace, +into which the air is drawn through the draught-holes. As soon as the +silver is melted, the crucible is opened, and there is placed in it a +heaped ladleful more of granulated copper, and also a heaped ladleful of +a powder which consists of equal parts of litharge, of granulated lead, +of salt, and of glass-galls; then the crucible is again covered with the +lid. When the copper granules are melted, more are put in, together with +the powder, until all have been put in. + +A little of the regulus is taken from the crucible, but not from the +gold lump which has settled at the bottom, and a _drachma_ of it is put +into each of the cupels, which contain an _uncia_ of molten lead; there +should be many of these cupels. In this way half a _drachma_ of silver +is made. As soon as the lead and copper have been separated from the +silver, a third of it is thrown into a glass ampulla, and _aqua valens_ +is poured over it. By this method is shown whether the sulphur has +parted all the gold from the silver, or not. If one wishes to know the +size of the gold lump which has settled at the bottom of the crucible, +an iron rod moistened with water is covered with chalk, and when the rod +is dry it is pushed down straight into the crucible, and the rod remains +bright to the height of the gold lump; the remaining part of the rod is +coloured black by the regulus, which adheres to the rod if it is not +quickly removed. + +If when the rod has been extracted the gold is observed to be +satisfactorily parted from the silver, the regulus is poured out, the +gold button is taken out of the crucible, and in some clean place the +regulus is chipped off from it, although it usually flies apart. The +lump itself is reduced to granules, and for every _libra_ of this gold +they weigh out a quarter of a _libra_ each of crushed sulphur and of +granular copper, and all are placed together in an earthen crucible, not +into a pot. When they are melted, in order that the gold may more +quickly settle at the bottom, the powder which I have mentioned is +added. + +Although minute particles of gold appear to scintillate in the regulus +of copper and silver, yet if all that are in a _libra_ do not weigh as +much as a single sesterce, then the sulphur has satisfactorily parted +the gold from the silver; but if it should weigh a sesterce or more, +then the regulus is thrown back again into the earthen crucible, and it +is not advantageous to add sulphur, but only a little copper and powder, +by which method a gold lump is again made to settle at the bottom; and +this one is added to the other button which is not rich in gold. + +When gold is parted from sixty-six _librae_ of silver, the silver, +copper, and sulphur regulus weighs one hundred and thirty-two _librae_. +To separate the copper from the silver we require five hundred _librae_ +of lead, more or less, with which the regulus is melted in the second +furnace. In this manner litharge and hearth-lead are made, which are +re-smelted in the first furnace. The cakes that are made from these are +placed in the third furnace, so that the lead may be separated from the +copper and used again, for it contains very little silver. The crucibles +and their covers are crushed, washed, and the sediment is melted +together with litharge and hearth-lead. + +Those who wish to separate all the silver from the gold by this method +leave one part of gold to three of silver, and then reduce the alloy to +granules. Then they place it in an ampulla, and by pouring _aqua valens_ +over it, part the gold from the silver, which process I explained in +Book VII. + +If sulphur from the lye with which _sal artificiosus_ is made, is strong +enough to float an egg thrown into it, and is boiled until it no longer +emits fumes, and melts when placed upon glowing coals, then, if such +sulphur is thrown into the melted silver, it parts the gold from it. + +[Illustration 453 (Parting precious metals with antimony): A--Furnace in +which the air is drawn in through holes. B--Goldsmith's forge. +C--Earthen crucibles. D--Iron pots. E--Block.] + +Silver is also parted from gold by means of _stibium_[17]. If in a _bes +of_ gold there are seven, or six, or five double _sextulae_ of silver, +then three parts of _stibium_ are added to one part of gold; but in +order that the _stibium_ should not consume the gold, it is melted with +copper in a red hot earthen crucible. If the gold contains some portion +of copper, then to eight _unciae_ of _stibium_ a _sicilicus_ of copper +is added; and if it contains no copper, then half an _uncia_, because +copper must be added to _stibium_ in order to part gold from silver. The +gold is first placed in a red hot earthen crucible, and when melted it +swells, and a little _stibium_ is added to it lest it run over; in a +short space of time, when this has melted, it likewise again swells, and +when this occurs it is advisable to put in all the remainder of the +_stibium_, and to cover the crucible with a lid, and then to heat the +mixture for the time required to walk thirty-five paces. Then it is at +once poured out into an iron pot, wide at the top and narrow at the +bottom, which was first heated and smeared over with tallow or wax, and +set on an iron or wooden block. It is shaken violently, and by this +agitation the gold lump settles to the bottom, and when the pot has +cooled it is tapped loose, and is again melted four times in the same +way. But each time a less weight of _stibium_ is added to the gold, +until finally only twice as much _stibium_ is added as there is gold, or +a little more; then the gold lump is melted in a cupel. The _stibium_ is +melted again three or four times in an earthen crucible, and each time a +gold lump settles, so that there are three or four gold lumps, and these +are all melted together in a cupel. + +To two _librae_ and a half of such _stibium_ are added two _librae_ of +argol and one _libra_ of glass-galls, and they are melted in an earthen +crucible, where a lump likewise settles at the bottom; this lump is +melted in the cupel. Finally, the _stibium_ with a little lead added, is +melted in the cupel, in which, after all the rest has been consumed by +the fire, the silver alone remains. If the _stibium_ is not first melted +in an earthen crucible with argol and glass-galls, before it is melted +in the cupel, part of the silver is consumed, and is absorbed by the ash +and powder of which the cupel is made. + +The crucible in which the gold and silver alloy are melted with +_stibium_, and also the cupel, are placed in a furnace, which is usually +of the kind in which the air is drawn in through holes; or else they +are placed in a goldsmith's forge. + +Just as _aqua valens_ poured over silver, from which the sulphur has +parted the gold, shows us whether all has been separated or whether +particles of gold remain in the silver; so do certain ingredients, if +placed in the pot or crucible "alternately" with the gold, from which +the silver has been parted by _stibium_, and heated, show us whether all +have been separated or not. + +We use cements[18] when, without _stibium_, we part silver or copper or +both so ingeniously and admirably from gold. There are various cements. +Some consist of half a _libra_ of brick dust, a quarter of a _libra_ of +salt, an _uncia_ of saltpetre, half an _uncia_ of sal-ammoniac, and half +an _uncia_ of rock salt. The bricks or tiles from which the dust is made +must be composed of fatty clays, free from sand, grit, and small stones, +and must be moderately burnt and very old. + +Another cement is made of a _bes_ of brick dust, a third of rock salt, +an _uncia_ of saltpetre, and half an _uncia_ of refined salt. Another +cement is made of a _bes_ of brick dust, a quarter of refined salt, one +and a half _unciae_ of saltpetre, an _uncia_ of sal-ammoniac, and half +an _uncia_ of rock salt. Another has one _libra_ of brick dust, and half +a _libra_ of rock salt, to which some add a sixth of a _libra_ and a +_sicilicus_ of vitriol. Another is made of half a _libra_ of brick dust, +a third of a _libra_ of rock salt, an _uncia_ and a half of vitriol, and +one _uncia_ of saltpetre. Another consists of a _bes_ of brick dust, a +third of refined salt, a sixth of white vitriol[19], half an _uncia_ of +verdigris, and likewise half an _uncia_ of saltpetre. Another is made of +one and a third _librae_ of brick dust, a _bes_ of rock salt, a sixth of +a _libra_ and half an _uncia_ of sal-ammoniac, a sixth and half an +_uncia_ of vitriol, and a sixth of saltpetre. Another contains a _libra_ +of brick dust, a third of refined salt, and one and a half _unciae_ of +vitriol. + +Those ingredients above are peculiar to each cement, but what follows +is common to all. Each of the ingredients is first separately crushed to +powder; the bricks are placed on a hard rock or marble, and crushed with +an iron implement; the other things are crushed in a mortar with a +pestle; each is separately passed through a sieve. Then they are all +mixed together, and are moistened with vinegar in which a little +sal-ammoniac has been dissolved, if the cement does not contain any. But +some workers, however, prefer to moisten the gold granules or gold-leaf +instead. + +The cement should be placed, alternately with the gold, in new and clean +pots in which no water has ever been poured. In the bottom the cement is +levelled with an iron implement, and afterward the gold granules or +leaves are placed one against the other, so that they may touch it on +all sides; then, again, a handful of the cement, or more if the pots are +large, is thrown in and levelled with an iron implement; the granules +and leaves are laid over this in the same manner, and this is repeated +until the pot is filled. Then it is covered with a lid, and the place +where they join is smeared over with artificial lute, and when this is +dry the pots are placed in the furnace. + +[Illustration 455 (Parting precious metals by cementation): A--Furnace. +B--Pot. C--Lid. D--Air-holes.] + +The furnace has three chambers, the lowest of which is a foot high; into +this lowest chamber the air penetrates through an opening, and into it +the ashes fall from the burnt wood, which is supported by iron rods, +arranged to form a grating. The middle chamber is two feet high, and the +wood is pushed in through its mouth. The wood ought to be oak, holmoak, +or turkey-oak, for from these the slow and lasting fire is made which is +necessary for this operation. The upper chamber is open at the top so +that the pots, for which it has the depth, may be put into it; the floor +of this chamber consists of iron rods, so strong that they may bear the +weight of the pots and the heat of the fire; they are sufficiently far +apart that the fire may penetrate well and may heat the pots. The pots +are narrow at the bottom, so that the fire entering into the space +between them may heat them; at the top the pots are wide, so that they +may touch and hold back the heat of the fire. The upper part of the +furnace is closed in with bricks not very thick, or with tiles and lute, +and two or three air-holes are left, through which the fumes and flames +may escape. + +The gold granules or leaves and the cement, alternately placed in the +pots, are heated by a gentle fire, gradually increasing for twenty-four +hours, if the furnace was heated for two hours before the full pots were +stood in it, and if this was not done, then for twenty-six hours. The +fire should be increased in such a manner that the pieces of gold and +the cement, in which is the potency to separate the silver and copper +from the gold, may not melt, for in this case the labour and cost will +be spent in vain; therefore, it is ample to have the fire hot enough +that the pots always remain red. After so many hours all the burning +wood should be drawn out of the furnace. Then the refractory bricks or +tiles are removed from the top of the furnace, and the glowing pots are +taken out with the tongs. The lids are removed, and if there is time it +is well to allow the gold to cool by itself, for then there is less +loss; but if time cannot be spared for that operation, the pieces of +gold are immediately placed separately into a wooden or bronze vessel of +water and gradually quenched, lest the cement which absorbs the silver +should exhale it. The pieces of gold, and the cement adhering to them, +when cooled or quenched, are rolled with a little mallet so as to crush +the lumps and free the gold from the cement. Then they are sifted by a +fine sieve, which is placed over a bronze vessel; in this manner the +cement containing the silver or the copper or both, falls from the sieve +into the bronze vessel, and the gold granules or leaves remain on it. +The gold is placed in a vessel and again rolled with the little mallet, +so that it may be cleansed from the cement which absorbs silver and +copper. + +The particles of cement, which have dropped through the holes of the +sieve into the bronze vessel, are washed in a bowl, over a wooden tub, +being shaken about with the hands, so that the minute particles of gold +which have fallen through the sieve may be separated. These are again +washed in a little vessel, with warm water, and scrubbed with a piece of +wood or a twig broom, that the moistened cement may be detached. +Afterward all the gold is again washed with warm water, and collected +with a bristle brush, and should be washed in a copper full of holes, +under which is placed a little vessel. Then it is necessary to put the +gold on an iron plate, under which is a vessel, and to wash it with +warm water. Finally, it is placed in a bowl, and, when dry, the granules +or leaves are rubbed against a touchstone at the same time as a +touch-needle, and considered carefully as to whether they be pure or +alloyed. If they are not pure enough, the granules or the leaves, +together with the cement which attracts silver and copper, are arranged +alternately in layers in the same manner, and again heated; this is done +as often as is necessary, but the last time it is heated as many hours +as are required to cleanse the gold. + +Some people add another cement to the granules or leaves. This cement +lacks the ingredients of metalliferous origin, such as verdigris and +vitriol, for if these are in the cement, the gold usually takes up a +little of the base metal; or if it does not do this, it is stained by +them. For this reason some very rightly never make use of cements +containing these things, because brick dust and salt alone, especially +rock salt, are able to extract all the silver and copper from the gold +and to attract it to themselves. + +It is not necessary for coiners to make absolutely pure gold, but to +heat it only until such a fineness is obtained as is needed for the gold +money which they are coining. + +The gold is heated, and when it shows the necessary golden yellow colour +and is wholly pure, it is melted and made into bars, in which case they +are either prepared by the coiners with _chrysocolla_, which is called +by the Moors borax, or are prepared with salt of lye made from the ashes +of ivy or of other salty herbs. + +The cement which has absorbed silver or copper, after water has been +poured over it, is dried and crushed, and when mixed with hearth-lead +and de-silverized lead, is smelted in the blast furnace. The alloy of +silver and lead, or of silver and copper and lead, which flows out, is +again melted in the cupellation furnace, in order that the lead and +copper may be separated from the silver. The silver is finally +thoroughly purified in the refining furnace, and in this practical +manner there is no silver lost, or only a minute quantity. + +There are besides this, certain other cements[20] which part gold from +silver, composed of sulphur, _stibium_ and other ingredients. One of +these compounds consists of half an _uncia_ of vitriol dried by the heat +of the fire and reduced to powder, a sixth of refined salt, a third of +_stibium_, half a _libra_ of prepared sulphur (not exposed to the +fire), one _sicilicus_ of glass, likewise one _sicilicus_ of saltpetre, +and a _drachma_ of sal-ammoniac.[21] The sulphur is prepared as follows: +it is first crushed to powder, then it is heated for six hours in sharp +vinegar, and finally poured into a vessel and washed with warm water; +then that which settles at the bottom of the vessel is dried. To refine +the salt it is placed in river water and boiled, and again evaporated. +The second compound contains one _libra_ of sulphur (not exposed to +fire) and two _librae_ of refined salt. The third compound is made from +one _libra_ of sulphur (not exposed to the fire), half a _libra_ of +refined salt, a quarter of a _libra_ of sal-ammoniac, and one _uncia_ of +red-lead. The fourth compound consists of one _libra_ each of refined +salt, sulphur (not exposed to the fire) and argol, and half a _libra_ of +_chrysocolla_ which the Moors call borax. The fifth compound has equal +proportions of sulphur (not exposed to the fire), sal-ammoniac, +saltpetre, and verdigris. + +The silver which contains some portion of gold is first melted with lead +in an earthen crucible, and they are heated together until the silver +exhales the lead. If there was a _libra_ of silver, there must be six +_drachmae_ of lead. Then the silver is sprinkled with two _unciae_ of +that powdered compound and is stirred; afterward it is poured into +another crucible, first warmed and lined with tallow, and then violently +shaken. The rest is performed according to the process I have already +explained. + +Gold may be parted without injury from silver goblets and from other +gilt vessels and articles[22], by means of a powder, which consists of +one part of sal-ammoniac and half a part of sulphur. The gilt goblet or +other article is smeared with oil, and the powder is dusted on; the +article is seized in the hand, or with tongs, and is carried to the fire +and sharply tapped, and by this means the gold falls into water in +vessels placed underneath, while the goblet remains uninjured. + +Gold is also parted from silver on gilt articles by means of +quicksilver. This is poured into an earthen crucible, and so warmed by +the fire that the finger can bear the heat when dipped into it; the +silver-gilt objects are placed in it, and when the quicksilver adheres +to them they are taken out and placed on a dish, into which, when +cooled, the gold falls, together with the quicksilver. Again and +frequently the same silver-gilt object is placed in heated quicksilver, +and the same process is continued until at last no more gold is visible +on the object; then the object is placed in the fire, and the +quicksilver which adheres to it is exhaled. Then the artificer takes a +hare's foot, and brushes up into a dish the quicksilver and the gold +which have fallen together from the silver article, and puts them into +a cloth made of woven cotton or into a soft leather; the quicksilver is +squeezed through one or the other into another dish.[23] The gold +remains in the cloth or the leather, and when collected is placed in a +piece of charcoal hollowed out, and is heated until it melts, and a +little button is made from it. This button is heated with a little +_stibium_ in an earthen crucible and poured out into another little +vessel, by which method the gold settles at the bottom, and the +_stibium_ is seen to be on the top; then the work is completed. Finally, +the gold button is put in a hollowed-out brick and placed in the fire, +and by this method the gold is made pure. By means of the above methods +gold is parted from silver and also silver from gold. + +Now I will explain the methods used to separate copper from gold[24]. +The salt which we call _sal-artificiosus_,[25] is made from a _libra_ +each of vitriol, alum, saltpetre, and sulphur not exposed to the fire, +and half a _libra_ of sal-ammoniac; these ingredients when crushed are +heated with one part of lye made from the ashes used by wool dyers, one +part of unslaked lime, and four parts of beech ashes. The ingredients +are boiled in the lye until the whole has been dissolved. Then it is +immediately dried and kept in a hot place, lest it turn into oil; and +afterward when crushed, a _libra_ of lead-ash is mixed with it. With +each _libra_ of this powdered compound one and a half _unciae_ of the +copper is gradually sprinkled into a hot crucible, and it is stirred +rapidly and frequently with an iron rod. When the crucible has cooled +and been broken up, the button of gold is found. + +The second method for parting is the following. Two _librae_ of sulphur +not exposed to the fire, and four _librae_ of refined salt are crushed +and mixed; a sixth of a _libra_ and half an _uncia_ of this powder is +added to a _bes_ of granules made of lead, and twice as much copper +containing gold; they are heated together in an earthen crucible until +they melt. When cooled, the button is taken out and purged of slag. From +this button they again make granules, to a third of a _libra_ of which +is added half a _libra_ of that powder of which I have spoken, and they +are placed in alternate layers in the crucible; it is well to cover the +crucible and to seal it up, and afterward it is heated over a gentle +fire until the granules melt. Soon afterward, the crucible is taken off +the fire, and when it is cool the button is extracted. From this, when +purified and again melted down, the third granules are made, to which, +if they weigh a sixth of a _libra_, is added one half an _uncia_ and a +_sicilicus_ of the powder, and they are heated in the same manner, and +the button of gold settles at the bottom of the crucible. + +The third method is as follows. From time to time small pieces of +sulphur, enveloped in or mixed with wax, are dropped into six _librae_ +of the molten copper, and consumed; the sulphur weighs half an _uncia_ +and a _sicilicus_. Then one and a half _sicilici_ of powdered saltpetre +are dropped into the same copper and likewise consumed; then again half +an _uncia_ and a _sicilicus_ of sulphur enveloped in wax; afterward one +and a half _sicilici_ of lead-ash enveloped in wax, or of minium made +from red-lead. Then immediately the copper is taken out, and to the gold +button, which is now mixed with only a little copper, they add _stibium_ +to double the amount of the button; these are heated together until the +_stibium_ is driven off; then the button, together with lead of half the +weight of the button, are heated in a cupel. Finally, the gold is taken +out of this and quenched, and if there is a blackish colour settled in +it, it is melted with a little of the _chrysocolla_ which the Moors call +borax; if too pale, it is melted with _stibium_, and acquires its own +golden-yellow colour. There are some who take out the molten copper with +an iron ladle and pour it into another crucible, whose aperture is +sealed up with lute, and they place it over glowing charcoal, and when +they have thrown in the powders of which I have spoken, they stir the +whole mass rapidly with an iron rod, and thus separate the gold from the +copper; the former settles at the bottom of the crucible, the latter +floats on the top. Then the aperture of the crucible is opened with the +red-hot tongs, and the copper runs out. The gold which remains is +re-heated with _stibium_, and when this is exhaled the gold is heated +for the third time in a cupel with a fourth part of lead, and then +quenched. + +The fourth method is to melt one and a third _librae_ of the copper with +a sixth of a _libra_ of lead, and to pour it into another crucible +smeared on the inside with tallow or gypsum; and to this is added a +powder consisting of half an _uncia_ each of prepared sulphur, +verdigris, and saltpetre, and an _uncia_ and a half of _sal coctus_. The +fifth method consists of placing in a crucible one _libra_ of the copper +and two _librae_ of granulated lead, with one and a half _unciae_ of +_sal-artificiosus_; they are at first heated over a gentle fire and then +over a fiercer one. The sixth method consists in heating together a +_bes_ of the copper and one-sixth of a _libra_ each of sulphur, salt, +and _stibium_. The seventh method consists of heating together a _bes_ +of the copper and one-sixth each of iron scales and filings, salt, +_stibium_, and glass-galls. The eighth method consists of heating +together one _libra_ of the copper, one and a half _librae_ of sulphur, +half a _libra_ of verdigris, and a _libra_ of refined salt. The ninth +method consists of placing in one _libra_ of the molten copper as much +pounded sulphur, not exposed to the fire, and of stirring it rapidly +with an iron rod; the lump is ground to powder, into which quicksilver +is poured, and this attracts to itself the gold. + +Gilded copper articles are moistened with water and placed on the fire, +and when they are glowing they are quenched with cold water, and the +gold is scraped off with a brass rod. By these practical methods gold is +separated from copper. + +Either copper or lead is separated from silver by the methods which I +will now explain.[26] This is carried on in a building near by the +works, or in the works in which the gold or silver ores or alloys are +smelted. The middle wall of such a building is twenty-one feet long and +fifteen feet high, and from this a front wall is distant fifteen feet +toward the river; the rear wall is nineteen feet distant, and both +these walls are thirty-six feet long and fourteen feet high; a +transverse wall extends from the end of the front wall to the end of the +rear wall; then fifteen feet back a second transverse wall is built out +from the front wall to the end of the middle wall. In that space which +is between those two transverse walls are set up the stamps, by means of +which the ores and the necessary ingredients for smelting are broken up. +From the further end of the front wall, a third transverse wall leads to +the other end of the middle wall, and from the same to the end of the +rear wall. The space between the second and third transverse walls, and +between the rear and middle long walls, contains the cupellation +furnace, in which lead is separated from gold or silver. The vertical +wall of its chimney is erected upon the middle wall, and the sloping +chimney-wall rests on the beams which extend from the second transverse +wall to the third; these are so located that they are at a distance of +thirteen feet from the middle long wall and four from the rear wall, and +they are two feet wide and thick. From the ground up to the roof-beams +is twelve feet, and lest the sloping chimney-wall should fall down, it +is partly supported by means of many iron rods, and partly by means of a +few tie-beams covered with lute, which extend from the small beams of +the sloping chimney-wall to the beams of the vertical chimney-wall. The +rear roof is arranged in the same way as the roof of the works in which +ore is smelted. In the space between the middle and the front long walls +and between the second[27] and the third transverse walls are the +bellows, the machinery for depressing and the instrument for raising +them. A drum on the axle of a water-wheel has rundles which turn the +toothed drum of an axle, whose long cams depress the levers of the +bellows, and also another toothed drum on an axle, whose cams raise the +tappets of the stamps, but in the opposite direction. So that if the +cams which depress the levers of the bellows turn from north to south, +the cams of the stamps turn from south to north. + +[Illustration 468 (Cupellation Furnace): A--Rectangular stones. +B--Sole-stone. C--Air-holes. D--Internal walls. E--Dome. F--Crucible. +G--Bands. H--Bars. I--Apertures in the dome. K--Lid of the dome. +L--Rings. M--Pipes. N--Valves. O--Chains.] + +Lead is separated from gold or silver in a cupellation furnace, of which +the structure consists of rectangular stones, of two interior walls of +which the one intersects the other transversely, of a round sole, and of +a dome. Its crucible is made from powder of earth and ash; but I will +first speak of the structure and also of the rectangular stones. A +circular wall is built four feet and three palms high, and one foot +thick; from the height of two feet and three palms from the bottom, the +upper part of the interior is cut away to the width of one palm, so that +the stone sole may rest upon it. There are usually as many as fourteen +stones; on the outside they are a foot and a palm wide, and on the +inside narrower, because the inner circle is much smaller than the +outer; if the stones are wider, fewer are required, if narrower more; +they are sunk into the earth to a depth of a foot and a palm. At the top +each one is joined to the next by an iron staple, the points of which +are embedded in holes, and into each hole is poured molten lead. This +stone structure has six air-holes near the ground, at a height of a foot +above the ground; they are two feet and a palm from the bottom of the +stones; each of these air-holes is in two stones, and is two palms high, +and a palm and three digits wide. One of them is on the right side, +between the wall which protects the main wall from the fire, and the +channel through which the litharge flows out of the furnace crucible; +the other five air-holes are distributed all round at equal distances +apart; through these escapes the moisture which the earth exhales when +heated, and if it were not for these openings the crucible would absorb +the moisture and be damaged. In such a case a lump would be raised, like +that which a mole throws up from the earth, and the ash would float on +the top, and the crucible would absorb the silver-lead alloy; there are +some who, because of this, make the rear part of the structure entirely +open. The two inner walls, of which one intersects the other, are built +of bricks, and are a brick in thickness. There are four air-holes in +these, one in each part, which are about one digit's breadth higher and +wider than the others. Into the four compartments is thrown a +wheelbarrowful of slag, and over this is placed a large wicker basket +full of charcoal dust. These walls extend a cubit above the ground, and +on these, and on the ledge cut in the rectangular stones, is placed the +stone sole; this sole is a palm and three digits thick, and on all sides +touches the rectangular stones; if there are any cracks in it they are +filled up with fragments of stone or brick. The front part of the sole +is sloped so that a channel can be made, through which the litharge +flows out. Copper plates are placed on this part of the sole-stone so +that the silver-lead or other alloy may be more rapidly heated. + +A dome which has the shape of half a sphere covers the crucible. It +consists of iron bands and of bars and of a lid. There are three bands, +each about a palm wide and a digit thick; the lowest is at a distance of +one foot from the middle one, and the middle one a distance of two feet +from the upper one. Under them are eighteen iron bars fixed by iron +rivets; these bars are of the same width and thickness as the bands, and +they are of such a length, that curving, they reach from the lower band +to the upper, that is two feet and three palms long, while the dome is +only one foot and three palms high. All the bars and bands of the dome +have iron plates fastened on the underside with iron wire. In addition, +the dome has four apertures; the rear one, which is situated opposite +the channel through which the litharge flows out, is two feet wide at +the bottom; toward the top, since it slopes gently, it is narrower, +being a foot, three palms, and a digit wide; there is no bar at this +place, for the aperture extends from the upper band to the middle one, +but not to the lower one. The second aperture is situated above the +channel, is two and a half feet wide at the bottom, and two feet and a +palm at the top; and there is likewise no bar at this point; indeed, not +only does the bar not extend to the lower band, but the lower band +itself does not extend over this part, in order that the master can draw +the litharge out of the crucible. There are besides, in the wall which +protects the principal wall against the heat, near where the nozzles of +the bellows are situated, two apertures, three palms wide and about a +foot high, in the middle of which two rods descend, fastened on the +inside with plates. Near these apertures are placed the nozzles of the +bellows, and through the apertures extend the pipes in which the nozzles +of the bellows are set. These pipes are made of iron plates rolled up; +they are two palms three digits long, and their inside diameter is three +and a half digits; into these two pipes the nozzles of the bellows +penetrate a distance of three digits from their valves. The lid of the +dome consists of an iron band at the bottom, two digits wide, and of +three curved iron bars, which extend from one point on the band to the +point opposite; they cross each other at the top, where they are fixed +by means of iron rivets. On the under side of the bars there are +likewise plates fastened by rivets; each of the plates has small holes +the size of a finger, so that the lute will adhere when the interior is +lined. The dome has three iron rings engaged in wide holes in the heads +of iron claves, which fasten the bars to the middle band at these +points. Into these rings are fastened the hooks of the chains with which +the dome is raised, when the master is preparing the crucible. + +On the sole and the copper plates and the rock of the furnace, lute +mixed with straw is placed to a depth of three digits, and it is pounded +with a wooden rammer until it is compressed to a depth of one digit +only. The rammer-head is round and three palms high, two palms wide at +the bottom, and tapering upward; its handle is three feet long, and +where it is set into the rammer-head it is bound around with an iron +band. The top of the stonework in which the dome rests is also covered +with lute, likewise mixed with straw, to the thickness of a palm. All +this, as soon as it becomes loosened, must be repaired. + +[Illustration 470 (Cupellation Furnace): A--An artificer tamping the +crucible with a rammer. B--Large rammer. C--Broom. D--Two smaller +rammers. E--Curved iron plates. F--Part of a wooden strip. G--Sieve. +H--Ashes. I--Iron shovel. K--Iron plate. L--block of wood. M--Rock. +N--Basket made of woven twigs. O--Hooked bar. P--Second hooked bar. +Q--Old linen rag. R--bucket. S--Doeskin. T--Bundles of straw. V--Wood. +X--Cakes of lead alloy. Y--Fork. Z--Another workman covers the outside +of the furnace with lute where the dome fits on it. AA--Basket full of +ashes. BB--Lid of the dome. CC--The assistant standing on the steps +pours charcoal into the crucible through the hole at the top of the +dome. DD--Iron implement with which the lute is beaten. EE--Lute. +FF--Ladle with which the workman or master takes a sample. GG--Rabble +with which the scum of impure lead is drawn off. HH--Iron wedge with +which the silver mass is raised.] + +The artificer who undertakes the work of parting the metals, distributes +the operation into two shifts of two days. On the one morning he +sprinkles a little ash into the lute, and when he has poured some water +over it he brushes it over with a broom. Then he throws in sifted ashes +and dampens them with water, so that they could be moulded into balls +like snow. The ashes are those from which lye has been made by letting +water percolate through them, for other ashes which are fatty would have +to be burnt again in order to make them less fat. When he has made the +ashes smooth by pressing them with his hands, he makes the crucible +slope down toward the middle; then he tamps it, as I have described, +with a rammer. He afterward, with two small wooden rammers, one held in +each hand, forms the channel through which the litharge flows out. The +heads of these small rammers are each a palm wide, two digits thick, and +one foot high; the handle of each is somewhat rounded, is a digit and a +half less in diameter than the rammer-head, and is three feet in +length; the rammer-head as well as the handle is made of one piece of +wood. Then with shoes on, he descends into the crucible and stamps it in +every direction with his feet, in which manner it is packed and made +sloping. Then he again tamps it with a large rammer, and removing his +shoe from his right foot he draws a circle around the crucible with it, +and cuts out the circle thus drawn with an iron plate. This plate is +curved at both ends, is three palms long, as many digits wide, and has +wooden handles a palm and two digits long, and two digits thick; the +iron plate is curved back at the top and ends, which penetrate into +handles. There are some who use in the place of the plate a strip of +wood, like the rim of a sieve; this is three digits wide, and is cut out +at both ends that it may be held in the hands. Afterward he tamps the +channel through which the litharge discharges. Lest the ashes should +fall out, he blocks up the aperture with a stone shaped to fit it, +against which he places a board, and lest this fall, he props it with a +stick. Then he pours in a basketful of ashes and tamps them with the +large rammer; then again and again he pours in ashes and tamps them with +the rammer. When the channel has been made, he throws dry ashes all over +the crucible with a sieve, and smooths and rubs it with his hands. Then +he throws three basketsful of damp ashes on the margin all round the +edge of the crucible, and lets down the dome. Soon after, climbing upon +the crucible, he builds up ashes all around it, lest the molten alloy +should flow out. Then, having raised the lid of the dome, he throws a +basketful of charcoal into the crucible, together with an iron shovelful +of glowing coals, and he also throws some of the latter through the +apertures in the sides of the dome, and he spreads them with the same +shovel. This work and labour is finished in the space of two hours. + +An iron plate is set in the ground under the channel, and upon this is +placed a wooden block, three feet and a palm long, a foot and two palms +and as many digits wide at the back, and two palms and as many digits +wide in front; on the block of wood is placed a stone, and over it an +iron plate similar to the bottom one, and upon this he puts a basketful +of charcoal, and also an iron shovelful of burning charcoals. The +crucible is heated in an hour, and then, with the hooked bar with which +the litharge is drawn off, he stirs the remainder of the charcoal about. +This hook is a palm long and three digits wide, has the form of a double +triangle, and has an iron handle four feet long, into which is set a +wooden one six feet long. There are some who use instead a simple hooked +bar. After about an hour's time, he stirs the charcoal again with the +bar, and with the shovel throws into the crucible the burning charcoals +lying in the channel; then again, after the space of an hour, he stirs +the burning charcoals with the same bar. If he did not thus stir them +about, some blackness would remain in the crucible and that part would +be damaged, because it would not be sufficiently dried. Therefore the +assistant stirs and turns the burning charcoal that it may be entirely +burnt up, and so that the crucible may be well heated, which takes three +hours; then the crucible is left quiet for the remaining two hours. + +When the hour of eleven has struck, he sweeps up the charcoal ashes +with a broom and throws them out of the crucible. Then he climbs on to +the dome, and passing his hand in through its opening, and dipping an +old linen rag in a bucket of water mixed with ashes, he moistens the +whole of the crucible and sweeps it. In this way he uses two bucketsful +of the mixture, each holding five Roman _sextarii_,[28] and he does this +lest the crucible, when the metals are being parted, should break open; +after this he rubs the crucible with a doe skin, and fills in the +cracks. Then he places at the left side of the channel, two fragments of +hearth-lead, laid one on the top of the other, so that when partly +melted they remain fixed and form an obstacle, that the litharge will +not be blown about by the wind from the bellows, but remain in its +place. It is expedient, however, to use a brick in the place of the +hearth-lead, for as this gets much hotter, therefore it causes the +litharge to form more rapidly. The crucible in its middle part is made +two palms and as many digits deeper.[29] + +There are some who having thus prepared the crucible, smear it over with +incense[30], ground to powder and dissolved in white of egg, soaking it +up in a sponge and then squeezing it out again; there are others who +smear over it a liquid consisting of white of egg and double the amount +of bullock's blood or marrow. Some throw lime into the crucible through +a sieve. + +Afterward the master of the works weighs the lead with which the gold or +silver or both are mixed, and he sometimes puts a hundred +_centumpondia_[31] into the crucible, but frequently only sixty, or +fifty, or much less. After it has been weighed, he strews about in the +crucible three small bundles of straw, lest the lead by its weight +should break the surface. Then he places in the channel several cakes of +lead alloy, and through the aperture at the rear of the dome he places +some along the sides; then, ascending to the opening at the top of the +dome, he arranges in the crucible round about the dome the cakes which +his assistant hands to him, and after ascending again and passing his +hands through the same aperture, he likewise places other cakes inside +the crucible. On the second day those which remain he, with an iron +fork, places on the wood through the rear aperture of the dome. + +When the cakes have been thus arranged through the hole at the top of +the dome, he throws in charcoal with a basket woven of wooden twigs. +Then he places the lid over the dome, and the assistant covers over the +joints with lute. The master himself throws half a basketful of charcoal +into the crucible through the aperture next to the nozzle pipe, and +prepares the bellows, in order to be able to begin the second operation +on the morning of the following day. It takes the space of one hour to +carry out such a piece of work, and at twelve all is prepared. These +hours all reckoned up make a sum of eight hours. + +Now it is time that we should come to the second operation. In the +morning the workman takes up two shovelsful of live charcoals and throws +them into the crucible through the aperture next to the pipes of the +nozzles; then through the same hole he lays upon them small pieces of +fir-wood or of pitch pine, such as are generally used to cook fish. +After this the water-gates are opened, in order that the machine may be +turned which depresses the levers of the bellows. In the space of one +hour the lead alloy is melted; and when this has been done, he places +four sticks of wood, twelve feet long, through the hole in the back of +the dome, and as many through the channel; these sticks, lest they +should damage the crucible, are both weighted on the ends and supported +by trestles; these trestles are made of a beam, three feet long, two +palms and as many digits wide, two palms thick, and have two spreading +legs at each end. Against the trestle, in front of the channel, there is +placed an iron plate, lest the litharge, when it is extracted from the +furnace, should splash the smelter's shoes and injure his feet and legs. +With an iron shovel or a fork he places the remainder of the cakes +through the aperture at the back of the dome on to the sticks of wood +already mentioned. + +The native silver, or silver glance, or grey silver, or ruby silver, or +any other sort, when it has been flattened out[32], and cut up, and +heated in an iron crucible, is poured into the molten lead mixed with +silver, in order that impurities may be separated. As I have often said, +this molten lead mixed with silver is called _stannum_[33]. + +[Illustration 474 (Cupellation Furnace): A--Furnace. B--Sticks of wood. +C--Litharge. D--Plate. E--The foreman when hungry eats butter, that the +poison which the crucible exhales may not harm him, for this is a +special remedy against that poison.] + +When the long sticks of wood are burned up at the fore end, the master, +with a hammer, drives into them pointed iron bars, four feet long and +two digits wide at the front end, and beyond that one and a half digits +wide and thick; with these he pushes the sticks of wood forward and the +bars then rest on the trestles. There are others who, when they separate +metals, put two such sticks of wood into the crucible through the +aperture which is between the bellows, as many through the holes at the +back, and one through the channel; but in this case a larger number of +long sticks of wood is necessary, that is, sixty; in the former case, +forty long sticks of wood suffice to carry out the operation. When the +lead has been heated for two hours, it is stirred with a hooked bar, +that the heat may be increased. + +If it be difficult to separate the lead from the silver, he throws +copper and charcoal dust into the molten silver-lead alloy. If the alloy +of argentiferous gold and lead, or the silver-lead alloy, contains +impurities from the ore, then he throws in either equal portions of +argol and Venetian glass or of sal-ammoniac, or of Venetian glass and of +Venetian soap; or else unequal portions, that is, two of argol and one +of iron rust; there are some who mix a little saltpetre with each +compound. To one _centumpondium_ of the alloy is added a _bes_ or a +_libra_ and a third of the powder, according to whether it is more or +less impure. The powder certainly separates the impurities from the +alloy. Then, with a kind of rabble he draws out through the channel, +mixed with charcoal, the scum, as one might say, of the lead; the lead +makes this scum when it becomes hot, but that less of it may be made it +must be stirred frequently with the bar. + +Within the space of a quarter of an hour the crucible absorbs the lead; +at the time when it penetrates into the crucible it leaps and bubbles. +Then the master takes out a little lead with an iron ladle, which he +assays, in order to find what proportion of silver there is in the whole +of the alloy; the ladle is five digits wide, the iron part of its handle +is three feet long and the wooden part the same. Afterward, when they +are heated, he extracts with a bar the litharge which comes from the +lead and the copper, if there be any of it in the alloy. Wherefore, it +might more rightly be called _spuma_ of lead than of silver[34]. There +is no injury to the silver, when the lead and copper are separated from +it. In truth the lead becomes much purer in the crucible of the other +furnace, in which silver is refined. In ancient times, as the author +Pliny[35] relates, there was under the channel of the crucible another +crucible, and the litharge flowed down from the upper one into the lower +one, out of which it was lifted up and rolled round with a stick in +order that it might be of moderate weight. For which reason, they +formerly made it into small tubes or pipes, but now, since it is not +rolled round a stick, they make it into bars. + +If there be any danger that the alloy might flow out with the litharge, +the foreman keeps on hand a piece of lute, shaped like a cylinder and +pointed at both ends; fastening this to a hooked bar he opposes it to +the alloy so that it will not flow out. + +[Illustration 476 (Cleansing of Silver Cakes): A--Cake. B--Stone. +C--Hammer. D--Brass wire. E--Bucket containing water. F--Furnace from +which the cake has been taken, which is still smoking. G--Labourer +carrying a cake out of the works.] + +Now when the colour begins to show in the silver, bright spots appear, +some of them being almost white, and a moment afterward it becomes +absolutely white. Then the assistant lets down the water-gates, so that, +the race being closed, the water-wheel ceases to turn and the bellows +are still. Then the master pours several buckets of water on to the +silver to cool it; others pour beer over it to make it whiter, but this +is of no importance since the silver has yet to be refined. Afterward, +the cake of silver is raised with the pointed iron bar, which is three +feet long and two digits wide, and has a wooden handle four feet long +fixed in its socket. When the cake of silver has been taken from the +crucible, it is laid upon a stone, and from part of it the hearth-lead, +and from the other part the litharge, is chipped away with a hammer; +then it is cleansed with a bundle of brass wire dipped in water. When +the lead is separated from the silver, more silver is frequently found +than when it was assayed; for instance, if before there were three +_unciae_ and as many _drachmae_ in a _centumpondium_, they now sometimes +find three _unciae_ and a half[36]. Often the hearth-lead remaining in +the crucible is a palm deep; it is taken out with the rest of the ashes +and is sifted, and that which remains in the sieve, since it is +hearth-lead, is added to the hearth-lead[37]. + +The ashes which pass through the sieve are of the same use as they were +at first, for, indeed, from these and pulverised bones they make the +cupels. Finally, when much of it has accumulated, the yellow _pompholyx_ +adhering to the walls of the furnace, and likewise to those rings of the +dome near the apertures, is cleared away. + +[Illustration 479 (Crane for cupellation furnace): A--Crane-post. +B--Socket. C--Oak cross-sills. D--Band. E--Roof-beam. F--Frame. G--Lower +small cross-beam. H--Upright timber. I--Bars which come from the sides +of the crane-post. K--Bars which come from the sides of the upright +timber. L--Rundle drums. M--Toothed wheels. N--Chain. O--Pulley. +P--Beams of the crane-arm. Q--Oblique beams supporting the beams of the +crane-arm. R--Rectangular iron plates. S--Trolley. T--Dome of the +furnace. V--Ring. X--Three chains. Y--Crank. Z--The crane-post of the +other contrivance. AA--Crane-arm. BB--Oblique beam. CC--Ring of the +crane-arm. DD--The second ring. EE--Lever-bar. FF--Third ring. GG--Hook. +HH--Chain of the dome. II--Chain of the lever-bar.] + +I must also describe the crane with which the dome is raised. When it is +made, there is first set up a rectangular upright post twelve feet long, +each side of which measures a foot in width. Its lower pinion turns in a +bronze socket set in an oak sill; there are two sills placed crosswise +so that the one fits in a mortise in the middle of the other, and the +other likewise fits in the mortise of the first, thus making a kind of a +cross; these sills are three feet long and one foot wide and thick. The +crane-post is round at its upper end and is cut down to a depth of three +palms, and turns in a band fastened at each end to a roof-beam, from +which springs the inclined chimney wall. To the crane-post is affixed a +frame, which is made in this way: first, at a height of a cubit from the +bottom, is mortised into the crane-post a small cross-beam, a cubit and +three digits long, except its tenons, and two palms in width and +thickness. Then again, at a height of five feet above it, is another +small cross-beam of equal length, width, and thickness, mortised into +the crane-post. The other ends of these two small cross-beams are +mortised into an upright timber, six feet three palms long, and +three-quarters wide and thick; the mortise is transfixed by wooden pegs. +Above, at a height of three palms from the lower small cross-beam, are +two bars, one foot one palm long, not including the tenons, a palm three +digits wide, and a palm thick, which are mortised in the other sides of +the crane-post. In the same manner, under the upper small cross-beam are +two bars of the same size. Also in the upright timber there are mortised +the same number of bars, of the same length as the preceding, but three +digits thick, a palm two digits wide, the two lower ones being above the +lower small cross-beam. From the upright timber near the upper small +cross-beam, which at its other end is mortised into the crane-post, are +two mortised bars. On the outside of this frame, boards are fixed to the +small cross-beams, but the front and back parts of the frame have doors, +whose hinges are fastened to the boards which are fixed to the bars that +are mortised to the sides of the crane-post. + +Then boards are laid upon the lower small cross-beam, and at a height of +two palms above these there is a small square iron axle, the sides of +which are two digits wide; both ends of it are round and turn in bronze +or iron bearings, one of these bearings being fastened in the +crane-post, the other in the upright timber. About each end of the small +axle is a wooden disc, of three palms and a digit radius and one palm +thick, covered on the rim with an iron band; these two discs are distant +two palms and as many digits from each other, and are joined with five +rundles; these rundles are two and a half digits thick and are placed +three digits apart. Thus a drum is made, which is a palm and a digit +distant from the upright timber, but further from the crane-post, +namely, a palm and three digits. At a height of a foot and a palm above +this little axle is a second small square iron axle, the thickness of +which is three digits; this one, like the first one, turns in bronze or +iron bearings. Around it is a toothed wheel, composed of two discs a +foot three palms in diameter, a palm and two digits thick; on the rim of +this there are twenty-three teeth, a palm wide and two digits thick; +they protrude a palm from the wheel and are three digits apart. And +around this same axle, at a distance of two palms and as many digits +toward the upright timber, is another disc of the same diameter as the +wheel and a palm thick; this turns in a hollowed-out place in the +upright timber. Between this disc and the disc of the toothed wheel +another drum is made, having likewise five rundles. There is, in +addition to this second axle, at a height of a cubit above it, a small +wooden axle, the journals of which are of iron; the ends are bound round +with iron rings so that the journals may remain firmly fixed, and the +journals, like the little iron axles, turn in bronze or iron bearings. +This third axle is at a distance of about a cubit from the upper small +cross-beam; it has, near the upright timber, a toothed wheel two and a +half feet in diameter, on the rim of which are twenty-seven teeth; the +other part of this axle, near the crane-post, is covered with iron +plates, lest it should be worn away by the chain which winds around it. +The end link of the chain is fixed in an iron pin driven into the little +axle; this chain passes out of the frame and turns over a little pulley +set between the beams of the crane-arm. + +Above the frame, at a height of a foot and a palm, is the crane-arm. +This consists of two beams fifteen feet long, three palms wide, and two +thick, mortised into the crane-post, and they protrude a cubit from the +back of the crane-post and are fastened together. Moreover, they are +fastened by means of a wooden pin which penetrates through them and the +crane-post; this pin has at the one end a broad head, and at the other a +hole, through which is driven an iron bolt, so that the beams may be +tightly bound into the crane-post. The beams of the crane-arm are +supported and stayed by means of two oblique beams, six feet and two +palms long, and likewise two palms wide and thick; these are mortised +into the crane-post at their lower ends, and their upper ends are +mortised into the beams of the crane-arm at a point about four feet from +the crane-post, and they are fastened with iron nails. At the back of +the upper end of these oblique beams, toward the crane-post, is an iron +staple, fastened into the lower sides of the beams of the crane-arm, in +order that it may hold them fast and bind them. The outer end of each +beam of the crane-arm is set in a rectangular iron plate, and between +these are three rectangular iron plates, fixed in such a manner that the +beams of the crane-arm can neither move away from, nor toward, each +other. The upper sides of these crane-arm beams are covered with iron +plates for a length of six feet, so that a trolley can move on it. + +The body of the trolley is made of wood from the Ostrya or any other +hard tree, and is a cubit long, a foot wide, and three palms thick; on +both edges of it the lower side is cut out to a height and width of a +palm, so that the remainder may move backward and forward between the +two beams of the crane-arm; at the front, in the middle part, it is cut +out to a width of two palms and as many digits, that a bronze pulley, +around a small iron axle, may turn in it. Near the corners of the +trolley are four holes, in which as many small wheels travel on the +beams of the crane-arm. Since this trolley, when it travels backward and +forward, gives out a sound somewhat similar to the barking of a dog, we +have given it this name[38]. It is propelled forward by means of a +crank, and is drawn back by means of a chain. There is an iron hook +whose ring turns round an iron pin fastened to the right side of the +trolley, which hook is held by a sort of clavis, which is fixed in the +right beam of the crane-arm. + +At the end of the crane-post is a bronze pulley, the iron axle of which +is fastened in the beams of the crane-arm, and over which the chain +passes as it comes from the frame, and then, penetrating through the +hollow in the top of the trolley, it reaches to the little bronze pulley +of the trolley, and passing over this it hangs down. A hook on its end +engages a ring, in which are fixed the top links of three chains, each +six feet long, which pass through the three iron rings fastened in the +holes of the claves which are fixed into the middle iron band of the +dome, of which I have spoken. + +Therefore when the master wishes to lift the dome by means of the crane, +the assistant fits over the lower small iron axle an iron crank, which +projects from the upright beam a palm and two digits; the end of the +little axle is rectangular, and one and a half digits wide and one digit +thick; it is set into a similar rectangular hole in the crank, which is +two digits long and a little more than a digit wide. The crank is +semi-circular, and one foot three palms and two digits long, as many +digits wide, and one digit thick. Its handle is straight and round, and +three palms long, and one and a half digits thick. There is a hole in +the end of the little axle, through which an iron pin is driven so that +the crank may not come off. The crane having four drums, two of which +are rundle-drums and two toothed-wheels, is more easily moved than +another having two drums, one of which has rundles and the other teeth. + +Many, however, use only a simple contrivance, the pivots of whose +crane-post turn in the same manner, the one in an iron socket, the other +in a ring. There is a crane-arm on the crane-post, which is supported by +an oblique beam; to the head of the crane-arm a strong iron ring is +fixed, which engages a second iron ring. In this iron ring a strong +wooden lever-bar is fastened firmly, the head of which is bound by a +third iron ring, from which hangs an iron hook, which engages the rings +at the ends of the chains from the dome. At the other end of the +lever-bar is another chain, which, when it is pulled down, raises the +opposite end of the bar and thus the dome; and when it is relaxed the +dome is lowered. + +[Illustration 481 (Cupellation Furnace at Freiberg): A--Chamber of the +furnace. B--Its bed. C--Passages. D--Rammer. E--Mallet. F--Artificer +making tubes from litharge according to the Roman method. G--Channel. +H--Litharge. I--Lower crucible or hearth. K--Stick. L--Tubes.] + +In certain places, as at Freiberg in Meissen, the upper part of the +cupellation furnace is vaulted almost like an oven. This chamber is four +feet high and has either two or three apertures, of which the first, in +front, is one and a half feet high and a foot wide, and out of this +flows the litharge; the second aperture and likewise the third, if there +be three, are at the sides, and are a foot and a half high and two and a +half feet wide, in order that he who prepares the crucible may be able +to creep into the furnace. Its circular bed is made of cement, it has +two passages two feet high and one foot wide, for letting out the +vapour, and these lead directly through from one side to the other, so +that the one passage crosses the other at right angles, and thus four +openings are to be seen; these are covered at the top by rocks, wide, +but only a palm thick. On these and on the other parts of the interior +of the bed made of cement, is placed lute mixed with straw, to a depth +of three digits, as it was placed over the sole and the plates of copper +and the rocks of that other furnace. This, together with the ashes which +are thrown in, the master or the assistant, who, upon his knees, +prepares the crucible, tamps down with short wooden rammers and with +mallets likewise made of wood. + +[Illustration 482 (Cupellation Furnace in Poland): A--Furnace similar to +an oven. B--Passage. C--Iron bars. D--Hole through which the litharge is +drawn out. E--Crucible which lacks a dome. F--Thick sticks. G--Bellows.] + +The cupellation furnace in Poland and Hungary is likewise vaulted at +the top, and is almost similar to an oven, but in the lower part the bed +is solid, and there is no opening for the vapours, while on one side of +the crucible is a wall, between which and the bed of the crucible is a +passage in place of the opening for vapours; this passage is covered by +iron bars or rods extending from the wall to the crucible, and placed a +distance of two digits from each other. In the crucible, when it is +prepared, they first scatter straw, and then they lay in it cakes of +silver-lead alloy, and on the iron bars they lay wood, which when +kindled heats the crucible. They melt cakes to the weight of sometimes +eighty _centumpondia_ and sometimes a hundred _centumpondia_[39]. They +stimulate a mild fire by means of a blast from the bellows, and throw on +to the bars as much wood as is required to make a flame which will reach +into the crucible, and separate the lead from the silver. The litharge +is drawn out on the other side through an aperture that is just wide +enough for the master to creep through into the crucible. The Moravians +and Carni, who very rarely make more than a _bes_ or five-sixths of a +_libra_ of silver, separate the lead from it, neither in a furnace +resembling an oven, nor in the crucible covered by a dome, but on a +crucible which is without a cover and exposed to the wind; on this +crucible they lay cakes of silver-lead alloy, and over them they place +dry wood, and over these again thick green wood. The wood having been +kindled, they stimulate the fire by means of a bellows. + +[Illustration 484 (Refining Silver): A--Pestle with teeth. B--Pestle +without teeth. C--Dish or tray full of ashes. D--Prepared tests placed +on boards or shelves. E--Empty tests. F--Wood. G--Saw.] + +[Illustration 485 (Refining Silver): A--Straight knife having wooden +handles. B--Curved knife likewise having wooden handles. C--Curved knife +without wooden handles. D--Sieve. E--Balls. F--Iron door which the +master lets down when he refines silver, lest the heat of the fire +should injure his eyes. G--Iron implement on which the wood is placed +when the liquid silver is to be refined. H--Its other part passing +through the ring of another iron implement enclosed in the wall of the +furnace. I--Tests in which burning charcoal has been thrown.] + +I have explained the method of separating lead from gold or silver. Now +I will speak of the method of refining silver, for I have already +explained the process for refining gold. Silver is refined in a refining +furnace, over whose hearth is an arched chamber built of bricks; this +chamber in the front part is three feet high. The hearth itself is five +feet long and four wide. The walls are unbroken along the sides and +back, but in front one chamber is placed over the other, and above these +and the wall is the upright chimney. The hearth has a round pit, a cubit +wide and two palms deep, into which are thrown sifted ashes, and in this +is placed a prepared earthenware "test," in such a manner that it is +surrounded on all sides by ashes to a height equal to its own. The +earthenware test is filled with a powder consisting of equal portions of +bones ground to powder, and of ashes taken from the crucible in which +lead is separated from gold or silver; others mix crushed brick with the +ashes, for by this method the powder attracts no silver to itself. When +the powder has been made up and moistened with water, a little is thrown +into the earthenware test and tamped with a wooden pestle. This pestle +is round, a foot long, and a palm and a digit wide, out of which extend +six teeth, each a digit thick, and a digit and a third long and wide, +and almost a digit apart; these six teeth form a circle, and in the +centre of them is the seventh tooth, which is round and of the same +length as the others, but a digit and a half thick; this pestle tapers a +little from the bottom up, that the upper part of the handle may be +round and three digits thick. Some use a round pestle without teeth. +Then a little powder is again moistened, and thrown into the test, and +tamped; this work is repeated until the test is entirely full of the +powder, which the master then cuts out with a knife, sharp on both +sides, and turned upward at both ends so that the central part is a palm +and a digit long; therefore it is partly straight and partly curved. The +blade is one and a half digits wide, and at each end it turns upward two +palms, which ends to the depth of a palm are either not sharpened or +they are enclosed in wooden handles. The master holds the knife with one +hand and cuts out the powder from the test, so that it is left three +digits thick all round; then he sifts the powder of dried bones over it +through a sieve, the bottom of which is made of closely-woven bristles. +Afterward a ball made of very hard wood, six digits in diameter, is +placed in the test and rolled about with both hands, in order to make +the inside even and smooth; for that matter he may move the ball about +with only one hand. The tests[40] are of various capacities, for some of +them when prepared hold much less than fifteen _librae_ of silver, +others twenty, some thirty, others forty, and others fifty. All these +tests thus prepared are dried in the sun, or set in a warm and covered +place; the more dry and old they are the better. All of them, when used +for refining silver, are heated by means of burning charcoal placed in +them. Others use instead of these tests an iron ring; but the test is +more useful, for if the powder deteriorates the silver remains in it, +while there being no bottom to the ring, it falls out; besides, it is +easier to place in the hearth the test than the iron ring, and +furthermore it requires much less powder. In order that the test should +not break and damage the silver, some bind it round with an iron band. + +[Illustration 486 (Refining Silver): A--Grate. B--Brass block. C--Block +of wood. D--Cakes of silver. E--Hammer. F--Block of wood channelled in +the middle. G--Bowl full of holes. H--Block of wood fastened to an iron +implement. I--Fir-wood. K--Iron bar. L--Implement with a hollow end. The +implement which has a circular end is shown in the next picture. +M--Implement, the extremity of which is bent upwards. N--Implement in +the shape of tongs.] + +In order that they may be more easily broken, the silver cakes are +placed upon an iron grate by the refiner, and are heated by burning +charcoal placed under them. He has a brass block two palms and two +digits long and wide, with a channel in the middle, which he places upon +a block of hard wood. Then with a double-headed hammer, he beats the hot +cakes of silver placed on the brass block, and breaks them in pieces. +The head of this hammer is a foot and two digits long, and a palm wide. +Others use for this purpose merely a block of wood channelled in the +top. While the fragments of the cake are still hot, he seizes them with +the tongs and throws them into a bowl with holes in the bottom, and +pours water over them. When the fragments are cooled, he puts them +nicely into the test by placing them so that they stand upright and +project from the test to a height of two palms, and lest one should fall +against the other, he places little pieces of charcoal between them; +then he places live charcoal in the test, and soon two twig basketsful +of charcoal. Then he blows in air with the bellows. This bellows is +double, and four feet two palms long, and two feet and as many palms +wide at the back; the other parts are similar to those described in Book +VII. The nozzle of the bellows is placed in a bronze pipe a foot long, +the aperture in this pipe being a digit in diameter in front and quite +round, and at the back two palms wide. The master, because he needs for +the operation of refining silver a fierce fire, and requires on that +account a vigorous blast, places the bellows very much inclined, in +order that, when the silver has melted, it may blow into the centre of +the test. When the silver bubbles, he presses the nozzle down by means +of a small block of wood moistened with water and fastened to an iron +rod, the outer end of which bends upward. The silver melts when it has +been heated in the test for about an hour; when it is melted, he removes +the live coals from the test and places over it two billets of fir-wood, +a foot and three palms long, a palm two digits wide, one palm thick at +the upper part, and three digits at the lower. He joins them together at +the lower edges, and into the billets he again throws the coals, for a +fierce fire is always necessary in refining silver. It is refined in two +or three hours, according to whether it was pure or impure, and if it is +impure it is made purer by dropping granulated copper or lead into the +test at the same time. In order that the refiner may sustain the great +heat from the fire while the silver is being refined, he lets down an +iron door, which is three feet long and a foot and three palms high; +this door is held on both ends in iron plates, and when the operation is +concluded, he raises it again with an iron shovel, so that its edge +holds against the iron hook in the arch, and thus the door is held open. +When the silver is nearly refined, which may be judged by the space of +time, he dips into it an iron bar, three and a half feet long and a +digit thick, having a round steel point. The small drops of silver that +adhere to the bar he places on the brass block and flattens with a +hammer, and from their colour he decides whether the silver is +sufficiently refined or not. If it is thoroughly purified it is very +white, and in a _bes_ there is only a _drachma_ of impurities. Some +ladle up the silver with a hollow iron implement. Of each _bes_ of +silver one _sicilicus_ is consumed, or occasionally when very impure, +three _drachmae_ or half an _uncia_[41]. + +[Illustration 488 (Cleansing of Silver Cakes): A--Implement with a ring. +B--Ladle. C--Its hole. D--Pointed bar. E--Forks. F--Cake of silver laid +upon the implement shaped like tongs. G--Tub of water. H--Block of wood, +with a cake laid upon it. I--Hammer. K--Silver again placed upon the +implement resembling tongs. L--Another tub full of water. M--Brass +wires. N--Tripod. O--Another block. P--Chisel. Q--Crucible of the +furnace. R--Test still smoking.] + +The refiner governs the fire and stirs the molten silver with an iron +implement, nine feet long, a digit thick, and at the end first curved +toward the right, then curved back in order to form a circle, the +interior of which is a palm in diameter; others use an iron implement, +the end of which is bent directly upward. Another iron implement has the +shape of tongs, with which, by compressing it with his hands, he seizes +the coals and puts them on or takes them off; this is two feet long, one +and a half digits wide, and the third of a digit thick. + +When the silver is seen to be thoroughly refined, the artificer removes +the coals from the test with a shovel. Soon afterward he draws water in +a copper ladle, which has a wooden handle four feet long; it has a small +hole at a point half-way between the middle of the bowl and the edge, +through which a hemp seed just passes. He fills this ladle three times +with water, and three times it all flows out through the hole on to the +silver, and slowly quenches it; if he suddenly poured much water on it, +it would burst asunder and injure those standing near. The artificer has +a pointed iron bar, three feet long, which has a wooden handle as many +feet long, and he puts the end of this bar into the test in order to +stir it. He also stirs it with a hooked iron bar, of which the hook is +two digits wide and a palm deep, and the iron part of its handle is +three feet long and the wooden part the same. Then he removes the test +from the hearth with a shovel or a fork, and turns it over, and by this +means the silver falls to the ground in the shape of half a sphere; then +lifting the cake with a shovel he throws it into a tub of water, where +it gives out a great sound. Or else, having lifted the cake of silver +with a fork, he lays it upon the iron implement similar to tongs, which +are placed across a tub full of water; afterward, when cooled, he takes +it from the tub again and lays it on the block made of hard wood and +beats it with a hammer, in order to break off any of the powder from the +test which adheres to it. The cake is then placed on the implement +similar to tongs, laid over the tub full of water, and cleaned with a +bundle of brass wire dipped into the water; this operation of beating +and cleansing is repeated until it is all clean. Afterward he places it +on an iron grate or tripod; the tripod is a palm and two digits high, +one and a half digits wide, and its span is two palms wide; then he puts +burning charcoal under the tripod or grate, in order again to dry the +silver that was moistened by the water. Finally, the Royal Inspector[42] +in the employment of the King or Prince, or the owner, lays the silver +on a block of wood, and with an engraver's chisel he cuts out two small +pieces, one from the under and the other from the upper side. These are +tested by fire, in order to ascertain whether the silver is thoroughly +refined or not, and at what price it should be sold to the merchants. +Finally he impresses upon it the seal of the King or the Prince or the +owner, and, near the same, the amount of the weight. + +[Illustration 489 (Refining Silver): A--Muffle. B--Its little windows. +C--Its little bridge. D--Bricks. E--Iron door. F--Its little window. +G--Bellows. H--Hammer-chisel. I--Iron ring which some use instead of the +test. K--Pestle with which the ashes placed in the ring are pounded.] + +There are some who refine silver in tests placed under iron or +earthenware muffles. They use a furnace, on the hearth of which they +place the test containing the fragments of silver, and they place the +muffle over it; the muffle has small windows at the sides, and in front +a little bridge. In order to melt the silver, at the sides of the muffle +are laid bricks, upon which the charcoal is placed, and burning +firebrands are put on the bridge. The furnace has an iron door, which is +covered on the side next to the fire with lute in order that it may not +be injured. When the door is closed it retains the heat of the fire, but +it has a small window, so that the artificers may look into the test and +may at times stimulate the fire with the bellows. Although by this +method silver is refined more slowly than by the other, nevertheless it +is more useful, because less loss is caused, for a gentle fire consumes +fewer particles than a fierce fire continually excited by the blast of +the bellows. If, on account of its great size, the cake of silver can be +carried only with difficulty when it is taken out of the muffle, they +cut it up into two or three pieces while it is still hot, with a wedge +or a hammer-chisel; for if they cut it up after it has cooled, little +pieces of it frequently fly off and are lost. + + END OF BOOK X. + + +FOOTNOTES: + +[1] _Vile a precioso_. + +[2] The reagents mentioned in this Book are much the same as those of +Book VII, where (p. 220) a table is given showing the Latin and Old +German terms. Footnotes in explanation of our views as to these +substances may be most easily consulted through the index. + +[3] _Aqua valens_, literally strong, potent, or powerful water. It will +appear later, from the method of manufacture, that hydrochloric, nitric, +and sulphuric acids and _aqua regia_ were more or less all produced and +all included in this term. We have, therefore, used either the term +_aqua valens_ or simply _aqua_ as it occurs in the text. The terms _aqua +fortis_ and _aqua regia_ had come into use prior to Agricola, but he +does not use them; the Alchemists used various terms, often _aqua +dissolvia_. It is apparent from the uses to which this reagent was put +in separating gold and silver, from the method of clarifying it with +silver and from the red fumes, that Agricola could have had practical +contact only with nitric acid. It is probable that he has copied part of +the recipes for the compounds to be distilled from the Alchemists and +from such works as the _Probierbüchlein_. In any event he could not have +had experience with them all, for in some cases the necessary +ingredients for making nitric acid are not all present, and therefore +could be of no use for gold and silver separation. The essential +ingredients for the production of this acid by distillation, were +saltpetre, water, and either vitriol or alum. The other substances +mentioned were unnecessary, and any speculation as to the combinations +which would result, forms a useful exercise in chemistry, but of little +purpose here. The first recipe would no doubt produce hydrochloric acid. + +[4] Agricola, in the _Interpretatio_, gives the German equivalent for +the Latin _aerugo_ as _Spanschgrün_--"because it was first brought to +Germany from Spain; foreigners call it _viride aeris_ (copper green)." +The English "verdigris" is a corruption of _vert de grice_. Both +verdigris and white lead were very ancient products, and they naturally +find mention together among the ancient authors. The earliest +description of the method of making is from the 3rd Century B.C., by +Theophrastus, who says (101-2): "But these are works of art, as is also +Ceruse (_psimythion_) to make which, lead is placed in earthen vessels +over sharp vinegar, and after it has acquired some thickness of a kind +of rust, which it commonly does in about ten days, they open the vessels +and scrape off, as it were, a kind of foulness; they then place the lead +over the vinegar again, repeating over and over again the same method of +scraping it till it is wholly dissolved; what has been scraped off they +then beat to powder and boil for a long time; and what at last subsides +to the bottom of the vessel is the white lead.... Also in a manner +somewhat resembling this, verdigris (_ios_) is made, for copper is +placed over lees of wine (grape refuse?), and the rust which it acquires +by this means is taken off for use. And it is by this means that the +rust which appears is produced." (Based on Hill's translation.) +Vitruvius (VII, 12), Dioscorides (V, 51), and Pliny (XXXIV, 26 and 54), +all describe the method of making somewhat more elaborately. + +[5] _Amiantus_ (_Interpretatio_ gives _federwis_, _pliant_, +_salamanderhar_). From Agricola's elaborate description in _De Natura +Fossilium_ (p. 252) there can be no doubt that he means asbestos. This +mineral was well-known to the Ancients, and is probably earliest +referred to (3rd Century B.C.) by Theophrastus in the following passage +(29): "There is also found in the mines of Scaptesylae a stone, in its +external appearance somewhat resembling wood, on which, if oil be +poured, it burns; but when the oil is burnt away, the burning of the +stone ceases, as if it were in itself not liable to such accidents." +There can be no doubt that Strabo (X, 1) describes the mineral: "At +Carystus there is found in the earth a stone, which is combed like wool, +and woven, so that napkins are made of this substance, which, when +soiled, are thrown into the fire and cleaned, as in the washing of +linen." It is also described by Dioscorides (V, 113) and Pliny (XIX, 4). +Asbestos cloth has been found in Pre-Augustinian Roman tombs. + +[6] This list of four recipes is even more obscure than the previous +list. If they were distilled, the first and second mixtures would not +produce nitric acid, although possibly some sulphuric would result. The +third might yield nitric, and the fourth _aqua regia_. In view of the +water, they were certainly not used as cements, and the first and second +are deficient in the vital ingredients. + +[7] _Distillation_, at least in crude form, is very old. Aristotle +(_Meteorologica_, IV.) states that sweet water can be made by +evaporating salt-water and condensing the steam. Dioscorides and Pliny +both describe the production of mercury by distillation (note 58, p. +432). The Alchemists of the Alexandrian School, from the 1st to the 6th +Centuries, mention forms of imperfect apparatus--an ample discussion of +which may be found in Kopp, _Beiträge zur Geschichte der Chemie_, +Braunschweig, 1869, p. 217. + +[8] It is desirable to note the contents of the residues in the retort, +for it is our belief that these are the materials to which the author +refers as "lees of the water which separates gold from silver," in many +places in Book VII. They would be strange mixtures of sodium, potassium, +aluminium sulphates, with silica, brickdust, asbestos, and various +proportions of undigested vitriol, salt, saltpetre, alum, iron oxides, +etc. Their effect must have been uncertain. Many old German metallurgies +also refer to the _Todenkopf der Scheidwasser_, among them the +_Probierbüchlein_ before Agricola, and after him Lazarus Ercker +(_Beschreibung Allerfürnemsten_, etc., Prague, 1574). See also note 16, +p. 234. + +[9] This use of silver could apply to one purpose only, that is, the +elimination of minor amounts of hydrochloric from the nitric acid, the +former originating no doubt from the use of salt among the ingredients. +The silver was thus converted into a chloride and precipitated. This use +of a small amount of silver to purify the nitric acid was made by +metallurgists down to fairly recent times. Biringuccio (IV, 2) and +Lazarus Ercker (p. 71) both recommend that the silver be dissolved first +in a small amount of acid, and the solution poured into the +newly-manufactured supply. They both recommend preserving this +precipitate and its cupellation after melting with lead--which Agricola +apparently overlooked. + +[10] In this description of parting by nitric acid, the author digresses +from his main theme on pages 444 and 445, to explain a method apparently +for small quantities where the silver was precipitated by copper, and to +describe another cryptic method of precipitation. These subjects are +referred to in notes 11 and 12 below. The method of parting set out here +falls into six stages: _a_--cupellation, _b_--granulation, _c_--solution +in acid, _d_--treatment of the gold residues, _e_--evaporation of the +solution, _f_--reduction of the silver nitrate. For nitric acid parting, +bullion must be free from impurities, which cupellation would ensure; if +copper were left in, it would have the effect he mentions if we +understand "the silver separated from the gold soon unites with it +again," to mean that the silver unites with the copper, for the copper +would go into solution and come down with the silver on evaporation. +Agricola does not specifically mention the necessity of an excess of +silver in this description, although he does so elsewhere, and states +that the ratio must be at least three parts silver to one part gold. The +first description of the solution of the silver is clear enough, but +that on p. 445 is somewhat difficult to follow, for the author states +that the bullion is placed in a retort with the acid, and that +distillation is carried on between each additional charge of acid. So +far as the arrangement of a receiver might relate to the saving of any +acid that came over accidentally in the boiling, it can be understood, +but to distill off much acid would soon result in the crystallization of +the silver nitrate, which would greatly impede the action of subsequent +acid additions, and finally the gold could not be separated from such +nitrate in the way described. The explanation may be (apart from +incidental evaporation when heating) that the acids used were very weak, +and that by the evaporation of a certain amount of water, not only was +the acid concentrated, but room was provided for the further charges. +The acid in the gold wash-water, mentioned in the following paragraph, +was apparently thus concentrated. The "glass" mentioned as being melted +with litharge, argols, nitre, etc., was no doubt the silver nitrate. The +precipitation of the silver from the solution as a chloride, by the use +of salt, so generally used during the 18th and 19th Centuries, was known +in Agricola's time, although he does not mention it. It is mentioned in +Geber and the _Probierbüchlein_. The clarity of the latter on the +subject is of some interest (p. 34a): "How to pulverise silver and again +make it into silver. Take the silver and dissolve it in water with the +_starckenwasser_, _aqua fort_, and when that is done, take the silver +water and pour it into warm salty water, and immediately the silver +settles to the bottom and becomes powder. Let it stand awhile until it +has well settled, then pour away the water from it and dry the +settlings, which will become a powder like ashes. Afterward one can +again make it into silver. Take the powder and put it on a _test_, and +add thereto the powder from the settlings from which the _aqua forte_ +has been made, and add lead. Then if there is a great deal, blow on it +until the lead has incorporated itself ... blow it until it _plickt_ +(_blickens_). Then you will have as much silver as before." + +[11] The silver is apparently precipitated by the copper of the bowl. It +would seem that this method was in considerable use for small amounts of +silver nitrate in the 16th Century. Lazarus Ercker gives elaborate +directions for this method (_Beschreibung Allerfürnemsten_, etc., +Prague, 1574, p. 77). + +[12] We confess to a lack of understanding of this operation with leaves +of lead and copper. + +[13] We do not understand this "appearance of black." If the nitrate +came into contact with organic matter it would, of course, turn black by +reduction of the silver, and sunlight would have the same effect. + +[14] This would be equal to from 62 to 94 parts of copper in 1,000. + +[15] As 144 _siliquae_ are 1 _uncia_, then 1/4 _siliqua_ in 8 _unciae_ +would equal one part silver in 4,608 parts gold, or about 999.8 fine. + +[16] The object of this treatment with sulphur and copper is to separate +a considerable portion of silver from low-grade bullion (_i.e._, silver +containing some gold), in preparation for final treatment of the richer +gold-silver alloy with nitric acid. Silver sulphide is created by adding +sulphur, and is drawn off in a silver-copper regulus. After the first +sentence, the author uses silver alone where he obviously means silver +"containing some gold," and further he speaks of the "gold lump" +(_massula_) where he likewise means a button containing a great deal of +silver. For clarity we introduced the term "regulus" for the Latin +_mistura_. The operation falls into six stages: _a_, granulation; _b_, +sulphurization of the granulated bullion; _c_, melting to form a +combination of the silver sulphide with copper into a regulus, an alloy +of gold and silver settling out; _d_, repetition of the treatment to +abstract further silver from the "lump;" _e_, refining the "lump" with +nitric acid; _f_, recovery of the silver from the regulus by addition of +lead, liquation and cupellation. + +The use of a "circle of fire" secures a low temperature that would +neither volatilize the sulphur nor melt the bullion. The amount of +sulphur given is equal to a ratio of 48 parts bullion and 9 parts +sulphur. We are not certain about the translation of the paragraph in +relation to the proportion of copper added to the granulated bullion; +because in giving definite quantities of copper to be added in the +contingencies of various original copper contents in the bullion, it +would be expected that they were intended to produce some positive ratio +of copper and silver. However, the ratio as we understand the text in +various cases works out to irregular amounts, _i.e._, 48 parts of silver +to 16, 12.6, 24, 20.5, 20.8, 17.8, or 18 parts of copper. In order to +obtain complete separation there should be sufficient sulphur to have +formed a sulphide of the copper as well as of the silver, or else some +of the copper and silver would come down metallic with the "lump". The +above ratio of copper added to the sulphurized silver, in the first +instance would give about 18 parts of copper and 9 parts of sulphur to +48 parts of silver. The copper would require 4.5 parts of sulphur to +convert it into sulphide, and the silver about 7 parts, or a total of +11.5 parts required against 9 parts furnished. It is plain, therefore, +that insufficient sulphur is given. Further, the litharge would probably +take up some sulphur and throw down metallic lead into the "lump". +However, it is necessary that there should be some free metallics to +collect the gold, and, therefore, the separation could not be complete +in one operation. In any event, on the above ratios the "gold lump" from +the first operation was pretty coppery, and contained some lead and +probably a good deal of silver, because the copper would tend to +desulphurize the latter. The "powder" of glass-galls, salt, and litharge +would render the mass more liquid and assist the "gold lump" to separate +out. + +The Roman silver _sesterce_, worth about 2-1/8 pence or 4.2 American +cents, was no doubt used by Agricola merely to indicate an infinitesimal +quantity. The test to be applied to the regulus by way of cupellation +and parting of a sample with nitric acid, requires no explanation. The +truth of the description as to determining whether the gold had settled +out, by using a chalked iron rod, can only be tested by actual +experiment. It is probable, however, that the sulphur in the regulus +would attack the iron and make it black. The re-melting of the regulus, +if some gold remains in it, with copper and "powder" without more +sulphur, would provide again free metallics to gather the remaining +gold, and by desulphurizing some silver this button would probably not +be very pure. + +From the necessity for some free metallics besides the gold in the first +treatment, it will be seen that a repetition of the sulphur addition and +re-melting is essential gradually to enrich the "lump". Why more copper +is added is not clear. In the second melting, the ratio is 48 parts of +the "gold lump", 12 parts of sulphur and 12 parts copper. In this case +the added copper would require about 3 parts sulphur, and if we consider +the deficiency of sulphur in the first operations pertained entirely to +the copper, then about 2.5 parts would be required to make good the +shortage, or in other words the second addition of sulphur is +sufficient. In the final parting of the "lump" it will be noticed that +the author states that the silver ratio must be arranged as three of +silver to one of gold. As to the recovery of the silver from the +regulus, he states that 66 _librae_ of silver give 132 _librae_ of +_regulus_. To this, 500 _librae_ of lead are added, and it is melted in +the "second" furnace, and the litharge and hearth-lead made are +re-melted in the "first" furnace, the cakes made being again treated in +the "third" furnace to separate the copper and lead. The "first" is +usually the blast furnace, the "second" furnace is the cupellation +furnace, and the "third" the liquation furnace. It is difficult to +understand this procedure. The charge sent to the cupellation furnace +would contain between 3% and 5% copper, and between 3% and 5% sulphur. +However, possibly the sulphur and copper could be largely abstracted in +the skimmings from the cupellation furnace, these being subsequently +liquated in the "third" furnace. It may be noted that two whole lines +from this paragraph are omitted in the editions of _De Re Metallica_ +after 1600. For historical note on sulphur separation see page 461. + +[17] There can be no doubt that in most instances Agricola's _stibium_ +is antimony sulphide, but it does not follow that it was the mineral +_stibnite_, nor have we considered it desirable to introduce the +precision of either of these modern terms, and have therefore retained +the Latin term where the sulphide is apparently intended. The use of +antimony sulphide to part silver from gold is based upon the greater +affinity of silver than antimony for sulphur. Thus the silver, as in the +last process, is converted into a sulphide, and is absorbed in the +regulus, while the metallic antimony alloys with the gold and settles to +the bottom of the pot. This process has several advantages over the +sulphurization with crude sulphur; antimony is a more convenient vehicle +of sulphur, for it saves the preliminary sulphurization with its +attendant difficulties of volatilization of the sulphur; it also saves +the granulation necessary in the former method; and the treatment of the +subsequent products is simpler. However, it is possible that the +sulphur-copper process was better adapted to bullion where the +proportion of gold was low, because the fineness of the bullion +mentioned in connection with the antimonial process was apparently much +higher than the previous process. For instance, a _bes_ of gold, +containing 5, 6, or 7 double _sextulae_ of silver would be .792, .750 or +.708 fine. The antimonial method would have an advantage over nitric +acid separation, in that high-grade bullion could be treated direct +without artificial decrease of fineness required by inquartation to +about .250 fine, with the consequent incidental losses of silver +involved. + +The process in this description falls into six operations: _a_, +sulphurization of the silver by melting with antimony sulphide; _b_, +separation of the gold "lump" (_massula_) by jogging; _c_, re-melting +the regulus (_mistura_) three or four times for recovery of further +"lumps"; _d_, re-melting of the "lump" four times, with further +additions of antimony sulphide; _e_, cupellation of the regulus to +recover the silver; _f_, cupellation of the antimony from the "lump" to +recover the gold. Percy seems to think it difficult to understand the +insistence upon the addition of copper. Biringuccio (IV, 6) states, +among other things, that copper makes the ingredients more liquid. The +later metallurgists, however, such as Ercker, Lohneys, and Schlüter, do +not mention this addition; they do mention the "swelling and frothing," +and recommend that the crucible should be only partly filled. As to the +copper, we suggest that it would desulphurize part of the antimony and +thus free some of that metal to collect the gold. If we assume bullion +of the medium fineness mentioned and containing no copper, then the +proportions in the first charge would be about 36 parts gold, 12 parts +silver, 41 parts sulphur, 103 parts antimony, and 9 parts copper. The +silver and copper would take up 4.25 parts of sulphur, and thus free +about 10.6 parts of antimony as metallics. It would thus appear that the +amount of metallics provided to assist the collection of the gold was +little enough, and that the copper in freeing 5.6 parts of the antimony +was useful. It appears to have been necessary to have a large excess of +antimony sulphide; for even with the great surplus in the first charge, +the reaction was only partial, as is indicated by the necessity for +repeated melting with further antimony. + +The later metallurgists all describe the separation of the metallic +antimony from the gold as being carried out by oxidation of the +antimony, induced by a jet of air into the crucible, this being +continued until the mass appears limpid and no cloud forms in the +surface in cooling. Agricola describes the separation of the silver from +the regulus by preliminary melting with argols, glass-gall, and some +lead, and subsequent cupellation of the lead-silver alloy. The statement +that unless this preliminary melting is done, the cupel will absorb +silver, might be consonant with an attempt at cupellation of sulphides, +and it is difficult to see that much desulphurizing could take place +with the above fluxes. In fact, in the later descriptions of the +process, iron is used in this melting, and we are under the impression +that Agricola had omitted this item for a desulphurizing reagent. At the +Dresden Mint, in the methods described by Percy (Metallurgy Silver and +Gold, p. 373) the gold lumps were tested for fineness, and from this the +amount of gold retained in the regulus was computed. It is not clear +from Agricola's account whether the test with nitric acid was applied to +the regulus or to the "lumps". For historical notes see p. 461. + +[18] As will be shown in the historical note, this process of separating +gold and silver is of great antiquity--in all probability the only +process known prior to the Middle Ages, and in any event, the first one +used. In general the process was performed by "cementing" the +disintegrated bullion with a paste and subjecting the mass to +long-continued heat at a temperature under the melting point of the +bullion. The cement (_compositio_) is of two different species; in the +first species saltpetre and vitriol and some aluminous or silicious +medium are the essential ingredients, and through them the silver is +converted into nitrate and absorbed by the mass; in the second species, +common salt and the same sort of medium are the essentials, and in this +case the silver is converted into a chloride. Agricola does not +distinguish between these two species, for, as shown by the text, his +ingredients are badly mixed. + +The process as here described falls into five operations: _a_, +granulation of the bullion or preparation of leaves; _b_, heating +alternate layers of cement and bullion in pots; _c_, washing the gold to +free it of cement; _d_, melting the gold with borax or soda; _e_, +treatment of the cement by way of melting with lead and cupellation to +recover the silver. Investigation by Boussingault (_Ann. De Chimie_, +1833, p. 253-6), D'Elhuyar (_Bergbaukunde_, Leipzig, 1790, Vol. II, p. +200), and Percy (Metallurgy of Silver and Gold, p. 395), of the action +of common salt upon silver under cementation conditions, fairly well +demonstrated the reactions involved in the use of this species of +cement. Certain factors are essential besides salt: _a_, the admission +of air, which is possible through the porous pots used; _b_, the +presence of some moisture to furnish hydrogen; _c_, the addition of +alumina or silica. The first would be provided by Agricola in the use of +new pots, the second possibly by use of wood fuel in a closed furnace, +the third by the inclusion of brickdust. The alumina or silica at high +temperatures decomposes the salt, setting free hydrochloric acid and +probably also free chlorine. The result of the addition of vitriol in +Agricola's ingredients is not discussed by those investigators, but +inasmuch as vitriol decomposes into sulphuric acid under high +temperatures, this acid would react upon the salt to free hydrochloric +acid, and thus assist to overcome deficiencies in the other factors. It +is possible also that sulphuric acid under such conditions would react +directly upon the silver to form silver sulphates, which would be +absorbed into the cement. As nitric acid is formed by vitriol and +saltpetre at high temperatures, the use of these two substances as a +cementing compound would produce nitric acid, which would at once attack +the silver to form silver nitrate, which would be absorbed into the +melted cement. In this case the brickdust probably acted merely as a +vehicle for the absorption, and to lower the melting point of the mass +and prevent fusion of the metal. While nitric acid will only part gold +and silver when the latter is in great excess, yet when applied as fumes +under cementation conditions it appears to react upon a minor ratio of +silver. While the reactions of the two above species of compounds can be +accounted for in a general way, the problem furnished by Agricola's +statements is by no means simple, for only two of his compounds are +simply salt cements, the others being salt and nitre mixtures. An +inspection of these compounds produces at once a sense of confusion. +Salt is present in every compound, saltpetre in all but two, vitriol in +all but three. Lewis (_Traité Singulier de Métallique_, Paris, 1743, II, +pp. 48-60), in discussing these processes, states that salt and +saltpetre must never be used together, as he asserts that in this case +_aqua regia_ would be formed and the gold dissolved. Agricola, however, +apparently found no such difficulty. As to the other ingredients, apart +from nitre, salt, vitriol, and brickdust, they can have been of no use. +Agricola himself points out that ingredients of "metallic origin" +corrupt the gold and that brickdust and common salt are sufficient. In a +description of this process in the _Probierbüchlein_ (p. 58), no nitre +is mentioned. This booklet does mention the recovery of the silver from +the cement by amalgamation with mercury--the earliest mention of silver +amalgamation. + +[19] While a substance which we now know to be natural zinc sulphate was +known to Agricola (see note 11, p. 572), it is hardly possible that it +is referred to here. If green vitriol be dehydrated and powdered, it is +white. + +[20] The processes involved by these "other" compounds are difficult to +understand, because of the lack of information given as to the method of +operation. It might be thought that these were five additional recipes +for cementing pastes, but an inspection of their internal composition +soon dissipates any such assumption, because, apart from the lack of +brickdust or some other similar necessary ingredient, they all contain +more or less sulphur. After describing a preliminary treatment of the +bullion by cupellation, the author says: "Then the silver is sprinkled +with two _unciae_ of that powdered compound and is stirred. Afterward it +is poured into another crucible ... and violently shaken. The rest is +performed according to the process I have already explained." As he has +already explained four or five parting processes, it is not very clear +to which one this refers. In fact, the whole of this discussion reads as +if he were reporting hearsay, for it lacks in every respect the infinite +detail of his usual descriptions. In any event, if the powder was +introduced into the molten bullion, the effect would be to form some +silver sulphides in a regulus of different composition depending upon +the varied ingredients of different compounds. The enriched bullion was +settled out in a "lump" and treated "as I have explained," which is not +clear. + +[21] HISTORICAL NOTE ON PARTING GOLD AND SILVER. Although the earlier +Classics contain innumerable references to refining gold and silver, +there is little that is tangible in them, upon which to hinge the +metallurgy of parting the precious metals. It appears to us, however, +that some ability to part the metals is implied in the use of the +touchstone, for we fail to see what use a knowledge of the ratio of gold +and silver in bullion could have been without the power to separate +them. The touchstone was known to the Greeks at least as early as the +5th Century B.C. (see note 37, p. 252), and a part of Theophrastus' +statement (LXXVIII.) on this subject bears repetition in this +connection: "The nature of the stone which tries gold is also very +wonderful, as it seems to have the same power as fire; which is also a +test of that metal.... The trial by fire is by the colour and the +quantity lost by it, but that of the stone is made only by rubbing," +etc. This trial by fire certainly implies a parting of the metals. It +has been argued from the common use of _electrum_--a gold-silver +alloy--by the Ancients, that they did not know how to part the two +metals or they would not have wasted gold in such a manner, but it seems +to us that the very fact that _electrum_ was a positive alloy (20% gold, +80% silver), and that it was deliberately made (Pliny XXXIII, 23) and +held of value for its supposed superior brilliancy to silver and the +belief that goblets made of it detected poison, is sufficient answer to +this. + +To arrive by a process of elimination, we may say that in the Middle +Ages, between 1100 and 1500 A.D., there were known four methods of +parting these metals: _a_, parting by solution in nitric acid; _b_, +sulphurization of the silver in finely-divided bullion by heating it +with sulphur, and the subsequent removal of the silver sulphide in a +regulus by melting with copper, iron, or lead; _c_, melting with an +excess of antimony sulphide, and the direct conversion of the silver to +sulphide and its removal in a regulus; _d_, cementation of the +finely-divided bullion with salt, and certain necessary collateral +re-agents, and the separation of the silver by absorption into the +cement as silver chloride. Inasmuch as it can be clearly established +that mineral acids were unknown to the Ancients, we can eliminate that +method. Further, we may say at once that there is not, so far as has yet +been found, even a remote statement that could be applied to the +sulphide processes. As to cementation with salt, however, we have some +data at about the beginning of the Christian Era. + +Before entering into a more detailed discussion of the history of +various processes, it may be useful, in a word, to fix in the mind of +the reader our view of the first authority on various processes, and his +period. + + (1) Separation by cementation with salt, Strabo (?) 63 B.C.-24 + A.D.; Pliny 23-79 A.D. + + (2) Separation by sulphur, Theophilus, 1150-1200 A.D. + + (3) Separation by nitric acid, Geber, prior to 14th Century. + + (4) Separation by antimony sulphide, Basil Valentine, end 14th + Century, or _Probierbüchlein_, beginning 15th Century. + + (5) Separation by antimony sulphide and copper, or sulphur and + copper, _Probierbüchlein_, beginning 15th Century. + + (6) Separation by cementation with saltpetre, Agricola, 1556. + + (7) Separation by sulphur and iron, Schlüter, 1738. + + (8) Separation by sulphuric acid, D'Arcet, 1802. + + (9) Separation by chloride gas, Thompson, 1833. + + (10) Separation electrolytically, latter part 19th Century. + +PARTING BY CEMENTATION. The following passage from Strabo is of prime +interest as the first definite statement on parting of any kind (III, 2, +8): "That when they have melted the gold and purified it by means of a +kind of aluminous earth, the residue left is _electrum_. This, which +contains a mixture of silver and gold, being again subjected to the +fire, the silver is separated and the gold left (pure); for this metal +is easily dissipated and fat, and on this account gold is most easily +molten by straw, the flame of which is soft, and bearing a similarity +(to the gold) causes it easily to dissolve, whereas coal, besides +wasting a great deal, melts it too much, by reason of its vehemence, and +carries it off (in vapour)." This statement has provoked the liveliest +discussion, not only on account of the metallurgical interest and +obscurity, but also because of differences of view as to its +translation; we have given that of Mr. H. C. Hamilton (London, 1903). A +review of this discussion will be found in Percy's Metallurgy of Gold +and Silver, p. 399. That it refers to cementation at all hangs by a +slender thread, but it seems more nearly this than anything else. + +Pliny (XXXIII, 25) is a little more ample: "(The gold) is heated with +double its weight of salt and thrice its weight of _misy_, and again +with two portions of salt and one of a stone which they call _schistos_. +The _virus_ is drawn out when these things are burnt together in an +earthen crucible, itself remaining pure and incorrupt, the remaining ash +being preserved in an earthen pot and mixed with water as a lotion for +_lichen_ (ring-worm) on the face." Percy (Metallurgy Silver and Gold, p. +398) rightly considers that this undoubtedly refers to the parting of +silver and gold by cementation with common salt. Especially as Pliny +further on states that with regard to _misy_, "In purifying gold they +mix it with this substance." There can be no doubt from the explanations +of Pliny and Dioscorides that _misy_ was an oxidized pyrite, mostly iron +sulphate. Assuming the latter case, then all of the necessary elements +of cementation, _i.e._, vitriol, salt, and an aluminous or silicious +element, are present. + +The first entirely satisfactory evidence on parting is to be found in +Theophilus (12th Century), and we quote the following from Hendrie's +translation (p. 245): "Of Heating the Gold. Take gold, of whatsoever +sort it may be, and beat it until thin leaves are made in breadth three +fingers, and as long as you can. Then cut out pieces that are equally +long and wide and join them together equally, and perforate through all +with a fine cutting iron. Afterwards take two earthen pots proved in the +fire, of such size that the gold can lie flat in them, and break a tile +very small, or clay of the furnace burned and red, weigh it, powdered, +into two equal parts, and add to it a third part salt for the same +weight; which things being slightly sprinkled with urine, are mixed +together so that they may not adhere together, but are scarcely wetted, +and put a little of it upon a pot about the breadth of the gold, then a +piece of the gold itself, and again the composition, and again the gold, +which in the digestion is thus always covered, that gold may not be in +contact with gold; and thus fill the pot to the top and cover it above +with another pot, which you carefully lute round with clay, mixed and +beaten, and you place it over the fire, that it may be dried. In the +meantime compose a furnace from stones and clay, two feet in height, and +a foot and a half in breadth, wide at the bottom, but narrow at the top, +where there is an opening in the middle, in which project three long and +hard stones, which may be able to sustain the flame for a long time, +upon which you place the pots with the gold, and cover them with other +tiles in abundance. Then supply fire and wood, and take care that a +copious fire is not wanting for the space of a day and night. In the +morning taking out the gold, again melt, beat and place it in the +furnace as before. Again also, after a day and night, take it away and +mixing a little copper with it, melt it as before, and replace it upon +the furnace. And when you have taken it away a third time, wash and dry +it carefully, and so weighing it, see how much is wanting, then fold it +up and keep it." + +The next mention is by Geber, of whose date and authenticity there is +great doubt, but, in any event, the work bearing his name is generally +considered to be prior to the 14th, although he has been placed as early +as the 8th Century. We quote from Russell's translation, pp. 17 and 224, +which we have checked with the Latin edition of 1542: "Sol, or gold, is +beaten into thin plates and with them and common salt very well prepared +lay upon lay in a vessel of calcination which set into the furnace and +calcine well for three days until the whole is subtily calcined. Then +take it out, grind well and wash it with vinegar, and dry it in the sun. +Afterwards grind it well with half its weight of cleansed +_sal-armoniac_; then set it to be dissolved until the whole be dissolved +into most clear water." Further on: "Now we will declare the way of +cementing. Seeing it is known to us that cement is very necessary in the +examen of perfection, we say it is compounded of inflammable things. Of +this kind are, all blackening, flying, penetrating, and burned things; +as is vitriol, _sal-armoniac_, _flos aeris_ (copper oxide scales) and +the ancient _fictile_ stone (earthen pots), and a very small quantity, +or nothing, of sulphur, and urine with like acute and penetrating +things. All these are impasted with urine and spread upon thin plates of +that body which you intend shall be examined by this way of probation. +Then the said plates must be laid upon a grate of iron included in an +earthen vessel, yet so as one touch not the other that the virtue of the +fire may have free and equal access to them. Thus the whole must be kept +in fire in a strong earthen vessel for the space of three days. But here +great caution is required that the plates may be kept but not melt." + +Albertus Magnus (1205-1280) _De Mineralibus et Rebus Metallicis_, Lib. +IV, describes the process as follows:--"But when gold is to be purified +an earthen vessel is made like a cucurbit or dish, and upon it is placed +a similar vessel; and they are luted together with the tenacious lute +called by alchemists the lute of wisdom. In the upper vessel there are +numerous holes by which vapour and smoke may escape; afterwards the gold +in the form of short thin leaves is arranged in the vessel, the leaves +being covered consecutively with a mixture obtained by mixing together +soot, salt, and brick dust; and the whole is strongly heated until the +gold becomes perfectly pure and the base substances with which it was +mixed are consumed." It will be noted that salt is the basis of all +these cement compounds. We may also add that those of Biringuccio and +all other writers prior to Agricola were of the same kind, our author +being the first to mention those with nitre. + +PARTING WITH NITRIC ACID. The first mention of nitric acid is in +connection with this purpose, and, therefore, the early history of this +reagent becomes the history of the process. Mineral acids of any kind +were unknown to the Greeks or Romans. The works of the Alchemists and +others from the 12th to the 15th Centuries, have been well searched by +chemical historians for indications of knowledge of the mineral acids, +and many of such suspected indications are of very doubtful order. In +any event, study of the Alchemists for the roots of chemistry is fraught +with the greatest difficulty, for not only is there the large ratio of +fraud which characterised their operations, but there is even the much +larger field of fraud which characterised the authorship and dates of +writing attributed to various members of the cult. The mention of +saltpetre by Roger Bacon (1214-94), and Albertus Magnus (1205-80), have +caused some strain to read a knowledge of mineral acids into their +works, but with doubtful result. Further, the Monk Theophilus +(1150-1200) is supposed to have mentioned products which would be +mineral acids, but by the most careful scrutiny of that work we have +found nothing to justify such an assertion, and it is of importance to +note that as Theophilus was a most accomplished gold and silver worker, +his failure to mention it is at least evidence that the process was not +generally known. The transcribed manuscripts and later editions of such +authors are often altered to bring them "up-to-date." The first mention +is in the work attributed to Geber, as stated above, of date prior to +the 14th Century. The following passage from his _De Inventione +Veritatis_ (Nuremberg edition, 1545, p. 182) is of interest:--"First +take one _libra_ of vitriol of Cyprus and one-half _libra_ of saltpetre +and one-quarter of alum of Jameni, extract the _aqua_ with the redness +of the alembic--for it is very solvative--and use as in the foregoing +chapters. This can be made acute if in it you dissolve a quarter of +sal-ammoniac, which dissolves gold, sulphur, and silver." Distilling +vitriol, saltpetre and alum would produce nitric acid. The addition of +sal-ammoniac would make _aqua regia_; Geber used this solvent +water--probably without being made "more acute"--to dissolve silver, and +he crystallized out silver nitrate. It would not be surprising to find +all the Alchemists subsequent to Geber mentioning acids. It will thus be +seen that even the approximate time at which the mineral-acids were +first made cannot be determined, but it was sometime previous to the +15th Century, probably not earlier than the 12th Century. Beckmann +(Hist. of Inventions II, p. 508) states that it appears to have been an +old tradition that acid for separating the precious metals was first +used at Venice by some Germans; that they chiefly separated the gold +from Spanish silver and by this means acquired great riches. Beckmann +considers that the first specific description of the process seems to be +in the work of William Budaeus (_De Asse_, 1516, III, p. 101), who +speaks of it as new at this time. He describes the operation of one, Le +Conte, at Paris, who also acquired a fortune through the method. +Beckmann and others have, however, entirely overlooked the early +_Probierbüchlein_. If our conclusions are correct that the first of +these began to appear at about 1510, then they give the first +description of inquartation. This book (see appendix) is made up of +recipes, like a cook-book, and four or five different recipes are given +for this purpose; of these we give one, which sufficiently indicates a +knowledge of the art (p. 39): "If you would part them do it this way: +Beat the silver which you suppose to contain gold, as thin as possible; +cut it in small pieces and place it in 'strong' water (_starkwasser_). +Put it on a mild fire till it becomes warm and throws up blisters or +bubbles. Then take it and pour off the water into a copper-bowl; let it +stand and cool. Then the silver settles itself round the copper bowl; +let the silver dry in the copper bowl, then pour the water off and melt +the silver in a crucible. Then take the gold also out of the glass +_kolken_ and melt it together." Biringuccio (1540, Book VI.) describes +the method, but with much less detail than Agricola. He made his acid +from alum and saltpetre and calls it _lacque forti_. + +PARTING WITH SULPHUR. This process first appears in Theophilus +(1150-1200), and in form is somewhat different from that mentioned by +Agricola. We quote from Hendrie's Translation, p. 317, "How gold is +separated from silver. When you have scraped the gold from silver, place +this scraping in a small cup in which gold or silver is accustomed to be +melted, and press a small linen cloth upon it, that nothing may by +chance be abstracted from it by the wind of the bellows, and placing it +before the furnace, melt it; and directly lay fragments of sulphur in +it, according to the quantity of the scraping, and carefully stir it +with a thin piece of charcoal until its fumes cease; and immediately +pour it into an iron mould. Then gently beat it upon the anvil lest by +chance some of that black may fly from it which the sulphur has burnt, +because it is itself silver. For the sulphur consumes nothing of the +gold, but the silver only, which it thus separates from the gold, and +which you will carefully keep. Again melt this gold in the same small +cup as before, and add sulphur. This being stirred and poured out, break +what has become black and keep it, and do thus until the gold appear +pure. Then gather together all that black, which you have carefully +kept, upon the cup made from the bone and ash, and add lead, and so burn +it that you may recover the silver. But if you wish to keep it for the +service of niello, before you burn it add to it copper and lead, +according to the measure mentioned above, and mix with sulphur." This +process appears in the _Probierbüchlein_ in many forms, different +recipes containing other ingredients besides sulphur, such as salt, +saltpetre, sal-ammoniac, and other things more or less effective. In +fact, a series of hybrid methods between absolute melting with sulphur +and cementation with salt, were in use, much like those mentioned by +Agricola on p. 458. + +PARTING WITH ANTIMONY SULPHIDE. The first mention of this process lies +either in Basil Valentine's "Triumphant Chariot of Antimony" or in the +first _Probierbüchlein_. The date to be assigned to the former is a +matter of great doubt. It was probably written about the end of the 15th +Century, but apparently published considerably later. The date of the +_Probierbüchlein_ we have referred to above. The statement in the +"Triumphal Chariot" is as follows (Waite's Translation, p. 117-118): +"The elixir prepared in this way has the same power of penetrating and +pervading the body with its purifying properties that antimony has of +penetrating and purifying gold.... This much, however, I have proved +beyond a possibility of doubt, that antimony not only purifies gold and +frees it from foreign matter, but it also ameliorates all other metals, +but it does the same for animal bodies." There are most specific +descriptions of this process in the other works attributed to Valentine, +but their authenticity is so very doubtful that we do not quote. The +_Probierbüchlein_ gives several recipes for this process, all to the +same metallurgical effect, of which we quote two: "How to separate +silver from gold. Take 1 part of golden silver, 1 part of _spiesglass_, +1 part copper, 1 part lead; melt them together in a crucible. When +melted pour into the crucible pounded sulphur and directly you have +poured it in cover it up with soft lime so that the fumes cannot escape, +and let it get cold and you will find your gold in a button. Put that +same in a pot and blow on it." "How to part gold and silver by melting +or fire. Take as much gold-silver as you please and granulate it; take 1 +_mark_ of these grains, 1 _mark_ of powder; put them together in a +crucible. Cover it with a small cover, put it in the fire, and let it +slowly heat; blow on it gently until it melts; stir it all well together +with a stick, pour it out into a mould, strike the mould gently with a +knife so that the button may settle better, let it cool, then turn the +mould over, strike off the button and twice as much _spiesglas_ as the +button weighs, put them in a crucible, blow on it till it melts, then +pour it again into a mould and break away the button as at first. If you +want the gold to be good always add to the button twice as much +_spiesglass_. It is usually good gold in three meltings. Afterward take +the button, place it on a cupel, blow on it till it melts. And if it +should happen that the gold is covered with a membrane, then add a very +little lead, then it shines (_plickt_) and becomes clearer." Biringuccio +(1540) also gives a fairly clear exposition of this method. All the old +refiners varied the process by using mixtures of salt, antimony +sulphide, and sulphur, in different proportions, with and without lead +or copper; the net effect was the same. Later than Agricola these +methods of parting bullion by converting the silver into a sulphide and +carrying it off in a regulus took other forms. For instance, Schlüter +(_Hütte-Werken_, Braunschweig, 1738) describes a method by which, after +the granulated bullion had been sulphurized by cementation with sulphur +in pots, it was melted with metallic iron. Lampadius (_Grundriss Einer +Allgemeinen Hüttenkunde_, Göttingen, 1827) describes a treatment of the +bullion, sulphurized as above, with litharge, thus creating a +lead-silver regulus and a lead-silver-gold bullion which had to be +repeatedly put through the same cycle. The principal object of these +processes was to reduce silver bullion running low in gold to a ratio +acceptable for nitric acid treatment. + +Before closing the note on the separation of gold and silver, we may add +that with regard to the three processes largely used to-day, the +separation by solution of the silver from the bullion by concentrated +sulphuric acid where silver sulphate is formed, was first described by +D'Arcet, Paris, in 1802; the separation by introducing chlorine gas into +the molten bullion and thus forming silver chlorides was first described +by Lewis Thompson in a communication to the Society of Arts, 1833, and +was first applied on a large scale by F. B. Miller at the Sydney Mint in +1867-70; we do not propose to enter into the discussion as to who is the +inventor of electrolytic separation. + +[22] There were three methods of gilding practised in the Middle +Ages--the first by hammering on gold leaf; the second by laying a thin +plate of gold on a thicker plate of silver, expanding both together, and +fabricating the articles out of the sheets thus prepared; and the third +by coating over the article with gold amalgam, and subsequently driving +off the mercury by heat. Copper and iron objects were silver-plated by +immersing them in molten silver after coating with sal-ammoniac or +borax. Tinning was done in the same way. + +[23] See note 12, p. 297, for complete discussion of amalgamation. + +[24] These nine methods of separating gold from copper are based +fundamentally upon the sulphur introduced in each case, whereby the +copper is converted into sulphides and separated off as a matte. The +various methods are much befogged by the introduction of extraneous +ingredients, some of which serve as fluxes, while others would provide +metallics in the shape of lead or antimony for collection of the gold, +but others would be of no effect, except to increase the matte or slag. +Inspection will show that the amount of sulphur introduced in many +instances is in so large ratio that unless a good deal of volatilization +took place there would be insufficient metallics to collect the gold, if +it happened to be in small quantities. In a general way the auriferous +button is gradually impoverished in copper until it is fit for +cupellation with lead, except in one case where the final stage is +accomplished by amalgamation. The lore of the old refiners was much +after the order of that of modern cooks--they treasured and handed down +various efficacious recipes, and of those given here most can be found +in identical terms in the _Probierbüchlein_, some editions of which, as +mentioned before, were possibly fifty years before _De Re Metallica_. +This knowledge, no doubt, accumulated over long experience; but, so far +as we are aware, there is no description of sulphurizing copper for this +purpose prior to the publication mentioned. + +[25] _Sal artificiosus_. The compound given under this name is of quite +different ingredients from the stock fluxes given in Book VII under the +same term. The method of preparation, no doubt, dehydrated this one; it +would, however, be quite effective for its purpose of sulphurizing the +copper. There is a compound given in the _Probierbüchlein_ identical +with this, and it was probably Agricola's source of information. + +[26] Throughout the book the cupellation furnace is styled the _secunda +fornax_ (Glossary, _Treibeherd_). Except in one or two cases, where +there is some doubt as to whether the author may not refer to the second +variety of blast furnace, we have used "cupellation furnace." Agricola's +description of the actual operation of the old German cupellation is +less detailed than that of such authors as Schlüter (_Hütte-Werken_, +Braunschweig, 1738) or Winkler (_Beschreibung der Freyberger Schmelz +Huttenprozesse_, Freyberg, 1837). The operation falls into four periods. +In the first period, or a short time after melting, the first scum--the +_abzug_--arises. This material contains most of the copper, iron, zinc, +or sulphur impurities in the lead. In the second period, at a higher +temperature, and with the blast turned on, a second scum arises--the +_abstrich_. This material contains most of the antimony and arsenical +impurities. In the third stage the litharge comes over. At the end of +this stage the silver brightens--"_blicken_"--due to insufficient +litharge to cover the entire surface. Winkler gives the following +average proportion of the various products from a charge of 100 +_centners_:-- + + _Abzug_ 2 _centners_, containing 64% lead + _Abstrich_ 5-1/2 " " 73% " + _Herdtplei_ 21-1/2 " " 60% " + Impure litharge 18 " " 85% " + Litharge 66 " " 89% " + --- + Total 113 _centners_ + +He estimates the lead loss at from 8% to 15%, and gives the average +silver contents of _blicksilber_ as about 90%. Many analyses of the +various products may be found in Percy (Metallurgy of Lead, pp. +198-201), Schnabel and Lewis (Metallurgy, Vol. I, p. 581); but as they +must vary with every charge, a repetition of them here is of little +purpose. + +HISTORICAL NOTE ON CUPELLATION. The cupellation process is of great +antiquity, and the separation of silver from lead in this manner very +probably antedates the separation of gold and silver. We can be certain +that the process has been used continuously for at least 2,300 years, +and was only supplanted in part by Pattinson's crystallization process +in 1833, and further invaded by Parks' zinc method in 1850, and during +the last fifteen years further supplanted in some works by electrolytic +methods. However, it yet survives as an important process. It seems to +us that there is no explanation possible of the recovery of the large +amounts of silver possessed from the earliest times, without assuming +reduction of that metal with lead, and this necessitates cupellation. If +this be the case, then cupellation was practised in 2500 B.C. The +subject has been further discussed on p. 389. The first direct evidence +of the process, however, is from the remains at Mt. Laurion (note 6, p. +27), where the period of greatest activity was at 500 B.C., and it was +probably in use long before that time. Of literary evidences, there are +the many metaphorical references to "fining silver" and "separating +dross" in the Bible, such as Job (XXVIII, 1), Psalms (XII, 6, LXVI, 10), +Proverbs (XVII, 3). The most certain, however, is Jeremiah (VI, 28-30): +"They are all brass [_sic_] and iron; they are corrupters. The bellows +are burned, the lead is consumed in the fire, the founder melteth in +vain; for the wicked are not plucked away. Reprobate silver shall men +call them." Jeremiah lived about 600 B.C. His contemporary Ezekiel +(XXII, 18) also makes remark: "All they are brass and tin and iron and +lead in the midst of the furnace; they are even the dross of the +silver." Among Greek authors Theognis (6th century B.C.) and Hippocrates +(5th century B.C.) are often cited as mentioning the refining of gold +with lead, but we do not believe their statements will stand this +construction without strain. Aristotle (Problems XXIV, 9) makes the +following remark, which has been construed not only as cupellation, but +also as the refining of silver in "tests." "What is the reason that +boiling water does not leap out of the vessel ... silver also does this +when it is purified. Hence those whose office it is in the silversmiths' +shops to purify silver, derive gain by appropriation to themselves of +the sweepings of silver which leap out of the melting-pot." + +The quotation of Diodorus Siculus from Agatharchides (2nd century B.C.) +on gold refining with lead and salt in Egypt we give in note 8, p. 279. +The methods quoted by Strabo (63 B.C.-24 A.D.) from Polybius (204-125 +B.C.) for treating silver, which appear to involve cupellation, are +given in note 8, p. 281. It is not, however, until the beginning of the +Christian era that we get definite literary information, especially with +regard to litharge, in Dioscorides and Pliny. The former describes many +substances under the terms _scoria_, _molybdaena_, _scoria argyros_ and +_lithargyros_, which are all varieties of litharge. Under the latter +term he says (V, 62): "One kind is produced from a lead sand +(concentrates?), which has been heated in the furnaces until completely +fused; another (is made) out of silver; another from lead. The best is +from Attica, the second (best) from Spain; after that the kinds made in +Puteoli, in Campania, and at Baia in Sicily, for in these places it is +mostly produced by burning lead plates. The best of all is that which is +a bright golden colour, called _chrysitis_, that from Sicily (is called) +_argyritis_, that made from silver is called _lauritis_." Pliny refers +in several passages to litharge (_spuma argenti_) and to what is +evidently cupellation, (XXXIII, 31): "And this the same agency of fire +separates part into lead, which floats on the silver like oil on water" +(XXXIV, 47). "The metal which flows liquid at the first melting is +called _stannum_, the second melting is silver; that which remains in +the furnace is _galena_, which is added to a third part of the ore. This +being again melted, produced lead with a deduction of two-ninths." +Assuming _stannum_ to be silver-lead alloy, and _galena_ to be +_molybdaena_, and therefore litharge, this becomes a fairly clear +statement of cupellation (see note 23, p. 392). He further states +(XXXIII, 35): "There is made in the same mines what is called _spuma +argenti_ (litharge). There are three varieties of it; the best, known as +_chrysitis_; the second best, which is called _argyritis_; and a third +kind, which is called _molybditis_. And generally all these colours are +to be found in the same tubes (see p. 480). The most approved kind is +that of Attica; the next, that which comes from Spain. _Chrysitis_ is +the product from the ore itself; _argyritis_ is made from the silver, +and _molybditis_ is the result of smelting of lead, which is done at +Puteoli, and from this has its name. All three are made as the material +when smelted flows from an upper crucible into a lower one. From this +last it is raised with an iron bar, and is then twirled round in the +flames in order to make it less heavy (made in tubes). Thus, as may be +easily perceived from the name, it is in reality the _spuma_ of a +boiling substance--of the future metal, in fact. It differs from slag in +the same way that the scum of a liquid differs from the lees, the one +being purged from the material while purifying itself, the other an +excretion of the metal when purified." + +The works of either Theophilus (1150-1200 A.D.) or Geber (prior to the +14th century) are the first where adequate description of the cupel +itself can be found. The uncertainty of dates renders it difficult to +say which is earliest. Theophilus (Hendrie's Trans., p. 317) says: "How +gold is separated from copper: But if at any time you have broken copper +or silver-gilt vessels, or any other work, you can in this manner +separate the gold. Take the bones of whatever animal you please, which +(bones) you may have found in the street, and burn them, being cold, +grind them finely, and mix with them a third part of beechwood ashes, +and make cups as we have mentioned above in the purification of silver; +you will dry these at the fire or in the sun. Then you carefully scrape +the gold from the copper, and you will fold this scraping in lead beaten +thin, and one of these cups being placed in the embers before the +furnace, and now become warm, you place in this fold of lead with the +scraping, and coals being heaped upon it you will blow it. And when it +has become melted, in the same manner as silver is accustomed to be +purified, sometimes by removing the embers and by adding lead, sometimes +by re-cooking and warily blowing, you burn it until, the copper being +entirely absorbed, the gold may appear pure." + +We quote Geber from the Nuremberg edition of 1545, p. 152: "Now we +describe the method of this. Take sifted ashes or _calx_, or the powder +of the burned bones of animals, or all of them mixed, or some of them; +moisten with water, and press it with your hand to make the mixture firm +and solid, and in the middle of this bed make a round solid crucible and +sprinkle a quantity of crushed glass. Then permit it to dry. When it is +dry, place into the crucible that which we have mentioned which you +intend to test. On it kindle a strong fire, and blow upon the surface of +the body that is being tested until it melts, which, when melted, piece +after piece of lead is thrown upon it, and blow over it a strong flame. +When you see it agitated and moved with strong shaking motion it is not +pure. Then wait until all of the lead is exhaled. If it vanishes and +does not cease its motion it is not purified. Then again throw lead and +blow again until the lead separates. If it does not become quiet again, +throw in lead and blow on it until it is quiet and you see it bright and +clear on the surface." + +Cupellation is mentioned by most of the alchemists, but as a +metallurgical operation on a large scale the first description is by +Biringuccio in 1540. + +[27] In Agricola's text this is "first,"--obviously an error. + +[28] The Roman _sextarius_ was about a pint. + +[29] This sentence continues, _Ipsa vero media pars praeterea digito_, +to which we are unable to attribute any meaning. + +[30] _Thus_, or _tus_--"incense." + +[31] One _centumpondium_, Roman, equals about 70.6 lbs. avoirdupois; one +_centner_, old German, equals about 114.2 lbs. avoirdupois. Therefore, +if German weights are meant, the maximum charge would be about 5.7 short +tons; if Roman weights, about 3.5 short tons. + +[32] See description, p. 269. + +[33] _Stannum_, as a term for lead-silver alloys, is a term which +Agricola (_De Natura Fossilium_, pp. 341-3) adopted from his views of +Pliny. In the _Interpretatio_ and the Glossary he gives the German +equivalent as _werk_, which would sufficiently identify his meaning were +it not obvious from the context. There can be little doubt that Pliny +uses the term for lead alloys, but it had come into general use for tin +before Agricola's time. The Roman term was _plumbum candidum_, and as a +result of Agricola's insistence on using it and _stannum_ in what he +conceived was their original sense, he managed to give considerable +confusion to mineralogic literature for a century or two. The passages +from Pliny, upon which he bases his use, are (XXXIV, 47): "The metal +which flows liquid at the first melting in the furnace is called +_stannum_, the second melting is silver," etc. (XXXIV, 48): "When copper +vessels are coated with _stannum_ they produce a less disagreeable +flavour, and it prevents verdigris. It is also remarkable that the +weight is not increased.... At the present day a counterfeit _stannum_ +is made by adding one-third of white copper to tin. It is also made in +another way, by mixing together equal parts of tin and lead; this last +is called by some _argentarium_.... There is also a composition called +_tertiarium_, a mixture of two parts of lead and one of tin. Its price +is twenty _denarii_ per pound, and it is used for soldering pipes. +Persons still more dishonest mix together equal parts of _tertiarium_ +and tin, and calling the compound _argentarium_, when it is melted coat +articles with it." Although this last passage probably indicates that +_stannum_ was a tin compound, yet it is not inconsistent with the view +that the genuine _stannum_ was silver-lead, and that the counterfeits +were made as stated by Pliny. At what period the term _stannum_ was +adopted for tin is uncertain. As shown by Beckmann (Hist. of Inventions +II, p. 225), it is used as early as the 6th century in occasions where +tin was undoubtedly meant. We may point out that this term appears +continuously in the official documents relating to Cornish tin mining, +beginning with the report of William de Wrotham in 1198. + +[34] The Latin term for litharge is _spuma argenti_, spume of silver. + +[35] Pliny, XXXIII, 35. This quotation is given in full in the footnote +p. 466. Agricola illustrates these "tubes" of litharge on p. 481. + +[36] Assuming Roman weights, three _unciae_ and three _drachmae_ per +_centumpondium_ would be about 82 ozs., and the second case would equal +about 85 ozs. per short ton. + +[37] Agricola uses throughout _De Re Metallica_ the term _molybdaena_ +for this substance. It is obvious from the context that he means +saturated furnace bottoms--the _herdpley_ of the old German +metallurgists--and, in fact, he himself gives this equivalent in the +_Interpretatio_, and describes it in great detail in _De Natura +Fossilium_ (p. 353). The derivatives coined one time and another from +the Greek _molybdos_ for lead, and their applications, have resulted in +a stream of wasted ink, to which we also must contribute. Agricola chose +the word _molybdaena_ in the sense here used from his interpretation of +Pliny. The statements in Pliny are a hopeless confusion of _molybdaena_ +and _galena_. He says (XXXIII, 35): "There are three varieties of it +(litharge)--the best-known is _chrysitis_; the second best is called +_argyritis_; and a third kind is called _molybditis_.... _Molybditis_ is +the result of the smelting of lead.... Some people make two kinds of +litharge, which they call _scirerytis_ and _peumene_; and a third +variety being _molybdaena_, will be mentioned with lead." (XXXIV, 53): +"_Molybdaena_, which in another place I have called _galena_, is an ore +of mixed silver and lead. It is considered better in quality the nearer +it approaches to a golden colour and the less lead there is in it; it is +also friable and moderately heavy. When it is boiled with oil it becomes +liver-coloured, adheres to the gold and silver furnaces, and in this +state it is called _metallica_." From these two passages it would seem +that _molybdaena_, a variety of litharge, might quite well be +hearth-lead. Further (in XXXIV, 47), he says: "The metal which flows +liquid at the first melting in the furnace is called _stannum_, at the +second melting is silver, that which remains in the furnace is +_galena_." If we still maintain that _molybdaena_ is hearth-lead, and +_galena_ is its equivalent, then this passage becomes clear enough, the +second melting being cupellation. The difficulty with Pliny, however, +arises from the passage (XXXIII, 31), where, speaking of silver ore, he +says: "It is impossible to melt it except with lead ore, called +_galena_, which is generally found next to silver veins." Agricola +(_Bermannus_, p. 427, &c.), devotes a great deal of inconclusive +discussion to an attempt to reconcile this conflict of Pliny, and also +that of Dioscorides. The probable explanation of this conflict arises in +the resemblance of cupellation furnace bottoms to lead carbonates, and +the native _molybdaena_ of Dioscorides; and some of those referred to by +Pliny may be this sort of lead ores. In fact, in one or two places in +Book IX, Agricola appears to use the term in this sense himself. After +Agricola's time the term _molybdaenum_ was applied to substances +resembling lead, such as graphite, and what we now know as _molybdenite_ +(_MoS_{2}_). Some time in the latter part of the 18th century, an +element being separated from the latter, it was dubbed _molybdenum_, and +confusion was five times confounded. + +[38] Agricola here refers to the German word used in this connection, +_i.e._, _hundt_, a dog. + +[39] If Agricola means the German _centner_, this charge would be from +about 4.6 to 5.7 short tons. If he is using Roman weights, it would be +from about 3 to 3.7 short tons. + +[40] The refining of silver in "tests" (Latin _testa_) is merely a +second cupellation, with greater care and under stronger blast. Stirring +the mass with an iron rod serves to raise the impurities which either +volatilize as litharge or, floating to the edges, are absorbed into the +"test." The capacity of the tests, from 15 _librae_ to 50 _librae_, +would be from about 155 to 515 ozs. Troy. + +[41] A _drachma_ of impurities in a _bes_, would be one part in 64, or +984.4 fine. A loss of a _sicilicus_ of silver to the _bes_, would be one +part in 32, or about 3.1%; three _drachmae_ would equal 4.7%, and half +an _uncia_ 6.2%, or would indicate that the original bullion had a +fineness in the various cases of about 950, 933, and 912. + +[42] _Praefectus Regis_. + + + + +BOOK XI. + + +Different methods of parting gold from silver, and, on the other hand, +silver from gold, were discussed in the last book; also the separation +of copper from the latter, and further, of lead from gold as well as +from silver; and, lastly, the methods for refining the two precious +metals. Now I will speak of the methods by which silver must be +separated from copper, and likewise from iron.[1] + +[Illustration 493 (Building Plan for Refinery): Six long walls: A--The +first. B--The first part of the second. C--The further part of the +second. D--The third. E--The fourth. F--The fifth. G--The sixth. +Fourteen transverse walls: H--The first. I--The second. K--The third. +L--The fourth. M--The fifth. N--The sixth. O--The seventh. P--The +eighth. Q--The ninth. R--The tenth. S--The eleventh. T--The twelfth. +V--The thirteenth. X--The fourteenth.] + +The _officina_, or the building necessary for the purposes and use of +those who separate silver from copper, is constructed in this manner. +First, four long walls are built, of which the first, which is parallel +with the bank of a stream, and the second, are both two hundred and +sixty-four feet long. The second, however, stops at one hundred and +fifty-one feet, and after, as it were, a break for a length of +twenty-four feet, it continues again until it is of a length equal to +the first wall. The third wall is one hundred and twenty feet long, +starting at a point opposite the sixty-seventh foot of the other walls, +and reaching to their one hundred and eighty-sixth foot. The fourth +wall is one hundred and fifty-one feet long. The height of each of these +walls, and likewise of the other two and of the transverse walls, of +which I will speak later on, is ten feet, and the thickness two feet and +as many palms. The second long wall only is built fifteen feet high, +because of the furnaces which must be built against it. The first long +wall is distant fifteen feet from the second, and the third is distant +the same number of feet from the fourth, but the second is distant +thirty-nine feet from the third. Then transverse walls are built, the +first of which leads from the beginning of the first long wall to the +beginning of the second long wall; and the second transverse wall from +the beginning of the second long wall to the beginning of the fourth +long wall, for the third long wall does not reach so far. Then from the +beginning of the third long wall are built two walls--the one to the +sixty-seventh foot of the second long wall, the other to the same point +in the fourth long wall. The fifth transverse wall is built at a +distance of ten feet from the fourth transverse wall toward the second +transverse wall; it is twenty feet long, and starts from the fourth +long wall. The sixth transverse wall is built also from the fourth long +wall, at a point distant thirty feet from the fourth transverse wall, +and it extends as far as the back of the third long wall. The seventh +transverse wall is constructed from the second long wall, where this +first leaves off, to the third long wall; and from the back of the third +long wall the eighth transverse wall is built, extending to the end of +the fourth long wall. Then the fifth long wall is built from the seventh +transverse wall, starting at a point nineteen feet from the second long +wall; it is one hundred and nine feet in length; and at a point +twenty-four feet along it, the ninth transverse wall is carried to the +third end of the second long wall, where that begins again. The tenth +transverse wall is built from the end of the fifth long wall, and leads +to the further end of the second long wall; and from there the eleventh +transverse wall leads to the further end of the first long wall. Behind +the fifth long wall, and five feet toward the third long wall, the sixth +long wall is built, leading from the seventh transverse wall; its length +is thirty-five feet, and from its further end the twelfth transverse +wall is built to the third long wall, and from it the thirteenth +transverse wall is built to the fifth long wall. The fourteenth +transverse wall divides into equal parts the space which lies between +the seventh transverse wall and the twelfth. + +The length, height, breadth, and position of the walls are as above. +Their archways, doors, and openings are made at the same time that the +walls are built. The size of these and the way they are made will be +much better understood hereafter. I will now speak of the furnace hoods +and of the roofs. The first side[2] of the hood stands on the second +long wall, and is similar in every respect to those whose structure I +explained in Book IX, when I described the works in whose furnaces are +smelted the ores of gold, silver, and copper. From this side of the hood +a roof, which consists of burnt tiles, extends to the first long wall; +and this part of the building contains the bellows, the machinery for +compressing them, and the instruments for inflating them. In the middle +space, which is situated between the second and third transverse walls, +an upright post eight feet high and two feet thick and wide, is erected +on a rock foundation, and is distant thirteen feet from the second long +wall. On that upright post, and in the second transverse wall, which has +at that point a square hole two feet high and wide, is placed a beam +thirty-four feet and a palm long. Another beam, of the same length, +width, and thickness, is fixed on the same upright post and in the third +transverse wall. The heads of those two beams, where they meet, are +joined together with iron staples. In a similar manner another post is +erected, at a distance of ten feet from the first upright post in the +direction of the fourth wall, and two beams are laid upon it and into +the same walls in a similar way to those I have just now described. On +these two beams and on the fourth long wall are fixed seventeen +cross-beams, forty-three feet and three palms long, a foot wide, and +three palms thick; the first of these is laid upon the second transverse +wall, the last lies along the third and fourth transverse walls; the +rest are set in the space between them. These cross-beams are three feet +apart one from the other. + +In the ends of these cross-beams, facing the second long wall, are +mortised the ends of the same number of rafters reaching to those +timbers which stand upright on the second long wall, and in this manner +is made the inclined side of the hood in a similar way to the one +described in Book IX. To prevent this from falling toward the vertical +wall of the hood, there are iron rods securing it, but only a few, +because the four brick chimneys which have to be built in that space +partly support it. Twelve feet back are likewise mortised into the +cross-beams, which lie upon the two longitudinal beams and the fourth +long wall, the lower ends of as many rafters, whose upper ends are +mortised into the upper ends of an equal number of similar rafters, +whose lower ends are mortised to the ends of the beams at the fourth +long wall. From the first set of rafters[4] to the second set of rafters +is a distance of twelve feet, in order that a gutter may be well placed +in the middle space. Between these two are again erected two sets of +rafters, the lower ends of which are likewise mortised into the beams, +which lie on the two longitudinal beams and the fourth long wall, and +are interdistant a cubit. The upper ends of the ones fifteen feet long +rest on the backs of the rafters of the first set; the ends of the +others, which are eighteen feet long, rest on the backs of the rafters +of the second set, which are longer; in this manner, in the middle of +the rafters, is a sub-structure. Upon each alternate cross-beam which is +placed upon the two longitudinal beams and the fourth long wall is +erected an upright post, and that it may be sufficiently firm it is +strengthened by means of a slanting timber. Upon these posts is laid a +long beam, upon which rests one set of middle rafters. In a similar +manner the other set of middle rafters rests on a long beam which is +placed upon other posts. Besides this, two feet above every cross-beam, +which is placed on the two longitudinal beams and the fourth long wall, +is placed a tie-beam which reaches from the first set of middle rafters +to the second set of middle rafters; upon the tie-beams is placed a +gutter hollowed out from a tree. Then from the back of each of the first +set of middle rafters a beam six feet long reaches almost to the gutter; +to the lower end of this beam is attached a piece of wood two feet long; +this is repeated with each rafter of the first set of middle rafters. +Similarly from the back of each rafter of the second set of middle +rafters a little beam, seven feet long, reaches almost to the gutter; to +the lower end of it is likewise attached a short piece of wood; this is +repeated on each rafter of the second set of middle rafters. Then in the +upper part, to the first and second sets of principal rafters are +fastened long boards, upon which are fixed the burnt tiles; and in the +same manner, in the middle part, they are fastened to the first and +second sets of middle rafters, and at the lower part to the little beams +which reach from each rafter of the first and second set of middle +rafters almost to the gutter; and, finally, to the little boards +fastened to the short pieces of wood are fixed shingles of pine-wood +extending into the gutter, so that the violent rain or melted snow may +not penetrate into the building. The substructures in the interior which +support the second set of rafters, and those on the opposite side which +support the third, being not unusual, I need not explain. + +In that part of the building against the second long wall are the +furnaces, in which exhausted liquation cakes which have already been +"dried" are smelted, that they may recover once again the appearance and +colour of copper, inasmuch as they really are copper. The remainder of +the room is occupied by the passage which leads from the door to the +furnaces, together with two other furnaces, in one of which the whole +cakes of copper are heated, and in the other the exhausted liquation +cakes are "dried" by the heat of the fire. + +Likewise, in the room between the third and seventh[5] transverse walls, +two posts are erected on rock foundation; both of them are eight feet +high and two feet wide and thick. The one is at a distance of thirteen +feet from the second long wall; the other at the same distance from the +third long wall; there is a distance of thirteen feet between them. Upon +these two posts and upon the third transverse wall are laid two +longitudinal beams, forty-one feet and one palm long, and two feet wide +and thick. Two other beams of the same length, width, and thickness are +laid upon the upright posts and upon the seventh transverse wall, and +the heads of the two long beams, where they meet, are joined with iron +staples. On these longitudinal beams are again placed twenty-one +transverse beams, thirteen feet long, a foot wide, and three palms +thick, of which the first is set on the third transverse wall, and the +last on the seventh transverse wall; the rest are laid in the space +between these two, and they are distant from one another three feet. +Into the ends of the transverse beams which face the second long wall, +are mortised the ends of the same number of rafters erected toward the +upright posts which are placed upon the second long wall, and in this +manner is made the second inclined side wall of the hood. Into the ends +of the transverse beams facing the third long wall, are mortised the +ends of the same number of rafters rising toward the rafters of the +first inclined side of the second hood, and in this manner is made the +other inclined side of the second hood. But to prevent this from falling +in upon the opposite inclined side of the hood, and that again upon the +opposite vertical one, there are many iron rods reaching from some of +the rafters to those opposite them; and this is also prevented in part +by means of a few tie-beams, extending from the back of the rafters to +the back of those which are behind them. These tie-beams are two palms +thick and wide, and have holes made through them at each end; each of +the rafters is bound round with iron bands three digits wide and half a +digit thick, which hold together the ends of the tie-beams of which I +have spoken; and so that the joints may be firm, an iron nail, passing +through the plate on both sides, is driven through the holes in the ends +of the beams. Since one weight counter-balances another, the rafters on +the opposite hoods cannot fall. The tie-beams and middle posts which +have to support the gutters and the roof, are made in every particular +as I stated above, except only that the second set of middle rafters are +not longer than the first set of middle rafters, and that the little +beams which reach from the back of each rafter of the second set of +middle rafters nearly to the gutter are not longer than the little beams +which reach from the back of each rafter of the first set of middle +rafters almost to the gutter. In this part of the building, against the +second long wall, are the furnaces in which copper is alloyed with lead, +and in which "slags" are re-smelted. Against the third long wall are the +furnaces in which silver and lead are liquated from copper. The interior +is also occupied by two cranes, of which one deposits on the ground the +cakes of copper lifted out of the moulding pans; the other lifts them +from the ground into the second furnace. + +On the third and the fourth long walls are set twenty-one beams eighteen +feet and three palms long. In mortises in them, two feet behind the +third long wall, are set the ends of the same number of rafters erected +opposite to the rafters of the other inclined wall of the second furnace +hood, and in this manner is made the third inclined wall, exactly +similar to the others. The ends of as many rafters are mortised into +these beams where they are fixed in the fourth long wall; these rafters +are erected obliquely, and rest against the backs of the preceding ones +and support the roof, which consists entirely of burnt tiles and has the +usual substructures. In this part of the building there are two rooms, +in the first of which the cakes of copper, and in the other the cakes of +lead, are stored. + +In the space enclosed between the ninth and tenth transverse walls and +the second and fifth long walls, a post twelve feet high and two feet +wide and thick is erected on a rock foundation; it is distant thirteen +feet from the second long wall, and six from the fifth long wall. Upon +this post and upon the ninth transverse wall is laid a beam thirty-three +feet and three palms long, and two palms wide and thick. Another beam, +also of the same length, width and thickness, is laid upon the same post +and upon the tenth transverse wall, and the ends of these two beams +where they meet are joined by means of iron staples. On these beams and +on the fifth long wall are placed ten cross-beams, eight feet and three +palms long, the first of which is placed on the ninth transverse wall, +the last on the tenth, the remainder in the space between them; they are +distant from one another three feet. Into the ends of the cross-beams +facing the second long wall, are mortised the ends of the same number of +rafters inclined toward the posts which stand vertically upon the second +long wall. This, again, is the manner in which the inclined side of the +furnace hood is made, just as with the others; at the top where the +fumes are emitted it is two feet distant from the vertical side. The +ends of the same number of rafters are mortised into the cross-beams, +where they are set in the fifth long wall; each of them is set up +obliquely and rests against the back of one of the preceding set; they +support the roof, made of burnt tiles. In this part of the building, +against the second long wall, are four furnaces in which lead is +separated from silver, together with the cranes by means of which the +domes are lifted from the crucibles. + +In that part of the building which lies between the first long wall and +the break in the second long wall, is the stamp with which the copper +cakes are crushed, and the four stamps with which the accretions that +are chipped off the walls of the furnace are broken up and crushed to +powder, and likewise the bricks on which the exhausted liquation cakes +of copper are stood to be "dried." This room has the usual roof, as also +has the space between the seventh transverse wall and the twelfth and +thirteenth transverse walls. + +[Illustration 499 (Hearths for melting lead cakes): A--Hearth. B--Rocks +sunk into the ground. C--Walls which protect the fourth long wall from +damage by fire. D--Dipping-pot. E--Masses of lead. F--Trolley. G--Its +wheels. H--Crane. I--Tongs. K--Wood. L--Moulds. M--Ladle. N--Pick. +O--Cakes.] + +At the sides of these rooms are the fifth, the sixth, and the third long +walls. This part of the building is divided into two parts, in the first +of which stand the little furnaces in which the artificer assays metals; +and the bone ash, together with the other powders, are kept here. In the +other room is prepared the powder from which the hearths and the +crucibles of the furnaces are made. Outside the building, at the back of +the fourth long wall, near the door to the left as you enter, is a +hearth in which smaller masses of lead are melted from large ones, that +they may be the more easily weighed; because the masses of lead, just as +much as the cakes of copper, ought to be first prepared so that they can +be weighed, and a definite weight can be melted and alloyed in the +furnaces. To begin with, the hearth in which the masses of lead are +liquefied is six feet long and five wide; it is protected on both sides +by rocks partly sunk into the earth, but a palm higher than the hearth, +and it is lined in the inside with lute. It slopes toward the middle and +toward the front, in order that the molten lead may run down and flow +out into the dipping-pot. There is a wall at the back of the hearth +which protects the fourth long wall from damage by the heat; this wall, +which is made of bricks and lute, is four feet high, three palms thick, +and five feet long at the bottom, and at the top three feet and two +palms long; therefore it narrows gradually, and in the upper part are +laid seven bricks, the middle ones of which are set upright, and the end +ones inclined; they are all thickly coated with lute. In front of the +hearth is a dipping-pot, whose pit is a foot deep, and a foot and three +palms wide at the top, and gradually narrows. When the masses of lead +are to be melted, the workman first places the wood in the hearth so +that one end of each billet faces the wall, and the other end the +dipping-pot. Then, assisted by other workmen, he pushes the mass of lead +forward with crowbars on to a low trolley, and draws it to the crane. +The trolley consists of planks fastened together, is two and one-half +feet wide and five feet long, and has two small iron axles, around which +at each end revolve small iron wheels, two palms in diameter and as many +digits wide. The trolley has a tongue, and attached to this is a rope, +by which it is drawn to the crane. The crane is exactly similar to those +in the second part of the works, except that the crane-arm is not so +long. The tongs in whose jaws[6] the masses of lead are seized, are two +feet a palm and two digits long; both of the jaws, when struck with a +hammer, impinge upon the mass and are driven into it. The upper part of +both handles of the tongs are curved back, the one to the right, the +other to the left, and each handle is engaged in one of the lowest links +of two short chains, which are three links long. The upper links are +engaged in a large round ring, in which is fixed the hook of a chain let +down from the pulley of the crane-arm. When the crank of the crane is +turned, the mass is lifted and is carried by the crane-arm to the hearth +and placed on the wood. The workmen wheel up one mass after another and +place them in a similar manner on the wood of the hearth; masses which +weigh a total of about a hundred and sixty _centumpondia_[7] are usually +placed upon the wood and melted at one time. Then a workman throws +charcoal on the masses, and all are made ready in the evening. If he +fears that it may rain, he covers it up with a cover, which may be moved +here and there; at the back this cover has two legs, so that the rain +which it collects may flow down the slope on to the open ground. Early +in the morning of the following day, he throws live coals on the +charcoal with a shovel, and by this method the masses of lead melt, and +from time to time charcoal is added. The lead, as soon as it begins to +run into the dipping-pot, is ladled out with an iron ladle into copper +moulds such as the refiners generally use. If it does not cool +immediately he pours water over it, and then sticks the pointed pick +into it and pulls it out. The pointed end of the pick is three palms +long and the round end is two digits long. It is necessary to smear the +moulds with a wash of lute, in order that, when they have been turned +upside down and struck with the broad round end of the pick, the cakes +of lead may fall out easily. If the moulds are not washed over with the +lute, there is a risk that they may be melted by the lead and let it +through. Others take hold of a billet of wood with their left hand, and +with the heavy lower end of it they pound the mould, and with the right +hand they stick the point of the pick into the cake of lead, and thus +pull it out. Then immediately the workman pours other lead into the +empty moulds, and this he does until the work of melting the lead is +finished. When the lead is melted, something similar to litharge is +produced; but it is no wonder that it should be possible to make it in +this case, when it used formerly to be produced at Puteoli from lead +alone when melted by a fierce fire in the cupellation furnace.[8] +Afterward these cakes of lead are carried into the lead store-room. + +[Illustration 501 (Stamp-mill for breaking copper cakes): A--Block of +wood. B--Upright posts. C--Transverse beams. D--Head of the stamp. +E--Its tooth. F--The hole in the stamp-stem. G--Iron bar. H--Masses of +lead. I--The bronze saddle. K--Axle. L--Its arms. M--Little iron axle. +N--Bronze pipe.] + +The cakes of copper, put into wheelbarrows, are carried into the third +part of the building, where each is laid upon a saddle, and is broken up +by the impact of successive blows from the iron-shod stamp. This machine +is made by placing upon the ground a block of oak, five feet long and +three feet wide and thick; it is cut out in the middle for a length of +two feet and two palms, a width of two feet, and a depth of three palms +and two digits, and is open in front; the higher part of it is at the +back, and the wide part lies flat in the block. In the middle of it is +placed a bronze saddle. Its base is a palm and two digits wide, and is +planted between two masses of lead, and extends under them to a depth of +a palm on both sides. The whole saddle is three palms and two digits +wide, a foot long, and two palms thick. Upon each end of the block +stands a post, a cubit wide and thick, the upper end of which is +somewhat cut away and is mortised into the beams of the building. At a +height of four feet and two digits above the block there are joined to +the posts two transverse beams, each of which is three palms wide and +thick; their ends are mortised into the upright posts, and holes are +bored through them; in the holes are driven iron claves, horned in front +and so driven into the post that one of the horns of each points upward +and the other downward; the other end of each clavis is perforated, and +a wide iron wedge is inserted and driven into the holes, and thus holds +the transverse beams in place. These transverse beams have in the middle +a square opening three palms and half a digit wide in each direction, +through which the iron-shod stamp passes. At a height of three feet and +two palms above these transverse beams there are again two beams of the +same kind, having also a square opening and holding the same stamp. This +stamp is square, eleven feet long, three palms wide and thick; its iron +shoe is a foot and a palm long; its head is two palms long and wide, a +palm two digits thick at the top, and at the bottom the same number of +digits, for it gradually narrows. But the tail is three palms long; +where the head begins is two palms wide and thick, and the further it +departs from the same the narrower it becomes. The upper part is +enclosed in the stamp-stem, and it is perforated so that an iron bolt +may be driven into it; it is bound by three rectangular iron bands, the +lowest of which, a palm wide, is between the iron shoe and the head of +the stamp; the middle band, three digits wide, follows next and binds +round the head of the stamp, and two digits above is the upper one, +which is the same number of digits wide. At a distance of two feet and +as many digits above the lowest part of the iron shoe, is a rectangular +tooth, projecting from the stamp for a distance of a foot and a palm; it +is two palms thick, and when it has extended to a distance of six digits +from the stamp it is made two digits narrower. At a height of three +palms upward from the tooth there is a round hole in the middle of the +stamp-stem, into which can be thrust a round iron bar two feet long and +a digit and a half in diameter; in its hollow end is fixed a wooden +handle two palms and the same number of digits long. The bar rests on +the lower transverse beam, and holds up the stamp when it is not in use. +The axle which raises the stamp has on each side two arms, which are two +palms and three digits distant from each other, and which project from +the axle a foot, a palm and two digits; penetrating through them are +bolts, driven in firmly; the arms are each a palm and two digits wide +and thick, and their round heads, for a foot downward on either side, +are covered with iron plates of the same width as the arms and fastened +by iron nails. The head of each arm has a round hole, into which is +inserted an iron pin, passing through a bronze pipe; this little axle +has at the one end a wide head, and at the other end a perforation +through which is driven an iron nail, lest this little axle should fall +out of the arms. The bronze pipe is two palms long and one in diameter; +the little iron axle penetrates through its round interior, which is two +digits in diameter. The bronze pipe not only revolves round the little +iron axle, but it also rotates with it; therefore, when the axle +revolves, the little axle and the bronze tube in their turn raise the +tooth and the stamp. When the little iron axle and the bronze pipe have +been taken out of the arms, the tooth of the stamps is not raised, and +other stamps may be raised without this one. Further on, a drum with +spindles fixed around the axle of a water-wheel moves the axle of a +toothed drum, which depresses the sweeps of the bellows in the adjacent +fourth part of the building; but it turns in the contrary direction; for +the axis of the drum which raises the stamps turns toward the north, +while that one which depresses the sweeps of the bellows turns toward +the south. + +[Illustration 504 (Hearths for heating copper cakes): A--Back wall. +B--Walls at the sides. C--Upright posts. D--Chimney. E--The cakes +arranged. F--Iron plates. G--Rocks. H--Rabble with two prongs. +I--Hammers.] + +Those cakes which are too thick to be rapidly broken by blows from the +iron-shod stamp, such as are generally those which have settled in the +bottom of the crucible,[9] are carried into the first part of the +building. They are there heated in a furnace, which is twenty-eight feet +distant from the second long wall and twelve feet from the second +transverse wall. The three sides of this furnace are built of +rectangular rocks, upon which bricks are laid; the back furnace wall is +three feet and a palm high, and the rear of the side walls is the same; +the side walls are sloping, and where the furnace is open in front they +are only two feet and three palms high; all the walls are a foot and a +palm thick. Upon these walls stand upright posts not less thick, in +order that they may bear the heavy weight placed upon them, and they are +covered with lute; these posts support the sloping chimney and penetrate +through the roof. Moreover, not only the ribs of the chimney, but also +the rafters, are covered thickly with lute. The hearth of the furnace is +six feet long on each side, is sloping, and is paved with bricks. The +cakes of copper are placed in the furnace and heated in the following +way. They are first of all placed in the furnace in rows, with as many +small stones the size of an egg between, so that the heat of the fire +can penetrate through the spaces between them; indeed, those cakes which +are placed at the bottom of the crucible are each raised upon half a +brick for the same reason. But lest the last row, which lies against the +mouth of the furnace, should fall out, against the mouth are placed iron +plates, or the copper cakes which are the first taken from the crucible +when copper is made, and against them are laid exhausted liquation cakes +or rocks. Then charcoal is thrown on the cakes, and then live coals; at +first the cakes are heated by a gentle fire, and afterward more charcoal +is added to them until it is at times three-quarters of a foot deep. A +fiercer fire is certainly required to heat the hard cakes of copper than +the fragile ones. When the cakes have been sufficiently heated, which +usually occurs within the space of about two hours, the exhausted +liquation cakes or the rocks and the iron plate are removed from the +mouth of the furnace. Then the hot cakes are taken out row after row +with a two-pronged rabble, such as the one which is used by those who +"dry" the exhausted liquation cakes. Then the first cake is laid upon +the exhausted liquation cakes, and beaten by two workmen with hammers +until it breaks; the hotter the cakes are, the sooner they are broken +up; the less hot, the longer it takes, for now and then they bend into +the shape of copper basins. When the first cake has been broken, the +second is put on to the other fragments and beaten until it breaks into +pieces, and the rest of the cakes are broken up in the same manner in +due order. The head of the hammer is three palms long and one wide, and +sharpened at both ends, and its handle is of wood three feet long. When +they have been broken by the stamp, if cold, or with hammers if hot, the +fragments of copper or the cakes are carried into the store-room for +copper. + +The foreman of the works, according to the different proportions of +silver in each _centumpondium_ of copper, alloys it with lead, without +which he could not separate the silver from the copper.[10] If there be +a moderate amount of silver in the copper, he alloys it fourfold; for +instance, if in three-quarters of a _centumpondium_ of copper there is +less than the following proportions, _i.e._: half a _libra_ of silver, +or half a _libra_ and a _sicilicus_, or half a _libra_ and a +_semi-uncia_, or half a _libra_ and _semi-uncia_ and a _sicilicus_, then +rich lead--that is, that from which the silver has not yet been +separated--is added, to the amount of half a _centumpondium_ or a whole +_centumpondium_, or a whole and a half, in such a way that there may be +in the copper-lead alloy some one of the proportions of silver which I +have just mentioned, which is the first alloy. To this "first" alloy is +added such a weight of de-silverized lead or litharge as is required to +make out of all of these a single liquation cake that will contain +approximately two _centumpondia_ of lead; but as usually from one +hundred and thirty _librae_ of litharge only one hundred _librae_ of +lead are made, a greater proportion of litharge than of de-silverized +lead is added as a supplement. Since four cakes of this kind are placed +at the same time into the furnace in which the silver and lead is +liquated from copper, there will be in all the cakes three +_centumpondia_ of copper and eight _centumpondia_ of lead. When the lead +has been liquated from the copper, it weighs six _centumpondia_, in each +_centumpondium_ of which there is a quarter of a _libra_ and almost a +_sicilicus_ of silver. Only seven _unciae_ of the silver remain in the +exhausted liquation cakes and in that copper-lead alloy which we call +"liquation thorns"; they are not called by this name so much because +they have sharp points as because they are base. If in three-quarters of +a _centumpondium_ of copper there are less than seven _uncia_ and a +_semi-uncia_ or a _bes_ of silver, then so much rich lead must be added +as to make in the copper and lead alloy one of the proportions of silver +which I have already mentioned. This is the "second" alloy. To this is +again to be added as great a weight of de-silverized lead, or of +litharge, as will make it possible to obtain from that alloy a liquation +cake containing two and a quarter _centumpondia_ of lead, in which +manner in four of these cakes there will be three _centumpondia_ of +copper and nine _centumpondia_ of lead. The lead which liquates from +these cakes weighs seven _centumpondia_, in each _centumpondium_ of +which there is a quarter of a _libra_ of silver and a little more than a +_sicilicus_. About seven _unciae_ of silver remain in the exhausted +liquation cakes and in the liquation thorns, if we may be allowed to +make common the old name (_spinae_ = thorns) and bestow it upon a new +substance. If in three-quarters of a _centumpondium_ of copper there is +less than three-quarters of a _libra_ of silver, or three-quarters and a +_semi-uncia_, then as much rich lead must be added as will produce one +of the proportions of silver in the copper-lead alloy above mentioned; +this is the "third" alloy. To this is added such an amount of +de-silverized lead or of litharge, that a liquation cake made from it +contains in all two and three-quarters _centumpondia_ of lead. In this +manner four such cakes will contain three _centumpondia_ of copper and +eleven _centumpondia_ of lead. The lead which these cakes liquate, when +they are melted in the furnace, weighs about nine _centumpondia_, in +each _centumpondium_ of which there is a quarter of a _libra_ and more +than a _sicilicus_ of silver; and seven _unciae_ of silver remain in the +exhausted liquation cakes and in the liquation thorns. If, however, in +three-quarters of a _centumpondium_ of copper there is less than +ten-twelfths of a _libra_ or ten-twelfths of a _libra_ and a +_semi-uncia_ of silver, then such a proportion of rich lead is added as +will produce in the copper-lead alloy one of the proportions of silver +which I mentioned above; this is the "fourth" alloy. To this is added +such a weight of de-silverized lead or of litharge, that a liquation +cake made from it contains three _centumpondia_ of lead, and in four +cakes of this kind there are three _centumpondia_ of copper and twelve +_centumpondia_ of lead. The lead which is liquated therefrom weighs +about ten _centumpondia_, in each _centumpondium_ of which there is a +quarter of a _libra_ and more than a _semi-uncia_ of silver, or seven +_unciae_; a _bes_, or seven _unciae_ and a _semi-uncia_, of silver +remain in the exhausted liquation cakes and in the liquation thorns. + +[Illustration 508 (Blast Furnaces): A--Furnace in which "slags" are +re-smelted. B--Furnace in which copper is alloyed with lead. C--Door. +D--Forehearths on the ground. E--Copper moulds. F--Rabble. G--Hook. +H--Cleft stick. I--Arm of the crane. K--The hook of its chain.] + +Against the second long wall in the second part of the building, whose +area is eighty feet long by thirty-nine feet wide, are four furnaces in +which the copper is alloyed with lead, and six furnaces in which "slags" +are re-smelted. The interior of the first kind of furnace is a foot and +three palms wide, two feet three digits long; and of the second is a +foot and a palm wide and a foot three palms and a digit long. The side +walls of these furnaces are the same height as the furnaces in which +gold or silver ores are smelted. As the whole room is divided into two +parts by upright posts, the front part must have, first, two furnaces in +which "slags" are re-melted; second, two furnaces in which copper is +alloyed with lead; and third, one furnace in which "slags" are +re-melted. The back part of the room has first, one furnace in which +"slags" are re-melted; next, two furnaces in which copper is alloyed +with lead; and third, two furnaces in which "slags" are re-melted. Each +of these is six feet distant from the next; on the right side of the +first is a space of three feet and two palms, and on the left side of +the last one of seven feet. Each pair of furnaces has a common door, six +feet high and a cubit wide, but the first and the tenth furnace each has +one of its own. Each of the furnaces is set in an arch of its own in the +back wall, and in front has a forehearth pit; this is filled with a +powder compound rammed down and compressed in order to make a crucible. +Under each furnace is a hidden receptacle for the moisture,[11] from +which a vent is made through the back wall toward the right, which +allows the vapour to escape. Finally, to the right, in front, is the +copper mould into which the copper-lead alloy is poured from the +forehearth, in order that liquation cakes of equal weight may be made. +This copper mould is a digit thick, its interior is two feet in diameter +and six digits deep. Behind the second long wall are ten pairs of +bellows, two machines for compressing them, and twenty instruments for +inflating them. The way in which these should be made may be understood +from Book IX. + +The smelter, when he alloys copper with lead, with his hand throws into +the heated furnace, first the large fragments of copper, then a +basketful of charcoal, then the smaller fragments of copper. When the +copper is melted and begins to run out of the tap-hole into the +forehearth, he throws litharge into the furnace, and, lest part of it +should fly away, he first throws charcoal over it, and lastly lead. As +soon as he has thrown into the furnace the copper and the lead, from +which alloy the first liquation cake is made, he again throws in a +basket of charcoal, and then fragments of copper are thrown over them, +from which the second cake may be made. Afterward with a rabble he skims +the "slag" from the copper and lead as they flow into the forehearth. +Such a rabble is a board into which an iron bar is fixed; the board is +made of elder-wood or willow, and is ten digits long, six wide, and one +and a half digits thick; the iron bar is three feet long, and the wooden +handle inserted into it is two and a half feet long. While he purges the +alloy and pours it out with a ladle into the copper mould, the fragments +of copper from which he is to make the second cake are melting. As soon +as this begins to run down he again throws in litharge, and when he has +put on more charcoal he adds the lead. This operation he repeats until +thirty liquation cakes have been made, on which work he expends nine +hours, or at most ten; if more than thirty cakes must be made, then he +is paid for another shift when he has made an extra thirty. + +At the same time that he pours the copper-lead alloy into the copper +mould, he also pours water slowly into the top of the mould. Then, with +a cleft stick, he takes a hook and puts its straight stem into the +molten cake. The hook itself is a digit and a half thick; its straight +stem is two palms long and two digits wide and thick. Afterward he pours +more water over the cakes. When they are cold he places an iron ring in +the hook of the chain let down from the pulley of the crane arm; the +inside diameter of this ring is six digits, and it is about a digit and +a half thick; the ring is then engaged in the hook whose straight stem +is in the cake, and thus the cake is raised from the mould and put into +its place. + +The copper and lead, when thus melted, yield a small amount of +"slag"[12] and much litharge. The litharge does not cohere, but falls to +pieces like the residues from malt from which beer is made. _Pompholyx_ +adheres to the walls in white ashes, and to the sides of the furnace +adheres _spodos_. + +In this practical manner lead is alloyed with copper in which there is +but a moderate portion of silver. If, however, there is much silver in +it, as, for instance, two _librae_, or two _librae_ and a _bes_, to the +_centumpondium_,--which weighs one hundred and thirty-three and a third +_librae_, or one hundred and forty-six _librae_ and a _bes_,[13]--then +the foreman of the works adds to a _centumpondium_ of such copper three +_centumpondia_ of lead, in each _centumpondium_ of which there is a +third of a _libra_ of silver, or a third of a _libra_ and a +_semi-uncia_. In this manner three liquation cakes are made, which +contain altogether three _centumpondia_ of copper and nine +_centumpondia_ of lead.[14] The lead, when it has been liquated from the +copper, weighs seven _centumpondia_; and in each _centumpondium_--if the +_centumpondium_ of copper contain two _librae_ of silver, and the lead +contain a third of a _libra_--there will be a _libra_ and a sixth and +more than a _semi-uncia_ of silver; while in the exhausted liquation +cakes, and in the liquation thorns, there remains a third of a _libra_. +If a _centumpondium_ of copper contains two _librae_ and a _bes_ of +silver, and the lead a third of a _libra_ and a _semi-uncia_, there will +be in each liquation cake one and a half _librae_ and a _semi-uncia_, +and a little more than a _sicilicus_ of silver. In the exhausted +liquation cakes there remain a third of a _libra_ and a _semi-uncia_ of +silver. + +[Illustration 510 (Furnaces enriching copper bottoms): A--Furnace. +B--Forehearth. C--Dipping-Pot. D--Cakes.] + +If there be in the copper only a minute proportion of silver, it cannot +be separated easily until it has been re-melted in other furnaces, so +that in the "bottoms" there remains more silver and in the "tops" +less.[15] This furnace, vaulted with unbaked bricks, is similar to an +oven, and also to the cupellation furnace, in which the lead is +separated from silver, which I described in the last book. The crucible +is made of ashes, in the same manner as in the latter, and in the front +of the furnace, three feet above the floor of the building, is the mouth +out of which the re-melted copper flows into a forehearth and a +dipping-pot. On the left side of the mouth is an aperture, through which +beech-wood may be put into the furnace to feed the fire. If in a +_centumpondium_ of copper there were a sixth of a _libra_ and a +_semi-uncia_ of silver, or a quarter of a _libra_, or a quarter of a +_libra_ and a _semi-uncia_--there is re-melted at the same time +thirty-eight _centumpondia_ of it in this furnace, until there remain in +each _centumpondium_ of the copper "bottoms" a third of a _libra_ and a +_semi-uncia_ of silver. For example, if in each _centumpondium_ of +copper not yet re-melted, there is a quarter of a _libra_ and a +_semi-uncia_ of silver, then the thirty-eight _centumpondia_ that are +smelted together must contain a total of eleven _librae_ and an _uncia_ +of silver. Since from fifteen _centumpondia_ of re-melted copper there +was a total of four and a third _librae_ and a _semi-uncia_ of silver, +there remain only two and a third _librae_. Thus there is left in the +"bottoms," weighing twenty-three _centumpondia_, a total of eight and +three-quarter _librae_ of silver. Therefore, each _centumpondium_ of +this contains a third of a _libra_ and a _semi-uncia_, a _drachma_, and +the twenty-third part of a _drachma_ of silver; from such copper it is +profitable to separate the silver. In order that the master may be more +certain of the number of _centumpondia_ of copper in the "bottoms," he +weighs the "tops" that have been drawn off from it; the "tops" were +first drawn off into the dipping-pot, and cakes were made from them. +Fourteen hours are expended on the work of thus dividing the copper. The +"bottoms," when a certain weight of lead has been added to them, of +which alloy I shall soon speak, are melted in the blast furnace; +liquation cakes are then made, and the silver is afterward separated +from the copper. The "tops" are subsequently melted in the blast +furnace, and re-melted in the refining furnace, in order that red copper +shall be made[16]; and the "tops" from this are again smelted in the +blast furnace, and then again in the refining furnace, that therefrom +shall be made _caldarium_ copper. But when the copper, yellow or red or +_caldarium_ is re-smelted in the refining furnace, forty _centumpondia_ +are placed in it, and from it they make at least twenty, and at most +thirty-five, _centumpondia_. About twenty-two _centumpondia_ of +exhausted liquation cakes and ten of yellow copper and eight of red, are +simultaneously placed in this latter furnace and smelted, in order that +they may be made into refined copper. + +The copper "bottoms" are alloyed in three different ways with lead.[17] +First, five-eighths of a _centumpondium_ of copper and two and +three-quarters _centumpondia_ of lead are taken; and since one liquation +cake is made from this, therefore two and a half _centumpondia_ of +copper and eleven _centumpondia_ of lead make four liquation cakes. +Inasmuch as in each _centumpondium_ of copper there is a third of a +_libra_ of silver, there would be in the whole of the copper +ten-twelfths of a _libra_ of silver; to these are added four +_centumpondia_ of lead re-melted from "slags," each _centumpondium_ of +which contains a _sicilicus_ and a _drachma_ of silver, which weights +make up a total of an _uncia_ and a half of silver. There is also added +seven _centumpondia_ of de-silverized lead, in each _centumpondium_ of +which there is a _drachma_ of silver; therefore in the four cakes of +copper-lead alloy there is a total of a _libra_, a _sicilicus_ and a +_drachma_ of silver. In each single _centumpondium_ of lead, after it +has been liquated from the copper, there is an _uncia_ and a _drachma_ +of silver, which alloy we call "poor" argentiferous lead, because it +contains but little silver. But as five cakes of that kind are placed +together in the furnace, they liquate from them usually as much as nine +and three-quarters _centumpondia_ of poor argentiferous lead, in each +_centumpondium_ of which there is an _uncia_ and a _drachma_ of silver, +or a total of ten _unciae_ less four _drachmae_. Of the liquation thorns +there remain three _centumpondia_, in each _centumpondium_ of which +there are three _sicilici_ of silver; and there remain four +_centumpondia_ of exhausted liquation cakes, each _centumpondium_ of +which contains a _semi-uncia_ or four and a half _drachmae_. Inasmuch as +in a _centumpondium_ of copper "bottoms" there is a third of a _libra_ +and a _semi-uncia_ of silver, in five of those cakes there must be more +than one and a half _unciae_ and half a _drachma_ of silver. + +Then, again, from another two and a half _centumpondia_ of copper +"bottoms," together with eleven _centumpondia_ of lead, four liquation +cakes are made. If in each _centumpondium_ of copper there was a third +of a _libra_ of silver, there would be in the whole of the +_centumpondia_ of base metal five-sixths of a _libra_ of the precious +metal. To this copper is added eight _centumpondia_ of poor +argentiferous lead, each _centumpondium_ of which contains an _uncia_ +and a _drachma_ of silver, or a total of three-quarters of a _libra_ of +silver. There is also added three _centumpondia_ of de-silverized lead, +in each _centumpondium_ of which there is a _drachma_ of silver. +Therefore, four liquation cakes contain a total of a _libra_, seven +_unciae_, a _sicilicus_ and a _drachma_ of silver; thus each +_centumpondium_ of lead, when it has been liquated from the copper, +contains an _uncia_ and a half and a _sicilicus_ of silver, which alloy +we call "medium" silver-lead. + +Then, again, from another two and a half _centumpondia_ of copper +"bottoms," together with eleven _centumpondia_ of lead, they make four +liquation cakes. If in each _centumpondium_ of copper there were +likewise a third of a _libra_ of silver, there will be in all the weight +of the base metal five-sixths of a _libra_ of the precious metal. To +this is added nine _centumpondia_ of medium silver-lead, each +_centumpondium_ of which contains an _uncia_ and a half and a +_sicilicus_ of silver; or a total of a _libra_ and a quarter and a +_semi-uncia_ and a _sicilicus_ of silver. And likewise they add two +_centumpondia_ of poor silver-lead, in each of which there is an _uncia_ +and a _drachma_ of silver. Therefore the four liquation cakes contain +two and a third _librae_ of silver. Each _centumpondium_ of lead, when +it has been liquated from the copper, contains a sixth of a _libra_ and +a _semi-uncia_ and a _drachma_ of silver. This alloy we call "rich" +silver-lead; it is carried to the cupellation furnace, in which lead is +separated from silver. I have now mentioned in how many ways copper +containing various proportions of silver is alloyed with lead, and how +they are melted together in the furnace and run into the casting pan. + +[Illustration 514 (Crane for liquation cakes): A--Crane. B--Drum +consisting of rundles. C--Toothed drum. D--Trolley and its wheels. +E--Triangular board. F--Cakes. G--Chain of the crane. H--Its hook. +I--Ring. K--The tongs.] + +Now I will speak of the method by which lead is liquated from copper +simultaneously with the silver. The liquation cakes are raised from the +ground with the crane, and placed on the copper plates of the furnaces. +The hook of the chain let down from the arm of the crane, is inserted in +a ring of the tongs, one jaw of which has a tooth; a ring is engaged in +each of the handles of the tongs, and these two rings are engaged in a +third, in which the hook of the chain is inserted. The tooth on the one +jaw of the tongs is struck by a hammer, and driven into the hole in the +cake, at the point where the straight end of the hook was driven into +it when it was lifted out of the copper mould; the other jaw of the +tongs, which has no tooth, squeezes the cake, lest the tooth should fall +out of it; the tongs are one and a half feet long, each ring is a digit +and a half thick, and the inside is a palm and two digits in diameter. +Those cranes by which the cakes are lifted out of the copper pans and +placed on the ground, and lifted up again from there and placed in the +furnaces, are two in number--one in the middle space between the third +transverse wall and the two upright posts, and the other in the middle +space between the same posts and the seventh transverse wall. The +rectangular crane-post of both of these is two feet wide and thick, and +is eighteen feet from the third long wall, and nineteen from the second +long wall. There are two drums in the framework of each--one drum +consisting of rundles, the other being toothed. The crane-arm of each +extends seventeen feet, three palms and as many digits from the post. +The trolley of each crane is two feet and as many palms long, a foot and +two digits wide, and a palm and two digits thick; but where it runs +between the beams of the crane-arm it is three digits wide and a palm +thick; it has five notches, in which turn five brass wheels, four of +which are small, and the fifth much larger than the rest. The notches in +which the small wheels turn are two palms long and as much as a palm +wide; those wheels are a palm wide and a palm and two digits in +diameter; four of the notches are near the four corners of the trolley; +the fifth notch is between the two front ones, and it is two palms back +from the front. Its pulley is larger than the rest, and turns in its own +notch; it is three palms in diameter and one palm wide, and grooved on +the circumference, so that the iron chain may run in the groove. The +trolley has two small axles, to the one in front are fastened three, and +to the one at the back, the two wheels; two wheels run on the one beam +of the crane-arm, and two on the other; the fifth wheel, which is larger +than the others, runs between those two beams. Those people who have no +cranes place the cakes on a triangular board, to which iron cleats are +affixed, so that it will last longer; the board has three iron chains, +which are fixed in an iron ring at the top; two workmen pass a pole +through the ring and carry it on their shoulders, and thus take the cake +to the furnace in which silver is separated from copper. + +From the vicinity of the furnaces in which copper is mixed with lead and +the "slags" are re-melted, to the third long wall, are likewise ten +furnaces, in which silver mixed with lead is separated from copper. If +this space is eighty feet and two palms long, and the third long wall +has in the centre a door three feet and two palms wide, then the spaces +remaining at either side of the door will be thirty-eight feet and two +palms; and if each of the furnaces occupies four feet and a palm, then +the interval between each furnace and the next one must be a foot and +three palms; thus the width of the five furnaces and four interspaces +will be twenty-eight feet and a palm. Therefore, there remain ten feet +and a palm, which measurement is so divided that there are five feet and +two digits between the first furnace and the transverse wall, and as +many feet and digits between the fifth furnace and the door; similarly +in the other part of the space from the door to the sixth furnace, there +must be five feet and two digits, and from the tenth furnace to the +seventh transverse wall, likewise, five feet and two digits. The door is +six feet and two palms high; through it the foreman of the _officina_ +and the workmen enter the store-room in which the silver-lead alloy is +kept. + +[Illustration 517 (Liquation Furnace): A--Sole-stones. B--Rectangular +stones. C--Copper plates. D--Front panel. E--Side panels. F--Bar. +G--Front end of the long iron rods. H--Short chain. I--Hooked rod. +K--Wall which protects the third long wall from injury by fire. L--Third +long wall. M--Feet of the panels. N--Iron blocks. O--Cakes. P--Hearth. +Q--Receiving-pit.] + +Each furnace has a bed, a hearth, a rear wall, two sides and a front, +and a receiving-pit. The bed consists of two sole-stones, four +rectangular stones, and two copper plates; the sole-stones are five feet +and a palm long, a cubit wide, a foot and a palm thick, and they are +sunk into the ground, so that they emerge a palm and two digits; they +are distant from each other about three palms, yet the distance is +narrower at the back than the front. Each of the rectangular stones is +two feet and as many palms long, a cubit wide, and a cubit thick at the +outer edge, and a foot and a palm thick on the inner edge which faces +the hearth, thus they form an incline, so that there is a slope to the +copper plates which are laid upon them. Two of these rectangular stones +are placed on one sole-stone; a hole is cut in the upper edge of each, +and into the holes are placed iron clamps, and lead is poured in; they +are so placed on the sole-stones that they project a palm at the sides, +and at the front the sole-stones project to the same extent; if +rectangular stones are not available, bricks are laid in their place. +The copper plates are four feet two palms and as many digits long, a +cubit wide, and a palm thick; each edge has a protuberance, one at the +front end, the other at the back; these are a palm and three digits +long, and a palm wide and thick. The plates are so laid upon the +rectangular stones that their rear ends are three digits from the third +long wall; the stones project beyond the plate the same number of digits +in front, and a palm and three digits at the sides. When the plates have +been joined, the groove which is between the protuberances is a palm and +three digits wide, and four feet long, and through it flows the +silver-lead which liquates from the cakes. When the plates are corroded +either by the fire or by the silver-lead, which often adheres to them in +the form of stalactites, and is chipped off, they are exchanged, the +right one being placed to the left, and the left one, on the contrary, +to the right; but the left side of the plates, which, when the fusion of +the copper took place, came into contact with the copper, must lie flat; +so that when the exchange of the plates has been carried out, the +protuberances, which are thus on the underside, raise the plate from the +stones, and they have to be partially chipped off, lest they should +prove an impediment to the work; and in each of their places is laid a +piece of iron, three palms long, a digit thick at both ends, and a palm +thick in the centre for the length of a palm and three digits. + +The passage under the plates between the rectangular stones is a foot +wide at the back, and a foot and a palm wide at the front, for it +gradually widens out. The hearth, which is between the sole-stones, is +covered with a bed of hearth-lead, taken from the crucible in which lead +is separated from silver. The rear end is the highest, and should be so +high that it reaches to within six digits of the plates, from which +point it slopes down evenly to the front end, so that the argentiferous +lead alloy which liquates from the cakes can flow into the +receiving-pit. The wall built against the third long wall in order to +protect it from injury by fire, is constructed of bricks joined together +with lute, and stands on the copper plates; this wall is two feet, a +palm and two digits high, two palms thick, and three feet, a palm and +three digits wide at the bottom, for it reaches across both of them; at +the top it is three feet wide, for it rises up obliquely on each side. +At each side of this wall, at a height of a palm and two digits above +the top of it, there is inserted in a hole in the third long wall a +hooked iron rod, fastened in with molten lead; the rod projects two +palms from the wall, and is two digits wide and one digit thick; it has +two hooks, the one at the side, the other at the end. Both of these +hooks open toward the wall, and both are a digit thick, and both are +inserted in the last, or the adjacent, links of a short iron chain. This +chain consists of four links, each of which is a palm and a digit long +and half a digit thick; the first link is engaged in the first hole in a +long iron rod, and one or other of the remaining three links engages the +hook of the hooked rod. The two long rods are three feet and as many +palms and digits long, two digits wide, and one digit thick; both ends +of both of these rods have holes, the back one of which is round and a +digit in diameter, and in this is engaged the first link of the chain as +I have stated; the hole at the front end is two digits and a half long +and a digit and a half wide. This end of each rod is made three digits +wide, while for the rest of its length it is only two digits, and at the +back it is two and a half digits. Into the front hole of each rod is +driven an iron bar, which is three feet and two palms long, two digits +wide and one thick; in the end of this bar are five small square holes, +two-thirds of a digit square; each hole is distant from the other half a +digit, the first being at a distance of about a digit from the end. Into +one of these holes the refiner drives an iron pin; if he should desire +to make the furnace narrower, then he drives it into the last hole; if +he should desire to widen it, then into the first hole; if he should +desire to contract it moderately, then into one of the middle holes. For +the same reason, therefore, the hook is sometimes inserted into the last +link of the chain, and sometimes into the third or the second. The +furnace is widened when many cakes are put into it, and contracted when +there are but few, but to put in more than five is neither usual nor +possible; indeed, it is because of thin cakes that the walls are +contracted. The bar has a hump, which projects a digit on each side at +the back, of the same width and thickness as itself. These humps +project, lest the bar should slip through the hole of the right-hand +rod, in which it remains fixed when it, together with the rods, is not +pressing upon the furnace walls. + +[Illustration 519 (Liquation Furnaces): A--Furnace in which the +operation of liquation is being performed. B--Furnace in which it is not +being performed. C--Receiving-pit. D--Moulds. E--Cakes. F--Liquation +thorns.] + +There are three panels to the furnace--two at the sides, one in front +and another at the back. Those which are at the sides are three feet and +as many palms and two digits long, and two feet high; the front one is +two feet and a palm and three digits long, and, like the side ones, two +feet high. Each consists of iron bars, of feet, and of iron plates. +Those which are at the side have seven bars, the lower and upper of +which are of the same length as the panels; the former holds up the +upright bars; the latter is placed upon them; the uprights are five in +number, and have the same height as the panels; the middle ones are +inserted into holes in the upper and lower bars; the outer ones are made +of one and the same bar as the lower and upper ones. They are two digits +wide and one thick. The front panel has five bars; the lower one holds +similar uprights, but there are three of them only; the upper bar is +placed on them. Each of these panels has two feet fixed at each end of +the lower bar, and these are two palms long, one wide, and a digit +thick. The iron plates are fastened to the inner side of the bars with +iron wire, and they are covered with lute, so that they may last longer +and may be uninjured by the fire. There are, besides, iron blocks three +palms long, one wide, and a digit and a half thick; the upper surface of +these is somewhat hollowed out, so that the cakes may stand in them; +these iron blocks are dipped into a vessel in which there is clay mixed +with water, and they are used only for placing under the cakes of copper +and lead alloy made in the furnaces. There is more silver in these than +in those which are made of liquation thorns, or furnace accretions, or +re-melted "slags." Two iron blocks are placed under each cake, in order +that, by raising it up, the fire may bring more force to bear upon it; +the one is put on the right bed-plate, the other on the left. Finally, +outside the hearth is the receiving-pit, which is a foot wide and three +palms deep; when this is worn away it is restored with lute alone, which +easily retains the lead alloy. + +If four liquation cakes are placed on the plates of each furnace, then +the iron blocks are laid under them; but if the cakes are made from +copper "bottoms," or from liquation thorns, or from the accretions or +"slags," of which I have partly written above and will further describe +a little later, there are five of them, and because they are not so +large and heavy, no blocks are placed under them. Pieces of charcoal six +digits long are laid between the cakes, lest they should fall one +against the other, or lest the last one should fall against the wall +which protects the third long wall from injury by fire. In the middle +empty spaces, long and large pieces of charcoal are likewise laid. Then +when the panels have been set up, and the bar has been closed, the +furnace is filled with small charcoal, and a wicker basket full of +charcoal is thrown into the receiving-pit, and over that are thrown live +coals; soon afterward the burning coal, lifted up in a shovel, is spread +over all parts of the furnace, so that the charcoal in it may be +kindled; any charcoal which remains in the receiving-pit is thrown into +the passage, so that it may likewise be heated. If this has not been +done, the silver-lead alloy liquated from the cakes is frozen by the +coldness of the passage, and does not run down into the receiving-pit. + +After a quarter of an hour the cakes begin to drip silver-lead +alloy,[18] which runs down through the openings between the copper +plates into the passage. When the long pieces of charcoal have burned +up, if the cakes lean toward the wall, they are placed upright again +with a hooked bar, but if they lean toward the front bar they are +propped up by charcoal; moreover, if some cakes shrink more than the +rest, charcoal is added to the former and not to the others. The silver +drips together with the lead, for both melt more rapidly than copper. +The liquation thorns do not flow away, but remain in the passage, and +should be turned over frequently with a hooked bar, in order that the +silver-lead may liquate away from them and flow down into the receiving +pit; that which remains is again melted in the blast furnace, while that +which flows into the receiving pit is at once carried with the remaining +products to the cupellation furnace, where the lead is separated from +the silver. The hooked bar has an iron handle two feet long, in which is +set a wooden one four feet long. The silver-lead which runs out into the +receiving-pit is poured out by the refiner with a bronze ladle into +eight copper moulds, which are two palms and three digits in diameter; +these are first smeared with a lute wash so that the cakes of +silver-lead may more easily fall out when they are turned over. If the +supply of moulds fails because the silver-lead flows down too rapidly +into the receiving-pit, then water is poured on them, in order that the +cakes may cool and be taken out of them more rapidly; thus the same +moulds may be used again immediately; if no such necessity urges the +refiner, he washes over the empty moulds with a lute wash. The ladle is +exactly similar to that which is used in pouring out the metals that are +melted in the blast furnace. When all the silver-lead has run down from +the passage into the receiving-pit, and has been poured out into copper +moulds, the thorns are drawn out of the passage into the receiving-pit +with a rabble; afterward they are raked on to the ground from the +receiving-pit, thrown with a shovel into a wheelbarrow, and, having been +conveyed away to a heap, are melted once again. The blade of the rabble +is two palms and as many digits long, two palms and a digit wide, and +joined to its back is an iron handle three feet long; into the iron +handle is inserted a wooden one as many feet in length. + +The residue cakes, after the silver-lead has been liquated from the +copper, are called "exhausted liquation cakes" (_fathiscentes_), because +when thus smelted they appear to be dried up. By placing a crowbar under +the cakes they are raised up, seized with tongs, and placed in the +wheelbarrow; they are then conveyed away to the furnace in which they +are "dried." The crowbar is somewhat similar to those generally used to +chip off the accretions that adhere to the walls of the blast furnace. +The tongs are two and a half feet long. With the same crowbar the +stalactites are chipped off from the copper plates from which they hang, +and with the same instrument the iron blocks are struck off the +exhausted liquation cakes to which they adhere. The refiner has +performed his day's task when he has liquated the silver-lead from +sixteen of the large cakes and twenty of the smaller ones; if he +liquates more than this, he is paid separately for it at the price for +extraordinary work. + +Silver, or lead mixed with silver, which we call _stannum_, is separated +by the above method from copper. This silver-lead is carried to the +cupellation furnace, in which lead is separated from silver; of these +methods I will mention only one, because in the previous book I have +explained them in detail. Amongst us some years ago only forty-four +_centumpondia_ of silver-lead and one of copper were melted together in +the cupellation furnaces, but now they melt forty-six _centumpondia_ of +silver-lead and one and a half _centumpondia_ of copper; in other +places, usually a hundred and twenty _centumpondia_ of silver-lead alloy +and six of copper are melted, in which manner they make about one +hundred and ten _centumpondia_ more or less of litharge and thirty of +hearth-lead. But in all these methods the silver which is in the copper +is mixed with the remainder of silver; the copper itself, equally with +the lead, will be changed partly into litharge and partly into +hearth-lead.[19] The silver-lead alloy which does not melt is taken from +the margin of the crucible with a hooked bar. + +[Illustration 522 (Exhausted Liquation Cakes): A--Cakes. B--Hammer.] + +The work of "drying" is distributed into four operations, which are +performed in four days. On the first--as likewise on the other three +days--the master begins at the fourth hour of the morning, and with his +assistant chips off the stalactites from the exhausted liquation cakes. +They then carry the cakes to the furnace, and put the stalactites upon +the heap of liquation thorns. The head of the chipping hammer is three +palms and as many digits long; its sharp edge is a palm wide; the round +end is three digits thick; the wooden handle is four feet long. + +The master throws pulverised earth into a small vessel, sprinkles water +over it, and mixes it; this he pours over the whole hearth, and +sprinkles charcoal dust over it to the thickness of a digit. If he +should neglect this, the copper, settling in the passages, would adhere +to the copper bed-plates, from which it can be chipped off only with +difficulty; or else it would adhere to the bricks, if the hearth was +covered with them, and when the copper is chipped off these they are +easily broken. On the second day, at the same time, the master arranges +bricks in ten rows; in this manner twelve passages are made. The first +two rows of bricks are between the first and the second openings on the +right of the furnace; the next three rows are between the second and +third openings, the following three rows are between the third and the +fourth openings, and the last two rows between the fourth and fifth +openings. These bricks are a foot and a palm long, two palms and a digit +wide, and a palm and two digits thick; there are seven of these thick +bricks in a row, so there are seventy all together. Then on the first +three rows of bricks they lay exhausted liquation cakes and a layer five +digits thick of large charcoal; then in a similar way more exhausted +liquation cakes are laid upon the other bricks, and charcoal is thrown +upon them; in this manner seventy _centumpondia_ of cakes are put on the +hearth of the furnace. But if half of this weight, or a little more, is +to be "dried," then four rows of bricks will suffice. Those who dry +exhausted liquation cakes[20] made from copper "bottoms" place ninety or +a hundred _centumpondia_[21] into the furnace at the same time. A place +is left in the front part of the furnace for the topmost cakes removed +from the forehearth in which copper is made, these being more suitable +for supporting the exhausted liquation cakes than are iron plates; +indeed, if the former cakes drip copper from the heat, this can be taken +back with the liquation thorns to the first furnace, but melted iron is +of no use to us in these matters. When the cakes of this kind have been +placed in front of the exhausted liquation cakes, the workman inserts +the iron bar into the holes on the inside of the wall, which are at a +height of three palms and two digits above the hearth; the hole to the +left penetrates through into the wall, so that the bar may be pushed +back and forth. This bar is round, eight feet long and two digits in +diameter; on the right side it has a haft made of iron, which is about a +foot from the right end; the aperture in this haft is a palm wide, two +digits high, and a digit thick. The bar holds the exhausted liquation +cakes opposite, lest they should fall down. When the operation of +"drying" is completed, a workman draws out this bar with a crook which +he inserts into the haft, as I will explain hereafter. + +[Illustration 525 (Drying Furnace for Liquation): A--Side walls. +B--Front arch. C--Rear arch. D--Wall in the rear arch. E--Inner wall. +F--Vent holes. G--Chimney. H--Hearth. I--Tank. K--Pipe. L--Plug. M--Iron +door. N--Transverse bars. O--Upright bars. P--Plates. Q--Rings of the +bars. R--Chains. S--Rows of bricks. T--Bar. V--Its haft. X--Copper +bed-plates.] + +In order that one should understand those things of which I have spoken, +and concerning which I am about to speak, it is necessary for me to give +some information beforehand about the furnace and how it is to be made. +It stands nine feet from the fourth long wall, and as far from the wall +which is between the second and fourth transverse walls. It consists of +walls, an arch, a chimney, an interior wall, and a hearth; the two walls +are at the sides; and they are eleven feet three palms and two digits +long, and where they support the chimney they are eight feet and a palm +high. At the front of the arch they are only seven feet high; they are +two feet three palms and two digits thick, and are made either of rock +or of bricks; the distance between them is eight feet, a palm and two +digits. There are two of the arches, for the space at the rear between +the walls is also arched from the ground, in order that it may be able +to support the chimney; the foundations of these arches are the walls of +the furnace; the span of the arch has the same length as the space +between the walls; the top of the arch is five feet, a palm and two +digits high. In the rear arch there is a wall made of bricks joined with +lime; this wall at a height of a foot and three palms from the ground +has five vent-holes, which are two palms and a digit high, a palm and a +digit wide, of which the first is near the right interior wall, and the +last near the left interior wall, the remaining three in the intervening +space; these vent-holes penetrate through the interior of the wall which +is in the arch. Half-bricks can be placed over the vent-holes, lest too +much air should be drawn into the furnace, and they can be taken out at +times, in order that he who is "drying" the exhausted liquation cakes +may inspect the passages, as they are called, to see whether the cakes +are being properly "dried." The front arch is three feet two palms +distant from the rear one; this arch is the same thickness as that of +the rear arch, but the span is six feet wide; the interior of the arch +itself is of the same height as the walls. A chimney is built upon the +arches and the walls, and is made of bricks joined together with lime; +it is thirty-six feet high and penetrates through the roof. The interior +wall is built against the rear arch and both the side walls, from which +it juts out a foot; it is three feet and the same number of palms high, +three palms thick, and is made of bricks joined together with lute and +smeared thickly with lute, sloping up to the height of a foot above it. +This wall is a kind of shield, for it protects the exterior walls from +the heat of the fire, which is apt to injure them; the latter cannot be +easily re-made, while the former can be repaired with little work. + +The hearth is made of lute, and is covered either with copper plates, +such as those of the furnaces in which silver is liquated from copper, +although they have no protuberances, or it may be covered with bricks, +if the owners are unwilling to incur the expense of copper plates. The +wider part of the hearth is made sloping in such a manner that the rear +end reaches as high as the five vent-holes, and the front end of the +hearth is so low that the back of the front arch is four feet, three +palms and as many digits above it, and the front five feet, three palms +and as many digits. The hearth beyond the furnaces is paved with bricks +for a distance of six feet. Near the furnace, against the fourth long +wall, is a tank thirteen feet and a palm long, four feet wide, and a +foot and three palms deep. It is lined on all sides with planks, lest +the earth should fall into it; on one side the water flows in through +pipes, and on the other, if the plug be pulled out, it soaks into the +earth; into this tank of water are thrown the cakes of copper from which +the silver and lead have been separated. The fore part of the front +furnace arch should be partly closed with an iron door; the bottom of +this door is six feet and two digits wide; the upper part is somewhat +rounded, and at the highest point, which is in the middle, it is three +feet and two palms high. It is made of iron bars, with plates fastened +to them with iron wire, there being seven bars--three transverse and +four upright--each of which is two digits wide and half a digit thick. +The lowest transverse bar is six feet and two palms long; the middle one +has the same length; the upper one is curved and higher at the centre, +and thus longer than the other two. The upright bars are two feet +distant from one another; both the outer ones are two feet and as many +palms high; but the centre ones are three feet and two palms. They +project from the upper curved transverse bar and have holes, in which +are inserted the hooks of small chains two feet long; the topmost links +of these chains are engaged in the ring of a third chain, which, when +extended, reaches to one end of a beam which is somewhat cut out. The +chain then turns around the beam, and again hanging down, the hook in +the other end is fastened in one of the links. This beam is eleven feet +long, a palm and two digits wide, a palm thick, and turns on an iron +axle fixed in a nearby timber; the rear end of the beam has an iron pin, +which is three palms and a digit long, and which penetrates through it +where it lies under a timber, and projects from it a palm and two digits +on one side, and three digits on the other side. At this point the pin +is perforated, in order that a ring may be fixed in it and hold it, +lest it should fall out of the beam; that end is hardly a digit thick, +while the other round end is thicker than a digit. When the door is to +be shut, this pin lies under the timber and holds the door so that it +cannot fall; the pin likewise prevents the rectangular iron band which +encircles the end of the beam, and into which is inserted the ring of a +long hook, from falling from the end. The lowest link of an iron chain, +which is six feet long, is inserted in the ring of a staple driven into +the right wall of the furnace, and fixed firmly by filling in with +molten lead. The hook suspended at the top from the ring should be +inserted in one of these lower links, when the door is to be raised; +when the door is to be let down, the hook is taken out of that link and +put into one of the upper links. + +[Illustration 527 (Drying Furnace for Liquation): A--The door let down. +B--Bar. C--Exhausted liquation cakes. D--Bricks. E--Tongs.] + +On the third day the master sets about the principal operation. First he +throws a basketful of charcoals on to the ground in front of the hearth, +and kindles them by adding live coals, and having thrown live coals on +to the cakes placed within, he spreads them equally all over with an +iron shovel. The blade of the shovel is three palms and a digit long, +and three palms wide; its iron handle is two palms long, and the wooden +one ten feet long, so that it can reach to the rear wall of the furnace. +The exhausted liquation cakes become incandescent in an hour and a half, +if the copper was good and hard, or after two hours, if it was soft and +fragile. The workman adds charcoal to them where he sees it is needed, +throwing it into the furnace through the openings on both sides between +the side walls and the closed door. This opening is a foot and a palm +wide. He lets down the door, and when the "slags" begin to flow he opens +the passages with a bar; this should take place after five hours; the +door is let down over the upper open part of the arch for two feet and +as many digits, so that the master can bear the violence of the heat. +When the cakes shrink, charcoal should not be added to them lest they +should melt. If the cakes made from poor and fragile copper are "dried" +with cakes made from good hard copper, very often the copper so settles +into the passages that a bar thrust into them cannot penetrate them. +This bar is of iron, six feet and two palms long, into which a wooden +handle five feet long is inserted. The refiner draws off the "slags" +with a rabble from the right side of the hearth. The blade of the rabble +is made of an iron plate a foot and a palm wide, gradually narrowing +toward the handle; the blade is two palms high, its iron handle is two +feet long, and the wooden handle set into it is ten feet long. + +[Illustration 528 (Drying Furnace for Liquation): A--The door raised. +B--Hooked bar. C--Two-pronged rake. D--Tongs. E--Tank.] + +When the exhausted liquation cakes have been "dried," the master raises +the door in the manner I have described, and with a long iron hook +inserted into the haft of the bar he draws it through the hole in the +left wall from the hole in the right wall; afterward he pushes it back +and replaces it. The master then takes out the exhausted liquation cakes +nearest to him with the iron hook; then he pulls out the cakes from the +bricks. This hook is two palms high, as many digits wide, and one thick; +its iron handle is two feet long, and the wooden handle eleven feet +long. There is also a two-pronged rake with which the "dried" cakes are +drawn over to the left side so that they may be seized with tongs; the +prongs of the rake are pointed, and are two palms long, as many digits +wide, and one digit thick; the iron part of the handle is a foot long, +the wooden part nine feet long. The "dried" cakes, taken out of the +hearth by the master and his assistants, are seized with other tongs and +thrown into the rectangular tank, which is almost filled with water. +These tongs are two feet and three palms long, both the handles are +round and more than a digit thick, and the ends are bent for a palm and +two digits; both the jaws are a digit and a half wide in front and +sharpened; at the back they are a digit thick, and then gradually taper, +and when closed, the interior is two palms and as many digits wide. + +The "dried" cakes which are dripping copper are not immediately dipped +into the tank, because, if so, they burst in fragments and give out a +sound like thunder. The cakes are afterward taken out of the tank with +the tongs, and laid upon the two transverse planks on which the workmen +stand; the sooner they are taken out the easier it is to chip off the +copper that has become ash-coloured. Finally, the master, with a spade, +raises up the bricks a little from the hearth, while they are still +warm. The blade of the spade is a palm and two digits long, the lower +edge is sharp, and is a palm and a digit wide, the upper end a palm +wide; its handle is round, the iron part being two feet long, and the +wooden part seven and a half feet long. + +On the fourth day the master draws out the liquation thorns which have +settled in the passages; they are much richer in silver than those that +are made when the silver-lead is liquated from copper in the liquation +furnace. The "dried" cakes drip but little copper, but nearly all their +remaining silver-lead and the thorns consist of it, for, indeed, in one +_centumpondium_ of "dried" copper there should remain only half an +_uncia_ of silver, and there sometimes remain only three _drachmae_.[22] +Some smelters chip off the metal adhering to the bricks with a hammer, +in order that it may be melted again; others, however, crush the bricks +under the stamps and wash them, and the copper and lead thus collected +is melted again. The master, when he has taken these things away and put +them in their places, has finished his day's work. + +[Illustration 530 (Dried Liquation Cakes): A--Tank. B--Board. C--Tongs. +D--"Dried" cakes taken out of the tanks. E--Block. F--Rounded hammer. +G--Pointed hammer.] + +The assistants take the "dried" cakes out of the tank on the next day, +place them on an oak block, and first pound them with rounded hammers in +order that the ash-coloured copper may fall away from them, and then +they dig out with pointed picks the holes in the cakes, which contain +the same kind of copper. The head of the round hammer is three palms and +a digit long; one end of the head is round and two digits long and +thick; the other end is chisel-shaped, and is two digits and a half +long. The sharp pointed hammer is the same length as the round hammer, +but one end is pointed, the other end is square, and gradually tapers to +a point. + +The nature of copper is such that when it is "dried" it becomes ash +coloured, and since this copper contains silver, it is smelted again in +the blast furnaces.[23] + +[Illustration 532 (Copper Refining Furnace): A--Hearth of the furnace. +B--Chimney. C--Common pillar. D--Other pillars. The partition wall is +behind the common pillar and not to be seen. E--Arches. F--Little walls +which protect the partition wall from injury by the fire. G--Crucibles. +H--Second long wall. I--Door. K--Spatula. L--The other spatula. M--The +broom in which is inserted a stick. N--Pestles. O--Wooden mallet. +P--Plate. Q--Stones. R--Iron rod.] + +I have described sufficiently the method by which exhausted liquation +cakes are "dried"; now I will speak of the method by which they are made +into copper after they have been "dried." These cakes, in order that +they may recover the appearance of copper which they have to some extent +lost, are melted in four furnaces, which are placed against the second +long wall in the part of the building between the second and third +transverse walls. This space is sixty-three feet and two palms long, and +since each of these furnaces occupies thirteen feet, the space which is +on the right side of the first furnace, and on the left of the fourth, +are each three feet and three palms wide, and the distance between the +second and third furnace is six feet. In the middle of each of these +three spaces is a door, a foot and a half wide and six feet high, and +the middle one is common to the master of each of the furnaces. Each +furnace has its own chimney, which rises between the two long walls +mentioned above, and is supported by two arches and a partition wall. +The partition wall is between the two furnaces, and is five feet long, +ten feet high, and two feet thick; in front of it is a pillar belonging +in common to the front arches of the furnace on either side, which is +two feet and as many palms thick, three feet and a half wide. The front +arch reaches from this common pillar to another pillar that is common to +the side arch of the same furnace; this arch on the right spans from the +second long wall to the same pillar, which is two feet and as many palms +wide and thick at the bottom. The interior of the front arch is nine +feet and a palm wide, and eight feet high at its highest point; the +interior of the arch which is on the right side, is five feet and a palm +wide, and of equal height to the other, and both the arches are built of +the same height as the partition wall. Imposed upon these arches and the +partition wall are the walls of the chimney; these slope upward, and +thus contract, so that at the upper part, where the fumes are emitted, +the opening is eight feet in length, one foot and three palms in width. +The fourth wall of the chimney is built vertically upon the second long +wall. As the partition wall is common to the two furnaces, so its +superstructure is common to the two chimneys. In this sensible manner +the chimney is built. At the front each furnace is six feet two palms +long, and three feet two palms wide, and a cubit high; the back of each +furnace is against the second long wall, the front being open. The first +furnace is open and sloping at the right side, so that the slags may be +drawn out; the left side is against the partition wall, and has a little +wall built of bricks cemented together with lute; this little wall +protects the partition wall from injury by the fire. On the contrary, +the second furnace has the left side open and the right side is against +the partition wall, where also it has its own little wall which protects +the partition wall from the fire. The front of each furnace is built of +rectangular rocks; the interior of it is filled up with earth. Then in +each of the furnaces at the rear, against the second long wall, is an +aperture through an arch at the back, and in these are fixed the copper +pipes. Each furnace has a round pit, two feet and as many palms wide, +built three feet away from the partition wall. Finally, under the pit of +the furnace, at a depth of a cubit, is the hidden receptacle for +moisture, similar to the others, whose vent penetrates through the +second long wall and slopes upward to the right from the first furnace, +and to the left from the second. If copper is to be made the next day, +then the master cuts out the crucible with a spatula, the blade of which +is three digits wide and as many palms long, the iron handle being two +feet long and one and a half digits in diameter; the wooden handle +inserted into it is round, five feet long and two digits in diameter. +Then, with another cutting spatula, he makes the crucible smooth; the +blade of this spatula is a palm wide and two palms long; its handle, +partly of iron, partly of wood, is similar in every respect to the first +one. Afterward he throws pulverised clay and charcoal into the crucible, +pours water over it, and sweeps it over with a broom into which a stick +is fixed. Then immediately he throws into the crucible a powder, made of +two wheelbarrowsful of sifted charcoal dust, as many wheelbarrowsful of +pulverised clay likewise sifted, and six basketsful of river sand which +has passed through a very fine sieve. This powder, like that used by +smelters, is sprinkled with water and moistened before it is put into +the crucible, so that it may be fashioned by the hands into shapes +similar to snowballs. When it has been put in, the master first kneads +it and makes it smooth with his hands, and then pounds it with two +wooden pestles, each of which is a cubit long; each pestle has a round +head at each end, but one of these is a palm in diameter, the other +three digits; both are thinner in the middle, so that they may be held +in the hand. Then he again throws moistened powder into the crucible, +and again makes it smooth with his hands, and kneads it with his fists +and with the pestles; then, pushing upward and pressing with his +fingers, he makes the edge of the crucible smooth. After the crucible +has been made smooth, he sprinkles in dry charcoal dust, and again +pounds it with the same pestles, at first with the narrow heads, and +afterward with the wider ones. Then he pounds the crucible with a wooden +mallet two feet long, both heads of which are round and three digits in +diameter; its wooden handle is two palms long, and one and a half digits +in diameter. Finally, he throws into the crucible as much pure sifted +ashes as both hands can hold, and pours water into it, and, taking an +old linen rag, he smears the crucible over with the wet ashes. The +crucible is round and sloping. If copper is to be made from the best +quality of "dried" cakes, it is made two feet wide and one deep, but if +from other cakes, it is made a cubit wide and two palms deep. The master +also has an iron band curved at both ends, two palms long and as many +digits wide, and with this he cuts off the edges of the crucible if they +are higher than is necessary. The copper pipe is inclined, and projects +three digits from the wall, and has its upper end and both sides smeared +thick with lute, that it may not be burned; but the underside of the +pipe is smeared thinly with lute, for this side reaches almost to the +edge of the crucible, and when the crucible is full the molten copper +touches it. The wall above the pipe is smeared over with lute, lest that +should be damaged. He does the same to the other side of an iron plate, +which is a foot and three palms long and a foot high; this stands on +stones near the crucible at the side where the hearth slopes, in order +that the slag may run out under it. Others do not place the plates upon +stones, but cut out of the plate underneath a small piece, three digits +long and three digits wide; lest the plate should fall, it is supported +by an iron rod fixed in the wall at a height of two palms and the same +number of digits, and it projects from the wall three palms. + +Then with an iron shovel, whose wooden handle is six feet long, he +throws live charcoal into the crucible; or else charcoal, kindled by +means of a few live coals, is added to them. Over the live charcoal he +lays "dried" cakes, which, if they were of copper of the first quality, +weigh all together three _centumpondia_, or three and a half +_centumpondia_; but if they were of copper of the second quality, then +two and a half _centumpondia_; if they were of the third quality, then +two _centumpondia_ only; but if they were of copper of very superior +quality, then they place upon it six _centumpondia_, and in this case +they make the crucible wider and deeper.[24] The lowest "dried" cake is +placed at a distance of two palms from the pipe, the rest at a greater +distance, and when the lower ones are melted the upper ones fall down +and get nearer to the pipe; if they do not fall down they must be pushed +with a shovel. The blade of the shovel is a foot long, three palms and +two digits wide, the iron part of the handle is two palms long, the +wooden part nine feet. Round about the "dried" cakes are placed large +long pieces of charcoal, and in the pipe are placed medium-sized pieces. +When all these things have been arranged in this manner, the fire must +be more violently excited by the blast from the bellows. When the copper +is melting and the coals blaze, the master pushes an iron bar into the +middle of them in order that they may receive the air, and that the +flame can force its way out. This pointed bar is two and a half feet +long, and its wooden handle four feet long. When the cakes are partly +melted, the master, passing out through the door, inspects the crucible +through the bronze pipe, and if he should find that too much of the +"slag" is adhering to the mouth of the pipe, and thus impeding the blast +of the bellows, he inserts the hooked iron bar into the pipe through the +nozzle of the bellows, and, turning this about the mouth of the pipe, he +removes the "slags" from it. The hook on this bar is two digits high; +the iron part of the handle is three feet long; the wooden part is the +same number of palms long. Now it is time to insert the bar under the +iron plate, in order that the "slags" may flow out. When the cakes, +being all melted, have run into the crucible, he takes out a sample of +copper with the third round bar, which is made wholly of iron, and is +three feet long, a digit thick, and has a steel point lest its pores +should absorb the copper. When he has compressed the bellows, he +introduces this bar as quickly as possible into the crucible through the +pipe between the two nozzles, and takes out samples two, three, or four +times, until he finds that the copper is perfectly refined. If the +copper is good it adheres easily to the bar, and two samples suffice; if +it is not good, then many are required. It is necessary to smelt it in +the crucible until the copper adhering to the bar is seen to be of a +brassy colour, and if the upper as well as the lower part of the thin +layer of copper may be easily broken, it signifies that the copper is +perfectly melted; he places the point of the bar on a small iron anvil, +and chips off the thin layer of copper from it with a hammer.[25] + +[Illustration 534 (Copper Refining): A--Pointed bar. B--Thin copper +layer. C--Anvil. D--Hammer.] + +[Illustration 537 (Copper Refining): A--Crucible. B--Board. +C--Wedge-shaped bar. D--Cakes of copper made by separating them with the +wedge-shaped bar. E--Tongs. F--Tub.] + +If the copper is not good, the master draws off the "slags" twice, or +three times if necessary--the first time when some of the cakes have +been melted, the second when all have melted, the third time when the +copper has been heated for some time. If the copper was of good quality, +the "slags" are not drawn off before the operation is finished, but at +the time they are to be drawn off, he depresses the bar over both +bellows, and places over both a stick, a cubit long and a palm wide, +half cut away at the upper part, so that it may pass under the iron pin +fixed at the back in the perforated wood. This he does likewise when the +copper has been completely melted. Then the assistant removes the iron +plate with the tongs; these tongs are four feet three palms long, their +jaws are about a foot in length, and their straight part measures two +palms and three digits, and the curved a palm and a digit. The same +assistant, with the iron shovel, throws and heaps up the larger pieces +of charcoal into that part of the hearth which is against the little +wall which protects the other wall from injury by fire, and partly +extinguishes them by pouring water over them. The master, with a hazel +stick inserted into the crucible, stirs it twice. Afterward he draws +off the slags with a rabble, which consists of an iron blade, wide and +sharp, and of alder-wood; the blade is a digit and a half in width and +three feet long; the wooden handle inserted in its hollow part is the +same number of feet long, and the alder-wood in which the blade is fixed +must have the figure of a rhombus; it must be three palms and a digit +long, a palm and two digits wide, and a palm thick. Subsequently he +takes a broom and sweeps the charcoal dust and small coal over the whole +of the crucible, lest the copper should cool before it flows together; +then, with a third rabble, he cuts off the slags which may adhere to the +edge of the crucible. The blade of this rabble is two palms long and a +palm and one digit wide, the iron part of the handle is a foot and three +palms long, the wooden part six feet. Afterward he again draws off the +slags from the crucible, which the assistant does not quench by pouring +water upon them, as the other slags are usually quenched, but he +sprinkles over them a little water and allows them to cool. If the +copper should bubble, he presses down the bubbles with the rabble. Then +he pours water on the wall and the pipes, that it may flow down warm +into the crucible, for, the copper, if cold water were to be poured over +it while still hot, would spatter about. If a stone, or a piece of lute +or wood, or a damp coal should then fall into it, the crucible would +vomit out all the copper with a loud noise like thunder, and whatever it +touches it injures and sets on fire. Subsequently he lays a curved board +with a notch in it over the front part of the crucible; it is two feet +long, a palm and two digits wide, and a digit thick. Then the copper in +the crucible should be divided into cakes with an iron wedge-shaped bar; +this is three feet long, two digits wide, and steeled on the end for the +distance of two digits, and its wooden handle is three feet long. He +places this bar on the notched board, and, driving it into the copper, +moves it forward and back, and by this means the water flows into the +vacant space in the copper, and he separates the cake from the rest of +the mass. If the copper is not perfectly smelted the cakes will be too +thick, and cannot be taken out of the crucible easily. Each cake is +afterward seized by the assistant with the tongs and plunged into the +water in the tub; the first one is placed aside so that the master may +re-melt it again immediately, for, since some "slags" adhere to it, it +is not as perfect as the subsequent ones; indeed, if the copper is not +of good quality, he places the first two cakes aside. Then, again +pouring water over the wall and the pipes, he separates out the second +cake, which the assistant likewise immerses in water and places on the +ground together with the others separated out in the same way, which he +piles upon them. These, if the copper was of good quality, should be +thirteen or more in number; if it was not of good quality, then fewer. +If the copper was of good quality, this part of the operation, which +indeed is distributed into four parts, is accomplished by the master in +two hours; if of mediocre quality, in two and a half hours; if of bad +quality, in three. The "dried" cakes are re-melted, first in the first +crucible and then in the second. The assistant must, as quickly as +possible, quench all the cakes with water, after they have been cut out +of the second crucible. Afterward with the tongs he replaces in its +proper place the iron plate which was in front of the furnace, and +throws the charcoal back into the crucible with a shovel. Meanwhile the +master, continuing his work, removes the wooden stick from the bars of +the bellows, so that in re-melting the other cakes he may accomplish the +third part of his process; this must be carefully done, for if a +particle from any iron implement should by chance fall into the +crucible, or should be thrown in by any malevolent person, the copper +could not be made until the iron had been consumed, and therefore double +labour would have to be expended upon it. Finally, the assistant +extinguishes all the glowing coals, and chips off the dry lute from the +mouth of the copper pipe with a hammer; one end of this hammer is +pointed, the other round, and it has a wooden handle five feet long. +Because there is danger that the copper would be scattered if the +_pompholyx_ and _spodos_, which adhere to the walls and the hood erected +upon them, should fall into the crucible, he cleans them off in the +meantime. Every week he takes the copper flowers out of the tub, after +having poured off the water, for these fall into it from the cakes when +they are quenched.[26] + +The bellows which this master uses differ in size from the others, for +the boards are seven and a half feet long; the back part is three feet +wide; the front, where the head is joined on is a foot, two palms and as +many digits. The head is a cubit and a digit long; the back part of it +is a cubit and a palm wide, and then becomes gradually narrower. The +nozzles of the bellows are bound together by means of an iron chain, +controlled by a thick bar, one end of which penetrates into the ground +against the back of the long wall, and the other end passes under the +beam which is laid upon the foremost perforated beams. These nozzles are +so placed in a copper pipe that they are at a distance of a palm from +the mouth; the mouth should be made three digits in diameter, that the +air may be violently expelled through this narrow aperture. + +There now remain the liquation thorns, the ash-coloured copper, the +"slags," and the _cadmia_.[27] Liquation cakes are made from thorns in +the following manner.[28] There are taken three-quarters of a +_centumpondium_ of thorns, which have their origin from the cakes of +copper-lead alloy when lead-silver is liquated, and as many parts of a +_centumpondium_ of the thorns derived from cakes made from once +re-melted thorns by the same method, and to them are added a +_centumpondium_ of de-silverized lead and half a _centumpondium_ of +hearth-lead. If there is in the works plenty of litharge, it is +substituted for the de-silverized lead. One and a half _centumpondia_ of +litharge and hearth-lead is added to the same weight of primary thorns, +and half a _centumpondium_ of thorns which have their origin from +liquation cakes composed of thorns twice re-melted by the same method +(tertiary thorns), and a fourth part of a _centumpondium_ of thorns +which are produced when the exhausted liquation cakes are "dried." By +both methods one single liquation cake is made from three +_centumpondia_. In this manner the smelter makes every day fifteen +liquation cakes, more or less; he takes great care that the metallic +substances, from which the first liquation cake is made, flow down +properly and in due order into the forehearth, before the material of +which the subsequent cake is to be made. Five of these liquation cakes +are put simultaneously into the furnace in which silver-lead is liquated +from copper, they weigh almost fourteen _centumpondia_, and the "slags" +made therefrom usually weigh quite a _centumpondium_. In all the +liquation cakes together there is usually one _libra_ and nearly two +_unciae_ of silver, and in the silver-lead which drips from those cakes, +and weighs seven and a half _centumpondia_, there is in each an _uncia_ +and a half of silver. In each of the three _centumpondia_ of liquation +thorns there is almost an _uncia_ of silver, and in the two +_centumpondia_ and a quarter of exhausted liquation cakes there is +altogether one and a half _unciae_; yet this varies greatly for each +variety of thorns, for in the thorns produced from primary liquation +cakes made of copper and lead when silver-lead is liquated from the +copper, and those produced in "drying" the exhausted liquation cakes, +there are almost two _unciae_ of silver; in the others not quite an +_uncia_. There are other thorns besides, of which I will speak a little +further on. + +Those in the Carpathian Mountains who make liquation cakes from the +copper "bottoms" which remain after the upper part of the copper is +divided from the lower, in the furnace similar to an oven, produce +thorns when the poor or mediocre silver-lead is liquated from the +copper. These, together with those made of cakes of re-melted thorns, or +made with re-melted litharge, are placed in a heap by themselves; but +those that are made from cakes melted from hearth-lead are placed in a +heap separate from the first, and likewise those produced from "drying" +the exhausted liquation cakes are placed separately; from these thorns +liquation cakes are made. From the first heap they take the fourth part +of a _centumpondium_, from the second the same amount, from the third a +_centumpondium_,--to which thorns are added one and a half +_centumpondia_ of litharge and half a _centumpondium_ of hearth-lead, +and from these, melted in the blast furnace, a liquation cake is made; +each workman makes twenty such cakes every day. But of theirs enough has +been said for the present; I will return to ours. + +The ash-coloured copper[29] which is chipped off, as I have stated, from +the "dried" cakes, used some years ago to be mixed with the thorns +produced from liquation of the copper-lead alloy, and contained in +themselves, equally with the first, two _unciae_ of silver; but now it +is mixed with the concentrates washed from the accretions and the other +material. The inhabitants of the Carpathian Mountains melt this kind of +copper in furnaces in which are re-melted the "slags" which flow out +when the copper is refined; but as this soon melts and flows down out of +the furnace, two workmen are required for the work of smelting, one of +whom smelts, while the other takes out the thick cakes from the +forehearth. These cakes are only "dried," and from the "dried" cakes +copper is again made. + +The "slags"[30] are melted continually day and night, whether they have +been drawn off from the alloyed metals with a rabble, or whether they +adhered to the forehearth to the thickness of a digit and made it +smaller and were taken off with spatulas. In this manner two or three +liquation cakes are made, and afterward much or little of the "slag," +skimmed from the molten alloy of copper and lead, is re-melted. Such +liquation cakes should weigh up to three _centumpondia_, in each of +which there is half an _uncia_ of silver. Five cakes are placed at the +same time in the furnace in which argentiferous lead is liquated from +copper, and from these are made lead which contains half an _uncia_ of +silver to the _centumpondium_. The exhausted liquation cakes are laid +upon the other baser exhausted liquation cakes, from both of which +yellow copper is made. The base thorns thus obtained are re-melted with +a few baser "slags," after having been sprinkled with concentrates from +furnace accretions and other material, and in this manner six or seven +liquation cakes are made, each of which weighs some two _centumpondia_. +Five of these are placed at the same time in the furnace in which +silver-lead is liquated from copper; these drip three _centumpondia_ of +lead, each of which contains half an _uncia_ of silver. The basest +thorns thus produced should be re-melted with only a little "slag." The +copper alloyed with lead, which flows down from the furnace into the +forehearth, is poured out with a ladle into oblong copper moulds; these +cakes are "dried" with base exhausted liquation cakes. The thorns they +produce are added to the base thorns, and they are made into cakes +according to the method I have described. From the "dried" cakes they +make copper, of which some add a small portion to the best "dried" cakes +when copper is made from them, in order that by mixing the base copper +with the good it may be sold without loss. The "slags," if they are +utilisable, are re-melted a second and a third time, the cakes made from +them are "dried," and from the "dried" cakes is made copper, which is +mixed with the good copper. The "slags," drawn off by the master who +makes copper out of "dried" cakes, are sifted, and those which fall +through the sieve into a vessel placed underneath are washed; those +which remain in it are emptied into a wheelbarrow and wheeled away to +the blast furnaces, and they are re-melted together with other "slags," +over which are sprinkled the concentrates from washing the slags or +furnace accretions made at this time. The copper which flows out of the +furnace into the forehearth, is likewise dipped out with a ladle into +oblong copper moulds; in this way nine or ten cakes are made, which are +"dried," together with bad exhausted liquation cakes, and from these +"dried" cakes yellow[31] copper is made. + +[Illustration 543 (Copper Refining): A--Furnace. B--Forehearth. +C--Oblong moulds.] + +The _cadmia_,[32] as it is called by us, is made from the "slags" which +the master, who makes copper from "dried" cakes, draws off together with +other re-melted base "slags"; for, indeed, if the copper cakes made from +such "slags" are broken, the fragments are called _cadmia_; from this +and yellow copper is made _caldarium_ copper in two ways. For either two +parts of _cadmia_ are mixed with one of yellow copper in the blast +furnaces, and melted; or, on the contrary, two parts of yellow copper +with one of _cadmia_, so that the _cadmia_ and yellow copper may be well +mixed; and the copper which flows down from the furnace into the +forehearth is poured out with a ladle into oblong copper moulds heated +beforehand. These moulds are sprinkled over with charcoal dust before +the _caldarium_ copper is to be poured into them, and the same dust is +sprinkled over the copper when it is poured in, lest the _cadmia_ and +yellow copper should freeze before they have become well mixed. With a +piece of wood the assistant cleanses each cake from the dust, when it is +turned out of the mould. Then he throws it into the tub containing hot +water, for the _caldarium_ copper is finer if quenched in hot water. But +as I have so often made mention of the oblong copper moulds, I must now +speak of them a little; they are a foot and a palm long, the inside is +three palms and a digit wide at the top, and they are rounded at the +bottom. + +The concentrates are of two kinds--precious and base.[33] The first are +obtained from the accretions of the blast furnace, when liquation cakes +are made from copper and lead, or from precious liquation thorns, or +from the better quality "slags," or from the best grade of concentrates, +or from the sweepings and bricks of the furnaces in which exhausted +liquation cakes are "dried"; all of these things are crushed and washed, +as I explained in Book VIII. The base concentrates are made from +accretions formed when cakes are cast from base thorns or from the worst +quality of slags. The smelter who makes liquation cakes from the +precious concentrates, adds to them three wheelbarrowsful of litharge +and four barrowsful of hearth-lead and one of ash-coloured copper, from +all of which nine or ten liquation cakes are melted out, of which five +at a time are placed in the furnace in which silver-lead is liquated +from copper; a _centumpondium_ of the lead which drips from these cakes +contains one _uncia_ of silver. The liquation thorns are placed apart +by themselves, of which one basketful is mixed with the precious thorns +to be re-melted. The exhausted liquation cakes are "dried" at the same +time as other good exhausted liquation cakes. + +The thorns which are drawn off from the lead, when it is separated from +silver in the cupellation furnace[34], and the hearth-lead which remains +in the crucible in the middle part of the furnaces, together with the +hearth material which has become defective and has absorbed silver-lead, +are all melted together with a little slag in the blast furnaces. The +lead, or rather the silver-lead, which flows from the furnace into the +forehearth, is poured out into copper moulds such as are used by the +refiners; a _centumpondium_ of such lead contains four _unciae_ of +silver, or, if the hearth was defective, it contains more. A small +portion of this material is added to the copper and lead when liquation +cakes are made from them, if more were to be added the alloy would be +much richer than it should be, for which reason the wise foreman of the +works mixes these thorns with other precious thorns. The hearth-lead +which remains in the middle of the crucible, and the hearth material +which absorbs silver-lead, is mixed with other hearth-lead which remains +in the cupellation furnace crucible; and yet some cakes, made rich in +this manner, may be placed again in the cupellation furnaces, together +with the rest of the silver-lead cakes which the refiner has made. + +The inhabitants of the Carpathian Mountains, if they have an abundance +of finely crushed copper[35] or lead either made from "slags," or +collected from the furnace in which the exhausted liquation cakes are +dried, or litharge, alloy them in various ways. The "first" alloy +consists of two _centumpondia_ of lead melted out of thorns, litharge, +and thorns made from hearth-lead, and of half a _centumpondium_ each of +lead collected in the furnace in which exhausted liquation cakes are +"dried," and of copper _minutum_, and from these are made liquation +cakes; the task of the smelter is finished when he has made forty +liquation cakes of this kind. The "second" alloy consists of two +_centumpondia_ of litharge, of one and a quarter _centumpondia_ of +de-silverized lead or lead from "slags," and of half a _centumpondium_ +of lead made from thorns, and of as much copper _minutum_. The "third" +alloy consists of three _centumpondia_ of litharge and of half a +_centumpondium_ each of de-silverized lead, of lead made from thorns, +and of copper _minutum contusum_. Liquation cakes are made from all +these alloys; the task of the smelters is finished when they have made +thirty cakes. + +The process by which cakes are made among the Tyrolese, from which they +separate the silver-lead, I have explained in Book IX. + +Silver is separated from iron in the following manner. Equal portions of +iron scales and filings and of _stibium_ are thrown into an earthenware +crucible which, when covered with a lid and sealed, is placed in a +furnace, into which air is blown. When this has melted and again cooled, +the crucible is broken; the button that settles in the bottom of it, +when taken out, is pounded to powder, and the same weight of lead being +added, is mixed and melted in a second crucible; at last this button is +placed in a cupel and the lead is separated from the silver.[36] + +There are a great variety of methods by which one metal is separated +from other metals, and the manner in which the same are alloyed I have +explained partly in the eighth book of _De Natura Fossilium_, and partly +I will explain elsewhere. Now I will proceed to the remainder of my +subject. + + END OF BOOK XI. + + +FOOTNOTES: + +[1] The whole of this Book is devoted to the subject of the separation +of silver from copper by liquation, except pages 530-9 on copper +refining, and page 544 on the separation of silver from iron. We believe +a brief outline of the liquation process here will refresh the mind of +the reader, and enable him to peruse the Book with more satisfaction. +The fundamental principle of the process is that if a copper-lead alloy, +containing a large excess of lead, be heated in a reducing atmosphere, +above the melting point of lead but below that of copper, the lead will +liquate out and carry with it a large proportion of the silver. As the +results are imperfect, the process cannot be carried through in one +operation, and a large amount of bye-products is created which must be +worked up subsequently. The process, as here described, falls into six +stages. 1st, Melting the copper and lead in a blast furnace to form +"liquation cakes"--that is, the "leading." If the copper contain too +little silver to warrant liquation directly, then the copper is +previously enriched by melting and drawing off from a settling pot the +less argentiferous "tops" from the metal, liquation cakes being made +from the enriched "bottoms." 2nd, Liquation of the argentiferous lead +from the copper. This work was carried out in a special furnace, to +which the admission of air was prevented as much as possible in order to +prevent oxidation. 3rd, "Drying" the residual copper, which retained +some lead, in a furnace with a free admission of air. The temperature +was raised to a higher degree than in the liquation furnace, and the +expelled lead was oxidized. 4th, Cupellation of the argentiferous lead. +5th, Refining of the residual copper from the "drying" furnace by +oxidation of impurities and poling in a "refining furnace." 6th, +Re-alloy and re-liquation of the bye-products. These consist of: _a_, +"slags" from "leading"; _b_, "slags" from "drying"; _c_, "slags" from +refining of the copper. All of these "slags" were mainly lead oxides, +containing some cuprous oxides and silica from the furnace linings; _d_, +"thorns" from liquation; _e_, "thorns" from "drying"; _f_, "thorns" from +skimmings during cupellation; these were again largely lead oxides, but +contained rather more copper and less silica than the "slags"; _g_, +"ash-coloured copper," being scales from the "dried" copper, were +cuprous oxides, containing considerable lead oxides; _h_, concentrates +from furnace accretions, crushed bricks, &c. + +The discussion of detailed features of the process has been reserved to +notes attached to the actual text, to which the reader is referred. As +to the general result of liquation, Karsten (see below) estimates the +losses in the liquation of the equivalent of 100 lbs. of argentiferous +copper to amount to 32-35 lbs. of lead and 5 to 6 lbs. of copper. Percy +(see below) quotes results at Lautenthal in the Upper Harz for the years +1857-60, showing losses of 25% of the silver, 9.1% of the copper, and +36.37 lbs. of lead to the 100 lbs. of copper, or say, 16% of the lead; +and a cost of £8 6s. per ton of copper. The theoretical considerations +involved in liquation have not been satisfactorily determined. Those who +may wish to pursue the subject will find repeated descriptions and much +discussion in the following works, which have been freely consulted in +the notes which follow upon particular features of the process. It may +be mentioned that Agricola's treatment of the subject is more able than +any down to the 18th century. Ercker (_Beschreibung Allerfürnemsten +Mineralischen_, etc., Prague, 1574). Lohneys (_Bericht vom Bergwercken_, +etc., Zellerfeldt, 1617). Schlüter (_Gründlicher Unterricht von +Hütte-Werken_, Braunschweig, 1738). _Karsten_ (_System der Metallurgie +V._ and _Archiv für Bergbau und Hüttenwesen_, 1st series, 1825). +Berthier (_Annales des Mines_, 1825, II.). Percy (Metallurgy of Silver +and Gold, London, 1880). + +NOMENCLATURE.--This process held a very prominent position in German +metallurgy for over four centuries, and came to have a well-defined +nomenclature of its own, which has never found complete equivalents in +English, our metallurgical writers to the present day adopting more or +less of the German terms. Agricola apparently found no little difficulty +in adapting Latin words to his purpose, but stubbornly adhered to his +practice of using no German at the expense of long explanatory clauses. +The following table, prepared for convenience in translation, is +reproduced. The German terms are spelled after the manner used in most +English metallurgies, some of them appear in Agricola's Glossary to _De +Re Metallica_. + + English. Latin. German. + + Blast furnace _Prima fornax_ _Schmeltzofen_ + + Liquation furnace _Fornax in qua argentum et _Saigernofen_ + plumbum ab aere secernuntur_ + + Drying furnace _Fornax in qua aerei panes _Darrofen_ + fathiscentes torrentur_ + + Refining hearth _Fornax in qua panes aerei _Gaarherd_ + torrefacti coquuntur_ + + Cupellation _Secunda fornax_, or _Treibherd_ + furnace _fornax in qua plumbum + ab argento separatur_ + + Leading _Mistura_ _Frischen_ + + Liquating _Stillare_, or _distillare_ _Saigern_ + + "Drying" _Torrere_ _Darren_ + + Refining _Aes ex panibus torrefactis _Gaarmachen_ + conficere_ + Liquation cakes _Panes ex aere ac plumbo misti_ _Saigerstock_ + + Exhausted _Panes fathiscentes_ _Kiehnstock_, + liquation cakes or _Kinstocke_ + + "Dried" cakes _Panes torrefacti_ _Darrlinge_ + + Slags from leading _Recrementa_ _Frischschlacke_ + (with explanatory phrases) + + Slags from drying _Recrementa_ _Darrost_ + (with explanatory phrases) + + Slags from refining _Recrementa_ _Gaarschlacke_ + (with explanatory phrases) + + Liquation thorns _Spinae_ _Saigerdörner_, + (with explanatory phrases) or _Röstdörner_ + + Thorns from "drying" _Spinae_ _Darrsöhle_ + (with explanatory phrases) + + Thorns from _Spinae_ _Abstrich_ + cupellation (with explanatory phrases) + + Silver-lead or _Stannum_ _Saigerwerk_ or + liquated _saigerblei_ + silver-lead + + Ash-coloured copper _Aes cinereum_ _Pickschiefer_ + or _schifer_ + + Furnace accretions _Cadmiae_ _Offenbrüche_ + or "accretions" + +HISTORICAL NOTE.--So far as we are aware, this is the first complete +discussion of this process, although it is briefly mentioned by one +writer before Agricola--that is, by Biringuccio (III, 5, 8), who wrote +ten years before this work was sent to the printer. His account is very +incomplete, for he describes only the bare liquation, and states that +the copper is re-melted with lead and re-liquated until the silver is +sufficiently abstracted. He neither mentions "drying" nor any of the +bye-products. In his directions the silver-lead alloy was cupelled and +the copper ultimately refined, obviously by oxidation and poling, +although he omits the pole. In A.D. 1150 Theophilus (p. 305, Hendrie's +Trans.) describes melting lead out of copper ore, which would be a form +of liquation so far as separation of these two metals is concerned, but +obviously not a process for separating silver from copper. This passage +is quoted in the note on copper smelting (Note on p. 405). A process of +such well-developed and complicated a character must have come from a +period long before Agricola; but further than such a surmise, there +appears little to be recorded. Liquation has been during the last fifty +years displaced by other methods, because it was not only tedious and +expensive, but the losses of metal were considerable. + +[2] _Paries_,--"Partition" or "wall." The author uses this term +throughout in distinction to _murus_, usually applying the latter to the +walls of the building and the former to furnace walls, chimney walls, +etc. In order to gain clarity, we have introduced the term "hood" in +distinction to "chimney," and so far as possible refer to the _paries_ +of these constructions and furnaces as "side of the furnace," "side of +the hood," etc. + +[4] From this point on, the construction of the roofs, in the absence of +illustration, is hopeless of intelligent translation. The constant +repetition of "_tignum_," "_tigillum_," "_trabs_," for at least fifteen +different construction members becomes most hopelessly involved, +especially as the author attempts to distinguish between them in a sort +of "House-that-Jack-built" arrangement of explanatory clauses. + +[5] In the original text this is given as the "fifth," a manifest +impossibility. + +[6] _Chelae_,--"claws." + +[7] If Roman weights, this would be 5.6 short tons, and 7.5 tons if +German _centner_ is meant. + +[8] This is, no doubt, a reference to Pliny's statement (XXXIII, 35) +regarding litharge at Puteoli. This passage from Pliny is given in the +footnote on p. 466. Puteoli was situated on the Bay of Naples. + +[9] By this expression is apparently meant the "bottoms" produced in +enriching copper, as described on p. 510. + +[10] The details of the preparation of liquation cakes--"leading"--were +matters of great concern to the old metallurgists. The size of the +cakes, the proportion of silver in the original copper and in the +liquated lead, the proportion of lead and silver left in the residual +cakes, all had to be reached by a series of compromises among militant +forces. The cakes were generally two and one-half to three and one-half +inches thick and about two feet in diameter, and weighed 225 to 375 lbs. +This size was wonderfully persistent from Agricola down to modern times; +and was, no doubt, based on sound experience. If the cakes were too +small, they required proportionately more fuel and labour; whilst if too +large, the copper began to melt before the maximum lead was liquated. +The ratio of the copper and lead was regulated by the necessity of +enough copper to leave a substantial sponge mass the shape of the +original cake, and not so large a proportion as to imprison the lead. +That is, if the copper be in too small proportion the cakes break down; +and if in too large, then insufficient lead liquates out, and the +extraction of silver decreases. Ercker (p. 106-9) insists on the +equivalent of about 3 copper to 9.5 lead; Lohneys (p. 99), 3 copper to 9 +or 10 lead. Schlüter (p. 479, etc.) insists on a ration of 3 copper to +about 11 lead. Kerl (_Handbuch Der Metallurgischen Hüttenkunde_, 1855; +Vol. III., p. 116) gives 3 copper to 6 to 7 parts lead. Agricola gives +variable amounts of 3 parts copper to from 8 to 12 parts lead. As to the +ratio of silver in the copper, or to the cakes, there does not, except +the limit of payability, seem to have been any difficulty on the minimum +side. On the other hand, Ercker, Lohneys, Schlüter, and Karsten all +contend that if the silver ran above a certain proportion, the copper +would retain considerable silver. These authors give the outside ratio +of silver permissible for good results in one liquation at what would be +equivalent to 45 to 65 ozs. per ton of cakes, or about 190 to 250 ozs. +per ton on the original copper. It will be seen, however, that +Agricola's cakes greatly exceed these values. A difficulty did arise +when the copper ran low in silver, in that the liquated lead was too +poor to cupel, and in such case the lead was used over again, until it +became rich enough for this purpose. According to Karsten, copper +containing less than an equivalent of 80 to 90 ozs. per ton could not be +liquated profitably, although the Upper Harz copper, according to Kerl, +containing the equivalent of about 50 ozs. per ton, was liquated at a +profit. In such a case the cakes would run only 12 to 14 ozs. per ton. +It will be noticed that in the eight cases given by Agricola the copper +ran from 97 to over 580 ozs. per ton, and in the description of +enrichment of copper "bottoms" the original copper runs 85 ozs., and "it +cannot be separated easily"; as a result, it is raised to 110 ozs. per +ton before treatment. In addition to the following tabulation of the +proportions here given by Agricola, the reader should refer to footnotes +15 and 17, where four more combinations are tabulated. It will be +observed from this table that with the increasing richness of copper an +increased proportion of lead was added, so that the products were of +similar value. It has been assumed (see footnote 13 p. 509), that Roman +weights are intended. It is not to be expected that metallurgical +results of this period will "tie up" with the exactness of the modern +operator's, and it has not been considered necessary to calculate beyond +the nearest pennyweight. Where two or more values are given by the +author the average has been taken. + + + 1ST CHARGE. 2ND CHARGE. 3RD CHARGE. 4TH CHARGE. + + Amount of 211.8 lbs. 211.8 lbs. 211.8 lbs. 211.8 lbs. + argentiferous copper + + Amount of lead 564.8 " 635.4 " 776.6 " 847.2 " + + Weight of each cake 193.5 " 211.5 " 247.1 " 264.75 " + + Average value of 56 ozs. 62 ozs. 64 ozs. 66 ozs. + charge 3dwts. 4dwts. 4dwts. 7dwts. + + Per cent. of copper 27.2% 25% 21.4% 20% + + Average value of 207 ozs. 251 ozs. 299 ozs. 332 ozs. + original copper 4dwts. 3dwts. 15dwts. 3dwts. + per ton + + Weight of 423.6 lbs. 494.2 lbs. 635.4 lbs. 706 lbs. + argentiferous lead + liquated out + + Average value of 79 ozs. 79 ozs. 79 ozs. 85 ozs. + liquated lead + per ton + + Weight of residues 353 lbs. 353 lbs. 353 lbs. 353 lbs. + (residual copper + and thorns) + + Average value of 34 ozs. 34 ozs. 34 ozs. 34 ozs. to + residues per ton 38 ozs. + + Extraction of 76.5% 73.4% 79% 85.3% + silver into the + argentiferous lead + +[11] See p. 356. + +[12] An analysis of this "slag" by Karsten (_Archiv_. 1st Series IX, p. +24) showed 63.2% lead oxide, 5.1% cuprous oxide, 20.1% silica (from the +fuel and furnace linings), together with some iron alumina, etc. The +_pompholyx_ and _spodos_ were largely zinc oxide (see note, p. 394). + +[13] This description of a _centumpondium_ which weighed either 133-1/3 +_librae_, or 146-3/4 _librae_, adds confusion to an already much mixed +subject (see Appendix C.). Assuming the German _pfundt_ to weigh 7,219 +troy grains, and the Roman _libra_ 4,946 grains, then a _centner_ would +weigh 145.95 _librae_, which checks up fairly well with the second case; +but under what circumstances a _centner_ can weigh 133-1/3 _librae_ we +are unable to record. At first sight it might appear from this statement +that where Agricola uses the word _centumpondium_ he means the German +_centner_. On the other hand, in the previous five or six pages the +expressions one-third, five-sixths, ten-twelfths of a _libra_ are used, +which are even divisions of the Roman 12 _unciae_ to one _libra_, and +are used where they manifestly mean divisions of 12 units. If Agricola +had in mind the German scale, and were using the _libra_ for a _pfundt_ +of 16 _untzen_, these divisions would amount to fractions, and would not +total the _sicilicus_ and _drachma_ quantities given, nor would they +total any of the possibly synonymous divisions of the German _untzen_ +(see also page 254). + +[14] If we assume Roman weights, the charge in the first case can be +tabulated as follows, and for convenience will be called the fifth +charge:-- + + 5TH CHARGE (3 cakes). + Amount of copper 211.8 lbs. + Amount of lead 635.4 lbs. + Weight of each cake 282.4 lbs. + Average value of charge 218 ozs. 18 dwts. + Per cent. of copper 25% + Average value of original copper per ton 583 ozs. 6 dwts. 16 grs. + Weight of argentiferous lead liquated out 494.2 lbs. + Average value of liquated lead per ton 352 ozs. 8 dwts. + Weight of residues 353 lbs. + Average value of residues per ton 20 ozs. (about). + Extraction of silver into the argentiferous lead 94% + +The results given in the second case where the copper contains 2 +_librae_ and a _bes_ per _centumpondium_ do not tie together at all, for +each liquation cake should contain 3 _librae_ 9-1/2 _unciae_, instead of +1-1/2 _librae_ and 1/2 _uncia_ of silver. + +[15] In this enrichment of copper by the "settling" of the silver in the +molten mass the original copper ran, in the two cases given, 60 ozs. 15 +dwts. and 85 ozs. 1 dwt. per ton. The whole charge weighed 2,685 lbs., +and contained in the second case 114 ozs. Troy, omitting fractions. On +melting, 1,060 lbs. were drawn off as "tops," containing 24 ozs. of +silver, or running 45 ozs. per ton, and there remained 1,625 lbs. of +"bottoms," containing 90 ozs. of silver, or averaging 110 ozs. per ton. +It will be noticed later on in the description of making liquation cakes +from these copper bottoms, that the author alters the value from +one-third _librae_, a _semi-uncia_ and a _drachma_ per _centumpondium_ +to one-third of a _libra_, _i.e._, from 110 ozs. to 97 ozs. 4 dwts. per +ton. In the Glossary this furnace is described as a _spleisofen_, +_i.e._, a refining hearth. + +[16] The latter part of this paragraph presents great difficulties. The +term "refining furnace" is given in the Latin as the "second furnace," +an expression usually applied to the cupellation furnace. The whole +question of refining is exhaustively discussed on pages 530 to 539. +Exactly what material is meant by the term red (_rubrum_), yellow +(_fulvum_) and _caldarium_ copper is somewhat uncertain. They are given +in the German text simply as _rot_, _geel_, and _lebeter kupfer_, and +apparently all were "coarse" copper of different characters destined for +the refinery. The author states in _De Natura Fossilium_ (p. 334): +"Copper has a red colour peculiar to itself; this colour in smelted +copper is considered the most excellent. It, however, varies. In some it +is red, as in the copper smelted at Neusohl.... Other copper is prepared +in the smelters where silver is separated from copper, which is called +yellow copper (_luteum_), and is _regulare_. In the same place a dark +yellow copper is made which is called _caldarium_, taking its name among +the Germans from a caldron.... _Regulare_ differs from _caldarium_ in +that the former is not only fusible, but also malleable; while the +latter is, indeed, fusible, but is not ductile, for it breaks when +struck with the hammer." Later on in _De Re Metallica_ (p. 542) he +describes yellow copper as made from "baser" liquation thorns and from +exhausted liquation cakes made from thorns. These products were +necessarily impure, as they contained, among other things, the +concentrates from furnace accretions. Therefore, there was ample source +for zinc, arsenic or other metallics which would lighten the colour. +_Caldarium_ copper is described by Pliny (see note, p. 404), and was, no +doubt, "coarse" copper, and apparently Agricola adopted this term from +that source, as we have found it used nowhere else. On page 542 the +author describes making _caldarium_ copper from a mixture of yellow +copper and a peculiar _cadmia_, which he describes as the "slags" from +refining copper. These "slags," which are the result of oxidation and +poling, would contain almost any of the metallic impurities of the +original ore, antimony, lead, arsenic, zinc, cobalt, etc. Coming from +these two sources the _caldarium_ must have been, indeed, impure. + +[17] The liquation of these low-grade copper "bottoms" required that the +liquated lead should be re-used again to make up fresh liquation cakes, +in order that it might eventually become rich enough to warrant +cupellation. In the following table the "poor" silver-lead is designated +(A) the "medium" (B) and the "rich" (C). The three charges here given +are designated sixth, seventh, and eighth for purposes of reference. It +will be seen that the data is insufficient to complete the ninth and +tenth. Moreover, while the author gives directions for making four +cakes, he says the charge consists of five, and it has, therefore, been +necessary to reduce the volume of products given to this basis. + + 6TH CHARGE. 7TH CHARGE. 8TH CHARGE. + + Amount of copper 176.5 lbs. 176.5 lbs. 176.5 lbs. + bottoms + + Amount of lead 282.4 lbs. 564.8 lbs. 635.4 lbs. + (slags) of (A) of (B) + + Amount of 494.2 lbs. 211.8 lbs. 141.2 lbs. (A) + de-silverized lead + + Weight of each cake 238.3 lbs. 238.3 lbs. 238.3 lbs. + + Average value of 22 ozs. 35 ozs. 50 ozs. + charge per ton 5dwts. 15dwts. 5dwts. + + Per cent. of copper 18.5% 18.5% 18.5% + + Average value per 97 ozs. 97 ozs. 97 ozs. + ton original copper 4dwts. 4dwts. 4dwts. + + Average value per 90 ozs. 28 ozs. 28 ozs. + ton of 2dwts. (slags) 5dwts. (A) 5dwts. (A) + + Average value per 3 ozs. 3 ozs. 42 ozs. + ton of 1dwt. (lead) 1dwt. (lead) 10dwts. (B) + + Weight of liquated 550.6 lbs. + lead + + Average value of 28 ozs. 42 ozs. 63 ozs. + the liquated lead 5dwts. (A) 10dwts. (B) 16dwts. (C) + per ton + + Weight of exhausted 225.9 lbs. + liquation cakes + + Average value of 12 ozs. + the exhausted 3dwts. + liquation cakes + per ton + + Weight of liquation 169.4 lbs. + thorns + + Average value of 18 ozs. + the liquation 4dwts. + thorns per ton + + Extraction of 71% + silver into the + liquated lead + + +[18] For the liquation it was necessary to maintain a reducing +atmosphere, otherwise the lead would oxidize; this was secured by +keeping the cakes well covered with charcoal and by preventing the +entrance of air as much as possible. Moreover, it was necessary to +preserve a fairly even temperature. The proportions of copper and lead +in the three liquation products vary considerably, depending upon the +method of conducting the process and the original proportions. From the +authors consulted (see note p. 492) an average would be about as +follows:--The residual copper--exhausted liquation cakes--ran from 25 to +33% lead; the liquated lead from 2 to 3% copper; and the liquation +thorns, which were largely oxidized, contained about 15% copper oxides, +80% lead oxides, together with impurities, such as antimony, arsenic, +etc. The proportions of the various products would obviously depend upon +the care in conducting the operation; too high temperature and the +admission of air would increase the copper melted and oxidize more lead, +and thus increase the liquation thorns. There are insufficient data in +Agricola to adduce conclusions as to the actual ratios produced. The +results given for the 6th charge (note 17, p. 512) would indicate about +30% lead in the residual copper, and would indicate that the original +charge was divided into about 24% of residual copper, 18% of liquation +thorns, and 57% of liquated lead. This, however, was an unusually large +proportion of liquation thorns, some of the authors giving instances of +as low as 5%. + +[19] The first instance given, of 44 _centumpondia_ (3,109 lbs.) lead +and one _centumpondium_ (70.6 lbs.) copper, would indicate that the +liquated lead contained 2.2% copper. The second, of 46 _centumpondia_ +(3,250 lbs.) lead and 1-1/2 _centumpondia_ copper (106 lbs.), would +indicate 3% copper; and in the third, 120 _centumpondia_ (8,478 lbs.) +lead and six copper (424 lbs.) would show 4.76% copper. This charge of +120 _centumpondia_ in the cupellation furnace would normally make more +than 110 _centumpondia_ of litharge and 30 of hearth-lead, _i.e._, +saturated furnace bottoms. The copper would be largely found in the +silver-lead "which does not melt," at the margin of the crucible. These +skimmings are afterward referred to as "thorns." It is difficult to +understand what is meant by the expression that the silver which is in +the copper is mixed with the remaining (_reliquo_) silver. The coppery +skimmings from the cupellation furnace are referred to again in Note 28, +p. 539. + +[20] A further amount of lead could be obtained in the first liquation, +but a higher temperature is necessary, which was more economical to +secure in the "drying" furnace. Therefore, the "drying" was really an +extension of liquation; but as air was admitted the lead and copper +melted out were oxidized. The products were the final residual copper, +called by Agricola the "dried" copper, together with lead and copper +oxides, called by him the "slags," and the scale of copper and lead +oxides termed by him the "ash-coloured copper." The German metallurgists +distinguished two kinds of slag: the first and principal one, the +_darrost_, and the second the _darrsöhle_, this latter differing only in +that it contained more impurities from the floor of the furnace, and +remained behind until the furnace cooled. Agricola possibly refers to +these as "more liquation thorns," because in describing the treatment of +the bye-products he refers to thorns from the process, whereas in the +description of "drying" he usually refers to "slags." A number of +analyses of these products, given by Karsten, show the "dried" copper to +contain from 82.7 to 90.6% copper, and from 9.4 to 17.3% lead; the +"slag" to contain 76.5 to 85.1% lead oxide, and from 4.1 to 7.8% cuprous +oxide, with 9 to 13% silica from the furnace bottoms, together with some +other impurities; the "ash-coloured copper" to contain about 60% cuprous +oxide and 30% lead oxide, with some metallic copper and minor +impurities. An average of proportions given by various authors shows, +roughly, that out of 100 _centners_ of "exhausted" liquation cakes, +containing about 70% copper and 30% lead, there were about 63 _centners_ +of "dried" copper, 38 _centners_ of "slag," and 6-1/2 _centners_ of +"ash-coloured copper." According to Karsten, the process fell into +stages; first, at low temperature some metallic lead appeared; second, +during an increasing temperature for over 14 to 15 hours the slags ran +out; third, there was a period of four hours of lower temperature to +allow time for the lead to diffuse from the interior of the cakes; and +fourth, during a period of eight hours the temperature was again +increased. In fact, the latter portion of the process ended with the +economic limit between leaving some lead in the copper and driving too +much copper into the "slags." Agricola gives the silver contents of the +"dried" copper as 3 _drachmae_ to 1 _centumpondium_, or equal to about 9 +ozs. per ton; and assuming that the copper finally recovered from the +bye-products ran no higher, then the first four charges (see note on p. +506) would show a reduction in the silver values of from 95 to 97%; the +7th and 8th charges (note on p. 512) of about 90%. + +[21] If Roman weights, this would equal from 6,360 lbs. to 7,066 lbs. + +[22] One half _uncia_, or three _drachmae_ of silver would equal either +12 ozs. or 9 ozs. per ton. If we assume the values given for residual +copper in the first four charges (note p. 506) of 34 ozs., this would +mean an extraction of, roughly, 65% of the silver from the exhausted +liquation cakes. + +[23] See note 29, p. 540. + +[24] + + Assuming Roman weights: 2 _centumpondia_ = 141.3 lbs. + 2-1/2 " = 176.6 " + 3 " = 211.9 " + 3-1/2 " = 248.2 " + 6 " = 423.9 " + +[25] This description of refining copper in an open hearth by oxidation +with a blast and "poling"--the _gaarmachen_ of the Germans--is so +accurate, and the process is so little changed in some parts of Saxony, +that it might have been written in the 20th century instead of the 16th. +The best account of the old practice in Saxony after Agricola is to be +found in Schlüter's _Hütte Werken_ (Braunschweig, 1738, Chap. CXVIII.). +The process has largely been displaced by electrolytic methods, but is +still in use in most refineries as a step in electrolytic work. It may +be unnecessary to repeat that the process is one of subjecting the +molten mass of impure metal to a strong and continuous blast, and as a +result, not only are the impurities to a considerable extent directly +oxidized and taken off as a slag, but also a considerable amount of +copper is turned into cuprous oxide. This cuprous oxide mostly melts and +diffuses through the metallic copper, and readily parting with its +oxygen to the impurities further facilitates their complete oxidation. +The blast is continued until the impurities are practically eliminated, +and at this stage the molten metal contains a great deal of dissolved +cuprous oxide, which must be reduced. This is done by introducing a +billet of green wood ("poling"), the dry distillation of which generates +large quantities of gases, which reduce the oxide. The state of the +metal is even to-day in some localities tested by dipping into it the +point of an iron rod; if it be at the proper state the adhering copper +has a net-like appearance, should be easily loosened from the rod by +dipping in water, is of a reddish-copper colour and should be quite +pliable; if the metal is not yet refined, the sample is thick, smooth, +and detachable with difficulty; if over-refined, it is thick and +brittle. By allowing water to run on to the surface of the molten metal, +thin cakes are successively formed and taken off. These cakes were the +article known to commerce over several centuries as "rosetta copper." +The first few cakes are discarded as containing impurities or slag, and +if the metal be of good quality the cakes are thin and of a red colour. +Their colour and thinness, therefore, become a criterion of purity. The +cover of charcoal or charcoal dust maintained upon the surface of the +metal tended to retard oxidation, but prevented volatilization and +helped to secure the impurities as a slag instead. Karsten (_Archiv._, +1st series, p. 46) gives several analyses of the slag from refining +"dried" copper, showing it to contain from 51.7 to 67.4% lead oxide, 6.2 +to 19.2% cuprous oxide, and 21.4 to 23.9 silica (from the furnace +bottoms), with minor quantities of iron, antimony, etc. The "bubbles" +referred to by Agricola were apparently the shower of copper globules +which takes place upon the evolution of sulphur dioxide, due to the +reaction of the cuprous oxide upon any remaining sulphide of copper when +the mass begins to cool. + +HISTORICAL NOTE.--It is impossible to say how the Ancients refined +copper, beyond the fact that they often re-smelted it. Such notes as we +can find are set out in the note on copper smelting (note 42, p. 402). +The first authentic reference to poling is in Theophilus (1150 to 1200 +A.D., Hendrie's translation, p. 313), which shows a very good +understanding of this method of refining copper:--"Of the Purification +of Copper. Take an iron dish of the size you wish, and line it inside +and out with clay strongly beaten and mixed, and it is carefully dried. +Then place it before a forge upon the coals, so that when the bellows +act upon it the wind may issue partly within and partly above it, and +not below it. And very small coals being placed round it, place the +copper in it equally, and add over it a heap of coals. When by blowing a +long time this has become melted, uncover it and cast immediately fine +ashes of coals over it, and stir it with a thin and dry piece of wood as +if mixing it, and you will directly see the burnt lead adhere to these +ashes like a glue, which being cast out again superpose coals, and +blowing for a long time, as at first, again uncover it, and then do as +you did before. You do this until at length by cooking it you can +withdraw the lead entirely. Then pour it over the mould which you have +prepared for this, and you will thus prove if it be pure. Hold it with +the pincers, glowing as it is, before it has become cold, and strike it +with a large hammer strongly over the anvil, and if it be broken or +split you must liquefy it anew as before. If, however, it should remain +sound, you will cool it in water, and you cook other (copper) in the +same manner." Biringuccio (III, 8) in 1540 describes the process +briefly, but omits the poling, an essential in the production of +malleable copper. + +[26] _Pompholyx_ and _spodos_ were impure zinc oxides (see note 26, p. +394). + +The copper flowers were no doubt cupric oxide. They were used by the +Ancients for medicinal purposes. Dioscorides (V, 48) says: "Of flowers +of copper, which some call the scrapings of old nails, the best is +friable; it is gold-coloured when rubbed, is like millet in shape and +size, is moderately bright, and somewhat astringent. It should not be +mixed with copper filings, with which it is often adulterated. But this +deception is easily detected, for when bitten in the teeth the filings +are malleable. It (the flowers) is made when the copper fused in a +furnace has run into the receptacle through the spout pertaining to it, +for then the workmen engaged in this trade cleanse it from dirt and pour +clear water over it in order to cool it; from this sudden condensation +the copper spits and throws out the aforesaid flowers." Pliny (XXXIV, +24) says: "The flower, too, of copper (_æris flos_) is used in medicine. +This is made by fusing copper, and then removing it to another furnace, +where the repeated blast makes the metal separate into small scales like +millet, known as flowers. These scales also fall off when the cakes of +metal are cooled in water; they become red, too, like the scales of +copper known as '_lepis_,' by use of which the flowers of copper are +adulterated, it being also sold for it. These are made when hammering +the nails that are made from the cakes of copper. All these methods are +carried on in the works of Cyprus; the difference between these +substances is that the _squamae_ (copper scales) are detached from +hammering the cakes, while the flower falls off spontaneously." Agricola +(_De Nat. Fos._, p. 352) notes that "flowers of copper (_flos æris_) +have the same properties as 'roasted copper.'" + +[27] It seems scarcely necessary to discuss in detail the complicated +"flow scheme" of the various minor bye-products. They are all +re-introduced into the liquation circuit, and thereby are created other +bye-products of the same kind _ad infinitum_. Further notes are given +on:-- + + Liquation thorns Note 28. + Slags " 30. + Ash-coloured copper " 29. + Concentrates " 33. + _Cadmia_ " 32. + +There are no data given, either by Agricola or the later authors, which +allow satisfactory calculation of the relative quantities of these +products. A rough estimate from the data given in previous notes would +indicate that in one liquation only about 70% of the original copper +came out as refined copper, and that about 70% of the original lead +would go to the cupellation furnace, _i.e._, about 30% of the original +metal sent to the blast furnace would go into the "thorns," "slags," and +"ash-coloured copper." The ultimate losses were very great, as given +before (p. 491), they probably amounted to 25% of the silver, 9% copper, +and 16% of the lead. + +[28] There were the following classes of thorns:-- + + 1st. From liquation. + 2nd. From drying. + 3rd. From cupellation. + +In a general way, according to the later authors, they were largely lead +oxide, and contained from 5% to 20% cuprous oxide. If a calculation be +made backward from the products given as the result of the charge +described, it would appear that in this case they must have contained at +least one-fifth copper. The silver in these liquation cakes would run +about 24 ozs. per ton, in the liquated lead about 36 ozs. per ton, and +in the liquation thorns 24 ozs. per ton. The extraction into the +liquated lead would be about 80% of the silver. + +[29] The "ash-coloured copper" is a cuprous oxide, containing some 3% +lead oxide; and if Agricola means they contained two _unciae_ of silver +to the _centumpondium_, then they ran about 48 ozs. per ton, and would +contain much more silver than the mass. + +[30] There are three principal "slags" mentioned-- + + 1st. Slag from "leading." + 2nd. Slag from "drying." + 3rd. Slag from refining the copper. + +From the analyses quoted by various authors these ran from 52% to 85% +lead oxide, 5% to 30% cuprous oxide, and considerable silica from the +furnace bottoms. They were reduced in the main into liquation cakes, +although Agricola mentions instances of the metal reduced from "slags" +being taken directly to the "drying" furnace. Such liquation cakes would +run very low in silver, and at the values given only averaged 12 ozs. +per ton; therefore the liquated lead running the same value as the +cakes, or less than half that of the "poor" lead mentioned in Note 17, +p. 512, could not have been cupelled directly. + +[31] See Note 16, p. 511, for discussion of yellow and _caldarium_ +copper. + +[32] This _cadmia_ is given in the Glossary and the German translation +as _kobelt_. A discussion of this substance is given in the note on p. +112; and it is sufficient to state here that in Agricola's time the +metal cobalt was unknown, and the substances designated _cadmia_ and +_cobaltum_ were arsenical-cobalt-zinc minerals. A metal made from "slag" +from refining, together with "base" thorns, would be very impure; for +the latter, according to the paragraph on concentrates a little later +on, would contain the furnace accretions, and would thus be undoubtedly +zincky. It is just possible that the term _kobelt_ was used by the +German smelters at this time in the sense of an epithet--"black devil" +(see Note 21, p. 214). + +[33] It is somewhat difficult to see exactly the meaning of base +(_vile_) and precious (_preciosum_) in this connection. While "base" +could mean impure, "precious" could hardly mean pure, and while +"precious" could mean high value in silver, the reverse does not seem +entirely _apropos_. It is possible that "bad" and "good" would be more +appropriate terms. + +[34] The skimmings from the molten lead in the early stages of +cupellation have been discussed in Note 28, p. 539. They are probably +called thorns here because of the large amount of copper in them. The +lead from liquation would contain 2% to 3% of copper, and this would be +largely recovered in these skimmings, although there would be some +copper in the furnace bottoms--hearth-lead--and the litharge. These +"thorns" are apparently fairly rich, four _unciae_ to the +_centumpondium_ being equivalent to about 97 ozs. per ton, and they are +only added to low-grade liquation material. + +[35] _Particulis aeris tusi_. Unless this be the fine concentrates from +crushing the material mentioned, we are unable to explain the +expression. + +[36] This operation would bring down a button of antimony under an iron +matte, by de-sulphurizing the antimony. It would seem scarcely necessary +to add lead before cupellation. This process is given in an assay +method, in the _Probierbüchlein_ (folio 31) 50 years before _De Re +Metallica_: "How to separate silver from iron: Take that silver which is +in iron _plechen_ (_plachmal_), pulverize it finely, take the same iron +or _plec_ one part, _spiesglasz_ (antimony sulphide) one part, leave +them to melt in a crucible placed in a closed _windtofen_. When it is +melted, let it cool, break the crucible, chip off the button that is in +the bottom, and melt it in a crucible with as much lead. Then break the +crucible, and seek from the button in the cupel, and you will find what +silver it contains." + + + + +BOOK XII. + + +Previously I have dealt with the methods of separating silver from +copper. There now remains the portion which treats of solidified juices; +and whereas they might be considered as alien to things metallic, +nevertheless, the reasons why they should not be separated from it I +have explained in the second book. + +Solidified juices are either prepared from waters in which nature or art +has infused them, or they are produced from the liquid juices +themselves, or from stony minerals. Sagacious people, at first observing +the waters of some lakes to be naturally full of juices which thickened +on being dried up by the heat of the sun and thus became solidified +juices, drew such waters into other places, or diverted them into +low-lying places adjoining hills, so that the heat of the sun should +likewise cause them to condense. Subsequently, because they observed +that in this wise the solidified juices could be made only in summer, +and then not in all countries, but only in hot and temperate regions in +which it seldom rains in summer, they boiled them in vessels over a fire +until they began to thicken. In this manner, at all times of the year, +in all regions, even the coldest, solidified juices could be obtained +from solutions of such juices, whether made by nature or by art. +Afterward, when they saw juices drip from some roasted stones, they +cooked these in pots in order to obtain solidified juices in this wise +also. It is worth the trouble to learn the proportions and the methods +by which these are made. + +I will therefore begin with salt, which is made from water either salty +by nature, or by the labour of man, or else from a solution of salt, or +from lye, likewise salty. Water which is salty by nature, is condensed +and converted into salt in salt-pits by the heat of the sun, or else by +the heat of a fire in pans or pots or trenches. That which is made salty +by art, is also condensed by fire and changed into salt. There should be +as many salt-pits dug as the circumstance of the place permits, but +there should not be more made than can be used, although we ought to +make as much salt as we can sell. The depth of salt-pits should be +moderate, and the bottom should be level, so that all the water is +evaporated from the salt by the heat of the sun. The salt-pits should +first be encrusted with salt, so that they may not suck up the water. +The method of pouring or leading sea-water into salt-pits is very old, +and is still in use in many places. The method is not less old, but less +common, to pour well-water into salt-pits, as was done in Babylon, for +which Pliny is the authority, and in Cappadocia, where they used not +only well-water, but also spring-water. In all hot countries salt-water +and lake-water are conducted, poured or carried into salt-pits, and, +being dried by the heat of the sun, are converted into salt.[1] While +the salt-water contained in the salt-pits is being heated by the sun, if +they be flooded with great and frequent showers of rain the evaporation +is hindered. If this happens rarely, the salt acquires a disagreeable[2] +flavour, and in this case the salt-pits have to be filled with other +sweet water. + +[Illustration 547 (Salt Pans): A--Sea. B--Pool. C--Gate. D--Trenches. +E--Salt basins. F--Rake. G--Shovel.] + +Salt from sea-water is made in the following manner. Near that part of +the seashore where there is a quiet pool, and there are wide, level +plains which the inundations of the sea do not overflow, three, four, +five, or six trenches are dug six feet wide, twelve feet deep, and six +hundred feet long, or longer if the level place extends for a longer +distance; they are two hundred feet distant from one another; between +these are three transverse trenches. Then are dug the principal pits, so +that when the water has been raised from the pool it can flow into the +trenches, and from thence into the salt-pits, of which there are numbers +on the level ground between the trenches. The salt-pits are basins dug +to a moderate depth; these are banked round with the earth which was dug +in sinking them or in cleansing them, so that between the basins, earth +walls are made a foot high, which retain the water let into them. The +trenches have openings, through which the first basins receive the +water; these basins also have openings, through which the water flows +again from one into the other. There should be a slight fall, so that +the water may flow from one basin into the other, and can thus be +replenished. All these things having been done rightly and in order, the +gate is raised that opens the mouth of the pool which contains sea-water +mixed with rain-water or river-water; and thus all of the trenches are +filled. Then the gates of the first basins are opened, and thus the +remaining basins are filled with the water from the first; when this +salt-water condenses, all these basins are incrusted, and thus made +clean from earthy matter. Then again the first basins are filled up from +the nearest trench with the same kind of water, and left until much of +the thin liquid is converted into vapour by the heat of the sun and +dissipated, and the remainder is considerably thickened. Then their +gates being opened, the water passes into the second basins; and when it +has remained there for a certain space of time the gates are opened, so +that it flows into the third basins, where it is all condensed into +salt. After the salt has been taken out, the basins are filled again and +again with sea-water. The salt is raked up with wooden rakes and thrown +out with shovels. + +[Illustration 549 (Salt Wells): A--Shed. B--Painted signs. C--First +room. D--Middle room. E--Third room. F--Two little windows in the end +wall. G--Third little window in the roof. H--Well. I--Well of another +kind. K--Cask. L--Pole. M--Forked sticks in which the porters rest the +pole when they are tired.] + +Salt-water is also boiled in pans, placed in sheds near the wells from +which it is drawn. Each shed is usually named from some animal or other +thing which is pictured on a tablet nailed to it. The walls of these +sheds are made either from baked earth or from wicker work covered with +thick mud, although some may be made of stones or bricks. When of +brick they are often sixteen feet high, and if the roof rises +twenty-four feet high, then the walls which are at the ends must be made +forty feet high, as likewise the interior partition walls. The roof +consists of large shingles four feet long, one foot wide, and two digits +thick; these are fixed on long narrow planks placed on the rafters, +which are joined at the upper end and slope in opposite directions. The +whole of the under side is plastered one digit thick with straw mixed +with lute; likewise the roof on the outside is plastered one and a half +feet thick with straw mixed with lute, in order that the shed should not +run any risk of fire, and that it should be proof against rain, and be +able to retain the heat necessary for drying the lumps of salt. Each +shed is divided into three parts, in the first of which the firewood and +straw are placed; in the middle room, separated from the first room by a +partition, is the fireplace on which is placed the caldron. To the right +of the caldron is a tub, into which is emptied the brine brought into +the shed by the porters; to the left is a bench, on which there is room +to lay thirty pieces of salt. In the third room, which is in the back +part of the house, there is made a pile of clay or ashes eight feet +higher than the floor, being the same height as the bench. The master +and his assistants, when they carry away the lumps of salt from the +caldrons, go from the former to the latter. They ascend from the right +side of the caldron, not by steps, but by a slope of earth. At the top +of the end wall are two small windows, and a third is in the roof, +through which the smoke escapes. This smoke, emitted from both the back +and the front of the furnace, finds outlet through a hood through which +it makes its way up to the windows; this hood consists of boards +projecting one beyond the other, which are supported by two small beams +of the roof. Opposite the fireplace the middle partition has an open +door eight feet high and four feet wide, through which there is a gentle +draught which drives the smoke into the last room; the front wall also +has a door of the same height and width. Both of these doors are large +enough to permit the firewood or straw or the brine to be carried in, +and the lumps of salt to be carried out; these doors must be closed when +the wind blows, so that the boiling will not be hindered. Indeed, glass +panes which exclude the wind but transmit the light, should be inserted +in the windows in the walls. + +They construct the greater part of the fireplace of rock-salt and of +clay mixed with salt and moistened with brine, for such walls are +greatly hardened by the fire. These fireplaces are made eight and a half +feet long, seven and three quarters feet wide, and, if wood is burned in +them, nearly four feet high; but if straw is burned in them, they are +six feet high. An iron rod, about four feet long, is engaged in a hole +in an iron foot, which stands on the base of the middle of the furnace +mouth. This mouth is three feet in width, and has a door which opens +inward; through it they throw in the straw. + +[Illustration 551 (Salt Caldron): A--Fireplace. B--Mouth of fireplace. +C--Caldron. D--Posts sunk into the ground. E--Cross-beams. F--Shorter +bars. G--Iron hooks. H--Staples. I--Longer bars. K--Iron rod bent to +support the caldron.] + +The caldrons are rectangular, eight feet long, seven feet wide, and half +a foot high, and are made of sheets of iron or lead, three feet long and +of the same width, all but two digits. These plates are not very thick, +so that the water is heated more quickly by the fire, and is boiled +away rapidly. The more salty the water is, the sooner it is condensed +into salt. To prevent the brine from leaking out at the points where the +metal plates are fastened with rivets, the caldrons are smeared over +with a cement made of ox-liver and ox-blood mixed with ashes. On each +side of the middle of the furnace two rectangular posts, three feet +long, and half a foot thick and wide are set into the ground, so that +they are distant from each other only one and a half feet. Each of them +rises one and a half feet above the caldron. After the caldron has been +placed on the walls of the furnace, two beams of the same width and +thickness as the posts, but four feet long, are laid on these posts, and +are mortised in so that they shall not fall. There rest transversely +upon these beams three bars, three feet long, three digits wide, and two +digits thick, distant from one another one foot. On each of these hang +three iron hooks, two beyond the beams and one in the middle; these are +a foot long, and are hooked at both ends, one hook turning to the right, +the other to the left. The bottom hook catches in the eye of a staple, +whose ends are fixed in the bottom of the caldron, and the eye projects +from it. There are besides, two longer bars six feet long, one palm +wide, and three digits thick, which pass under the front beam and rest +upon the rear beam. At the rear end of each of the bars there is an iron +hook two feet and three digits long, the lower end of which is bent so +as to support the caldron. The rear end of the caldron does not rest on +the two rear corners of the fireplace, but is distant from the fireplace +two thirds of a foot, so that the flame and smoke can escape; this rear +end of the fireplace is half a foot thick and half a foot higher than +the caldron. This is also the thickness and height of the wall between +the caldron and the third room of the shed, to which it is adjacent. +This back wall is made of clay and ashes, unlike the others which are +made of rock-salt. The caldron rests on the two front corners and sides +of the fireplace, and is cemented with ashes, so that the flames shall +not escape. If a dipperful of brine poured into the caldron should flow +into all the corners, the caldron is rightly set upon the fireplace. + +The wooden dipper holds ten Roman _sextarii_, and the cask holds eight +dippers full[3]. The brine drawn up from the well is poured into such +casks and carried by porters, as I have said before, into the shed and +poured into a tub, and in those places where the brine is very strong it +is at once transferred with the dippers into the caldron. That brine +which is less strong is thrown into a small tub with a deep ladle, the +spoon and handle of which are hewn out of one piece of wood. In this tub +rock-salt is placed in order that the water should be made more salty, +and it is then run off through a launder which leads into the caldron. +From thirty-seven dippersful of brine the master or his deputy, at Halle +in Saxony,[4] makes two cone-shaped pieces of salt. Each master has a +helper, or in the place of a helper his wife assists him in his work, +and, in addition, a youth who throws wood or straw under the caldron. +He, on account of the great heat of the workshop, wears a straw cap on +his head and a breech cloth, being otherwise quite naked. As soon as the +master has poured the first dipperful of brine into the caldron the +youth sets fire to the wood and straw laid under it. If the firewood is +bundles of faggots or brushwood, the salt will be white, but if straw is +burned, then it is not infrequently blackish, for the sparks, which are +drawn up with the smoke into the hood, fall down again into the water +and colour it black. + +[Illustration 553 (Salt Caldron): A--Wooden dipper. B--Cask. C--Tub. +D--Master. E--Youth. F--Wife. G--Wooden spade. H--Boards. I--Baskets. +K--Hoe. L--Rake. M--Straw. N--Bowl. O--Bucket containing the blood. +P--Tankard which contains beer.] + +In order to accelerate the condensation of the brine, when the master +has poured in two casks and as many dippersful of brine, he adds about a +Roman _cyathus_ and a half of bullock's blood, or of calf's blood, or +buck's blood, or else he mixes it into the nineteenth dipperful of +brine, in order that it may be dissolved and distributed into all the +corners of the caldron; in other places the blood is dissolved in beer. +When the boiling water seems to be mixed with scum, he skims it with a +ladle; this scum, if he be working with rock-salt, he throws into the +opening in the furnace through which the smoke escapes, and it is dried +into rock-salt; if it be not from rock-salt, he pours it on to the floor +of the workshop. From the beginning to the boiling and skimming is the +work of half-an-hour; after this it boils down for another +quarter-of-an-hour, after which time it begins to condense into salt. +When it begins to thicken with the heat, he and his helper stir it +assiduously with a wooden spatula, and then he allows it to boil for an +hour. After this he pours in a _cyathus_ and a half of beer. In order +that the wind should not blow into the caldron, the helper covers the +front with a board seven and a half feet long and one foot high, and +covers each of the sides with boards three and three quarters feet long. +In order that the front board may hold more firmly, it is fitted into +the caldron itself, and the side-boards are fixed on the front board and +upon the transverse beam. Afterward, when the boards have been lifted +off, the helper places two baskets, two feet high and as many wide at +the top, and a palm wide at the bottom, on the transverse beams, and +into them the master throws the salt with a shovel, taking half-an-hour +to fill them. Then, replacing the boards on the caldron, he allows the +brine to boil for three quarters of an hour. Afterward the salt has +again to be removed with a shovel, and when the baskets are full, they +pile up the salt in heaps. + +In different localities the salt is moulded into different shapes. In +the baskets the salt assumes the form of a cone; it is not moulded in +baskets alone, but also in moulds into which they throw the salt, which +are made in the likeness of many objects, as for instance tablets. +These tablets and cones are kept in the higher part of the third room of +the house, or else on the flat bench of the same height, in order that +they may dry better in the warm air. In the manner I have described, a +master and his helper continue one after the other, alternately boiling +the brine and moulding the salt, day and night, with the exception only +of the annual feast days. No caldron is able to stand the fire for more +than half a year. The master pours in water and washes it out every +week; when it is washed out he puts straw under it and pounds it; new +caldrons he washes three times in the first two weeks, and afterward +twice. In this manner the incrustations fall from the bottom; if they +are not cleared off, the salt would have to be made more slowly over a +fiercer fire, which requires more brine and burns the plates of the +caldron. If any cracks make their appearance in the caldron they are +filled up with cement. The salt made during the first two weeks is not +so good, being usually stained by the rust at the bottom where +incrustations have not yet adhered. + +Although salt made in this manner is prepared only from the brine of +springs and wells, yet it is also possible to use this method in the +case of river-, lake-, and sea-water, and also of those waters which are +artificially salted. For in places where rock-salt is dug, the impure +and the broken pieces are thrown into fresh water, which, when boiled, +condenses into salt. Some, indeed, boil sea-salt in fresh water again, +and mould the salt into the little cones and other shapes. + +[Illustration 554 (Salt Boiling): A--Pool. B--Pots. C--Ladle. D--Pans. +E--Tongs.] + +Some people make salt by another method, from salt water which flows +from hot springs that issue boiling from the earth. They set earthenware +pots in a pool of the spring-water, and into them they pour water +scooped up with ladles from the hot spring until they are half full. The +perpetual heat of the waters of the pool evaporates the salt water just +as the heat of the fire does in the caldrons. As soon as it begins to +thicken, which happens when it has been reduced by boiling to a third or +more, they seize the pots with tongs and pour the contents into small +rectangular iron pans, which have also been placed in the pool. The +interior of these pans is usually three feet long, two feet wide, and +three digits deep, and they stand on four heavy legs, so that the water +flows freely all round, but not into them. Since the water flows +continuously from the pool through the little canals, and the spring +always provides a new and copious supply, always boiling hot, it +condenses the thickened water poured into the pans into salt; this is at +once taken out with shovels, and then the work begins all over again. If +the salty water contains other juices, as is usually the case with hot +springs, no salt should be made from them. + +[Illustration 555 (Salt Boiling): A--Pots. B--Tripod. C--Deep ladle.] + +Others boil salt water, and especially sea-water, in large iron pots; +this salt is blackish, for in most cases they burn straw under them. +Some people boil in these pots the brine in which fish is pickled. The +salt which they make tastes and smells of fish. + +[Illustration 556 (Salt evaporated on faggots): A--Trench. B--Vat into +which the salt water flows. C--Ladle. D--Small bucket with pole fastened +into it.] + +Those who make salt by pouring brine over firewood, lay the wood in +trenches which are twelve feet long, seven feet wide, and two and one +half feet deep, so that the water poured in should not flow out. These +trenches are constructed of rock-salt wherever it is to be had, in order +that they should not soak up the water, and so that the earth should not +fall in on the front, back and sides. As the charcoal is turned into +salt at the same time as the salt liquor, the Spaniards think, as +Pliny writes[5], that the wood itself turns into salt. Oak is the best +wood, as its pure ash yields salt; elsewhere hazel-wood is lauded. But +with whatever wood it be made, this salt is not greatly appreciated, +being black and not quite pure; on that account this method of +salt-making is disdained by the Germans and Spaniards. + +[Illustration 557 (Lye Making): A--Large vat. B--Plug. C--Small tub. +D--Deep ladle. E--Small vat. F--Caldron.] + +The solutions from which salt is made are prepared from salty earth or +from earth rich in salt and saltpetre. Lye is made from the ashes of +reeds and rushes. The solution obtained from salty earth by boiling, +makes salt only; from the other, of which I will speak more a little +later, salt and saltpetre are made; and from ashes is derived lye, from +which its own salt is obtained. The ashes, as well as the earth, should +first be put into a large vat; then fresh water should be poured over +the ashes or earth, and it should be stirred for about twelve hours with +a stick, so that it may dissolve the salt. Then the plug is pulled out +of the large vat; the solution of salt or the lye is drained into a +small tub and emptied with ladles into small vats; finally, such a +solution is transferred into iron or lead caldrons and boiled, until the +water having evaporated, the juices are condensed into salt. The above +are the various methods for making salt. (Illustration p. 557.) + +[Illustration 559 (Nitrum-pits): A--Nile. B--Nitrum-pits, such as I +conjecture them to be.[7]] + +_Nitrum_[6] is usually made from _nitrous_ waters, or from solutions or +from lye. In the same manner as sea-water or salt-water is poured into +salt-pits and evaporated by the heat of the sun and changed into salt, +so the _nitrous_ Nile is led into _nitrum_ pits and evaporated by the +heat of the sun and converted into _nitrum_. Just as the sea, in +flowing of its own will over the soil of this same Egypt, is changed +into salt, so also the Nile, when it overflows in the dog days, is +converted into _nitrum_ when it flows into the _nitrum_ pits. The +solution from which _nitrum_ is produced is obtained from fresh water +percolating through _nitrous_ earth, in the same manner as lye is made +from fresh water percolating through ashes of oak or hard oak. Both +solutions are taken out of vats and poured into rectangular copper +caldrons, and are boiled until at last they condense into _nitrum_. + +[Illustration 561 (Soda Making): A--Vat in which the soda is mixed. +B--Caldron. C--Tub in which _chrysocolla_ is condensed. D--Copper wires. +E--Mortar.] + +Native as well as manufactured _nitrum_ is mixed in vats with urine and +boiled in the same caldrons; the decoction is poured into vats in which +are copper wires, and, adhering to them, it hardens and becomes +_chrysocolla_, which the Moors call _borax_. Formerly _nitrum_ was +compounded with Cyprian verdigris, and ground with Cyprian copper in +Cyprian mortars, as Pliny writes. Some _chrysocolla_ is made of +rock-alum and sal-ammoniac.[8] + +[Illustration 563 (Saltpetre Making): A--Caldron. B--Large vat into +which sand is thrown. C--Plug. D--Tub. E--Vat containing the rods.] + +Saltpetre[9] is made from a dry, slightly fatty earth, which, if it be +retained for a while in the mouth, has an acrid and salty taste. This +earth, together with a powder, are alternately put into a vat in layers +a palm deep. The powder consists of two parts of unslaked lime and three +parts of ashes of oak, or holmoak, or Italian oak, or Turkey oak, or of +some similar kind. Each vat is filled with alternate layers of these to +within three-quarters of a foot of the top, and then water is poured in +until it is full. As the water percolates through the material it +dissolves the saltpetre; then, the plug being pulled out from the vat, +the solution is drained into a tub and ladled out into small vats. If +when tested it tastes very salty, and at the same time acrid, it is +good; but, if not, then it is condemned, and it must be made to +percolate again through the same material or through a fresh lot. Even +two or three waters may be made to percolate through the same earth and +become full of saltpetre, but the solutions thus obtained must not be +mixed together unless all have the same taste, which rarely or never +happens. The first of these solutions is poured into the first vat, the +next into the second, the third into the third vat; the second and third +solutions are used instead of plain water to percolate through fresh +material; the first solution is made in this manner from both the second +and third. As soon as there is an abundance of this solution it is +poured into the rectangular copper caldron and evaporated to one half by +boiling; then it is transferred into a vat covered with a lid, in which +the earthy matter settles to the bottom. When the solution is clear it +is poured back into the same pan, or into another, and re-boiled. When +it bubbles and forms a scum, in order that it should not run over and +that it may be greatly purified, there is poured into it three or four +pounds of lye, made from three parts of oak or similar ash and one of +unslaked lime. But in the water, prior to its being poured in, is +dissolved rock-alum, in the proportion of one hundred and twenty +_librae_ of the former to five _librae_ of the latter. Shortly +afterward the solution will be found to be clear and blue. It is boiled +until the waters, which are easily volatile (_subtiles_), are +evaporated, and then the greater part of the salt, after it has settled +at the bottom of the pan, is taken out with iron ladles. Then the +concentrated solution is transferred to the vat in which rods are placed +horizontally and vertically, to which it adheres when cold, and if there +be much, it is condensed in three or four days into saltpetre. Then the +solution which has not congealed, is poured out and put on one side or +re-boiled. The saltpetre being cut out and washed with its own solution, +is thrown on to boards that it may drain and dry. The yield of saltpetre +will be much or little in proportion to whether the solution has +absorbed much or little; when the saltpetre has been obtained from lye, +which purifies itself, it is somewhat clear and pure. + +The purest and most transparent, because free from salt, is made if it +is drawn off at the thickening stage, according to the following method. +There are poured into the caldron the same number of _amphorae_ of the +solution as of _congii_ of the lye of which I have already spoken, and +into the same caldron is thrown as much of the already made saltpetre as +the solution and lye will dissolve. As soon as the mixture effervesces +and forms scum, it is transferred to a vat, into which on a cloth has +been thrown washed sand obtained from a river. Soon afterward the plug +is drawn out of the hole at the bottom, and the mixture, having +percolated through the sand, escapes into a tub. It is then reduced by +boiling in one or another of the caldrons, until the greater part of the +solution has evaporated; but as soon as it is well boiled and forms +scum, a little lye is poured into it. Then it is transferred to another +vat in which there are small rods, to which it adheres and congeals in +two days if there is but little of it, or if there is much in three +days, or at the most in four days; if it does not condense, it is poured +back into the caldron and re-boiled down to half; then it is transferred +to the vat to cool. The process must be repeated as often as is +necessary. + +Others refine saltpetre by another method, for with it they fill a pot +made of copper, and, covering it with a copper lid, set it over live +coals, where it is heated until it melts. They do not cement down the +lid, but it has a handle, and can be lifted for them to see whether or +not the melting has taken place. When it has melted, powdered sulphur is +sprinkled in, and if the pot set on the fire does not light it, the +sulphur kindles, whereby the thick, greasy matter floating on the +saltpetre burns up, and when it is consumed the saltpetre is pure. Soon +afterward the pot is removed from the fire, and later, when cold, the +purest saltpetre is taken out, which has the appearance of white marble, +the earthy residue then remains at the bottom. The earths from which the +solution was made, together with branches of oak or similar trees, are +exposed under the open sky and sprinkled with water containing +saltpetre. After remaining thus for five or six years, they are again +ready to be made into a solution. + +Pure saltpetre which has rested many years in the earth, and that which +exudes from the stone walls of wine cellars and dark places, is mixed +with the first solution and evaporated by boiling. + +Thus far I have described the methods of making _nitrum_, which are not +less varied or multifarious than those for making salt. Now I propose to +describe the methods of making alum,[10] which are likewise neither all +alike, nor simple, because it is made from boiling aluminous water until +it condenses to alum, or else from boiling a solution of alum which is +obtained from a kind of earth, or from rocks, or from pyrites, or other +minerals. + +[Illustration 567 (Vitriol Making): A--Tanks. B--Stirring poles. +C--Plug. D--Trough. E--Reservoir. F--Launder. G--lead caldron. H--Wooden +tubs sunk into the earth. I--Vats in which twigs are fixed.] + +This kind of earth having first been dug up in such quantity as would +make three hundred wheelbarrow loads, is thrown into two tanks; then the +water is turned into them, and if it (the earth) contains vitriol it +must be diluted with urine. The workmen must many times a day stir the +ore with long, thick sticks in order that the water and urine may be +mixed with it; then the plugs having been taken out of both tanks, the +solution is drawn off into a trough, which is carved out of one or two +trees. If the locality is supplied with an abundance of such ore, it +should not immediately be thrown into the tanks, but first conveyed into +open spaces and heaped up, for the longer it is exposed to the air and +the rain, the better it is; after some months, during which the ore has +been heaped up in open spaces into mounds, there are generated veinlets +of far better quality than the ore. Then it is conveyed into six or more +tanks, nine feet in length and breadth and five in depth, and afterward +water is drawn into them of similar solution. After this, when the water +has absorbed the alum, the plugs are pulled out, and the solution +escapes into a round reservoir forty feet wide and three feet deep. Then +the ore is thrown out of the tanks into other tanks, and water again +being run into the latter and the urine added and stirred by means of +poles, the plugs are withdrawn and the solution is run off into the same +reservoir. A few days afterward, the reservoirs containing the solution +are emptied through a small launder, and run into rectangular lead +caldrons; it is boiled in them until the greater part of the water has +evaporated. The earthy sediment deposited at the bottom of the caldron +is composed of fatty and aluminous matter, which usually consists of +small incrustations, in which there is not infrequently found a very +white and very light powder of asbestos or gypsum. The solution now +seems to be full of meal. Some people instead pour the partly evaporated +solution into a vat, so that it may become pure and clear; then pouring +it back into the caldron, they boil it again until it becomes mealy. By +whichever process it has been condensed, it is then poured into a wooden +tub sunk into the earth in order to cool it. When it becomes cold it is +poured into vats, in which are arranged horizontal and vertical twigs, +to which the alum clings when it condenses; and thus are made the small +white transparent cubes, which are laid to dry in hot rooms. + +If vitriol forms part of the aluminous ore, the material is dissolved in +water without being mixed with urine, but it is necessary to pour that +into the clear and pure solution when it is to be re-boiled. This +separates the vitriol from the alum, for by this method the latter sinks +to the bottom of the caldron, while the former floats on the top; both +must be poured separately into smaller vessels, and from these into vats +to condense. If, however, when the solution was re-boiled they did not +separate, then they must be poured from the smaller vessels into larger +vessels and covered over; then the vitriol separating from the alum, it +condenses. Both are cut out and put to dry in the hot room, and are +ready to be sold; the solution which did not congeal in the vessels +and vats is again poured back into the caldron to be re-boiled. The +earth which settled at the bottom of the caldron is carried back to the +tanks, and, together with the ore, is again dissolved with water and +urine. The earth which remains in the tanks after the solution has been +drawn off is emptied in a heap, and daily becomes more and more +aluminous in the same way as the earth from which saltpetre was made, +but fuller of its juices, wherefore it is again thrown into the tanks +and percolated by water. + +[Illustration 571 (Alum Making): A--Furnace. B--Enclosed space. +C--Aluminous rock. D--Deep ladle. E--Caldron. F--Launder. G--Troughs.] + +Aluminous rock is first roasted in a furnace similar to a lime kiln. At +the bottom of the kiln a vaulted fireplace is made of the same kind of +rock; the remainder of the empty part of the kiln is then entirely +filled with the same aluminous rocks. Then they are heated with fire +until they are red hot and have exhaled their sulphurous fumes, which +occurs, according to their divers nature, within the space of ten, +eleven, twelve, or more hours. One thing the master must guard against +most of all is not to roast the rock either too much or too little, for +on the one hand they would not soften when sprinkled with water, and on +the other they either would be too hard or would crumble into ashes; +from neither would much alum be obtained, for the strength which they +have would be decreased. When the rocks are cooled they are drawn out +and conveyed into an open space, where they are piled one upon the other +in heaps fifty feet long, eight feet wide, and four feet high, which are +sprinkled for forty days with water carried in deep ladles. In spring +the sprinkling is done both morning and evening, and in summer at noon +besides. After being moistened for this length of time the rocks begin +to fall to pieces like slaked lime, and there originates a certain new +material of the future alum, which is soft and similar to the _liquidae +medullae_ found in the rocks. It is white if the stone was white before +it was roasted, and rose-coloured if red was mixed with the white; from +the former, white alum is obtained, and from the latter, rose-coloured. +A round furnace is made, the lower part of which, in order to be able to +endure the force of the heat, is made of rock that neither melts nor +crumbles to powder by the fire. It is constructed in the form of a +basket, the walls of which are two feet high, made of the same rock. On +these walls rests a large round caldron made of copper plates, which is +concave at the bottom, where it is eight feet in diameter. In the empty +space under the bottom they place the wood to be kindled with fire. +Around the edge of the bottom of the caldron, rock is built in +cone-shaped, and the diameter of the bottom of the rock structure is +seven feet, and of the top ten feet; it is eight feet deep. The inside, +after being rubbed over with oil, is covered with cement, so that it may +be able to hold boiling water; the cement is composed of fresh lime, of +which the lumps are slaked with wine, of iron-scales, and of sea-snails, +ground and mixed with the white of eggs and oil. The edges of the +caldron are surmounted with a circle of wood a foot thick and half a +foot high, on which the workmen rest the wooden shovels with which they +cleanse the water of earth and of the undissolved lumps of rock that +remain at the bottom of the caldron. The caldron, being thus prepared, +is entirely filled through a launder with water, and this is boiled with +a fierce fire until it bubbles. Then little by little eight wheelbarrow +loads of the material, composed of roasted rock moistened with water, +are gradually emptied into the caldron by four workmen, who, with their +shovels which reach to the bottom, keep the material stirred and mixed +with water, and by the same means they lift the lumps of undissolved +rock out of the caldron. In this manner the material is thrown in, in +three or four lots, at intervals of two or three hours more or less; +during these intervals, the water, which has been cooled by the rock and +material, again begins to boil. The water, when sufficiently purified +and ready to congeal, is ladled out and run off with launders into +thirty troughs. These troughs are made of oak, holm oak, or Turkey oak; +their interior is six feet long, five feet deep, and four feet wide. In +these the water congeals and condenses into alum, in the spring in the +space of four days, and in summer in six days. Afterward the holes at +the bottom of the oak troughs being opened, the water which has not +congealed is drawn off into buckets and poured back into the caldron; or +it may be preserved in empty troughs, so that the master of the workmen, +having seen it, may order his helpers to pour it into the caldron, for +the water which is not altogether wanting in alum, is considered better +than that which has none at all. Then the alum is hewn out with a knife +or a chisel. It is thick and excellent according to the strength of the +rock, either white or pink according to the colour of the rock. The +earthy powder, which remains three to four digits thick as the residue +of the alum at the bottom of the trough is again thrown into the caldron +and boiled with fresh aluminous material. Lastly, the alum cut out is +washed, and dried, and sold. + +Alum is also made from crude pyrites and other aluminous mixtures. It is +first roasted in an enclosed area; then, after being exposed for some +months to the air in order to soften it, it is thrown into vats and +dissolved. After this the solution is poured into the leaden rectangular +pans and boiled until it condenses into alum. The pyrites and other +stones which are not mixed with alum alone, but which also contain +vitriol, as is most usually the case, are both treated in the manner +which I have already described. Finally, if metal is contained in the +pyrites and other rock, this material must be dried, and from it either +gold, silver, or copper is made in a furnace. + +Vitriol[11] can be made by four different methods; by two of these +methods from water containing vitriol; by one method from a solution of +_melanteria_, _sory_ and _chalcitis_; and by another method from earth +or stones mixed with vitriol. + +[Illustration 574 (Vitriol Making): A--Tunnel. B--Bucket. C--Pit.] + +The vitriol water is collected into pools, and if it cannot be drained +into them, it must be drawn up and carried to them in buckets by a +workman. In hot regions or in summer, it is poured into out-of-door +pits which have been dug to a certain depth, or else it is extracted +from shafts by pumps and poured into launders, through which it flows +into the pits, where it is condensed by the heat of the sun. In cold +regions and in winter these vitriol waters are boiled down with equal +parts of fresh water in rectangular leaden caldrons; then, when cold, +the mixture is poured into vats or into tanks, which Pliny calls wooden +fish-tanks. In these tanks light cross-beams are fixed to the upper +part, so that they may be stationary, and from them hang ropes stretched +with little stones; to these the contents of the thickened solutions +congeal and adhere in transparent cubes or seeds of vitriol, like +bunches of grapes. + +[Illustration 575 (Vitriol Making): A--Caldron. B--Tank. C--Cross-bars. +D--Ropes. E--Little stones.] + +By the third method vitriol is made out of _melanteria_ and _sory_. If +the mines give an abundant supply of _melanteria_ and _sory_, it is +better to reject the _chalcitis_, and especially the _misy_, for from +these the vitriol is impure, particularly from the _misy_. These +materials having been dug and thrown into the tanks, they are first +dissolved with water; then, in order to recover the pyrites from which +copper is not rarely smelted and which forms a sediment at the bottom of +the tanks, the solution is transferred to other vats, which are nine +feet wide and three feet deep. Twigs and wood which float on the surface +are lifted out with a broom made of twigs, and afterward all the +sediment settles at the bottom of this vat. The solution is poured into +a rectangular leaden caldron eight feet long, three feet wide, and the +same in depth. In this caldron it is boiled until it becomes thick and +viscous, when it is poured into a launder, through which it runs into +another leaden caldron of the same size as the one described before. +When cold, the solution is drawn off through twelve little launders, out +of which it flows into as many wooden tubs four and a half feet deep and +three feet wide. Upon these tubs are placed perforated crossbars distant +from each other from four to six digits, and from the holes hang thin +laths, which reach to the bottom, with pegs or wedges driven into them. +The vitriol adheres to these laths, and within the space of a few days +congeals into cubes, which are taken away and put into a chamber having +a sloping board floor, so that the moisture which drips from the vitriol +may flow into a tub beneath. This solution is re-boiled, as is also that +solution which was left in the twelve tubs, for, by reason of its having +become too thin and liquid, it did not congeal, and was thus not +converted into vitriol. + +[Illustration 576 (Vitriol Making): A--Wooden tub. B--Cross-bars. +C--Laths. D--Sloping floor of the chamber. E--Tub placed under it.] + +[Illustration 577 (Vitriol Making): A--Caldron. B--Moulds. C--Cakes.] + +The fourth method of making vitriol is from vitriolous earth or stones. +Such ore is at first carried and heaped up, and is then left for five or +six months exposed to the rain of spring and autumn, to the heat of +summer, and to the rime and frost of winter. It must be turned over +several times with shovels, so that the part at the bottom may be +brought to the top, and it is thus ventilated and cooled; by this means +the earth crumbles up and loosens, and the stone changes from hard to +soft. Then the ore is covered with a roof, or else it is taken away and +placed under a roof, and remains in that place six, seven, or eight +months. Afterward as large a portion as is required is thrown into a +vat, which is half-filled with water; this vat is one hundred feet +long, twenty-four feet wide, eight feet deep. It has an opening at the +bottom, so that when it is opened the dregs of the ore from which the +vitriol comes may be drawn off, and it has, at the height of one foot +from the bottom, three or four little holes, so that, when closed, the +water may be retained, and when opened the solution flows out. Thus the +ore is mixed with water, stirred with poles and left in the tank until +the earthy portions sink to the bottom and the water absorbs the juices. +Then the little holes are opened, the solution flows out of the vat, and +is caught in a vat below it; this vat is of the same length as the +other, but twelve feet wide and four feet deep. If the solution is not +sufficiently vitriolous it is mixed with fresh ore; but if it contains +enough vitriol, and yet has not exhausted all of the ore rich in +vitriol, it is well to dissolve the ore again with fresh water. As soon +as the solution becomes clear, it is poured into the rectangular leaden +caldron through launders, and is boiled until the water is evaporated. +Afterward as many thin strips of iron as the nature of the solution +requires, are thrown in, and then it is boiled again until it is thick +enough, when cold, to congeal into vitriol. Then it is poured into tanks +or vats, or any other receptacle, in which all of it that is apt to +congeal does so within two or three days. The solution which does not +congeal is either poured back into the caldron to be boiled again, or +it is put aside for dissolving the new ore, for it is far preferable to +fresh water. The solidified vitriol is hewn out, and having once more +been thrown into the caldron, is re-heated until it liquefies; when +liquid, it is poured into moulds that it may be made into cakes. If the +solution first poured out is not satisfactorily thickened, it is +condensed two or three times, and each time liquefied in the caldron and +re-poured into the moulds, in which manner pure cakes, beautiful to look +at, are made from it. + +The vitriolous pyrites, which are to be numbered among the mixtures +(_mistura_), are roasted as in the case of alum, and dissolved with +water, and the solution is boiled in leaden caldrons until it condenses +into vitriol. Both alum and vitriol are often made out of these, and it +is no wonder, for these juices are cognate, and only differ in the one +point,--that the former is less, the latter more, earthy. That pyrites +which contains metal must be smelted in the furnace. In the same manner, +from other mixtures of vitriolic and metalliferous material are made +vitriol and metal. Indeed, if ores of vitriolous pyrites abound, the +miners split small logs down the centre and cut them off in lengths as +long as the drifts and tunnels are wide, in which they lay them down +transversely; but, that they may be stable, they are laid on the ground +with the wide side down and the round side up, and they touch each other +at the bottom, but not at the top. The intermediate space is filled with +pyrites, and the same crushed are scattered over the wood, so that, +coming in or going out, the road is flat and even. Since the drifts or +tunnels drip with water, these pyrites are soaked, and from them are +freed the vitriol and cognate things. If the water ceases to drip, these +dry and harden, and then they are raised from the shafts, together with +the pyrites not yet dissolved in the water, or they are carried out from +the tunnels; then they are thrown into vats or tanks, and boiling water +having been poured over them, the vitriol is freed and the pyrites are +dissolved. This green solution is transferred to other vats or tanks, +that it may be made clear and pure; it is then boiled in the lead +caldrons until it thickens; afterward it is poured into wooden tubs, +where it condenses on rods, or reeds, or twigs, into green vitriol. + +Sulphur is made from sulphurous waters, from sulphurous ores, and from +sulphurous mixtures. These waters are poured into the leaden caldrons +and boiled until they condense into sulphur. From this latter, heated +together with iron-scales, and transferred into pots, which are +afterward covered with lute and refined sulphur, another sulphur is +made, which we call _caballinum_.[12] + +[Illustration 579 (Sulphur Making): A--Pots having spouts. B--Pots +without spouts. C--Lids.] + +The ores[13] which consist mostly of sulphur and of earth, and rarely of +other minerals, are melted in big-bellied earthenware pots. The +furnaces, which hold two of these pots, are divided into three parts; +the lowest part is a foot high, and has an opening at the front for the +draught; the top of this is covered with iron plates, which are +perforated near the edges, and these support iron rods, upon which the +firewood is placed. The middle part of the furnace is one and a half +feet high, and has a mouth in front, so that the wood may be inserted; +the top of this has rods, upon which the bottom of the pots stand. The +upper part is about two feet high, and the pots are also two feet high +and one digit thick; these have below their mouths a long, slender +spout. In order that the mouth of the pot may be covered, an earthenware +lid is made which fits into it. For every two of these pots there must +be one pot of the same size and shape, and without a spout, but having +three holes, two of which are below the mouth and receive the spouts of +the two first pots; the third hole is on the opposite side at the +bottom, and through it the sulphur flows out. In each furnace are placed +two pots with spouts, and the furnace must be covered by plates of iron +smeared over with lute two digits thick; it is thus entirely closed in, +but for two or three vent-holes through which the mouths of the pots +project. Outside of the furnace, against one side, is placed the pot +without a spout, into the two holes of which the two spouts of the other +pots penetrate, and this pot should be built in at both sides to keep it +steady. When the sulphur ore has been placed in the pots, and these +placed in the furnace, they are closely covered, and it is desirable to +smear the joint over with lute, so that the sulphur will not exhale, and +for the same reason the pot below is covered with a lid, which is also +smeared with lute. The wood having been kindled, the ores are heated +until the sulphur is exhaled, and the vapour, arising through the spout, +penetrates into the lower pot and thickens into sulphur, which falls to +the bottom like melted wax. It then flows out through the hole, which, +as I said, is at the bottom of this pot; and the workman makes it into +cakes, or thin sticks or thin pieces of wood are dipped in it. Then he +takes the burning wood and glowing charcoal from the furnace, and when +it has cooled, he opens the two pots, empties the residues, which, if +the ores were composed of sulphur and earth, resemble naturally +extinguished ashes; but if the ores consisted of sulphur and earth and +stone, or sulphur and stone only, they resemble earth completely dried +or stones well roasted. Afterward the pots are re-filled with ore, and +the whole work is repeated. + +[Illustration 581 (Sulphur Making): A--Long wall. B--High walls. C--Low +walls. D--Plates. E--Upper pots. F--Lower pots.] + +The sulphurous mixture, whether it consists of stone and sulphur only, +or of stone and sulphur and metal, may be heated in similar pots, but +with perforated bottoms. Before the furnace is constructed, against the +"second" wall of the works two lateral partitions are built seven feet +high, three feet long, one and a half feet thick, and these are distant +from each other twenty-seven feet. Between them are seven low brick +walls, that measure but two feet and the same number of digits in +height, and, like the other walls, are three feet long and one foot +thick; these little walls are at equal distances from one another, +consequently they will be two and one half feet apart. At the top, iron +bars are fixed into them, which sustain iron plates three feet long and +wide and one digit thick, so that they can bear not only the weight of +the pots, but also the fierceness of the fire. These plates have in the +middle a round hole one and a half digits wide; there must not be more +than eight of these, and upon them as many pots are placed. These pots +are perforated at the bottom, and the same number of whole pots are +placed underneath them; the former contain the mixture, and are covered +with lids; the latter contain water, and their mouths are under the +holes in the plates. After wood has been arranged round the upper pots +and ignited, the mixture being heated, red, yellow, or green sulphur +drips from it and flows down through the hole, and is caught by the pots +placed underneath the plates, and is at once cooled by the water. If the +mixture contains metal, it is reserved for smelting, and, if not, it is +thrown away. The sulphur from such a mixture can best be extracted if +the upper pots are placed in a vaulted furnace, like those which I +described among other metallurgical subjects in Book VIII., which has no +floor, but a grate inside; under this the lower pots are placed in the +same manner, but the plates must have larger holes. + +[Illustration 582 (Bitumen Making): A--Lower pot. B--Upper pot. C--Lid.] + +Others bury a pot in the ground, and place over it another pot with a +hole at the bottom, in which pyrites or _cadmia_, or other sulphurous +stones are so enclosed that the sulphur cannot exhale. A fierce fire +heats the sulphur, and it drips away and flows down into the lower pot, +which contains water. (Illustration p. 582). + +[Illustration 583 (Bitumen Making): A--Bituminous spring. B--Bucket. +C--Pot. D--Lid.] + +Bitumen[14] is made from bituminous waters, from liquid bitumen, and +from mixtures of bituminous substances. The water, bituminous as well as +salty, at Babylon, as Pliny writes, was taken from the wells to the +salt works and heated by the great heat of the sun, and condensed partly +into liquid bitumen and partly into salt. The bitumen being lighter, +floats on the top, while the salt being heavier, sinks to the bottom. +Liquid bitumen, if there is much floating on springs, streams and +rivers, is drawn up in buckets or other vessels; but, if there is +little, it is collected with goose wings, pieces of linen, _ralla_, +shreds of reeds, and other things to which it easily adheres, and it is +boiled in large brass or iron pots by fire and condensed. As this +bitumen is put to divers uses, some mix pitch with the liquid, others +old cart-grease, in order to temper its viscosity; these, however long +they are boiled in the pots, cannot be made hard. The mixtures +containing bitumen are also treated in the same manner as those +containing sulphur, in pots having a hole in the bottom, and it is rare +that such bitumen is not highly esteemed. + +[Illustration 585 (Chrysocolla Making): A--Mouth of the tunnel. +B--Trough. C--Tanks. D--Little trough.] + +Since all solidified juices and earths, if abundantly and copiously +mixed with the water, are deposited in the beds of springs, streams or +rivers, and the stones therein are coated by them, they do not require +the heat of the sun or fire to harden them. This having been pondered +over by wise men, they discovered methods by which the remainder of +these solidified juices and unusual earths can be collected. Such +waters, whether flowing from springs or tunnels, are collected in many +wooden tubs or tanks arranged in consecutive order, and deposit in them +such juices or earths; these being scraped off every year, are +collected, as _chrysocolla_[15] in the Carpathians and as ochre in the +Harz. + +There remains glass, the preparation of which belongs here, for the +reason that it is obtained by the power of fire and subtle art from +certain solidified juices and from coarse or fine sand. It is +transparent, as are certain solidified juices, gems, and stones; and can +be melted like fusible stones and metals. First I must speak of the +materials from which glass is made; then of the furnaces in which it is +melted; then of the methods by which it is produced. + +It is made from fusible stones and from solidified juices, or from other +juicy substances which are connected by a natural relationship. Stones +which are fusible, if they are white and translucent, are more excellent +than the others, for which reason crystals take the first place. From +these, when pounded, the most excellent transparent glass was made in +India, with which no other could be compared, as Pliny relates. The +second place is accorded to stones which, although not so hard as +crystal, are yet just as white and transparent. The third is given to +white stones, which are not transparent. It is necessary, however, first +of all to heat all these, and afterward they are subjected to the pestle +in order to break and crush them into coarse sand, and then they are +passed through a sieve. If this kind of coarse or fine sand is found by +the glass-makers near the mouth of a river, it saves them much labour in +burning and crushing. As regards the solidified juices, the first place +is given to soda; the second to white and translucent rock-salt; the +third to salts which are made from lye, from the ashes of the musk ivy, +or from other salty herbs. Yet there are some who give to this latter, +and not to the former, the second place. One part of coarse or fine sand +made from fusible stones should be mixed with two parts of soda or of +rock-salt or of herb salts, to which are added minute particles of +_magnes_.[16] It is true that in our day, as much as in ancient times, +there exists the belief in the singular power of the latter to attract +to itself the vitreous liquid just as it does iron, and by attracting it +to purify and transform green or yellow into white; and afterward fire +consumes the _magnes_. When the said juices are not to be had, two parts +of the ashes of oak or holmoak, or of hard oak or Turkey oak, or if +these be not available, of beech or pine, are mixed with one part of +coarse or fine sand, and a small quantity of salt is added, made from +salt water or sea-water, and a small particle of _magnes_; but these +make a less white and translucent glass. The ashes should be made from +old trees, of which the trunk at a height of six feet is hollowed out +and fire is put in, and thus the whole tree is consumed and converted +into ashes. This is done in winter when the snow lies long, or in summer +when it does not rain, for the showers at other times of the year, by +mixing the ashes with earth, render them impure; for this reason, at +such times, these same trees are cut up into many pieces and burned +under cover, and are thus converted into ashes. + +[Illustration 587 (Glass-making Furnace): A--Lower chamber of the first +furnace. B--Upper chamber. C--Vitreous mass.] + +Some glass-makers use three furnaces, others two, others only one. Those +who use three, melt the material in the first, re-melt it in the second, +and in the third they cool the glowing glass vessels and other +articles. Of these the first furnace must be vaulted and similar to an +oven. In the upper chamber, which is six feet long, four feet wide, and +two feet high, the mixed materials are heated by a fierce fire of dry +wood until they melt and are converted into a vitreous mass. And if they +are not satisfactorily purified from dross, they are taken out and +cooled and broken into pieces; and the vitreous pieces are heated in +pots in the same furnace. + +[Illustration 588 (Glass-making Furnace): A--Arches of the second +furnace. B--Mouth of the lower chamber. C--Windows of the upper chamber. +D--Big-bellied pots. E--Mouth of the third furnace. F--Recesses for the +receptacles. G--Openings in the upper chamber. H--Oblong receptacles.] + +The second furnace is round, ten feet in diameter and eight feet high, +and on the outside, so that it may be stronger, it is encompassed by +five arches, one and one half feet thick; it consists in like manner of +two chambers, of which the lower one is vaulted and is one and one half +feet thick. In front this chamber has a narrow mouth, through which the +wood can be put into the hearth, which is on the ground. At the top and +in the middle of its vault, there is a large round hole which opens to +the upper chamber, so that the flames can penetrate into it. Between the +arches in the walls of the upper chamber are eight windows, so large +that the big-bellied pots may be placed through them on to the floor of +the chamber, around the large hole. The thickness of these pots is about +two digits, their height the same number of feet, and the diameter of +the belly one and a half feet, and of the mouth and bottom one foot. In +the back part of the furnace is a rectangular hole, measuring in height +and width a palm, through which the heat penetrates into a third furnace +which adjoins it. + +This third furnace is rectangular, eight feet long and six feet wide; it +also consists of two chambers, of which the lower has a mouth in front, +so that firewood may be placed on the hearth which is on the ground. On +each side of this opening in the wall of the lower chamber is a recess +for oblong earthenware receptacles, which are about four feet long, two +feet high, and one and a half feet wide. The upper chamber has two +holes, one on the right side, the other on the left, of such height and +width that earthenware receptacles may be conveniently placed in them. +These latter receptacles are three feet long, one and a half feet high, +the lower part one foot wide, and the upper part rounded. In these +receptacles the glass articles, which have been blown, are placed so +that they may cool in a milder temperature; if they were not cooled +slowly they would burst asunder. When the vessels are taken from the +upper chamber, they are immediately placed in the receptacles to cool. + +[Illustration 589 (Glass-making Furnaces): A--Lower chamber of the +other second furnace. B--Middle one. C--Upper one. D--Its opening. +E--Round opening. F--Rectangular opening.] + +Some who use two furnaces partly melt the mixture in the first, and not +only re-melt it in the second, but also replace the glass articles +there. Others partly melt and re-melt the material in different chambers +of the second furnace. Thus the former lack the third furnace, and the +latter, the first. But this kind of second furnace differs from the +other second furnace, for it is, indeed, round, but the interior is +eight feet in diameter and twelve feet high, and it consists of three +chambers, of which the lowest is not unlike the lowest of the other +second furnace. In the middle chamber wall there are six arched +openings, in which are placed the pots to be heated, and the remainder +of the small windows are blocked up with lute. In the middle top of the +middle chamber is a square opening a palm in length and width. Through +this the heat penetrates into the upper chamber, of which the rear part +has an opening to receive the oblong earthenware receptacles, in which +are placed the glass articles to be slowly cooled. On this side, the +ground of the workshop is higher, or else a bench is placed there, so +that the glass-makers may stand upon it to stow away their products more +conveniently. + +Those who lack the first furnace in the evening, when they have +accomplished their day's work, place the material in the pots, so that +the heat during the night may melt it and turn it into glass. Two boys +alternately, during night and day, keep up the fire by throwing dry wood +on to the hearth. Those who have but one furnace use the second sort, +made with three chambers. Then in the evening they pour the material +into the pots, and in the morning, having extracted the fused material, +they make the glass objects, which they place in the upper chamber, as +do the others. + +The second furnace consists either of two or three chambers, the first +of which is made of unburnt bricks dried in the sun. These bricks are +made of a kind of clay that cannot be easily melted by fire nor resolved +into powder; this clay is cleaned of small stones and beaten with rods. +The bricks are laid with the same kind of clay instead of lime. From the +same clay the potters also make their vessels and pots, which they dry +in the shade. These two parts having been completed, there remains the +third. + +[Illustration 591 (Glass Making): A--Blow-pipe. B--Little window. +C--Marble. D--Forceps. E--Moulds by means of which the shapes are +produced.] + +The vitreous mass having been made in the first furnace in the manner I +described, is broken up, and the assistant heats the second furnace, in +order that the fragments may be re-melted. In the meantime, while they +are doing this, the pots are first warmed by a slow fire in the first +furnace, so that the vapours may evaporate, and then by a fiercer fire, +so that they become red in drying. Afterward the glass-makers open the +mouth of the furnace, and, seizing the pots with tongs, if they have not +cracked and fallen to pieces, quickly place them in the second furnace, +and they fill them up with the fragments of the heated vitreous mass or +with glass. Afterward they close up all the windows with lute and +bricks, with the exception that in each there are two little windows +left free; through one of these they inspect the glass contained in the +pot, and take it up by means of a blow-pipe; in the other they rest +another blow-pipe, so that it may get warm. Whether it is made of brass, +bronze, or iron, the blow-pipe must be three feet long. In front of +the window is inserted a lip of marble, on which rests the heaped-up +clay and the iron shield. The clay holds the blow-pipe when it is put +into the furnace, whereas the shield preserves the eyes of the +glass-maker from the fire. All this having been carried out in order, +the glass-makers bring the work to completion. The broken pieces they +re-melt with dry wood, which emits no smoke, but only a flame. The +longer they re-melt it, the purer and more transparent it becomes, the +fewer spots and blisters there are, and therefore the glass-makers can +carry out their work more easily. For this reason those who only melt +the material from which glass is made for one night, and then +immediately make it up into glass articles, make them less pure and +transparent than those who first produce a vitreous mass and then +re-melt the broken pieces again for a day and a night. And, again, these +make a less pure and transparent glass than do those who melt it again +for two days and two nights, for the excellence of the glass does not +consist solely in the material from which it is made, but also in the +melting. The glass-makers often test the glass by drawing it up with the +blowpipes; as soon as they observe that the fragments have been +re-melted and purified satisfactorily, each of them with another +blow-pipe which is in the pot, slowly stirs and takes up the glass which +sticks to it in the shape of a ball like a glutinous, coagulated gum. He +takes up just as much as he needs to complete the article he wishes to +make; then he presses it against the lip of marble and kneads it round +and round until it consolidates. When he blows through the pipe he blows +as he would if inflating a bubble; he blows into the blow-pipe as often +as it is necessary, removing it from his mouth to re-fill his cheeks, so +that his breath does not draw the flames into his mouth. Then, twisting +the lifted blow-pipe round his head in a circle, he makes a long glass, +or moulds the same in a hollow copper mould, turning it round and round, +then warming it again, blowing it and pressing it, he widens it into the +shape of a cup or vessel, or of any other object he has in mind. Then he +again presses this against the marble to flatten the bottom, which he +moulds in the interior with his other blow-pipe. Afterward he cuts out +the lip with shears, and, if necessary, adds feet and handles. If it so +please him, he gilds it and paints it with various colours. Finally, he +lays it in the oblong earthenware receptacle, which is placed in the +third furnace, or in the upper chamber of the second furnace, that it +may cool. When this receptacle is full of other slowly-cooled articles, +he passes a wide iron bar under it, and, carrying it on the left arm, +places it in another recess. + +The glass-makers make divers things, such as goblets, cups, ewers, +flasks, dishes, plates, panes of glass, animals, trees, and ships, all +of which excellent and wonderful works I have seen when I spent two +whole years in Venice some time ago. Especially at the time of the Feast +of the Ascension they were on sale at Morano, where are located the most +celebrated glass-works. These I saw on other occasions, and when, for a +certain reason, I visited Andrea Naugerio in his house which he had +there, and conversed with him and Francisco Asulano. + + END OF BOOK XII. + + +FOOTNOTES: + +[1] The history of salt-making in salt-pans, from sea-water or salt +springs, goes further back than human records. From an historical point +of view the real interest attached to salt lies in the bearing which +localities rich in either natural salt or salt springs, have had upon +the movements of the human race. Many ancient trade routes have been due +to them, and innumerable battles have been fought for their possession. +Salt has at times served for currency, and during many centuries in +nearly every country has served as a basis of taxation. These subjects +do not, however, come within the scope of this text. For the quotation +from Pliny referred to, see Note 14 below, on bitumen. + +[2] The first edition gives _graviorem_, the latter editions +_gratiorem_, which latter would have quite the reverse meaning from the +above. + +[3] The following are approximately the English equivalents:-- + + Pints. Quarts. Gallons. + 1 _Cyathus_ .08 + 3 _Cyathi_ = 1 _Quartarius_ .24 + 4 _Quartarii_ = 1 _Sextarius_ .99 + 6 _Sextarii_ = 1 _Congius_ 5.94 2.97 + 16 _Sextarii_ = 1 _Modius_ 15.85 7.93 1.98 + 8 _Congii_ = 1 _Amphora_ 47.57 23.78 5.94 + +The dipper mentioned would thus hold about one and one quarter gallons, +and the cask ten gallons. + +[4] The salt industry, founded upon salt springs, is still of importance +to this city. It was a salt centre of importance to the Germanic tribes +before Charles, the son of Charlemagne, erected a fortress here in 806. +Mention of the salt works is made in the charter by Otto I., conveying +the place to the Diocese of Magdeburg, in 968. + +[5] Pliny XXXI., 39-40. "In the Gallic provinces in Germany they pour +salt water upon burning wood. The Spaniards in a certain place draw the +brine from wells, which they call _Muria_. They indeed think that the +wood turns to salt, and that the oak is the best, being the kind which +is itself salty. Elsewhere the hazel is praised. Thus the charcoal even +is turned into salt when it is steeped in brine. Whenever salt is made +with wood it is black." + +[6] We have elsewhere in this book used the word "soda" for the Latin +term _nitrum_, because we believe as used by Agricola it was always +soda, and because some confusion of this term with its modern adaptation +for saltpetre (nitre) might arise in the mind of the reader. +Fortunately, Agricola usually carefully mentions other alkalis, such as +the product from lixiviation of ashes, separately from his _nitrum_. In +these paragraphs, however, he has soda and potash hopelessly mixed, +wherefore we have here introduced the Latin term. The actual difference +between potash and soda--the _nitrum_ of the Ancients, and the _alkali_ +of Geber (and the glossary of Agricola), was not understood for two +hundred years after Agricola, when Duhamel made his well-known +determinations; and the isolation of sodium and potassium was, of +course, still later by fifty years. If the reeds and rushes described in +this paragraph grew near the sea, the salt from lixiviation would be +soda, and likewise the Egyptian product was soda, but the lixiviation of +wood-ash produces only potash; as seen above, all are termed _nitrum_ +except the first. + +HISTORICAL NOTES.--The word _nitrum_, _nitron_, _nitri_, _neter_, +_nether_, or similar forms, occurs in innumerable ancient writings. +Among such references are Jeremiah (II., 22) Proverbs (XXV., 20), +Herodotus (II., 86, 87), Aristotle (_Prob._ I., 39, _De Mirab._ 54), +Theophrastus (_De Igne_ 435 ed. Heinsii, Hist. Plants III., 9), +Dioscorides (V., 89), Pliny (XIV., 26, and XXXI., 46). A review of +disputations on what salts this term comprised among the Ancients would +itself fill a volume, but from the properties named it was no doubt +mostly soda, more rarely potash, and sometimes both mixed with common +salt. There is every reason to believe from the properties and uses +mentioned, that it did not generally comprise nitre (saltpetre)--into +which superficial error the nomenclature has led many translators. The +preparation by way of burning, and the use of _nitrum_ for purposes for +which we now use soap, for making glass, for medicines, cosmetics, +salves, painting, in baking powder, for preserving food, embalming, +etc., and the descriptions of its taste in "nitrous" waters,--all answer +for soda and potash, but not for saltpetre. It is possible that the +common occurrence of saltpetre as an efflorescence on walls might +naturally lead to its use, but in any event its distinguishing +characteristics are nowhere mentioned. As sal-ammoniac occurred in the +volcanoes in Italy, it also may have been included in the _nitrum_ +mentioned. _Nitrum_ was in the main exported from Egypt, but +Theophrastus mentions its production from wood-ash, and Pliny very +rightly states that burned lees of wine (argol) had the nature of +_nitrum_. Many of the ancient writers understood that it was rendered +more caustic by burning, and still more so by treatment with lime. +According to Beckmann (Hist. of Inventions II., p. 488), the form of the +word _natron_ was first introduced into Europe by two travellers in +Egypt, Peter Ballon and Prosper Alpinus, about 1550. The word was +introduced into mineralogy by Linnaeus in 1736. In the first instance +_natron_ was applied to soda and potash in distinction to _nitre_ for +saltpetre, and later _natron_ was applied solely to soda. + +It is desirable to mention here two other forms of soda and potash which +are frequently mentioned by Agricola. "Ashes which wool dyers use" +(_cineres quo infectores lanarum utuntur_).--There is no indication in +any of Agricola's works as to whether this was some special wood-ash or +whether it was the calcined residues from wool washing. The "yolk" or +"suint" of wool, originating from the perspiration of the animal, has +long been a source of crude potash. The water, after washing the wool, +is evaporated, and the residue calcined. It contains about 85% +K_{2}CO_{3}, the remainder being sodium and potassium sulphates. Another +reason for assuming that it was not a wood-ash product, is that these +products are separately mentioned. In either event, whether obtained +from wool residues or from lixiviation of wood-ash, it would be an +impure potash. In some methods of wool dyeing, a wash of soda was first +given, so that it is barely possible that this substance was sodium +carbonate. + +"Salt made from the ashes of musk ivy" (_sal ex anthyllidis cinere +factus_,--Glossary, _salalkali_). This would be largely potash. + +[7] This wondrous illustration of soda-making from Nile water is no +doubt founded upon Pliny (XXXI., 46). "It is made in almost the same +manner as salt, except that sea-water is put into salt pans, whereas in +the nitrous pans it is water of the Nile; these, with the subsidence of +the Nile during the forty days, are impregnated with _nitrum_." + +[8] This paragraph displays hopeless ignorance. Borax was known to +Agricola and greatly used in his time; it certainly was not made from +these compounds, but was imported from Central Asia. Sal-ammoniac was +also known in his time, and was used like borax as a soldering agent. +The reaction given by Agricola would yield free ammonia. The following +historical notes on borax and sal-ammoniac may be of service. + +BORAX.--The uncertainties of the ancient distinctions in salts involve +borax deeply. The word _Baurach_ occurs in Geber and the other early +Alchemistic writings, but there is nothing to prove that it was modern +borax. There cannot be the slightest doubt, however, that the material +referred to by Agricola as _borax_ was our borax, because of the +characteristic qualities incidentally mentioned in Book VII. That he +believed it was an artificial product from _nitrum_ is evident enough +from his usual expression "_chrysocolla_ made from _nitrum_, which the +Moors call _borax_." Agricola, in _De Natura Fossilium_ (p. 206-7), +makes the following statements, which could leave no doubt on the +subject:--"Native _nitrum_ is found in the earth or on the surface.... +It is from this variety that the Venetians make _chrysocolla_, which I +call _borax_.... The second variety of artificial _nitrum_ is made at +the present day from the native _nitrum_, called by the Arabs _tincar_, +but I call it usually by the Greek name _chrysocolla_; it is really the +Arabic _borax_.... This _nitrum_ does not decrepitate nor fly out of the +fire; however, the native variety swells up from within." The +application of the word _chrysocolla_ (_chrysos_, gold; _colla_, solder) +to soldering materials, and at the same time to the copper mineral, is +of Greek origin. If any further proof were needed as to the substance +meant by Agricola, it lies in the word _tincar_. For a long time the +borax of Europe was imported from Central Asia, through Constantinople +and Venice, under the name of _tincal_ or _tincar_. When this trade +began, we do not know; evidently before Agricola's time. The statement +here of making borax from alum and sal-ammoniac is identical with the +assertion of Biringuccio (II., 9). + +SAL-AMMONIAC.--The early history of this--ammonium chloride--is also +under a cloud. Pliny (XXXI., 39) speaks of a _sal-hammoniacum_, and +Dioscorides (V., 85) uses much the same word. Pliny describes it as from +near the temple of Ammon in Egypt. None of the distinctive +characteristics of sal-ammoniac are mentioned, and there is every reason +to believe it was either common salt or soda. Herodotus, Strabo, and +others mention common salt sent from about the same locality. The first +authentic mention is in Geber, who calls it _sal-ammoniacum_, and +describes a method of making, and several characteristic reactions. It +was known in the Middle Ages under various names, among them +_sal-aremonicum_. Agricola (_De Nat. Fos._, III., p. 206) notes its +characteristic quality of volatilization. "Sal-ammoniac ... in the fire +neither crackles nor flies out, but is totally consumed." He also says +(p. 208): "Borax is used by goldsmiths to solder gold, likewise silver. +The artificers who make iron needles (tacks?) similarly use sal-ammoniac +when they cover the heads with tin." The statement from Pliny mentioned +in this paragraph is from XXXIII., 29, where he describes the +_chrysocolla_ used as gold solder as made from verdigris, _nitrum_, and +urine in the way quoted. It is quite possible that this solder was +sal-ammoniac, though not made in quite this manner. Pliny refers in +several places (XXXIII., 26, 27, 28, and 29, XXXV., 28, etc.) to +_chrysocolla_, about which he is greatly confused as between +gold-solder, the copper mineral, and a green pigment, the latter being +of either mineral origin. + +[9] Saltpetre was secured in the Middle Ages in two ways, but mostly +from the treatment of calcium nitrate efflorescence on cellar and +similar walls, and from so-called saltpetre plantations. In this +description of the latter, one of the most essential factors is omitted +until the last sentence, _i.e._, that the nitrous earth was the result +of the decay of organic or animal matter over a long period. Such +decomposition, in the presence of potassium and calcium carbonates--the +lye and lime--form potassium and calcium nitrates, together with some +magnesium and sodium nitrates. After lixiviation, the addition of lye +converts the calcium and magnesium nitrates into saltpetre, _i.e._, +Ca(NO_{3})_{2} + K_{2}CO_{3} = CaCO_{3} + 2KNO_{3}. The carbonates +precipitate out, leaving the saltpetre in solution, from which it was +evaporated and crystallized out. The addition of alum as mentioned would +scarcely improve the situation. + +The purification by repeated re-solution and addition of lye, and +filtration, would eliminate the remaining other salts. The purification +with sulphur, however, is more difficult to understand. In this case the +saltpetre is melted and the sulphur added and set alight. Such an +addition to saltpetre would no doubt burn brilliantly. The potassium +sulphate formed would possibly settle to the bottom, and if the "greasy +matter" were simply organic impurities, they might be burned off. This +method of refining appears to have been copied from Biringuccio (X., 1), +who states it in almost identical terms. + +HISTORICAL NOTE.--As mentioned in Note 6 above, it is quite possible +that the Ancients did include efflorescence of walls under _nitrum_; +but, so far as we are aware, no specific mention of such an occurrence +of _nitrum_ is given, and, as stated before, there is every reason to +believe that all the substances under that term were soda and potash. +Especially the frequent mention of the preparation of _nitrum_ by way of +burning, argues strongly against saltpetre being included, as they would +hardly have failed to notice the decrepitation. Argument has been put +forward that Greek fire contained saltpetre, but it amounts to nothing +more than argument, for in those receipts preserved, no salt of any kind +is mentioned. It is most likely that the leprosy of house-walls of the +Mosaic code (Leviticus XIV., 34 to 53) was saltpetre efflorescence. The +drastic treatment by way of destruction of such "unclean" walls and +houses, however, is sufficient evidence that this salt was not used. The +first certain mention of saltpetre (_sal petrae_) is in Geber. As stated +before, the date of this work is uncertain; in any event it was probably +as early as the 13th Century. He describes the making of "solvative +water" with alum and saltpetre, so there can be no doubt as to the +substance (see Note on p. 460, on nitric acid). There is also a work by +a nebulous Marcus Graecus, where the word _sal petrosum_ is used. And it +appears that Roger Bacon (died 1294) and Albertus Magnus (died 1280) +both had access to that work. Bacon uses the term _sal petrae_ +frequently enough, and was the first to describe gunpowder (_De Mirabili +Potestate Artis et Naturae_ 1242). He gives no mention of the method of +making his _sal petrae_. Agricola uses throughout the Latin text the +term _halinitrum_, a word he appears to have coined himself. However, he +gives its German equivalent in the _Interpretatio_ as _salpeter_. The +only previous description of the method of making saltpetre, of which we +are aware, is that of Biringuccio (1540), who mentions the boiling of +the excrescences from walls, and also says a good deal about boiling +solutions from "nitrous" earth, which may or may not be of "plantation" +origin. He also gives this same method of refining with sulphur. In any +event, this statement by Agricola is the first clear and complete +description of the saltpetre "plantations." Saltpetre was in great +demand in the Middle Ages for the manufacture of gunpowder, and the +first record of that substance and of explosive weapons necessarily +involves the knowledge of saltpetre. However, authentic mention of such +weapons only begins early in the 14th Century. Among the earliest is an +authority to the Council of Twelve at Florence to appoint persons to +make cannon, etc., (1326), references to cannon in the stores of the +Tower of London, 1388, &c. + +[10] There are three methods of manufacturing alum described by +Agricola, the first and third apparently from shales, and the second +from alum rock or "alunite." The reasons for assuming that the first +process was from shales, are the reference to the "aluminous earth" as +ore (_venae_) coming from "veins," and also the mixture of vitriol. In +this process the free sulphuric acid formed by the oxidation of pyrites +reacts upon the argillaceous material to form aluminium sulphate. The +decomposed ore is then placed in tanks and lixiviated. The solution +would contain aluminium sulphate, vitriol, and other impurities. By the +addition of urine, the aluminium sulphate would be converted into +ammonia alum. Agricola is, of course, mistaken as to the effect of the +addition, being under the belief that it separated the vitriol from the +alum; in fact, this belief was general until the latter part of the 18th +Century, when Lavoisier determined that alum must have an alkali base. +Nor is it clear from this description exactly how they were separated. +In a condensed solution allowed to cool, the alum would precipitate out +as "alum meal," and the vitriol would "float on top"--in solution. The +reference to "meal" may represent this phenomenon, and the re-boiling +referred to would be the normal method of purification by +crystallization. The "asbestos" and gypsum deposited in the caldrons +were no doubt feathery and mealy calcium sulphate. The alum produced +would, in any event, be mostly ammonia alum. + +The second process is certainly the manufacture from "alum rock" or +"alunite" (the hydrous sulphate of aluminium and potassium), such as +that mined at La Tolfa in the Papal States, where the process has been +for centuries identical with that here described. The alum there +produced is the double basic potassium alum, and crystallizes into cubes +instead of octahedra, _i.e._, the Roman alum of commerce. The presence +of much ferric oxide gives the rose colour referred to by Agricola. This +account is almost identical with that of Biringuccio (II., 4), and it +appears from similarity of details that Agricola, as stated in his +preface, must have "refreshed his mind" from this description; it would +also appear from the preface that he had himself visited the locality. + +The third process is essentially the same as the first, except that the +decomposition of the pyrites was hastened by roasting. The following +obscure statement of some interest occurs in Agricola's _De Natura +Fossilium_, p. 209:--"... alum is made from vitriol, for when oil is +made from the latter, alum is distilled out (_expirat_). This absorbs +the clay which is used in cementing glass, and when the operation is +complete the clay is macerated with pure water, and the alum is soon +afterward deposited in the shape of small cubes." Assuming the oil of +vitriol to be sulphuric acid and the clay "used in cementing glass" to +be kaolin, we have here the first suggestion of a method for producing +alum which came into use long after. + +"Burnt alum" (_alumen coctum_).--Agricola frequently uses this +expression, and on p. 568, describes the operation, and the substance is +apparently the same as modern dehydrated alum, often referred to as +"burnt alum." + +HISTORICAL NOTES.--Whether the Ancients knew of alum in the modern sense +is a most vexed question. The Greeks refer to a certain substance as +_stypteria_, and the Romans refer to this same substance as _alumen_. +There can be no question as to their knowledge and common use of +vitriol, nor that substances which they believed were entirely different +from vitriol were comprised under the above names. Beckmann (Hist. of +Inventions, Vol. I., p. 181) seems to have been the founder of the +doctrine that the ancient _alumen_ was vitriol, and scores of +authorities seem to have adopted his arguments without inquiry, until +that belief is now general. One of the strongest reasons put forward was +that alum does not occur native in appreciable quantities. Apart from +the fact that the weight of this argument has been lost by the discovery +that alum does occur in nature to some extent as an aftermath of +volcanic action, and as an efflorescence from argillaceous rocks, we see +no reason why the Ancients may not have prepared it artificially. One of +the earliest mentions of such a substance is by Herodotus (II., 180) of +a thousand talents of _stypteria_, sent by Amasis from Egypt as a +contribution to the rebuilding of the temple of Delphi. Diodorus (V., 1) +mentions the abundance which was secured from the Lipari Islands +(Stromboli, etc.), and a small quantity from the Isle of Melos. +Dioscorides (V., 82) mentions Egypt, Lipari Islands, Melos, Sardinia, +Armenia, etc., "and generally in any other places where one finds red +ochre (_rubrica_)." Pliny (XXXV., 52) gives these same localities, and +is more explicit as to how it originates--"from an earthy water which +exudes from the earth." Of these localities, the Lipari Islands +(Stromboli, etc.), and Melos are volcanic enough, and both Lipari and +Melos are now known to produce natural alum (Dana. Syst. Min., p. 95; +and Tournefort, "_Relation d'un voyage du Levant_." London, 1717, +_Lettre_ IV., Vol. 1.). Further, the hair-like alum of Dioscorides, +repeated by Pliny below, was quite conceivably fibrous _kalinite_, +native potash alum, which occurs commonly as an efflorescence. Be the +question of native alum as it may--and vitriol is not much more +common--our own view that the ancient _alumen_ was alum, is equally +based upon the artificial product. Before entering upon the subject, we +consider it desirable to set out the properties of the ancient +substance, a complete review of which is given by Pliny (XXXV., 52), he +obviously quoting also from Dioscorides, which, therefore, we do not +need to reproduce. Pliny says:-- + +"Not less important, or indeed dissimilar, are the uses made of +_alumen_; by which name is understood a sort of salty earth. Of this, +there are several kinds. In Cyprus there is a white _alumen_, and a +darker kind. There is not a great difference in their colour, though the +uses made of them are very dissimilar,--the white _alumen_ being +employed in a liquid state for dyeing wool bright colours, and the +dark-coloured _alumen_, on the other hand, for giving wool a sombre +tint. Gold is purified with black _alumen_. Every kind of _alumen_ is +from a _limus_ water which exudes from the earth. The collection of it +commences in winter, and it is dried by the summer sun. That portion of +it which first matures is the whitest. It is obtained in Spain, Egypt, +Armenia, Macedonia, Pontus, Africa, and the islands of Sardinia, Melos, +Lipari, and Strongyle; the most esteemed, however, is that of Egypt, the +next best from Melos. Of this last there are two kinds, the liquid +_alumen_, and the solid. Liquid _alumen_, to be good, should be of a +limpid and milky appearance; when rubbed, it should be without +roughness, and should give a little heat. This is called _phorimon_. The +mode of detecting whether it has been adulterated is by pomegranate +juice, for, if genuine, the mixture turns black. The other, or solid, is +pale and rough and turns dark with nut-galls; for which reason it is +called _paraphoron_. Liquid _alumen_ is naturally astringent, +indurative, and corrosive; used in combination with honey, it heals +ulcerations.... There is one kind of solid _alumen_, called by the +Greeks _schistos_, which splits into filaments of a whitish colour; for +which reason some prefer calling it _trichitis_ (hair like). _Alumen_ is +produced from the stone _chalcitis_, from which copper is also made, +being a sort of coagulated scum from that stone. This kind of _alumen_ +is less astringent than the others, and is less useful as a check upon +bad humours of the body.... The mode of preparing it is to cook it in a +pan until it has ceased being a liquid. There is another variety of +_alumen_ also, of a less active nature, called _strongyle_. It is of two +kinds. The fungous, which easily dissolves, is utterly condemned. The +better kind is the pumice-like kind, full of small holes like a sponge, +and is in round pieces, more nearly white in colour, somewhat greasy, +free from grit, friable, and does not stain black. This last kind is +cooked by itself upon charcoal until it is reduced to pure ashes. The +best kind of all is that called _melinum_, from the Isle of Melos, as I +have said, none being more effectual as an astringent, for staining +black, and for indurating, and none becomes more dry.... Above all other +properties of _alumen_ is its remarkable astringency, whence its Greek +name.... It is injected for dysentry and employed as a gargle." The +lines omitted refer entirely to medical matters which have no bearing +here. The following paragraph (often overlooked) from Pliny (XXXV., 42) +also has an important bearing upon the subject:--"In Egypt they employ a +wonderful method of dyeing. The white cloth, after it is pressed, is +stained in various places, not with dye stuffs, but with substances +which absorb colours. These applications are not apparent on the cloth, +but when it is immersed in a caldron of hot dye it is removed the next +moment brightly coloured. The remarkable circumstance is that although +there be only one dye in the caldron yet different colours appear in the +cloth." + +It is obvious from Pliny's description above, and also from the making +of vitriol (see Note 11, p. 572), that this substance was obtained from +liquor resulting from natural or artificial lixiviation of rocks--in the +case of vitriols undoubtedly the result of decomposition of pyritiferous +rocks (such as _chalcitis_). Such liquors are bound to contain aluminum +sulphate if there is any earth or clay about, and whether they contained +alum would be a question of an alkali being present. If no alkali were +present in this liquor, vitriol would crystallize out first, and +subsequent condensation would yield aluminum sulphate. If alkali were +present, the alum would crystallize out either before or with the +vitriol. Pliny's remark, "that portion of it which first matures is +whitest", agrees well enough with this hypothesis. No one will doubt +that some of the properties mentioned above belong peculiarly to +vitriol, but equally convincing are properties and uses that belong to +alum alone. The strongly astringent taste, white colour, and injection +for dysentry, are more peculiar to alum than to vitriol. But above all +other properties is that displayed in dyeing, for certainly if we read +this last quotation from Pliny in conjunction with the statement that +white _alumen_ produces bright colours and the dark kind, sombre +colours, we have the exact reactions of alum and vitriol when used as +mordants. Therefore, our view is that the ancient salt of this character +was a more or less impure mixture ranging from alum to vitriol--"the +whiter the better." Further, considering the ancient knowledge of soda +(_nitrum_), and the habit of mixing it into almost everything, it does +not require much flight of imagination to conceive its admixture to the +"water," and the absolute production of alum. + +Whatever may have been the confusion between alum and vitriol among the +Ancients, it appears that by the time of the works attributed to Geber +(12th or 13th Century), the difference was well known. His work +(_Investigationes perfectiones_, IV.) refers to _alumen glaciale_ and +_alumen jameni_ as distinguished from vitriol, and gives characteristic +reactions which can leave no doubt as to the distinction. We may remark +here that the repeated statement apparently arising from Meyer (History +of Chemistry, p. 51) that Geber used the term _alum de rocca_ is untrue, +this term not appearing in the early Latin translations. During the 15th +Century alum did come to be known in Europe as _alum de rocca_. Various +attempts have been made to explain the origin of this term, ranging from +the Italian root, a "rock," to the town of Rocca in Syria, where alum +was supposed to have been produced. In any event, the supply for a long +period prior to the middle of the 15th Century came from Turkey, and the +origin of the methods of manufacture described by Agricola, and used +down to the present day, must have come from the Orient. + +In the early part of the 15th Century, a large trade in alum was done +between Italy and Asia Minor, and eventually various Italians +established themselves near Constantinople and Smyrna for its +manufacture (Dudae, _Historia Byzantina Venetia_, 1729, p. 71). The alum +was secured by burning the rock, and lixiviation. With the capture of +Constantinople by the Turks (1453), great feeling grew up in Italy over +the necessity of buying this requisite for their dyeing establishments +from the infidel, and considerable exertion was made to find other +sources of supply. Some minor works were attempted, but nothing much +eventuated until the appearance of one John de Castro. From the +Commentaries of Pope Pius II. (1614, p. 185), it appears that this +Italian had been engaged in dyeing cloth in Constantinople, and thus +became aware of the methods of making alum. Driven out of that city +through its capture by the Turks, he returned to Italy and obtained an +office under the Apostolic Chamber. While in this occupation he +discovered a rock at Tolfa which appeared to him identical with that +used at Constantinople in alum manufacture. After experimental work, he +sought the aid of the Pope, which he obtained after much vicissitude. +Experts were sent, who after examination "shed tears of joy, they +kneeling down three times, worshipped God and praised His kindness in +conferring such a gift on their age." Castro was rewarded, and the great +papal monopoly was gradually built upon this discovery. The industry +firmly established at Tolfa exists to the present day, and is the source +of the Roman alum of commerce. The Pope maintained this monopoly +strenuously, by fair means and by excommunication, gradually advancing +the price until the consumers had greater complaint than against the +Turks. The history of the disputes arising over the papal alum monopoly +would alone fill a volume. + +By the middle of the 15th Century alum was being made in Spain, Holland, +and Germany, and later in England. In her efforts to encourage home +industries and escape the tribute to the Pope, Elizabeth (see Note on p. +283) invited over "certain foreign chymistes and mineral masters" and +gave them special grants to induce them to "settle in these realmes." +Among them was Cornelius Devoz, to whom was granted the privilege of +"mining and digging in our Realm of England for allom and copperas." +What Devoz accomplished is not recorded, but the first alum manufacture +on a considerable scale seems to have been in Yorkshire, by one Thomas +Chaloner (about 1608), who was supposed to have seduced workmen from the +Pope's alum works at Tolfa, for which he was duly cursed with all the +weight of the Pope and Church. (Pennant, Tour of Scotland, 1786). + +[11] The term for vitriol used by the Roman authors, followed by +Agricola, is _atramentum sutorium_, literally shoemaker's blacking, the +term no doubt arising from its ancient (and modern) use for blackening +leather. The Greek term was _chalcanthon_. The term "vitriol" seems +first to appear in Albertus Magnus (_De Mineralibus_, _Liber_ V.), who +died in 1280, where he uses the expression "_atramentum viride a +quibusdam vitreolum vocatur_." Agricola (_De Nat. Foss._, p. 213) +states, "In recent years the name _vitriolum_ has been given to it." The +first adequate description of vitriol is by Dioscorides (V., 76), as +follows:--"Vitriol (_chalcanthon_) is of one genus, and is a solidified +liquid, but it has three different species. One is formed from the +liquids which trickle down drop by drop and congeal in certain mines; +therefore those who work in the Cyprian mines call it _stalactis_. +Petesius calls this kind _pinarion_. The second kind is that which +collects in certain caverns; afterward it is poured into trenches, where +it congeals, whence it derives its name _pectos_. The third kind is +called _hephthon_ and is mostly made in Spain; it has a beautiful colour +but is weak. The manner of preparing it is as follows: dissolving it in +water, they boil it, and then they transfer it to cisterns and leave it +to settle. After a certain number of days it congeals and separates into +many small pieces, having the form of dice, which stick together like +grapes. The most valued is blue, heavy, dense, and translucent." Pliny +(XXXIV., 32) says:--"By the name which they have given to it, the Greeks +indicate the similar nature of copper and _atramentum sutorium_, for +they call it _chalcanthon_. There is no substance of an equally +miraculous nature. It is made in Spain from wells of this kind of water. +This water is boiled with an equal quantity of pure water, and is then +poured into wooden tanks (fish ponds). Across these tanks there are +fixed beams, to which hang cords stretched by little stones. Upon these +cords adheres the _limus_ (Agricola's 'juice') in drops of a vitreous +appearance, somewhat resembling a bunch of grapes. After removal, it is +dried for thirty days. It is of a blue colour, and of a brilliant +lustre, and is very like glass. Its solution is the blacking used for +colouring leather. _Chalcanthon_ is made in many other ways: its kind of +earth is sometimes dug from ditches, from the sides of which exude +drops, which solidify by the winter frosts into icicles, called +_stalagmia_, and there is none more pure. When its colour is nearly +white, with a slight tinge of violet, it is called _leukoïon_. It is +also made in rock basins, the rain water collecting the _limus_ into +them, where it becomes hardened. It is also made in the same way as salt +by the intense heat of the sun. Hence it is that some distinguish two +kinds, the mineral and the artificial; the latter being paler than the +former and as much inferior to it in quality as it is in colour." + +While Pliny gives prominence to blue vitriol, his solution for colouring +leather must have been the iron sulphate. There can be no doubt from the +above, however, that both iron and copper sulphates were known to the +Ancients. From the methods for making vitriol given here in _De Re +Metallica_, it is evident that only the iron sulphate would be produced, +for the introduction of iron strips into the vats would effectually +precipitate any copper. It is our belief that generally throughout this +work, the iron sulphate is meant by the term _atramentum sutorium_. In +_De Natura Fossilium_ (p. 213-15) Agricola gives three varieties of +_atramentum sutorium_,--_viride_, _caeruleum_, and _candidum_, _i.e._, +green, blue, and white. Thus the first mention of white vitriol (zinc +sulphate) appears to be due to him, and he states further (p. 213): "A +white sort is found, especially at Goslar, in the shape of icicles, +transparent like crystals." And on p. 215: "Since I have explained the +nature of vitriol and its relatives, which are obtained from cupriferous +pyrites, I will next speak of an acrid solidified juice which commonly +comes from _cadmia_. It is found at Annaberg in the tunnel driven to the +Saint Otto mine; it is hard and white, and so acrid that it kills mice, +crickets, and every kind of animal. However, that feathery substance +which oozes out from the mountain rocks and the thick substance found +hanging in tunnels and caves from which saltpetre is made, while +frequently acrid, does not come from _cadmia_." Dana (Syst. of Min., p. +939) identifies this as _Goslarite_--native zinc sulphate. It does not +appear, however, that artificial zinc vitriol was made in Agricola's +time. Schlüter (_Huette-Werken_, Braunschweig 1738, p. 597) states it to +have been made for the first time at Rammelsberg about 1570. + +It is desirable here to enquire into the nature of the substances given +by all of the old mineralogists under the Latinized Greek terms +_chalcitis_, _misy_, _sory_, and _melanteria_. The first mention of +these minerals is in Dioscorides, who (V., 75-77) says: "The best +_chalcitis_ is like copper. It is friable, not stony, and is intersected +by long brilliant veins.... _Misy_ is obtained from Cyprus; it should +have the appearance of gold, be hard, and when pulverised it should have +the colour of gold and sparkle like stars. It has the same properties as +_chalcitis_.... The best is from Egypt.... One kind of _melanteria_ +congeals like salt in the entries to copper mines. The other kind is +earthy and appears on the surface of the aforesaid mines. It is found in +the mines of Cilicia and other regions. The best has the colour of +sulphur, is smooth, pure, homogenous, and upon contact with water +immediately becomes black.... Those who consider _sory_ to be the same +as _melanteria_, err greatly. _Sory_ is a species of its own, though it +is not dissimilar. The smell of _sory_ is oppressive and provokes +nausea. It is found in Egypt and in other regions, as Libya, Spain, and +Cyprus. The best is from Egypt, and when broken is black, porous, +greasy, and astringent." Pliny (XXXIV., 29-31) says:--"That is called +_chalcitis_ from which, as well as itself copper (?) is extracted by +heat. It differs from _cadmia_ in that this is obtained from rocks near +the surface, while that is taken from rocks below the surface. Also +_chalcitis_ is immediately friable, being naturally so soft as to appear +like compressed wool. There is also this other distinction; _chalcitis_ +contains three other substances, copper, _misy_, and _sory_. Of each of +these we shall speak in their appropriate places. It contains elongated +copper veins. The most approved kind is of the colour of honey; it is +streaked with fine sinuous veins and is friable and not stony. It is +considered most valuable when fresh.... The _sory_ of Egypt is the most +esteemed, being much superior to that of Cyprus, Spain, and Africa; +although some prefer the _sory_ from Cyprus for affections of the eyes. +But from whatever nation it comes, the best is that which has the +strongest odour, and which, when ground up, becomes greasy, black, and +spongy. It is a substance so unpleasant to the stomach that some persons +are nauseated by its smell. Some say that _misy_ is made by the burning +of stones in trenches, its fine yellow powder being mixed with the ashes +of pine-wood. The truth is, as I said above, that though obtained from +the stone, it is already made and in solid masses, which require force +to detach them. The best comes from the works of Cyprus, its +characteristics being that when broken it sparkles like gold, and when +ground it presents a sandy appearance, but on the contrary, if heated, +it is similar to _chalcitis_. _Misy_ is used in refining gold...." + +Agricola's views on the subject appear in _De Natura Fossilium_. He says +(p. 212):--"The cupriferous pyrites (_pyrites aerosus_) called +_chalcitis_ is the mother and cause of _sory_--which is likewise known +as mine _vitriol_ (_atramentum metallicum_)--and _melanteria_. These in +turn yield vitriol and such related things. This may be seen especially +at Goslar, where the nodular lumps of dark grey colour are called +vitriol stone (_lapis atramenti_). In the centre of them is found +greyish pyrites, almost dissolved, the size of a walnut. It is enclosed +on all sides, sometimes by _sory_, sometimes by _melanteria_. From them +start little veinlets of greenish vitriol which spread all over it, +presenting somewhat the appearance of hairs extending in all directions +and cohering together.... There are five species of this solidified +juice, _melanteria_, _sory_, _chalcitis_, _misy_, and vitriol. Sometimes +many are found in one place, sometimes all of them, for one originates +from the other. From pyrites, which is, as one might say, the root of +all these juices, originates the above-mentioned _sory_ and +_melanteria_. From _sory_, _chalcitis_, and _melanteria_ originate the +various kinds of vitriol.... _Sory_, _melanteria_, _chalcitis_, and +_misy_ are always native; vitriol alone is either native or artificial. +From them vitriol effloresces white, and sometimes green or blue. _Misy_ +effloresces not only from _sory_, _melanteria_, and _chalcitis_, but +also from all the vitriols, artificial as well as natural.... _Sory_ and +_melanteria_ differ somewhat from the others, but they are of the same +colours, grey and black; but _chalcitis_ is red and copper-coloured; +_misy_ is yellow or gold-coloured. All these native varieties have the +odour of lightning (brimstone), but _sory_ is the most powerful. The +feathery vitriol is soft and fine and hair-like, and _melanteria_ has +the appearance of wool and it has a similarity to salt; all these are +rare and light; _sory_, _chalcitis_, and _misy_ have the following +relations. _Sory_ because of its density has the hardness of stone, +although its texture is very coarse. _Misy_ has a very fine texture. +_Chalcitis_ is between the two; because of its roughness and strong +odour it differs from _melanteria_, although they do not differ in +colour. The vitriols, whether natural or artificial, are hard and dense +... as regarding shape, _sory_, _chalcitis_, _misy_, and _melanteria_ +are nodular, but _sory_ is occasionally porous, which is peculiar to it. +_Misy_ when it effloresces in no great quantity from the others is like +a kind of pollen, otherwise it is nodular. _Melanteria_ sometimes +resembles wool, sometimes salt." + +The sum and substance, therefore, appears to be that _misy_ is a +yellowish material, possibly ochre, and _sory_ a blackish stone, both +impregnated with vitriol. _Chalcitis_ is a partially decomposed pyrites; +and _melanteria_ is no doubt native vitriol. From this last term comes +the modern _melanterite_, native hydrous ferrous sulphate. Dana (System +of Mineralogy, p. 964) considers _misy_ to be in part _copiapite_--basic +ferric sulphate--but any such part would not come under Agricola's +objection to it as a source of vitriol. The disabilities of this and +_chalcitis_ may, however, be due to their copper content. + +[12] Agricola (_De Nat. Fos._, 221) says:--"There is a species of +artificial sulphur made from sulphur and iron hammer-scales, melted +together and poured into moulds. This, because it heals scabs of horses, +is generally called _caballinum_." It is difficult to believe such a +combination was other than iron sulphide, but it is equally difficult to +understand how it was serviceable for this purpose. + +[13] Inasmuch as pyrites is discussed in the next paragraph, the +material of the first distillation appears to be native sulphur. Until +the receiving pots became heated above the melting point of the sulphur, +the product would be "flowers of sulphur," and not the wax-like product. +The equipment described for pyrites in the next paragraph would be +obviously useful only for coarse material. + +But little can be said on the history of sulphur; it is mentioned often +enough in the Bible and also by Homer (Od. XXII., 481). The Greeks +apparently knew how to refine it, although neither Dioscorides nor Pliny +specifically describes such an operation. Agricola says (_De Nat. Fos._, +220): "Sulphur is of two kinds; the mineral, which the Latins call +_vivum_, and the Greeks _apyron_, which means 'not exposed to the fire' +(_ignem non expertum_) as rightly interpreted by Celsius; and the +artificial, called by the Greeks _pepyromenon_, that is, 'exposed to the +fire.'" In Book X., the expression _sulfur ignem non expertum_ +frequently appears, no doubt in Agricola's mind for native sulphur, +although it is quite possible that the Greek distinction was between +"flowers" of sulphur and the "wax-like" variety. + +[14] The substances referred to under the names _bitumen_, _asphalt_, +_maltha_, _naphtha_, _petroleum_, _rock-oil_, etc., have been known and +used from most ancient times, and much of our modern nomenclature is of +actual Greek and Roman ancestry. These peoples distinguished three +related substances,--the Greek _asphaltos_ and Roman _bitumen_ for the +hard material,--Greek _pissasphaltos_ and Roman _maltha_ for the +viscous, pitchy variety--and occasionally the Greek _naphtha_ and Roman +_naphtha_ for petroleum proper, although it is often enough referred to +as liquid _bitumen_ or liquid _asphaltos_. The term _petroleum_ +apparently first appears in Agricola's _De Natura Fossilium_ (p. 222), +where he says the "oil of bitumen ... now called _petroleum_." Bitumen +was used by the Egyptians for embalming from pre-historic times, _i.e._, +prior to 5000 B.C., the term "mummy" arising from the Persian word for +bitumen, _mumiai_. It is mentioned in the tribute from Babylonia to +Thotmes III., who lived about 1500 B.C. (Wilkinson, Ancient Egyptians +I., p. 397). The Egyptians, however, did not need to go further afield +than the Sinai Peninsula for abundant supplies. Bitumen is often cited +as the real meaning of the "slime" mentioned in Genesis (XI., 3; XIV., +10), and used in building the Tower of Babel. There is no particular +reason for this assumption, except the general association of Babel, +Babylon, and Bitumen. However, the Hebrew word _sift_ for pitch or +bitumen does occur as the cement used for Moses's bulrush cradle (Exodus +II., 3), and Moses is generally accounted about 1300 B.C. Other attempts +to connect Biblical reference to petroleum and bitumen revolve around +Job XXIX., 6, Deut. XXXII., 13, Maccabees II., I, 18, Matthew V., 13, +but all require an unnecessary strain on the imagination. + +The plentiful occurrence of bitumen throughout Asia Minor, and +particularly in the Valley of the Euphrates and in Persia, is the +subject of innumerable references by writers from Herodotus (484-424 +B.C.) down to the author of the company prospectus of recent months. +Herodotus (I., 179) and Diodorus Siculus (I) state that the walls of +Babylon were mortared with bitumen--a fact partially corroborated by +modern investigation. The following statement by Herodotus (VI., 119) is +probably the source from which Pliny drew the information which Agricola +quotes above. In referring to a well at Ardericca, a place about 40 +miles from ancient Susa, in Persia, Herodotus says:--"For from the well +they get bitumen, salt, and oil, procuring it in the way that I will now +describe: they draw with a swipe, and instead of a bucket they make use +of the half of a wine-skin; with this the man dips and, after drawing, +pours the liquid into a reservoir, wherefrom it passes into another, and +there takes three different shapes. The salt and bitumen forthwith +collect and harden, while the oil is drawn off into casks. It is called +by the Persians _rhadinace_, is black, and has an unpleasant smell." +(Rawlinson's Trans. III., p. 409). The statement from Pliny (XXXI., 39) +here referred to by Agricola, reads:--"It (salt) is made from water of +wells poured into salt-pans. At Babylon the first condensed is a +bituminous liquid like oil which is burned in lamps. When this is taken +off, salt is found beneath. In Cappadocia also the water from both wells +and springs is poured into salt-pans." When petroleum began to be used +as an illuminant it is impossible to say. A passage in Aristotle's _De +Mirabilibus_ (127) is often quoted, but in reality it refers only to a +burning spring, a phenomenon noted by many writers, but from which to +its practical use is not a great step. The first really definite +statement as to the use of petroleum as an illuminant is Strabo's +quotation (XVI., 1, 15) from Posidonius: "Asphaltus is found in great +abundance in Babylonia. Eratosthenes describes it as follows:--The +liquid _asphaltus_, which is called _naphtha_, is found in Susa; the dry +kind, which can be made solid, in Babylonia. There is a spring of it +near the Euphrates.... Others say that the liquid kind is also found in +Babylonia.... The liquid kind, called _naphtha_, is of a singular +nature. When it is brought near the fire, the fire catches it.... +Posidonius says that there are springs of _naphtha_ in Babylonia, some +of which produce white, others black _naphtha_; the first of these, I +mean white _naphtha_, which attracts flame, is liquid sulphur; the +second or black _naphtha_ is liquid _asphaltus_, and is burnt in lamps +instead of oil." (Hamilton's Translation, Vol. III., p. 151). +Eratosthenes lived about 200 B.C., and Posidonius about 100 years later. +Dioscorides (I., 83), after discussing the usual sources of bitumen +says: "It is found in a liquid state in Agrigentum in Sicily, flowing on +streams; they use it for lights in lanterns in place of oil. Those who +call the Sicilian kind oil are under a delusion, for it is agreed that +it is a kind of liquid bitumen." Pliny adds nothing much new to the +above quotations, except in regard to these same springs (XXXV., 51) +that "The inhabitants collect it on the panicles of reeds, to which it +quickly adheres and they use it for burning in lamps instead of oil." +Agricola (_De Natura Fossilium_, Book IV.) classifies petroleum, coal, +jet, and obsidian, camphor, and amber as varieties of bitumen, and +devotes much space to the refutation of the claims that the last two are +of vegetable origin. + +[15] Agricola (_De Natura Fossilium_, p. 215) in discussing substances +which originate from copper, gives among them green _chrysocolla_ (as +distinguished from borax, etc., see Note 8 above), and says: "Native +_chrysocolla_ originates in veins and veinlets, and is found mostly by +itself like sand, or adhering to metallic substances, and when scraped +off from this appears similar to its own sand. Occasionally it is so +thin that very little can be scraped off. Or else it occurs in waters +which, as I have said, wash these minerals, and afterward it settles as +a powder. At Neusohl in the Carpathians, green water flowing from an +ancient tunnel wears away this _chrysocolla_ with it. The water is +collected in thirty large reservoirs, where it deposits the +_chrysocolla_ as a sediment, which they collect every year and +sell,"--as a pigment. This description of its occurrence would apply +equally well to modern _chrysocolla_ or to malachite. The solution from +copper ores would deposit some sort of green incrustation, of carbonates +mostly. + +[16] The statement in Pliny (XXXVI., 66) to which Agricola refers is as +follows: "Then as ingenuity was not content with the mixing of _nitrum_, +they began the addition of _lapis magnes_, because of the belief that it +attracts liquefied glass as well as iron. In a similar manner many kinds +of brilliant stones began to be added to the melting, and then shells +and fossil sand. Authors tell us that the glass of India is made of +broken crystal, and in consequence nothing can compare with it. Light +and dry wood is used for fusing, _cyprium_ (copper?) and _nitrum_ being +added, particularly _nitrum_ from Ophir etc." + +A great deal of discussion has arisen over this passage, in connection +with what this _lapis magnes_ really was. Pliny (XXXVI., 25) describes +the lodestone under this term, but also says: "There (in Ethiopia) also +is _haematites magnes_, a stone of blood colour, which shows a red +colour if crushed, or of saffron. The _haematites_ has not the same +property of attracting iron as _magnes_." Relying upon this sentence for +an exception to the ordinary sort of _magnes_, and upon the impossible +chemical reaction involved, most commentators have endeavoured to show +that lodestone was not the substance meant by Pliny, but manganese, and +thus they find here the first knowledge of this mineral. There can be +little doubt that Pliny assumed it to be the lodestone, and Agricola +also. Whether the latter had any independent knowledge on this point in +glass-making or was merely quoting Pliny--which seems probable--we do +not know. In any event, Biringuccio, whose work preceded _De Re +Metallica_ by fifteen years, does definitely mention manganese in this +connection. He dismisses this statement of Pliny with the remark (p. +37-38): "The Ancients wrote about lodestones, as Pliny states, and they +mixed it together with _nitrum_ in their first efforts to make glass." +The following passage from this author (p. 36-37), however, is not only +of interest in this connection, but also as possibly being the first +specific mention of manganese under its own name. Moreover, it has been +generally overlooked in the many discussions of the subject. "Of a +similar nature (to _zaffir_) is also another mineral called _manganese_, +which is found, besides in Germany, at the mountain of Viterbo in +Tuscany ... it is the colour of _ferrigno scuro_ (iron slag?). In +melting it one cannot obtain any metal ... but it gives a very fine +colour to glass, so that the glass workers use it in their pigments to +secure an azure colour.... It also has such a property that when put +into melted glass it cleanses it and makes it white, even if it were +green or yellow. In a hot fire it goes off in a vapour like lead, and +turns into ashes." + +To enter competently into the discussion of the early history of +glass-making would employ more space than can be given, and would lead +but to a sterile end. It is certain that the art was pre-Grecian, and +that the Egyptians were possessed of some knowledge of making and +blowing it in the XI Dynasty (according to Petrie 3,500 B.C.), the wall +painting at Beni Hassen, which represents glass-blowing, being +attributed to that period. The remains of a glass factory at Tel el +Amarna are believed to be of the XVIII Dynasty. (Petrie, 1,500 B.C.). +The art reached a very high state of development among the Greeks and +Romans. No discussion of this subject omits Pliny's well-known story +(XXXVI, 65), which we also add: "The tradition is that a merchant ship +laden with _nitrum_ being moored at this place, the merchants were +preparing their meal on the beach, and not having stones to prop up +their pots, they used lumps of _nitrum_ from the ship, which fused and +mixed with the sands of the shore, and there flowed streams of a new +translucent liquid, and thus was the origin of glass." + + + + +APPENDIX A. + + +AGRICOLA'S WORKS. + +Georgius Agricola was not only the author of works on Mining and allied +subjects, usually associated with his name, but he also interested +himself to some extent in political and religious subjects. For +convenience in discussion we may, therefore, divide his writings on the +broad lines of (1) works on mining, geology, mineralogy, and allied +subjects; (2) works on other subjects, medical, religious, critical, +political, and historical. In respect especially to the first division, +and partially with regard to the others, we find three principal cases: +(_a_) Works which can be authenticated in European libraries to-day; +(_b_) references to editions of these in bibliographies, catalogues, +etc., which we have been unable to authenticate; and (_c_) references to +works either unpublished or lost. The following are the short titles of +all of the published works which we have been able to find on the +subjects allied to mining, arranged according to their present +importance:--_De Re Metallica_, first edition, 1556; _De Natura +Fossilium_, first edition, 1546; _De Ortu et Causis Subterraneorum_, +first edition, 1546; _Bermannus_, first edition, 1530; _Rerum +Metallicarum Interpretatio_, first edition, 1546; _De Mensuris et +Ponderibus_, first edition, 1533; _De Precio Metallorum et Monetis_, +first edition, 1550; _De Veteribus et Novis Metallis_, first edition, +1546; _De Natura eorum quae Effluunt ex Terra_, first edition, 1546; _De +Animantibus Subterraneis_, first edition, 1549. + +Of the "lost" or unpublished works, on which there is some evidence, the +following are the most important:--_De Metallicis et Machinis_, _De Ortu +Metallorum Defensio ad Jacobum Scheckium_, _De Jure et Legibus +Metallicis_, _De Varia Temperie sive Constitutione Aeris_, _De Terrae +Motu_, and _Commentariorum, Libri VI_. + +The known published works upon other subjects are as follows:--Latin +Grammar, first edition, 1520; Two Religious Tracts, first edition, 1522; +_Galen_ (Joint Revision of Greek Text), first edition, 1525; _De Bello +adversus Turcam_, first edition, 1528; _De Peste_, first edition, 1554. + +The lost or partially completed works on subjects unrelated to mining, +of which some trace has been found, are:--_De Medicatis Fontibus_, _De +Putredine solidas partes_, etc., _Castigationes in Hippocratem_, +_Typographia Mysnae et Toringiae_, _De Traditionibus Apostolicis_, +_Oratio de rebus gestis Ernesti et Alberti_, _Ducum Saxoniae_. + + +REVIEW OF PRINCIPAL WORKS. + +Before proceeding with the bibliographical detail, we consider it +desirable to review briefly the most important of the author's works on +subjects related to mining. + +_De Natura Fossilium._ This is the most important work of Agricola, +excepting _De Re Metallica_. It has always been printed in combination +with other works, and first appeared at Basel, 1546. This edition was +considerably revised by the author, the amended edition being that of +1558, which we have used in giving references. The work comprises ten +"books" of a total of 217 folio pages. It is the first attempt at +systematic mineralogy, the minerals[1] being classified into (1) +"earths" (clay, ochre, etc.), (2) "stones properly so-called" (gems, +semi-precious and unusual stones, as distinguished from rocks), (3) +"solidified juices" (salt, vitriol, alum, etc.), (4) metals, and (5) +"compounds" (homogeneous "mixtures" of simple substances, thus forming +such minerals as galena, pyrite, etc.). In this classification Agricola +endeavoured to find some fundamental basis, and therefore adopted +solubility, fusibility, odour, taste, etc., but any true classification +without the atomic theory was, of course, impossible. However, he makes +a very creditable performance out of their properties and obvious +characteristics. All of the external characteristics which we use to-day +in discrimination, such as colour, hardness, lustre, etc., are +enumerated, the origin of these being attributed to the proportions of +the Peripatetic elements and their binary properties. Dana, in his great +work[2], among some fourscore minerals which he identifies as having +been described by Agricola and his predecessors, accredits a score to +Agricola himself. It is our belief, however, that although in a few +cases Agricola has been wrongly credited, there are still more of which +priority in description might be assigned to him. While a greater number +than fourscore of so-called species are given by Agricola and his +predecessors, many of these are, in our modern system, but varieties; +for instance, some eight or ten of the ancient species consist of one +form or another of silica. + +Book I. is devoted to mineral characteristics--colour, brilliance, +taste, shape, hardness, etc., and to the classification of minerals; +Book II., "earths"--clay, Lemnian earth, chalk, ochre, etc.; Book III., +"solidified juices"--salt, _nitrum_ (soda and potash), saltpetre, alum, +vitriol, chrysocolla, _caeruleum_ (part azurite), orpiment, realgar, and +sulphur; Book IV., camphor, bitumen, coal, bituminous shales, amber; +Book V., lodestone, bloodstone, gypsum, talc, asbestos, mica, calamine, +various fossils, geodes, emery, touchstones, pumice, fluorspar, and +quartz; Book VI., gems and precious stones; Book VII., "rocks"--marble, +serpentine, onyx, alabaster, limestone, etc.; Book VIII., metals--gold, +silver, quicksilver, copper, lead, tin, antimony, bismuth, iron, and +alloys, such as electrum, brass, etc.; Book IX., various furnace +operations, such as making brass, gilding, tinning, and products such as +slags, furnace accretions, _pompholyx_ (zinc oxide), copper flowers, +litharge, hearth-lead, verdigris, white-lead, red-lead, etc.; Book X., +"compounds," embracing the description of a number of recognisable +silver, copper, lead, quicksilver, iron, tin, antimony, and zinc +minerals, many of which we set out more fully in Note 8, page 108. + +_De Ortu et Causis Subterraneorum._ This work also has always been +published in company with others. The first edition was printed at +Basel, 1546; the second at Basel, 1558, which, being the edition +revised and added to by the author, has been used by us for reference. +There are five "books," and in the main they contain Agricola's +philosophical views on geologic phenomena. The largest portion of the +actual text is occupied with refutations of the ancient philosophers, +the alchemists, and the astrologers; and these portions, while they +exhibit his ability in observation and in dialectics, make but dull +reading. Those sections of the book which contain his own views, +however, are of the utmost importance in the history of science, and we +reproduce extensively the material relating to ore deposits in the +footnotes on pages 43 to 52. Briefly, Book I. is devoted to discussion +of the origin and distribution of ground waters and juices. The latter +part of this book and a portion of Book II. are devoted to the origin of +subterranean heat, which he assumes is in the main due to burning +bitumen--a genus which with him embraced coal--and also, in a minor +degree, to friction of internal winds and to burning sulphur. The +remainder of Book II. is mainly devoted to the discussion of +subterranean "air", "vapour", and "exhalations", and he conceives that +volcanic eruptions and earthquakes are due to their agency, and in these +hypotheses he comes fairly close to the modern theory of eruptions from +explosions of steam. "Vapour arises when the internal heat of the earth +or some hidden fire burns earth which is moistened with vapour. When +heat or subterranean fire meets with a great force of vapour which cold +has contracted and encompassed in every direction, then the vapour, +finding no outlet, tries to break through whatever is nearest to it, in +order to give place to the insistent and urgent cold. Heat and cold +cannot abide together in one place, but expel and drive each other out +of it by turns". + +As he was, we believe, the first to recognise the fundamental agencies +of mountain sculpture, we consider it is of sufficient interest to +warrant a reproduction of his views on this subject: "Hills and +mountains are produced by two forces, one of which is the power of +water, and the other the strength of the wind. There are three forces +which loosen and demolish the mountains, for in this case, to the power +of the water and the strength of the wind we must add the fire in the +interior of the earth. Now we can plainly see that a great abundance of +water produces mountains, for the torrents first of all wash out the +soft earth, next carry away the harder earth, and then roll down the +rocks, and thus in a few years they excavate the plains or slopes to a +considerable depth; this may be noticed in mountainous regions even by +unskilled observers. By such excavation to a great depth through many +ages, there rises an immense eminence on each side. When an eminence has +thus arisen, the earth rolls down, loosened by constant rain and split +away by frost, and the rocks, unless they are exceedingly firm, since +their seams are similarly softened by the damp, roll down into the +excavations below. This continues until the steep eminence is changed +into a slope. Each side of the excavation is said to be a mountain, just +as the bottom is called a valley. Moreover, streams, and to a far +greater extent rivers, effect the same results by their rushing and +washing; for this reason they are frequently seen flowing either between +very high mountains which they have created, or close by the shore +which borders them.... Nor did the hollow places which now contain the +seas all formerly exist, nor yet the mountains which check and break +their advance, but in many parts there was a level plain, until the +force of winds let loose upon it a tumultuous sea and a scathing tide. +By a similar process the impact of water entirely overthrows and +flattens out hills and mountains. But these changes of local conditions, +numerous and important as they are, are not noticed by the common people +to be taking place at the very moment when they are happening, because, +through their antiquity, the time, place, and manner in which they began +is far prior to human memory. The wind produces hills and mountains in +two ways: either when set loose and free from bonds, it violently moves +and agitates the sand; or else when, after having been driven into the +hidden recesses of the earth by cold, as into a prison, it struggles +with a great effort to burst out. For hills and mountains are created in +hot countries, whether they are situated by the sea coasts or in +districts remote from the sea, by the force of winds; these no longer +held in check by the valleys, but set free, heap up the sand and dust, +which they gather from all sides, to one spot, and a mass arises and +grows together. If time and space allow, it grows together and hardens, +but if it be not allowed (and in truth this is more often the case), the +same force again scatters the sand far and wide.... Then, on the other +hand, an earthquake either rends and tears away part of a mountain, or +engulfs and devours the whole mountain in some fearful chasm. In this +way it is recorded the Cybotus was destroyed, and it is believed that +within the memory of man an island under the rule of Denmark +disappeared. Historians tell us that Taygetus suffered a loss in this +way, and that Therasia was swallowed up with the island of Thera. Thus +it is clear that water and the powerful winds produce mountains, and +also scatter and destroy them. Fire only consumes them, and does not +produce at all, for part of the mountains--usually the inner part--takes +fire." + +The major portion of Book III. is devoted to the origin of ore channels, +which we reproduce at some length on page 47. In the latter part of Book +III., and in Books IV. and V., he discusses the principal divisions of +the mineral kingdom given in _De Natura Fossilium_, and the origin of +their characteristics. It involves a large amount of what now appears +fruitless tilting at the Peripatetics and the alchemists; but +nevertheless, embracing, as Agricola did, the fundamental Aristotelian +elements, he must needs find in these same elements and their +subordinate binary combinations cause for every variation in external +character. + +_Bermannus._ This, Agricola's first work in relation to mining, was +apparently first published at Basel, 1530. The work is in the form of a +dialogue between "Bermannus," who is described as a miner, mineralogist, +and "a student of mathematics and poetry," and "Nicolaus Ancon" and +"Johannes Naevius," both scholars and physicians. Ancon is supposed to +be of philosophical turn of mind and a student of Moorish literature, +Naevius to be particularly learned in the writings of Dioscorides, +Pliny, Galen, etc. "Bermannus" was probably an adaptation by Agricola +of the name of his friend Lorenz Berman, a prominent miner. The book is +in the main devoted to a correlation of the minerals mentioned by the +Ancients with those found in the Saxon mines. This phase is interesting +as indicating the natural trend of Agricola's scholastic mind when he +first comes into contact with the sciences to which he devoted himself. +The book opens with a letter of commendation from Erasmus, of Rotterdam, +and with the usual dedication and preface by the author. The three +conversationalists are supposed to take walks among the mines and to +discuss, incidentally, matters which come to their attention; therefore +the book has no systematic or logical arrangement. There are occasional +statements bearing on the history, management, titles, and methods used +in the mines, and on mining lore generally. The mineralogical part, +while of importance from the point of view of giving the first +description of several minerals, is immensely improved upon in _De +Natura Fossilium_, published 15 years later. It is of interest to find +here the first appearance of the names of many minerals which we have +since adopted from the German into our own nomenclature. Of importance +is the first description of bismuth, although, as pointed out on page +433, the metal had been mentioned before. In the revised collection of +collateral works published in 1558, the author makes many important +changes and adds some new material, but some of the later editions were +made from the unrevised older texts. + +_Rerum Metallicarum Interpretatio._ This list of German equivalents for +Latin mineralogical terms was prepared by Agricola himself, and first +appears in the 1546 collection of _De Ortu et Causis_, _De Natura +Fossilium_, etc., being repeated in all subsequent publications of these +works. It consists of some 500 Latin mineralogical and metallurgical +terms, many of which are of Agricola's own coinage. It is of great help +in translation and of great value in the study of mineralogic +nomenclature. + +_De Mensuris et Ponderibus._ This work is devoted to a discussion of the +Greek and Roman weights and measures, with some correlation to those +used in Saxony. It is a careful work still much referred to by students +of these subjects. The first edition was published at Paris in 1533, and +in the 1550 edition at Basel appears, for the first time, _De Precio +Metallorum et Monetis_. + +_De Veteribus et Novis Metallis._ This short work comprises 31 folio +pages, and first appears in the 1546 collection of collateral works. It +consists mainly of historical and geographical references to the +occurrence of metals and mines, culled from the Greek and Latin +classics, together with some information as to the history of the mines +in Central Europe. The latter is the only original material, and +unfortunately is not very extensive. We have incorporated some of this +information in the footnotes. + +_De Animantibus Subterraneis._ This short work was first printed in +Basel, 1549, and consists of one chapter of 23 folio pages. Practically +the whole is devoted to the discussion of various animals who at least a +portion of their time live underground, such as hibernating, +cave-dwelling, and burrowing animals, together with cave-dwelling birds, +lizards, crocodiles, serpents, etc. There are only a few lines of remote +geological interest as to migration of animals imposed by geologic +phenomena, such as earthquakes, floods, etc. This book also discloses an +occasional vein of credulity not to be expected from the author's other +works, in that he apparently believes Aristotle's story of the flies +which were born and lived only in the smelting furnace; and further, the +last paragraph in the book is devoted to underground gnomes. This we +reproduce in the footnote on page 217. + +_De Natura eorum quae Effluunt ex Terra._ This work of four books, +comprising 83 folio pages, first appears in the 1546 collection. As the +title indicates, the discussion is upon the substances which flow from +the earth, such as water, bitumen, gases, etc. Altogether it is of +microscopic value and wholly uninteresting. The major part refers to +colour, taste, temperature, medicinal uses of water, descriptions of +rivers, lakes, swamps, and aqueducts. + + +BIBLIOGRAPHICAL NOTES. + +For the following we have mainly to thank Miss Kathleen Schlesinger, who +has been employed many months in following up every clue, and although +the results display very considerable literary activity on the part of +the author, they do not by any means indicate Miss Schlesinger's +labours. Agricola's works were many of them published at various times +in combination, and therefore to set out the title and the publication +of each work separately would involve much repetition of titles, and we +consequently give the titles of the various volumes arranged according +to dates. For instance, _De Natura Fossilium_, _De Ortu et Causis_, _De +Veteribus et Novis Metallis_, _De Natura eorum quae Effluunt ex Terra_, +and _Interpretatio_ have always been published together, and the Latin +and Italian editions of these works always include _Bermannus_ as well. +Moreover, the Latin _De Re Metallica_ of 1657 includes all of these +works. + +We mark with an asterisk the titles to editions which we have been able +to authenticate by various means from actual books. Those unmarked are +editions which we are satisfied do exist, but the titles of which are +possibly incomplete, as they are taken from library catalogues, etc. +Other editions to which we find reference and of which we are not +certain are noted separately in the discussion later on.[3] + +*1530 (8vo): + + _Georgii Agricolae Medici, Bermannus sive de re Metallica._ + + (Froben's mark). + + _Basileae in aedibus Frobenianis Anno. MDXXX._ + + Bound with this edition is (p. 131-135), at least occasionally, + _Rerum metallicarum appellationes juxta vernaculam Germanorum + linguam, autori Plateano_. + + _Basileae in officina Frobeniana_, Anno. MDXXX. + +*1533 (8vo): + + _Georgii Agricolae Medici libri quinque de Mensuris et + Ponderibus: in quibus plaeraque à Budaeo et Portio parum + animadversa diligenter excutiuntur. Opus nunc primum in lucem + aeditum._ + + (Wechelus's Mark). + + _Parisiis. Excudebat Christianus Wechelus, in vico Iacobaeo, + sub scuto Basileiensi, Anno MDXXXIII._ + + 261 pages and index of 5 pages. + +*1533 (4to): + + _Georgii Agricolae Medici Libri quinque. De Mensuris et + Ponderibus: In quibus pleraque à Budaeo et Portio parum + animadversa diligenter excutiuntur._ + + (Froben's Mark). + + _Basileae ex Officina Frobeniana Anno MDXXXIII. Cum gratia et + privilegio Caesareo ad sex annos._ + + +1534 (4to): + + _Georgii Agricolae. Epistola ad Plateanum, cui sunt adiecta + aliquot loca castigata in libris de mensuris et ponderibus + nuper editis._ + + Froben, Basel, 1534. + +*1535 (8vo): + + _Georgii Agricolae Medici libri V. de Mensuris et Ponderibus: + in quibus pleraque à Budaeo et Portio parum animadversa + diligenter excutiuntur._ + + (Printer's Mark). + + At the end of Index: _Venitüs per Juan Anto. de Nicolinis de + Sabio, sumptu vero et requisitione Dñi Melchionis Sessae. Anno. + Dñi MDXXXV. Mense Julii._ 116 folios. + + On back of title page is given: _Liber primus de mensuris + Romanis, Secundus de mensuris Graecis, Tertius de rerum quas + metimur pondere, Quartus de ponderibus Romanis, Quintus de + ponderibus Graecis._ + +*1541 (8vo): + + _Georgii Agricolae Medici Bermannus sive de re metallica._ + + _Parisiis. Apud Hieronymum Gormontiú. In Vico Jacobeo sub + signotrium coronarum._ 1541. + +*1546 (8vo): + + _Georgii Agricolae medici Bermannus, sive de metallica ab + accurata autoris recognitione et emendatione nunc primum editus + cum nomenclatura rerum metallicarum. Eorum Lipsiae In officina + Valentini Papae Anno. MDXLVI._ + +*1546 (folio): + + _Georgii Agricolae De ortu et causis subterraneorum Lib. V. De + natura eorum quae effluunt ex terra Lib. IIII. De natura + fossilium Lib. X. De veteribus et novis metallis, Lib. II. + Bermannus sive De re Metallica dialogus. Interpretatio + Germanica vocum rei metallicae addito Indice faecundissimo._ + + _Apud Hieron Frobenium et Nicolaum Episcopium Basileae, MDXLVI. + Cum privilegio Imp. Maiestatis ad quinquennium._ + +*1549 (8vo): + + _Georgii Agricolae de animantibus subterraneis Liber._ + + Froben, Basel, MDXLIX. + +*1550 (8vo): + + _Di Georgio Agricola De la generatione de le cose, che sotto la + terra sono, e de le cause de' loro effetti e natura, Lib. V. De + La Natura di quelle cose, che de la terra scorrono Lib. IIII. + De La Natura de le cose Fossili, e che sotto la terra si Cavano + Lib. X. De Le Minere antiche e moderne Lib. II. Il Bermanno, ò + de le cose Metallice Dialogo, Recato tutto hora dal Latino in + Buona Lingua volgare._ + + (Vignette of Sybilla surrounded by the words)--_Qv Al Piv Fermo + E Il Mio Foglio È Il Mio Presaggio._ + + _Col Privilegio del Sommo Pontefice Papa Giulio III. Et del + Illustriss. Senato Veneto per anni. XX._ + + (Colophon). _In Vinegia per Michele Tramezzino, MDL._ + +*1550 (folio): + + _Georgii Agricolae. De Mensuris et ponderibus Rom. atque Graec. + lib. V. De externis mensuris et ponderibus Lib. II. Ad ea quae + Andreas Alciatus denuo disputavit De Mensuris et Ponderibus + brevis defensio Lib. I. De Mensuris quibus intervalla metimur + Lib. I. De restituendis ponderibus atque mensuris. Lib. I. De + precio metallorum et monetis. Lib. III._ + + _Basileae._ Froben. MDL. _Cum privilegio Imp. Maiestatis ad + quinquennium._[4] + +*1556 (folio): + + _Georgii Agricolae De Re Metallica Libri XII. quibus Officia, + Instrumenta, Machinae, ac omnia denique ad Metallicam + spectantia, non modo luculentissime describuntur, sed et per + effigies, suis locis insertas, adjunctis Latinis, Germanicisque + appellationibus ita ob oculos ponuntur, ut clarius tradi non + possint Eiusdem De Animantibus Subterraneis Liber, ab Autore + recognitus: cum Indicibus diversis, quicquid in opere tractatum + est, pulchre demonstrantibus._ + + (Froben's Mark). + + _Basileae MDLVI. Cum Privilegio Imperatoris in annos V. et + Galliarum Regis ad Sexennium._ + + Folio 538 pages and preface, glossary and index amounting to 86 + pages. This is the first edition of _De Re Metallica_. We + reproduce this title-page on page XIX. + +*1557 (folio): + + _Vom Bergkwerck xii Bücher darinn alle Empter, Instrument, + Gezeuge, unnd Alles zu disem Handel gehörig, mitt schönen + figuren vorbildet, und Klärlich beschriben seindt erstlich in + Lateinischer Sprach durch den Hochgelerten und weittberümpten + Herrn Georgium Agricolam, Doctorn und. Bürgermeistern der + Churfürstlichen statt Kempnitz, jezundt aber verteüscht durch + den Achtparen. unnd Hochgelerten Herrn Philippum Bechium, + Philosophen, Artzer und in der Loblichen Universitet zu Basel + Professorn._ + + _Gedruckt zu Basel durch Jeronymus Froben Und Niclausen + Bischoff im 1557 Jar mitt Keiserlicher Freyheit._ + +*1558 (folio): + + _Georgii Agricolae De ortu et causis subterraneorum Lib. V. De + natura eorum quae effluunt ex terra Lib. IV. De natura + fossilium Lib. X. De veteribus et novis metallis Lib. II. + Bermannus, sive De Re Metallica Dialogus Liber. Interpretatio + Germanica vocum rei metallicae, addito duplici Indice, altero + rerum, altero locorum Omnia ab ipso authore, cum haud + poenitenda accessione, recens recognita._ + + _Froben, et Episcop. Basileae MDLVIII. Cum Imp. Maiestatis + renovato privilegio ad quinquennium._ + + 270 pages and index. As the title states, this is a revised + edition by the author, and as the changes are very considerable + it should be the one used. The Italian translation and the 1612 + Wittenberg edition, mentioned below, are taken from the 1546 + edition, and are, therefore, very imperfect. + +*1561 (folio): + + Second edition of _De Re Metallica_ including _De Animantibus + Subterraneis_, with same title as the first edition except the + addition, after the body of the title, of the words _Atque + omnibus nunc iterum ad archetypum diligenter restitutis et + castigatis_ and the year MDLXI. 502 pages and 72 pages of + glossary and index. + +*1563 (folio): + + _Opera di Giorgio Agricola de L'arte de Metalli Partita in XII. + libri, ne quali si descrivano tutte le sorti, e qualità de gli + uffizii, de gli strumenti, delle macchine, e di tutte l'altre + cose attenenti a cotal arte, non pure con parole chiare ma + eziandio si mettano a luoghi loro le figure di dette cose, + ritratte al naturale, con l'aggiunta de nomi di quelle, cotanto + chiari, e spediti, che meglio non si puo desiderare, o havere._ + + _Aggiugnesi il libro del medesimo autore, che tratta de gl' + Animali di sottoterra da lui stesso corretto et riveduto. + Tradotti in lingua Toscana da M. Michelangelo Florio + Fiorentino._ + + _Con l'Indice di tutte le cose piu notabili alla fine_ + (Froben's mark) _in Basilea per Hieronimo Frobenio et Nicolao + Episcopio, MDLXIII._ + + 542 pages with 6 pages of index. + +*1580 (folio): + + _Bergwerck Buch: Darinn nicht Allain alle Empte Instrument + Gezeug und alles so zu diesem Handel gehörig mit figuren + vorgebildet und klärlich beschriben, etc. Durch den + Hochgelehrten ... Herrn Georgium Agricolam der Artzney Doctorn + und Burgermeister der Churfürstlichen Statt Kemnitz erstlich + mit grossem fleyss mühe und arbeit in Latein beschriben und in + zwölff Bücher abgetheilt: Nachmals aber durch den Achtbarn und + auch Hochgelehrten Philippum Bechium Philosophen Artzt und in + der Löblichen Universitet zu Basel Professorn mit sonderm + fleyss Teutscher Nation zu gut verteutscht und an Tag geben. + Allen Berckherrn Gewercken Berckmeistern Geschwornen + Schichtmeistern Steigern Berckheuwern Wäschern und Schmeltzern + nicht allein nützlich und dienstlich sondern auch zu wissem + hochnotwendig._ + + _Mit Römischer Keys. May Freyheit nicht nachzutrucken._ + + _Getruckt in der Keyserlichen Reichsstatt, Franckfort am Mayn, + etc. Im Jahr MDLXXX._ + +*1612 (12mo): + + _Georgii Agricolae De ortu et causis subterraneorum Lib. V. De + natura eorum quae effluunt ex terra, Lib. IV. De natura + fossilium Lib. X. De veteribus et novis metallis Lib. II. + Bermannus, sive de re metallica Dialogus. Interpretatio + Germanica vocum rei metallicae._ + + _Addito Indice faecundissimo, Plurimos jam annos à Germanis, et + externarum quoque nationum doctissimis viris, valde desiderati + et expetiti._ + + _Nunc vero in rei metallicae studiosorum gratiam recensiti, in + certa capita distributi, capitum argumentis, et nonnullis + scholiis marginalibus illustrati à Johanne Sigfrido Philos: et + Medicinae Doctore et in illustri Julia Professore ordinario._ + + _Accesserunt De metallicis rebus et nominibus observationes + variae et eruditae, ex schedis Georgii Fabricii, quibus ea + potissimum explicantur, quae Georgius Agricola praeteriit_. + + _Wittebergae Sumptibus Zachariae Schüreri Bibliopolae Typis + Andreae Rüdingeri, 1612._ + + There are 970 pages in the work of Agricola proper, the notes + of Fabricius comprising a further 44 pages, and the index 112 + pages. + +*1614 (8vo): + + _Georgii Agricolae De Animantibus Subterraneis Liber Hactenus à + multis desideratus, nunc vero in gratiam studiosorum seorsim + editus, in certa capita divisus, capitum argumentis et + nonnullis marginalibus exornatus à Johanne Sigfrido, Phil. & + Med. Doctore_, etc. + + _Wittebergae. Typis Meisnerianis: Impensis Zachariae. Schureri + Bibliop. Anno. MDCXIV._ + +*1621 (folio): + + _Georgii Agricolae Kempnicensis Medici ac Philosophi Clariss. + De Re Metallica Libri XII Quibus Officia, Instrumenta, + Machinae, ac omnia denique ad metallicam spectantia, non modo + Luculentissimè describuntur; sed et per effigies, suis locis + insertas adjunctis Latinis, Germanicisque; appellationibus, ita + ob oculos ponuntur, ut clarius tradi non possint._ + + _Ejusdem De Animantibus Subterraneis Liber, ab Autore + recognitus cum Indicibus diversis quicquid in Opere tractatum + est, pulchrè demonstrantibus._ + + (Vignette of man at assay furnace). + + _Basileae Helvet. Sumptibus itemque typis chalcographicis + Ludovici Regis Anno MDCXXI._ + + 502 pages and 58 pages glossary and indices. + +*1621 (folio): + + _Bergwerck Buch Darinnen nicht allein alle Empter Instrument + Gezeug und alles so zu disem Handel gehörig mit Figuren + vorgebildet und klärlich beschrieben:.... Durch den + Hochgelehrten und weitberühmten Herrn Georgium Agricolam, der + Artzney Doctorn und Burgermeister der Churfürstlichen Statt + Kemnitz Erstlich mit grossem fleiss mühe und arbeit in Latein + beschrieben und in zwölff Bücher abgetheilt: Nachmals aber + durch den Achtbarn und auch Hochgelehrten Philippum Bechium. + Philosophen, Artzt, und in der loblichen Universitet zu Basel + Professorn mit sonderm fleiss Teutscher Nation zu gut + verteutscht und an Tag geben und nun zum andern mal getruckt._ + + _Allen Bergherrn Gewercken Bergmeistern Geschwornen + Schichtmeistern Steigern Berghäwern Wäschern unnd Schmeltzern + nicht allein nutzlich und dienstlich sondern auch zu wissen + hochnohtwendig._ + + (Vignette of man at assay furnace). + + _Getruckt zu Basel inverlegung Ludwig Königs Im Jahr, MDCXXI._ + + 491 pages 5 pages glossary--no index. + +*1657 (folio): + + _Georgii Agricolae Kempnicensis Medici ac Philosophi Clariss. + De Re Metallica Libri XII. Quibus Officia, instrumenta, + machinae, ac omnia denique ad metallicam spectantia, non modo + luculentissimè describuntur: sed et per effigies, suis locis + insertas, adjunctis Latinis, Germanicisque appellationibus, ita + ob oculos ponuntur, ut clarius tradi non possint. Quibus + accesserunt hac ultima editione, Tractatus ejusdem argumenti, + ab eodem conscripti, sequentes._ + + _De Animantibus Subterraneis Lib. I., De Ortu et Causis + Subterraneorum Lib. V., De Natura eorum quae effluunt ex Terra + Lib. IV., De Natura Fossilium Lib. X., De Veteribus et Novis + Metallis Lib. II., Bermannus sive de Re Metallica, Dialogus + Lib. I._ + + _Cum Indicibus diversis, quicquid in Opere tractatum est, + pulchrè demonstrantibus._ + + (Vignette of assayer and furnace). + + _Basileae Sumptibus et Typis Emanuelis König. Anno MDCLVII._ + + Folio, 708 pages and 90 pages of glossary and indices. This is + a very serviceable edition of all of Agricola's important + works, and so far as we have noticed there are but few + typographical errors. + +*1778 (8vo): + + _Gespräch vom Bergwesen, wegen seiner Fürtrefflich keit aus dem + Lateinischen in das Deutsche übersetzet, mit nützl. Anmerkungen + erläutert. u. mit einem ganz neuen Zusatze von Zlüglicher + Anstellung des Bergbaues u. von der Zugutemachung der Erze auf + den Hüttenwerken versehen von Johann Gottlieb Stör._ + + _Rotenburg a. d. Fulda, Hermstädt 1778._ 180 pages. + +*1806 (8vo): + + _Georg Agricola's Bermannus eine Einleitung in die + metallurgischen Schriften desselben, übersetzt und mit + Exkursionen herausgegeben von Friedrich August Schmid. + Haushalts- und Befahrungs-Protokollist im Churf. vereinigten + Bergamte zu St. Annaberg._ + + _Freyberg 1806. Bey Craz und Gerlach._ + +*1807-12 (8vo). + + _Georg Agrikola's Mineralogische Schriften übersetzt und mit + erläuternden Anmerkungen. Begleitet von Ernst Lehmann + Bergamts-Assessor, Berg- Gegen- und Receszschreiber in Dem + Königl. Sächs. Bergamte Voigtsberg der jenaischen Societät für + die gesammte Mineralogie Ehrenmitgliede._ + + _Freyberg, 1807-12. Bey Craz und Gerlach._ + + This German translation consists of four parts: the first being + _De Ortu et Causis_, the second _De Natura eorum quae effluunt + ex terra_, and the third in two volumes _De Natura Fossilium_, + the fourth _De Veteribus et Novis Metallis_; with glossary and + index to the four parts. + +We give the following notes on other possible prints, as a great many +references to the above works occur in various quarters, of date other +than the above. Unless otherwise convinced it is our belief that most of +these refer to the prints given above, and are due to error in giving +titles or dates. It is always possible that such prints do exist and +have escaped our search. + +_De Re Metallica._ Leupold, Richter, Schmid, van der Linden, Mercklinus +and Eloy give an 8vo edition of _De Re Metallica_ without illustrations, +Schweinfurt, 1607. We have found no trace of this print. Leupold, van +der Linden, Richter, Schmid and Eloy mention an 8vo edition, Wittenberg, +1614. It is our belief that this refers to the 1612 Wittenberg edition +of the selected works, which contains a somewhat similar title referring +in reality to _Bermannus_, which was and is still continually confused +with _De Re Metallica_. Ferguson mentions a German edition, Schweinfurt, +8vo, 1687. We can find no trace of this; it may refer to the 1607 +Schweinfurt edition mentioned above. + +_De Natura Fossilium._ Leupold and Gatter refer to a folio edition of +1550. This was probably an error for either the 1546 or the 1558 +editions. Watt refers to an edition of 1561 combined with _De Medicatis +Fontibus_. We find no trace of such edition, nor even that the latter +work was ever actually printed. He also refers to an edition of 1614 and +one of 1621, this probably being an error for the 1612 edition of the +subsidiary works and the _De Re Metallica_ of 1621. Leupold also refers +to an edition of 1622, this probably being an error for 1612. + +_De Ortu et Causis._ Albinus, Hofmann, Jacobi, Schmid, Richter, and +Reuss mention an edition of 1544. This we believe to be an error in +giving the date of the dedication instead of that of the publication +(1546). Albinus and Ferguson give an edition of 1555, which date is, we +believe, an error for 1558. Ferguson gives an edition of the Italian +translation as 1559; we believe this should be 1550. Draud gives an +edition of 1621; probably this should be 1612. + +_Bermannus._ Albinus, Schmid, Reuss, Richter, and Weinart give the first +edition as 1528. We have been unable to learn of any actual copy of that +date, and it is our belief that the date is taken from the dedication +instead of from the publication, and should be 1530. Leupold, Schmid, +and Reuss give an edition by Froben in 1549; we have been unable to +confirm this. Leupold also gives an edition of 1550 (folio), and Jöcher +gives an edition of Geneva 1561 (folio); we have also been unable to +find this, and believe the latter to be a confusion with the _De Re +Metallica_ of 1561, as it is unlikely that _Bermannus_ would be +published by itself in folio. The catalogue of the library at Siena +(Vol. III., p. 78) gives _Il Bermanno, Vinegia_, 1550, 8vo. We have +found no trace of this edition elsewhere. + +_De Mensuris et Ponderibus._ Albinus and Schmid mention an edition of +1539, and one of 1550. The Biographie Universelle, Paris, gives one of +1553, and Leupold one of 1714, all of which we have been unable to find. +An epitome of this work was published at various times, sometimes in +connection with editions of Vitruvius; so far as we are aware on the +following dates, 1552, 1585, 1586, 1829. There also appear extracts in +relation to liquid measures in works entitled _Vocabula rei numariae +ponderum et mensurarum_, etc. Paul Eber and Caspar Peucer, _Lipsiae_, +1549, and in same Wittenberg, 1552. + +_De Veteribus et Novis Metallis._ Watt gives an edition, Basel, 1530, +and Paris, 1541; we believe this is incorrect and refers to _Bermannus_. +Reuss mentions a folio print of Basel, 1550. We consider this very +unlikely. + +_De Natura eorum quae Effluunt ex Terra._ Albinus, Hofmann, Schmid, +Jacobi, Richter, Reuss, and Weinart give an edition of 1545. We believe +this is again the dedication instead of the publication date (1546). + +_De Animantibus Subterraneis._ Van der Linden gives an edition at +Schweinfurt, 8vo, 1607. Although we have been unable to find a copy, +this slightly confirms the possibility of an octavo edition of _De Re +Metallica_ of this date, as they were usually published together. +Leupold gives assurance that he handled an octavo edition of Wittenberg, +1612, _cum notis Johann Sigfridi_. We think he confused this with +_Bermannus sive de re metallica_ of that date and place. Schmid, +Richter, and Draud all refer to an edition similarly annotated, Leipzig, +1613, 8vo. We have no trace of it otherwise. + + +UNPUBLISHED WORKS ON SUBJECTS RELATED TO MINING. + +Agricola apparently projected a complete series of works covering the +whole range of subjects relating to minerals: geology, mineralogy, +mining, metallurgy, history of metals, their uses, laws, etc. In a +letter[5] from Fabricius to Meurer (March, 1553), the former states that +Agricola intended writing about 30 books (chapters) in addition to those +already published, and to the twelve books _De Re Metallica_ which he +was about to publish. Apparently a number of these works were either +unfinished or unpublished at Agricola's death, for his friend George +Fabricius seems to have made some effort to secure their publication, +but did not succeed, through lack of sympathy on the part of Agricola's +family. Hofmann[6] states on this matter: "His intentions were +frustrated mainly through the lack of support with which he was met by +the heirs of the Mineralogist. These, as he complains to a Councillor of +the Electorate, Christopher von Carlovitz, in 1556, and to Paul Eber in +another letter, adopted a grudging and ungracious tone with regard to +his proposal to collect all Agricola's works left behind, and they only +consented to communicate to him as much as they were obliged by express +command of the Prince. At the Prince's command they showed him a little, +but he supposed that there was much more that they had suppressed or not +preserved. The attempt to purchase some of the works--the Elector had +given Fabricius money for the purpose (30 nummos unciales)--proved +unavailing, owing to the disagreeableness of Agricola's heirs. It is no +doubt due to these regrettable circumstances that all the works of the +industrious scholar did not come down to us." The "disagreeableness" was +probably due to the refusal of the Protestant townsfolk to allow the +burial of Agricola in the Cathedral at Chemnitz. So far as we know the +following are the unpublished or lost works. + +_De Jure et Legibus Metallicis._ This work on mining law is mentioned at +the end of Book IV. of _De Re Metallica_, and it is referred to by +others apparently from that source. We have been unable to find any +evidence that it was ever published. + +_De Varia temperie sive Constitutione Aeris._ In a letter[7] to Johann +Naevius, Agricola refers to having a work in hand of this title. + +_De Metallis et Machinis._ Hofmann[8] states that a work of this title +by Agricola, dated Basel 1543, was sold to someone in America by a +Frankfort-on-Main bookseller in 1896. This is apparently the only +reference to it that we know of, and it is possibly a confusion of +titles or a "separate" of some chapters from _De Re Metallica_. + +_De Ortu Metallorum Defensio ad Jacobum Scheckium._ Referred to by +Fabricius in a letter[9] to Meurer. If published was probably only a +tract. + +_De Terrae Motu._ In a letter[10] from Agricola to Meurer (Jan. 1, 1544) +is some reference which might indicate that he was formulating a work on +earthquakes under this title, or perhaps may be only incidental to the +portions of _De Ortu et Causis_ dealing with this subject. + +_Commentariorum in quibus utriusque linguae scriptorum locos difficiles +de rebus subterraneis explicat, Libri VI._ Agricola apparently partially +completed a work under some such title as this, which was to embrace +chapters entitled _De Methodis_ and _De Demonstratione_. The main object +seems to have been a commentary on the terms and passages in the +classics relating to mining, mineralogy, etc. It is mentioned in the +Preface of _De Veteribus et Novis Metallis_, and in a letter[11] from +one of Froben's firm to Agricola in 1548, where it is suggested that +Agricola should defer sending his new commentaries until the following +spring. The work is mentioned by Albinus[12], and in a letter from Georg +Fabricius to Meurer on the 2nd Jan. 1548,[13] in another from G. +Fabricius, to his brother Andreas on Oct. 28, 1555,[14] and in a third +from Fabricius to Melanchthon on December 8th, 1555[15], in which regret +is expressed that the work was not completed by Agricola. + + +WRITINGS NOT RELATED TO MINING, INCLUDING LOST OR UNPUBLISHED WORKS. + +_Latin Grammar._ This was probably the first of Agricola's publications, +the full title to which is _Georgii Agricolae Glaucii Libellus de prima +ac simplici institutione grammatica. Excusum Lipsiae in Officina +Melchioris Lottheri. Anno MDXX._ (4to), 24 folios.[16] There is some +reason to believe that Agricola also published a Greek grammar, for +there is a letter[17] from Agricola dated March 18th, 1522, in which +Henicus Camitianus is requested to send a copy to Stephan Roth. + +_Theological Tracts._ There are preserved in the Zwickau Rathsschul +Library[18] copies by Stephan Roth of two tracts, the one entitled, +_Deum non esse auctorem Peccati_, the other, _Religioso patri Petri +Fontano, sacre theologie Doctori eximio Georgius Agricola salutem dicit +in Christo_. The former was written from Leipzig in 1522, and the +latter, although not dated, is assigned to the same period. Both are +printed in _Zwei theologische Abhandlungen des Georg Agricola_, an +article by Otto Clemen, _Neuen Archiv fur Sächsische Geschichte_, etc., +Dresden, 1900. There is some reason (from a letter of Fabricius to +Melanchthon, Dec. 8th, 1555) to believe that Agricola had completed a +work on the unwritten traditions concerning the Church. There is no +further trace of it. + +_Galen._ Agricola appears to have been joint author with Andreas +Asulanus and J. B. Opizo of a revision of this well-known Greek work. It +was published at Venice in 1525, under the title of _Galeni Librorum_, +etc., etc. Agricola's name is mentioned in a prefatory letter to Opizo +by Asulanus. + +_De Bello adversus Turcam._ This political tract, directed against the +Turks, was written in Latin and first printed by Froben, Basel, 1528. It +was translated into German apparently by Agricola's friend Laurenz +Berman, and published under the title _Oration Anrede Und Vormanunge ... +widder den Türcken_ by Frederich Peypus, Nuremberg, in 1531 (8vo), and +either in 1530 or 1531 by Wolfgang Stöckel, Dresden, 4to. It was again +printed in Latin by Froben, Basel, 1538, 4to; by H. Grosius, Leipzig, +1594, 8vo; it was included among other works published on the same +subject by Nicholas Reusnerus, Leipzig, 1595; by Michael Lantzenberger, +Frankfurt-am-Main, 1597, 4to. Further, there is reference by Watt to an +edition at Eisleben, 1603, of which we have no confirmation. There is +another work on the subject, or a revision by the author mentioned by +Albinus[19] as having been, after Agricola's death, sent to Froben by +George Fabricius to be printed; nothing further appears in this matter +however. + +_De Peste._ This work on the Plague appears to have been first printed +by Froben, Basel, 1554, 8vo. The work was republished at Schweinfurt, +1607, and at Augsburg in 1614, under various editors. It would appear +from Albinus[20] that the work was revised by Agricola and in Froben's +hands for publication after the author's death. + +_De Medicatis Fontibus._ This work is referred to by Agricola himself in +_De Natura Eorum_,[21] in the prefatory letter in _De Veteribus et Novis +Metallis_; and Albinus[22] quotes a letter of Agricola to Sebastian +Munster on the subject. Albinus states (_Bergchronik_, p. 193) that to +his knowledge it had not yet been published. Conrad Gesner, in his work +_Excerptorum et observationum de Thermis_, which is reprinted in _De +Balneis_, Venice, 1553, after Agricola's _De Natura Eorum_, states[23] +concerning Agricola _in libris quos de medicatis fontibus instituerit +copiosus se dicturum pollicetur_. Watt mentions it as having been +published in 1549, 1561, 1614, and 1621. He, however, apparently +confuses it with _De Natura Eorum_. We are unable to state whether it +was ever printed or not. A note of inquiry to the principal libraries in +Germany gave a negative result. + +_De Putredine solidas partes humani corporis corrumpente._ This work, +according to Albinus was received by Fabricius a year after Agricola's +death, but whether it was published or not is uncertain.[24] + +_Castigationes in Hippocratem et Galenum._ This work is referred to by +Agricola in the preface of _Bermannus_, and Albinus[25] mentions several +letters referring to the preparation of the work. There is no evidence +of publication. + +_Typographia Mysnae et Toringiae._ It seems from Agricola's letter[26] +to Munster that Agricola prepared some sort of a work on the history of +Saxony and of the Royal Family thereof at the command of the Elector +and sent it to him when finished, but it was never published as written +by Agricola. Albinus, Hofmann, and Struve give some details of letters +in reference to it. Fabricius in a letter[27] dated Nov. 11, 1536 asks +Meurer to send Agricola some material for it; in a letter from Fabricius +to Meurer dated Oct. 30, 1554, it appears that the Elector had granted +Agricola 200 thalers to assist in the work. After Agricola's death the +material seems to have been handed over to Fabricius, who made use of it +(as he states in the preface) in preparing the work he was commissioned +by the Elector to write, the title of which was, _Originum +illustrissimae stirpis Saxonicae Libri_, and was published in Leipzig, +1597. It includes on page 880 a fragment of a work entitled _Oratio de +rebus Gestis Ernesti et Alberti Ducum Saxoniae_, by Agricola. + + +WORKS WRONGLY ATTRIBUTED TO GEORGIUS AGRICOLA. + +The following works have been at one time or another wrongly attributed +to Georgius Agricola:-- + +_Galerazeya sive Revelator Secretorum De Lapide Philosophorum_, Cologne, +1531 and 1534, by one Daniel Agricola, which is merely a controversial +book with a catch-title, used by Catholics for converting heretics. + +_Rechter Gebrauch der Alchimey_, a book of miscellaneous receipts which +treats very slightly of transmutation.[28] + +_Chronik der Stadt Freiberg_ by a Georg Agricola (died 1630), a preacher +at Freiberg. + +_Dominatores Saxonici_, by the same author. + +_Breviarum de Asse_ by Guillaume Bude. + +_De Inventione Dialectica_ by Rudolph Agricola. + + +FOOTNOTES: + +[1] See footnote 4, page 1. + +[2] System of Mineralogy. + +[3] The following are the titles of the works referred to in this +discussion:-- + +Petrus Albinus: _Meissnische Land und Berg Chronica In welcher ein +wollnstendige description des Landes_, etc., Dresden, 1590 (contains +part I, _Commentatorium de Mysnia_). _Newe Chronica und Beschreibung des +Landes zu Meissen_, pp. 1 to 449, besides preface and index, and Part +II. _Meissnische Bergk Chronica_, Dresden, 1590, pp. 1 to 205, besides +preface and index. + +Adam Daniel Richter: _Umständliche ... Chronica der ... Stadt Chemnitz +nebst beygefügten Urkunden_, 2 pts. 4to, Zittau & Leipzig, 1767. + +Ben. G. Weinart: _Versuch einer Litteratur d. Sächsischen Geschichte und +Staats kunde_, Leipzig, 1885. + +Friedrich August Schmid: _Georg Agrikola's Bermannus: Einleitung in die +metallurgischen Schriften desselben_, Freyberg, Craz & Gerlach. 1806, +pp. VIII., 1-260. + +Franz Ambros Reuss: _Mineralogische Geographie van Böhmen_. 2 vols. 4to, +Dresden, 1793-97. (Agricola Vol. I, p. 2). + +Jacob Leupold: _Prodromus Bibliothecae Metallicae_, corrected, +continued, and augmented by F. E. Brückmann. Wolfenbüttel, 1732, s.v. +Agricola. + +Christian Gottlieb Göcher: _Allgemeines Gelehrten-Lexicon_, with +continuation and supplements by Adelung, Leipzig, 1750, s.v. Agricola. + +John Anton Van der Linden: _De Scriptis medicis, Libri duo_, Amsterdam, +1662, s.v. Georgius Agricola. + +Nicolas François Joseph Eloy: _Dictionnaire Historique de la Médecine_, +Liége & Francfort (chez J. F. Bassompierre), 1755, 8vo (Agricola p. 28, +vol. I). + +Georg Abraham Mercklinus: _Lindenius Renovatus de scriptis medicis +continuati ... amplificati_, etc., Amsterdam, 1686, s.v. Georgius +Agricola. + +John Ferguson: _Bibliotheca Chemica_: A catalogue of the Alchemical, +Chemical, and Pharmaceutical books in the collection of the late James +Young of Kelly & Durris, Esq., L.L.D., F.R.S., F.R.S.E. Glasgow, 1906, +4to, 2 vols., s.v. Agricola. + +Christoph Wilhelm Gatterer: _Allgemeines Repertorium der +mineralogischen, bergwerks und Salz werkswissenschaftlichen Literatur_, +Göttingen, 1798, vol. I. + +Dr. Reinhold Hofmann: _Dr. Georg Agricola, Ein Gelehrtenleben aus dem +Zeitalter der Reformation_, 8vo, Gotha, 1905. + +Georg Heinrich Jacobi: _Der Mineralog Georgius Agricola und sein +Verhältnis zur wissenschaft seiner Zeit_, etc., 8vo. Zwickau (1889), +(_Dissertation_--Leipzig). + +Georg Draud: _Bibliotheca Classica_, Frankfurt-am-Main, 1611. + +B. G. Struve: _Bibliotheca Saxonica_, 8vo, Halle, 1736. + +[4] Albinus states (p. 354): _Omnes simul editi Anno. 1549, iterum 1550, +Basileae_, as though two separate editions. + +[5] _G. Fabricii epistolae ad W. Meurerum et alios aequales_, by +Baumgarten-Crusius, Leipzig, 1845, p. 83. + +[6] _Dr. Georg Agricola_, Gotha, 1905, pp. 60-61. + +[7] Albinus, _Landchronik_, pp. 354-5. + +[8] _Dr. Georg Agricola_, p. 63. + +[9] _Baumgarten-Crusius_, p. 115. + +[10] _Virorum Clarorum Saec. XVI. et XVII._ _Epistolae Selectae_ by +Ernst Weber, Leipzig, 1894, p. 2. + +[11] Nicholas Episcopius to Georg Agricola, Sept. 17, 1548, published in +Schmid's _Bermannus_ p. 38. See also Hofmann, op. cit. pp. 62 and 140. + +[12] _Meissnische Landchronik_, Dresden, 1589, p. 354. + +[13] Printed in Baumgarten-Crusius, pp. 48-49, letter XLVIII. + +[14] Printed in Hermann Peter's _Meissner Jahresbericht der +Fürstenschule_, 1891, p. 24. + +[15] Baumgarten-Crusius. _Georgii Fabricii Chemnicensis Epistolae_, +Leipzig, 1845, p. 139. + +[16] There is a copy of this work in the Rathsschul Library at Zwickau. + +[17] In the Rathsschul Library at Zwickau. + +[18] Contained in Vols. XXXVII. and XL. of Stephan Roth's +_Kollectanenbände_ Volumes of Transcripts. + +[19] _Landchronik_, p. 354. + +[20] Op. cit., p. 354. + +[21] Book IV. + +[22] Op. cit., p. 355. + +[23] Page 291. + +[24] See Baumgarten-Crusius, p. 114, letter from Georg Fabricius. + +[25] Op. cit., p. 354. + +[26] Albinus, Op. cit., p. 355. + +[27] Baumgarten-Crusius, p. 2. + +[28] See Ferguson, _Bibliotheca Chemica_, s.v. Daniel Agricola. + + + + +APPENDIX B. + +ANCIENT AUTHORS. + + +We give the following brief notes on early works containing some +reference to mineralogy, mining, or metallurgy, to indicate the +literature available to Agricola and for historical notes bearing upon +the subject. References to these works in the footnotes may be most +easily consulted through the personal index. + +GREEK AUTHORS.--Only a very limited Greek literature upon subjects +allied to mining or natural science survives. The whole of the material +of technical interest could be reproduced on less than twenty of these +pages. Those of most importance are: Aristotle (384-322 B.C.), +Theophrastus (371-288 B.C.), Diodorus Siculus (1st Century B.C.), Strabo +(64 B.C.-25 A.D.), and Dioscorides (1st Century A.D.). + +Aristotle, apart from occasional mineralogical or metallurgical +references in _De Mirabilibus_, is mostly of interest as the author of +the Peripatetic theory of the elements and the relation of these to the +origin of stones and metals. Agricola was, to a considerable measure, a +follower of this school, and their views colour much of his writings. +We, however, discuss elsewhere[1] at what point he departed from them. +Especially in _De Ortu et Causis_ does he quote largely from Aristotle's +_Meteorologica_, _Physica_, and _De Coelo_ on these subjects. There is a +spurious work on stones attributed to Aristotle of some interest to +mineralogists. It was probably the work of some Arab early in the Middle +Ages. + +Theophrastus, the principal disciple of Aristotle, appears to have +written at least two works relating to our subject--one "On Stones", and +the other on metals, mining or metallurgy, but the latter is not extant. +The work "On Stones" was first printed in Venice in 1498, and the Greek +text, together with a fair English translation by Sir John Hill, was +published in London in 1746 under the title "Theophrastus on Stones"; +the translation is, however, somewhat coloured with Hill's views on +mineralogy. The work comprises 120 short paragraphs, and would, if +reproduced, cover but about four of these pages. In the first paragraphs +are the Peripatetic view of the origin of stones and minerals, and upon +the foundation of Aristotle he makes some modifications. The principal +interest in Theophrastus' work is the description of minerals; the +information given is, however, such as might be possessed by any +ordinary workman, and betrays no particular abilities for natural +philosophy. He enumerates various exterior characteristics, such as +colour, tenacity, hardness, smoothness, density, fusibility, lustre, and +transparence, and their quality of reproduction, and then proceeds to +describe various substances, but usually omits his enumerated +characteristics. Apart from the then known metals and certain "earths" +(ochre, marls, clay, etc.), it is possible to identify from his +descriptions the following rocks and minerals:--marble, pumice, onyx, +gypsum, pyrites, coal, bitumen, amber, azurite, chrysocolla, realgar, +orpiment, cinnabar, quartz in various forms, lapis lazuli, emerald, +sapphire, diamond, and ruby. Altogether there are some sixteen distinct +mineral species. He also describes the touchstone and its uses, the +making of white-lead and verdigris, and of quicksilver from cinnabar. + +Diodorus Siculus was a Greek native of Sicily. His "historical library" +consisted of some 40 books, of which parts of 15 are extant. The first +print was in Latin, 1472, and in Greek in 1539; the first translation +into English was by Thomas Stocker, London, 1568, and later by G. Booth, +1700. We have relied upon Booth's translation, but with some amendments +by friends, to gain more literal statement. Diodorus, so far as relates +to our subject, gives merely the occasional note of a traveller. The +most interesting paragraphs are his quotation from Agatharchides on +Egyptian mining and upon British tin. + +Strabo was also a geographer. His work consists of 17 books, and +practically all survive. We have relied upon the most excellent +translation of Hamilton and Falconer, London, 1903, the only one in +English. Mines and minerals did not escape such an acute geographer, and +the matters of greatest interest are those with relation to Spanish +mines. + +Dioscorides was a Greek physician who wrote entirely from the standpoint +of materia medica, most of his work being devoted to herbs; but Book V. +is devoted to minerals and rocks, and their preparation for medicinal +purposes. The work has never been translated into English, and we have +relied upon the Latin translation of Matthioli, Venice, 1565, and notes +upon the Greek text prepared for us by Mr. C. Katopodes. In addition to +most of the substances known before, he, so far as can be identified, +adds schist, _cadmia_ (blende or calamine), _chalcitis_ (copper +sulphide), _misy_, _melanteria_, _sory_ (copper or iron sulphide +oxidation minerals). He describes the making of certain artificial +products, such as copper oxides, vitriol, litharge, _pompholyx_, and +_spodos_ (zinc and/or arsenical oxides). His principal interest for us, +however, lies in the processes set out for making his medicines. + +Occasional scraps of information relating to the metals or mines in some +connection are to be found in many other Greek writers, and in +quotations by them from others which are not now extant, such as +Polybius, Posidonius, etc. The poets occasionally throw a gleam of +light on ancient metallurgy, as for instance in Homer's description of +Vulcan's foundry; while the historians, philosophers, statesmen, and +physicians, among them Herodotus, Xenophon, Demosthenes, Galen, and many +others, have left some incidental references to the metals and mining, +helpful to gleaners from a field, which has been almost exhausted by +time. Even Archimedes made pumps, and Hero surveying instruments for +mines. + +ROMAN AUTHORS.--Pre-eminent among all ancient writers on these subjects +is, of course, Pliny, and in fact, except some few lines by Vitruvius, +there is practically little else in extant Roman literature of technical +interest, for the metallurgical metaphors of the poets and orators were +threadbare by this time, and do not excite so much interest as upon +their first appearance among the Greeks and Hebrews. + +Pliny (Caius Plinius Secundus) was born 23 A.D., and was killed by +eruption of Vesuvius 79 A.D. His Natural History should be more properly +called an encyclopædia, the whole comprising 37 books; but only portions +of the last four books relate to our subject, and over one-half of the +material there is upon precious stones. To give some rough idea of the +small quantity of even this, the most voluminous of ancient works upon +our subject, we have made an estimate that the portions of metallurgical +character would cover, say, three pages of this text, on mining two +pages, on building and precious stones about ten pages. Pliny and +Dioscorides were contemporaries, and while Pliny nowhere refers to the +Greek, internal evidence is most convincing, either that they drew from +the same source, or that Pliny drew from Dioscorides. We have, +therefore, throughout the text given precedence in time to the Greek +author in matters of historical interest. The works of Pliny were first +printed at Venice in 1469. They have passed dozens of editions in +various languages, and have been twice translated into English. The +first translation by Philemon Holland, London, 1601, is quite +impossible. The second translation, by Bostock and Riley, London, 1855, +was a great advance, and the notes are most valuable, but in general the +work has suffered from a freedom justifiable in the translation of +poetry, but not in science. We have relied upon the Latin edition of +Janus, Leipzig, 1870. The frequent quotations in our footnotes are +sufficient indication of the character of Pliny's work. In general it +should be remembered that he was himself but a compiler of information +from others, and, so far as our subjects are concerned, of no other +experience than most travellers. When one considers the reliability of +such authors to-day on technical subjects, respect for Pliny is much +enhanced. Further, the text is no doubt much corrupted through the +generations of transcription before it was set in type. So far as can be +identified with any assurance, Pliny adds but few distinct minerals to +those enumerated by Theophrastus and Dioscorides. For his metallurgical +and mining information we refer to the footnotes, and in general it may +be said that while those skilled in metallurgy can dimly see in his +statements many metallurgical operations, there is little that does not +require much deduction to arrive at a conclusion. On geology he offers +no new philosophical deductions of consequence; the remote connection of +building stones is practically all that can be enumerated, lest one +build some assumption of a knowledge of ore-deposits on the use of the +word "vein". One point of great interest to this work is that in his +search for Latin terms for technical purposes Agricola relied almost +wholly upon Pliny, and by some devotion to the latter we have been able +to disentangle some very puzzling matters of nomenclature in _De Re +Metallica_, of which the term _molybdaena_ may be cited as a case in +point. + +Vitruvius was a Roman architect of note of the 1st Century B.C. His work +of ten books contains some very minor references to pumps and machinery, +building stones, and the preparation of pigments, the latter involving +operations from which metallurgical deductions can occasionally be +safely made. His works were apparently first printed in Rome in 1496. +There are many editions in various languages, the first English +translation being from the French in 1692. We have relied upon the +translation of Joseph Gwilt, London, 1875, with such alterations as we +have considered necessary. + +MEDIÆVAL AUTHORS.--For convenience we group under this heading the +writers of interest from Roman times to the awakening of learning in the +early 16th Century. Apart from Theophilus, they are mostly alchemists; +but, nevertheless, some are of great importance in the history of +metallurgy and chemistry. Omitting a horde of lesser lights upon whom we +have given some data under the author's preface, the works principally +concerned are those ascribed to Avicenna, Theophilus, Geber, Albertus +Magnus, Roger Bacon, and Basil Valentine. Judging from the Preface to +_De Re Metallica_, and from quotations in his subsidiary works, Agricola +must have been not only familiar with a wide range of alchemistic +material, but also with a good deal of the Arabic literature, which had +been translated into Latin. The Arabs were, of course, the only race +which kept the light of science burning during the Dark Ages, and their +works were in considerable vogue at Agricola's time. + +Avicenna (980-1037) was an Arabian physician of great note, a translator +of the Greek classics into Arabic, and a follower of Aristotle to the +extent of attempting to reconcile the Peripatetic elements with those of +the alchemists. He is chiefly known to the world through the works which +he compiled on medicine, mostly from the Greek and Latin authors. These +works for centuries dominated the medical world, and were used in +certain European Universities until the 17th century. A great many works +are attributed to him, and he is copiously quoted by Agricola, +principally in his _De Ortu et Causis_, apparently for the purpose of +exposure. + +Theophilus was a Monk and the author of a most illuminating work, +largely upon working metal and its decoration for ecclesiastical +purposes. An excellent translation, with the Latin text, was published +by Robert Hendrie, London, 1847, under the title "An Essay upon various +Arts, in three books, by Theophilus, called also Rugerus, Priest and +Monk." Hendrie, for many sufficient reasons, places the period of +Theophilus as the latter half of the 11th century. The work is mainly +devoted to preparing pigments, making glass, and working metals, and +their conversion into ecclesiastical paraphernalia, such as mural +decoration, pictures, windows, chalices, censers, bells, organs, etc. +However, he incidentally describes the making of metallurgical furnaces, +cupellation, parting gold and silver by cementation with salt, and by +melting with sulphur, the smelting of copper, liquating lead from it, +and the refining of copper under a blast with poling. + +Geber was until recent years considered to be an Arab alchemist of a +period somewhere between the 7th and 12th centuries. A mere bibliography +of the very considerable literature which exists in discussion of who, +where, and at what time the author was, would fill pages. Those who are +interested may obtain a start upon such references from Hermann Kopp's +_Beiträge zur Geschichte der Chemie_, Braunschweig, 1875, and in John +Ferguson's _Bibliotheca Chemica_, Glasgow, 1906. Berthelot, in his +_Chimie au Moyen Age_, Paris, 1893, considers the works under the name +of Geber were not in the main of Arabic origin, but composed by some +Latin scholar in the 13th century. In any event, certain works were, +under this name, printed in Latin as early as 1470-80, and have passed +innumerable editions since. They were first translated into English by +Richard Russell, London, 1678, and we have relied upon this and the +Nuremberg edition in Latin of 1541. This work, even assuming Berthelot's +view, is one of the most important in the history of chemistry and +metallurgy, and is characterised by a directness of statement unique +among alchemists. The making of the mineral acids--certainly nitric and +_aqua regia_, and perhaps hydrochloric and sulphuric--are here first +described. The author was familiar with saltpetre, sal-ammoniac, and +alkali, and with the acids he prepared many salts for the first time. He +was familiar with amalgamation, cupellation, the separation of gold and +silver by cementation with salt and by nitric acid. His views on the +primary composition of bodies dominated the alchemistic world for +centuries. He contended that all metals were composed of "spiritual" +sulphur (or arsenic, which he seems to consider a special form of +sulphur) and quicksilver, varying proportions and qualities yielding +different metals. The more the quicksilver, the more "perfect" the +metal. + +Albertus Magnus (Albert von Bollstadt) was a Dominican Monk, afterwards +Bishop, born about 1205, and died about 1280. He was rated the most +learned man of his time, and evidence of his literary activities lies in +the complete edition of his works issued by Pierre Jammy, Lyons, 1651, +which comprises 21 folio volumes. However, there is little doubt that a +great number of works attributed to him, especially upon alchemy, are +spurious. He covered a wide range of theology, logic, alchemy, and +natural science, and of the latter the following works which concern our +subject are considered genuine:--_De Rebus Metallicis et Mineralibus_, +_De Generatione et Corruptione_, and _De Meteoris_. They are little more +than compilations and expositions of the classics muddled with the +writings of the Arabs, and in general an attempt to conciliate the +Peripatetic and Alchemistic schools. His position in the history of +science has been greatly over-estimated. However, his mineralogy is, +except for books on gems, the only writing of any consequence at all on +the subject between Pliny and Agricola, and while there are but two or +three minerals mentioned which are not to be found in the ancient +authors, this work, nevertheless, deserves some place in the history of +science, especially as some attempt at classification is made. Agricola +devotes some thousands of words to the refutation of his "errors." + +Roger Bacon (1214-1294) was a Franciscan Friar, a lecturer at Oxford, +and a man of considerable scientific attainments for his time. He was +the author of a large number of mathematical, philosophical, and +alchemistic treatises. The latter are of some importance in the history +of chemistry, but have only minute bearing upon metallurgy, and this +chiefly as being one of the earliest to mention saltpetre. + +Basil Valentine is the reputed author of a number of alchemistic works, +of which none appeared in print until early in the 17th century. +Internal evidence seems to indicate that the "Triumphant Chariot of +Antimony" is the only one which may possibly be authentic, and could not +have been written prior to the end of the 15th or early 16th century, +although it has been variously placed as early as 1350. To this work has +been accredited the first mention of sulphuric and hydrochloric acid, +the separation of gold and silver by the use of antimony (sulphide), the +reduction of the antimony sulphide to the metal, the extraction of +copper by the precipitation of the sulphate with iron, and the discovery +of various antimonial salts. At the time of the publication of works +ascribed to Valentine practically all these things were well known, and +had been previously described. We are, therefore, in much doubt as to +whether this author really deserves any notice in the history of +metallurgy. + +EARLY 16th CENTURY WORKS.--During the 16th century, and prior to _De Re +Metallica_, there are only three works of importance from the point of +view of mining technology--the _Nützlich Bergbüchlin_, the +_Probierbüchlein_, and Biringuccio's _De La Pirotechnia_. There are also +some minor works by the alchemists of some interest for isolated +statements, particularly those of Paracelsus. The three works mentioned, +however, represent such a stride of advance over anything previous, +that they merit careful consideration. + +_Eyn Nützlich Bergbüchlin._ Under this title we frequently refer to a +little booklet on veins and ores, published at the beginning of the 16th +century. The title page of our copy is as below:-- + +[Illustration 610 (Title page)] + +This book is small 8vo, comprises 24 folios without pagination, and has +no typographical indications upon the title page, but the last line in +the book reads: _Gedruckt zu Erffurd durch Johan Loersfelt, 1527_. +Another edition in our possession, that of "Frankfurt am Meyn", 1533, by +Christian Egenolph, is entitled _Bergwerk und Probierbüchlin_, etc., and +contains, besides the above, an extract and plates from the +_Probierbüchlein_ (referred to later on), and a few recipes for assay +tests. All of these booklets, of which we find mention, comprise +instructions from Daniel, a skilled miner, to Knappius, "his mining +boy". Although the little books of this title are all anonymous, we are +convinced, largely from the statement in the Preface of _De Re +Metallica_, that one Calbus of Freiberg was the original author of this +work. Agricola says: "Two books have been written in our tongue: the one +on the assaying of mineral substances and metals, somewhat confused, +whose author is unknown; the other 'On Veins', of which Pandulfus Anglus +is also said to have written, _although the German book was written by +Calbus of Freiberg, a well-known doctor; but neither of them +accomplished the task he had begun_." He again refers to Calbus at the +end of Book III.[2] of _De Re Metallica_, and gives an almost verbatim +quotation from the _Nützlich Bergbüchlin_. Jacobi[3] says: "Calbus +Fribergius, so called by Agricola himself, is certainly no other than +the Freiberg doctor, Rühlein von C(K)albe." There are also certain +internal evidences that support Agricola's statement, for the work was +evidently written in Meissen, and the statement of Agricola that the +book was unfinished is borne out by a short dialogue at the end of the +earlier editions, designed to introduce further discussion. Calbus (or +Dr. Ulrich Rühlein von Kalbe) was a very active citizen of Freiberg, +having been a town councillor in 1509, burgomaster in 1514, a +mathematician, mining surveyor, founder of a school of liberal arts, and +in general a physician. He died in 1523.[4] The book possesses great +literary interest, as it is, so far as we are aware, undoubtedly the +first work on mining geology, and in consequence we have spent some +effort in endeavour to find the date of its first appearance. Through +the courtesy of M. Polain, who has carefully examined for us the +_Nützlich Bergbüchlein_ described in Marie Pellechet's _Catalogue +Général des Incunables des Bibliothèques Publiques de France_,[5] we +have ascertained that it is similar as regards text and woodcuts to the +Erfurt edition, 1527. This copy in the Bibliothèque Nationale is without +typographical indications, and M. Polain considers it very possible that +it is the original edition printed at the end of the fifteenth or +beginning of the sixteenth centuries. Mr. Bennett Brough,[6] quoting +Hans von Dechen,[7] states that the first edition was printed at +Augsburg in 1505, no copy of which seems to be extant. The Librarian at +the School of Mines at Freiberg has kindly furnished us with the +following notes as to the titles of the copies in that Institution:--(1) +_Eyn Wolgeordent und Nützlich Bergbüchlein_, etc., Worms, 1512[8] and +1518[9] (the place and date are written in), (2) the same as ours +(1527); (3) the same, Heinrich Steyner, Augsburg, 1534; (4) the same, +1539. On comparing these various editions (to which may be added one +probably published in Nürnberg by Friedrich Peypus in 1532[10]) we find +that they fall into two very distinct groups, characterised by their +contents and by two entirely different sets of woodcuts. + +Group I. + + (_a_) _Eyn Nützlich Bergbüchlein_ (in _Bibl. Nat._, Paris) + before 1500 (?). + + (_b_) Ditto, Erfurt, 1527. + +Group II. + + (_c_) _Wolgeordent Nützlich Bergbüchlein_, Worms, Peter + Schöfern, 1512. + + (_d_) _Wolgeordent Nützlich Bergbüchlein_, Worms, Peter + Schöfern, 1518. + + (_e_) _Bergbüchlin von Erkantnus der Berckwerck_, Nürnberg, + undated, 1532 (?). + + (_f_) _Bergwerckbuch & Probirbuch_, Christian Egenolph, + Frankfurt-am-Meyn, 1533. + + (_g_) _Wolgeordent Nützlich Bergbüchlein_, Augsburg, Heinrich + Steyner, 1534. + + (_h_) _Wolgeordent Nützlich Bergbüchlein_, Augsburg, Heinrich + Steyner, 1539. + +There are also others of later date toward the end of the sixteenth +century. + +The _Büchlein_ of Group I. terminate after the short dialogue between +Daniel and Knappius with the words: _Mitt welchen das kleinspeissig ertz +geschmeltzt soil werden_; whereas in those of Group II. these words are +followed by a short explanation of the signs used in the woodcuts, and +by directions for colouring the woodcuts, and in some cases by several +pages containing definitions of some 92 mining terms. In the editions of +Group I. the woodcut on the title page represents a miner hewing ore in +a vein and two others working a windlass. In those of Group II. the +woodcut on the title page represents one miner hewing on the surface, +another to the right carting away ore in a handcart, and two others +carrying between them a heavy timber. In our opinion Group I. represents +the older and original work of Calbus; but as we have not seen the copy +in the _Bibliothèque Nationale_, and the Augsburg edition of 1505 has +only so far been traced to Veith's catalogue,[11] the question of the +first edition cannot be considered settled at present. In any event, it +appears that the material grafted on in the second group was later, and +by various authors. + +The earliest books comprise ten chapters, in which Daniel delivers about +6,000 words of instruction. The first four chapters are devoted to the +description of veins and the origin of the metals, of the remaining six +chapters one each to silver, gold, tin, copper, iron, lead, and +quicksilver. Among the mining terms are explained the meaning of country +rock (_zechstein_), hanging and footwalls (_hangends_ and _liegends_), +the strike (_streichen_), dip (_fallen_), and outcrop (_ausgehen_). Of +the latter two varieties are given, one of the "whole vein," the other +of the _gesteins_, which may be the ore-shoot. Various veins are +illustrated, and also for the first time a mining compass. The account +of the origin of the metals is a muddle of the Peripatetics, the +alchemists, and the astrologers, for which acknowledgment to Albertus +Magnus is given. They are represented to originate from quicksilver and +sulphur through heat, cold, dampness, and dryness, and are drawn out as +exhalations through the veins, each metal owing its origin to the +special influence of some planet; the Moon for silver, Saturn for lead, +etc. Two types of veins are mentioned, "standing" (_stehendergang_) and +flat (_flachgang_). Stringers are given the same characteristics as +veins, but divided into hanging, footwall, and other varieties. +Prominence is also given to the _geschick_ (selvage seams or joints?). +The importance of the bearing of the junctions of veins and stringers +on enrichment is elaborated upon, and veins of east-west strike lying +upon a south slope are considered the best. From the following notes it +will be seen that two or three other types of deposits besides veins are +referred to. + +In describing silver veins, of peculiar interest is the mention of the +association of bismuth (_wismuth_), this being, we believe, the first +mention of that metal, galena (_glantz_), quartz (_quertz_), spar +(_spar_), hornstone (_hornstein_), ironstone and pyrites (_kies_), are +mentioned as gangue materials, "according to the mingling of the various +vapours." The term _glasertz_ is used, but it is difficult to say if +silver glance is meant; if so, it is the first mention of this mineral. +So far as we know, this is the first use of any of the terms in print. +Gold alluvial is described, part of the gold being assumed as generated +in the gravel. The best alluvial is in streams running east and west. +The association of gold with pyrites is mentioned, and the pyrites is +found "in some places as a complete stratum carried through +horizontally, and is called a _schwebender gang_." This sort of +occurrence is not considered very good "because the work of the heavens +can be but little completed on account of the unsuitability of the +position." Gold pyrites that comes in veins is better. Tin is mentioned +as found in alluvial, and also in veins, the latter being better or +worse, according to the amount of pyrites, although the latter can be +burned off. Tin-stone is found in masses, copper ore in schist and in +veins sometimes with pyrites. The ore from veins is better than schist. +Iron ore is found in masses, and sometimes in veins; the latter is the +best. "The iron veins with good hanging- and foot-walls are not to be +despised, especially if their strike be from east to west, their dip to +the south, the foot-wall and outcrop to the north, then if the ironstone +is followed down, the vein usually reveals gold or other valuable ore". +Lead ore is found in _schwebenden gang_ and _stehenden gang_. +Quicksilver, like other ore, is sometimes found in brown earth, and +sometimes, again, in caves where it has run out like water. The +classification of veins is the same as in _De Re Metallica_.[12] The +book generally, however, seems to have raised Agricola's opposition, for +the quotations are given in order to be demolished. + +_Probierbüchlein._ Agricola refers in the Preface of _De Re Metallica_ +to a work in German on assaying and refining metals, and it is our +belief that it was to some one of the little assay books published early +in the 16th century. There are several of them, seemingly revised +editions of each other; in the early ones no author's name appears, +although among the later editions various names appear on the title +page. An examination of these little books discloses the fact that their +main contents are identical, for they are really collections of recipes +after the order of cookery books, and intended rather to refresh the +memory of those already skilled than to instruct the novice. The books +appear to have grown by accretions from many sources, for a large number +of methods are given over and over again in the same book with slight +variations. We reproduce the title page of our earliest copy. + +[Illustration 612 (Title page)] + +The following is a list of these booklets so far as we have been able to +discover actual copies:-- + + _Date._ _Place._ _Publisher._ _Title (Short)._ _Author._ + + Unknown Unknown Unknown _Probierbüchlein_ Anon. + (Undated; but catalogue of British Museum suggests Augsburg, 1510.) + + 1524 Magdeburg _Probirbüchleyn Anon. + tzu Gotteslob_ + + 1531 Augsburg Unknown _Probierbuch aller Anon. + Sachsischer Ertze_ + + 1533 Frankfurt a. _Bergwerck und Anon. + Meyn Probierbüchlein_ + + 1534 Augsburg Heinrich _Probirbüchlein_ Anon. + Steyner, 8vo. + + 1546 Augsburg Ditto, ditto _Probirbüchlein_ Anon. + + 1549 Augsburg Ditto, ditto _Probirbüchlein_ Anon. + + 1564 Augsburg Math. Francke, _Probirbüchlein_ Zach. Lochner + 4to + + 1573 Augsburg 8vo. _Probirbuch_ Sam. Zimmermann + + 1574 Franckfurt _Probierbüchlein_ Anon. + a. Meyn + + 1578 Ditto _Probierbüchlein Fremde Cyriacus + und subtile Kunst_ Schreittmann + + 1580 Ditto _Probierbüchlein_ Anon. + + 1595 Ditto _Probierbüchlein darinn Modestin Fachs + gründlicher Bericht_ + + 1607 Dresden 4to _Metallische Probier C. C. Schindler + Kunst_ + _Bericht vom Ursprung und + Erkenntniss der + Metallischen erze_ + + 1669 Amsterdam _Probierbüchlein darinn Modestin Fachs + gründlicher Bericht_ + + 1678 Leipzig _Probierbüchlein darinn Modestin Fachs + gründlicher Bericht_ + + 1689 Leipzig _Probierbüchlein darinn Modestin Fachs + gründlicher Bericht_ + + 1695 Nürnberg 12mo. _Deutliche Vorstellung Anon. + der Probier Kunst_ + + 1744 Lübeck 8vo. _Neu-eröffnete Probier Anon. + Buch_ + + 1755 Frankfurt 8vo. _Scheid-Künstler ... Anon. + and Leipzig alle Ertz und Metalle + ... probiren_ + + 1782 Rotenburg an 8vo. _Probierbuch aus K. A. Scheidt + der Fulde Erfahrung aufgesetzt_ + +As mentioned under the _Nützlich Bergbüchlein_, our copy of that work, +printed in 1533, contains only a portion of the _Probierbüchlein_. +Ferguson[13] mentions an edition of 1608, and the Freiberg School of +Mines Catalogue gives also Frankfort, 1608, and Nürnberg, 1706. The +British Museum copy of earliest date, like the title page reproduced, +contains no date. The title page woodcut, however, in the Museum copy is +referred from that above, possibly indicating an earlier date of the +Museum copy. + +The booklets enumerated above vary a great deal in contents, the +successive prints representing a sort of growth by accretion. The first +portion of our earliest edition is devoted to weights, in which the +system of "lesser weights" (the principle of the "assay ton") is +explained. Following this are exhaustive lists of touch-needles of +various composition. Directions are given with regard to assay furnaces, +cupels, muffles, scorifiers, and crucibles, granulated and leaf metals, +for washing, roasting, and the preparation of assay charges. Various +reagents, including glass-gall, litharge, salt, iron filings, lead, +"alkali", talc, argol, saltpetre, sal-ammoniac, alum, vitriol, lime, +sulphur, antimony, _aqua fortis_, or _scheidwasser_, etc., are made use +of. Various assays are described and directions given for crucible, +scorification, and cupellation tests. The latter part of the book is +devoted to the refining and parting of precious metals. Instructions are +given for the separation of silver from iron, from lead, and from +antimony; of gold from silver with antimony (sulphide) and sulphur, or +with sulphur alone, with "_scheidwasser_," and by cementation with salt; +of gold from copper with sulphur and with lead. The amalgamation of gold +and silver is mentioned. + +The book is diffuse and confused, and without arrangement or system, +yet a little consideration enables one of experience to understand most +statements. There are over 120 recipes, with, as said before, much +repetition; for instance, the parting of gold and silver by use of +sulphur is given eight times in different places. The final line of the +book is: "Take this in good part, dear reader, after it, please God, +there will be a better." In truth, however, there are books on assaying +four centuries younger that are worse. This is, without doubt, the first +written word on assaying, and it displays that art already full grown, +so far as concerns gold and silver, and to some extent copper and lead; +for if we eliminate the words dependent on the atomic theory from modern +works on dry assaying, there has been but very minor progress. The art +could not, however, have reached this advanced stage but by slow +accretion, and no doubt this collection of recipes had been handed from +father to son long before the 16th century. It is of wider interest that +these booklets represent the first milestone on the road to quantitative +analysis, and in this light they have been largely ignored by the +historians of chemistry. Internal evidence in Book VII. of _De Re +Metallica_, together with the reference in the Preface, leave little +doubt that Agricola was familiar with these booklets. His work, however, +is arranged more systematically, each operation stated more clearly, +with more detail and fresh items; and further, he gives methods of +determining copper and lead which are but minutely touched upon in the +_Probierbüchlein_, while the directions as to tin, bismuth, quicksilver, +and iron are entirely new. + +Biringuccio (Vanuccio). We practically know nothing about this author. +From the preface to the first edition of his work it appears he was +styled a mathematician, but in the text[14] he certainly states that he +was most of his time engaged in metallurgical operations, and that in +pursuit of such knowledge he had visited Germany. The work was in +Italian, published at Venice in 1540, the title page of the first +edition as below:-- + +[Illustration 614 (Title page)] + +It comprises ten chapters in 168 folios demi-octavo. Other Italian +editions of which we find some record are the second at Venice, 1552; +third, Venice, 1558; fourth, Venice, 1559; fifth, Bologna, 1678. A +French translation, by Jacques Vincent, was published in Paris, 1556, +and this translation was again published at Rouen in 1627. Of the ten +chapters the last six are almost wholly devoted to metal working and +founding, and it is more largely for this description of the methods of +making artillery, munitions of war and bells that the book is +celebrated. In any event, with the exception of a quotation which we +give on page 297 on silver amalgamation, there is little of interest on +our subject in the latter chapters. The first four chapters are +undoubtedly of importance in the history of metallurgical literature, +and represent the first work on smelting. The descriptions are, however, +very diffuse, difficult to follow, and lack arrangement and detail. But +like the _Probierbüchlein_, the fact that it was written prior to _De Re +Metallica_ demands attention for it which it would not otherwise +receive. The ores of gold, silver, copper, lead, tin, and iron are +described, but much interrupted with denunciations of the alchemists. +There is little of geological or mineralogical interest, he too holding +to a muddle of the classic elements astrology and alchemy. He has +nothing of consequence to say on mining, and dismisses concentration +with a few words. Upon assaying his work is not so useful as the +_Probierbüchlein_. On ore smelting he describes the reduction of iron +and lead ores and cupriferous silver or gold ores with lead. He gives +the barest description of a blast furnace, but adds an interesting +account of a _reverbero_ furnace. He describes liquation as consisting +of one operation; the subsequent treatment of the copper by refining +with an oxidizing blast, but does not mention poling; the cupellation of +argentiferous lead and the reduction of the litharge; the manufacture of +nitric acid and that method of parting gold and silver. He also gives +the method of parting with antimony and sulphur, and by cementation with +common salt. Among the side issues, he describes the method of making +brass with calamine; of making steel; of distilling quicksilver; of +melting out sulphur; of making vitriol and alum. He states that +_arsenico_ and _orpimento_ and _etrisagallio_ (realgar) are the same +substance, and are used to colour copper white. + +In general, Biringuccio should be accredited with the first description +(as far as we are aware) of silver amalgamation, of a reverberatory +furnace, and of liquation, although the description is not complete. +Also he is, so far as we are aware, the first to mention cobalt blue +(_Zaffre_) and manganese, although he classed them as "half" metals. His +descriptions are far inferior to Agricola's; they do not compass +anything like the same range of metallurgy, and betray the lack of a +logical mind. + +_Other works._ There are several works devoted to mineralogy, dating +from the fifteenth and early sixteenth centuries, which were, no doubt, +available to Agricola in the compilation of his _De Natura Fossilium_. +They are, however, practically all compiled from the jeweller's point of +view rather than from that of the miner. Among them we may mention the +poem on precious stones by Marbodaeus, an author who lived from 1035 to +1123, but which was first printed at Vienna in 1511; _Speculum Lapidum_, +a work on precious stones, by Camilli Leonardi, first printed in Venice +in 1502. A work of wider interest to mineralogists is that by Christoph +Entzelt (or Enzelius, Encelio, Encelius, as it is variously given), +entitled _De Re Metallica_, and first printed in 1551. The work is five +years later than _De Natura Fossilium_, but contains much new material +and was available to Agricola prior to his revised editions. + + +FOOTNOTES: + +[1] See pages 44 and 46. + +[2] Page 75. + +[3] _Der Mineralog Georgius Agricola_, Zwickau, 1889, p. 46. + +[4] Andreas Möller, _Theatrum Freibergense Chronicum_, etc., Freiberg, +1653. + +[5] Paris, 1897, Vol. I. p. 501. + +[6] Cantor Lectures, London, April 1892. + +[7] Hans von Dechen, _Das älteste deutsche Bergwerksbuch_, reprint from +_Zts. für Bergrecht Bd. XXVI._, Bonn, 1885. + +[8] Panzer's _Annalen_, Nürnberg, 1782, p. 422, gives an edition Worms +_bei_ Peter Schöfern, 1512. + +[9] The Royal Library at Dresden and the State Library at Munich have +each a copy, dated 1518, Worms. + +[10] Hans von Decken _op. cit._, p. 48-49. + +[11] _Annales typographiae augustanae ab ejus origine, MCCCLXVI. usque +ad. an. M.D.XXX. Accedit dom Franc. Ant. Veith. Diatribe de origine ... +artis typographicae in urbe augusta vindelica edidit...._ Georgius G. +Zapf., Augsburg, 1778, X. p. 23. + +[12] See p. 44. + +[13] _Bibliotheca Chemica_. + +[14] Book I., Chap. 2. + + + + +APPENDIX C. + +WEIGHTS AND MEASURES. + + +As stated in the preface, the nomenclature to be adopted for weights and +measures has presented great difficulty. Agricola uses, throughout, the +Roman and the Romanized Greek scales, but in many cases he uses these +terms merely as lingual equivalents for the German quantities of his +day. Moreover the classic language sometimes failed him, whereupon he +coined new Latin terms adapted from the Roman scale, and thus added +further confusion. We can, perhaps, make the matter clearer by an +illustration of a case in weights. The Roman _centumpondium_, composed +of 100 _librae_, the old German _centner_ of 100 _pfundt_, and the +English hundredweight of 112 pounds can be called lingual equivalents. +The first weighs about 494,600 Troy grains, the second 721,900, and the +third 784,000. While the divisions of the _centumpondium_ and the +_centner_ are the same, the _libra_ is divided into 12 _unciae_ and the +_pfundt_ into 16 _untzen_, and in most places a summation of the units +given proves that the author had in mind the Roman ratios. However, on +p. 509 he makes the direct statement that the _centumpondium_ weighs 146 +_librae_, which would be about the correct weight if the _centumpondium_ +referred to was a _centner_. If we take an example such as "each +_centumpondium_ of lead contains one _uncia_ of silver", and reduce it +according to purely lingual equivalents, we should find that it runs +24.3 Troy ounces per short ton, on the basis of Roman values, and 18.25 +ounces per short ton, on the basis of old German. If we were to +translate these into English lingual equivalents of one ounce per +hundredweight, then the value would be 17.9 ounces per short ton. + +Several possibilities were open in translation: first, to calculate the +values accurately in the English units; second, to adopt the nearest +English lingual equivalent; third, to introduce the German scale of the +period; or, fourth, to leave the original Latin in the text. The first +would lead to an indefinite number of decimals and to constant doubt as +to whether the values, upon which calculations were to be based, were +Roman or German. The second, that is the substitution of lingual +equivalents, is objectionable, not only because it would indicate values +not meant by the author, but also because we should have, like Agricola, +to coin new terms to accommodate the lapses in the scales, or again to +use decimals. In the third case, that is in the use of the old German +scale, while it would be easier to adapt than the English, it would be +more unfamiliar to most readers than the Latin, and not so expressive in +print, and further, in some cases would present the same difficulties of +calculation as in using the English scale. Nor does the contemporary +German translation of _De Re Metallica_ prove of help, for its +translator adopted only lingual equivalents, and in consequence the +summation of his weights often gives incorrect results. From all these +possibilities we have chosen the fourth, that is simply to reproduce the +Latin terms for both weights and measures. We have introduced into the +footnotes such reductions to the English scale as we considered would +interest readers. We have, however, digressed from the rule in two +cases, in the adoption of "foot" for the Latin _pes_, and "fathom" for +_passus_. Apart from the fact that these were not cases where accuracy +is involved, Agricola himself explains (p. 77) that he means the German +values for these particular terms, which, fortunately, fairly closely +approximate to the English. Further, we have adopted the Anglicized +words "digit", "palm", and "cubit", instead of their Latin forms. + +For purposes of reference, we reproduce the principal Roman and old +German scales, in so far as they are used by Agricola in this work, with +their values in English. All students of weights and measures will +realize that these values are but approximate, and that this is not an +occasion to enter upon a discussion of the variations in different +periods or by different authorities. Agricola himself is the author of +one of the standard works on Ancient Weights and Measures (see Appendix +A), and further gives fairly complete information on contemporary scales +of weight and fineness for precious metals in Book VII. p. 262 etc., to +which we refer readers. + + ROMAN SCALES OF WEIGHTS. + + Troy Grains. + 1 _Siliqua_ = 2.87 + 6 _Siliquae_ = 1 _Scripulum_ 17.2 + 4 _Scripula_ = 1 _Sextula_ 68.7 + 6 _Sextulae_ = 1 _Uncia_ 412.2 + 12 _Unciae_ = 1 _Libra_ 4946.4 + 100 _Librae_ = 1 _Centumpondium_ 494640.0 + + Also + + 1 _Scripulum_ = 17.2 + 3 _Scripula_ = 1 _Drachma_ 51.5 + 2 _Drachmae_ = 1 _Sicilicus_ 103.0 + 4 _Sicilici_ = 1 _Uncia_ 412.2 + 8 _Unciae_ = 1 _Bes_ 3297.6 + + SCALE OF FINENESS + (AGRICOLA'S ADAPTATION). + + 4 _Siliquae_ = 1 Unit of _Siliquae_ + 3 _Units of Siliquae_ = 1 _Semi-sextula_ + 4 _Semi-sextulae_ = 1 _Duella_ + 24 _Duellae_ = 1 _Bes_ + + OLD GERMAN SCALE OF WEIGHTS. + Troy Grains. + 1 _Pfennig_ = 14.1 + 4 _Pfennige_ = 1 _Quintlein_ 56.4 + 4 _Quintlein_ = 1 _Loth_ 225.6 + 2 _Loth_ = 1 _Untzen_ 451.2 + 8 _Untzen_ = 1 _Mark_ 3609.6 + 2 _Mark_ = 1 _Pfundt_ 7219.2 + 100 _Pfundt_ = 1 _Centner_ 721920.0 + + SCALE OF FINENESS. + + 3 _Grenlin_ = 1 _Gran_ + 4 _Gran_ = 1 _Krat_ + 24 _Krat_ = 1 _Mark_ + + ROMAN LONG MEASURE. + Inches. + 1 _Digitus_ = .726 + 4 _Digiti_ = 1 _Palmus_ 2.90 + 4 _Palmi_ = 1 _Pes_ 11.61 + 1-1/2 _Pedes_ = 1 _Cubitus_ 17.41 + 5 _Pedes_ = 1 _Passus_ 58.1 + + Also + + 1 Roman _Uncia_ = .97 + 12 _Unciae_ = Pes 11.61 + + GREEK LONG MEASURE. + Inches. + 1 _Dactylos_ = .758 + 4 _Dactyloi_ = 1 _Palaiste_ 3.03 + 4 _Palaistai_ = 1 _Pous_ 12.135 + 1-1/2 _Pous_ = 1 _Pechus_ 18.20 + 6 _Pous_ = 1 _Orguia_ 72.81 + + OLD GERMAN LONG MEASURE. + Inches. + 1 _Querfinger_ = .703 + 16 _Querfinger_ = 1 _Werckschuh_ 11.247 + 2 _Werckschuh_ = 1 _Elle_ 22.494 + 3 _Elle_ = 1 _Lachter_ 67.518 + + Also + + 1 _Zoll_ = .85 + 12 _Zoll_ = 1 _Werkschuh_ + + ROMAN LIQUID MEASURE. + Cubic inches. Pints. + 1 _Quartarius_ = 8.6 .247 + 4 _Quartarii_ = 1 _Sextarius_ 31.4 .991 + 6 _Sextarii_ = 1 _Congius_ 206.4 5.947 + 16 _Sextarii_ = 1 _Modius_ 550.4 15.867 + 8 _Congii_ = 1 _Amphora_ 1650.0 47.577 + + (Agricola nowhere uses the Saxon liquid measures, nor do they + fall into units comparable with the Roman). + + + + +GENERAL INDEX. + +NOTE.--The numbers in heavy type refer to the Text; those in plain type +to the Footnotes, Appendices, etc. + + + Abandonment of Mines, =217= + + Abertham. + Mines at, =74=; =92=; 74 + + Abolite, 113 + + _Abstrich_, 465; 492 + + Abydos. + Gold mines of, =26=; 27 + Lead figure from, 390 + + _Abzug_, 464; 465; 475 + + _Achates_ (_see_ Agate). + + Accidents To Miners, =214-218= + + Accounts (Mining), =96-98= + + Adit, 101 + + _Aeris flos_ (_see_ Copper Flowers). + + _Aeris squama_ (_see_ Copper Scales). + + _Aes caldarium_, 109 + + _Aes luteum_, 109 + + _Aes nigrum_, 109 + + _Aes purum fossile_ (_see_ Native Copper). + + _Aes rude plumbei coloris_ (_see_ Copper Glance). + + _Aes ustum_ (_see_ Roasted Copper). + + _Aetites_, 2 + + Africa. + Iron, 420 + Tin, 412 + + Agate, 114 + + Agriculture. + Mining compared with, =5= + + Ailments of Miners (_see_ Maladies of Miners). + + Air Currents in Mines, =121=; =200= + + Alabaster, 114 + + Alchemists, XXVII-XXX; 44; 608 + Agricola's opinion of, XII; =XXVII.= + Amalgamation, 297 + Assaying, =248=; 219 + Discovery of acids, 439; 460 + Distillation, 441 + + Aljustrel Tablet, 83-84 + + Alkali, 558 + + Alloys, Assaying of, =247-252= + + Alluvial Mining, =321-348=; 330-332 + + Alston Moor, 84 + + Altenberg, =XXXI=; VI. + Collapse of mine, =216= + Miners poisoned, =214= + Tin working appliances, =290=; =304=; =318= + + Alum, =564-568=; 564-570 + A solidified juice, 1 + Elizabethan Charter, 283 + In roasted pyrites, =350= + In _Sal artificiosus_, =463= + Latin and German terms, 220; 221 + Papal monopoly, 570 + Use in making nitric acid, =439=; 460 + + Amalgam. + Parting the gold from, =298=; 297 + + Amalgamation, 297 + Of gilt objects, =461= + Mills, =295-299= + + Amber, =34=; 35 + + Amethyst, 114 + + _Amiantus_ (_see_ Asbestos). + + Ampulla, =445-447=; 220 + + Annaberg, VI; =XXXI=; =42=; =75=; 75 + Profits, =92= + + Ant, venomous, =216= + + Antimony, 220; 428; 354 + Minerals, 110 + Smelting of, =400=; =428= + Use as type-metal, 2; 429 + + Antimony Sulphide, 220; 428; 451 + Parting gold and silver with, =451=; 451; 461 + Parting gold from copper, =463= + Parting silver and iron, =544= + + Antwerp, Scale of Weights, =263= + + Apex Law, 81; 83-86 + + _Aqua regia_, 439; 441; 354 + + _Aqua valens_ (_see also_ Nitric Acid), =439-443=; 439; 220 + Clarification with silver, =443=; 443 + Cleansing gold-dust with, =396= + Parting precious metals with, =443-447= + + _Arbores dissectae_ (Lagging), 101 + + Archimedes, Screw of, 149 + + Architecture. + Knowledge necessary for miners, =4= + + _Area fodinarum_ (_see_ Meer). + + Argentiferous Copper Ores, Smelting of, =404-407= + + Argentite, 109 + + _Argentum purum in venis_ (_see_ Native Silver). + + _Argentum rude plumbei coloris_ (_see_ Silver Glance). + + _Argentum rude rubrum translucidum_ (_see_ Ruby Silver). + + Argol, 234; 220 + As a flux, =234=; =238=; =243= + Use in melting silver nitrate, =447= + Use in smelting gold dust, =396-398= + + Argonauts, 330 + + Arithmetical Science. + Knowledge necessary for miners, =4= + + Armenia, Stone of, 115 + + Arsenic (_see also_ Orpiment _and_ Realgar), 111; 214 + + _Arsenicum_, 111 + + Arsenopyrite, 111 + + Asbestos, =440=; 440; 114 + + Ash-coloured Copper, =539-540=; 540; 523-524; 492 + From liquation, =529-530= + + Ashes which Wool Dyers use (_see also_ Potash), 233; 559; 220 + Use in assaying, =236-238= + + Ash of Lead, =237-238=; 237; 220 + + Ash of Musk Ivy (_see also_ Potash and _Nitrum_), =236-238=; 220 + + Asphalt, 581 + + _Asphaltites_ (_see_ Dead Sea). + + Assay Balances (_see_ Balances). + + Assay Fluxes (_see_ Fluxes). + + Assay Furnaces, =224-228=; 220 + Crucible, =226-227= + Muffle, =224-228=; =239= + + Assaying (_see also_ _Probierbüchlein_), =219=; 219; 220; 354 + Amalgamation, =243= + Bismuth, =247= + Copper, =244= + Cupellation, =240= + Gold and silver alloys, =248= + Gold ore, =242-244= + Iron ore, =247= + Lead, =245-246= + Silver, =242-245= + Silver and copper alloys, =249-250= + Tin, =246= + Tin and silver alloys, =251= + + Assay Muffles (_see_ Muffles). + + Assay Ton, =261=; 242 + + Assyrian Copper, 402 + + Asthma, =214= + + Astronomy. + Knowledge necessary for miners, =4= + + Atarnea. + Mines near, =26=; 27 + + Athens. + Mining law, 83 + Sea power and mines, 27 + Silver mines (_see_ Mt. Laurion, Mines of). + + _Atramentum Sutorium_ (_see also_ Vitriol), 572; 110 + + _Atramentum Sutorium candidum_, 113 + + _Atramentum Sutorium rubrum_, =274=; 274 + + _Aurichalcum_, 409; 404 + + _Auripigmentum_ (_see_ Orpiment). + + Azure, 1; 109; 220 + An indication of copper, =116= + An indication of gold, =117= + Colour of flame, =235= + + Azurite 109; 220; 402 + + + Babel, Tower of, 582 + + Babylonia. + Bitumen in, 582 + Use of lead, 391 + + Babytace. + Gold buried by inhabitants, =9=; =15= + + Baebelo, =42=; 42 + + Balances, =224=; =264-265= + + Barite, 115 + + Barmaster, of High Peak, 77 + + Bars, for Furnace Work, =382= + + Baskets, for Hoisting, =153= + + Batea, =156= + + Beer, =230=; 220 + + Bell, to call Workmen, =100= + + Bellows, =362-373=; =419= + Ancient use of, 354; 355; 362 + Assay furnace, =226=; =245= + Mine ventilation with, =207-210= + + Beni Hassen, Inscriptions at, 586 + + _Berg-geel_, 111 + + Bergmeister, =33=; =81=; =95=; =77=; 77; 78 + Deals with forfeited shares, =92-93= + Jurors, =96= + + Bergmeister's Clerk, =95=; 78 + + _Bergzinober_ (_see_ Quicksilver). + + Bermius (Bermium), Mt. (_see_ Mt. Bermius). + + Bismuth, =433=; 354; 220 + Assaying ores of, =247= + Indication of silver, =116= + Minerals, 2; 111 + Smelting of, =433-437=; =400= + The "roof of silver," =117=; 433 + _Zaffre_, 112 + + Bitumen. + Ancient knowledge of, 220; 581-582; 354 + Colour of fumes, =235= + Dead Sea, =33= + Distillation, =581= + From springs, =582= + Harmful to metals, =273= + Roasting from ore, =273=; =276=; =351= + Solidified juice, =1= + + _Bituminosa cadmia_ (_see_ _Cadmia bituminosa_). + + Blast, Regulation of, =380=; =386= + + Blasting, 119 + + Blende, 113 + + Bleyberg, 239 + + Bloodstone, 111; 2 + + Bloom, 420 + + _Blütstein_ (_see_ Ironstone). + + Bohemia. + Antimony sulphide, 428 + Pestilential vapours, =216= + Sifting ore in, =293= + Smelting, =384= + + Bone-ash, =230=; 466 + + Borax, 560; 221; 110 + Method of manufacture, =560= + Use in gold smelting, =444=; =457=; =464= + Use in assaying, =245=; =246= + + Bornite, 109 + + Boundary Stones, =87=; 129 + + Boundaries, =77=; =147= + + Bowls for Alluvial Washing, =322=; =324=; =334=; =336= + + Brass, 410; 354; 2 + Ancient methods of making, 404-405; 112 + + Breaking Ore, =117-119= + + Brick Dust. + Used in cementation, =454=; 454 + Used in making nitric acid, =440= + + Brine (_see also_ Salt). + Evaporation of, =547-548= + + Britain. + Lead-silver smelting, 392 + Miners mentioned by Pliny, 83 + Tin trade, 411-413 + + British Museum. + Egyptian gold-mining, 399 + Egyptian lead, 390 + Egyptian steel, 402 + + Bromyrite, 109 + + Bronze. + Historical notes, 411; 402; 354 + + Bronze Age, 355; =402=; 411 + + Bryle (Outcrop), 101 + + Buckets, for Hoisting Ore, =153-154=; =157= + + Buddle, 281; 282; 267 + Divided, =302-303= + Simple, =300-302=; =312-315= + + Bullion, Pouring into Bars, =382= + + Burning Ore, =231=; =273=; 267 + + Burnt Alum, =233=; 565; 221 + + + _Cadmia_ (_see also_ Zinc, _Pompholyx_, _and_ Cobalt), =542=; 542; + 112-113 + Ancient ore of brass, 410 + From dust chambers, =394= + From liquation, =539=; 542 + From roasting matte, =349= + Poisonous to miners, =214=; 214 + Roasting, =276= + Smelting for gold and silver, =410= + + _Cadmia bituminosa_, =276=; 273; 113 + + _Cadmia fornacis_ (_see_ Furnace Accretions). + + _Cadmia fossilis_ (_see_ Calamine _and_ Blende). + + _Cadmia metallica_ (_see also_ Cobalt), =403=; 113 + + _Caeruleum_ (_see_ Azure). + + Cakes of Melted Pyrites, 379; 222 + A flux, =234= + Roasting of, =349-351= + Use in smelting, =379= + + Calaëm (_see also_ Zinc), =409= + + Calamine, 112; 113; 409; 410 + + Calcite, 114 + + Calcspar, =116=; 114 + + _Caldarium_ Copper, =512=; =542=; 404; 511 + + Caldrons, for Evaporating Salts, =548= + + _Calmei_ (_see_ Calamine). + + Cameros. + Zinc found at, 409 + + Camphor, =238=; 238; 221 + + Cam-shaft, =282-283=; 267 + + _Canales_ (Ore Channels), 43; 46; 47 + Ore shoots in, =117= + + Cannon, =11= + + Cardinal Points, =57=; =58= + + Carnelian, 114 + + _Carneol_ (_see_ Carnelian). + + _Carni_, 390 + Cupellation, =483= + Smelting of lead ores, =390= + + Carpathian Mountains. + Liquation practice in, =540=; =544= + Sieves, =289= + Stamp-milling, =319= + + Carthage. + Mines in Spain, =27= + + Castulo (Cazlona), 42 + + Cementation (_see also_ Parting Gold from Silver), =453-457=; 453; 458 + + _Centumpondium_, 616; 242; 509 + Scale of weights, =260-261= + + Cerargurite, 109 + + _Cerussa_ (_see_ White-lead). + + Cerussite, 110 + + Chain Pumps, =171-175= + + Chalcanthite, 110 + + _Chalcanthum_ (_see also_ Vitriol), 109; 572 + + Chalcedony, 114 + + _Chalcitis_, 573; 109 + Indication of copper, =116= + + Chalcocite, 109; 402 + + Chalcopyrite, 109 + + Chaldean Antimony, 429 + + Chemistry. + Origin, XXVII; 220 + + Chemnitz. + Agricola appointed city physician, VII. + Agricola elected burgomaster, VIII; IX. + Quarrel over Agricola's burial, XI. + + China, Grand Canal of, 129 + + Chinese. + Early copper smelting, 402 + Early iron, 421 + Early silver metallurgy, 391 + Early zinc smelting, 409 + + _Chrysocolla_ (_see also_ Borax), 110; 221; 584; 1 + Collection in vats, =584= + Colour of fumes, =235= + Indication of copper, =116= + Indication of gold, =117= + Mineral, 109 + Smelting of, =401= + + Church, Share in Mines, =91= + + Cimolite, 31 + + Cinnabar (_see_ Quicksilver _and_ _Minium_). + + Claim, in American Title, 77 + + Cloth. + Lining sluices, =322= + Ventilation by shaking, =210= + + Coal, 34 + + Cobalt, 354; 542; 112-113 + Cobalt-blue, 112; 433 + From lead smelting, 408 + King Hiram's experience with, 214 + Poisonous to miners, 214 + Relation to _cadmia_, 112 + Relation to bismuth, 435 + Smelting ores of, 401 + + Cobalt-Arsenic Minerals (_see_ Arsenic). + + Cobaltite, 113 + + _Cobaltum cineraceum_ (_see_ Smallite). + + _Cobaltum ferri colore_ (_see_ Cobaltite). + + _Cobaltum nigrum_ (_see_ Abolite). + + Coiners, =95=; 78 + + Coins, =251-253=; =457= + + Colchis. + Alluvial gold washing, =330= + + Cologne. + Scale of weights, =263= + + Companies, Mining, =89-93=; 90 + Fraudulent dealing, =22= + Investment in, =29= + + Compass, =141-142=; 56; 129 + Divisions of the, =56=; =57= + Swiss, =145=; 137 + + Concentrates. + From washing liquation products, =542= + Sintering of, =401= + Smelting of, =394=; =396-399=; =401= + + Concentration, =267-348=; 279; 354 + + _Congius_, 153; 172, 617 + + Constantinople, Alum Trade, 569 + + Consumption. + Miners liable to, =214= + + _Conterfei_ (_see_ Zinc). + + Contracts, Method of Setting, =96= + + Copiapite, 111 + + Copper (_see also_ Liquation), 109; 402; 511 + Assay of, =244=; =249= + Granulation of, =250= + Indications of, =116= + Parting from gold, =462-464= + Parting gold from silver, =448-451=; 448 + Ratio in liquation cakes, 505; 506 + Residues from liquation, =521= + Rosette, =538= + + Copper-filings, =233=; 233; 221 + + Copper flowers, =538=; 110; 233; 538 + Pliny's description, 404 + + Copper Glance, =401=; 109 + + Copper Matte. + Roasting, =350= + Smelting, =404-407= + + Copper Ore (_see also_ Copper Smelting, _etc._), 109 + Assaying, =244-245= + + Copper Pyrites, =117=; 109 + + Copper Refining, =530-538=; 354; 492; 535-536 + Breaking cakes, =501-503= + Enrichment of silver by settling, 510 + Roman method, 404 + Rosette copper, 535 + + Copper Scales, 110; 221; 233; 539 + Use in assaying, =245= + + Copper Schists (_see also_ Mannsfeld Copper Slates), 127 + Method of smelting, =408= + + Copper Smelting, =388-390=; =401=; =404=; 402 + Invention of appliances, 353-354 + + Cornwall. + Ancient tin mining, 413 + Early German miners, 282 + Early mining law, 85 + Early ore dressing, 282 + Influence on German mining, 283 + "Knockers," 217 + Mining terms, 77; 101; 267; 282 + Royal Geol. Soc. Transactions, 84 + + _Coticula_ (_see_ Touchstone). + + _Counterfeht_ (_see_ Zinc). + + Crane. + For cupellation furnaces, =476-477= + For lead cakes, =500= + For liquation cakes, =514= + + Cremnitz. + Age of mines, =5= + Width of veins, =52= + + Crinoid Stems, 115 + + Croppings, =37=; 37 + + Crosscuts, =106= + + Crowbars, =152= + + Crucible. + Assay, =228=; =230=; =241=; =245=; 221 + Of blast furnaces, =376=; =377= + + _Crudaria_, 65 + + Crushing Mills (_see_ Stamp-mill _and_ Mills). + + Crushing Ore, =231=; =279-287=; 279 + + Crystal (_Crystallum_), 114 + + Cumberland. + Early report on ores of, 267 + Roman lead furnaces, 392 + + Cup-Bearer. + Right to a meer, =81= + + Cupellation, =464-483=; 465-466 + Buildings and furnaces, =464-472=; 492 + Brightening of the silver, =241=, =475= + In assaying, =240= + In "tests," =483= + Latin and German terms, 221; 492 + Litharge, =475= + + Cupels, =228-230=; 221; 466 + Drying of, =240= + Moulds, =231= + + Cupric Oxide, 221 + + Cuprite, 109; 402 + + _Cyanus_ (_see also_ Azurite), 110 + + Cyprus. + Ancient copper smelting, 402 + + + _Dach_, 127 + + _Dactylos_, 617; 78 + + Dangers to Miners, =214-218= + + _Darrlinge_, 492 + + _Darrofen_, 492 + + _Darrsöhle_, 492 + + Dawling, of a Vein, 101 + + Dead Sea. + Bitumen in, =33= + + Decemviral College, =96= + + _Decumanus_ (_see_ Tithe Gatherer). + + _Demensum_ (_see_ Measure). + + Demons (_see also_ Gnomes), =217=; 217 + + Derbyshire (_see also_ High Peak). + Early ore washing, 281 + Introduction jigging sieve, 283 + Mining law, 77; 84-85 + + Descent into Mines, =212= + + Devon. + Mining law, 85 + + Dilleugher, 267 + + Dioptra, 129 + + _Diphrygum_, 404 + + Dip of Veins, =65-75= + + Dippas, 101 + + Dippers, =157= + Of pumps, =172= + + _Discretores_ (_see_ Sorters). + + Distillation, 441 + For making nitric acid, =441= + Of amalgam, =244= + Of quicksilver, =426-432= + + _Distributor_, 78 + + Divining Rod, =38-40=; 38; 40 + + Divisions of the Compass, =56=; =57= + + Drainage of Mines, =121=; =171-198= + With buckets, =171= + With chain pumps, =172= + With rag and chain pumps, =188= + With suction pumps, =172= + With water bags, =198= + + Drawing. + Knowledge necessary for miners, =4= + + Drifts, =104=; =105=; 101 + Timbering of, =125= + + Drusy Veins, =107=; 107 + + "Drying" Liquation Residues (_see also_ Liquation), =527-529=; 491; 492 + Furnaces for, =521=; =526=; 492 + Silver extracted by, =529= + Slags from, 523 + + Dumps, Working of, =30= + + Dust Chambers, =394=; =416=; 354 + + Dutins, (Timbers), 101 + + Dynamite, 119 + + + "Earths." + Agricola's view of, 1; 46; 48 + Extraordinary, =115= + Peripatetic view of, 46; 47 + + Egyptians. + Alluvial mining, 330 + Antimony, 428 + Bronze, 402; 411 + Copper smelting, 402 + Crushing and concentration, 279 + Furnaces, 355 + Glass making, 586 + Gold mining, 399 + Iron, 421 + Maps, 129 + Mining law, 83 + Silver and lead metallurgy, 390 + Tin, 411; 412 + + Egyptian Screw (_see_ Archimedes, Screw of). + + Eifel. + Spalling ore, =272= + + _Eisenertz_ (_see_ Ironstone). + + _Eisenglantz_ (_see_ Ironstone). + + Eisleben. + Heap roasting, =279=; 274 + + _Electrum_, 458; 2; 35 + + Elements, Peripatetic Theory of, 44 + + Emery, 115 + + Erbisdorff. + Tin strakes, =304= + + _Excoctores_ (_see_ Smelters). + + Exhalations. + From veins, =38=; =44= + + Exhausted Liquation Cakes (_see_ Liquation Cakes, Exhausted). + + + Fans, Ventilation, =203-207= + + Fathom, 616; =77=; 78 + + _Federwis_, (_see also_ Asbestos), 114; 274 + + Feldspar, 114 + + _Ferrugo_ (_see_ Iron-rust). + + _Ferrum purum_ (_see_ Native Iron). + + _Fibrae_ (_see_ Stringers). + + Fineness, Scales of, 253; 617 + + Fire-setting, =118-120=; 118-119 + + Firstum Mines (_see_ Fürst). + + Fissure Vein (_see_ _Vena profunda_). + + Flame. + Determination of metal by, =235= + Determination of required flux by, =235= + + Flint, as a Flux, 380 + + Float, from Veins, =37= + + Flookan, 101 + + Flue-dust, =394-396= + + _Fluores_ (_see_ Fluorspar). + + Fluorspar, 115; 380; 381 + Indication of ore, =116= + + _Flüsse_ (_see_ Fluorspar). + + Fluxes (_see also_ Argol, Saltpetre, Limestone, Stones which easily + melt, _etc._), =232-239=; 232; 237; 380; 221 + Basic, 237 + De-sulphurizing, =236=; 237 + For smelting, =379=; =380=; =386=; =390= + Reducing, =236=; 237 + Stock fluxes for assaying, =236= + Sulphurizing, =236=; 237 + + Footwall, =68=; =117= + + Forehearth, =356=; =375-378=; =386=; 355 + For tin furnaces, =411=; =413= + + Foreman (_see_ Mining Foreman). + + Forest-Fires, =36=; 36 + + Forest of Dean, 84 + + Forest of Mendip, 84 + + _Formae_, 101 + + _Fossa latens_ (_see also_ Drifts), 101 + + _Fossa latens transversa_ (_see also_ Crosscuts), 101 + + _Fossores_ (_see_ Miners). + + Founders' Hoards, 355; 402 + + Fractional Meers, =80= + + France. + Mediæval mining law, 84 + + Free Mining Cities, 84 + + Freiberg, =XXXI.= + Age of the mines, =5= + Bergmeister, =95= + Division of shares, =81=; =90=; =91= + First discovery of veins, =35=; 36 + Flooding of mines, =218= + Method of cupellation, =482= + + Fullers' Earth, 115 + + Fumes. + From heated ore, =235= + Poisonous, =215-216= + + _Fundamentum_ (_see also_ Footwall), 101 + + _Fundgrube_ (_see also_ Meer), 77 + + Furnaces, =374-378=; =386=; =388=; 355; 492 + Assaying (_see_ Assay Furnaces). + Bismuth smelting, =433-437= + Burning tin concentrates, =349= + Cementation, =455= + Copper smelting, =401-408= + Cupellation, =467-468=; =482-483= + "Drying" liquated copper, =522-526= + Enriching copper bottoms, =510= + Gold and silver ores, =382-384= + Heating copper cakes, =503= + Iron smelting, =420-421=; 420 + Latin and German terms, 220 + Lead ores, =408-410= + Liquation of silver, =515= + Melting lead cakes, =498= + Nitric acid making, =441= + Parting precious metals with antimony, =452-453= + Quicksilver distillation, =426-432= + Refining copper, =531-533= + Refining silver, =483=; =489= + Refining tin, =418= + Roasting, =276-277= + Smelting liquation slags, =507= + Tin smelting, =411-413=; =419= + + Furnace Accretions, 113; 221; 492 + Removal of, =376= + + Furnace Hoods, =494= + + Fürst. + Mines of, =24=; 24 + + + _Gaarherd_ (_see_ Refining-hearth). + + _Gaarmachen_ (_see_ Copper Refining). + + Gad, 150 + + Galena, 51; 109; 110; 221 + Bismuth distinguished from, 3 + Smelting of, =400-401= + + Gangue Minerals, 48 + + Garlic. + Magnet weakened by, =39= + + Garnets, =334= + + Gases (_see also_ Fumes) + From fire-setting, =120= + + _Gedigen eisen, silber_, etc. (_see_ Native Iron, Silver, etc.). + + _Gel atrament_ (_see_ _Misy_). + + Gems, =115=; 1 + + Geology. + Agricola's views, 595 + + Germans. + English mining influenced by, 283 + Mining men imported into England, 282 + Ore-dressing methods, 281-282 + + _Geschwornen_ (in Saxon mines), 77 + + Geyer, =XXXI=; =42=; VI. + Shafts, 102 + Tin-strakes, =304= + + Gilding, 460 + Removal from objects, =460=; =464= + + Gips (_see_ Gypsum). + + Gittelde. + Smelting of lead ore, =391= + + _Glantz_ (_see_ Galena). + + _Glasertz_ (_see_ Silver Glance). + + _Glasköpfe_ (_see_ Ironstone). + + Glass, =584-592= + Blowing, =592= + Furnaces, =586-590= + From sand, 380 + + Glass-galls, 235; 221 + As a flux, =235=; =238=; =243=; =246= + Use in parting gold from copper, =464= + Use in smelting gold concentrates, =397=; =398= + + _Glette_ (_see_ Litharge). + + _Glimmer_ (_see_ Mica). + + Gnomes. + In mines, =217=; 112; 214; 217 + + Goblins (_see_ Gnomes). + + God's Gift Mine (_see_ Gottsgaab Mine). + + Gold (_see also_ Gold Ores, Parting, Smelting, Stamp-Mill, _etc._). + Alluvial mining, =321-336=; 330 + Alluvial streams, =75= + Amalgamation, 297 + Gold-dust, =396= + Historical notes, 399; 354 + Indications of, =108=; =116= + Lust for, not the fault of the metal, =16= + Minerals, 108 + Minerals associated with, =108-109= + Smelting of ores, =381-382=; =386=; =388=; =390=; =396= + Wickedness caused by, =9-10= + + Gold Concentrates, =396-399=; 398 + + Golden Fleece, =330=; 330 + + Gold Ores, =107-108= + Amalgamation, =295-299=; 297 + Assay by amalgamation, =243-244= + Assay by fire, =242-243= + Flux used in assaying, =235= + Flux used in smelting, =398= + Smelting in blast furnace, =398-400= + Smelting cupriferous ores, =404-407= + Smelting in lead bath, =399= + Smelting pyritiferous ore, =398-401= + Stamp-milling, =321= + + _Goldstein_ (_see_ Touchstone). + + Goslar, =5=; =37=; 37 + Lead smelting, =408= + Native zinc vitriol, 572 + Roasting ores, =274=; 274 + Spalling hard ore, =271= + + Goslarite, 113; 572 + + Gottsgaab Mine, VI; VII; =74=; 74 + + Gounce, 267 + + Grand Canal of China, 129 + + Granulation Methods for Bullion, =444= + + Granulation of Copper, =250= + + Greeks. + Antimony, 428 + Brass making, 410 + Copper smelting, 403 + Iron and steel making, 421 + Metallurgy from Egypt, 402 + Mining law, 83 + Ore dressing, 281 + Quicksilver, 432 + Silver-lead smelting, 391 + Smelting appliances, 355 + + Grey Antimony (_see also_ _Stibium_), 110; 221; 428 + + Griffins, 331 + + Groom of the Chamber. + Right to a meer, =81= + + Groove (_see also_ Shafts), 101 + + Ground Sluices, =336-337= + + Ground Waters, 46-48 + + _Grünspan_ (_see_ Verdigris). + + _Gulden_, 92; 419 + + Gunpowder. + First use for blasting in mines, 119 + Invention of, 562 + + Gypsum, 114 + + + Hade, 101 + + _Haematites_ (_see_ Ironstone). + + _Halinitrum_ (_see_ Saltpetre). + + Halle, Salt Industry, =552= + + Hammers, =151= + With water power, =423= + + Hangingwall, =68=; =117= + + Harz Miners. + Agricola consulted, VII. + Antimony sulphide, 428 + First mining charter, 84 + First stamp-mill, 282 + Pumps, =194= + + Hauling Appliances (_see also_ Whims _and_ Windlasses), =160-168=; 149 + + Heap Roasting, =274-276= + + Hearth-lead (_see also_ _Molybdaena_), =475=; 476; 110; 221 + As a flux, =232= + Use in smelting, =379=; =398=; =400= + + Hearths. + For bismuth smelting, =433-437= + For melting lead, =390=; =498= + + Heavenly Host Mine (_see_ _Himmelisch Höz_ Mine). + + Heavy Spar, 115 + + Hebrews. + Knowledge of antimony, 428 + Silver-lead smelting, 391 + Term for tin, 412 + + Hematite, 111 + + Hemicycle (_Hemicyclium_), =137-138= + + _Heraclion_ (_see_ Lodestone). + + _Herdplei_ (_see_ Hearth-Lead). + + Hiero, King, =247=; 247 + + High Peak (Derbyshire). + Mining law, 84 + Nomenclature in mines, 77 + Saxon customs, connection with, 77; 85 + + _Himmelisch Höz_ mine, =74=; =92=; 75 + + Hoe, =152= + + Holidays of Miners, =99= + + Horn Silver, 109 + + Horns of Deer, =230= + + Hornstone, =116=; 114 + + Hungary. + Cupellation, =483= + + _Hüttenrauch_ (_see_ _Pompholyx_). + + + Iglau, Charter of, 84 + + Incense in Cupellation Furnaces, =472= + + Indications of Ore, =106=; =107=; =116= + + _Ingestores_ (_see_ Shovellers). + + India. + Steel, 423 + Zinc, 409 + + _Intervenium_, =51=; =50= + + Investment in Mines, =26-29= + + Iron, 420; 354; 111 + Cast, 420 + Censure of, =11= + Indications of, =116= + Malleable, 420 + Smelting, =420-426= + Sulphur harmful to, =273= + + Iron Age, 420 + + Iron Filings (_see also_ Iron-Scales), 221 + Use in assaying, =234=; =238=; =246= + + Iron Ore. + Assaying of, =247= + Smelting of, =420-426= + + Iron-rust, =116=; =474=; 1; 111 + + Iron-scales, 221 + Flux, =234= + Use in smelting gold, =398= + Use in smelting silver, =400= + Use in making nitric acid, =440= + Use in parting gold from copper, =464= + + Iron-slag, 221 + As a flux, =234=; =235= + + Ironstone, =390=; 111 + + Italians. + Alluvial mining in Germany, =334= + + Italy. + Mining formerly forbidden, =8= + + + Jade, 114 + + Japan. + Steel, 423 + + Jasper, 111; 2 + + _Jaspis_, 114 + + Jet, 34 + + Jigging Sieve, =310=; 267; 283 + + Joachimsthal, VI. + First stamp-mill, 281 + Mining shares and profits, =91=; =92= + + _Jüdenstein_ (_see_ _Lapis Judaicus_). + + Juices, 1; 47 + Agricola's theory, 46; 52 + From springs and streams, =33= + Stone juice, 46; 49 + Tastes of, =34= + + Juices, Solidified. + Agricola's view of, 1; 49 + Extraction of metals from, =350= + Preparation of, =545= + + Julian Alps. + Stamp-milling in, =319= + + Junctions (_see_ Veins, Intersections of). + + _Jurati_ (_see_ Jurors). + + Jurors, =22=; =92=; =96=; 78 + In English mining custom, 85 + Relations to Bergmeister, =95=; 77 + + Justinian Code. + Mines, 84 + + + _Kalchstein_ (_see_ Limestone). + + _Kammschale_, 127 + + Kaolinite (_see_ Porcelain Clay). + + _Katzensilber_ (_see_ Mica). + + King. + Deputy, =94= + Right to a meer, =81= + + _Kinstock_ (_see_ Liquation Cakes, Exhausted). + + _Kis_ (_see_ Pyrites). + + Knockers (_see_ Gnomes). + + _Kobelt_ (_see_ Cobalt). + + Kölergang Vein, =42= + + Königsberg. + Fire-setting, 119 + + _Kupferglas ertz_ (_see_ Copper Glance). + + _Kupferschiefer_ (_see_ Copper Schists). + + Kuttenberg. + Depths of shafts, 102 + + + Labour Condition in Mining Title, =92=; 83-85 + + Lacedaemonians (_see_ Spartans). + + _Lachter_ (_see_ Fathom). + + Ladderways in Shafts, =124=; =212= + + Ladle for Bullion, =382= + + _Lapis aerarius_ (_see_ Copper Ore). + + _Lapis alabandicus_, 380 + + _Lapis Judaicus_, =115=; 115 + + _Lapis specularis_ (_see_ Gypsum). + + Laths (Lagging), 101 + + La Tolfa. + Alum manufacture, 565 + Discovery of, 570 + + Laurion (Laurium), Mt. (_see_ Mt. Laurion, Mines of). + + Lautental, Liquation at, 491 + + Law (_see_ Mining Law). + + Law-suits over Shares in Mines, =94= + + Lead, 354; 390; 110 + Censure of, =11= + Cupellation, =464-483= + Melting prior to liquation, =500= + In liquation cakes, =505-506=; 505; 506 + Refining silver, =483-490= + Smelting of ores, =388-392=; =400= + Use in assaying, =232=; =239=; =242=; =244=; =249=; =251= + Washing in sluices, =347= + + Lead-ash, =237=; 237; 221 + As a flux, =234= + Use in parting gold from copper, =463= + + Lead Bath, =381= + + Lead-glass, 236 + + Lead Granules, =239=; =463=; 221 + + Leading (in liquation), =304=; =507=; =513=; 491; 492; 504 + Components of the charge, =505-509= + + Lead Ochre, 232; 110; 221 + + Lead Ore. + Assay methods, =245-246= + Roasting, =275= + Smelting in blast furnace, =390=; =408= + + Lease, in Australian Title, 77 + + Leaves, Preparation of Bullion into, =444= + + Leberthal, 24 + + Lees of _aqua_ which separates Gold from Silver, 234; 443; 221 + As a flux, =234=; =238= + + Lees of Vinegar (_see also_ Argol), 221 + As a flux, =234=; =236=; =243=; 234 + + Lees of Wine (_see_ Argol). + + Lemnos, Island of, =31= + + Lemnian Earth, 31 + + Leprosy of House Walls (_see_ Saltpetre). + + Level (_see also_ Drift), 101 + + Level, Plummet (_see_ Plummet Level). + + Limestone, 114; 221 + As a flux, =236=; =390= + + Limonite, 111 + + Limp, 267 + + Linares. + Hannibal's mines near, 42 + + Lipari Islands. + Alum from, 566 + + Liquated Silver-lead (_see_ _Stannum_ _and_ Silver-lead). + + Liquation, =519-521=; 491; 519 + Ash-coloured copper from, =529= + Buildings for, 491 + Furnace, =515-518=; 492 + Historical note on, 494 + Losses, 491; 539 + Nomenclature, 492 + + Liquation Cakes, =505-509=; 492; 505; 506 + Enrichment of the lead, =512=; 512 + Extraction of silver from, 512 + From bye-products of liquation, =539-540= + From copper bottoms, =512=; 512 + Proportion of lead in rich silver copper, =509= + + Liquation Cakes, Exhausted, =521-526=; =406=; 492; 520 + + Liquation Slags, 509; 492; 541 + Furnaces for, =507= + Treatment of, =541= + + Liquation Thorns, =522=; =539=; 492; 539; 540 + From cupellation, =543=; 543 + From "drying" copper residues, =529= + + Litharge (_see also_ Cupellation), =475=; =232-238=; 466; 476; 110; 222 + Use in reducing silver nitrate, =447= + Use in smelting, =379=; =398=; =400= + + _Lithargyrum_ (_see_ Litharge). + + Lodestone, =115=; 111; 115; 2 + Compass, 57 + + _Los Pozos de Anibal_, 42 + + _Lotores_ (_see_ Washers). + + Lusitania. + Gold alluvial, =347= + Sluices for gold washing, =325= + Tin smelting, =419= + + Lute, 1 + Preparation of for furnace linings, =375-376= + + Lydia. + Mining law, 83 + The King's mines, 27 + + Lye, =558=; 221; 233 + Use in making fluxes, =236= + Use in parting, =463= + + + _Magister Metallicorum_ (_see_ Bergmeister). + + _Magister Monetariorum_ (_see_ Master of the Mint). + + _Magnes_ (_see also_ Lodestone _and_ Manganese), =585=; 111; 115; 585 + + Magnet, =247= + Garlic, =39= + + _Magnetis_ (_see_ Mica). + + Magnetite, 111 + + Malachite, 109; 221 + + Maladies of Miners, =214-217= + + Maltha, 581 + + Manager (_see_ Mine Manager). + + Manganese, 586; 354 + + Mannsfeld Copper Slates, =126-127=; =279=; 127; 273 + + Map-making, 129 + + Marble, =115=; 2; 114 + + Marcasite, 111; 112; 409 + + _Marga_ (_see_ Marl). + + Marienberg, =XXXI=; VI. + + Marl, 114 + + Marmelstein (_see_ Marble). + + _Marmor_ (_see_ Marble). + + _Marmor alabastrites_ (_see_ Alabaster). + + _Marmor glarea_, 114 + + Massicot (_see also_ Lead Ochre), 110; 221; 232 + + Master of the Horse, =81= + + Master of the Mint, =95=; 78 + + Matte (_see_ Cakes of Melted Pyrites). + + Matte Smelting, =404-407= + + Measure (unit of mining area), =78=; 78 + + Measures, 616-617; 78; 550 + + Medicine. + Knowledge necessary for miners, =3= + + _Medulla saxorum_ (_see_ Porcelain Clay). + + Meer, =77-89= + Boundary stones, =87= + On _vena cumulata_, =87= + On _vena dilatata_, =86= + + Meissen. + Dumps from mines, =312= + + _Melanteria_, =117=; 112; 573 + Indication of copper, =116= + + Melanterite, 111 + + Melos, Island of, 566 + + _Menning_ (_see_ Red-lead). + + _Mergel_ (_see_ Marl). + + Metals, 2; 44; 51 + Advantages and uses, =19=; =20= + Necessity to man, =XXV=; =12-13= + Not responsible for evil passions, =15= + + _Metreta_, 153 + + Mexico. + Patio process, 297 + + Mica, 114 + + Middle Ages, Mining Law of, 84 + + Mills for Grinding Ore, =294-299=; 280 + + Mimes (_see also_ Gnomes), 217 + + Mine Captain, =26=; 77 + + Mine Manager, =97=; =98=; 77; 78 + + Mineral Kingdom, Agricola's Divisions of, 1 + + Minerals, 594; 108; 48; 51 + Compound, 2; 51 + Mixed, 2; 51 + + Miners, =1-4=; =25=; 78 + Duties and punishments, =100=; =22= + Law (_see_ Mining Law). + Litigation among, =21= + Slaves as, =23= + + Mines. + Abandonment of, =217= + Conditions desirable, =30-33= + Investments in, =26-29= + Management of, =25=; =26= + Names of, =42= + + Mines Royal, Company of, 283 + + Mining (_see also_ Sett, Lease, Claim, Meer, _etc._). + Criticisms of, =4-12= + Harmless and honourable, =14=; =20=; =23= + Methods of breaking ore, =117-118= + Stoping, =125= + + Mining Clerk, =93=; =95=; =96=; 78 + + Mining Companies (_see_ Companies, Mining). + + Mining Foreman, =98-99=; 78 + Frauds by, =21-22= + + Mining Law, 82-86 + Boundary stones, =87= + Drainage requirements, =92-93= + England, 84-86 + Europe, 84 + Forfeiture of title, =92-93= + France, 84 + Greek and Roman, 83 + Middle Ages, 84-85 + Right of Overlord, Landowner, State and Miner, 82 + Tunnels, =88-89= + + Mining Prefect, =26=; =94=; 78 + + Mining Rights (_see_ Mining Law _and_ Meer). + + Mining Terms, Old English, 77; 101 + + Mining Tools, =149-153= + Buckets for ore, =153-154= + Buckets for water, =157= + Trucks, =156= + Wheelbarrows, =155= + + _Minium_, 111 + Quicksilver from, 433 + Red-lead, 232 + + _Minium secundarium_ (_see_ Red-lead). + + Mispickel (_Mistpuckel_), 111 + + _Misy_ (the mineral), 573; 111; 403 + An indication of copper, =116= + Use in parting gold and silver, 459 + + _Mitlere und obere offenbrüche_ (_see_ Furnace Accretions). + + _Modius_, 617; 405 + + Moglitz. + Tin working, =318= + + Moil, 150 + + _Molybdaena_, 110; 221; 476; 400; 408 + Term for lead carbonates, 400; 408 + + Molybdenite, 477 + + _Monetarius_ (_see_ Coiners). + + Money, Assaying of, =251-252= + + Morano Glass Factories, =592= + + Moravia. + Cupellation, =483= + Stamp-milling, =321= + Washing gold ore, =324= + + Mordants, 569 + + Mortar-box, =279-280=; =312=; =319=; 267 + + Mountains. + Formation of, =595= + + Mt. Bermius. + Gold Mines of, =26=; 27 + + Mt. Laurion, Mines of, =27=; 27-29; 391 + Crushing and concentration of ores, 281 + Cupellation, 465 + Mining law, 83 + Smelting appliances, 355 + Xenophon on, =6= + + Mt. Sinai. + Ancient copper smelting, 355; 402 + + Muffle Furnaces, =224-228=; =239= + + Muffles, =227=; =239=; 222 + Refining silver, =489-490= + + Mühlberg, Battle of, X. + + _Murrhina_ (_see_ Chalcedony). + + Muskets, =11= + + Mycenae. + Copper, 402 + Silver-lead smelting, 391 + + + Names of Mines, =42= + + Naphtha, 581 + + Native Copper, 109 + + Native Iron, 111 + + Native Minerals, =107= + + Native Silver, =269=; 109 + + Natron (_see_ _Nitrum_). + + Neolithic Furnaces, 355 + + Neusohl, Method of Screening Ore, =290= + + Newbottle Abbey, 35 + + Nitocris, Bridge of, 391 + + Nitric Acid (_see also_ _Aqua valens_), =439-443=; 460; 439; 354 + Assay parting gold and silver, =248= + Testing silver regulus with, =449= + Use in cleaning gold dust, =396= + + _Nitrum_ (_see also_ Soda), 558; 110 + + Nomenclature, I; 267 + Mining law, 77; 78 + Mining officials, 77; 78 + + _Norici_, 388 + Conveyance of ore, =169= + + Normans. + Mining Law in England, 85 + + Notary, =94=; 78 + + Nubia. + Early gold-mining, 399 + + Nuremberg, Scale of Weights, =263= + + + _Obolus_, 25 + + _Ochra nativa_, 111 + + Ochre Yellow, 111 + + _Offenbrüche_ (_see_ Furnace Accretions). + + Olynthus. + Betrayal to Philip of Macedon, =9= + + Operculum, =441=; 222 + + Orbis, =141=; 137 + + Ore (_see various metals_, Assaying, Mining, _etc._). + + Ore Channels (_see_ Canales). + + Ore Deposits, Theory of, XIII; 43-53 + + Ore Dressing, =267-351= + Burning, =273= + Hand spalling, =271-272= + Sorting, =268-271= + + _Orguia_, =78=; 78; 617 + + _Orichalcum_ (_see_ _Aurichalcum_). + + Orpiment, 111; 1; 222 + Colour of fumes, =235= + Harmful to metals, =273= + Indication of gold, etc., =116= + Roasted from ore, =273= + Use in assaying, =237= + + Outcrops, 68; 43 + + Ox-blood in Salt Making, =552= + + + Pactolus, Gold Sands of, 27 + + Park's Process, 465 + + Parting Gold from Copper, =462-464= + + Parting Gold from Silver, =443-460=; 458-463 + Antimony sulphide, =451-452=; 451-452; 461 + Cementation, =453-457=; =453-454=; =458= + Chlorine gas, 458; 462 + Electrolysis, 458; 462 + Nitric acid, =443-447=; 443; 447; 460 + Nitric acid (in assaying), =247-249= + Sulphur and copper, =448-451=; 448; 461 + Sulphuric acid, 458; 462 + + Partitions, 493 + + Passau, Peace of, IX. + + _Passus_, 616; 78 + + Patio Process, 297-298 + + Pattinson's Process, 465 + + Peak, The (_see_ High Peak). + + _Pentremites_, 115 + + Pergamum. + Brazen ox of, =11= + Mines near, =26=; 27 + + Peripatetics, XII. + Theory of ore deposits, =47=; 44 + View of wealth, =18= + + Persians. + Ancient mining law, 83 + + _Pes_, 616; 78 + + Pestles, =231=; =483= + + Petroleum, 581-582 + + Phalaris, Brazen Bull of, =11= + + Philosophy. + Knowledge necessary for miners, =3= + + Phoenicians. + Copper and bronze, 402 + In Thasos, 24 + Tin, 411-412 + + Picks, =152-153= + + _Pickschiefer_ (_see_ Ash-coloured Copper). + + Placer Mining, =321-348= + + _Pleigeel_ (_see_ Lead Ochre). + + _Pleiweis_ (_see_ White-lead). + + Pleygang Vein, =42= + + _Plumbago_, 110 + + _Plumbum candidum_, 110; 3; 473 + + _Plumbum cinereum_, 111; 3 + + _Plumbum nigrum lutei coloris_, 110; 3 + + Plummet Level. + Standing, =143=; 137 + Suspended, =145=; =146=; 137 + + Pockets in Alluvial Sluices, =322-330= + + Poisonous Fumes (_see_ Fumes). + + Poland. + Cupellation, =483= + Lead ore washing, =347= + Lead smelting, =392= + + _Poletae_, Tablets of the, 83 + + Poling Copper, =531-538=; 535-536 + + Pompeiopolis. + Arsenic mine at, 111 + + _Pompholyx_, 394; 113-114; 403 + From copper refinings, =538= + From cupellation, =476= + From dust-chambers, =394= + From roasting ore, =278= + Poisonous, =214=; 215 + Used for brass making, 410 + + Porcelain Clay, 115 + + Potash, =558-559=; 558; 233; 220 + In _Sal artificiosus_, =463= + + Pottery, Egyptian, 391 + + Potosi, 298 + + Pozos de Anibal, Los, 42 + + _Pous_, 617; 78 + + _Praefectus cuniculi_, 78 + + _Praefectus fodinae_ (_see_ Mine Manager). + + _Praefectus metallorum_ (_see_ Mining Prefect). + + _Praeses cuniculi_, 78 + + _Praeses fodinae_ (_see_ Mining Foreman). + + Precious and Base Metals, 439 + + Primgap, 80 + + _Procurator metallorum_, 83 + + Prospecting, =35= + + Proustite, 108 + + Pumps, =171-200=; 149 + Chain, =171-175= + Rag and chain, =188-200= + Suction, =175-188= + + _Purgator argenti_ (_see_ Silver Refiner). + + Purser, 77 + + Puteoli, =501= + + Pyrargyrite, 108 + + _Pyriten argentum_, 408 + + Pyrites (_see also_ Cakes of Melted Pyrites), 51; 111; 112; 1 + As a flux, =234= + Assay for gold, =243= + In tin concentrates, =348= + Latin and German terms, 222 + Roasting, =273-274= + Roasting cakes of, =349-351= + Smelting for gold and silver, =399=; =401= + Used in making vitriol, 578 + + _Pyrites aerosus_ (_see_ Copper Pyrites). + + _Pyrites aurei coloris_ (_see_ Copper Pyrites). + + + Quartz (_see also_ Stones which easily melt), 114 + As a flux, 380 + An indication of ore, =116= + Material of glass, 380 + Silver ore, =113= + Smelting of, =401= + + _Quarzum_ (_see_ Quartz). + + Quertze, 380 + + Quicksilver, 432; 2; 354; 110 + Amalgamation of gilt objects, =461= + Amalgamation of gold dust, =396= + Amalgamation of gold ores, =297=; 297 + Assaying methods, =247= + Ore, 426-432 + Use in assaying gold ore, =243= + + + Rag and Chain Pumps, =188-200= + + Rake Veins, 101 + + Rammelsberg. + Collapse of mines, =216= + Discovery, 37 + Early vitriol making, 572 + + _Rauchstein_, 127 + + Realgar, 1; 111; 222 + Colour of fumes, =235= + Harmful to metals, =273= + Indication of ore, =116= + Roasted from ore, =273= + + _Rederstein_ (_see_ _Trochitis_). + + Red-lead, 232; 110; 222 + Use in parting gold from copper, =463= + Use in parting gold from silver, =459= + + Refined Salt, =454=; =463=; 233 + + Refinery for Silver and Copper, =491-498= + + Refining Gold from Copper, =462-464= + + Refining Gold from Silver, =443-458= + + Refining-hearth, 492 + + Refining Silver, =483-490=; 465; 484 + + Refining Silver from Lead, =464= + + Reformation, The, V; VIII. + + Re-opening of Old Mines, =217= + + Revival of Learning. + Agricola's position in, XIII. + + Reward Lease, in Australian Law, 77 + + Rhaetia, 388 + + Rhaetian Alps. + Stamp milling in, =319= + + Ring-fire, =448= + + Rio Tinto Mines. + Roman methods of smelting, 405 + Roman water-wheels, 149 + + Risks of Mining, =28-29= + + Rither (a horse), 101 + + Roasted Copper, =233=; 233; 222 + + Roasting, =273-279=; 267 + Heap roasting, =274-275= + In furnaces, =276= + Mattes, =349-351= + Prior to assaying, =231= + + Rocks, =119=; 2 + + Rock-salt, =548=; 222 + Use in cementation, =454= + + Roman Alum, 565 + + Romans. + Amalgamation, 297 + Antimony, 428 + Brass making, 410 + Companies, 90 + Copper smelting, 404-405 + Mining law, 83 + Minium Company, 232 + Quicksilver, 433 + Roasting, 267 + Silver-lead smelting, 392 + Washing of ore, 281 + + Rosette Copper, =538=; 535 + + _Rosgeel_ (_see_ Realgar). + + Ruby Copper, 109; 402 + + Ruby Silver, 51; 108 + Assaying of, =244= + Cupellation, =473= + + _Rudis_ Ores, 108 + + Rust (_see_ Iron-rust). + + + Sabines, =9= + + _Saigerdörner_ (_see_ Liquation Thorns). + + _Saigerwerk_ (_see_ _Stannum_). + + _Salamander har_ (_see_ Asbestos). + + Salamis, Battle of, 27 + + Sal-ammoniac, =560=; 560; 222 + In cements for parting gold and silver, =454-457= + In making _aqua valens_, =441= + Uses in cupellation, =474= + Uses in making _aqua regia_, 460 + Uses in parting gold from copper, =463= + + _Sal artificiosus_, =236=; =463=; 236 + In assaying, =242= + As a flux, =234= + + Salt, =545=; =556=; 546; 233; 222 + As a flux, =234-238= + Pans, =545=; =546= + Solidified juice, 1 + Use in cementation, =454=; 454 + Use in parting gold from copper, =463=; =464= + Use in smelting ores, =396=; =400= + Wells, =546-547= + + Salt made from Ashes of Musk Ivy, 560; 233 + + _Sal torrefactus_, =242=; 222; 233 + + _Sal tostus_, =233=; 233; 222 + + Saltpetre, =561-564=; 561; 562; 222 + As a flux, =233=; =236-238=; =245=; =247= + In smelting gold concentrates, =398= + Uses in cementation, =454=; 454 + Uses in making nitric acid, =439=; =440=; =447=; =454= + Uses in melting silver nitrate, =447= + + Sampling Copper Bullion, =249= + + Sand, =117= + + _Sandaraca_ (_see_ Realgar). + + Sandiver (_see_ Glass-galls). + + _Sarda_ (_see_ Carnelian). + + Saxony. + High Peak customs from, 77; 85 + Political state in Agricola's time, VIII; IX. + Reformation, IX. + + _Saxum calcis_ (_see_ Limestone). + + Scales of Fineness, 253; 617 + + Scapte-Hyle, Mines of, 23 + + Schemnitz. + Age of mines, =5= + Gunpowder for blasting, 119 + Pumps, =194= + + Schist, 222 + + _Schistos_ (_see_ Ironstone). + + Schlackenwald. + Ore washing, =304= + + Schmalkalden League, IX. + + Schmalkalden War, IX; X. + + Schneeberg, =XXXI=; VI. + Cobalt, =435= + Depth of shafts, 102 + Ore stamping, 281 + Shares, =91= + St. George mine, =91=; 74; 75 + + _Schwartz-atrament_ (_see_ _Melanteria_ _and_ _Sory_). + + Scorification Assay, =239= + + Scorifier, =228=; =230=; 222 + Assays in, =238=; =239= + + Screening Ore (_see_ Sifting Ore). + + Screens (_see also_ Screening), 267 + In stamp-mill, =315= + + _Scriba fodinarum_ (_see_ Mining Clerk). + + _Scriba magistri metallicorum_ (_see_ Bergmeister's Clerk). + + _Scriba partium_ (_see_ Share Clerk). + + Scum of Lead from Cupellation, =475= + + Scythians. + Wealth condemned, =9=; =15= + + Seams in the Rocks, =72=; 43; 47 + Indications of ore, =67=; =107= + + Sea-Water, Salt from, =545-546= + + _Sesterce_, 448 + + Sett, 77 + + Settling Pits, =316=; 267 + + Shaft-houses, =102= + + Shafts, =102-107=; =122-124= + Surveys of, =129-135= + _Venae cumulatae_, =128= + + Shakes, 101 + + Share Clerk, =97=; =93=; 78 + + Share in Mines (_see_ Companies, Mining). + + Shears for Cutting Native Silver, =269= + + Shift, =99=; 92 + + Shoes (stamp), =285-286=; 267 + + Shovellers, =153=; =169=; 78 + + _Sideritis_ (_see_ Lodestone). + + _Siegelstein_ (_see_ Lodestone). + + Sieves. + For charcoal, =375= + For crushed ore, =287-293=; =341= + + Sifting Ore, =287-293= + + _Signator publicus_ (_see_ Notary). + + _Silberweis_ (_see_ Mica). + + _Silex_, 114; 118 + + Silver (_see also_ Assaying, Liquation, Parting, Refining, + _etc._), 390; 354; 108 + Amalgamation, 297; 300 + Assaying, =248-251= + Cupellation, =464-483=; =241= + "Drying" copper residues from liquation, 529 + Enrichment in copper bottoms, =510=; 510 + Exhausted liquation cakes, 524 + Indicated by bismuth, etc., =116= + Liquation, =505-507=; 506; 509; 512 + Parting from gold (_see_ Parting Gold and Silver). + Parting from iron, =544=; 544 + Precipitation from solution in copper bowl, =444= + Refining, =483-490=; 465; 484 + Smelting of ores, =381-382=; =386=; =388=; =390=; =400=; =402= + Use in clarification of nitric acid, =443=; 443 + + Silver, Ruby (_see_ Ruby Silver). + + Silver Glance, 108 + Assaying, =244= + Cupellation, =473= + Dressing, =269= + + Silver-Lead Alloy (_see_ _Stannum_, _etc._). + + Silver Ores, =108=; 108 + Assaying, =242-244= + Assaying cupriferous ores, =245= + Fluxes required in assaying, =235= + Smelting cupriferous ores, =404-407= + + Silver-Plating, 460 + + Silver Refiner, =95=; 78 + + Silver Refining (_see_ Refining). + + Silver Veins, =117= + + Singing by Miners, =118= + + Sintering Concentrates, =401= + + Slags (_see also_ Liquation Slags), 222 + From blast furnace, =379=; =381= + From liquation, 491; 492; 523 + + Slaves as Miners, =23=; 83 + In Greek mines, =25=; 25; 28 + + Slough (tunnel), 101 + + Sluices, =319=; =322-348= + + Smallite, 113 + + Smalt, 112 + + _Smega_, 404 + + Smelters, 78 + + Smelting (_see also various metals_), =379-390=; 353-355 + Assaying compared, =220= + Building for, =355-361= + Objects of, =353= + + _Smirgel_ (_see_ Emery). + + _Smiris_ (_see_ Emery). + + Smyrna. + Mines near, 27 + + Snake-Bites, 31 + + Soda (_see also_ _Nitrum_), =558=; =559=; 233; 222 + As a flux, =233=; =234= + Historical notes, 558; 354 + Solidified juice, 1 + + Sole, 101 + + Solidified Juices (_see_ Juices, Solidified). + + _Solifuga_, =216=; 216 + + Sorters, 78 + + Sorting Ore, =268-271= + + _Sory_, 112; 403; 573 + + Sows, =376=; =386=; 376 + + Spain (_see also_ Lusitania). + Ancient silver-lead mines, 149; 392 + Ancient silver mines of Carthage, =27= + Ancient tin mines, 411-412 + + Spalling Ore, =271-272= + + _Spangen_ (_see_ _Trochitis_). + + _Spanschgrün_ (_see_ Verdigris). + + Spartans. + Gold and silver forbidden, =9=; =15= + Interference with Athenian mines, 27 + + Spat (_see_ Heavy Spar). + + Spelter, 409 + + Sphalerite, 113 + + _Spiauter_, 409 + + _Spiesglas_ (_see_ _Stibium_). + + Spines of Fishes for Cupels, =230= + + _Spodos_, =538=; 394; 113; 114 + + _Spuma argenti_ (_see_ Litharge). + + Staffordshire. + First pumping engine, 149 + + Stalagmites, 114 + + Stall Roasting, =350-351= + + Stamp, 267 + For breaking copper cakes, =501-503= + For crushing crucible lining, =373-375= + + Stamping Refined Silver, =489= + + Stamp-mill, =279-287=; 281-282; 267 + Wet ore, =312-314=; =319-321= + + Standing Plummet Level (_see_ Plummet Level). + + Stannaries, 85 + + _Stannum_, 473; 2; 384; 492 + + Steel, =423-426=; 422-423; 354 + + _Steiger_, 77 + + _Steinmarck_ (_see_ Porcelain Clay). + + Stemple (stull), 101 + + Stephanite, 109 + + Sternen Mine, =92=; 75 + + Steward (of High Peak mines), 77 + + St. George Mine (Schneeberg), =91=; 74; 75 + + _Stibium_ (_see also_ Antimony _and_ Antimony Sulphide), 110; 428; 2; 221 + Flux to be added to, =235= + In assaying, =237-239= + In cementation, =458-460= + Indication of silver, =116= + In making nitric acid, =440= + In parting gold and silver, =451-452=; =459= + In parting gold from copper, =464= + In treatment of gold concentrates, =396=; =397= + + Stibnite, 428; 451 + + St. Lorentz Mine, =74=; =92= + + Stockwerke (_see_ _Vena cumulata_). + + Stoics. + Views on wealth, =18= + + _Stomoma_, =423= + + Stone Juice, 46; 49 + + Stones. + Agricola's view of, 2; 46; 49 + Various orders of fusibility, =380= + + "Stones which Easily Melt" (_see also_ Quartz), 380; 222 + As a flux, =233=; =236=; 233 + In making nitric acid, =440= + In smelting, =379=; =380=; =390= + Smelting of, =401= + + Stool (of a drift), 101 + + Stope, =126= + + Stoping, =125= + _Venae cumulatae_, =128= + _Venae dilatatae_, =126=; =127= + + Strake, =303-310=; 267; 282 + Canvas, =307-310=; =314=; =316=; 267 + Egyptians, 280 + Greeks, 281 + Short, =306-307=; 267 + Washing tin concentrates, =341-343= + + Strata, =126= + + Streaming, =316-318= + + Stringers, =70=; 43; 47; 70 + Indication of ore, =106= + Mining method, =128= + + Styria, =388= + + Subterranean Heat, 46; 595 + + Suction Pumps, =175-188= + + Sulphides, 267; 355 + + Sulphur, =578-581=; 579; 222 + Colour of fumes, =235= + Harmful to metals, =273= + In assaying, =235-238= + In parting gold from copper, =463=; 462 + In parting gold from silver, =448-451=; 448; 461 + In smelting gold dust, =396= + Roasted from ores, =273=; =276= + Solidified juice, 1 + + Sulphur "not exposed to the fire," =458=; =463=; 579 + + Surveyor's Field, =137=; =144=; 142 + + Surveying, =128-148=; 129 + Necessary for miners, =4= + Rod, =137-138= + + Suspended Plummet Level (_see_ Plummet Level). + + Swiss Compass, =145=; 137 + + Swiss Surveyors, =145= + + _Symposium_, =91= + + + Tap-hole, =378=; =386= + + Tappets, =282=; =319=; 267 + + Tapping-bar, =381= + + Tarshish, Tin Trade, 412 + + Tartar (Cream of), 220; 234 + + _Tectum_ (Hangingwall), 101 + + _Terra sigillata_ (_see_ Lemnian Earth). + + "Tests", refining silver in, =483-490=; 465; 484 + + _Thaler_, 92 + + Thasos, Mines of, =23=; =95=; 23 + + _Theamedes_, 115 + + Theodosian Code. + Mines, 84 + + Thorns (_see_ Liquation Thorns). + + Thuringia. + Roasting pyrites, =276= + Sluices of gold washing, =327= + + Tigna (Wall plate), 101 + + Timbering. + Of ladderways and shafts, =122=; =123=; =124= + Of stopes, =126= + Of tunnels and drifts, =124-125= + + Tin, 411-413; 354; 110 + Alluvial mining, =336-340= + Assaying ore, =246= + Assaying for silver, =251= + Colour of fumes, =235= + Concentrates, =340-342=; =348-349= + Cornish treatment, 282 + Refining, =418-419= + Smelting, =411-420= + Stamp-milling, =312-317= + Streaming, =316-318= + Washing, =298=; =302=; =304= + + _Tincar_ or _Tincal_ (_see_ Borax). + + Tithe Gatherer, =81=; =95=; =98=; 78 + + Tithe on Metals, =81=; 82 + + _Toden Kopff_, 235 + + _Tofstein_ (_see_ _Tophus_). + + Tolfa, La (_see_ La Tolfa). + + Tools, =149-153= + + _Topfstein_ (_see_ _Tophus_). + + _Tophus_, 233; 114; 222 + As a flux, =233=; =237=; =390= + + Tortures. + With metals, =11= + Without metals, =17= + + Touch-needles, =253-260=; 253 + + Touchstone, =252-253=; 252; 354; 458; 222 + Mineral, 114 + Uses, =243=; =248=; =447= + + Trade-routes. + Salt-deposits influence on, 546 + + Transport of Ore, =168-169= + + Trent, Bishop of. + Charter (1185), 84 + + Triangles in Surveying, =129-137= + + Tripoli, 115 + + _Trochitis_, =115=; 115 + + Trolley, =480=; =500=; =514= + + Troy. + Lead found in, 391 + + Troy Weights, 616; 617; 242 + + Trucks, =156= + + Tunnels, =102=; 101 + Law, =88-93= + Surveys of, =130-141= + Timbering, =124= + + Turin Papyrus, 129; 399 + + Turn (winze), 101 + + _Tuteneque_, 409 + + _Tuttanego_, 409 + + Tutty, 394 + + Twitches of the Vein, 101 + + Twyer, 376 + + Tye, 267 + + Type. + _Stibium_ used for, 2; 429 + + Tyrants. + Inimical to miners, =32= + + Tyrolese. + Smelting, =388=; =404= + + + Ulcers, =214=; 31 + + _Uncia_ (length), =78=; 616; 78 + + _Uncia_ (weight), 616; 242 + + Undercurrents (_see_ Sluices). + + United States. + Apex law, 82 + + + _Vectiarii_ (_see_ Windlass Men). + + Veins, =43=; =64-69=; =106-107=; 47 + Barren, =72=; =107= + Direction of, =54-58= + Drusy, =72=; =73=; =107= + Hardness variable, =117= + Indications, =35-38= + Intersections of, =65=; =66=; =67=; =106=; =107= + + _Vena_. + Use of term, 43; 47 + + _Vena cumulata_, =46=; =49=; =70=; 43; 47 + Mining method, =128= + Mining rights, =87= + + _Vena dilatata_, =41=; =45=; =53=; =60-61=; 43; 47 + Junctions with _vena profunda_, =67=; =68= + Mining method, =126-127= + Mining rights, =83-86= + Washing lead ore from, =347= + + _Vena profunda_, =44=; =51=; =60=; =62=; =63=; =68=; =69=; 43; 47 + Cross veins, =65= + Functions, =65=; =66=; =67=; =68= + Mining rights, =79-83= + + Venetian Glass, 222 + Factories, =592= + In assaying, =238=; =245=; =246= + In cupellation, =474= + + Venice. + Glass-factories, =592= + Parting with nitric acid, 461 + Scale of weights, =263= + + Ventilation, =200-212=; =121= + With bellows, =207-210= + With fans, =203-207= + With linen cloths, =210= + With windsails, =200-203= + + Verdigris, 440; 1; 110; 222 + In cementation, =454=; =457= + Indication of ore, =116= + In making nitric acid, =440= + In parting gold from copper, =464= + + Vermilion. + Adulteration with red-lead, 232 + Poisonous, =215= + + Villacense Lead, =239=; 239 + + Vinegar. + Use in breaking rocks, =119=; 118 + Use in cleansing quicksilver, =426= + Use in roasting matte, =349= + Use in softening ore, =231= + + _Virgula divina_ (_see_ Divining Rod). + + Vitriol, =571=; 572; 403; 222; 1 + In assaying, =237-238= + In cementation, =454=; 454 + Indication of copper, =116= + In making nitric acid, =439-440= + In roasted ores, =350= + In _sal artificiosus_, =463= + Native, 111 + Native blue, 109 + Native white, 113 + Red, 274 + White, 454 + + Volcanic Eruptions, 595 + + + Washers, 78 + + Washing Ore (_see also_ Concentration, Screening Ore, _etc._), =300-310= + + Water-Bags, =157-159=; =198= + + Water-Buckets, =157-158= + + Water-Wheels, =187=; =283=; =286=; =319= + + Water-Tank, under Blast Furnaces, =356-357= + + Wealth, =7-20= + + Wedges, =150= + + Weights, =260-264=; 616-617; 242; 253 + + _Weisser Kis_, 111 + + _Werckschuh_, 617; 78 + + Westphalia. + Smelting lead ore, =391= + Spalling ore, =272= + + Wheelbarrows, =154= + + Whims, =164-167= + + White-Lead, 440; 354; 110; 232 + + White Schist, =234=; =390=; 234; 222 + + Winding Appliances (_see_ Hauling Appliances). + + Windlasses, =160=; =171=; 149 + + Windlass Men, =160=; 78 + + Winds. + Greek and Roman names, =58= + Sailors' names, =59=; =60= + + Winds (winze), 101 + + Windsails, =200-203= + + Winzes, 102 + + Wittenberg, Capitulation of, IX. + + Wizards. + Divining rods, =40= + + Workmen, =98=; =100= + + Woughs, 101 + + + _Zaffre_, 112 + + Zeitz, XI. + + Zinc (_see also_ _Cadmia_ _and_ Cobalt). + Historical notes, 408-410; 354 + Minerals, 112-113 + + Zinck (_see_ Zinc). + + Zinc Oxides, 113; 354 + + Zinc Sulphate (_see_ Vitriol). + + _Zincum_ (_see_ Zinc). + + _Zoll_, 617; 78 + + Zwickau, VI. + + _Zwitter_, 110 + + + + +INDEX TO PERSONS AND AUTHORITIES. + +NOTE.--The numbers in heavy type refer to the Text; those in plain type +to the Footnotes, Appendices, etc. + + + Acosta, Joseph De, 298 + + Aeschylus. + Amber, 35 + + Aesculapius. + Love of gold, =9= + + Africanus (alchemist), =XXVII=; XXVIII + + Agatharchides. + Cupellation, 465 + Egyptian gold mining, 279; 391; 399 + Fire-setting, 118 + + Agathocles. + Money, =21= + + Agathodaemon (alchemist), =XXVII=; XXVIII + + Agricola, Daniel, 606 + + Agricola, Georg (a preacher at Freiberg), 606 + + Agricola, Georgius. + Assaying, 220 + Biography, V-XVI + Founder of Science, XIV + Geologist, XII; 46; 53 + Interest in _Gottsgaab_ mine, VII; 74 + Mineralogist, XII; 108; 594 + Paracelsus compared with, XIV + Real name, V + Works, Appendix A + See also: + _Bermannus._ + _De Animantibus._ + _De Natura eorum_, etc. + _De Natura Fossilium._ + _De Ortu et Causis._ + _De Peste._ + _De Precio Metallorum._ + _De Re Metallica._ + _De Veteribus Metallis._ + Etc. + + Agricola, Rudolph, 606 + + Albert the Brave, Duke of Meissen, VIII + + Albertus Magnus (Albert von Bollstadt), XXX; 609 + Alluvial gold, =76= + Cementation, 460 + Metallic arsenic, 111 + Metals, 44 + Saltpetre, 562 + Zinc, 409 + + Albinus, Petrus, V; 599 + Cuntz von Glück, 24 + + Alpinus, Prosper, 559 + + Alyattes, King of Lydia. + Mines owned by, =26=; 27 + + American Institute of Mining Engineers, 38; 53 + + Anacharsis. + Invention of bellows, 362 + + Anacreon of Teos. + Money despised by, =9=; =15= + + Anaxagoras. + Money despised by, =15= + + Anna, Daughter of Agricola, VII + + Anna, Wife of Agricola, VII + + Antiphanes. + On wealth, =19= + + Apollodorus, 26 + + Apulejus (alchemist), =XXVII=; XXIX + + Archimedes. + King Hiero's crown, =247= + Machines, 149 + + Ardaillon, Edouard. + Mt. Laurion, 28; 281; 391 + + Aristippus. + Gold, =9=; =14= + + Aristodemus. + Money, =8= + + Aristotle, XII; 607 + Amber, 35 + Athenian mines, 27; 83 + Burning springs, 583 + Coal, 34 + Cupellation, 465 + Distillation, 441 + Lodestone, 115 + Nitrum, 558 + Ores of brass, 410 + Quicksilver, 432 + Silver from forest fires, 36 + Theory of ore deposits, 44 + Wealth of, =15= + + Arnold de Villa Nova. (_see_ Villa Nova, Arnold de). + + Athenaeus. + Silver from forest fires, 36 + + Augurellus, Johannes Aurelius (alchemist), =XXVII=; XXX + + Augustinus Pantheus (alchemist), =XXVII= + + Augustus, Elector of Saxony, =IX= + Dedication of _De Re Metallica_, =XXV= + Letter to Agricola, =XV= + + Avicenna, XXX; 608 + + + Bacon, Roger, XXX; 609 + Saltpetre, 460; 562 + + Badoarius, Franciscus, =XXVII= + + Balboa, V. N. de, V + + Ballon, Peter, 559 + + Barba, Alonso, 300; 1 + + Barbarus, Hermolaus, =XXVII= + + Barrett, W. F., 38 + + Becher, J. J., 53 + + Bechius, Philip, XV + + Beckmann, Johann. + _Alumen_, 565 + Amalgamation, 297 + _Nitrum_, 559 + Parting with nitric acid, 461 + Stamp-mills, 281 + _Stannum_, 473 + Tin, 412 + + _Bergbüchlein_ (_see_ _Nützlich Bergbüchlin_). + + _Bergwerks lexicon_, 37; 80; 81 + + Berman, Lorenz, VI; 597 + + _Bermannus_, 596; 599; VI + Arsenical minerals, 111 + Bismuth, 3; 433 + _Cadmia_, 113 + Cobalt, 112 + Fluorspar, 381 + _Molybdaena_, 477 + Schist, 234 + Shafts, 102 + Zinc, 409 + + Berthelot, M. P. E., 429; 609 + + Berthier, 492 + + Bias of Priene. + Wealth, =8=; =14= + + Biringuccio, Vannuccio, 614 + Agricola indebted to, =XXVII= + Amalgamation of silver ores, 297 + Assaying, 220 + Assay ton, 242 + Brass making, 410 + Clarifying nitric acid, 443 + Copper refining, 536 + Copper smelting, 405 + Cupellation, 466 + Liquation, 494 + Manganese, 586 + Parting precious metals, 451; 461; 462 + Roasting, 267 + Steel making, 420 + _Zaffre_, 112 + + Boeckh, August, 28 + + Boerhaave, Hermann, XXIX + + Borlase, W. C. + Bronze celts, 411 + + Borlase, William. + Cornish miners in Germany, 283 + + Born, Ignaz Edler von, 300 + + Boussingault, J. B., 454 + + Boyle, Robert. + Divining rod, 38 + + Brough, Bennett, 129 + + Bruce, J. C., 392 + + Brunswick, Duke Henry of (_see_ Henry, Duke of Brunswick). + + Budaeus, William (Guillaume Bude), 461; 606 + + + Cadmus, 27 + + Calbus (_see also_ _Nützlich Bergbüchlin_), 610; =XXVI=; XXVII + Alluvial gold, =75= + + Caligula. + Gold from _auripigmentum_, 111 + + Callides (alchemist), =XXVII=; XXVIII + + Callimachus. + On wealth, =19= + + Camerarius, =VIII= + + Canides (alchemist), =XXVII=; XXVIII + + Carew, Richard. + Cornish mining law, 85 + Cornish ore-dressing, 282 + + Carlyle, W. A. + Ancient Rio Tinto smelting, 405 + + Carne, Joseph. + Cornish cardinal points, 57 + + Casibrotius, Leonardus, VI + + _Castigationes in Hippocratem et Galenum_, 605 + + Castro, John de, 570 + + Chabas, F. J., 129 + + Chaloner, Thomas, 570 + + Chanes (alchemist), =XXVII=; XXVIII + + Charles V. of Spain, =IX= + Agricola sent on mission to, =X= + + Chevreul, M. E., 38 + + _Chronik der Stadt Freiberg_, 606 + + Cicero. + Divining rod, 38 + Wealth of, =15= + + Cincinnatus L. Quintius, =23= + + Circe. + Magic rod, =40= + + Cleopatra. + As an alchemist, =XXVII=; XXIX + + Collins, A. L. 119 + + Columbus, Christopher, V + + Columella, Moderatus, =XXV=; =XXVI= + + Comerius, =XXVII=; XXIX + + _Commentariorum ... Libri VI._, 604 + + Conrad (Graf Cuntz von Glück), =23=; 24 + + Corduba, Don Juan De, 300 + + Cortes, Hernando, =V= + + Cramer, John, 236 + + Crassus, Marcus. + Love of gold, =9= + + Crates, the Theban. + Money despised by, =15= + + Croesus, King of Lydia. + Mines owned by, =26=; 27 + + Ctesias. + Divining rod, 38 + + Ctesibius. + Machines, 149 + + Curio, Claudius. + Love of gold, =9= + + Curius, Marcus. + Gold of Samnites, =9=; =15= + + + Dana, J. D., 108 + Alum, 566 + Copiapite, 574 + Emery, 115 + Lemnian earth, 31 + Minerals of Agricola, 594 + Zinc vitriol, 572 + + Danae. + Jove and, =10= + + D'Arcet, J. + Parting with sulphuric acid, 462 + + Day, St. John V. + Ancient steel making, 423 + + _De Animantibus Subterraneis_, 597; =VII= + Editions, 600 + Gnomes, =217=; 217 + + _De Bello adversus Turcam_, 605 + + _De Inventione Dialectica_, 606 + + _De Jure et Legibus Metallicis_, =100=; 604 + + _De Medicatis Fontibus_, 605 + + _De Mensuris et Ponderibus_, 597 + Editions, 599 + Weights and measures, =263=; 78 + + _De Metallis et Machinis_, 604 + + Democritus (alchemist), =XXVII=; XXVIII + + Demosthenes. + Mt. Laurion mines, 27; 83 + + _De Natura eorum quae Effluunt ex Terra_, 598; =32= + Dedication, VII + Editions, 600 + + _De Natura Fossilium_, 594; 600; III; XII + Alum, 565 + Amber, 35 + Antimony, 429 + Argol, 234 + Arsenical minerals, 111 + Asbestos, 440 + Bismuth, 110 + Bitumen, 581 + Borax, 560 + Brass making, 410 + _Cadmia_, 113 + _Caldarium_ copper, 511 + Camphor, 238 + _Chrysocolla_, 584 + Coal, 35 + Cobalt, 112 + Copper flowers, 539; 233 + Copper scales, 233 + Crinoid stems, 115 + Emery, 115 + Fluorspar, 380 + Goslar ores, 273 + Goslar smelting, 408 + Iron ores, 111 + Iron smelting, 420 + Jet, 34 + _Lapis judaicus_, 115 + Lead minerals, 110 + Mannsfeld ores, 273 + _Melanteria_, 573 + Mineral Kingdom, 1 + _Misy_, 573 + _Molybdaena_, 476 + Native metals, 108 + Petroleum, 581 + _Pompholyx_, 114; 278 + Pyrites, 112 + Quicksilver, 110 + _Rudis_ minerals, 108 + Sal-ammoniac, 560 + Silver glance, 109 + _Sory_, 573 + _Spodos_, 114 + _Stannum_, 473 + Stones which easily melt, 380 + Sulphur, 578 + _Tophus_, 233 + Touchstone, 253 + White schist, 234 + Zinc, 409 + + _De Ortu et Causis Subterraneorum_, 594; 600; III; VII; XII; XIII + Earths, 48 + Gangue minerals, 48 + Gold in alluvial, =76= + Ground waters, 48 + Juices, 52 + Metals, 51 + Solidified juices, 49 + Stones, 49 + Touchstone, 253 + Veins, 47 + + _De Ortu Metallorum Defensio ad J. Scheckium_, 604 + + _De Peste_, 605; VIII + + _De Precio Metallorum et Monetis_, 597; 600 + Mention by Agricola, =252=; =263= + + _De Putredine solidas partes_, etc., 605 + + _De Re Metallica_, I; XIII; XIV-XVI + Editions, 600; XIV + Title page, =XIX= + + De Soto, Fernandes, V + + _De Terrae Motu_, 604 + + _De Varia temperie sive Constitutione Aeris_, 604 + + _De Veteribus et Novis Metallis_, 597; 600; VII; =XXVI=; 5 + Agricola's training, VI + Conrad, 24 + Discovery of mines, =36=; 5; 37 + _Gottsgaab_ mine, 74 + + Devoz (de Voz), Cornelius, 570; 283 + + Diodorus Siculus, 607 + Alum, 566 + Bitumen, 582 + Cupellation, 465 + Drainage of Spanish mines, 149 + Egyptian gold mining, 279 + Fire-setting, 118 + Lead, 391 + Silver from forest fires, =36= + Tin, 412 + + Diogenes Laertius, 7; 9; 10 + + Dioscorides, 607; 608 + Alum, 566 + Antimony, 428 + Argol, 234 + Arsenic minerals, 111 + Asbestos, 440 + Bitumen, 584 + Brass making, 410 + Burned lead, 237 + _Cadmia_, 112 + _Chalcitis_, 573 + Copper flowers, 233; 538 + Copper smelting, 403 + Cupellation, 465 + Distillation apparatus, 355 + Dust-chambers, 355; 394 + Emery, 115 + Lead, 392 + Lead minerals, 477 + Lemnian earth, 31 + Litharge, 465 + Lodestone, 115 + _Melanteria_, 573 + _Misy_, 573 + Naphtha, 584 + _Pompholyx_, 394; 410 + Quicksilver, 297; 432 + Red-lead, 232 + Sal-ammoniac, 560 + _Sory_, 573 + _Spodos_, 394 + Verdigris, 440 + Vitriol, 572 + White-lead, 440 + + Diphilos, 27; 83 + + Diphilus (poet). + Gold, =10= + + _Dominatores Saxonici_, 606 + + Draud, G., 599 + + Dudae. + Alum trade, 569 + + + Elizabeth, Queen of England. + Charters to alum makers, 283; 570 + Dedication of Italian _De Re Metallica_ to, XV + Importation of German miners, 283; 570 + + Eloy, N. F. J., 599 + + Entzelt (Enzelius, Encelio), 615 + + Erasmus, VI; VIII; XIV + + Ercker, Lazarus. + Amalgamation, 300 + Liquation, 491; 505 + Nitric acid preparation, 443 + Parting gold and silver, 444; 451 + + Eriphyle. + Love of gold, =9= + + Ernest, Elector of Saxony, VIII + + Euripides. + Amber mentioned by, 35 + Plutus, =8=; =7= + + Ezekiel, Prophet. + Antimony, 428 + Cupellation, 465 + Tin, 412 + + + Fabricius, George. + Agricola's death, X + Friendship with Agricola, VIII + Laudatory poem on Agricola, =XXI= + Letters, IX; X; XIV; XV + Posthumous editor of Agricola, 603; 606 + + Fairclough, H. R., III + + Farinator, Mathias, XXVI + + Ferdinand, King of Austria. + Agricola sent on mission to, X + Badoarius sent on mission to, =XXVII= + + Ferguson, John. + Editions of _De Re Metallica_, XVI; 599 + + Feyrabendt, Sigmundi, XV + + Figuier, L., 38 + + Flach, Jacques. + Aljustrel tablet, 83 + + Florio, Michelangelo, XV + + Förster, Johannes, VI + + Francis, Col. Grant, 267; 283 + + Francis I., King of France, IX + + Frederick, Elector of Saxony, VIII; IX + + Froben, Publisher of _De Re Metallica_, XIV; XV + + Frontinus, Sextus Julius, 87 + + + Galen. + Agricola's revision of, 605; VI + Lemnian earth, 31 + Mention by Agricola, 2 + + _Galerazeya sive Revelator Secretorum_, etc., 606 + + Gama, Vasco da, V + + Ganse (Gaunse), Joachim, 267; 283 + + Gatterer, C. W., 599 + + Geber, =XXVII=; XXX; 609 + Alum, =569= + Assaying, 219 + Cementation, 459 + Cupels, 466 + Nitric acid, 460 + Origin of metals, 44 + Precipitation of silver nitrate, 443 + + _Genesis, Book of_, XII; 43 + + George, Duke of Saxony, IX; =310=; 310 + + Gesner, Conrad, 52 + + Gibbon, Edward, 119 + + Glauber, J. R., 410 + + Glück, Cuntz von (_see_ Conrad). + + Gmelin, J. F., 84 + + Göcher, C. G., 599 + + Godolphin, Sir Francis, 282 + + Gowland, William. + Ancient bronze, 410; 411; 421 + Early smelting, 402 + + Graecus, Marcus. + Saltpetre, 562 + + Grommestetter, Paul, 281 + + Grymaldo, Leodigaris, XVI + + Gyges, King of Lydia. + Mines owned by, =26=; 27 + + + Hannibal. + Alps broken by vinegar, 119 + Spanish mines, =42=; 42 + + Hardy, William, 85 + + Heath, Thomas. + On Hero, 129 + + Heliodorus (alchemist), =XXVII=; XXIX + + Henckel, J. F., 53; 112; 410 + + Hendrie, R., 609 + + Hennebert, E., 119 + + Henry, Duke of Brunswick, VII + + Henry, Duke of Meissen, IX + + Hermes (alchemist), =XXVI=; XXVIII + + Hermes (Mercury). + Magic rod, 40 + + Hero. + Underground surveying, 129 + + Herodotus. + Alum, 566 + Bitumen, 582 + Lead, 391 + Mines of Thrace, 23 + _Nitrum_, 558 + + Hertel, Valentine, XIV + + Hiero, King of Syracuse. + Crown, 247 + + Hill, John, 607 + _Auripigmentum_, 111 + + Himilce, wife of Hannibal, 42 + + Hippocrates. + Cupellation, 391; 465 + Lodestone, 115 + + Hiram, King of Tyre. + Mines, 214 + + Hofmann, Dr. R. + Biography of Agricola, V; XI; 599; 603 + + Homer. + Amber, 35 + Divining rod, =40=; 40 + Lead, 391 + Smelting, 402 + Steel, 421 + Sulphur, 579 + Tin, 412 + + Hommel, W. + Early zinc smelting, 409 + + Horace. + Metals, =11= + Wealth, =15=; =17= + + Hordeborch, Johannes, VII + + Houghstetter, Daniel, 283 + + Houghton, Thomas, 85 + + Humphrey, William. + Jigging sieve, 283 + + Hunt, Robert. + Roman lead smelting, 392 + + + Inama-Sternegg, K. T. von, 84 + + _Interpretatio Rerum Metallicarum_ (_see_ _Rerum Metall. Interpretatio_). + + Irene, Daughter of Agricola, VII + + + Jacobi, G. H. + Biography of Agricola, V; 599 + Calbus, XXVII; 610 + + Jagnaux, Raoul. + Ancient zinc, 409 + + Jason. + Golden fleece, 330 + + Jeremiah. + Bellows, 362 + Cupellation, 465 + Lead smelting, 391 + _Nitrum_, 558 + + Jezebel. + Use of antimony, 428 + + Job. + Refining silver, 465 + + Johannes (alchemist), =XXVII=; XXVIII + + John, Elector of Saxony, IX + + John, King of England. + Mining claims, 85 + + John Frederick, Elector of Saxony, IX + + Josephus. + Dead Sea bitumen, 33 + + Jove. + Danae legend, =10= + + Justin, =36= + + Juvenal. + Money, =10= + + + Karsten, K. J. B. + Liquation, 491; 492; 505; 509; 523; 535 + + Kerl, Bruno. + Liquation, 505 + + König, Emanuel, XV + + König, Ludwig, XV + + Kopp, Dr. Hermann, 609; 441 + + + Lampadius, G. A., 462 + + Lasthenes. + Love of gold, =9= + + _Latin Grammar_ (Agricola), 605 + + Leonardi, Camilli, 615 + + Leupold, Jacob, XV; 599 + + _Leviticus_. + Leprosy of walls, 562 + + Lewis, G. R, 84 + + Lewis, 454 + + Libavis, Andrew, 410 + + Lieblein, J. D. C., 129 + + Linnaeus, Charles, 559 + + Livy. + Hannibal's march over the Alps, 119 + + Lohneys, G. E. + Liquation, 491; 505 + Parting with antimony, 451 + Zinc, 409; 410 + + Lucretia, daughter of Agricola, VII + + Lucretius. + Forest fires melting veins, =36= + + Lully, Raymond, =XXVII=; XXX + + Luscinus, Fabricius. + Gold, =9=; =15= + + Luther, Martin, V; VI; VIII; IX + + Lycurgus (Athenian orator). + Prosecution of Diphilos, 27; 83 + + Lycurgus (Spartan legislator). + Wealth prohibited by, =9=; =15= + + + Magellan, F. de, V + + Maltitz, Sigismund, 312 + + Manlove, Edward, 70; 85 + + Marbodaeus, 615 + + Marcellinus, Ammianus. + On Thucydides, 23 + + Marcellus, Nonius, XXXI + + Maria the Jewess, =XXVII=; XXVIII + + Mathesius, Johann. + Cobalt, 214 + Conrad mentioned by, 24 + _De Re Metallica_, XIV + King Hiram's mines, 214 + + Matthew Paris. + Cornish miners in Germany, 283 + + Maurice, Elector of Saxony, =XXV=; VIII; IX; X + + Mawe, J., 70 + + Maximilian, Emperor, =23=; 24 + + Meissen, Dukes of (_see under personal names_: Albert, Henry, _etc._). + + Melanchthon. + Relations with Agricola, VIII; X + + Menander. + Riches, =8= + + Mercklinus, G. A., 599 + + Mercury (_see_ Hermes). + + Merlin (magician), =XXVII=; XXX + + Meurer, Wolfgang. + Letters, IX; X + + Meyer, Ernst von, 248; 569 + + Meyner, Matthias, VII + + Midas, King of Lydia. + Mines owned by, =26=; 27 + + Miller, F. B., 462 + + Minerva. + Magic rod, =40= + + Morris, W. O'C., 119 + + Mosellanus, Petrus, VI + + Moses. + Bitumen, 582 + Lead, 391 + Refining gold, 399 + Rod of Horeb, 38; =40= + + Müller, Max. + Ancient iron, 421 + + + Naevius. + Money, =20= + + Nash, W. G. + Rio Tinto mine, 149 + + Naumachius. + Gold and silver, =8= + + Neckam, Alexander. + Compass, 57 + + Newcomen, Thomas, 149 + + Nicander. + On coal, 34 + + Nicias. + Sosias and slaves of, =25=; 25 + + _Nützlich Bergbüchlin_, 610; =XXVI=; XXVII + Alluvial gold, 75 + Bismuth, 110; 433 + Compass, 57; 129 + Ore-deposits, 44 + Ore-shoots, 43 + Veins, 43; 46; 73 + + + Olympiodorus (alchemist), =XXVII=; XXX + + Oppel, van (_see_ Van Oppel). + + Orus Chrysorichites (alchemist), =XXVII=; XXVIII + + Osthanes (alchemist), =XXVII=; XXIX + + Otho the Great, 6 + + Otho, Prince, 6 + + Ovid. + Mining censured by, =7= + + + Pandulfus Anglus, =XXVI= + + Pantaenetus. + Demosthenes' oration against, 27; 83 + + Pantheus, Augustinus (alchemist), =XXVII= + + Paracelsus, XIV; XXX + Divining rod, 38 + Zinc, 112; 409 + + Paris, Matthew (_see_ Matthew Paris). + + Pebichius (alchemist), =XXVII=; XXVIII + + Pelagius (alchemist), =XXVII= + + Pennent, Thomas, 570 + + Percy, John. + Cementation, 454; 459 + Cupellation, 465 + Liquation, 491 + Parting with antimony, 451; 452 + + Peregrinus, Petrus. + Compass, 57 + + Petasius (alchemist), =XXVII=; XXVIII + + Petrie, W. M. F. + Egyptian iron, 421 + Mt. Sinai copper, 402 + + Pettus, Sir John, XVI; 283 + + Phaenippus. + Demosthenes' oration against, 27; 83 + + Phaeton's sisters, 35 + + Pherecrates, =XXVI= + + Philemon. + Riches, 7 + + Philip of Macedonia, 27 + + Philip, Peter, 282 + + Phillips, J. A., 410 + + Philo. + Lost work on mining, =XXVI= + + Phocion. + Bribe of Alexander, =9=; =15= + + Phocylides. + Gold, =7= + + Photius, 279 + Fire-setting, 118 + + Pindar. + Wealth, =19=; 252 + + Pius II, Pope. + Alum maker, 570 + + Pizarro, F., =V= + + Plateanus, Petrus, XIV + + Plautus. + Gold, =10= + + Pliny (Caius Plinius Secundus), =XXVI=; 608 + Alluvial mining, 331; 333 + Alum, 566 + Amalgamation, 297 + Amber, 35 + Antimony, 428 + Argol, 234 + _Arrhenicum_, 111 + Asbestos, 440 + Bitumen, =33=; 583 + Brass, 410 + British miners, 83 + Cadmia, 112 + Cementation, 459 + Chrysocolla, 560 + Copper flowers and scales, 233; 538 + Copper smelting, 404 + Cupellation, 466 + Drainage of Spanish mines, 149 + _Electrum_, 458 + Fire-setting, 118 + Galena, 476 + Glass, 585; 586 + Hannibal's silver mine, =42=; 42 + Hoisting ore, =157=; 157 + Iron, 11 + Jew-stone, 115 + Lead, 392 + Lemnian earth, 31 + Litharge, =475=; 466; 501 + Lodestone, 115 + Manganese (?), 586 + Metallurgical appliances, 355 + _Misy_, 573 + _Molybdaena_, 466; 476 + Naphtha, 583 + _Nitrum_, 560 + Ore-dressing, 281 + Outcrops, 65 + _Pompholyx_, 396 + Protection from poison, 215 + Quicksilver, 433 + Red-lead, 232 + Roasting, 267 + Sal-ammoniac, 560 + Salt from wood, 558 + Silver-lead smelting, 392 + _Sory_, 573 + _Spodos_, 396 + _Stannum_, 473 + Tin, Spanish, 412 + _Tophus_, 233 + Touchstone, =256=; 253 + Turfs in sluices, =331=; 332 + _Vena_, 43 + Ventilation with wet cloths, =210=; 210 + Verdigris, 440 + Vitriol, 572 + White-lead, 440 + + Plutarch, 25 + + Pluto, =216= + + Polybius. + Ore washing, 281 + Silver-lead smelting, 392; 465 + + Polymnestor, King of Thrace. + Love of gold, =9=; =16= + + Pörtner, Hans, 281 + + Posepny, Franz, 53 + + Posidonius. + Asphalt and naphtha, 584 + Drainage of Spanish mines, 149 + Silver from forest fires, 36 + + Priam, King of Troy. + Gold mines of, =26=; 27 + + _Probierbüchlein_, 612; =XXVI= + Amalgamation, 297 + Antimony, 420 + Assaying, 220 + Assay ton, 242 + Bismuth, 433 + Cementation, 454 + Nitric acid, 439 + Parting, 461; 462; 463 + Precipitation of silver nitrate, 443 + Residues from distillation of nitric acid, 235; 443 + Roasting, 267 + Stock fluxes, 235; 236 + Touchstone, 253 + + Propertius. + Gold, =10= + + Pryce, William. + Adam's fall, 353 + Divining rod, 38 + Juices, 1 + Ore-deposits, 53 + Stamp-mill, 282 + Stringers, 70 + + Psalms. + Silver refining, 465 + + Pulsifer, Wm. H., 391 + + Pygmalion. + Love of gold, =9=; =16= + + + Rachaidibus (alchemist), =XXVII= + + Rameses I. + Map of mines, 129 + + Rameses III. + Leaden objects dating from, 391 + + Raspe, R. E., 300 + + Rawlinson, George, 583 + + Ray, P. Chandra. + Indian zinc, 409 + + Raymond, Rossiter W., 38 + + _Rechter Gebrauch der Alchimey_, 606 + + _Rerum Metallicarum Interpretatio_, 597; VII; 600 + + Reuss, F. A., 599 + + Richter, A. D., V; 599 + + Rodianus (alchemist), =XXVII=; XXVIII + + Rössler, B., 53 + + Royal Geological Society of Cornwall, 84 + + Rühlein von Kalbe (_see_ Calbus). + + + Salmoneus. + Lightning, =11= + + Sandwich, Earl of, trans. Barba's book, 300 + + Sappho. + Wealth, =19= + + Savery, Thomas, 149 + + Saxony, Dukes and Electors of. + (_See under personal names_: Albert, Ernest, _etc._). + + Schliemann, H., 391 + + Schlüter, C. A. + Artificial zinc vitriol, 572 + Copper refining, 535 + Cupellation, 464 + Liquation, 491; 505 + Parting with sulphur, 462 + + Schmid, F. A., V; XV; 599 + + Schnabel and Lewis, 465 + + Scott, Sir Walter. + "Antiquary," 300 + + Seneca. + Wealth of, =15= + + Seneferu. + Copper mines, 402 + + Seti I. + Map of mine, 129 + + Shaw, Peter, XXVIII + + Shoo King. + Copper and lead, 391; 402 + Iron, 421 + + Shutz, Christopher, 283 + + Sigfrido, Joanne. + Ed. Agricola's works, XV + + Socrates. + Riches, =7=; =9=; =14=; =18= + + Solinus, C. Julius. + _Solifuga_, =216=; 216 + + Solomon, King. + Cobalt in mines, 214 + + Solon. + Scarcity of silver under, 27 + + Sosias, the Thracian. + Slaves employed by, =25= + + Stahl, G. E., 53 + + Staunton, Sir George, 409 + + Stephanus (alchemist), =XXVII=; XXX + + Stephenson, George, 149 + + Strabo, 607 + Arsenical minerals, 111 + Asbestos, 440 + Asphalt, 584; 33 + Bellows, 362 + Cementation, 458 + Cupellation, 465 + Drainage of Spanish mines, 149 + Forest fires melting veins, 36 + High stacks, 355 + Lydian mines, 26; 27 + Mt. Laurion, 27 + Silver-lead smelting, 391 + Spanish ore-washing, 281 + Zinc (?), 409 + + Strato. + Lost work on mines, =XXVI=; =XXVII=; XII + + Struve, B. G., 599 + + Synesius (alchemist), =XXVII=; XXIX + + + Tantalus, 27 + + Taphnutia (alchemist), =XXVII=; XXVIII + + Tapping, Thomas, 85 + + Thales of Miletus. + Amber, 35 + + Themistocles. + Athenian mine royalties, 27 + + Theodor, son of Agricola, VII + + Theognis. + Cupellation, 465 + On greed, =18= + Plutus, =8= + Refining gold, 399 + + _Theological Tracts_ (Agricola), 605 + + Theophilus (alchemist), =XXVII=; XXVIII + + Theophilus the Monk, 609 + Brass making, 410 + Calamine, 112 + Cementation, 459 + Copper refining, 536 + Copper smelting, 405 + Cupels, 466 + Divining rod, 38 + Liquation, 494 + Metallurgical appliances, 355 + Parting with sulphur, 461 + Roasting, 267 + + Theophrastus, XII; 607 + Amber, 35 + Arsenical minerals, 111 + Asbestos, 440 + Assaying, 219 + Coal, 34 + Copper minerals, 110 + Copper ore, 403 + Emery, 115 + Lodestone, 115 + Lost works, =XXVI=; 403 + Origin of minerals, 44 + Parting precious metals, 458 + Quicksilver, 297; 432 + Touchstone, 252 + Verdigris, 440 + Vermilion, 232 + White-lead, 391; 440 + + Thompson, Lewis, 462 + + Thoth. + Hermes Trismegistos, XXIX + + Thotmes III. + Lead, 391; 582 + + Thucydides. + Mining prefect, =23=; 23; 95 + + Tibullus. + Wealth condemned by, =16= + + Timocles. + Riches, =8= + + Timocreon of Rhodes. + Plutus, =7= + + Tournefort, Joseph P. De, 566 + + Tubal Cain. + Instructor in metallurgy, 353 + + Tursius, =24= + + Twain, Mark. + Merlin, XXX + + _Typographia Mysnae et Toringiae_, 605 + + + Ulloa, Don Antonio De, 298 + + Ulysses. + Magic rod, =40= + + + Valentine, Basil, XXX; 609 + Antimony, 429 + Divining rod, 38 + Parting with antimony, 461 + Zinc, 409 + + Valerius, son of Agricola, VII + + Van der Linden, J. A., 599 + + Van Oppel, XIII; 52 + + Varro, Marcus, =XXVI= + + Vasco da Gama (_see_ Gama, Vasco da). + + Veiga, Estacia de, 83 + + Velasco, Dom Pedro De, 298 + + Veradianus (alchemist), =XXVII=; XXVIII + + Villa Nova, Arnold De (alchemist), =XXVII=; XXX + + Virgil. + Avarice condemned by, =16= + + Vitruvius, 608 + Amalgamation, 297 + Hiero's Crown, 248 + Pumps, 174; 149 + Red-lead, 232 + Surveying, 129 + Verdigris, 440 + White-lead, 440 + + Vladislaus III., King of Poland, =24= + + Von Oppel (_see_ Van Oppel). + + Voz, Cornelius de (_see_ Devoz, Cornelius). + + + Wallerius, J. G., 234; 273 + + Watt, James, 149 + + Watt, Robert, XXVII + + Wefring, Basilius, XIV + + Weindle, Caspar, 119 + + Weinart, B. G., 599 + + Weller, J. G., V + + Werner, A. G., XIII; 53 + + Wilkinson, J. Gardner. + Bitumen, 582 + Egyptian bellows, 362 + Egyptian gold-washing, 279 + + Williams, John, 53 + + Winkler, K. A., 464 + + Wrotham, William de, 85; 413; 473 + + + Xenophon. + Athenian mines, =28=; =83=; 27; 29 + Fruitfulness of mines, =6= + Mining companies, 90 + Mine slaves, 25; 28 + Quoted by Agricola, =26=; =28= + + + Zimmerman, C. F., 53 + + Zosimus (alchemist), =XXVII=; XXIX + + + + +INDEX TO ILLUSTRATIONS. + + + Alum Making, =571= + + Amalgamation Mill, =299= + + Ampulla, =442=; =446= + + Argonauts, =330= + + Assay Balances (_see_ Balances). + + Assay Crucible, =229= + + Assay Furnaces. + Crucible, =227= + Muffle, =223=; =224= + + + Balances, =265= + + Baling Water, =199= + + Bars, for Furnace Work, =377=; =389= + + Batea, =157= + + Bellows. + For blast furnaces, =359=; =365=; =368=; =370=; =372= + For mine ventilation, =208=; =209=; =211= + For tin furnace, =419= + + Bismuth Smelting, =434=; =435=; =436=; =437= + + Bitumen Making, =582= + + Bitumen Spring, =583= + + Bowls for Alluvial Washing (_see also_ Batea), =336= + + Buckets. + For hoisting ore, =154= + For hoisting water, =158= + + Buddle, =301=; =302=; =314=; =315= + + Building Plan for Refinery, =493= + + Building Plan for Smelter, =361= + + + Chain Pumps, =173=; =174=; =175= + + _Chrysocolla_ Making, =585= + + Circular Fire (_see_ Ring-Fire). + + Clay Washing, =374=; =375= + + Compass, =57=; =59=; =142=; =147= + + Copper Mould for Assaying, =250= + + Copper Refining, =534=; =537= + + Copper Refining Furnace, =532= + + Crane. + For cupellation furnace, =479= + For liquation cakes, =514= + + Crowbars, =152= + + Cupel, =229= + Mould, =231= + + Cupellation Furnace, =468=; =470=; =474= + At Freiberg, =481= + In Poland, =482= + + Cutting Metal, =269= + + + Descent into Mines, =213= + + Dipping-pots, =385=; =387=; =389=; =393=; =415=; =417= + + Distillation (_see_ Nitric Acid _and_ Quicksilver). + + Divining Rod, =40= + + Dogs Packing Ore, =168= + + Drifts, =105= + + Drying Furnace for Liquation, =525=; =527=; =528= + + Dust Chambers, =395=; =417= + + + Fans, Ventilation, =204=; =205=; =206=; =207= + + Fire-Buckets, =377= + + Fire Pump, =377= + + Fire-Setting, =120= + + Forehearth, =357=; =358=; =383=; =385=; =387=; =389=; =417= + + Frames (or Sluices) for Washing Ore or Alluvial, =322-324=; + =326-329=; =331-333= + + Furnaces. + Assaying (_see_ Assay Furnaces). + Blast, =357=; =358=; =373=; =377=; =383=; =385=; =387=; =389=; + =395=; =419=; =424=; =508= + Copper refining, =537= + Cupellation, =468=; =470=; =474=; =481=; =482= + Distilling sulphur, =277= + Enriching copper bottoms, =510= + Glass-making, =587=; =588=; =589=; =591= + Iron smelting, =422=; =424= + Lead smelting (_see also_ Furnaces, blast), =393= + Liquation, =517=; =519=; =525=; =527=; =528= + Nitric acid making, =442= + Nitric acid parting, =446= + Parting precious metals with antimony, =453= + Ditto cementation, =455= + Quicksilver distillation, =427-432= + Refining silver, =485=; =486=; =489= + Roasting, =276= + Steel making, =425= + Tin burning, =349= + Tin smelting, =415= + + + Gad, =150= + + Glass Making, =591= + Furnaces, =587=; =588=; =589= + + Ground Sluicing, =337=; =340=; =343=; =346=; =347= + + + Hammers, =151= + With water-power, =422=; =425= + + Heap Roasting, =275=; =278= + + Hearths. + For bismuth smelting, =436=; =437= + For heating copper cakes, =504= + For melting lead, =393= + For melting lead cakes, =499= + For refining tin, =418= + For roasting, =277= + + Hemicycle, =138= + + Hoe, =152= + + + _Intervenium_, =50= + + Iron Fork for Metal, =387= + + Iron Hook for Assaying, =240= + + Iron Smelting, =422=; =424= + + Iron Tools, =150= + + + Jigging Sieve, =311= + + + Ladders, =213= + + Ladle for Metal, =383= + + Lead Mould for Assaying, =240= + + Liquation Cakes. + Dried, =530= + + Liquation Cakes, Exhausted, =522= + + Liquation Furnaces, =517=; =519=; =525=; =527=; =528= + + Lye Making, =557= + + + Matte Roasting, =350=; =351= + + Meers, Shape of, =79=; =80=; =86=; =87=; =89= + + Mills for Grinding Ore, =294=; =296= + + Muffle Furnaces, =223=; =489= + + Muffles, =228= + + + Nitric Acid Making, =442= + + _Nitrum_ Pits, =559= + + + _Operculum_, =446= + + _Orbis_, =142A= + + + Parting Precious Metals. + With antimony, =453= + By cementation, =455= + With nitric acid, =446= + With sulphur, =449= + + Picks, =152= + + Plummet level. + Standing, =143= + Suspended, =146= + + Pumps. + Chain, =173=; =174=; =175= + Duplex suction, =180=; =185=; =189= + Rag and chain, =191=; =193=; =194=; =195= + Suction, =177=; =178=; =179=; =182=; =183=; =187= + + + Quicksilver Distillation, =427=; =429=; =430=; =431=; =432= + + + Rag and Chain Pumps, =191=; =193=; =194=; =195=; =197= + + Rammers for Fire-Clay, =377=; =383= + + Ring-Fire, for Parting with Sulphur, =449= + + Roasting (_see also_ Heap _and_ Stall Roasting), =278=; =350=; =351=; + =274=; =275=; =276= + + Rosette Copper Making, =537= + + + Salt. + Boiling, =549=; =554=; =555= + Caldron, =551=; =553= + Evaporated on faggots, =556= + Pans, =547= + Wells, =549= + + Saltpetre Making, =563= + + Saxon Lead Furnace, =393= + + Scorifier, =229= + + Seams in the Rocks, =54=; =55=; =56=; =60=; =72= + + Shafts. + Inclined, =104= + Timbering, =123= + Vertical, =103=; =105= + + Shears for Cutting Metal, =269= + + Shield for Muffle Furnace, =241= + + Sifting Ore, =287=; =288=; =289=; =291=; =292=; =293=; =311=; =342= + + Silver. + Cakes, Cleansing of, =476=; =488= + Refining, =484=; =485=; =486=; =489= + + Sleigh for Ore, =168= + + Sluicing Tin, =337=; =338=; =340=; =343= + + Smelter, Plan of Building, =361= + + Soda Making, =561= + + Sorting Ore, =268=; =270= + + Spalling Ore, =270=; =271=; =272= + + Stall Roasting. + Matte, =350=; =351= + Ore, =274=; =276= + + Stamp-mill, =284=; =286=; =287=; =299=; =313=; =320=; =321=; =373= + For breaking copper cakes, =501= + + Stamps, =285= + + Steel Furnace, =425= + + Strake, =302=; =303=; =305=; =306=; =307=; =341=; =342=; =345= + Canvas, =308=; =309=; =317=; =321=; =329= + + Streaming for Tin, =318= + + Stringers. + Associated, =71= + _Fibra dilatata_, =71= + _Fibra incumbens_, =71= + Oblique, =71= + Transverse, =71= + + Surveying. + Rods, =138A= + Shafts and Tunnels, =131= + Triangles, =133=; =134=; =135=; =136=; =137=; =139=; =140= + + Suction Pumps (_see_ Pumps). + + Sulphur Making, =579=; =581= + + + Tap-holes in Furnaces, =389= + + Tapping-bar, =383=; =385= + + "Tests" for Refining Silver, =484=; =485= + + Timbering. + Shafts, =123= + Tunnels, =125= + + Tin. + Bars, =415= + Burning, =349= + Refining, =418= + Smelting, =415=; =419= + + Touch-needles, =255= + + Trays for Washing Alluvial, =334= + + Tread Whim, =163= + + Trough, =159= + For washing alluvial, =335=; =348= + + Trucks, =156= + + Tunnels, =103=; =104=; =105=; =120= + Timbering, =125= + + + Veins. + Barren, =73= + Beginning of, =69= + Cavernous, =73= + Curved, =61= + End of, =69= + Head of, =69= + Horizontal, =61= + Intersections of, =64=; =65=; =66=; =67=; =68= + Solid, =73= + Strike of, =62=; =63= + + _Vena cumulata_, =49=; =70= + + _Vena dilatata_, =45=; =50=; =54=; =60=; =61=; =68=; =69= + + _Vena profunda_, =45=; =50=; =53=; =61=; =62=; =63=; =64=; =68= + + Ventilating with Damp Cloth (_see also_ Bellows, Fans, and + Windsails), =212= + + Vitriol Making, =567=; =574=; =575=; =576=; =577= + + + Wagons, for Hauling Ore, =170= + + Washing Ore (_see_ Sifting Ore). + + Water Tanks, under Furnaces, =358= + + Wedges, =150= + + Weights, for Assay Balances, =262= + + Westphalian Lead Smelting, =393= + + Wheelbarrows, =155= + + Whims. + Horse, =165=; =167= + Tread, =163= + + Windlasses, =161=; =162=; =171= + + Winds, Direction of, =59= + + Windsails for Ventilation, =201=; =202=; =203= + + + + +Transcriber's Notes. + + +This document includes quotes from very early authors. As such, it's no +surprise that there are many spelling and punctuation irregularities. +Also the authors were American, but writing for a British journal. In +addition, whether "ae" and "oe" appear as ligatures or separate +characters seems to be fairly random. Unless there was a clearly +preferred spelling choice, variants were kept as is. All changes are +explicitly documented below. Noted spelling variants that were preserved +include: "aluminum" and "aluminium;" "ampullas" and "ampullae;" +"beechwood" and "beech-wood;" "Blütstein" and "Blüt stein;" "brick dust" +and "brickdust;" "calcspar," "calc spar" and "calc-spar;" derivatives of +"crossbar" and "cross-bar," and similarly for "crosscut," "crosspiece," +etc.; (Hans von) "Dechen" and "Decken;" "desulphurizing" and +"de-sulphurizing;" "dissension" and "dissention" (and their plurals); +"distill" and "distil" (and derivatives); "encrusted" and "incrusted;" +"enquire" and "inquire" (and derivatives); "ensure" and "insure;" +(Lazarus) "Ercker" and "Erckern;" "flavor" and "flavour;" "fluor-spar" +and "fluorspar;" "Flusse" and "Flüsse;" (Rotenburg an der) "Fulda" and +"Fulde;" "Gatter" and "Gatterer" may be the same person; "gold workers," +"goldworkers" and "gold-workers;" "gray" and "grey" (and derivatives); +"grove" and "groove" (English mining term for a shaft); "halitum" and +"halitus;" "Henckel" and "Henkel;" "holm oak" and "holmoak;" +"homogenous" and "homogeneous;" Daniel "Houghsetter," "Houghstetter" and +"Hochstetter;" "Joannes" and "Johannes" (the alchemist); "Johanes" and +"Johannes" (Aurelius Augurellus), a.k.a. "John Aurelio Augurello;" +"Jüdenstein" and "Jüden stein;" "Kinstock" and "Kinstocke;" "Lautental" +and "Lautenthal;" "lawsuit" and "law-suit;" "Leipsic" and "Leipzig;" +"Krat" and "Kratt;" "Mosaic" and "Mosaick;" "mineralogic" and +"mineralogical;" "Nützlich Bergbüchlin," "Nützliche Bergbüchlin," +"Nützlich Bergbüchlein," and "Nützliche Bergbüchlein;" "organisation" +and "organization;" (Thomas) "Pennant" and "Pennent;" "Probier +Büchlein," "Probierbüchlin," "Probierbüchlein," "Probirbüchlein," and +"Probirbüchleyn" (which may be different books in some cases); +derivatives of "pulverise" and "pulverize;" "reagent" and "re-agent" +(and their plurals); derivatives of "recognise" and "recognize;" +"republished" and "re-published;" "salamander har" and "salamanderhar;" +"seashore" and "sea-shore;" "semicircle" and "semi-circle" (and +derivatives); "shovelful" and "shovel-ful;" "spiesglas," "spiesglass," +and "spiesglasz;" "Turkey oak" and "turkey-oak;" "Vannucci," "Vannuccio" +and "Vanuccio" (Biringuccio); "Vectarii" and "Vectiarii;" derivatives of +"volatilise" and "volatilize." + +There appears to be no rule whether punctuation following a quote should +be inside or outside the quotation marks. The text was simply left as +is. + +There appears to be no rule whether Roman numerals have periods after +them or not; even references to the same document may differ. The text +was simply left as is. + +For the text version of the document, replaced the oe-ligature with the +separate characters "oe." Also removed the macron from the "e" in +"pectos." + +Some footnote numbers are skipped. To avoid confusion with references to +the footnotes, none of the footnotes were re-numbered. In particular, +Book I does not have footnote 24; Book VI does not have footnote 9; Book +VIII does not have footnote 9, 10 or 18; Book IX does not have footnote +24; Book XI does not have footnote 3. + +Inserted missing anchor for footnote 1 on page v. + +Changed "Albertham" to "Abertham" on page vii: "the God's Gift mine at +Abertham." + +Changed "honored" to "honoured" on page xi: "most honoured citizens." + +Treated the explanatory text on page xxiv as a footnote (number 1) and +created its anchor on page xxi. + +Changed "license" to "licence" in the note on page xxiv: "only poets +have licence." + +Changed "Bibliotheque" to "Bibliothèque" in the footnote on page xxix: +"the Bibliothèque Nationale." + +Changed "Theosebeia" to "Theosebia" and inserted closing double +quotation mark after "written to Theosebia, etc....'" on page xxx. + +Left "loadstone" on page 2 although it's spelled "lodestone" everywhere +else, because it's in a quote. + +Changed "silver-mines" to "silver mines" on page 5: "the silver mines at +Freiberg." + +Removed the extra comma after "ll." in footnote 20 on page 11: "Odes, +I., 35, ll. 17-20;" and in footnote 21 on page 15: "Satires, II., 3, ll. +99-102." + +Changed "realised" to "realized" on page 25: "his hopes are not +realized." + +Removed extra double quotation mark from before "probable that the work" +on page 28. + +Changed "Hipprocrene" to "Hippocrene" in footnote 19 on page 37: "named +Hippocrene after that horse." + +Changed "Joachimstal" to "Joachimsthal" on page 42. + +Adjusted the formats of the captions to the illustrations on page 45, +55, 56 and 60 to be consistent with other captions. + +Removed extra double quotation mark after "not a metal" in the footnote +from page 51. + +Changed "foot walls and hanging walls" to "footwalls and hangingwalls" +on page 65. + +Changed "hanging-wall" to "hangingwall" in footnote 5 on page 80: "into +the hangingwall." + +Changed "Phaenippis" to "Phaenippus" in the footnote on page 83: "the +other against Phaenippus." + +Inserted double quotation mark after "Droit Francais et Etranger" in the +footnote on page 84. + +Changed "Inama-Strenegg" to "Inama-Sternegg" in the footnote on page 84. + +Changed "Himmelich" to "Himmelisch" on page 92: "Himmelisch Höz." +"Himmelsch hoz" was retained as a variant elsewhere. + +Changed "shovelers" to "shovellers" on page 100: "miners, shovellers, +windlass men." + +The table in the note on page 109 refers to note 7 on p. 573. It would +make more sense to refer to note 8, but was left as is. + +Changed "chrusos" to "chrysos" in the footnote on page 110: "(chrysos, +gold and kolla, solder)." + +The footnote on page 110 contains the reference "(see note xx., p. x)." +Rather than Roman numerals, this appears to be a placeholder to a +reference that was not filled in. Perhaps it should be "(see note 8, p. +560)," but it was left as is. + +Changed "tinstone" to "tin-stone" in the footnote on page 110. + +Changed "De La Pirotechnica" to "De La Pirotechnia" in the footnote on +page 112. + +Changed "Mansfeld" to "Mannsfeld" in the footnote on page 113: +"Mannsfeld copper schists." + +Changed "CoAsA" to "CoAsS" in the footnote on page 113: "Cobaltite +(CoAsS)." + +Changed "Phoenecians" to "Phoenicians" on page 119: "Phoenicians must +have possessed." + +Changed "hanging wall" to "hangingwall" on page 124: "the hangingwall +and the footwall." + +Changed "venæ dilatatæ" (ae-ligature) to "venae dilatatae" on page 127: +"mine venae dilatatae lying down." + +Changed "venæ cumulatæ" (ae-ligature) to "venae cumulatae" on page 128: +"as to venae cumulatae." + +Changed "Watts's" to "Watt's" in footnote 1 on page 149: "Watt's +improvements." + +Changed "locks" to "blocks" on page 151: "blocks, and plates." + +Something is wrong with the sentence on page 153 that ends with the +reference to footnote 3. One metreta is larger than one-sixth of a +congius. Perhaps "metreta" and "congius" should be swapped in this +sentence, but it was left as is. + +Changed "bail" to "bale" on page 153: "iron semi-circular bale." + +Changed "Fosilium" to "Fossilium" twice in the footnote on page 155: "De +Natura Fossilium." + +Changed "decends" to "descends" on page 166: "descends into an +underground chamber," and again on page 190: "the plank descends." + +Changed "Pig-skin" to "Pigskin" in the caption to the illustration on +page 168: "Pigskin sacks." + +Left "vapor" as is in footnote 20 on page 210 although it's spelled +"vapour" everywhere else, because it's in a quote. + +Changed "de hydrated" to "dehydrated" in the footnote on page 221: +"Probably dehydrated alum." + +Changed "Na_{2}Co_{3}" to "Na_{2}CO_{3}" in the footnote on page 222. + +Changed "fore-part" to "forepart" on page 226: "the forepart lies." + +Changed "four-fold" to "fourfold" on page 226: "with fourfold curves." + +Changed "or" to "of" on page 230: "an ore of copper." + +Changed "factictius" to "facticius" in the footnote on page 233: "Sal +facticius." + +Changed "Interpretaltio" to "Interpretatio" in footnote 13 on page 234: +"Interpretatio, die heffe." + +Changed "Loehneys" to "Lohneys" in footnote 21 on page 237. + +"Cramner" in footnote 21 on page 237 may be a typo for "Cramer," but it +was left as is. + +Changed "neutralized" to "neutralised" in footnote 21 on page 237: +"neutralised by the nitre." + +Changed "notes" to "note" in footnote 33 on page 248: "note 10." + +Changed "liquified" to "liquefied" on page 250: "has become sufficiently +liquefied." + +Changed "touchneedles" to "touch-needles" in footnote 37 on page 253: +"detailed account of touch-needles." + +The reference to page 259 in footnote 39 on page 253 does not seem to +make sense, but was not changed. Perhaps the reference should be to +footnote 27 on page 242. + +In the table on page 257, the entries for the 20th and 21st needles do +not add up, because the entry for the number of sextulae of copper +belongs in the 21st needle, not the 20th. This was corrected. However, +there are other errors in this table, which are not so obvious and were +not corrected. In particular, the entries for the 22nd, 28th and 31st +needles do not add correctly. + +In the table on page 258, the number for the siliquae of copper was +sometimes in the sextulae column. These were corrected. The affected +lines were the ones for needles 13, 22 and 24. There is some other error +(uncorrected) for the 17th needle; probably it should have another +sextula of silver. + +Filled in the missing "4" in the line for the 8th needle in the table on +page 260. + +Changed "52" to "25" in the line for the 3rd weight in the table for the +"greater" weights on page 261. + +Changed "stele" to "stelae" on page 279: "Certain stelae." + +Changed "hanging-wall" to "hangingwall" on page 279: "the hangingwall +rock;" and on page 292: "from the hangingwall." + +Changed "lead" to "led" in the footnote on page 281: "led through a +series." + +Changed "Humpfrey" to "Humphrey" in the footnote on page 283: "William +Humphrey." + +Changed "Erbisdroff" to "Erbisdorff" on page 304: "tin-stuff of +Schlackenwald and Erbisdorff." + +Changed "colleced" to "collected" on page 328: "concentrates are +collected." + +Changed "civilisation" to "civilization" in footnote 17 on page 330: +"glimmer of civilization." + +Changed "Chapter IX" to "Book IX" in footnote 22 from page 350. + +Changed "Thothmes" to "Thotmes" in footnote 6 on page 362: "the time of +Thotmes III." + +Changed "unseasonable" to "unreasonable" on page 374: "yet it is not +unreasonable." + +Inserted "L--" in the caption for the illustration on page 385. + +Footnote 23, p. 391, refers to a note on p. 265, but there is no such +note. + +Changed "carni" to "Carni" in the caption to the illustration on page +393. + +Removed extra right parenthesis at end of footnote 28, from page 396, +and footnote 7, from page 441. + +Changed "Agatharcides" to "Agatharchides" in the footnote on page 399, +and again in the footnote on page 465. + +Changed "bare" to "bars" on page 418: "the lattice-like bars sells." + +Changed "Nütliche" to "Nützliche" in footnote 59 on page 433: "the +Nützliche Bergbüchlein in association." + +Changed "threequarters" to "three-quarters" on page 437: "three-quarters +of a foot." + +Changed "the spout from the opercula extends" to "the spouts from the +opercula extend" in the caption to the illustration on page 446. + +Changed "earthern" to "earthen" on page 451: "melted with copper in a +red hot earthen crucible." + +Changed "Boussingalt" to "Boussingault" in footnote 18 on page 454: +"Investigation by Boussingault." + +Footnote 26, on page 465, refers to a discussion on page 389; there is +no such discussion. Perhaps the note on page 390 was intended, but no +change was made. + +The reference to p. 480 in the footnote on page 466 doesn't seem to make +sense. Perhaps the reference should be to the note on p. 475 or the +illustration on p. 481, but it was not changed. + +Changed "Agricolas'" to "Agricola's" in footnote 27 on page 467. + +Changed "roman" to "Roman" in the caption to the figure on page 481. + +Changed "pinewood" to "pine-wood" on page 496: "shingles of pine-wood." + +Changed "Fore-hearths" to "Forehearths" in the caption to the +illustration on page 508. + +Changed "or" to "of" in the table in footnote 17 on page 512: "564.8 +lbs. of (A)." + +Changed "near-by" to "nearby" on page 526: "in a nearby timber." + +Changed "fore-hearth" to "forehearth" on page 540: "into the +forehearth," and on page 543: "into the forehearth." + +Changed "sideboards" to "side-boards" on page 552: "the side-boards are +fixed." + +Changed superscripts to subscripts in footnote 9 on page 561: +"Ca(NO_{3})_{2} + K_{2}CO_{3} = CaCO_{3} + 2KNO_{3}." + +Changed "crystallised" to "crystallized" in footnote 9 on page 561. + +Changed "hydros" to "hydrous" in the footnote on page 565: "the hydrous +sulphate." + +Changed "octrahedra" to "octahedra" in the footnote on page 565. + +Changed "subtance" to "substance" in footnote 11 on page 572: "that +feathery substance." + +Changed "ventholes" to "vent-holes" on page 580: "two or three +vent-holes." + +Changed "prehistoric" to "pre-historic" on page 582: "from pre-historic +times." + +Changed "Rawlinsons, Trans." to "Rawlinson's Trans." in the footnote on +page 583. + +Changed "Neavius" to "Naevius" on page 596: "Johannes Naevius." + +Changed "Unständliche" to "Umständliche" in footnote 3 on page 599: +"Umständliche ... Chronica." + +Changed "Watts" to "Watt" on page 605: "Watt mentions it." + +Changed "begininng" to "beginning" on page 611: "beginning of the +sixteenth centuries." + +Changed "oxidising" to "oxidizing" on page 615: "an oxidizing blast." + +Changed "Oryguia" to "Orguia" on page 617. + +Changed the reference for Annaberg on page 619 from "XXI" to "XXXI." + +Changed "Ceragurite" to "Cerargurite" in its index entry on page 620. + +Changed "Fibræ" to "Fibrae" (ae-ligature) in its index entry on page +622. + +Changed the reference for Glass on page 623 from "534-592" to "584-592." + +Changed two references for Magnes on page 625 from "584" to "585." + +Changed the reference for Nuremberg, Scale of Weights on page 626 from +"264" to "263." + +Changed "Pickscheifer" to "Pickschiefer" in its index entry on page 626. + +Changed the reference for Proustite on page 626, and the references for +Pyrargyrite, for Ruby Silver, for Silver, for Silver Glance and for +Silver Ores on page 627, from "109" to "108." + +Changed the reference for Quicksilver on page 626 from "111" to "110." + +Changed "Stuices" to "Sluices" on page 626, in the index entry for +"Pockets in Alluvial Sluices." + +Changed the references for Schneeberg, St. George mine and for St. +George Mine on page 627 from "92" to "91." + +Changed "Steinmack" to "Steinmarck" in its index entry on page 628. + +In the Index to Persons and Authorities (starting page 630), there are a +number of references to page 599 that appear to make more sense as +references to 603, but which were not changed. + +Changed the reference for Venice, Scale of Weights on page 630 from +"264" to "263." + +Changed the reference for De Mensuris et Ponderibus, Weights and +Measures on page 632 from "264" to "263." + +Changed the reference for De Natura eorum quae Effluunt ex Terra, +Dedication on page 632 from "VIII" to "VII." + +Changed the reference for De Precio Metallorum et Monetis on page 632 +from "264" to "263." + +Changed "Diphilus" to "Diphilos" in its index entry on page 632. + +Changed the references for Forehearth and for Furnaces, Blast on page +637 from "390" to "389." + +Changed the references for Pumps, Suction on page 638 from "188; 137" to +"183; 187." + +Changed the reference for "Tests" for Refining Silver on page 638 from +"384" to "484." + + + + + +End of the Project Gutenberg EBook of De Re Metallica, by Georgius Agricola + +*** END OF THIS PROJECT GUTENBERG EBOOK DE RE METALLICA *** + +***** This file should be named 38015-8.txt or 38015-8.zip ***** +This and all associated files of various formats will be found in: + https://www.gutenberg.org/3/8/0/1/38015/ + +Produced by Malcolm Farmer, Stephen H. 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