diff options
Diffstat (limited to 'old/44175.txt')
| -rw-r--r-- | old/44175.txt | 4877 |
1 files changed, 4877 insertions, 0 deletions
diff --git a/old/44175.txt b/old/44175.txt new file mode 100644 index 0000000..692aa8b --- /dev/null +++ b/old/44175.txt @@ -0,0 +1,4877 @@ +The Project Gutenberg EBook of Nautical Charts, by G. R. Putnam + +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: Nautical Charts + +Author: G. R. Putnam + +Release Date: November 13, 2013 [EBook #44175] + +Language: English + +Character set encoding: ASCII + +*** START OF THIS PROJECT GUTENBERG EBOOK NAUTICAL CHARTS *** + + + + +Produced by Chris Curnow, Peter Becker and the Online +Distributed Proofreading Team at http://www.pgdp.net (This +file was produced from images generously made available +by The Internet Archive) + + + + + + +--------------------------------------------------------------+ + | Transcriber's Notes | + | | + | Passages in italics are indicated by _italics_. | + | Passages in bold are indicated by #bold#. | + | Superscript text is preceded by a caret, like N^o. | + | [oe] represents the oe-ligature. | + | Small-caps text has been converted to UPPERCASE. | + | Changes in the text are listed at the end of the book. | + +--------------------------------------------------------------+ + + + + +[Illustration: SURVEYING STEAMER _FATHOMER_ IN MANILA BAY. + + (_Frontispiece_) +] + + + + + NAUTICAL CHARTS + + BY + + G. R. PUTNAM, M.S. + + MEMBER OF THE AMERICAN SOCIETY OF CIVIL ENGINEERS + DIRECTOR OF COAST SURVEYS, PHILIPPINE + ISLANDS, 1900 TO 1906 + + _FIRST EDITION_ + FIRST THOUSAND + + NEW YORK + JOHN WILEY & SONS + LONDON: CHAPMAN & HALL, LIMITED + 1908 + + + COPYRIGHT, 1908, + BY + G. R. PUTNAM + + + Stanhope Press + + F. H. GILSON COMPANY + BOSTON, U.S.A. + + + + +PREFACE + + +In preparing the material for a lecture on Charts for Columbia +University, the writer was impressed with the fact that although +nautical charts are mentioned or discussed in many publications, there +was not found any one which covered the general subject of their origin, +construction, and use. In the countries of the world more than a million +copies of such charts are now issued annually. A considerable portion of +the human race is interested directly or indirectly, whether as mariners +or passengers or shippers, in navigation upon the sea. Aside from +supplying a handbook for those who might have a general interest in the +subject, it was thought that a discussion of charts might lead to +further consideration of the principles governing their construction. + +This paper has intentionally been made as non-technical as seemed +feasible in treating a somewhat technical subject. The writer is +indebted to the Coast and Geodetic Survey for various illustrative +material from its archives, and to a number of authors for facts or +suggestions. A list is appended of books and papers which have been +freely consulted, bearing on this and related subjects. + + G. R. P. + + WASHINGTON, D.C., _May 24, 1908_. + + + + +CONTENTS + + + PAGE + + LIST OF BOOKS OR PAPERS BEARING ON NAUTICAL CHARTS + AND RELATED SUBJECTS vii + + CHARTS AND MAPS 1 + + COLLECTION OF INFORMATION FOR CHARTS 31 + + PREPARATION OF INFORMATION FOR CHARTS 67 + + PUBLICATION OF CHARTS 84 + + CORRECTION OF CHARTS 97 + + READING AND USING CHARTS 112 + + USE OF CHARTS IN NAVIGATION 124 + + PUBLICATIONS SUPPLEMENTING NAUTICAL CHARTS 154 + + INDEX 161 + + + + +LIST OF BOOKS OR PAPERS BEARING ON NAUTICAL CHARTS AND RELATED SUBJECTS + + + Periplus, an Essay on the Early History of Charts, and Sailing + Directions. A. E. Nordenskioeld, Stockholm, 1897. + + Maps, their Uses and Construction. G. James Morrison, London, + 1902. + + Charts and Chart Making. Lieut. John E. Pillsbury, U.S.N., in + _Proceedings U. S. Naval Institute, 1884_. + + Principal Facts relating to the Earth's Magnetism. L. A. Bauer, in + U. S. Magnetic Declination Tables, Coast and Geodetic Survey, + 1903. + + Marine Hydrographic Surveys of the Coasts of the World. G. W. + Littlehales, in Report of the Eighth International Geographic + Congress, 1904. + + Smithsonian Geographical Tables. R. S. Woodward, Washington, 1906. + + Admiralty Charts, Abridged list of. Published by J. D. Potter, + London, 1907. + + Military Topography. Capt. C. B. Hagadorn, U.S.A., West Point, + 1907. + + Service Hydrographique de la Marine, Paris, 1900. + + A Manual of Conventional Symbols in Use on Official Charts. United + States Hydrographic Office, Gustave Herrle, 1903. + + Hydrographical Surveying. Admiral W. J. L. Wharton, London, 1898. + + On the Correction of Charts, Light Lists, and Sailing Directions. + Published by J. D. Potter, London, 1904. + + Notes Relative to the Use of Charts. D. B. Wainwright, Coast and + Geodetic Survey, 1900. + + The Law relating to Charts and Sailing Directions. H. Stuart + Moore, London, 1904. + + Notes bearing on the Navigation of H. M. Ships. Hydrographic + Office, London, 1900. + + The Relations of Harbors to Modern Shipping. W. H. Wheeler, in + _Engineering News_, September 6, 1906, New York. + + Wrinkles in Practical Navigation. Capt. S. T. S. Lecky, London, + 1899. + + Navigation and Compass Deviations. Commander W. C. P. Muir, + U.S.N., Annapolis, 1906. + + The Practice of Navigation. Henry Raper, London, 1898. + + Lehrbuch der Navigation. Reichs-Marine-Amt, Berlin, 1906. + + _The Nautical Magazine_, London. + + Dangers and Ice in the North Atlantic Ocean. Bureau of Navigation, + U. S. Navy Department, 1868. + + Reported Dangers in the North Pacific Ocean. U. S. Hydrographic + Office, 1871. + + Pacific Islands, Vol. III, chapter on "Vigias." British + Hydrographic Office, London, 1900. + + Harriman Alaska Expedition, Vol. II, Bogoslof, our Newest Volcano, + by C. Hart Merriam, New York, 1901. + + Expedition to the Aleutian Islands, 1907. T. A. Jaggar, Jr., in + _The Technology Review_, 1907, Boston. + + Recent Changes in Level in the Yakutat Bay Region, Alaska, by R. + S. Tarr and Lawrence Martin, in Bulletin of the American + Geological Society, 1906. + + An Index to the Islands of the Pacific Ocean. W. T. Brigham, + Honolulu, 1900. + + Geography, articles by C. R. Markham, A. R. Clarke, and H. R. Mill + in Encyclopaedia Britannica. + + Development in Dimensions of vessels, Elmer L. Corthell, Tenth + International Navigation Congress, 1905. + + + + +NAUTICAL CHARTS + + + + +CHARTS AND MAPS + + +#Need of maps.# Maps are useful and necessary for many purposes. Only by +means of a correct map or globe can a clear idea of the geography of a +region be given. An attempt to convey the same information by a written +description would in comparison be both cumbersome and obscure. Even by +passing over an extensive region a man unaided by instruments will +obtain only a rather crude notion of the relations, which he could +clearly see on a good map. The importance among the human arts of the +making of maps is indicated by the references to them in very early +historical records, and by the skill in map drawing shown by some of +the primitive peoples of to-day. This skill exists particularly among +races whose mode of life gives them a wide horizon, as for instance the +Eskimos. An interesting instance of this was the case of Joe, an Eskimo +guide, who, in 1898, before the surveys of the Yukon delta were made, +drew a map of the Yukon mouths with much more complete information than +any previously available. + +Without attempting to enumerate in detail the special uses for maps, in +the broader sense they may be said to be essential for commercial, +engineering, military, scientific, educational, and political purposes. + +#Early geography and map making.# The oldest map known is a plan of gold +mines in Nubia, drawn on a papyrus. This is of the thirteenth century +B.C., and was found in Egypt. + +In the earliest historic times men believed the earth to be a flat +surface of nearly circular outline, a natural inference for those with +limited outlook and communication. Later the idea was introduced of the +ocean as a river bounding the earth disk. The spherical theory of the +earth was, however, early accepted by learned men, and was demonstrated +by Aristotle (384 to 322 B.C.), who used as proofs the earth's shadow on +the moon, and the change in the visibility of the stars in traveling +north or south. Crates constructed a terrestrial globe in the second +century B.C. + +There is no Greek or Latin map extant of earlier date than the time of +Ptolemy, but there are references showing that maps were in use. One of +the first of such passages in Greek literature is the interesting +comment of Herodotus written in the fifth century B.C., "but I laugh +when I see many who already have drawn the circuits of the earth, +without any right understanding thereof. Thus they draw Oceanus flowing +round the earth, which is circular, as though turned by a lathe, and +they make Asia equal to Europe." + +A map of the world was drawn by Anaximander, 560 B.C. A hundred years +later Democritus drew a map having an oblong shape, and taught that the +width of the world from east to west was one and a half times its extent +from north to south, a conclusion based on his travels eastward as far +as India. This theory, which was for a time accepted, has left an +enduring mark in the words _longitude_ and _latitude_, originally +signifying the length and the breadth of the earth. + +The first application of astronomy to geography was made by Pytheas, who +about 326 B.C. obtained the latitude of Marseilles by an observation of +the altitude of the sun. Dicearchus in 310 B.C. determined the first +parallel of latitude by noting places where on the same day the sun cast +shadows of equal length from pillars of equal height. Eratosthenes (276 +to 196 B.C.) was the first to compute the circumference of the earth +from observations of the altitude of the sun at Alexandria and at Syene +in Upper Egypt and an estimation of the distance between these two +places. Ptolemy, a Greek of Alexandria, in the years from 127 to 151 +A.D. wrote extensively on geographic subjects, and collected into +systematic form all geographic knowledge then existing; he was the +greatest geographer of early history. + +In the ten centuries which followed, part of the early advance in this +science was obscured, and the theory that the earth was a flat disk +surrounded by the sea again became prevalent. The voyages of discovery +of the middle ages, however, led to a rapid development of geographic +knowledge. + +The flattening of the spherical earth was not suspected until in 1672 a +clock regulated to beat seconds at Paris, when taken to Cayenne near the +equator was found to lose two and one-half minutes a day. Newton proved +that this was due to the fact that the earth is an oblate spheroid. In +1735 accurate measurements were undertaken to determine the size and +shape of the earth. The equatorial diameter has been found to be 7926.6 +miles and the polar diameter 7899.6 miles, the difference, or 27 +statute miles, being the amount of the flattening at the poles. + +#The first sailing directions.# The early Greek and Roman writers do not +allude to charts or maps intended especially for the use of seafarers. +There are, however, extant several peripli or descriptions of the coast. +Some of these appear certainly to have been intended for use as nautical +guides, corresponding to the modern sailing directions. It is probable +that they were explanatory of or accompanied by coast charts, now lost. +They are of interest therefore as being probably the first compilations +for the guidance of seamen. One of the earliest, written apparently in +the fifth and fourth centuries B.C., is entitled "Scylax of Caryanda, +his circumnavigation of the sea of the inhabited part of Europe and Asia +and Libya." It contains a systematic description of the coasts of the +Mediterranean, Black Sea, and part of the west coast of Africa. The +following are some extracts which indicate the character of the work. It +is to be noted that no bearings are given, and that distances are +usually stated by day's sail: Africa is referred to as Libya. + +"Europe. I shall begin from the Pillars of Hercules in Europe and +continue to the Pillars of Hercules in Libya, and as far as the land of +the great Ethiopians. The Pillars of Hercules are opposite each other, +and are distant from each other by one day's sail.... From Thonis the +voyage to Pharos, a desert island (good harborage but no drinking +water), is 150 stadia. In Pharos are many harbors. But ships water at +the Marian mere, for it is drinkable.... From Chersonesus is one day's +sail; but from Naustathmus to the harbor of Cyrene, 100 stadia. But from +the harbor to Cyrene, 80 stadia; for Cyrene is inland. These harbors are +always fit for putting into. And there are other refuges at little +islands, and anchorages and many beaches, in the district between.... +After the isthmus is Carthage, a city of the Ph[oe]nicians, and a +harbor. Sailing along from Hermaea it is half a day to Carthage. There +are islands off the Hermaean cape, Pontia island and Cosyrus. From Hermaea +to Cosyrus is a day's sail. Beyond the Hermaean cape, towards the rising +sun, are three islands belonging to this shore, inhabited by +Carthaginians; the city and harbor of Melite, the city of Gaulus, and +Lampas; this has two or three towers.... The sailing along Libya from +the Canopic mouth in Egypt to the Pillars of Hercules ... takes 74 days +if one coast round the bays.... From the cape of Hermaea extend great +reefs, that is, from Libya towards Europe, not rising above the sea; it +washes over them at times.... From Thymiateria one sails to cape +Soloes, which juts far into the sea. But all this district of Libya is +very famous and very sacred.... This whole coasting from the Pillars of +Hercules to Cerne Island takes twelve days. The parts beyond the isle of +Cerne are no longer navigable because of shoals, mud, and sea-weed. This +sea-weed has the width of a palm, and is sharp towards the points, so as +to prick." + +That there were many other similar writings in the following centuries +is shown by the following quotation from Marcianus, in a preface to +sailing directions written in the fifth century A.D.: "This I write +after having gone through many sailing directions, and spent much time +on their examination. For it behooves all who are men of education, to +scrutinise such attempts at learning in this subject, so as neither +rashly to believe the things that are said, nor incredulously to set +their private opinions against the careful decisions of others." + +The oldest extant sailing directions of the middle ages bear date 1306 +to 1320. + +#Development of chart making.# The application of the compass to +nautical use in the twelfth century A.D. had a marked effect in +encouraging voyages of exploration, and therefore indirectly on chart +making. The following, written toward the close of the twelfth century, +is the first known mention of the use of the compass in Europe: "The +sailors, moreover, as they sail over the sea, when in cloudy weather +they cannot longer profit by the light of the sun, or when the world is +wrapped in the darkness of the shades of night, and they are ignorant to +what part of the horizon the prow is directed, place the needle over the +magnet, which is whirled round in a circle, until, when the motion +ceases, the point of it (the needle) looks to the north." The nautical +compass of that time appears to have consisted of a magnetized needle, +floated in a vessel of water by a cork or reed, and having no index nor +compass card. Peregrinus in 1269 made notable improvements in the +compass, including a pivot suspension for the needle, a graduation, a +lubber line, and an azimuth bar for sighting on the sun or other object. + +Nautical charts are known to have been in use since the thirteenth +century A.D., but the earliest extant of which the date can be fixed is +Vesconte's loxodromic chart of 1311. + +The loxodromic charts first appeared in Italy, and were so called from +the fact that they were crossed by loxodromes (or rhumb lines) radiating +from a number of crossing points distributed regularly over the map. +Compass roses carefully drawn were later added at these crossing points, +the first appearing on a chart of 1375. The earliest known mention +of the variation of the compass from true north was on the first voyage +of Columbus, who discovered this important fact in 1492, and as a +consequence his "seamen were terrified and dismayed." Before that time +it was assumed in Europe that the compass pointed "true to the north +pole." The apparent failure to detect the variation earlier was +doubtless to some extent due to its small amount at that time along the +Mediterranean. The earlier charts showed both lines and compass roses +apparently oriented with the true meridian, though there is some +evidence to indicate that they were actually oriented with the magnetic +meridian, the designer not recognizing any difference. The variation of +the compass was first marked on a map in 1532 and on a printed chart in +1595, but the placing of magnetic compasses on charts did not become +customary until about fifty years ago. These early charts were drawn on +parchment, using bright colors. They were copied by hand, one from +another, with gradual variations. They had no projections, and the +draftsmen evidently had no idea of the sphericity of the earth. Islands +and points were usually exaggerated; shallows were indicated, but no +soundings; no information was given as to the interior of the countries; +a scale of distances was nearly always provided. + +Charts were first printed about 1477, and are known to have been +engraved on copper by 1560. + +The maps of Ptolemy were ruled with degree lines, but no chart was so +provided until 1427; by 1500, however, most charts were graduated. +Before this date it is not known on what projection the charts were +constructed. On the first graduated charts the degree lines were +equidistant parallel straight lines cutting each other at right angles +and thus dividing the chart into equal squares or rectangles. These were +known as "plain charts." This square projection had little to commend it +save simplicity of construction, as in higher latitudes it gave neither +directions nor distances correctly. The difficulties of its use in +navigation were early recognized, and nautical works contained chapters +on "sailing by the plain chart, and the uncertainties thereof." + +The example of early chart making shown in Fig. 2 is of great interest +as being the earliest extant chart which includes America. This chart +was drawn on ox-hide in 1500 by Juan de la Cosa, who accompanied +Columbus on his first voyage as master of his flagship, and on his +second voyage as cartographer. The chart, of which only a portion is +shown here, purports to cover the entire world; it joins Asia and +America as one continent, the Pacific Ocean being then still unknown. + +[Illustration: FIG. 2. CHART OF NORTH ATLANTIC OCEAN,] + +Gerhard Kraemer, a Flemish map-maker, better known by his Latin name of +Mercator, in 1569 published his famous Universal Map. In this map the +meridians and parallels were still straight lines intersecting at right +angles, but the distances between the parallels were increased with +increasing latitude in such proportion that a rhumb line, or line +cutting the meridians at a constant angle, would appear on the map as a +straight line. Mercator never explained the construction of his chart, +and as the above condition was not accurately carried out, it is thought +that the chart was drawn by comparing a terrestrial globe with a "plain +chart." After examination of a mercator chart in 1590, Edward Wright +developed the correct principles on which such a chart should be +constructed, and published in 1599 his treatise "The Correction of +Certain Errors in Navigation." It took nearly a century to bring this +chart into use, and even in the middle of the eighteenth century +nautical writers complain that "some prefer the plain chart." + +[Illustration: BY JUAN DE LA COSA, 1500. EARLIEST EXTANT CHART SHOWING +AMERICA.] + +The Arcano del Mare, 1646, was the first marine atlas in which all the +maps were drawn on the mercator projection. + +In the sixteenth, seventeenth and eighteenth centuries charts and +sailing directions were often bound together in large volumes. These +usually had quaint titles, not overburdened with modesty, of which the +following is an example: "The Lightning Columne, or Sea-Mirrour, +containing the Sea-Coasts of the Northern, Eastern, and Western +Navigation. Setting forth in divers necessaire Sea-Cards, all the Ports, +Rivers, Bayes, Roads, Depths, and Sands. Very curiously placed on its +due Polus height furnished. With the Discoveries of the chief Countries +and on what Cours and Distance they lay one from another. Never there to +fore so Clearly laid open, and here and there very diligently bettered +and augmented for the use of all Seamen. As also the situation of the +Northerly Countries, as Islands, the Strate Davids, the Isle of Jan +Mayen, Bears Island, Old Greenland, Spitsbergen and Nova Zembla. +Adorneth with many Sea-Cards and Discoveries. Gathered out of the +Experiences and practice of divers Pilots and Lovers of the famous Art +of Navigation. Where unto is added a brief Instruction of the Art of +Navigation, together with New Tables of the Sun's Declination, with a +new Almanach. At Amsterdam. Printed by Casparus Loots-Man, Bookseller in +the Loots-Man, upon the Water. Anno 1697. With Previlege for fiftheen +years." + +In 1633 a cartographer was appointed to the States-General of Holland, +and it was his duty to correct the charts from the ships' logs. The +Dutch at an early date made important progress in publishing charts. In +1720 there was established in Paris by order of the king, a central +chart office ("depot des cartes et plans, journaux et memoires +concernant la navigation"), and in 1737 the first charts were published +by this office. Detailed surveys of the coast of France were commenced +in 1816. + +In 1740 "the commissioners for the discovery of longitude at sea" were +authorized by Parliament to expend money on the survey of the coasts of +Great Britain, this commission having been created in 1713. Various +rewards were offered by this commission, including one of L10,000, for +the discovery of a method of determining the longitude within 60 miles, +an interesting side light on the uncertainties of navigation at that +time. Compensated timepieces, which have been so important a factor in +improving navigation, were invented by Harrison about 1761. + +[Illustration: FIG. 3. LOXODROMIC CHART OF NORTH ATLANTIC OCEAN, 1565. A +PLAIN CHART WITH LATITUDE DEGREES OF EQUAL LENGTH.] + +In 1795, by an Order in Council, a Hydrographical Office was established +in London, "to take charge and custody of such plans and charts as then +were, or should thereafter be, deposited in the Admiralty, and to select +and compile such information as might appear to be requisite for the +purpose of improving navigation." This office had at first one assistant +and one draftsman. Before that time many charts of a private or +semiofficial character had been published; the catalogue of the East +India Company in 1786 included 347 charts. + +In 1807 the Congress of the United States authorized the President "to +cause a survey to be taken of the coasts of the United States, in which +shall be designated the islands and shoals, with the roads or places of +anchorage, within twenty leagues of any part of the shores of the United +States; and also the respective courses and distances between the +principal capes, or headlands, together with such other matters as he +may deem proper for completing an accurate chart of every part of the +coasts within the extent aforesaid." This law was the origin of the +present United States Coast and Geodetic Survey, now under the +Department of Commerce and Labor. + +In 1841 a systematic survey of the Great Lakes was commenced; this is +the Survey of the Northern and Northwestern Lakes, briefly known as the +Lake Survey, conducted under the Corps of Engineers. + +In 1866 the United States Hydrographic Office was established under the +Navy Department "for the improvement of the means for navigating safely +the vessels of the Navy, and of the mercantile marine, by providing +under the authority of the Secretary of the Navy, accurate and cheap +nautical charts, sailing directions, navigators, and manuals of +instructions for the use of all vessels of the United States, and for +the benefit and use of navigation generally." + +#Systematic surveying and chart making# date back little more than a +century, and most of the information shown on modern charts has been +gathered in that time. At present all the principal maritime nations of +the world have made, or are extending, careful surveys of their own +coasts. + +Several of the countries have added valuable contributions in the +examination of other regions and oceanic areas beyond their borders. The +maritime and colonial interests of Great Britain impelled that nation to +carry on extensive surveys along coasts whose inhabitants were not +prepared to do this work in the earlier days; the British have made +surveys along the coasts of Asia and Africa and a part of South America, +and the resulting charts have been a very important and not sufficiently +known contribution to commercial intercourse among the nations, as well +as to geography. + +The Dutch, French, Spanish, and other European governments have made +nautical surveys in various parts of the world, largely in connection +with their own colonies, and in recent years much useful work has been +done by vessels of the German government. The United States has also +beyond its own territory made valuable additions to hydrographic +knowledge in the work of officers of the Navy in a number of oceanic +exploring expeditions, and surveys on the coasts of Mexico and in the +West Indies, and in the explorations of Fish Commission vessels. + +[Illustration: FIG. 4. EARLY CHART OF NEW YORK HARBOR, 1737.] + +#Extension of maritime surveys.# Of the total area of the earth's +surface, 51,886,000 square miles is land and 145,054,000 square miles is +sea. The oceans thus occupy nearly three-fourths of the whole surface, +affording highways open to the nations. To conduct international +commerce by water the ships of one country must enter the ports of +another. Thus both on the open sea and in the harbors there is an +interest, common to seamen of all nationalities, in the advance of +marine surveys and in the publication of charts. + +To keep the coasts properly charted, as well as lighted and buoyed, is +an obligation devolving on modern nations, not only for the benefit of +their own commerce but for that of other countries. + +As shown below, only a small part of the coast line of the world is +thoroughly surveyed. In the extensive ocean areas which are dotted with +islands or reefs, a large amount of work is required for their +sufficient charting, although many doubtful areas have been cleared up +in recent years. Even the parts that are known to be of depths so great +as to be free from navigational dangers should be sounded over +sufficiently to develop the general configuration of the ocean bottom. + +Through international understanding a thorough exploration of all the +water area of the globe and the coasts may in time be effected, and the +many doubtful spots which still disfigure the charts may be either +eliminated or definitely located. + +#Present state of progress of hydrographic surveys.# A comparatively +small proportion of the coasts of the world can be considered as +completely surveyed at the present time, and even such regions require +much additional revision. In the class of more thoroughly surveyed +coasts should be included the Atlantic and most of the Pacific coast of +the United States, Porto Rico, nearly all the coasts of Europe, Algeria, +and portions of the coasts of Japan, the Philippine Islands, and India. + +A large part of the world's coasts has been surveyed incompletely, but +sufficiently well to permit the publication of navigational charts. This +is the condition as respects most of southeastern Alaska and some other +portions of the Alaskan coast, British Columbia, most of Mexico, Central +America, the West Indies, Brazil and parts of Chile, the Hawaiian +Islands, China, Malay Peninsula, Siam, the Dutch East Indies, Australia, +New Zealand, Persia, Arabia, most of Africa, Iceland, northern +Scandinavia, and Finland. + +Another considerable portion of the coasts has not been surveyed, but +has been covered by explorations which have been embodied in nautical +charts of varied degrees of incompleteness. In this class are the north +coast and considerable portions of the south and west coasts of Alaska, +the Aleutian Islands, Siberia, most of the oceanic groups in the +Pacific, the northern coasts of Europe and North America, Greenland, the +west coast of South America, Venezuela, and Argentina. + +Only a very small proportion of the total length of coasts is now +entirely unexplored, and such portions are confined to the polar +regions. + +#Chart publications of various nations.# There are about eighteen +nations publishing navigational charts, and adding to the information on +which charts are based. Many of these nations republish to some extent +the charts prepared by the others. Great Britain has kept up a series of +charts covering all parts of the world and practically including in some +form all information published elsewhere. This series now (1908) +includes 3725 different charts, of which the annual issue is about +600,000 copies. France (1906) publishes 2948 different charts. + +In the United States, charts are published by the Coast and Geodetic +Survey for the coasts and tidal waters of the main country and the +insular possessions, by the Hydrographic Office for oceanic areas and +foreign coasts, and by the Lake Survey for the Great Lakes. The total +number of different charts issued by these bureaus is about 2300, and +the total annual issue is about 225,000 copies. + +#Systems in use on various charts.# + +_Longitude._ The first chart of New York, published by the Coast Survey +in 1844, was referred to the City Hall of New York as the initial +longitude, and some years ago it was the prevailing custom for each +nation to use a local initial longitude. While this satisfied local +pride it led to much geographical and navigational confusion. Happily +the charts of all countries are now referred to Greenwich, with the +following exceptions: + + France refers to Paris, which is 2 deg. 20' 15'' E. of Greenwich. + Spain refers to San Fernando, which is 6 deg. 12' 20'' W. of Greenwich. + Portugal refers to Lisbon, which is 9 deg. 08' 24'' W. of Greenwich. + +_Units for depths._ The English fathom or foot is used for depths on the +charts of Great Britain, the United States, and Japan. Russia uses the +sajene of seven English feet. On the modern charts of practically all +the other countries the meter is used, though on older charts various +units are found. + +In the first group feet are ordinarily found only on large scale or +local charts of areas with moderate depths, and the other charts are in +fathoms, except that on the earlier charts of the Coast and Geodetic +Survey feet were used on a sanded surface inside of the three-fathom +curve and fathoms on the white surface outside of that curve. Heights +are stated in feet on the charts of the first group. + +_Plane of reference._ As the depth of water varies with the tide, it is +necessary for charting purposes to adopt some standard plane to which +the soundings are referred. Practically all countries have adopted for +this purpose a low stage of the tide, as this is obviously on the side +of safety; in most cases an extreme low water is used, so that the +actual depths will seldom, owing to the tide, be less than those shown +on the chart. The definite reference planes used on the American charts +will be mentioned later. + +On nearly all charts heights are referred to mean high water, doubtless +owing to this being the visible limit of the land at high tide. On +topographic maps of the interior, the heights are referred to mean sea +level, which plane is of course lower than the preceding by one-half the +range of tide. + +_Symbols on charts._ Fair uniformity as to general principles, with +differences as to details in carrying them out, exists on the various +series of charts regarding their general arrangement and the more +important symbols, such as in the shading of land to distinguish from +water, the use of depth curves, the representation of hills by shade or +contour, the indication of shoals and dangers, and of lighthouses and +buoys. + +#Desirability of uniformity in charts.# Ships engaged in international +commerce must enter foreign ports. As the information is constantly +changing and charts are being corrected or improved, it is sometimes +desirable for the navigator to consult the local foreign charts, and it +may often be necessary for him to carry in his chart room the charts of +several different countries. There are therefore important advantages in +international uniformity in chart publication. + +There should be a common initial longitude, and as the longitude of +Greenwich has been so extensively adopted, it appears quite probable +that its use may some day become universal. + +A common unit for soundings and heights would be very desirable, but the +fact that a large group of nations has united on the metric system, +while a small group with great commercial interests retains another +system, makes the attainment of uniformity difficult. + +Substantial agreement as to the use of symbols on charts, particularly +such as represent aids or dangers to navigation, would be desirable and +doubtless feasible. + +#Privately published charts.# Many of the earlier charts were prepared +and published by private enterprise, and such charts are still +published, as, for instance, the so-called "blue-back" charts printed in +London. These charts have usually differed from those published by the +various governments either in representing the main features in a very +bold manner with little detail or in including a considerable area with +many plans on a single large sheet backed for permanency. An objection +to the latter is that the durability together with the high price tends +to keep an old chart in use long after it is out of date. It would be +financially difficult for a private firm to give the service that a +government does in the matter of correcting the charts and issuing new +editions, and this is an important consideration in the selection of +charts. + +#Purpose of charts.# The main purpose of charts is to furnish graphical +guides to aid in taking a vessel safely from one port to another; they +are maps for the use of navigators. An experienced mariner may be able +to steer his vessel over a familiar course without charts, but this does +not make their publication less necessary. Even such an expert pilot +doubtless studied the charts in the first place; the uncertainties of +the sea and the changes of information are such that his vessel's +equipment should include the latest charts, and safety requires their +examination. The passengers and the merchants who intrust their lives or +their goods to the sea are largely dependent upon the correctness of the +charts. + +Besides their main purpose charts fill many other needs, among which +are; for preliminary planning of harbor improvements and various +engineering works, for defensive works and other military uses, for the +fishing interests, and for general information as to the coastal +regions. Charts will furnish much of interest and instruction to the +traveler by sea and the dweller near the coast, who will learn to read +them. Passenger steamers should more often for the interest of their +patrons display charts of the waters traversed. No written or verbal +description can give as clear an idea of geographical features and +relations as a good map or chart. + +As the charts are revised from time to time, a comparison of editions at +different dates furnishes a record of the changes wrought by nature or +man, and this is especially useful in studying the action in many harbor +and river entrances, as well as for historical purposes. + +#Requirements for charts.# As charts are maps of the water areas, +including the adjoining land, and intended primarily for the use of +mariners, they differ in important respects from topographic maps or +general maps, even such as include the water areas. The main +requirements for charts are these; correct and complete information, +early publication of new data, clear and intelligible representation of +the information, convenient arrangement as navigational instruments, and +high standard of publication. + +The special and sometimes difficult conditions under which charts must +be used on shipboard call for good judgment throughout their +preparation. Even the paper on which they are printed is of importance, +in order that they may be sufficiently durable and suitable for +plotting. + +#Information given on charts.# It is evident that it is impossible to +represent on a chart of any practicable scale all the features that +exist on the corresponding area of the earth's surface. It is +essential, therefore, that a selection be made of the classes of facts +that are to be shown, as well as of the detail that is to be used for +each class. The practical utility of the chart depends largely on the +good judgment used in this selection. In the information shown, charts +differ from maps principally in representing by soundings and curves the +configuration of the bottom of the water area, and in showing ordinarily +the topographic features only in the vicinity of the coast line. + +The convenience of mariners should govern in the selection and +arrangement of the information to be shown on charts, though they may be +made useful for other purposes so long as this convenience is not +lessened. The needs and preferences of navigators alone, however, differ +so much that a reasonable chart must be somewhat of a compromise between +conflicting views. For certain classes of navigation a boldly drawn +chart showing only the dangers and a few other soundings and some +landmarks might be useful. For other maritime purposes a more detailed +chart would be valuable. The first, however, would fail to give facts +often demanded in the navigational use of the chart, and the second if +carried to an extreme would make a chart difficult to use. + +[Illustration: FIG. 5. STATE OF ADVANCEMENT OF HYDROGRAPHIC SURVEYS OF +THE COASTS OF THE WORLD, 1904. + + _By G. W. Littlehales._ +] + +Shoals and dangers are shown either by the least depth or by rock or +reef symbols. The characteristic soundings are shown on the chart, with +abbreviations indicating the nature of the bottom. Depth curves are +drawn, joining together points of like depth, and inclosing areas of +less depth, on the same principle that contours are used on land maps; +usually also the shoaler spots are made more prominent by sanding or +tinting the area within them. Lighthouses, buoys, and other artificial +aids to navigation are represented, with descriptive abbreviations. The +coast is shown by a bold solid line for high water and a dotted line for +low water. The main topographic features are represented for a moderate +distance from the coast, with such detail as is useful, depending on the +scale of the chart. Elevations are given in figures for prominent +summits, islands, and rocks; the general configuration of hills and +mountains is represented by contours on large scale charts or by +hachures or shading on small scale charts. Rivers, streams, lakes, +marshes, towns, roads, prominent buildings, and other important +topographic features are shown by appropriate symbols. It is important +that objects which may be useful in navigation as landmarks, whether +natural or artificial, be plainly shown and described, if necessary to +their identification, and that they should not be obscured by details of +lesser importance. On the larger scale charts only, vegetation features, +particularly areas covered by trees, are represented by symbols. The +land area is usually clearly distinguished from the water area by a tint +or stipple. Latitude and longitude are given by the projection +lines and the subdivided border, or sometimes on harbor plans by a note +giving the position of some one point. Brief information as to the time +and range of the tides is stated in a note. Data regarding currents, +whether due to tidal or other causes, are given by current arrows placed +on the chart, or by explanatory notes. Compasses are for convenience +printed on the charts, and data given as to the magnetic variation and +its rate of change. On large scale charts scales are provided for use in +measuring distances. Ranges and channel lines are given when required. +The ports are indicated where storm warning signals are displayed. The +areas of forbidden anchorages are shown, and when important, the +positions of submarine cables. The lines dividing the high seas from +inland waters are sometimes stated on United States charts. Life saving +stations are given, and time balls are usually noted. Views of important +features are shown on some charts. + +[Illustration: FIG. 6. SYMBOLS USED ON CHARTS OF THE UNITED STATES COAST +AND GEODETIC SURVEY.] + +The layman who looks at the printed chart probably does not appreciate +the amount or the variety of information that must be gathered and +sifted and put in proper shape for a single chart. + + + + +COLLECTION OF INFORMATION FOR CHARTS + + +#Need of thorough surveys.# As has been stated, a good chart requires +that a thorough and correct survey be first made of the region to be +charted. It is said that men are very apt to accept as true anything +they see on a map. As to the nautical chart the mariner is likely to be +somewhat more critical, however, and it is well that he is. The +difficulty of charting an invisible surface such as the bottom of the +sea is great, and the proportion of the navigable waters surveyed in +sufficient detail to be at all certain of the absence of uncharted +dangers is small. + +The planning of surveys in a new region, such, for instance, as the +Philippine Islands, presents many interesting problems, on the solution +of which the effectiveness in chart results and the cost of the work +materially depend. Many local conditions must be taken into account. The +surveys are made on opposite coasts according to the seasonal winds and +rainfall. In some parts fair-sized steamers are necessary; in others +launches and small boats can do the work more economically. Shore +parties with land transportation are used for portions of the work where +the country permits. Natives are employed as far as practicable for the +classes of work they can do; the Filipinos, for instance, make good +sailors on the vessels and excellent penmen in the office. + +The following is a brief outline of the steps of a complete survey for +charting purposes, according to the present practice of the United +States Coast and Geodetic Survey. These are given in their logical +order, though in actual work this order must often be departed from. In +this Survey the methods of control have been of a high standard; that +is, the main stations have been accurately determined and permanently +marked and described, and this has proven an advantage in the +joining together of the original surveys and resurveys. + +#Astronomical observations.# To locate on the surface of the earth the +area to be charted, astronomical observations are required for the +latitude and longitude of one or more points. In the best practice the +longitude of a point is obtained by observing the transits of stars to +get the local time, and sending time signals by telegraph to obtain the +difference from the local time of some other place whose longitude is +known. The latitude is observed by measuring the difference of zenith +distance of pairs of stars crossing the meridian north and south of the +zenith. The azimuth or true direction of some line is also obtained from +star observations, usually by observations with a theodolite on a +circumpolar star. Much existing chart work depends on positions +determined by less accurate methods, as, for instance, longitudes +obtained by transporting chronometers between the known station and that +to be determined, or by observations of moon culminations, and latitudes +obtained by direct observations of the altitudes of stars with +theodolite or sextant. + +[Illustration: FIG. 7. SYMBOLS USED ON CHARTS OF THE BRITISH +HYDROGRAPHIC OFFICE.] + +[Illustration: FIG. 8. TRIANGULATION OF A BAY, SHOWING LOCATION OF +SURVEY SIGNALS AND LANDMARKS.] + +#Triangulation.# The main framework of the survey consists of a series +of triangles connecting prominently located points which are permanently +marked in the ground and the location described so that they can be +found at a future time. At long intervals in the survey base lines are +laid out and carefully measured with steel tape. Signals are erected +over the points, including those at the ends of the base line, and +angles are then measured at the various stations. From the measured +length of the base and the angles the lengths of the sides of the +triangles are computed, and from these lengths and the latitude and +longitude of one point the latitudes and longitudes of all the other +points are obtained. When several astronomically determined points are +connected by such a triangulation a complication arises from what is +known as "deflection of the plumb line," which is the angular amount by +which the actual sea-level surface of the earth departs from the +symmetrical figure of revolution, owing to the variations in the density +of the earth's outer layers. The distance between two points as measured +by triangulation thus differs from the distance computed from the +astronomically determined positions. If this irregularity were not taken +care of by adopting mean positions, the discrepancy in joining up +different surveys would in extreme cases amount to about half a mile. + +[Illustration: FIG. 9. TRIANGULATION STATION AND SIGNAL, ON ALASKA +COAST.] + +[Illustration: FIG. 10. MEASURING ANGLES WITH THEODOLITE AT +TRIANGULATION STATION ON ALASKA COAST.] + +#Survey sheets# are next prepared, of suitable size and scale. On each +sheet a projection is laid down, that is, the meridians and parallels +are drawn, and all the points determined in the triangulation are +plotted in their true relation. Usually separate sheets are prepared for +the topography or shore survey and for the hydrography or survey of the +water area. + +#Topography.# The topographic survey of the shore and as much of the +adjacent area as is required is usually made with a plane table, on +which the map is actually drawn in the field as the work progresses. +Points are located on the plane table sheet either by direct reading of +the distance on a stadia rod or by intersections from two or more +stations. On the plane table sheet it is customary to locate the shore +or high-water line, the low-water line, off-lying rocks, streams, +rivers, roads, towns, lighthouses, and all prominent features near the +coast. Elevations are measured with the plane table or obtained from the +triangulation, and are represented on the sheet both by figures and by +contours, which are lines joining together points of the same elevation. +For instance, a 100-foot contour represents the line where a plane 100 +feet above sea level would cut the surface of the ground. It is +particularly important in this topographic work to locate accurately +objects which are good landmarks and likely to be of use to the mariner. +In some regions auxiliary methods are used in filling in the topography, +as, for instance, along a difficult coast each feature of importance may +be located by sextant angles, or a traverse line may be run along the +shore by the transit and stadia method. + +[Illustration: FIG. 11. TOPOGRAPHIC SURVEY PARTY AT WORK WITH PLANE +TABLE ON THE PRIBILOF ISLANDS.] + +[Illustration: FIG. 12. SURVEY SIGNAL OF IRON PIPE ON THE BAR OFF THE +MOUTH OF THE YUKON RIVER.] + +#The hydrography,# or the survey of the water area, is of prime +importance for the chart, but in the order of prosecution of the work it +is convenient but not essential that it come after sufficient points +have been located by the triangulation and topography. A hydrographic +sheet is prepared on which all the points are plotted which will be +useful. A system of sounding lines is then run over the entire area to +be surveyed, locating the position of the sounding boat at intervals by +sextant angles on survey signals or by angles from the shore. The +ordinary method of sounding is to cast a lead from a boat and read the +depth when the lead touches bottom and the line is vertical, and make +note of the nature of the bottom. There is a systematic spacing between +the casts of the lead and between the lines passed over by the boat, +depending on the depth of water and character of the bottom. For +soundings in deeper water various forms of sounding machines are used, +with weight attached to a wire. For very great depths a small steel wire +is employed and the weight is detached and left on the bottom. The +deepest sounding thus far made, 5269 fathoms, or nearly six miles, was +obtained by this method in the Pacific Ocean near Guam. + +[Illustration: FIG. 13. HYDROGRAPHIC PARTY SOUNDING WITH LAUNCH IN +BALTIMORE HARBOR.] + +[Illustration: FIG. 14. THE LUCAS AUTOMATIC SOUNDING MACHINE FOR DEPTHS +TO 5000 FATHOMS, WITH ENGINE.] + +[Illustration: FIG. 15. THE SIGSBEE SOUNDING MACHINE ON A SURVEYING +VESSEL.] + +[Illustration: FIG. 16. LONGITUDINAL SECTION OF SURVEYING STEAMER +_FATHOMER_, SHOWING GENERAL ARRANGEMENTS.] + +The offshore soundings are made from a surveying steamer; the inshore +work is usually done by a launch or small boat. + +So far as the navigational use of charts is concerned it is important +that the hydrography shall show the limiting depths and the freedom from +dangers, of channels, entrances, harbors, and anchorages. It is also +desirable that the soundings shall be carried off shore at least as far +as the one-hundred-fathom curve, as with the modern forms of +navigational sounding machines it is possible for vessels under way to +obtain soundings to this depth, and such soundings may be of value in +identifying the location of the vessel. For depths greater than one +hundred fathoms the soundings have less direct value to navigation +except as proving the absence of shoaler areas, but soundings throughout +the oceanic regions are of great geographical interest as well as of +direct practical value in the laying of cables. + +It is obvious that the plan of mapping the sea bottom by dropping a lead +at intervals over its hidden surface is far from an ideal one. The lead +gives the depth only at the point at which it touches the bottom, and no +information as to the space between the casts except such as may be +inferred from the relation of successive soundings. In numerous cases, +after what was considered a very thorough survey of a region had been +made, at some later day a pinnacle rock or other danger has been +discovered. For instance, a very detailed hydrographic survey of +Buzzards Bay was made in 1895; the sounding lines were run at intervals +of 50 to 100 yards, and 91,000 soundings were made for a single sheet. +Within this area the cruiser _Brooklyn_ in 1902 touched a rock which +was found to have 18 feet over it. (Fig. 17.) The least depth in the +vicinity developed in the original survey was 31 feet. + +For the satisfactory development of hydrographic work some invention is +much needed which as it passes along the bottom will give a continuous +depth curve. Several devices have successfully accomplished this in +shoal water, but great credit awaits the inventor who designs something +of more general application. + +[Illustration: FIG. 17. PORTION OF ORIGINAL HYDROGRAPHIC SHEET, BUZZARDS +BAY, ON SCALE 1-10000, SHOWING AREA CLOSELY SOUNDED IN 1895, WHERE THE +_BROOKLYN_ STRUCK IN 1902.] + +#Tides and currents.# Information must be obtained as to the movement of +the water, both vertical and horizontal. The rise and fall of the tide +are obtained by tide gauges, either automatic, which draw a continuous +tidal curve on a roll of paper, or simple tide staffs, which must be +read at intervals. The currents, whether due to the tides or other +movements, are measured by noting the movement of partially submerged +floats. Less accurate but useful information as to currents is obtained +from the logs of vessels. + +[Illustration: FIG. 18. DRAGGING FOR DANGERS WITH A LONG WIRE.] + +#Dragging for dangers# has long been resorted to for the investigation +of isolated spots. A valuable and successful means has been employed +recently of making sure that an area is free from shoals or rocks having +less than a certain depth. This is done by dragging through the water a +wire from 500 to 1400 feet long, and suspended at the required depth, +with suitable buoys and weights, and kept taut by the angle of pull. If, +for instance, the wire is set at a depth of 30 feet it will indicate the +presence of any obstruction of less depth by catching on it and +upsetting the buoys, and such spots are at once marked and investigated. +Considerable work has been done with such drags in the last few years on +the Atlantic and Gulf coasts and on the Great Lakes. This is of course a +somewhat tedious process and gives no information as to depths greater +than that for which the wire is set, but the experience already had +indicates its great value. It will probably be found desirable in time +to thus drag all water areas important to navigation where the depth is +near the draft of vessels and the irregular nature of the bottom gives +indication of dangers. In extensive dragging operations near Key West +and in Jericho Bay, Maine, a number of shoals have been picked up which +were not found in the original surveys. + +A remarkable instance of the value of the drag was the recent discovery +of a rock in Blue Hill Bay on the coast of Maine. This rock has but 7 +feet of water over it, and is only 6 feet in diameter at the top. It is +surrounded by depths of 78 feet, from which it rises nearly +perpendicularly. The original survey gave no indication of a danger +here, and its existence was not suspected until it was discovered with +the wire drag. + +Another method of dragging that has been employed is by means of a pipe +suspended beneath a ship's bottom. + +#Magnetic variation.# As the compass is a universal navigational +instrument, information as to the magnetic variation is needed for the +charts. The angle between the direction of the magnetic needle and the +true north is measured at various points on both land and sea, and at +some stations these observations are repeated after a number of years. +From these results magnetic maps are made, from which both the variation +and its annual change may be taken. + +#Reports of dangers.# Aside from the more systematic surveys as outlined +above, much information has been placed on the charts from other +sources. On the earlier charts and on those of more remote regions at +the present day much of the work has been sketched rather than surveyed. +Even in the better surveyed portions reports come in as to dangers or +other matters not shown, and if of importance and the report appears to +be reliable these are sometimes at once put on the chart pending further +investigation, or in other cases an examination is first made. + +Shoals, rocks, and even islands have in numerous instances been shown on +the charts which no one has been able to find again, and many of them +after repeated searches have been removed. The same island or danger has +sometimes been charted in two or more different positions as reported at +various times. The treatment of such cases is one of the serious and +interesting problems of the chart maker. It is generally less harmful to +show a danger which does not exist than to omit one which does exist. On +the other hand a non-existing danger shown on a chart may be the cause +of actual expense and loss of time in compelling a vessel needlessly to +go out of its course. + +It is surprising to note with what lack of care and of sufficient +evidence reports of dangers at sea have sometimes been made, and how +incomplete are many of the reports even when the existence of the danger +is beyond question. It is unfortunately true that some of these reports +are the result of effort to escape blame for accident by throwing the +fault on the chart. Many such reports also result from various illusory +appearances. A large tree covered with weeds, an overturned iceberg +strewn with earth and stones, a floating ice-pan covered with earth, the +swollen carcass of a dead whale, a whale with clinging barnacles and +seaweed, reflections from the clouds, marine animalculae, vegetable +growth, scum, floating volcanic matter, and partially submerged wrecks +covered with barnacles, have been mistaken for islands, shoals, or +reefs. A school of jumping fish has given the appearance of breakers or +caused a sound like surf, and tide rips have been mistaken for breakers. +Raper very properly calls attention to the obligation upon every seaman +of carefully investigating doubtful cases and making reliable reports. +"Of the dangers to which navigation is exposed none is more formidable +than a reef or a shoal in the open sea; not only from the almost certain +fate of the ship and her crew that have the misfortune to strike upon +it, but also from the anxiety with which the navigation of all vessels, +within even a long distance, must be conducted, on account of the +uncertainty to which their own reckonings are ever open. No commander of +a vessel, therefore, who might meet unexpectedly with any such danger, +could be excused, except by urgent circumstances, from taking the +necessary steps both for ascertaining its true position, and for giving +a description as complete as a prudent regard to his own safety +allowed." + +As to the older doubtful dangers now shown on the oceanic charts, it is +estimated that the positions may be considered as uncertain by 10 miles +in latitude and 30 miles in longitude, and areas of this extent must be +searched to determine definitely the question of their existence. + +The following are interesting or typical cases of reported dangers: + +The master of an Italian bark in September, 1874, reported sighting a +large rock in latitude 40 deg. N. and longitude 62 deg. 18' W. Fortunately for +the charts there were two independent reports from other vessels in the +same month of sighting a partially submerged wreck in this vicinity. + +The Spanish steamer _Carmen_ was wrecked in 1891 by running on a rock +off the southwest coast of Leyte; the rock was reported to lie one mile +off shore, a dangerous position for vessels using Canigao Channel. A +survey made in 1903 showed 58 feet of water in this location, and +that Carmen Rock on which the vessel struck was really within one-fourth +mile of the beach. The rock had, however, for twelve years been shown on +the charts in a position which made it an obstruction to navigation. + +The ship _Minerva_ in 1834 was reported to have struck a rock near the +middle of the broad entrance to Balayan Bay; the fact that this occurred +at 2 A.M. indicated a very doubtful position, but it was stated that an +American ship had previously been wrecked on the same rock. It +consequently appeared as a danger on the charts for seventy-one years, +when a survey showed no depth of less than 190 fathoms in this vicinity, +and it was removed from the charts. + +A British steamer was wrecked in San Bernardino Strait in 1905; the +master reported that he was in a position where the chart showed 51 +fathoms, and that he was 1-1/2 miles distant from Calantas Rock, and on +these grounds the finding of the official inquiry was that "no blame can +be attached to the master, officers, or any of the crew for the +casualty." Very shortly after the disaster, the surveying steamer +_Pathfinder_ definitely located the wreck and made a survey of the +vicinity. The previous chart of Calantas Reef was found to be fairly +correct, and the stranding was determined to have occurred well within +this reef in a position where the chart showed soundings of 3-3/4 to +4-3/4 fathoms, and 1/2 mile from Calantas Rock, which rises 5 feet above +high water. + +A transport entering San Bernardino Strait a few years ago ran on a rock +and was damaged; the position was reported as about two miles southeast +of San Bernardino Island and near the middle of the passage. The rock +was not put on the charts, as prompt investigation showed 50 fathoms of +water in this vicinity, and that in all probability the transport +actually touched a small reef making out from the island. + +The master of the brig _Helen_ reported that his vessel was wrecked on a +reef lying six miles from Rockall. When surveyed Helen Reef was found to +be about one-third this distance from Rockall. + +An island has been reported in eight different positions, ranging in +latitude from 30 deg. 29' to 30 deg. 42' N. and in longitude from 139 deg. 37' to +140 deg. 38' E. + +There have been a number of reports of islands in the area from latitude +40 deg. 00' to 40 deg. 30' N. and longitude 150 deg. 30' to 151 deg. 00' W. The master +of the bark _Washington_ reported in 1867: "On my passage from the +Sandwich Islands to the northwest coast of the United States, when in +latitude 40 deg. 00' N., in a dense fog, I perceived the sea to be +discolored. Soundings at first gave great depths, but diminished +gradually to 9 fathoms, when through the mist an island was seen, along +which I sailed 40 miles. It was covered with birds, and the sea swarmed +with seal and sea elephants." A United States vessel searched in +this vicinity without seeing any indication of land, and obtained +soundings of 2600 fathoms. A British ship in 1858 searched for fourteen +days over this area without finding anything. Searches were also made in +1860 and 1867 without success, and the present charts show no islands in +this part of the Pacific. + +In a number of cases erroneous positions have been due simply to +blunders. Thus Lots Wife, first seen by Captain Meares in 1788, was +shown on his chart in latitude 29 deg. 50' N., longitude 156 deg. 00' E., and +stated in his book to be in latitude 29 deg. 50' N. and longitude 142 deg. 23' +E. Massachusetts Island by one report was in longitude 177 deg. 05' E. and +by another in 167 deg. 05' E. The apparent blunder of 10 deg. is now immaterial, +as the island has disappeared from the charts altogether. The Knox +Islands were placed by the Wilkes Exploring Expedition in latitude 5 deg. +59' 15'' N., longitude 172 deg. 02' 33'' E. The old British charts showed +islands of this name also in latitude 5 deg. 59' N., longitude 172 deg. 03' W., +the longitude being doubtless transposed. In the case of Starbuck +Island, discovered south of the equator, the latitude was apparently +transposed, as on old charts it was also shown in the position, latitude +5 deg. 40' N., longitude 156 deg. 55' W. + +A pinnacle rock can sometimes be located only with great difficulty even +when known to exist. Rodger Rock, on which the bark _Ellen_ struck and +was damaged, lies in latitude 0 deg. 41' 15'' N. and longitude 107 deg. 31' E. +It has but three feet over it at low tide. The British surveying ship +_Rifleman_ searched four days before finding it, although the plotted +tracks showed that she and her boats had passed very close to it. This +indicates that great caution must be used in removing a reported danger +from the charts. + +The old charts of the Atlantic indicated a danger 30 to 45 miles to the +southwest of Cape St. Vincent. This danger was omitted from the charts +about 1786 owing to lack of confirmation. Later, in 1813 and 1821, it +was reported that vessels were lost or damaged by striking this rock. +Soundings of over a thousand fathoms are now shown on the chart in this +vicinity and the rock no longer appears. + +A comparison of a Pacific Ocean chart of about forty years ago with one +of the present time (Fig. 19) illustrates in a striking manner how many +doubtful dangers, or vigias, have gotten on the charts and how after +laborious search many of them have now been removed. This condition was +especially true of the Pacific, owing to the numerous reports of an +indefinite nature from whaling ships, among whose captains there was a +saying "that they do not care where their ship is, so long as there are +plenty of whales in sight." + +[Illustration: FIG. 19. PORTION OF CHARTS OF 1869 AND 1903, OF THE +PACIFIC OCEAN WEST OF THE HAWAIIAN ISLANDS, TO ILLUSTRATE THE REMOVAL OF +DOUBTFUL DANGERS.] + +[Illustration: FIG. 20. PORTION OF CHART OF PONCE HARBOR, SCALE 1-20000, +TO SHOW SELECTION OF SOUNDINGS FROM ORIGINAL SURVEY GIVEN BELOW.] + +[Illustration: FIG. 21. HYDROGRAPHIC SURVEY OF SAME PORTION OF PONCE +HARBOR, REDUCED TO ONE-HALF SCALE OF ORIGINAL SHEET.] + + + + +PREPARATION OF INFORMATION FOR CHARTS. + + +#Chart schemes.# Before commencing the preparation of a chart it is +necessary to arrange a definite scheme for it, and the usefulness of the +chart will depend materially on this preliminary plan, in which must be +outlined its scale, size, limits, and features to be represented. New +charts have sometimes been prepared simply to fit the surveys as they +progressed or to fill immediate or local requirements. It is, however, +desirable that general plans for series or groups of charts be made, and +with changing needs, information, and conditions it is sometimes +necessary that existing schemes be modified. + +#Compilation of information.# Considerable work must usually be done to +get the field records in shape for the published chart. The soundings +must be plotted and the characteristic depths selected. Only a part of +the soundings that are made can be shown on the original sheet and only +a small part of these are used on the final chart. A selection is made +showing the least soundings on shoals and bars, the channel depths, and +the characteristic soundings in anchorages and other areas. The original +surveys are generally made on a considerably larger scale than that on +which the chart is published, in order that the soundings may be more +thoroughly plotted. The sheets must then be reduced to the scale of +publication, and this can conveniently be done by means of photography +or with a pantograph. + +The best judgment is required in selecting the important features +to be shown on the chart and omitting the less important and not +essential features which might tend to obscure the others. In charts of +new regions where complete surveys are lacking, care must be exercised +in weighing, combining, and adjusting information from various sources +and which is, perhaps, more or less conflicting. + +#Projections.# The surface of the earth being curved, there is no +possible system of projection by which it can be represented on a flat +sheet of paper in an ideally satisfactory way. Numerous methods of +projecting the earth's surface upon a plane have been proposed and many +of them are actually used for various purposes. In general each +projection has qualities which are valuable for certain uses, and +deficiencies which make it less valuable in other ways. Only four of the +different projections need be mentioned here as of special interest in +chart construction. + +#Mercator projection.# This is a rectangular projection in which the +meridians are straight lines spaced at equal intervals and the parallels +are straight lines so spaced as to satisfy the condition that a rhumb +line, or line on the earth cutting successive meridians at the same +angle, shall appear on the developed projection as a straight line +preserving the same angle with respect to the meridians. + +This projection may be considered as the unrolling upon a plane of the +surface of a cylinder tangent to the earth along the equator, and upon +which the various features of the earth's surface have been projected in +such manner as to satisfy the above requirement. + +On this projection there is a constant distance between the meridians, +whereas on the earth they actually converge toward the poles. The +distance between the parallels increases in passing toward the poles, +approximately in the proportion of the secant of the latitude. For each +small portion of the map the relative proportions are maintained as on +the earth. + +Some characteristics of the mercator projection are these: The meridians +and parallels are all straight lines and perpendicular to each other; +there is no convergence of the meridians; the minute of longitude is a +constant distance on the map; the minute of latitude increases in length +from the equator toward the poles but locally retains its true +proportion to the minute of longitude; areas and distances increase in +scale with the latitude so that a given scale is strictly correct only +for one latitude; great circles and consequently lines of sight are +curved lines excepting the meridians and the equator; rhumb lines or +lines having a constant angle with the meridians are straight, and for +the same angle are parallel in all parts of the chart. These qualities +are all rigid and the projection can therefore be used for all areas, +small or large, up to the extent of the earth's surface, except that it +cannot be extended to the poles, as there the length of the minute of +latitude would become infinite. + +An interesting fact regarding a rhumb line oblique to the meridians is +that it is a spiral continually approaching but never reaching the pole; +this spiral makes an infinite number of revolutions around the pole, and +yet it has a finite length for the reason that the length of each +revolution diminishes as the number of revolutions increases. + +[Illustration: FIG. 22. MERCATOR PROJECTION OF NORTH PACIFIC OCEAN, +SHOWING GREAT CIRCLE ROUTES YOKOHAMA TO PUGET SOUND, AND YOKOHAMA TO +HONOLULU AND THENCE TO SAN FRANCISCO.] + +The mercator projection has been extensively used for nautical charts, +for which it presents important mechanical advantages, in that adjacent +charts can be joined on all their edges while still oriented with the +meridian; all charts are similar; the border may be conveniently +subdivided, giving a longitude scale applicable to any part of the +chart, but a latitude scale that may be used in the same latitude only; +courses are laid down as straight lines and can be transferred with +parallel rulers from one part of the chart to another without error. On +a mercator chart an island in latitude 60 deg. would appear four times as +large as an island of the same actual area at the equator, but this +distortion of areas, while it gives erroneous impressions on charts of +great extent in latitude, does not seriously affect the use of the chart +for nautical purposes. Areas may also be correctly measured on a +mercator map by taking each projection quadrilateral separately, +subdividing it if necessary, and using the published tables of areas of +quadrilaterals in different latitudes. Although distance scales vary +with the latitude, distances can be taken from this chart with fair +correctness by the use of the latitude border scale for the middle +latitude, subdividing the total distance if there is much range of +latitude. The inability to take off the great circle or shortest course +directly from the mercator chart is from a navigational point of view a +defect, but the most convenient solution for this appears to be the +supplementary use of a gnomonic chart as will be described. The fact +that lines of sight are not straight lines on this projection is another +defect, as by the plotting of bearings and angles on approaching the +land the positions of vessels are located on the chart; fortunately, +however, the error due to this cause usually falls within the other +uncertainties involved in locating a ship; if need be it would be +practicable to allow for this curvature. In the polar regions, however, +the faults of the mercator projection become so much exaggerated that it +is not used for navigational purposes, but because of the absence of +commercial navigation there this is a minor matter in the general +question of chart projection. For the plotting of original surveys the +mercator projection is not suited and is not used, for the reasons above +mentioned. + +[Illustration: FIG. 23. POLYCONIC PROJECTION OF PORTION OF NORTH PACIFIC +OCEAN.] + +Tables of "meridional parts" are published which give the distance in +terms of minutes of longitude from the equator to the various parallels; +with these tables a mercator projection may readily be constructed. + +Airy proposed a graphical method of sweeping the arc of a great circle +on to a mercator chart, and tables are published for this purpose. The +method is only approximate and is limited in application, and the +supplementary use of a gnomonic chart would appear to be preferable. + +#Polyconic projection.# In plotting the original surveys it is essential +that a projection be used which will for the area included on a survey +sheet show the points in their correct relation both as to direction and +distance. These conditions are substantially fulfilled by several +projections, of which the polyconic is used in the United States. If a +hollow cone were placed so that it would either be tangent to the +earth's surface along one of the parallels of latitude or cut it along +two parallels, and the points projected on to this cone, and the cone +then unrolled and laid out flat, the result would be a conical +projection, of which there are several variations. If successive tangent +cones be used and each parallel of latitude be developed as the +circumference of the base of a right cone tangent to the spheroid along +that parallel, the result is the polyconic projection, which has been +used for field sheets and for the large scale charts, as well as for the +topographic maps of the United States. This projection has valuable +qualities for moderate areas of the earth's surface, within which the +scale is approximately uniform, areas retain nearly their true +proportions, and great circles and consequently all bearings and +directions are approximately straight lines. The parallels of latitude +are arcs of circles with radiuses increasing as we recede from the pole; +therefore they are not truly parallel and the length of the degree of +latitude increases either side from the central meridian. The meridians +converge toward the poles and become slightly curved as we recede from +the central one; the longitude scale is everywhere correct, but the +latitude scale is strictly correct only on the central meridian. The +angles of intersection of parallels and meridians are right angles or +nearly so. The polyconic projection is not used for very extensive areas +of the earth's surface, as for instance a hemisphere. + +[Illustration: FIG. 24. GNOMONIC CHART OF NORTH PACIFIC OCEAN, SHOWING +GREAT CIRCLE ROUTES YOKOHAMA TO PUGET SOUND, AND YOKOHAMA TO HONOLULU +AND THENCE TO SAN FRANCISCO.] + +#Gnomonic projection.# In this projection the eye is assumed to be at +the center of the earth and the features are projected upon a plane +tangent to some point on the earth's surface. It is practicable to use +this projection for oceanic areas, and it has the very important quality +that every straight line on it represents a great circle of the earth. +To obtain the great circle or shortest course between two points it is +therefore only necessary to draw a straight line between the points on a +gnomonic chart. Because of the great distortion near the edges this +projection is not otherwise adapted to navigational use, and it is +employed only to mark out the general course, and sufficient points are +then transferred to a mercator chart. The gnomonic chart is therefore +useful in supplementing the mercator chart, supplying its deficiencies +as to convenience in marking out great circle courses. The great circle +course can be derived not only more easily and quickly from the gnomonic +chart than by computation, but the chart is also to be preferred because +the course marked out on it will show at once if any obstruction, as an +island or danger, is met or too high a latitude is reached. A modified +or composite course can readily be laid out on a gnomonic chart. + +[Illustration: FIG. 25. NORTH POLAR CHART ON ARBITRARY PROJECTION.] + +#Arbitrary projection.# The few charts published of the polar regions +are sometimes on an arbitrary projection, in which the meridians are +straight lines radiating from the pole and the parallels are equidistant +circles with the pole as center. The latitude scale is uniform. At some +distance from the pole the longitude scale becomes very much distorted, +but the projection is a practicable and convenient one for the immediate +polar regions. Gnomonic and conical projections are also used for the +polar charts, differing little from the foregoing for moderate areas. + +#Scales.# Charts are published on a variety of scales to suit different +needs of navigation, and the usual classification depends on scale. In +addition to the ocean charts covering a single ocean in either one or +several sheets and intended for navigation on the high seas, +there are for our Atlantic coast the following series: + +Sailing charts, scale about 1/1200000, for general coastwise navigation. + +General coast charts, scale 1/400000, for local coastwise navigation. + +Coast charts, scale 1/80000, for approaching the coast at any point and +for inside passages. + +Harbor and channel charts, of various large scales from 1/5000 to +1/60000, for entering harbors and rivers and passing through channels. + +The expression of scales by miles to the inch or inches to the mile is +the more familiar. The expression of scale in the manner used by the +Coast Survey and by most of the European countries, by standard +fractions as 1/80000, meaning that any distance on the chart is 1/80000 +of the actual distance on the earth, has some advantages. For instance, +the relation of these fractions gives at a glance the relation of the +scales of the charts. Thus a 1/80000 chart is on a scale five times as +large as a 1/400000 chart. + +For the more important harbors charts have been published on several +different scales to meet various needs. Thus New York Harbor is shown on +charts of scales of 1/10000, 1/40000, 1/80000, 1/200000, 1/400000 and +1/1200000, each of course including a different area. + +[Illustration: FIG. 26. NEW YORK HARBOR, PORTIONS OF CHARTS ON FOUR +DIFFERENT SCALES.] + +The selection of suitable publication scales is of prime importance; a +large scale permits of greater clearness and of showing more detail, but +on the other hand restricts the area and the points that can be shown on +a single sheet, or else makes a chart of excessive dimensions. In +general in chart preparation the scale should be restricted to the +minimum that can be used to fulfill the particular object and clearly +represent what is desired. A chart of very large scale is not convenient +for plotting, and a moving vessel may pass quickly beyond it or into +range of objects beyond the limits of the chart. + + + + +PUBLICATION OF CHARTS. + + +#Methods of publication.# An ideal process of publication for nautical +charts would include the following features; rapidity in getting out new +charts, facility in reprinting and correcting existing charts, clearness +and sharpness of print, durability of paper and print, and correctness +of scale. It is difficult to fulfill all these requirements by any +method as yet developed. In the Coast and Geodetic Survey several +different processes are in use at present; charts are engraved on copper +and printed directly from the copper plate, or they are transferred from +the copper plate to stone and printed from the stone, or a finished +drawing is made and transferred to stone by photolithography and printed +from the stone, or an etching is made on copper from a finished drawing +and printed from a transfer to stone. Charts in other countries are in +large part printed from engraved plates, excepting some preliminary +charts by lithography. + +[Illustration: FIG. 27. ENGRAVING A CHART ON A COPPER PLATE.] + +[Illustration: FIG. 28. ENGRAVING SOUNDINGS ON A COPPER PLATE WITH A +MACHINE.] + +#Copper plate engraving and printing# have long been used in chart +preparation. A drawing is prepared as a guide for the engraver; this +must be correct as to all information to be shown but need not be a +finished drawing. A true projection is ruled upon a copper plate. By +photography a matrix is made from the drawing and a wax impression taken +from this matrix. This is then laid down on the copper to fit the +projection, and the impression is chemically fixed on to the copper. The +work thus marked out is engraved by hand or by machine. A high degree of +skill is required in the accuracy and finish necessary for chart +engraving. Machines have been invented in recent years which can be used +for portions of the work on copper plates, as for instance for cutting +the sounding figures, the bottom characteristics, the border and +projection lines, border divisions, compasses, line ruling, and stipple +ruling. Stamps and dies have been successfully used for some symbols and +notes, and roulettes for shading. By means of these various machines, +many of which are American inventions, the process of chart publication +from plates has been materially facilitated. + +[Illustration: FIG. 29. ELECTROTYPING PLANT FOR ELECTROTYPING CHART +PLATES.] + +When the plate is completed an alto, or raised copy, is made by +depositing copper on to it in an electrotype vat, and from this alto +another basso or sunken copy is made by the same process. This latter +basso is used in printing. A copper plate may be used for about 3000 +impressions, after which it may become too much worn for satisfactory +chart printing. By printing from a duplicate basso the original plate is +preserved and additional copies can be made when needed. The use of the +alto also greatly facilitates matters when a considerable correction to +the chart is required. All the portions of the chart to be changed can +be scraped off the alto, and when a new basso is electrotyped from this +scraped alto all such areas will of course appear as smooth copper, on +which the new work can be engraved. Numerous small corrections are +called for on charts, and on copper plates where these are to replace +old work the latter is removed either by hammering up the back of the +plate or by scraping its face. + +Printing directly from plates is a laborious process. After the press +bed has been carefully padded to take up inequalities in the plate, the +surface of the latter is covered with ink and then carefully wiped off +by hand, leaving the ink only in the engraved lines. The paper, first +dampened, is laid on the plate, and passes with it beneath the cylinder +of the press under considerable pressure. The prints are calendered by +being placed in a hydraulic press under 600 tons pressure. The charts +are beautifully clear and sharp, not equalled by other methods of +printing. Owing to the wetting and drying of the paper, the finished +print is, however, quite appreciably smaller in scale than the plate, +and the shrinkage is greater in one direction than in the other. The +average day's work for one press and two men is 75 prints. This is small +compared with the output practicable with lithographic presses. On the +other hand a plate can be prepared for printing more readily than a +lithographic stone. For small editions the plate printing compares well +in economy with lithographic printing, and the plate can also be printed +on short notice. Because of changes in aids to navigation and other +corrections, it is usually desirable to print at one time only a +sufficient number of copies of a chart to meet current demands, and not +to carry a large stock on hand. + +[Illustration: FIG. 30. PRINTING CHARTS FROM COPPER PLATES; FINAL +CLEANING OF THE PLATE BY HAND; PLATE PRESS ON THE LEFT.] + +The copper plates, bassos, and altos make a very convenient and enduring +means of preserving the chart ready for printing or for further +correction. A large number of plates can be placed in a small space, and +if properly cared for they may be stored indefinitely without +deterioration. + +With plate printing it is not practicable to print more than one +impression on the chart or to use more than one color, and plate-printed +charts are therefore in black only. + +[Illustration: FIG. 31. LITHOGRAPHING PRESSES FOR PRINTING CHARTS; +LITHOGRAPH STONE ON TRANSFER PRESS.] + +#Engraving on stone.# On the United States Lake Survey the charts are +first engraved on stone, and by a special process the work is then +transferred to small copper plates, which are preserved. The final +publication is by lithography, transferring again from the plates to +stone. + +#Photolithography# is a quick method of publishing a chart. It would be +practicable by this means to reproduce the original survey sheets, but +ordinarily these are not suitable as to scale and legibility, and it is +necessary to make a new drawing, usually on tracing vellum. This is +photographed on to glass plates, on the scale of the proposed chart. +From these glass negatives positive prints are made on sensitized +lithographic paper. These prints are fitted together and then inked, +taking the ink only where the lines appear. This transfer print is then +laid face down on the lithographic stone and run through a press under +pressure, the stone absorbing the ink from the paper. The stone is then +treated so that the inked portion remains slightly raised, and from this +stone an indefinite number of charts can be printed in a lithographic +press at the rate of 1000 an hour. The paper is not moistened, and +consequently there is little distortion or change of scale in prints +from stone. If desired to shade the land or use another color for any +other purpose, additional impressions can be made on the same charts +from other stones. Because of the bulk of the stones, work cannot +ordinarily be retained on them, but the chart is cleaned off and the +stones repeatedly used until worn thin. The original drawing as well as +the negatives is preserved, from which the chart can again be published. +For republication, the process is, however, not entirely satisfactory; +the negatives are not always permanent, the work must again be assembled +and transferred to the stone, changes or corrections are not very +conveniently made on either drawing or negative, and after repeated +changes the drawing becomes difficult to use in photolithography. +Whether the charts are actually printed from copper or stone, there are +decided advantages therefore in the matter of correction work and future +editions in having the charts engraved on copper. On the other hand, the +advantages of the photolithographic process are the ability to publish +new drawings promptly, to use more than one shade on a chart, to obtain +prints with little change of scale or distortion, and to print large +editions rapidly. + +#Lithographic printing by transfer from engraved plates.# An impression +on transfer paper may be taken from an engraved plate and this laid down +on the stone in a manner similar to that used in laying down the prints +from the glass negatives in photolithography. Prints are then made from +the stone the same as in photolithography, but with superior results as +to clearness. This general process is extensively used in both map and +chart publishing in this country, as it combines the advantages of the +plate in preservation of the chart record and facility of correction, +and the advantages of the lithographic printing in less distortion of +the printed chart, ability to print more than one shade, and facility +for large editions. As the transfer from the plate can be readily made +it is also better applicable to small editions than is photolithography. +It is, however, not as convenient in the latter respect as plate +printing, and it does not give a resulting impression equal in clearness +or durability to the impression directly from the plate. + +#Etching on copper# for chart publication has been recently developed in +the Coast and Geodetic Survey. A finished tracing is made, the surface +of a smooth copper plate is sensitized, and by exposure to the sun a +print is made on the sensitized surface. It is essential to use an +air-exhausted printing frame so as to get good contact between the +vellum and the plate. The work is then etched into the copper and the +plate cleaned and touched up, after which it may be used the same as a +hand-engraved plate, either for transfer to stone or direct plate +printing. The expense and time required in the etching process are much +less than for hand engraving. The process has been successfully used for +a number of harbor charts. The etching of course will be of the same +scale as the vellum at the time of the print, and vellum varies somewhat +in scale with weather conditions and age. Unless overcome by the +substitution of some more invariable material in place of vellum, this +might be an obstacle to the use of the process for general charts where +a true scale on the copper plate is desirable because of future work to +be done on the plate. It must also be taken into account that the +etching requires a finished tracing in ink, which is not essential for +the hand engraver; if, however, the chart is first published by +photolithography, as is the usual practice in the Coast and Geodetic +Survey, the same tracing is used for both processes. + +#Distribution of charts.# Charts published by the government are sold to +the public at a small price, estimated to cover the cost of paper and +printing. The charts may be obtained direct from the publishing office +or from the chart agents who are to be found in all the principal +seaports. Catalogues are published from time to time giving complete +lists of the current charts and the main facts regarding them. Index +maps show graphically the area covered by each chart. The notices to +mariners contain announcement of new charts or new editions published +and of charts or editions cancelled, as well as of all corrections. + + + + +CORRECTION OF CHARTS. + + +#Need for revision.# The making of the survey and the printing of the +chart do not complete the problem of the chart maker. Both nature and +man are constantly changing the facts the representation of which has +been attempted on the charts, and also the needs of man are always +varying. The original surveys are made to meet the reasonable +requirements of the time, but breakwaters and jetties are built, and +channels and harbors dredged and otherwise improved, and cities built, +and new paths of commerce are opened which bring vessels into waters +previously thought of minor importance. + +With the increase of commerce and speed of vessels more direct routes +are demanded for reasons of economy. Inside routes not originally used +are sometimes developed for defensive reasons. The average draft of the +larger vessels has also increased remarkably since the modern +hydrographic surveys were commenced, and surveys once made to insure +safety for the deepest vessels of that time are now not adequate. The +average loaded draft of the 20 largest steamships of the world has +increased as follows: 1848, 19 feet; 1873, 24 feet; 1898, 29 feet; +1903, 32 feet. The average length of these vessels was 230 feet in 1848, +390 feet in 1873, 541 feet in 1898, and 640 feet in 1903. The number of +vessels drawing as much as 26-1/4 feet rose from 36 in 1902 to 185 in +1904. In 1906 there were 17 vessels afloat, drawing 32 feet and upwards. +There are now two steamers on the Atlantic 790 feet long, 88 feet beam, +and 37-1/2 feet draft when fully loaded, and larger vessels are already +planned. + +Great natural agencies are also constantly at work effecting changes in +features shown on the charts. The action of currents and waves is +continually cutting away or building the shore, particularly on sandy +coasts exposed to storms. When surveyed in 1849 Fishing Point on the +east coast of Maryland was but a bend in the shore line. By 1887 it had +built out about two miles in a southerly direction, and in 1902 about +two-thirds of a mile further, curving to the westward. Altogether in +about half a century this tongue of land has grown out nearly three +miles. + +Rivers are bearing vast quantities of sediment and depositing these near +their mouths, pushing out the coast line and filling in the bottom. The +main mouths of the Mississippi are advancing into the Gulf, but at a +comparatively slow rate. A break from the main river at Cubit's Gap +just above the head of the passes, however, has done an enormous amount +of land making, filling in an area of about 50 square miles between 1852 +and 1905. + +[Illustration: FIG. 32. FISHING POINT, MARYLAND, FROM SURVEYS OF 1849 +AND 1902, ILLUSTRATING BUILDING OUT OF A POINT ON THE COAST.] + +[Illustration: FIG. 33. GROWTH OF LAND AT CUBITS GAP, MISSISSIPPI DELTA, +FROM 1852 to 1905.] + +[Illustration: FIG. 34. COLUMBIA RIVER ENTRANCE, SHOWING MOVEMENT OF +SAND ISLAND, SURVEYS OF 1851, 1870 AND 1905.] + +The mouth of the Columbia River in Oregon shows an interesting example +of the movement of an island. The chart of 1851 shows the center of Sand +Island 3-1/4 miles southeast of Cape Disappointment, the chart of 1870 +shows it 2-3/4 miles southeast, and the chart of 1905 shows it 1-1/4 +miles easterly. This island has thus moved 2 miles northwesterly +directly across the middle of the river entrance, closing up the former +north channel. The southern point of the entrance, Clatsop Spit, has +built out about the same distance. + +[Illustration: FIG. 35. CHANGES IN HAULOVER BREAK, NANTUCKET ISLAND, +1890 TO 1903.] + +[Illustration: FIG. 36. MAPS OF BOGOSLOF ISLAND, 1895 AND 1907, SHOWING +CHANGES DUE TO VOLCANIC ACTION.] + +[Illustration: + + _Photo by U. S. R. C. Service._ + +FIG. 37. BOGOSLOF VOLCANO, BERING SEA.] + +Volcanic action in well authenticated cases has caused islands to rise +or disappear. In the present location of Bogoslof Island in Bering Sea +the early voyagers described a "sail rock." In this position in 1796 +there arose a high island. In 1883 another island appeared near it. In +1906 a high cone arose between the two, and a continuous island was +formed over 1-1/2 miles long and 500 feet high. The latest report +(September, 1907) was that this central peak had suddenly collapsed and +disappeared. Bogoslof is an active volcano, and the main changes have +been the result of violent volcanic action. The history of this island +for over a century past forms a remarkable record of violent +transformations in the sea. + +Earthquakes sometimes cause sudden displacements, horizontal or +vertical, of sufficient amount to affect the information shown on the +charts. A careful investigation of the effects of the earthquake in +Yakutat Bay, Alaska, in September, 1899, showed that the shore was +raised in some parts with a maximum uplift of 47 feet and depressed in +other parts, and that at least two reefs and four islets were raised in +the water area where none appeared before. Undoubtedly there were +changes in the water depths, but definite information is lacking because +there had been no previous hydrographic survey. The San Francisco +earthquake of 1906 caused little vertical displacement, but there were +horizontal changes of relative position as much as 16 feet; so far as +known this earthquake did not affect the practical accuracy of the +charts. Related to earthquake phenomena are the gradual coast movements +of elevation or subsidence which are taking place but at so slow a rate +as not to sensibly affect the charts in ordinary intervals of time. + +Another agency at work is the coral polyp on the coral reefs; although +the rate of growth appears to be very slow, the resulting reefs and keys +are an important feature in tropical seas. + +Practically all of the land features shown on charts are likewise +subject to changes, the more rapid of which are mainly due to the works +of man. + +The changes of channels and of commercial needs cause many alterations +to be made from time to time in the lights and buoys which are shown on +the charts. + +#Methods of correction.# The problem of keeping a chart sufficiently up +to date is one of much practical importance and one which must be taken +into account in planning what should be shown on the chart in the first +place so as to bring it within the range of practicable revision. + +Certain features are corrected at once on the charts as soon as the +information is received, such as dangers reported, and changes in lights +and buoys. Where harbor works are in progress the periodic surveys made +in this country by the Corps of Engineers furnish data which are applied +promptly to the charts. Reported dangers in channels and bars are +investigated by special surveys and the information is put on the +charts. Examinations are made from time to time for the revision of the +features along the coast line. Complete resurveys have been made, at +long intervals, of some important portions of the coast where there has +been evidence of change, and these, when they become available, are +applied to the charts. All parts of the coast where the exposed portions +are not of very permanent material will require resurveys at intervals, +depending on their importance and the rate of change. + +Notwithstanding the great progress made in hydrographic surveys, a +considerable number of rocks and shoals dangerous to navigation and not +previously shown on the charts are reported, averaging nearly 400 each +year for the last six years, according to the British reports. Of the +367 reported in 1906, 11 were discovered by vessels striking them. + +Immediate information in the form of _Notices to Mariners_ is published, +of the more important corrections to charts which can be made by hand. +These corrections show what charts are affected, and give sufficient +data for plotting. + +In the case of extensive corrections or new surveys a new edition of the +chart is printed and all existing copies of the previous edition are +canceled. + +It is important that the user of the chart shall make certain that he +has the latest edition and that all corrections from its date of issue +have been applied from the _Notices to Mariners_. + +It is unfortunately true that owing to failure to take proper account of +the notices, or to economy, old editions or unconnected charts are +sometimes used, and in a number of cases the loss of vessels has been +directly due to this cause. Those responsible for the safe navigation of +vessels should insist that the latest editions of charts are provided +and that all charts to be used are inspected and corrected to date. + + + + +READING AND USING CHARTS. + + +#Reading charts.# A chart is a representation on paper of hydrographic +and topographic information by means of various conventional methods and +symbols. It is evidently important for those making use of charts to +understand the system and conventions used, and to be able to interpret +readily the various parts of the chart. The ability to read a chart must +include an understanding of all its features, such as scale, projection, +geographic position, directions, depths, plane of reference, aids to +navigation, tides, currents, elevations, topography, and date of survey +and publication. + +#Scale.# For American and British charts the scale is usually expressed +by the inches or fractions of an inch to the minute or degree of +latitude, or by the fractional proportion of a distance on the map to +the corresponding distance on the earth. These fractions are sometimes +stated on the British charts, and nearly always on those of the United +States Coast Survey. The chart catalogues give the scale in one or the +other form. A familiarity with the meaning of scales is of value in +selecting the most suitable chart, in judging of the relative uses of +charts, and in estimating distances. Where the fractional scales are +stated they furnish a simple means of comparing charts, as, for +instance, a chart on 1/50000 scale will show all distances just twice as +long as a chart on 1/100000 scale. + +The following are scale equivalents: + + Scale 1/10000 is equivalent to 7.30 inches to one nautical mile. + Scale 1/20000 is equivalent to 3.65 inches to one nautical mile. + Scale 1/40000 is equivalent to 1.82 inches to one nautical mile. + Scale 1/50000 is equivalent to 1.46 inches to one nautical mile. + Scale 1/80000 is equivalent to 0.91 inch to one nautical mile. + Scale 1/100000 is equivalent to 0.73 inch to one nautical mile. + Scale 1/200000 is equivalent to 0.36 inch to one nautical mile. + Scale 1/400000 is equivalent to 0.18 inch to one nautical mile. + Scale 1/1000000 is equivalent to 0.07 inch to one nautical mile. + Scale 1/1200000 is equivalent to 0.06 inch to one nautical mile. + +For use in measuring distances on large scale charts the length of one +or more nautical miles is usually drawn on the chart, and sometimes +scales are also given in other units. On British charts the nautical +mile scale is divided into tenths (that is, cables of 100 fathoms or 600 +feet length); on the American charts into quarters and eighths. Where +the scale covers more than one mile the fractional divisions are shown +only for the left-hand mile and the zero of the scale is placed between +this and the full mile scale, so that with dividers the full miles and +fraction may readily be taken off. The nautical mile in the United +States is taken to be the length of a minute of arc of a great circle on +a sphere whose surface equals that of the earth; this definition makes +the nautical mile equal 6080.27 feet. Lecky adopts 6080 feet as the +nautical mile. The length of the actual minute of latitude on the +earth's surface increases from 6046 feet at the equator to 6108 feet at +the poles, an increase of about one per cent. It is, however, this +somewhat variable unit of length which is ordinarily used in scaling +distances on the sailing charts. + +On small scale charts there is usually a border scale entirely around +the chart, conveniently subdivided; this serves the double purpose of +facilitating the plotting or reading of positions by latitude and +longitude and of furnishing a scale of minutes of latitude for use in +measuring distances. On a mercator chart this scale of course varies +with the latitude and it must be referred to in the mean latitude of the +distance to be measured. In general practice the minute of latitude is +taken as equal to the nautical mile. + +#Projection.# On only a few charts is there a statement of the +projection used. Practically all general sailing charts are on the +mercator projection, which can be readily recognized by the rectangular +network of meridians and parallels and the increase with latitude of the +distance between the parallels. On large scale local and harbor charts +the kind of projection used is not of importance to navigation, as for +such limited areas the difference between projections would not affect +the use of the chart. On certain small scale charts of the United States +Coast Survey which are on the polyconic projection this fact is stated +on the chart, and can also be readily recognized by the convergence of +the meridians and curvature of the parallels. Gnomonic charts intended +for taking off great circle courses are always described in their titles +and are also easily recognized by the increased scale and distortion +toward all the borders. Charts of the polar regions are published on +several different projections, which are distinguished from the mercator +by their circular or curved parallels. + +#Geographic position.# For large scale and harbor charts the latitude +and longitude of some point marked on the chart are sometimes stated on +the face of the chart. For others of these, however, and for smaller +scale and general charts, positions are obtained by reference to the +border scale. There is a latitude scale down either side of the chart, +and a longitude scale across the top and bottom. These scales are +conveniently subdivided into degrees, minutes, or fractions of a minute. +The minute is divided into tenths (6''), sixths (10''), quarters (15''), +or halves (30'') on various charts. + +#Directions# are indicated on charts both by the projection lines and by +compass roses. Nearly all charts are now oriented with the meridian, +that is, north is the top of the chart, and on a mercator chart the east +and west border lines are parallel with the meridians and the north and +south border lines with the parallels. Formerly many charts were not so +oriented. Some of these are still in use and can readily be recognized +by the diagonal or inclined direction of the projection lines with +respect to the border of the chart. Of course directions must not be +referred to the border lines of these diagonal charts, and scales along +such border lines must not be used. Directions with respect to true +north may always be referred to the projection lines of the chart, but +on a polyconic or polar chart a direction must not be carried so far +from any projection line as to introduce error on account of +convergence of the meridians. Compass roses are placed on charts to +facilitate the taking off or laying down of directions, though in some +respects their use is less accurate and convenient than the use of +protractors, referring to the projection lines. The British charts and +many of those of the United States Coast Survey have only magnetic +compasses, with degrees outside and points inside, the former graduated +to 90 deg.. These are engraved on the chart with the magnetic variation for +the date of publication, or for a few years in advance, and give the +annual change in the variation. Because of expense of engraving they can +be changed on the charts only at intervals of some years, and until this +is done allowance for the change in variation is to be made if +important. The German charts and those of the United States Hydrographic +Office now have a threefold compass, the outer one degrees true, the +middle degrees magnetic and the inner points magnetic; the degrees in +both cases are graduated to 360 deg., reading from north through east, +south, and west; thus northwest would be stated as 315 deg. instead of N. +45 deg. W. Small scale charts covering extensive areas have no magnetic +compasses. They sometimes have true compasses, and usually have the +isogonic lines, or lines of equal magnetic variation, marked on them, +from which the variation at any intermediate point can be estimated. + +#Depths.# The unit used for depths is always stated plainly on the +chart, and it is important to note this carefully, as the British, +American, and Japanese charts use fathoms for some charts and feet for +others, and most other countries use meters. Some of the earlier charts +of the United States coast have the depths inside of the 18-foot curve +in feet and outside of that curve in fathoms. + +Depth curves are shown on charts in order to bring clearly to the eye +the different depth areas and the limits for navigation of vessels of +various drafts. The shoaler areas are usually indicated by sanding the +outer limit or the entire area within the depth curve. For the curves +of greater depths various standard symbols are used which vary slightly +in the different series but which may readily be recognized by the +soundings on either side of them. On the British charts the 1 and 3 +fathom curves are usually indicated by sanding the outer edge of the +areas of these depths respectively; beyond these the standard curves +shown on these charts are the 5, 10, 20, and 100 fathom curves. Similar +curves are used on the United States charts. The German charts show the +2, 4, 6, 10, and 20 meter and various deeper curves, and the French the +2, 5, 10, and 20 meter and deeper curves. On the United States Lake +Survey charts the areas included within the 6, 12, and 18 foot curves +are shaded with a blue tint, heavy along the outer edge, which brings +out strongly the shoal areas. + +Depth curves if clearly shown are a great aid in interpreting the +hydrography and making plain the shoals and passages. The system of +curves should always be understood when using a chart, and it may +sometimes aid the navigator to trace out with a pencil an additional +curve, if needed, beyond the draft of his vessel. The abbreviations used +for the bottom characteristics are explained either on the chart or on +the sheet of chart symbols, and give information which is useful in +anchoring, and may be helpful in identifying a position by soundings. +When a sounding is made without the lead reaching bottom, the depth +obtained is sometimes shown on the chart by a short line and zero above +the figure, indicating that at the depth stated, bottom was not obtained +(no bottom). There are a few important symbols shown in the water area +of charts. The sunken rock symbol indicates a dangerous area, or a +danger having a moderate depth of water over it, or a rock the least +water over which is not known; ordinarily on the United States charts +the least depth will be stated when known, and the symbol omitted. The +rock awash symbol indicates a rock awash at some stage of the tide, +unless more definitely stated. The position of a wreck is indicated by a +special symbol. P. D. (position doubtful) and E. D. (existence doubtful) +are placed after soundings or rocks or other features which depend on +some doubtful report not yet verified. + +The following are the relations between depth units found on various +charts: + + 1 meter = 3.281 English feet = 0.547 English fathoms. + 1 sajene (Russian) = 7 English feet = 1.167 English fathoms. + 1 braza (old Spanish) = 5.484 English feet = 0.914 English fathom. + 1.829 meters = 6 English feet = 1.000 English fathom. + +#Aids to navigation.# Each series of charts has a definite system of +representing the aids to navigation; these are similar in principle but +differ as to detail. The characteristics of the lights, light-vessels, +buoys, and beacons are usually explained by abbreviations placed by the +side of each, and the entire system of representation is given on the +explanatory sheet for the charts. Various methods of coloring lights and +sectors and buoys are in use on different charts. It is evidently of +importance that the user of the chart should readily understand the +significance of the navigational aids as shown. For details regarding +lights it is of course desirable to refer to the light lists; for the +coasts of the United States detailed buoy lists are also published. +Range and channel lines when shown are represented by distinctive +symbols with bearings indicated. Danger ranges for the avoidance of +shoals are sometimes shown. On the British charts bearings as stated on +range and channel lines are magnetic; the custom varies on other charts +and must be carefully noted in each case. + +#Plane of reference.# The soundings given on the chart express the depth +of water when the tide is at the height adopted for the plane of +reference; this same plane is used in the tide tables, which thus will +indicate the amount to be added to the soundings when the tide is above +the plane, or to be subtracted when it is below. In order to be on the +safe side the plane of reference adopted is always some low stage of the +tide, so that there is usually more water than shown on the chart. + +On the British and German charts the soundings are reduced to the mean +low water of ordinary spring tides, unless otherwise stated. On the +charts of the Coast and Geodetic Survey the following are the planes of +reference: for the Atlantic and Gulf coasts, the mean of the low +waters; for the Pacific coast, Alaska, and the Philippines, the mean of +the lower low waters, except for Puget Sound and Wrangell Narrows, where +planes two and three feet lower respectively have been adopted. +According to the Tide Tables for 1908, at New York (Sandy Hook) the tide +will fall below the plane of reference on 135 days during the year, but +the extreme low tide will be only one foot below the plane. At Portland, +Maine, in 1908, the extreme low water is 2.1 feet below the plane, and +at San Francisco 1.5 feet. Of course when the tide is below the plane of +reference the amount must be subtracted from the depths shown on the +chart. + +Strong winds and unusual barometric pressure may have a marked effect on +the height of tide, so that it may differ appreciably from the predicted +height, which is of course based on normal conditions. At Baltimore and +at Willets Point observation shows that a heavy wind may reduce the tide +four feet below the predicted heights. + +#Tides.# Information regarding tides is given on all large scale charts, +and additional information and predictions may be found in the Tide +Tables. On the charts of the United States coast there is a small tide +table giving for the high and low waters the time relations to the +moon's transit and the height relations to the plane of reference. On +the British charts there is a brief statement as to the tides either +at the port on the chart or in the general notes; this ordinarily +gives the interval in hours and minutes between the moon's meridian +passage and the time of high water for the periods of full and new moon, +and also the amount in feet that the spring and neap tides rise above +the plane of reference, and the range of the neap tide. The following is +an example of such a tide note: "H. W. F. and C. Campbellton IV^h 0^m. +Springs rise 10 feet, Neaps 7 feet." + +At some important ports information as to the state of the tide is given +to vessels, either by means of signal balls, or by automatic tidal +indicators, as at the Narrows in New York Harbor, where a large dial +shows to passing vessels the height of the tide, and an arrow indicates +whether it is rising or falling. + +The tidal information becomes important and must be considered in +navigation or in anchoring in waters where the available depth at low +water approximates the draft of the vessel. In the general use of coast +charts it is also important to observe the effect of the stage of tide +on the appearance of many features. Rocks rising some feet above low +water may be entirely submerged at high water. In some areas the aspect +may be radically changed between high and low water by the baring of +extensive shoals or reefs. + +#Currents.# Information, when available, as to currents is given either +by a note or by current arrows placed on the chart at the position of +observation. Additional information as to certain regions is given in +the United States Tide Tables. Tidal currents, flood and ebb, and +currents not due to tidal action are distinguished by symbols, and the +velocity is given in knots, and on some charts is indicated by the +lengths of the arrows. + +Complete and systematic current observations have been made in +comparatively few localities because of the time and expense necessary +to get the full information as to the variations of the currents with +the tides and seasons. Ordinarily therefore the current arrows shown on +charts indicate only the average direction and velocity, or possibly +only the conditions existing at the season when the survey was made. +Oceanic and coast currents are probably much less uniform than might be +inferred from the current streams drawn on maps and charts. A more +systematic investigation of ocean currents is required to fulfill the +needs of navigation. + +The tidal currents seldom turn with the tides, and there may be an +interval of as much as three hours between the time of high tide or +low tide and slack water. This leads to the apparent anomaly that in +cases the current may be running with its greatest velocity at the time +of high or low water, and may be running into a channel for several +hours after the tide commences to fall. It is therefore, evidently, not +safe to draw inferences as to currents solely from the tidal heights. + +There are passages where the tidal currents become of the greatest +importance to navigation, as, for instance, in Seymour Narrows on the +inside route to Alaska, where the current velocity reaches 12 knots and +the interval of apparent slack water lasts but a few minutes. + +#Elevations.# The unit used for elevations is also stated on the face of +the chart, as also the plane to which elevations are referred. On the +United States charts this is generally mean high water and on British +charts the high water of ordinary spring tides. Rocks and islets usually +have figures shown beside them, either in brackets or underscored, which +indicate the height above high water. Rocks which are bare at low water +sometimes have a note "dries" or "bares" so many feet, indicating their +height above low tide, although they are covered at high tide. The +British charts in some regions where there is a large range of tide have +underlined figures in the area between high water and low water +indicating the heights above low water, or the depths of water over the +bank at high water, as explained in each case. + +#Topography.# The land area on most charts is distinguished from the +water area by a stipple or tint; on some charts the topographic features +have, however, been depended upon to bring out the land from the water. +The solid shore line is the high-water line, and should be clear on the +chart; the area between high and low water is sanded or otherwise shaded +on all charts. The relief of the land is represented by hill shading or +by contour lines which are the successive curves of elevation on the +land. Topographic symbols are used for some of the more important +features, such as cliffs, rocky ledges, buildings, bridges, trees, +roads, etc. It is important for the navigator to understand the +significance of the hill representation and the symbols, as they will +aid him in recognizing a coast or island, and in identifying landmarks. + +#Date of survey and publication.# There is usually an authority note on +each chart showing the source of information or date of survey; if on a +coast subject to change, the latter is important. On the United States +Coast Survey charts the date of publication of the edition is given, +and on British and other charts the date of both large and small +corrections. The chart catalogues give the dates of the last editions, +or the dates of extensive corrections, and this affords a means of +seeing whether the copy of the chart in use is the latest edition +available. + + + + +USE OF CHARTS IN NAVIGATION. + + +#Chart working.# In crossing the open and deep portions of the ocean, +where the only data given may be the projection lines and soundings far +deeper than can be reached with navigational sounding machines, the +chart is used to lay out in advance the general course to be followed +and to plot the positions of the vessel at intervals either as +determined by observations or, lacking these, by dead reckoning. When +necessary the courses of the vessel are modified as the plotted +positions are found to fall one side or the other of the proposed +general track. + +The principal operations on a chart are plotting or taking off positions +by latitude and longitude, laying down or taking off bearings, +directions, and courses, plotting or measuring distances, and laying +down or taking off angles. + +To plot a position by its latitude and longitude on a mercator chart, +set a parallel ruler on the adjacent parallel and then move it to the +required latitude as shown by the border scale at either side; then with +a pair of dividers at the upper or lower longitude border scale take the +distance from the nearest meridian and lay this distance off along the +edge of the parallel ruler. The latitude and longitude of a point are +taken from the chart by reversing this process, or with the dividers +only. A direction is laid down on the chart or read from the chart +preferably by using some form of protractor and measuring the angle from +the projection lines. In this country it is more commonly done by +carrying the direction with a parallel ruler either from or to a compass +rose printed on the chart. Distances are measured or laid down on a +mercator chart by using the latitude border scale for the middle +latitude. On polyconic and other larger scale charts distances are +measured from the scales printed on the chart. It should be remarked +that in general where special accuracy is required distances should be +computed and not scaled from any chart, because of the error due to the +distortion of paper in printing. + +The use of protractors on charts in plotting by angles in the +three-point problem will be referred to later. + +The course to be steered to allow for a set due to current or wind may +be obtained by a graphical solution on the chart, though it will be +preferable to do this on other paper, using a larger scale. (Fig. 38.) +The direction and velocity of the set and the course and speed of the +ship may be considered as two sides of a parallelogram of forces, of +which the diagonal is the distance and course made good. To obtain the +course to steer to reach a given point with a given current and speed of +vessel, lay down the direction of the destination; from the starting +point lay off the direction of set and the amount in one hour; from the +extremity of this describe an arc with radius equal to the speed of the +vessel in one hour. A line drawn from the extremity of the direction of +set to the point of intersection of the arc and the course to be made +good will give the direction of the course to be steered, and the point +of intersection will also be the estimated position of the vessel at the +end of the hour's run. + +#Methods of locating a vessel.# The principal methods used for locating +the position of a vessel are by astronomical observations, by dead +reckoning, by compass bearings, by ranges, by horizontal angles, by +soundings, by vertical angles, and by sound. The full discussion of +these methods pertains to navigation and pilotage, and they will be only +briefly referred to here as to their graphical application to charts. + +#Astronomical methods.# There are a number of methods of obtaining the +position of a vessel by astronomical observations. When the position is +computed the chart enters into these only in the plotting of the final +result, so that with one exception these methods will not be referred to +further here. + +The elegant method discovered by an American seaman, Captain Sumner, in +1843, is in part graphical, to be worked out upon the chart. This method +is based on the obvious fact that at any instant there is a point on the +earth having the sun in its zenith and which is the center of circles on +the earth's surface along the circumference of any one of which the +sun's altitude is the same at all points. A short portion of such a +circle may be considered as a straight line and can be determined by +locating one point and its direction, or two points in it. This is known +as a Sumner line. (Fig. 39.) + +From an observation of the sun's altitude and azimuth and an assumed +latitude a position is computed and plotted and a line drawn on the +chart through this position at right angles to the azimuth of the sun as +taken from the azimuth tables and laid off from a meridian. Another +method is to compute positions with two assumed latitudes and plot the +two resulting positions and draw a line through them. The vessel must be +somewhere on the resulting Sumner line. A good determination may be +obtained by the intersection of two Sumner lines obtained from two +observations of the sun with sufficient interval so that there will be a +change of azimuth of as much as 30 degrees to give a fair intersection. +Allowance must be made for the movement of the vessel between the two +observations by drawing a line parallel to the first and at a distance +equal to the distance made good. An excellent intersection may be +obtained by observation of the sun, and before or after it of a star in +the twilight at a different azimuth. + +[Illustration: COURSE TO ALLOW FOR SET, GRAPHICAL SOLUTION + +FIG. 38.] + +[Illustration: POSITION BY INTERSECTION OF SUMNER LINES + +FIG. 39.] + +[Illustration: POSITION BY COMPASS BEARINGS + +FIG. 40.] + +Even a single Sumner line, however, furnishes valuable information, as +it may be combined with other sources of information to obtain an +approximation to the position. The vessel must be somewhere on this +line, and this gives a good check on the position by dead reckoning, or +an intersection may be obtained with a line or bearing of a distant land +object, or a line of soundings may be compared on the chart with the +Sumner line. + +If an observation is taken when the observed heavenly body is bearing +abeam, it is evident that the resulting Sumner line will be the +direction of the course of the vessel, and this fact may be useful in +shaping the course when nearing the land or a danger. + +#Dead reckoning.# When impossible to obtain the position by any other +means, it is computed or plotted from the last determined position, +using the courses and distances run as shown by compass and log and +allowing for effect of current and wind. Because of uncertainties in all +these elements, positions so obtained may be from five to twenty miles +in error in a two-hundred-mile run, depending of course to some extent +on the speed of the vessel. + +#Compass bearings.# A compass bearing of a single object, as a +lighthouse or a tangent to a point of land, laid down on the chart, +shows that the vessel is somewhere on that line, and when combined with +other information, as with a Sumner line or the course by dead reckoning +or the distance by a vertical angle, will give a position whose +correctness of course depends on the accuracy of the data used. Bearings +of two objects not in the same direction give two lines on the chart +whose intersection is the position. This will be very weak if the angle +of intersection is acute, and will become stronger as it approaches a +right angle. A bearing of a third object should be taken when +practicable, as it affords a valuable check in that the three lines +should intersect in the same point; if they do not do so when plotted +the error is either in the observations, or the compass, or the +plotting, or the chart. (Fig. 40). All compass bearings are of course +dependent upon the accuracy of the compass and the knowledge of its +errors due to the local magnetic effect of the ship, and also upon the +correctness with which the magnetic variation from true north is known. +Bearings of near objects should therefore always be preferred, and those +of distant objects considered as giving only approximate positions. An +error of one degree in the bearing of an object 30 miles away will +deflect the plotted line about one-half mile. Because of the facility +with which they may be taken compass bearings are much used for inshore +navigation, but in point of reliability they are inferior to some of the +other methods. + +A single or "danger" bearing of an object is often a valuable guide in +avoiding a danger. For example, a reef may lie to the westward of a line +drawn South 10 deg. East from a lighthouse; in approaching a vessel will +pass safely to the eastward of the reef if the lighthouse is not allowed +to bear any to the northward of North 10 deg. West. (Fig. 41.) + +Two successive bearings of a single object, as, for instance, a +lighthouse, noting the distance run in the interval, afford a convenient +and much used means of locating the position with respect to that +object. Such bearings are drawn on the chart in reversed direction from +the object. The distance run between the bearings, as read by the log +and corrected for current if practicable, is scaled off with dividers +and the course of the vessel is set off with parallel ruler; the latter +is then moved across the two plotted directions until the distance +intercepted between them equals that scaled with the dividers, and the +edge of the ruler then represents the track of the vessel. (Fig. 42.) If +the angle from the bow, or from the course of the vessel, for the second +bearing is double that for the first bearing, the distance from the +object at the second bearing is equal to that run by the vessel in the +interval, and the use of this simple relation is designated as "doubling +the angle on the bow." If the angles between the course and the object +are respectively 45 deg. and 90 deg. when the two bearings are taken on an +object on the shore, the distance that the ship passes offshore when the +object is abeam is equal to the distance run between the two bearings; +this is a much used navigational device, known as the "bow and beam +bearing" or the "four-point bearing." There is an advantage, however, in +using bearings at two and four points (or 22.5 deg. and 45 deg.), as these give +the probable distance that the object will be passed before it is abeam. + +#Ranges.# A valuable line of position is obtained by noting when two +well-situated objects are in range, that is, one back of the other in +the line of sight from the vessel, as, for instance, a church spire +appearing behind a lighthouse or a rock in line with a prominent point. +Such ranges are of course entirely free from compass errors, and should +be noted whenever there is favorable opportunity. The value of the range +in plotting will increase with the distance between the objects, and if +the two are close in proportion to the distance to the vessel the +direction will be weak owing to the uncertainty in drawing a direction +through close points. Artificial ranges are often erected as aids to +navigation, usually to indicate the course to be followed in passing +through a channel. Ranges afford a valuable guide in avoiding dangers, +as for example an inspection of the chart may show that if a certain +lighthouse is kept in line with or open from an islet a dangerous shoal +will be given a good berth; on coasts not well buoyed such danger ranges +are sometimes marked on the charts. (Fig. 43.) + +[Illustration: DANGER BEARING + +FIG. 41.] + +[Illustration: POSITION BY SUCCESSIVE BEARINGS TWO AND FOUR POINT +BEARINGS + +FIG. 42.] + +[Illustration: RANGE TO AVOID DANGER + +FIG. 43.] + +#Horizontal sextant angles.# The location of a position by the +three-point problem, using sextant angles, is much more exact than by +bearings, but is less used because not so well known and also because +additional instruments are required and the conditions are not always +favorable. It is so valuable a method, however, that it should be used, +when necessary, on every well-equipped vessel. A single horizontal angle +taken with a sextant between objects, as two lighthouses, defines the +position of the vessel as somewhere on the circumference of a circle +passing through the two objects and the vessel. A protractor laid on the +chart with two of its arms set at the observed angle and passing through +the two objects, will permit of locating two or more points of this +circle on the chart. This furnishes a line of position which may be +combined with other information to locate the vessel. With a compass +bearing of one of the objects the position may be plotted directly from +the single angle. Two sextant angles measured at the same instant +between three objects furnish one of the most accurate means of locating +the position of a vessel, this being the same method that is ordinarily +used in hydrographic surveying, known as the three-point problem. (Fig. +44.) The two angles are conveniently set off on a three-arm protractor, +which is shifted on the chart until the three arms touch the three +points, when the position of the center is plotted. A third angle to a +fourth point furnishes a valuable check in case of doubt. Two angles may +also be taken to four objects without any common point, and in this case +portions of the two circles of position are plotted and their +intersection will be the ship's position. + +The value of this method depends largely on the selection of favorably +located objects, and it is quite important that the principles of the +three-point problem be understood. If the ship is on or near the +circumference of a circle which passes through the three objects the +position will be very weak, and the same is true if the distance between +any two of the objects is small as compared with the distance from them +to the vessel. A useful general rule is that the position will be strong +if the middle one of the three objects is the nearest to the vessel, +provided that no two of the objects are close together in comparison +with the distance to the vessel. + +A single sextant angle furnishes a means of avoiding a known danger by +using what is known as the horizontal "danger angle." (Fig. 45.) Note +two well-defined objects on the coast either side of the danger to be +avoided and describe a circle through them and passing sufficiently +outside of the reef to give it a safe berth. With a protractor on the +chart note the angle between the objects at any point on the outer part +of this circle. If in passing, the angle at the ship between the two +objects is not allowed to become greater than this "danger angle" the +danger will be given a sufficient berth. This method as well as any use +of sextant angles or bearings depends of course on the accuracy of the +chart, and caution must be used where it is not certain that the chart +depends upon an accurate survey. + +[Illustration: POSITION BY SEXTANT ANGLES THREE POINT PROBLEM + +FIG. 44.] + +[Illustration: HORIZONTAL DANGER ANGLE + +FIG. 45.] + +[Illustration: DISTANCE BY VERTICAL ANGLE] + +[Illustration: VERTICAL DANGER ANGLE + +FIG. 46.] + +#Soundings.# Even if objects cannot be seen, due to distance or thick +weather, the chart furnishes a valuable aid when a vessel has approached +within the limits where it is practicable to obtain soundings. Modern +navigational sounding machines permit of obtaining soundings to depths +of nearly one hundred fathoms without stopping the vessel. A rough check +is at once obtained by comparing such soundings with those given on the +chart for the position carried forward by dead reckoning. If a number of +soundings are taken and plotted on a piece of tracing paper, spaced by +the log readings to the scale of the chart, and this tracing paper is +laid over the chart and shifted in the vicinity of the probable position +until the soundings best agree with those on the chart, a valuable +verification of position may be obtained. This is particularly the case +if the area has been well surveyed, and the soundings taken on the +vessel are accurate, and the configuration of the bottom has marked +characteristics. For instance, in approaching New York the crossing of +the 30, 20, and 10 fathom curves will give a fair warning of the +distance off the Long Island and New Jersey coasts, and soundings across +such a feature as the submerged Hudson gorge extending to the +southeastward of Sandy Hook will give a valuable indication of position. +The taking of soundings should be resorted to even in favorable +conditions, in approaching shoal water, as a check on other means of +locating the vessel. Many marine disasters are attributed to failure to +make sufficient use of the lead, the simplest of navigational aids. + +#Vertical angles.# The vertical angle of elevation of an object whose +height is known will give the distance, and combined with a bearing or +other information this permits of locating a vessel where better means +cannot be used. Distance tables are published for this method. (Fig. +46.) The vertical angle is measured with a sextant and must be the angle +at the ship between the top of the object and the sea level vertically +beneath it; for a hill or mountain, therefore, the eye of the observer +should be near the water. The object should not be so distant that +curvature becomes appreciable. The "vertical danger angle" is a means of +avoiding a known danger, on a principle similar to that of the +horizontal danger angle; that is, the angle of elevation of a known +object is not permitted to become greater than a fixed amount depending +on the distance from the object to the danger to be avoided. + +#Positions by sound.# In thick weather sound affords a valuable aid to +the navigator. In narrow passages noting the echo of the whistle from a +cliff is a method resorted to, as for instance in Puget Sound and along +the Alaska coast. Fog whistles and bell buoys are maintained at many +places. Submarine bells have recently been introduced at a number of +points along the Atlantic coast, and vessels may be equipped to receive +these submarine signals transmitted through the water, which indicate +also the general direction from which the sound comes. + +#Need of vigilance.# Too great importance cannot be attached to frequent +verification of positions by the best available means, particularly when +approaching the land. Neglect of this or overconfidence has caused many +disasters. A notable instance was the loss of one of the largest Pacific +steamers on the coast of Japan in March, 1907. In the afternoon of a +clear day this vessel ran on to a well-known reef about a mile from a +lighthouse, resulting in the total loss of vessel and cargo valued at +three and a half million dollars. The captain was so confident of his +position and that he was giving the reef a sufficient berth that he laid +down no bearings on the chart and took no soundings. + +[Illustration: FIG. 47. FIELD'S PROTRACTOR AND PARALLEL RULER IN USE ON +A CHART, PLOTTING BEARING OF A LIGHTHOUSE.] + +#Instruments.# The principal instruments needed for use with charts are; +dividers for taking off distances and latitudes and longitudes, parallel +ruler for transferring directions to or from a compass rose and for +taking off or plotting the latitude on a mercator chart, protractor of +180 degrees for reading the angle with the meridian of any direction or +for laying off on the chart any given angle with the meridian, and +three-arm or other full-circle protractor for plotting a position by the +three-point problem. + +Parallel rulers on the principle of Field's are strongly recommended for +chart work, as they combine in a single instrument the advantages of a +parallel ruler and a 180-degree protractor. Any direction can be read or +laid off by simply moving the parallel ruler to the nearest projection +line, which is a process not only more convenient than referring to the +compass rose printed on the chart but also more accurate because of the +longer radius. These instruments can also be used the same as a plain +parallel ruler. Field's parallel rulers are made in two forms, one +rolling and the other sliding. The former is a single ruler with edge +graduated 90 degrees either way, and mounted on rollers; it is the most +rapid instrument for reading or laying off a direction, but it requires +a smooth surface. The latter is an ordinary two-bar parallel ruler with +edge when closed graduated 90 degrees either way; it is a very +serviceable instrument and probably more to be depended upon for +ordinary use than the rolling form. Some form of combined protractor and +parallel ruler should be in every navigational equipment, and it is +unfortunate that these instruments are not better known in this country. +There are other forms of half-circle protractors which are used on the +same principle, that is, of bringing the center on to a projection line +and reading where the line cuts the border graduation of the protractor. +Thus a semicircular protractor is used with a separate straight edge, +along which it is slid to the nearest meridian; another form is the +simple circular protractor with a thread fastened at the center. All +these forms of protractors, it will be noted, are intended to work from +the true meridian, and they are usually graduated in degrees only; the +use of degrees instead of points is becoming much more general in +navigational work, and reference to the true meridian is also more +common than formerly. + +The standard three-arm protractor, or station pointer, as it is known to +the English, should be a part of every navigational outfit because of +its value in locating a position by the three-point problem. A recent +American invention, Court's three-arm protractor, is an instrument made +of celluloid for the same purpose. It should not be considered as a +substitute for the standard metal instrument, but it is a simple, cheap, +and handy supplement to it, as it may be readily used for small angles +and short distances where there are mechanical difficulties in working +with the metal three-arm protractor. Other protractors can be used for +the three-point problem, as, for instance, Cust's protractor on +celluloid, on which the angles are drawn in pencil and erased, and the +tracing-paper protractor. + +#Degree of reliance on charts.# The value of a chart must not be judged +alone from its general appearance, as skill in preparation and +publication may give a handsome appearance to an incomplete survey. On +the other hand a thorough survey might through poor preparation result +in a chart defective either in information or in utility. + +[Illustration: FIG. 48. THREE-ARM PROTRACTOR IN USE ON A CHART, PLOTTING +POSITION FROM TWO ANGLES.] + +The degree of completeness of the soundings, the character of the +region, and the date of the survey should be taken into account in +deciding as to the amount of reliance to be placed on the chart. Areas +where the soundings are not distributed with fair uniformity may be +assumed not to have been completely surveyed. Caution should be used in +navigating on charts where the survey is not complete, and even where +careful surveys exist care must be taken if the bottom is of very +irregular nature with lumps near the navigable depth, as for instance on +some of the coral reef coasts. Isolated soundings shoaler than the +surrounding depths should be avoided, as there may be less water than +shown. In such a region, unless the whole area is dragged, it is +impossible to make it entirely certain that all obstructions are +charted. + +While an immense amount of faithful work has been put into the +preparation of many charts, the user must constantly exercise his own +judgment as to the reliance to be placed on them. A coast is not to be +considered as clear unless it is shown to be; buoys may get adrift and +be in a different position or be gone altogether; fog signals vary in +distinctness owing to atmospheric conditions; extreme or unusual tides +may fall below the plane of reference; owing to strong winds the actual +tide may differ from the predicted tide. Errors sometimes creep in from +various sources, such as those due to different reference longitudes or +the use of a corrected longitude for a portion of the chart without +changing other positions to which the same correction is applicable; +clerical and printing errors may occur; there are sometimes omissions in +surveys; a feature may get plotted in two different positions; tide rips +are reported as breakers and floating objects as rocks or islands, and +thus many dangers have gotten on the charts which cannot be found again, +and false reports are sometimes made to shield some one from blame. Most +of these classes of errors and uncertainties, however, disappear in the +use of charts of a thoroughly surveyed coast. + +#Use the latest editions of charts.# The latest edition of a chart +should always be used and should be corrected for all notices since its +issue. Carelessness or false economy in not providing the largest scale +or the latest chart has been the cause of more than one marine disaster. + +The British Board of Trade issue the following official notice to +shipowners and agents: "The attention of the Board of Trade has +frequently been called to cases in which British vessels have been +endangered or wrecked through the masters' attempting to navigate them +by means of antiquated or otherwise defective charts. The Board of Trade +desires, therefore, to direct the especial attention of shipowners and +their agents to the necessity of seeing that the charts taken or sent on +board their ships are corrected to the time of sailing. Neglect to +supply a ship with proper charts will be brought prominently before the +Court of Inquiry in the event of a wreck occurring from that cause." + +The following is a translation of a notice in the preface to the +catalogue of charts published by the German government: "Owners and +masters of vessels are apprised that cases of marine accidents in which +the casualty was due to antiquated or erroneous charts, have frequently +been before the admiralty courts. In consequence of this, the +'Instructions for the prevention of accidents to steamers and sailing +vessels,' issued by the Seeberufsgenossenschaft have been amended by the +following additional paragraph: 'It is obligatory upon every master, +except when engaged in local coastwise navigation, to keep the Notices +to Mariners regularly, and with the aid of them to carefully keep his +charts up to date.'" + +The British shipping laws provide that a ship may not be sent to sea in +such an unseaworthy state that the life of any person is thereby +endangered, and the House of Lords has defined the term "seaworthy" to +mean "in a fit state as to repairs, equipment, and crew, and in all +other respects, to encounter the ordinary perils of the voyage." Proper +charts and sailing directions are a necessary part of the equipment of a +vessel, and the courts have frequently inquired into this. + +The records of the British courts, however, show that even in recent +years many ships have been damaged or lost owing directly or indirectly +to failure to have the latest information on board. The following are +instances from these records. + +In 1890 the steamer _Dunluce_ was lost owing to the use of an old +edition of the Admiralty chart which showed a depth of 4-1/2 fathoms on +the Wikesgrund, whereas the later chart showed much less water. In this +case the master had requested his ship chandler to send him the latest +chart. + +In 1891 the steamer _St. Donats_ got ashore on a patch which was not +shown on the chart in use, which was privately published in 1881; the +danger was, however, shown on the Admiralty chart corrected to 1889. + +Also in 1891 the steamer _Trent_ was lost on the Missipezza Rock in the +Adriatic. The ship was navigated by a private chart published in 1890 +which did not show this rock, and by sailing directions published in +1866. + +The steamer _Aboraca_, stranded in the Gulf of Bothnia in 1894, was +being navigated by a chart corrected to 1881 which did not show that the +Storkallagrund light-vessel had been moved eight miles. + +The steamer _Ravenspur_ was lost on Bilbao Breakwater owing to the use +of a chart not up to date which did not show the breakwater. In 1898 the +steamer _Cromarty_ was lost in attempting to enter Ponta Delgada harbor, +and in 1901 the steamer "Dinnington" was lost by steaming on to the new +breakwater in Portland harbor; both of these disasters were likewise due +to the use of old charts which did not show the breakwaters. In these +three cases the masters of the vessels had authority to obtain the +necessary charts at the owners' expense. + +Not so, however, in the following case from the finding of a British +marine court in 1877: "The primary cause of the ship's getting on shore +was due to the master's being guided in his navigation by an obsolete +Admiralty chart dated September 1, 1852, and corrected to April, 1862, +and on which no lights are shown to exist either in ... or ... and to +his not being supplied with the latest sailing directions. The Court, +considering that the master was obliged to furnish himself with +chronometer, barometer, sextant, charts, sailing directions, and +everything necessary for the navigation of his vessel out of his private +resources, which, under very favorable circumstances, might perhaps +reach L150 a year, find themselves unable in this instance to pass a +heavier censure upon him than that he be severely reprimanded." + +The loss of the German steamer _Baker_ on the coast of Cuba on January +31, 1908, was declared by the marine court at Hamburg to be due in part +to the use of an unofficial chart which did not show the latest surveys +on that coast. + +#Use the largest scale charts.# The largest scale chart available should +be employed when entering channels, bays, or harbors, as it gives +information with more clearness and detail, positions may be more +accurately plotted, and sometimes it is the first corrected for new +information. + +The records of the courts of inquiry also show cases where vessels have +been wrecked owing to the use of charts of too small scale. + +In 1890 the steamer _Lady Ailsa_ was lost on the Plateau du Four. The +only chart on board for this locality was a general chart of the Bay of +Biscay, and the stranding was due to the master's mistaking one buoy for +another. The court found that the chart, although a proper one for +general use, was not sufficient for the navigation of a vessel in such +narrow waters and on such a dangerous coast. + +The _Zenobia_ was stranded on the San Thome Bank in 1891. On this vessel +the owners were to furnish the chronometers and the master the charts +and sailing directions. The master was, however, apparently satisfied +with only a general chart of the South Atlantic for navigation on the +coast of Brazil, and had no sailing directions at all. + +#The depth curves# on charts furnish a valuable guide, and if the curves +are lacking or broken in some parts it is usually a sign that the +information is incomplete. The 100-fathom curve is a general warning of +approach to the coast. The 10-fathom curve on rocky coasts should be +considered as a danger curve, and caution used after crossing it. The +5-fathom curve is the most important for modern vessels of medium draft, +as it indicates for them the practical limit of navigation. The 3, 2, +and 1-fathom curves are a guide to smaller vessels, but have less +significance than formerly because of the increase of draft of vessels. + +#The shrinkage of paper#, especially in plate printing, has been +referred to. This introduces two possible sources of error: first, the +shrinkage being different in the two directions, any scale printed on +the chart will be accurate only when used in a direction parallel to +itself; second, for the same reason, angles and directions will be +somewhat distorted. Fortunately these errors are not serious in the +ordinary navigational use of a chart, but they should not be overlooked +when accurate plotting or measuring of distances is attempted on a +plate-printed chart. + +The actual shrinkage measured on charts printed from plates varies from +1/3 inch to 1 inch in a length of chart of 36 inches. On British and +American plate printed charts the shrinkage is usually from two to +nearly three times as much in one direction as it is in the other. + +#Care of charts.# In order that they may be properly used charts should +be filed flat and not rolled. They should be systematically arranged so +that the desired chart can be instantly found. They should be cared for +and when in bad condition replaced by new copies. They can be most +conveniently filed in shallow drawers, thus avoiding the placing of many +charts in a single drawer. The latter is a common fault; it not only +increases the labor of handling the charts but adds to the liability of +their injury. + + + + +PUBLICATIONS SUPPLEMENTING NAUTICAL CHARTS. + + +There are several publications in book and in chart form which are +either necessary or convenient for use in connection with nautical +charts. These comprise the coast pilots, notices to mariners, tide +tables, light and buoy lists, and various special charts. + +#Coast pilots#, or sailing directions, are books giving descriptions of +the main features, as far as of interest to seamen, of the coast and +adjacent waters, with directions for navigation. They contain much +miscellaneous information of value to the mariner, especially the +stranger. Although they contain additional facts which cannot be shown +on the charts, they are not at all intended to supersede the latter; the +mariner should in general rely on the charts. The sailing directions can +be less readily corrected than the charts, and in all cases where they +differ the charts are to be taken as the guide. + +The most extensive series of sailing directions is that published by the +British Admiralty, comprising fifty-six volumes and including all the +navigable regions of the world. In the United States the Coast and +Geodetic Survey publishes ten volumes of coast pilots for the Atlantic, +Gulf, and Pacific coasts, Porto Rico, and southeastern Alaska, and eight +volumes of sailing directions for Alaska and the Philippine Islands. The +United States Hydrographic Office publishes sixteen volumes of sailing +directions for various parts of the world. + +#Notices to Mariners# are published at frequent intervals, giving all +important corrections, which should be at once applied by hand to the +charts, such as rocks or shoals discovered and lights and buoys +established or moved. New charts, new editions, and canceled charts are +also announced. + +These notices should be carefully examined and the necessary corrections +made on all charts of the sets in use on the vessel. A chart should be +considered as a growing rather than a finished instrument, and constant +watchfulness is required to see that it is kept up to date. Neglect of +this may cause shipwreck, as the following instance shows. Report came +to Manila in 1904 that there was a low sand islet lying off the very +poorly charted northeast coast of Samar; this information was promptly +published in the local Notice to Mariners. About a month later a small +steamer was sent to land some native constabulary on that coast. The +captain failed to obtain or observe this notice, and approached the +coast before daylight on a course which led directly across the sand +islet. The vessel was driven far up on the sand, where it still lies. + +In the United States, weekly Notices to Mariners are published by the +Department of Commerce and Labor for the coasts under the jurisdiction +of the United States, and by the Navy Department for all regions. These +notices are distributed free and can be obtained from chart agents and +consular officers. In Great Britain the notices are published at +frequent intervals by the Hydrographic Office, and practically all +countries issuing charts also issue such notices. Information as to +important changes in lights and other announcements of navigational +interest are also sometimes printed in the marine columns of newspapers +and in nautical periodicals. + +#Tide Tables.# Brief information as to the time and height of the tide +is usually for convenience given on the face of the chart. More complete +information is published in the Tide Tables, with which every navigator +should be provided. "The Tide Tables for United States and foreign +ports," published annually in advance by the United States Coast and +Geodetic Survey, give complete predictions of the time and height of +high and low water for each day of the year for 70 of the principal +ports of the world, and the tidal differences from some principal port +for 3000 subordinate ports. The other leading nations also publish +annual tide tables; those of the British government are entitled "Tide +Tables for British and Irish ports, and also the times of high water for +the principal places on the globe." + +#Light and buoy lists.# Brief information as to all artificial aids to +navigation is shown on the charts. Every vessel should also have on +board the latest official light and buoy lists, which give a more +detailed description than can be placed on the charts. + +Light and buoy lists for the coasts of the United States are published +annually by the Light-House Board. The United States Hydrographic Office +publishes a "List of Lights of the World" (excepting the United States), +in three volumes. + +The British Hydrographic Office publishes eight volumes of Lists of +Lights, and these are corrected annually. + +#Chart catalogues# are published in connection with all series of +charts. They give the particulars and price of each chart published, and +are usually arranged in geographical order, with both alphabetical and +numerical indexes, for convenience in finding charts either by position, +name, or number. + +#Charts for special purposes.# There are various special charts +published for the benefit of mariners, although not intended for direct +use in plotting the course of a vessel or in locating its position. Some +of the more important of these are mentioned below. + +#Gnomonic charts# are intended solely for laying down the great circle +or shortest practicable courses between points, for which purpose they +are very convenient. Their use has already been described. The United +States Hydrographic Office publishes six such charts, for the North +Atlantic, South Atlantic, Pacific, North Pacific, South Pacific, and +Indian Oceans. + +#Current charts# are published by the British Hydrographic Office for +the various oceans; these usually show the average ocean currents, but +for the Atlantic there are monthly and for the Pacific quarterly current +charts. + +#Magnetic variation charts# are published by both the United States and +British governments. They show on a mercator chart of the world the +isogonic lines, or lines along which the variation of the needle from +true north is the same. The lines are drawn for each degree of +variation. The annual change in the variation is also indicated. + +Other magnetic charts are published showing the lines of equal magnetic +dip, horizontal magnetic force, and vertical magnetic force. + +#Meteorological ocean charts# are published by several governments, +including the United States, Great Britain, and Germany, and give the +average weather conditions, winds, fogs, currents, ice, tracks of +storms, and other information. "Pilot charts" of the North Atlantic and +North Pacific Oceans are issued by the United States Hydrographic Office +about the first of each month, and give "a forecast of the weather for +the ensuing and a review of that for the preceding month, together with +all obtainable information as to the most available sailing and steam +routes, dangers to navigation, ice, fog, derelicts, etc., and any +additional information that may be received of value to navigation." +Mariners in all parts of the world have joined in contributing the +information which has been used in compiling these pilot charts. + +#Track charts# are published by the British and United States +governments. That of the latter is entitled "Track and distance chart of +the world, showing the routes traversed by full-powered steamers between +the principal ports of the world, and the corresponding distances." + +#Telegraph charts# are published showing the "telegraphic connections +afforded by the submarine cables and the principal overland telegraph +lines." + +#Index charts# are outline plans showing the area covered by each chart +of a series, and furnish a convenient means of finding a chart of any +desired region or of selecting the most suitable chart for any purpose. +These index charts are published either in sets, showing all the charts +of a series, or are bound into the chart catalogues. + +#Star charts# are included in navigational series, and are conveniently +arranged for use on shipboard in identifying the brighter stars. The +United States Hydrographic Office publishes two, constellations of the +northern and of the southern hemispheres. + +#Explanatory sheets# are published in connection with various series of +charts, giving explanations of the symbols and abbreviations used and of +other important features. In the United States the Coast and Geodetic +Survey has issued a small pamphlet, "Notes on the use of charts," which +contains explanations of its chart symbols, and the Hydrographic Office +has published "A manual of conventional symbols and abbreviations in use +on the official charts of the principal maritime nations." + + + + +INDEX + + + PAGE + + Aids to navigation, 118 + + Arbitrary projection, 79 + + Astronomical observations, 32 + + Astronomical positions, 126 + + + Bearings, position by, 130 + + Board of Trade notice, 148 + + + Care of charts, 153 + + Catalogues of charts, 157 + + Changes in the coast, 98 + + Chart making, development of, 6 + + Chart publications of various nations, 18 + + Charts, earliest nautical, 6 + + Charts, loxodromic, 7 + + Charts, plain, 8 + + Chart schemes, 67 + + Chart working, 124 + + Coast and Geodetic Survey, United States, 13 + + Coast pilots, 154 + + Compass bearings, 130 + + Compass, nautical use of, 6 + + Compass, variation of, 7 + + Compilation of information, 67 + + Correction of charts, method of, 110 + + Cosa, Juan de la, 8 + + Current charts, 157 + + Currents, 50, 121 + + + Danger angle, horizontal, 136 + + Danger bearing, 131 + + Danger range, 132 + + Dangers, reports of, 56 + + Dates on charts, 123 + + Dead reckoning, 129 + + Depth curves, 116, 152 + + Depths, unit for, 19, 116 + + Depth units, relation of, 118 + + Directions on charts, 115 + + Distances, measured on chart, 125 + + Distribution of charts, 96 + + Doubling angle on bow, 131 + + Draft of vessels, 97 + + Dragging for dangers, 55 + + + Earthquakes, 109 + + Electrotyping plates, 89 + + Elevations, 122 + + Engraving machines, 89 + + Engraving on copper, 84 + + Engraving on stone, 93 + + Eskimo map, 1 + + Etching on copper, 95 + + Explanatory sheets, 159 + + + Flattening of the earth, 3 + + France, establishment of chart office, 10 + + + Geographic position on charts, 115 + + Geography, early, 2 + + Germany, contributions to hydrography, 14 + + Gnomonic charts, 79, 157 + + Gnomonic projection, 74 + + Great Britain, contributions to geography, 14 + + + Holland, development of chart making, 10 + + Hydrographic Office, British, 13 + + Hydrographic Office, United States, 13 + + Hydrography, 40 + + + Index charts, 158 + + Information on charts, 23 + + Instruments used on charts, 141 + + + Lake Survey, United States, 13 + + Largest scale chart, 151 + + Latest editions of charts, 148 + + Light and buoy lists, 156 + + Lithographic printing, 94 + + Locating a vessel, 126 + + Longitude, initial, 19 + + Longitude, uncertainties in, 10 + + + Magnetic charts, 157 + + Magnetic variation, 56 + + Map, earliest, 2 + + Map making, development of, 2 + + Maps, need of, 1 + + Maritime surveys, extension of, 17 + + Mercator chart, history, 8 + + Mercator projection, 68 + + Meteorological charts (pilot charts), 158 + + + Navigation, use of charts in, 124 + + Notices to mariners, 111, 155 + + + Paper, shrinkage of, 152 + + Parallel rulers, Field's, 141 + + Photolithography, 93 + + Plane of reference, 20, 119 + + Plotting positions, 124 + + Polyconic projection, 73 + + Printing, plate, 84, 90 + + Privately published charts, 21 + + Progress of hydrographic surveys, 17 + + Projection, explanation of, 114 + + Projections, 68, 114 + + Protractor, three-arm, 144 + + Ptolemy, 3 + + Publication of charts, methods, 84 + + Purpose of charts, 22 + + + Ranges, 132 + + Reading charts, 112 + + Reliance on charts, 144 + + Reports of dangers, erroneous, 57 + + Requirements for charts, 23 + + Revision of charts, need of, 97 + + Rock, Brooklyn, 50 + + + Sailing directions, early, 4 + + Sailing directions, 154 + + Scale equivalents, 113 + + Scales of charts, 79, 112 + + Set, graphical allowance for, 125 + + Sextant angles, 132 + + Sheets for surveys, 39 + + Shrinkage of paper, 152 + + Sound, position by, 140 + + Sounding machines, 49 + + Soundings, position by, 136 + + Star charts, 159 + + Station pointer, 144 + + Steamer for surveying, 49 + + Sumner's method, 126 + + Supplementary publications, 154 + + Surveys on foreign coasts, 14 + + Surveys, need of thorough, 31 + + Symbols on charts, 20 + + + Telegraph charts, 158 + + Three-point problem, 132, 135 + + Tides, 50, 120 + + Tide tables, 156 + + Topography, 39 + + Topography on charts, 123 + + Track charts, 158 + + Triangulation, 32 + + + Uniformity in charts, 21 + + Use of charts in navigation, 124 + + + Vertical angles, 139 + + Vigias, removal of, 62 + + Vigilance, need of, 140 + + Volcanic action, 109 + + + Wrecks due to deficient charts, 149 + + + + + SHORT-TITLE CATALOGUE + OF THE + PUBLICATIONS + OF + JOHN WILEY & SONS, + NEW YORK. + LONDON: CHAPMAN & HALL, LIMITED. + + ARRANGED UNDER SUBJECTS. + + +Descriptive circulars sent on application. Books marked with an asterisk +(*) are sold at _net_ prices only. All books are bound in cloth unless +otherwise stated. + + +AGRICULTURE. + + Armsby's Manual of Cattle-feeding. 12mo, $1 75 + Principles of Animal Nutrition. 8vo, 4 00 + Budd and Hansen's American Horticultural Manual: + Part I. Propagation, Culture, and Improvement. 12mo, 1 50 + Part II. Systematic Pomology. 12mo, 1 50 + Elliott's Engineering for Land Drainage. 12mo, 1 50 + Practical Farm Drainage. 12mo, 1 00 + Graves's Forest Mensuration. 8vo, 4 00 + Green's Principles of American Forestry. 12mo, 1 50 + Grotenfelt's Principles of Modern Dairy Practice. (Woll.) 12mo, 2 00 + Hanausek's Microscopy of Technical Products. (Winton.) 8vo, 5 00 + Herrick's Denatured or Industrial Alcohol. 8vo, 4 00 + Maynard's Landscape Gardening as Applied to Home Decoration. 12mo, 1 50 + * McKay and Larsen's Principles and Practice of + Butter-making. 8vo, 1 50 + Sanderson's Insects Injurious to Staple Crops. 12mo, 1 50 + * Schwarz's Longleaf Pine in Virgin Forest. 12mo, 1 25 + Stockbridge's Rocks and Soils. 8vo, 2 50 + Winton's Microscopy of Vegetable Foods. 8vo, 7 50 + Woll's Handbook for Farmers and Dairymen. 16mo, 1 50 + + +ARCHITECTURE. + + Baldwin's Steam Heating for Buildings. 12mo, 2 50 + Bashore's Sanitation of a Country House. 12mo, 1 00 + Berg's Buildings and Structures of American Railroads. 4to, 5 00 + Birkmire's Planning and Construction of American Theatres. 8vo, 3 00 + Architectural Iron and Steel. 8vo, 3 50 + Compound Rivetee Girders as Applied in Buildings. 8vo, 2 00 + Planning and Construction of High Office Buildings. 8vo, 3 50 + Skeleton Construction in Buildings. 8vo, 3 00 + Brigg's Modern American School Buildings. 8vo, 4 00 + Carpenter's Heating and Ventilating of Buildings. 8vo, 4 00 + Freitag's Architectural Engineering. 8vo, 3 50 + Fireproofing of Steel Buildings. 8vo, 2 50 + French and Ives's Stereotomy. 8vo, 2 50 + Gerhard's Guide to Sanitary House-inspection. 16mo, 1 00 + Sanitation of Public Buildings. 12mo, 1 50 + Theatre Fires and Panics. 12mo, 1 50 + * Greene's Structural Mechanics. 8vo, 2 50 + Holly's Carpenters' and Joiners' Handbook. 18mo, 75 + Johnson's Statics by Algebraic and Graphic Methods. 8vo, 2 00 + Kellaway's How to Lay Out Suburban Home Grounds. 8vo, 2 00 + Kidder's Architects' and Builders' Pocket-book. + Rewritten Edition. 16mo, mor., 5 00 + Merrill's Stones for Building and Decoration. 8vo, 5 00 + Non-metallic Minerals: Their Occurrence and Uses. 8vo, 4 00 + Monckton's Stair-building. 4to, 4 00 + Patton's Practical Treatise on Foundations. 8vo, 5 00 + Peabody's Naval Architecture. 8vo, 7 50 + Rice's Concrete-block Manufacture. 8vo, 2 00 + Richey's Handbook for Superintendents of Construction. 16mo, mor., 4 00 + * Building Mechanics' Ready Reference Book: + * Carpenters' and Woodworkers' Edition. 16mo, morocco, 1 50 + * Cementworkers and Plasterer's Edition. (In Press.) + * Stone- and Brick-mason's Edition. 12mo, mor., 1 50 + Sabin's Industrial and Artistic Technology of Paints + and Varnish. 8vo, 3 00 + Siebert and Biggin's Modern Stone-cutting and Masonry. 8vo, 1 50 + Snow's Principal Species of Wood. 8vo, 3 50 + Sondericker's Graphic Statics with Applications to Trusses, + Beams, and Arches. 8vo, 2 00 + Towne's Locks and Builders' Hardware. 18mo, morocco, 3 00 + Turneaure and Maurer's Principles of Reinforced Concrete + Construction. 8vo, 3 00 + Wait's Engineering and Architectural Jurisprudence. 8vo, 6 00 + Sheep, 6 50 + Law of Operations Preliminary to Construction in + Engineering and Architecture. 8vo, 5 00 + Sheep, 5 50 + Law of Contracts. 8vo, 3 00 + Wilson's Air Conditioning, (In Press.) + Wood's Rustless Coatings: Corrosion and Electrolysis of Iron + and Steel. 8vo, 4 00 + Worcester and Atkinson's Small Hospitals, Establishment and + Maintenance, Suggestions for Hospital Architecture, + with Plans for a Small Hospital. 12mo, 1 25 + The World's Columbian Exposition of 1893. Large 4to, 1 00 + + +ARMY AND NAVY. + + Bernadou's Smokeless Powder, Nitro-cellulose, and the Theory + of the Cellulose Molecule. 12mo, 2 50 + Chase's Screw Propellers and Marine Propulsion. 8vo, 3 00 + Cloke's Gunner's Examiner. 8vo, 1 50 + Craig's Azimuth. 4to, 3 50 + Crehore and Squier's Polarizing Photo-chronograph. 8vo, 3 00 + * Davis's Elements of Law. 8vo, 2 50 + * Treatise on the Military Law of United States. 8vo, 7 00 + Sheep, 7 50 + De Brack's Cavalry Outposts Duties. (Carr.) 24mo, morocco, 2 00 + Dietz's Soldier's First Aid Handbook. 16mo, morocco, 1 25 + * Dudley's Military Law and the Procedure of + Courts-martial. Large 12mo, 2 50 + Durand's Resistance and Propulsion of Ships. 8vo, 5 00 + * Dyer's Handbook of Light Artillery. 12mo, 3 00 + Eissler's Modern High Explosives. 8vo, 4 00 + * Fiebeger's Text-book on Field Fortification. Small 8vo, 2 00 + Hamilton's The Gunner's Catechism. 18mo, 1 00 + * Hoff's Elementary Naval Tactics. 8vo, 1 50 + Ingalls's Handbook of Problems in Direct Fire. 8vo, 4 00 + * Lissak's Ordnance and Gunnery. 8vo, 6 00 + * Lyons's Treatise on Electromagnetic Phenomena. + Vols. I. and II. 8vo, each, 6 00 + * Mahan's Permanent Fortifications. (Mercur.) 8vo, half morocco, 7 50 + Manual for Courts-martial. 16mo, morocco, 1 50 + * Mercur's Attack of Fortified Places. 12mo, 2 00 + * Elements of the Art of War. 8vo, 4 00 + Metcalfe's Cost of Manufactures--And the Administration + of Workshops. 8vo, 5 00 + * Ordnance and Gunnery. 2 vols. 12mo, 5 00 + Murray's Infantry Drill Regulations. 18mo, paper, 10 + Nixon's Adjutants' Manual. 24mo, 1 00 + Peabody's Naval Architecture. 8vo, 7 50 + * Phelps's Practical Marine Surveying. 8vo, 2 50 + Powell's Army Officer's Examiner. 12mo, 4 00 + Sharpe's Art of Subsisting Armies in War. 18mo, morocco, 1 50 + * Tupes and Poole's Manual of Bayonet Exercises and + Musketry Fencing. 24mo, leather, 50 + Weaver's Military Explosives. 8vo, 3 00 + Wheeler's Siege Operations and Military Mining. 8vo, 2 00 + Winthrop's Abridgment of Military Law. 12mo, 2 50 + Woodhull's Notes on Military Hygiene. 16mo, 1 50 + Young's Simple Elements of Navigation. 16mo, morocco, 2 00 + + +ASSAYING. + + Fletcher's Practical Instructions in Quantitative + Assaying with the Blowpipe. 12mo, morocco, 1 50 + Furman's Manual of Practical Assaying. 8vo, 3 00 + Lodge's Notes on Assaying and Metallurgical Laboratory + Experiments. 8vo, 3 00 + Low's Technical Methods of Ore Analysis. 8vo, 3 00 + Miller's Manual of Assaying. 12mo, 1 00 + Cyanide Process. 12mo, 1 00 + Minet's Production of Aluminum and its Industrial Use. + (Waldo.) 12mo, 2 50 + O'Driscoll's Notes on the Treatment of Gold Ores. 8vo, 2 00 + Ricketts and Miller's Notes on Assaying. 8vo, 3 00 + Robine and Lenglen's Cyanide Industry. (Le Clerc.) 8vo, 4 00 + Ulke's Modern Electrolytic Copper Refining. 8vo, 3 00 + Wilson's Cyanide Processes. 12mo, 1 50 + Chlorination Process. 12mo, 1 50 + + +ASTRONOMY. + + Comstock's Field Astronomy for Engineers. 8vo, 2 50 + Craig's Azimuth. 4to, 3 50 + Crandall's Text-book on Geodesy and Least Squares. 8vo, 3 00 + Doolittle's Treatise on Practical Astronomy. 8vo, 4 00 + Gore's Elements of Geodesy. 8vo, 2 50 + Hayford's Text-book of Geodetic Astronomy. 8vo, 3 00 + Merriman's Elements of Precise Surveying and Geodesy. 8vo, 2 50 + * Michie and Harlow's Practical Astronomy. 8vo, 3 00 + * White's Elements of Theoretical and Descriptive Astronomy. 12mo, 2 00 + + +BOTANY. + + Davenport's Statistical Methods, with Special + Reference to Biological Variation. 16mo, morocco, 1 25 + Thome and Bennett's Structural and Physiological Botany. 16mo, 2 25 + Westermaier's Compendium of General Botany. (Schneider.) 8vo, 2 00 + + +CHEMISTRY. + + * Abegg's Theory of Electrolytic Dissociation. (Von Ende.) 12mo, 1 25 + Adriance's Laboratory Calculations and Specific Gravity + Tables. 12mo, 1 25 + Alexeyeff's General Principles of Organic Synthesis. + (Matthews.) 8vo, 3 00 + Allen's Tables for Iron Analysis. 8vo, 3 00 + Arnold's Compendium of Chemistry. (Mandel.) Small 8vo, 3 50 + Austen's Notes for Chemical Students. 12mo, 1 50 + Beard's Mine Gases and Explosions. (In Press.) + Bernadou's Smokeless Powder.--Nitro-cellulose, and Theory + of the Cellulose Molecule. 12mo, 2 50 + Bolduan's Immune Sera. 12mo, 1 50 + * Browning's Introduction to the Rarer Elements. 8vo, 1 50 + Brush and Penfield's Manual of Determinative Mineralogy. 8vo, 4 00 + * Claassen's Beet-sugar Manufacture. (Hall and Rolfe.) 8vo, 3 00 + Classen's Quantitative Chemical Analysis by Electrolysis. + (Boltwood.) 8vo, 3 00 + Cohn's Indicators and Test-papers. 12mo, 2 00 + Tests and Reagents. 8vo, 3 00 + Crafts's Short Course in Qualitative Chemical Analysis. + (Schaeffer.) 12mo, 1 50 + * Danneel's Electrochemistry. (Merriam.) 12mo, 1 25 + Dolezalek's Theory of the Lead Accumulator (Storage Battery). + (Von Ende.) 12mo, 2 50 + Drechsel's Chemical Reactions. (Merrill.) 12mo, 1 25 + Duhem's Thermodynamics and Chemistry. (Burgess.) 8vo, 4 00 + Eissler's Modern High Explosives. 8vo, 4 00 + Effront's Enzymes and their Applications. (Prescott.) 8vo, 3 00 + Erdmann's Introduction to Chemical Preparations. (Dunlap.) 12mo, 1 25 + * Fischer's Physiology of Alimentation. Large 12mo, 2 00 + Fletcher's Practical Instructions in Quantitative + Assaying with the Blowpipe. 12mo, morocco, 1 50 + Fowler's Sewage Works Analyses. 12mo, 2 00 + Fresenius's Manual of Qualitative Chemical Analysis. (Wells.) 8vo, 5 00 + Manual of Qualitative Chemical Analysis. Part I. + Descriptive. (Wells.) 8vo, 3 00 + Quantitative Chemical Analysis. (Cohn.) 2 vols. 8vo, 12 50 + Fuertes's Water and Public Health. 12mo, 1 50 + Furman's Manual of Practical Assaying. 8vo, 3 00 + * Getman's Exercises in Physical Chemistry. 12mo, 2 00 + Gill's Gas and Fuel Analysis for Engineers. 12mo, 1 25 + * Gooch and Browning's Outlines of Qualitative Chemical + Analysis. Small 8vo, 1 25 + Grotenfelt's Principles of Modern Dairy Practice. (Woll.) 12mo, 2 00 + Groth's Introduction to Chemical Crystallography. (Marshall.) 12mo, 1 25 + Hammarsten's Text-book of Physiological Chemistry. (Mandel.) 8vo, 4 00 + Hanausek's Microscopy of Technical Products. (Winton.) 8vo, 5 00 + * Haskin's and MacLeod's Organic Chemistry. 12mo, 2 00 + Helm's Principles of Mathematical Chemistry. (Morgan.) 12mo, 1 50 + Hering's Ready Reference Tables (Conversion Factors.) + 16mo, morocco, 2 50 + Herrick's Denatured or Industrial Alcohol. 8vo, 4 00 + Hind's Inorganic Chemistry. 8vo, 3 00 + * Laboratory Manual for Students. 12mo, 1 00 + Holleman's Text-book of Inorganic Chemistry. (Cooper.) 8vo, 2 50 + Text-book of Organic Chemistry. (Walker and Mott.) 8vo, 2 50 + * Laboratory Manual of Organic Chemistry. (Walker.) 12mo, 1 00 + Holley and Ladd's Analysis of Mixed Paints, Color Pigments, + and Varnishes. (In Press.) + Hopkins's Oil-chemists' Handbook. 8vo, 3 00 + Iddings's Rock Minerals. 8vo, 5 00 + Jackson's Directions for Laboratory Work in Physiological + Chemistry. 8vo, 1 25 + Johannsen's Key for the Determination of Rock-forming Minerals + in Thin Sections. (In Press.) + Keep's Cast Iron. 8vo, 2 50 + Ladd's Manual of Quantitative Chemical Analysis. 12mo, 1 00 + Landauer's Spectrum Analysis. (Tingle.) 8vo, 3 00 + * Langworthy and Austen. The Occurrence of Aluminium in + Vegetable Products, Animal Products, and Natural Waters. 8vo, 2 00 + Lassar-Cohn's Application of Some General Reactions to + Investigations in Organic Chemistry. (Tingle.) 12mo, 1 00 + Leach's The Inspection and Analysis of Food with Special + Reference to State Control. 8vo, 7 50 + Loeb's Electrochemistry of Organic Compounds. (Lorenz.) 8vo, 3 00 + Lodge's Notes on Assaying and Metallurgical Laboratory + Experiments. 8vo, 3 00 + Low's Technical Method of Ore Analysis. 8vo, 3 00 + Lunge's Techno-chemical Analysis. (Cohn.) 12mo 1 00 + * McKay and Larsen's Principles and Practice of Butter-making. 8vo, 1 50 + Maire's Modern Pigments and their Vehicles. (In Press.) + Mandel's Handbook for Bio-chemical Laboratory. 12mo, 1 50 + * Martin's Laboratory Guide to Qualitative Analysis with + the Blowpipe. 12mo, 60 + Mason's Water-supply. (Considered Principally from a Sanitary + Standpoint.) 3d Edition, Rewritten. 8vo, 4 00 + Examination of Water. (Chemical and Bacteriological.) 12mo, 1 25 + Matthews's The Textile Fibres. 2d Edition, Rewritten. 8vo, 4 00 + Meyer's Determination of Radicles in Carbon Compounds. + (Tingle.) 12mo, 1 00 + Miller's Manual of Assaying. 12mo, 1 00 + Cyanide Process. 12mo, 1 00 + Minet's Production of Aluminum and its Industrial Use. + (Waldo.) 12mo, 2 50 + Mixter's Elementary Text-book of Chemistry. 12mo, 1 50 + Morgan's An Outline of the Theory of Solutions and its + Results. 12mo, 1 00 + Elements of Physical Chemistry. 12mo, 3 00 + * Physical Chemistry for Electrical Engineers. 12mo, 5 00 + Morse's Calculations used in Cane-sugar Factories. 16mo, morocco, 1 50 + * Muir's History of Chemical Theories and Laws. 8vo, 4 00 + Mulliken's General Method for the Identification of Pure + Organic Compounds. Vol. I. Large 8vo, 5 00 + O'Driscoll's Notes on the Treatment of Gold Ores. 8vo, 2 00 + Ostwald's Conversations on Chemistry. Part One. (Ramsey.) 12mo, 1 50 + " " " " Part Two. (Turnbull.) 12mo, 2 00 + * Palmer's Practical Test Book of Chemistry. 12mo, 1 00 + * Pauli's Physical Chemistry in the Service of Medicine. + (Fischer.) 12mo, 1 25 + * Penfield's Notes on Determinative Mineralogy and + Record of Mineral Tests. 8vo, paper, 50 + Pictet's The Alkaloids and their Chemical Constitution. + (Biddle.) 8vo, 5 00 + Pinner's Introduction to Organic Chemistry. (Austen.) 12mo, 1 50 + Poole's Calorific Power of Fuels. 8vo, 3 00 + Prescott and Winslow's Elements of Water Bacteriology, with + Special Reference to Sanitary Water Analysis. 12mo, 1 25 + * Reisig's Guide to Piece-dyeing. 8vo, 25 00 + Richards and Woodman's Air, Water, and Food from a Sanitary + Standpoint. 8vo, 2 00 + Ricketts and Miller's Notes on Assaying. 8vo, 3 00 + Rideal's Sewage and the Bacterial Purification of Sewage. 8vo, 4 00 + Disinfection and the Preservation of Food. 8vo, 4 00 + Riggs's Elementary Manual for the Chemical Laboratory. 8vo, 1 25 + Robine and Lenglen's Cyanide Industry. (Le Clerc.) 8vo, 4 00 + Ruddiman's Incompatibilities in Prescriptions. 8vo, 2 00 + * Whys in Pharmacy. 12mo, 1 00 + Sabin's Industrial and Artistic Technology of Paints and + Varnish. 8vo, 3 00 + Salkowski's Physiological and Pathological Chemistry. + (Orndorff.) 8vo, 2 50 + Schimpf's Text-book of Volumetric Analysis. 12mo, 2 50 + Essentials of Volumetric Analysis. 12mo, 1 25 + * Qualitative Chemical Analysis. 8vo, 1 25 + Smith's Lecture Notes on Chemistry for Dental Students. 8vo, 2 50 + Spencer's Handbook for Chemists of Beet-sugar Houses. + 16mo, morocco, 3 00 + Handbook for Cane Sugar Manufacturers. 16mo, morocco, 3 00 + Stockbridge's Rocks and Soils. 8vo, 2 50 + * Tillman's Elementary Lessons in Heat. 8vo, 1 50 + * Descriptive General Chemistry. 8vo, 3 00 + Treadwell's Qualitative Analysis. (Hall.) 8vo, 3 00 + Quantitative Analysis. (Hall.) 8vo, 4 00 + Turneaure and Russell's Public Water-supplies. 8vo, 5 00 + Van Deventer's Physical Chemistry for Beginners. (Boltwood.) 12mo, 1 50 + * Walke's Lectures on Explosives. 8vo, 4 00 + Ware's Beet-sugar Manufacture and Refining. Vol. I. Small 8vo, 4 00 + " " " " " Vol. II. Small 8vo, 5 00 + Washington's Manual of the Chemical Analysis of Rocks. 8vo, 2 00 + Weaver's Military Explosives. 8vo, 3 00 + Wehrenfennig's Analysis and Softening of Boiler Feed-Water. 8vo, 4 00 + Wells's Laboratory Guide in Qualitative Chemical Analysis. 8vo, 1 50 + Short Course in Inorganic Qualitative Chemical Analysis + for Engineering Students. 12mo, 1 50 + Text-book of Chemical Arithmetic. 12mo, 1 25 + Whipple's Microscopy of Drinking-water. 8vo, 3 50 + Wilson's Cyanide Processes. 12mo, 1 50 + Chlorination Process. 12mo, 1 50 + Winton's Microscopy of Vegetable Foods. 8vo, 7 50 + Wulling's Elementary Course in Inorganic, Pharmaceutical, + and Medical Chemistry. 12mo, 2 00 + + +CIVIL ENGINEERING. + + +BRIDGES AND ROOFS. HYDRAULICS. MATERIALS OF ENGINEERING. RAILWAY +ENGINEERING. + + Baker's Engineers' Surveying Instruments. 12mo, 3 00 + Bixby's Graphical Computing Table. Paper 19-1/2 x 24-1/4 inches, 25 + Breed and Hosmer's Principles and Practice of Surveying. 8vo, 3 00 + * Burr's Ancient and Modern Engineering and the Isthmian Canal. + 8vo, 3 50 + Comstock's Field Astronomy for Engineers. 8vo, 2 50 + * Corthell's Allowable Pressures on Deep Foundations. 12mo, 1 25 + Crandall's Text-book on Geodesy and Least Squares. 8vo, 3 00 + Davis's Elevation and Stadia Tables. 8vo, 1 00 + Elliott's Engineering for Land Drainage. 12mo, 1 50 + Practical Farm Drainage. 12mo, 1 00 + * Fiebeger's Treatise on Civil Engineering. 8vo, 5 00 + Flemer's Phototopographic Methods and Instruments. 8vo, 5 00 + Folwell's Sewerage. (Designing and Maintenance.) 8vo, 3 00 + Freitag's Architectural Engineering. 2d Edition, Rewritten. 8vo, 3 50 + French and Ives's Stereotomy. 8vo, 2 50 + Goodhue's Municipal Improvements. 12mo, 1 50 + Gore's Elements of Geodesy. 8vo, 2 50 + * Hauch and Rice's Tables of Quantities for Preliminary + Estimates. 12mo, 1 25 + Hayford's Text-book of Geodetic Astronomy. 8vo, 3 00 + Hering's Ready Reference Tables (Conversion Factors). + 16mo, morocco, 2 50 + Howe's Retaining Walls for Earth. 12mo, 1 25 + Hoyt and Grover's River Discharge. 8vo, 2 00 + * Ives's Adjustments of the Engineer's Transit and Level. + 16mo, Bds. 25 + Ives and Hilts's Problems in Surveying. 16mo, morocco, 1 50 + Johnson's (J. B.) Theory and Practice of Surveying. Small 8vo, 4 00 + Johnson's (L. J.) Statics by Algebraic and Graphic Methods. 8vo, 2 00 + Laplace's Philosophical Essay on Probabilities. + (Truscott and Emory.) 12mo, 2 00 + Mahan's Treatise on Civil Engineering. (1873.) (Wood.) 8vo, 5 00 + * Descriptive Geometry. 8vo, 1 50 + Merriman's Elements of Precise Surveying and Geodesy. 8vo, 2 50 + Merriman and Brooks's Handbook for Surveyors. 16mo, morocco, 2 00 + Nugent's Plane Surveying. 8vo, 3 50 + Ogden's Sewer Design. 12mo, 2 00 + Parsons's Disposal of Municipal Refuse. 8vo, 2 00 + Patton's Treatise on Civil Engineering. 8vo half leather, 7 50 + Reed's Topographical Drawing and Sketching. 4to, 5 00 + Rideal's Sewage and the Bacterial Purification of Sewage. 8vo, 4 00 + Riemer's Shaft-sinking under Difficult Conditions. + (Corning and Peele.) 8vo, 3 00 + Siebert and Biggin's Modern Stone-cutting and Masonry. 8vo, 1 50 + Smith's Manual of Topographical Drawing. (McMillan.) 8vo, 2 50 + Sondericker's Graphic Statics, with Applications to + Trusses, Beams, and Arches. 8vo, 2 00 + Taylor and Thompson's Treatise on Concrete, Plain and + Reinforced. 8vo, 5 00 + Tracy's Plane Surveying. 16mo, morocco, 3 00 + * Trautwine's Civil Engineer's Pocket-book. 16mo, morocco, 5 00 + Venable's Garbage Crematories in America. 8vo, 2 00 + Wait's Engineering and Architectural Jurisprudence. 8vo, 6 00 + Sheep, 6 50 + Law of Operations Preliminary to Construction in + Engineering and Architecture. 8vo, 5 00 + Sheep, 5 50 + Law of Contracts. 8vo, 3 00 + Warren's Stereotomy--Problems in Stone-cutting. 8vo, 2 50 + Webb's Problems in the Use and Adjustment of + Engineering Instruments. 16mo, morocco, 1 25 + Wilson's Topographic Surveying. 8vo, 3 50 + + +BRIDGES AND ROOFS. + + Boller's Practical Treatise on the Construction of Iron + Highway Bridges. 8vo, 2 00 + Burr and Falk's Influence Lines for Bridge and Roof + Computations. 8vo, 3 00 + Design and Construction of Metallic Bridges. 8vo, 5 00 + Du Bois's Mechanics of Engineering. Vol. II. Small 4to, 10 00 + Foster's Treatise on Wooden Trestle Bridges. 4to, 5 00 + Fowler's Ordinary Foundations. 8vo, 3 50 + Greene's Roof Trusses. 8vo, 1 25 + Bridge Trusses. 8vo, 2 50 + Arches in Wood, Iron, and Stone. 8vo, 2 50 + Grimm's Secondary Stresses in Bridge Trusses. (In Press.) + Howe's Treatise on Arches. 8vo, 4 00 + Design of Simple Roof-trusses in Wood and Steel. 8vo, 2 00 + Symmetrical Masonry Arches. 8vo, 2 50 + Johnson, Bryan, and Turneaure's Theory and Practice in + the Designing of Modern Framed Structures. Small 4to, 10 00 + Merriman and Jacoby's Text-book on Roofs and Bridges: + Part I. Stresses in Simple Trusses. 8vo, 2 50 + Part II. Graphic Statics. 8vo, 2 50 + Part III. Bridge Design. 8vo, 2 50 + Part IV. Higher Structures. 8vo, 2 50 + Morison's Memphis Bridge. 4to, 10 00 + Waddell's De Pontibus, a Pocket-book for Bridge + Engineers. 16mo, morocco, 2 00 + * Specifications for Steel Bridges. 12mo, 50 + Wright's Designing of Draw-spans. Two parts in one volume. 8vo, 3 50 + + +HYDRAULICS. + + Barnes's Ice Formation. 8vo, 3 00 + Bazin's Experiments upon the Contraction of the Liquid Vein + Issuing from an Orifice. (Trautwine.) 8vo, 2 00 + Bovey's Treatise on Hydraulics. 8vo, 5 00 + Church's Mechanics of Engineering. 8vo, 6 00 + Diagrams of Mean Velocity of Water in Open Channels. paper, 1 50 + Hydraulic Motors. 8vo, 2 00 + Coffin's Graphical Solution of Hydraulic Problems. 16mo, morocco, 2 50 + Flather's Dynamometers, and the Measurement of Power. 12mo, 3 00 + Folwell's Water-supply Engineering. 8vo, 4 00 + Frizell's Water-power. 8vo, 5 00 + Fuertes's Water and Public Health. 12mo, 1 50 + Water-filtration Works. 12mo, 2 50 + Ganguillet and Kutter's General Formula for the Uniform + Flow of Water in Rivers and Other Channels. + (Hering and Trautwine.) 8vo, 4 00 + Hazen's Clean Water and How to Get It. Large 12mo, 1 50 + Filtration of Public Water-supply. 8vo, 3 00 + Hazlehurst's Towers and Tanks for Water-works. 8vo, 2 50 + Herschel's 115 Experiments on the Carrying Capacity of + Large, Riveted, Metal Conduits. 8vo, 2 00 + * Hubbard and Kiersted's Water-works Management and + Maintenance. 8vo, 4 00 + Mason's Water-supply. (Considered Principally from a + Sanitary Standpoint.) 8vo, 4 00 + Merriman's Treatise on Hydraulics. 8vo, 5 00 + * Michie's Elements of Analytical Mechanics. 8vo, 4 00 + Schuyler's Reservoirs for Irrigation, Water-power, and + Domestic Water-supply Large 8vo, 5 00 + * Thomas and Watt's Improvement of Rivers. 4to, 6 00 + Turneaure and Russell's Public Water-supplies. 8vo, 5 00 + Wegmann's Design and Construction of Dams. 5th Edition, + enlarged. 4to, 6 00 + Water-supply of the City of New York from 1658 to 1895. 4to, 10 00 + Whipple's Value of Pure Water. Large 12mo, 1 00 + Williams and Hazen's Hydraulic Tables. 8vo, 1 50 + Wilson's Irrigation Engineering. Small 8vo, 4 00 + Wolff's Windmill as a Prime Mover. 8vo, 3 00 + Wood's Turbines. 8vo, 2 50 + Elements of Analytical Mechanics. 8vo, 3 00 + + +MATERIALS OF ENGINEERING. + + Baker's Treatise on Masonry Construction. 8vo, 5 00 + Roads and Pavements. 8vo, 5 00 + Black's United States Public Works. Oblong 4to, 5 00 + * Bovey's Strength of Materials and Theory of Structures. 8vo, 7 50 + Burr's Elasticity and Resistance of the Materials of + Engineering. 8vo, 7 50 + Byrne's Highway Construction. 8vo, 5 00 + Inspection of the Materials and Workmanship Employed + in Construction. 16mo, 3 00 + Church's Mechanics of Engineering. 8vo, 6 00 + Du Bois's Mechanics of Engineering. Vol. I. Small 4to, 7 50 + * Eckel's Cements, Limes, and Plasters. 8vo, 6 00 + Johnson's Materials of Construction. Large 8vo, 6 00 + Fowler's Ordinary Foundations. 8vo, 3 50 + Graves's Forest Mensuration. 8vo, 4 00 + * Greene's Structural Mechanics. 8vo, 2 50 + Keep's Cast Iron. 8vo, 2 50 + Lanza's Applied Mechanics. 8vo, 7 50 + Martens's Handbook on Testing Materials. (Henning.) 2 vols. 8vo, 7 50 + Maurer's Technical Mechanics. 8vo, 4 00 + Merrill's Stones for Building and Decoration. 8vo, 5 00 + Merriman's Mechanics of Materials. 8vo, 5 00 + * Strength of Materials. 12mo, 1 00 + Metcalf's Steel. A Manual for Steel-users. 12mo, 2 00 + Patron's Practical Treatise on Foundations. 8vo, 5 00 + Richardson's Modern Asphalt Pavements. 8vo, 3 00 + Richey's Handbook for Superintendents of Construction. 16mo, mor., 4 00 + * Ries's Clays; Their Occurrence, Properties, and Uses. 8vo, 5 00 + Rockwell's Roads and Pavements in France. 12mo, 1 25 + Sabin's Industrial and Artistic Technology of Paints and + Varnish. 8vo, 3 00 + * Schwarz's Longleaf Pine in Virgin Forest. 12mo, 1 25 + Smith's Materials of Machines. 12mo, 1 00 + Snow's Principal Species of Wood. 8vo, 3 50 + Spalding's Hydraulic Cement. 12mo, 2 00 + Text-book on Roads and Pavements. 12mo, 2 00 + Taylor and Thompson's Treatise on Concrete, Plain and + Reinforced. 8vo, 5 00 + Thurston's Materials of Engineering. 3 Parts. 8vo, 8 00 + Part I. Non-metallic Materials of Engineering and + Metallurgy. 8vo, 2 00 + Part II. Iron and Steel. 8vo, 3 50 + Part III. A Treatise on Brasses, Bronzes, and Other + Alloys and their Constituents. 8vo, 2 50 + Tillson's Street Pavements and Paving Materials. 8vo, 4 00 + Turneaure and Maurer's Principles of Reinforced Concrete + Construction. 8vo, 3 00 + Waddell's De Pontibus. (A Pocket-book for Bridge + Engineers.) 16mo, mor., 2 00 + * Specifications for Steel Bridges. 12mo, 50 + Wood's (De V.) Treatise on the Resistance of Materials, and + an Appendix on the Preservation of Timber. 8vo, 2 00 + Wood's (De V.) Elements of Analytical Mechanics. 8vo, 3 00 + Wood's (M. P.) Rustless Coatings: Corrosion and Electrolysis + of Iron and Steel. 8vo, 4 00 + + +RAILWAY ENGINEERING. + + Andrew's Handbook for Street Railway Engineers. + 3x5 inches, morocco, 1 25 + Berg's Buildings and Structures of American Railroads. 4to, 5 00 + Brook's Handbook of Street Railroad Location. 16mo, morocco, 1 50 + Butt's Civil Engineer's Field-book. 16mo, morocco, 2 50 + Crandall's Transition Curve. 16mo, morocco, 1 50 + Railway and Other Earthwork Tables. 8vo, 1 50 + Crookett's Methods for Earthwork Computations. (In Press) + Dawson's "Engineering" and Electric Traction + Pocket-book. 16mo, morocco, 5 00 + Dredge's History of the Pennsylvania Railroad: (1879). Paper, 5 00 + Fisher's Table of Cubic Yards. Cardboard, 25 + Godwin's Railroad Engineers' Field-book and Explorers' + Guide. 16mo, mor., 2 50 + Hudson's Tables for Calculating the Cubic Contents of + Excavations and Embankments. 8vo, 1 00 + Molitor and Beard's Manual for Resident Engineers. 16mo, 1 00 + Nagle's Field Manual for Railroad Engineers. 16mo, morocco, 3 00 + Philbrick's Field Manual for Engineers. 16mo, morocco, 3 00 + Raymond's Elements of Railroad Engineering. (In Press.) + Searles's Field Engineering. 16mo, morocco, 3 00 + Railroad Spiral. 16mo, morocco, 1 50 + Taylor's Prismoidal Formulae and Earthwork. 8vo, 1 50 + * Trautwine's Method of Calculating the Cube Contents + of Excavations and Embankments by the Aid of Diagrams. 8vo, 2 00 + The Field Practice of Laying Out Circular Curves + for Railroads. 12mo, morocco, 2 50 + Cross-section Sheet. Paper, 25 + Webb's Railroad Construction. 16mo, morocco, 5 00 + Economics of Railroad Construction. Large 12mo, 2 50 + Wellington's Economic Theory of the Location of Railways. + Small 8vo, 5 00 + + +DRAWING. + + Barr's Kinematics of Machinery. 8vo, 2 50 + * Bartlett's Mechanical Drawing. 8vo, 3 00 + * " " " Abridged Ed. 8vo, 1 50 + Coolidge's Manual of Drawing. 8vo, paper, 1 00 + Coolidge and Freeman's Elements of General Drafting + for Mechanical Engineers. Oblong 4to, 2 50 + Durley's Kinematics of Machines. 8vo, 4 00 + Emch's Introduction to Projective Geometry and its + Applications. 8vo, 2 50 + Hill's Text-book on Shades and Shadows, and Perspective. 8vo, 2 00 + Jamison's Elements of Mechanical Drawing. 8vo, 2 50 + Advanced Mechanical Drawing. 8vo, 2 00 + Jones's Machine Design: + Part I. Kinematics of Machinery. 8vo, 1 50 + Part II. Form, Strength, and Proportions of Parts. 8vo, 3 00 + MacCord's Elements of Descriptive Geometry. 8vo, 3 00 + Kinematics; or, Practical Mechanism. 8vo, 5 00 + Mechanical Drawing. 4to, 4 00 + Velocity Diagrams. 8vo, 1 50 + MacLeod's Descriptive Geometry. Small 8vo, 1 50 + * Mahan's Descriptive Geometry and Stone-cutting. 8vo, 1 50 + Industrial Drawing. (Thompson.) 8vo, 3 50 + Moyer's Descriptive Geometry. 8vo, 2 00 + Reed's Topographical Drawing and Sketching. 4to, 5 00 + Reid's Course in Mechanical Drawing. 8vo, 2 00 + Text-book of Mechanical Drawing and Elementary Machine + Design. 8vo, 3 00 + Robinson's Principles of Mechanism. 8vo, 3 00 + Schwamb and Merrill's Elements of Mechanism. 8vo, 3 00 + Smith's (R. S.) Manual of Topographical Drawing. (McMillan.) 8vo, 2 50 + Smith (A. W.) and Marx's Machine Design. 8vo, 3 00 + * Titsworth's Elements of Mechanical Drawing. Oblong 8vo, 1 25 + Warren's Elements of Plane and Solid Free-hand Geometrical + Drawing. 12mo, 1 00 + Drafting Instruments and Operations. 12mo, 1 25 + Manual of Elementary Projection Drawing. 12mo, 1 50 + Manual of Elementary Problems in the Linear Perspective + of Form and Shadow. 12mo, 1 00 + Plane Problems in Elementary Geometry. 12mo, 1 25 + Elements of Descriptive Geometry, Shadows, and Perspective. + 8vo, 3 50 + General Problems of Shades and Shadows. 8vo, 3 00 + Elements of Machine Construction and Drawing. 8vo, 7 50 + Problems, Theorems, and Examples in Descriptive Geometry. 8vo, 2 50 + Weisbach's Kinematics and Power of Transmission. (Herrmann + and Klein.) 8vo, 5 00 + Whelpley's Practical Instruction in the Art of Letter + Engraving. 12mo, 2 00 + Wilson's (H. M.) Topographic Surveying. 8vo, 3 50 + Wilson's (V. T.) Free-hand Perspective. 8vo, 2 50 + Wilson's (V. T.) Free-hand Lettering. 8vo, 1 00 + Woolf's Elementary Course in Descriptive Geometry. Large 8vo, 3 00 + + +ELECTRICITY AND PHYSICS. + + * Abegg's Theory of Electrolytic Dissociation. (Von Ende.) 12mo, 1 25 + Anthony and Brackett's Text-book of Physics. (Magie.) Small 8vo, 3 00 + Anthony's Lecture-notes on the Theory of Electrical + Measurements. 12mo, 1 00 + Benjamin's History of Electricity. 8vo, 3 00 + Voltaic Cell. 8vo, 3 00 + Betts's Lead Refining and Electrolysis. (In Press.) + Classen's Quantitative Chemical Analysis by Electrolysis. + (Boltwood.) 8vo, 3 00 + * Collins's Manual of Wireless Telegraphy. 12mo, 1 50 + Morocco, 2 00 + Crehore and Squier's Polarizing Photo-chronograph. 8vo, 3 00 + * Danneel's Electrochemistry. (Merriam.) 12mo, 1 25 + Dawson's "Engineering" and Electric Traction + Pocket-book. 16mo, morocco, 5 00 + Dolezalek's Theory of the Lead Accumulator (Storage + Battery). (Von Ende.) 12mo, 2 50 + Duhem's Thermodynamics and Chemistry. (Burgess.) 8vo, 4 00 + Flather's Dynamometers, and the Measurement of Power. 12mo, 3 00 + Gilbert's De Magnete. (Mottelay.) 8vo, 2 50 + Hanchett's Alternating Currents Explained. 12mo, 1 00 + Hering's Ready Reference Tables (Conversion Factors). + 16mo, morocco, 2 50 + Hobart and Ellis's High-speed Dynamo Electric Machinery. (In Press.) + Holman's Precision of Measurements. 8vo, 2 00 + Telescopic Mirror-scale Method, Adjustments, + and Tests. Large 8vo, 75 + Karapetoff's Experimental Electrical Engineering. (In Press.) + Kinzbrunner's Testing of Continuous-current Machines. 8vo, 2 00 + Landauer's Spectrum Analysis. (Tingle.) 8vo, 3 00 + Le Chatelier's High-temperature Measurements. + (Boudouard--Burgess.) 12mo, 3 00 + Loeb's Electrochemistry of Organic Compounds. (Lorenz.) 8vo, 3 00 + * Lyons's Treatise on Electromagnetic Phenomena. + Vols. I. and II. 8vo, each, 6 00 + * Michie's Elements of Wave Motion Relating to + Sound and Light. 8vo, 4 00 + Niaudet's Elementary Treatise on Electric Batteries. + (Fishback.) 12mo, 2 50 + Norris's Introduction to the Study of Electrical Engineering. (In Press.) + * Parshall and Hobart's Electric Machine Design. 4to, half morocco, 12 50 + Reagan's Locomotives: Simple, Compound, and Electric. + New Edition. Large 12mo, 3 50 + * Rosenberg's Electrical Engineering. + (Haldane Gee--Kinzbrunner.) 8vo, 2 00 + Ryan, Norris, and Hoxie's Electrical Machinery. Vol. I. 8vo, 2 50 + Thurston's Stationary Steam-engines. 8vo, 2 50 + * Tillman's Elementary Lessons in Heat. 8vo, 1 50 + Tory and Pitcher's Manual of Laboratory Physics. Small 8vo, 2 00 + Ulke's Modern Electrolytic Copper Refining. 8vo, 3 00 + + +LAW. + + * Davis's Elements of Law. 8vo, 2 50 + * Treatise on the Military Law of United States. 8vo, 7 00 + * Sheep, 7 50 + * Dudley's Military Law and the Procedure + of Courts-martial. Large 12mo, 2 50 + Manual for Courts-martial. 16mo, morocco, 1 50 + Wait's Engineering and Architectural Jurisprudence. 8vo, 6 00 + Sheep, 6 50 + Law of Operations Preliminary to Construction in + Engineering and Architecture. 8vo, 5 00 + Sheep, 5 50 + Law of Contracts. 8vo, 3 00 + Winthrop's Abridgment of Military Law. 12mo, 2 50 + + +MANUFACTURES. + + Bernadou's Smokeless Powder--Nitro-cellulose and Theory of + the Cellulose Molecule. 12mo, 2 50 + Bolland's Iron Founder. 12mo, 2 50 + "The Iron Founder," Supplement. 12mo, 2 50 + Encyclopedia of Founding and Dictionary of Foundry Terms + Used in the Practice of Moulding. 12mo, 3 00 + * Claassen's Beet-sugar Manufacture. (Hall and Rolfe.) 8vo, 3 00 + * Eckel's Cements, Limes, and Plasters. 8vo, 6 00 + Eissler's Modern High Explosives. 8vo, 4 00 + Effront's Enzymes and their Applications. (Prescott.) 8vo, 3 00 + Fitzgerald's Boston Machinist. 12mo, 1 00 + Ford's Boiler Making for Boiler Makers. 18mo, 1 00 + Herrick's Denatured or Industrial Alcohol. 8vo, 4 00 + Holley and Ladd's Analysis of Mixed Paints, Color Pigments, + and Varnishes. (In Press.) + Hopkins's Oil-chemists' Handbook. 8vo, 3 00 + Keep's Cast Iron. 8vo, 2 50 + Leach's The Inspection and Analysis of Food with Special + Reference to State Control. Large 8vo, 7 50 + * McKay and Larsen's Principles and Practice of Butter-making. 8vo, 1 50 + Maire's Modern Pigments and their Vehicles. (In Press.) + Matthews's The Textile Fibres. 2d Edition, Rewritten. 8vo, 4 00 + Metcalf's Steel. A Manual for Steel-users. 12mo, 2 00 + Metcalfe's Cost of Manufactures--And the Administration + of Workshops. 8vo, 5 00 + Meyer's Modern Locomotive Construction. 4to, 10 00 + Morse's Calculations used in Cane-sugar Factories. 16mo, morocco, 1 50 + * Reisig's Guide to Piece-dyeing. 8vo, 25 00 + Rice's Concrete-block Manufacture. 8vo, 2 00 + Sabin's Industrial and Artistic Technology of Paints and + Varnish. 8vo, 3 00 + Smith's Press-working of Metals. 8vo, 3 00 + Spalding's Hydraulic Cement. 12mo, 2 00 + Spencer's Handbook for Chemists of Beet-sugar Houses. + 16mo, morocco, 3 00 + Handbook for Cane Sugar Manufacturers. 16mo, morocco, 3 00 + Taylor and Thompson's Treatise on Concrete, Plain and + Reinforced. 8vo, 5 00 + Thurston's Manual of Steam-boilers, their Designs, + Construction and Operation. 8vo, 5 00 + Ware's Beet-sugar Manufacture and Refining. Vol. I. Small 8vo, 4 00 + " " " " " Vol. II. 8vo, 5 00 + Weaver's Military Explosives. 8vo, 3 00 + West's American Foundry Practice. 12mo, 2 50 + Moulder's Text-book. 12mo, 2 50 + Wolff's Windmill as a Prime Mover. 8vo, 3 00 + Wood's Rustless Coatings: Corrosion and Electrolysis of + Iron and Steel. 8vo, 4 00 + + +MATHEMATICS. + + Baker's Elliptic Functions. 8vo, 1 50 + Briggs's Elements of Plane Analytic Geometry. 12mo, 1 00 + Buchanan's Plane and Spherical Trigonometry. (In Press.) + Compton's Manual of Logarithmic Computations. 12mo, 1 50 + Davis's Introduction to the Logic of Algebra. 8vo, 1 50 + * Dickson's College Algebra. Large 12mo, 1 50 + * Introduction to the Theory of Algebraic Equations. Large 12mo, 1 25 + Emch's Introduction to Projective Geometry and its + Applications. 8vo, 2 50 + Halsted's Elements of Geometry. 8vo, 1 75 + Elementary Synthetic Geometry. 8vo, 1 50 + * Rational Geometry. 12mo, 1 50 + * Johnson's (J. B.) Three-place Logarithmic Tables: + Vest-pocket size paper, 15 + 100 copies for 5 00 + * Mounted on heavy cardboard, 8 x 10 inches, 25 + 10 copies for 2 00 + Johnson's (W. W.) Elementary Treatise on Differential + Calculus. Small 8vo, 3 00 + Elementary Treatise on the Integral Calculus. Small 8vo, 1 50 + Johnson's (W. W.) Curve Tracing in Cartesian Co-ordinates. 12mo, 1 00 + Johnson's (W. W.) Treatise on Ordinary and Partial + Differential Equations. Small 8vo, 3 50 + Johnson's Treatise on the Integral Calculus. Small 8vo, 3 00 + Johnson's (W. W.) Theory of Errors and the Method of + Least Squares. 12mo, 1 50 + * Johnson's (W. W.) Theoretical Mechanics. 12mo, 3 00 + Laplace's Philosophical Essay on Probabilities. + (Truscott and Emory.) 12mo, 2 00 + * Ludlow and Bass. Elements of Trigonometry and Logarithmic + and Other Tables. 8vo, 3 00 + Trigonometry and Tables published separately. Each, 2 00 + * Ludlow's Logarithmic and Trigonometric Tables. 8vo, 1 00 + Manning's Irrational Numbers and their Representation by + Sequences and Series 12mo, 1 25 + Mathematical Monographs. Edited by Mansfield Merriman + and Robert S. Woodward. Octavo, each 1 00 + + No. 1. History of Modern Mathematics, by David Eugene Smith. No. + 2. Synthetic Projective Geometry, by George Bruce Halsted. No. 3. + Determinants, by Laenas Gifford Weld. No. 4. Hyperbolic Functions, + by James McMahon. No. 5. Harmonic Functions, by William E. Byerly. + No. 6. Grassmann's Space Analysis, by Edward W. Hyde. No. 7. + Probability and Theory of Errors, by Robert S. Woodward. No. 8. + Vector Analysis and Quaternions, by Alexander Macfarlane. No. 9. + Differential Equations, by William Woolsey Johnson. No. 10. The + Solution of Equations, by Mansfield Merriman. No. 11. Functions of + a Complex Variable, by Thomas S. Fiske. + + Maurer's Technical Mechanics. 8vo, 4 00 + Merriman's Method of Least Squares. 8vo, 2 00 + Rice and Johnson's Elementary Treatise on the + Differential Calculus. Sm. 8vo, 3 00 + Differential and Integral Calculus. 2 vols. in one. Small 8vo, 3 50 + * Veblen and Lennes's Introduction to the Real + Infinitesimal Analysis of One Variable. 8vo, 2 00 + Wood's Elements of Co-ordinate Geometry. 8vo, 2 00 + Trigonometry: Analytical, Plane, and Spherical. 12mo, 1 00 + + +MECHANICAL ENGINEERING. + +MATERIALS OF ENGINEERING, STEAM-ENGINES AND BOILERS. + + Bacon's Forge Practice. 12mo, 1 50 + Baldwin's Steam Heating for Buildings. 12mo, 2 50 + Barr's Kinematics of Machinery. 8vo, 2 50 + * Bartlett's Mechanical Drawing. 8vo, 3 00 + * " " " Abridged Ed. 8vo, 1 50 + Benjamin's Wrinkles and Recipes. 12mo, 2 00 + Carpenter's Experimental Engineering. 8vo, 6 00 + Heating and Ventilating Buildings. 8vo, 4 00 + Clerk's Gas and Oil Engine. Small 8vo, 4 00 + Coolidge's Manual of Drawing. 8vo, paper, 1 00 + Coolidge and Freeman's Elements of General Drafting + for Mechanical Engineers. Oblong 4to, 2 50 + Cromwell's Treatise on Toothed Gearing. 12mo, 1 50 + Treatise on Belts and Pulleys. 12mo, 1 50 + Durley's Kinematics of Machines. 8vo, 4 00 + Flather's Dynamometers and the Measurement of Power. 12mo, 3 00 + Rope Driving. 12mo, 2 00 + Gill's Gas and Fuel Analysis for Engineers. 12mo, 1 25 + Hall's Car Lubrication. 12mo, 1 00 + Hering's Ready Reference Tables (Conversion Factors). + 16mo, morocco, 2 50 + Hutton's The Gas Engine. 8vo, 5 00 + Jamison's Mechanical Drawing. 8vo, 2 50 + Jones's Machine Design: + Part I. Kinematics of Machinery. 8vo, 1 50 + Part II. Form, Strength, and Proportions of Parts. 8vo, 3 00 + Kent's Mechanical Engineers' Pocket-book. 16mo, morocco, 5 00 + Kerr's Power and Power Transmission. 8vo, 2 00 + Leonard's Machine Shop, Tools, and Methods. 8vo, 4 00 + * Lorenz's Modern Refrigerating Machinery. (Pope, Haven, + and Dean.) 8vo, 4 00 + MacCord's Kinematics; or, Practical Mechanism. 8vo, 5 00 + Mechanical Drawing. 4to, 4 00 + Velocity Diagrams. 8vo, 1 50 + MacFarland's Standard Reduction Factors for Gases. 8vo, 1 50 + Mahan's Industrial Drawing. (Thompson.) 8vo, 3 50 + Poole's Calorific Power of Fuels. 8vo, 3 00 + Reid's Course in Mechanical Drawing. 8vo, 2 00 + Text-book of Mechanical Drawing and Elementary Machine + Design. 8vo, 3 00 + Richards's Compressed Air. 12mo, 1 50 + Robinson's Principles of Mechanism. 8vo, 3 00 + Schwamb and Merrill's Elements of Mechanism. 8vo, 3 00 + Smith's (O.) Press-working of Metals. 8vo, 3 00 + Smith (A. W.) and Marx's Machine Design. 8vo, 3 00 + Thurston's Treatise on Friction and Lost Work in Machinery + and Mill Work. 8vo, 3 00 + Animal as a Machine and Prime Motor, and the Laws of + Energetics. 12mo, 1 00 + Tillson's Complete Automobile Instructor. 16mo, 1 50 + Morocco, 2 00 + Warren's Elements of Machine Construction and Drawing. 8vo, 7 50 + Weisbach's Kinematics and the Power of Transmission. + (Herrmann--Klein.) 8vo, 5 00 + Machinery of Transmission and Governors. (Herrmann--Klein.) + 8vo, 5 00 + Wolff's Windmill as a Prime Mover. 8vo, 3 00 + Wood's Turbines. 8vo, 2 50 + + +MATERIALS OF ENGINEERING. + + * Bovey's Strength of Materials and Theory of Structures. 8vo, 7 50 + Burr's Elasticity and Resistance of the Materials of + Engineering. 6th Edition. Reset. 8vo, 7 50 + Church's Mechanics of Engineering. 8vo, 6 00 + * Greene's Structural Mechanics. 8vo, 2 50 + Johnson's Materials of Construction. 8vo, 6 00 + Keep's Cast Iron. 8vo, 2 50 + Lanza's Applied Mechanics. 8vo, 7 50 + Martens's Handbook on Testing Materials. (Henning.) 8vo, 7 50 + Maurer's Technical Mechanics. 8vo, 4 00 + Merriman's Mechanics of Materials. 8vo, 5 00 + * Strength of Materials 12mo, 1 00 + Metcalf's Steel. A Manual for Steel-users. 12mo, 2 00 + Sabin's Industrial and Artistic Technology of Paints and + Varnish. 8vo, 3 00 + Smith's Materials of Machines. 12mo, 1 00 + Thurston's Materials of Engineering. 3 vols., 8vo, 8 00 + Part II. Iron and Steel. 8vo, 3 50 + Part III. A Treatise on Brasses, Bronzes, and Other + Alloys and their Constituents. 8vo, 2 50 + Wood's (De V.) Treatise on the Resistance of Materials and an + Appendix on the Preservation of Timber. 8vo, 2 00 + Elements of Analytical Mechanics. 8vo, 3 00 + Wood's (M. P.) Rustless Coatings: Corrosion and Electrolysis + of Iron and Steel. 8vo, 4 00 + + +STEAM-ENGINES AND BOILERS. + + Berry's Temperature-entropy Diagram. 12mo, 1 25 + Carnot's Reflections on the Motive Power of Heat. (Thurston.) 12mo, 1 50 + Creighton's Steam-engine and other Heat-motors. 8vo, 5 00 + Dawson's "Engineering" and Electric Traction + Pocket-book. 16mo, mor., 5 00 + Ford's Boiler Making for Boiler Makers. 18mo, 1 00 + Goss's Locomotive Sparks. 8vo, 2 00 + Locomotive Performance. 8vo, 5 00 + Hemenway's Indicator Practice and Steam-engine Economy. 12mo, 2 00 + Hutton's Mechanical Engineering of Power Plants. 8vo, 5 00 + Heat and Heat-engines. 8vo, 5 00 + Kent's Steam boiler Economy. 8vo, 4 00 + Kneass's Practice and Theory of the Injector. 8vo, 1 50 + MacCord's Slide-valves. 8vo, 2 00 + Meyer's Modern Locomotive Construction. 4to, 10 00 + Peabody's Manual of the Steam-engine Indicator. 12mo, 1 50 + Tables of the Properties of Saturated Steam and Other + Vapors. 8vo, 1 00 + Thermodynamics of the Steam-engine and Other Heat-engines. 8vo, 5 00 + Valve-gears for Steam-engines. 8vo, 2 50 + Peabody and Miller's Steam-boilers. 8vo, 4 00 + Pray's Twenty Years with the Indicator. Large 8vo, 2 50 + Pupin's Thermodynamics of Reversible Cycles in Gases and + Saturated Vapors. (Osterberg.) 12mo, 1 25 + Reagan's Locomotives: Simple, Compound, and Electric. + New Edition. Large 12mo, 3 50 + Sinclair's Locomotive Engine Running and Management. 12mo, 2 00 + Smart's Handbook of Engineering Laboratory Practice. 12mo, 2 50 + Snow's Steam-boiler Practice. 8vo, 3 00 + Spangler's Valve-gears. 8vo, 2 50 + Notes on Thermodynamics. 12mo, 1 00 + Spangler, Greene, and Marshall's Elements of + Steam-engineering. 8vo, 3 00 + Thomas's Steam-turbines. 8vo, 3 50 + Thurston's Handy Tables. 8vo, 1 50 + Manual of the Steam-engine. 2 vols., 8vo, 10 00 + Part I. History, Structure, and Theory. 8vo, 6 00 + Part II. Design, Construction, and Operation. 8vo, 6 00 + Handbook of Engine and Boiler Trials, and the Use of the + Indicator and the Prony Brake. 8vo, 5 00 + Stationary Steam-engines. 8vo, 2 50 + Steam-boiler Explosions in Theory and in Practice. 12mo, 1 50 + Manual of Steam-boilers, their Designs, Construction, and + Operation. 8vo, 5 00 + Wehrenfennig's Analysis and Softening of Boiler Feed-water. + (Patterson.) 8vo, 4 00 + Weisbach's Heat, Steam, and Steam-engines. (Du Bois.) 8vo, 5 00 + Whitham's Steam-engine Design. 8vo, 5 00 + Wood's Thermodynamics, Heat Motors, and Refrigerating Machines. + 8vo, 4 00 + + +MECHANICS AND MACHINERY. + + Barr's Kinematics of Machinery. 8vo, 2 50 + * Bovey's Strength of Materials and Theory of Structures. 8vo, 7 50 + Chase's The Art of Pattern-making. 12mo, 2 50 + Church's Mechanics of Engineering. 8vo, 6 00 + Notes and Examples in Mechanics. 8vo, 2 00 + Compton's First Lessons in Metal-working. 12mo, 1 50 + Compton and De Groodt's The Speed Lathe. 12mo, 1 50 + Cromwell's Treatise on Toothed Gearing. 12mo, 1 50 + Treatise on Belts and Pulleys. 12mo, 1 50 + Dana's Text-book of Elementary Mechanics for Colleges and + Schools. 12mo, 1 50 + Dingey's Machinery Pattern Making. 12mo, 2 00 + Dredge's Record of the Transportation Exhibits Building of + the World's Columbian Exposition of 1893. 4to, half morocco, 5 00 + Du Bois's Elementary Principles of Mechanics: + Vol. I. Kinematics. 8vo, 3 50 + Vol. II. Statics. 8vo, 4 00 + Mechanics of Engineering. Vol. I. Small 4to, 7 50 + Vol. II. Small 4to, 10 00 + Durley's Kinematics of Machines. 8vo, 4 00 + Fitzgerald's Boston Machinist. 16mo, 1 00 + Flather's Dynamometers, and the Measurement of Power. 12mo, 3 00 + Rope Driving. 12mo, 2 00 + Goss's Locomotive Sparks. 8vo, 2 00 + Locomotive Performance. 8vo, 5 00 + * Greene's Structural Mechanics. 8vo, 2 50 + Hall's Car Lubrication. 12mo, 1 00 + Hobart and Ellis's High-speed Dynamo Electric Machinery. (In Press.) + Holly's Art of Saw Filing. 18mo, 75 + James's Kinematics of a Point and the Rational Mechanics + of a Particle. Small 8vo, 2 00 + * Johnson's (W. W.) Theoretical Mechanics. 12mo, 3 00 + Johnson's (L. J.) Statics by Graphic and Algebraic Methods. 8vo, 2 00 + Jones's Machine Design: + Part I. Kinematics of Machinery. 8vo, 1 50 + Part II. Form, Strength, and Proportions of Parts. 8vo, 3 00 + Kerr's Power and Power Transmission. 8vo, 2 00 + Lanza's Applied Mechanics. 8vo, 7 50 + Leonard's Machine Shop, Tools, and Methods. 8vo, 4 00 + * Lorenz's Modern Refrigerating Machinery. (Pope, Haven, + and Dean.) 8vo, 4 00 + MacCord's Kinematics; or, Practical Mechanism. 8vo, 5 00 + Velocity Diagrams. 8vo, 1 50 + * Martin's Text Book on Mechanics, Vol. 1, Statics. 12mo, 1 25 + * Vol. 2, Kinematics and + Kinetics. 12mo, 1 50 + Maurer's Technical Mechanics. 8vo, 4 00 + Merriman's Mechanics of Materials. 8vo, 5 00 + * Elements of Mechanics. 12mo, 1 00 + * Michie's Elements of Analytical Mechanics. 8vo, 4 00 + * Parshall and Hobart's Electric Machine Design. 4to, half morocco, 12 50 + Reagan's Locomotives: Simple, Compound, and Electric. + New Edition. Large 12mo, 3 50 + Reid's Course in Mechanical Drawing. 8vo, 2 00 + Text-book of Mechanical Drawing and Elementary Machine + Design. 8vo, 3 00 + Richards's Compressed Air. 12mo, 1 50 + Robinson's Principles of Mechanism. 8vo, 3 00 + Ryan, Norris, and Hoxie's Electrical Machinery. Vol. I. 8vo, 2 50 + Sanborn's Mechanics: Problems. Large 12mo, 1 50 + Schwamb and Merrill's Elements of Mechanism. 8vo, 3 00 + Sinclair's Locomotive-engine Running and Management. 12mo, 2 00 + Smith's (O.) Press-working of Metals. 8vo, 3 00 + Smith's (A. W.) Materials of Machines. 12mo, 1 00 + Smith (A. W.) and Marx's Machine Design. 8vo, 3 00 + Sorel's Carbureting and Combustion of Alcohol Engines. + (Woodward and Preston.) Large 8vo, 3 00 + Spangler, Greene, and Marshall's Elements of Steam-engineering. + 8vo, 3 00 + Thurston's Treatise on Friction and Lost Work in Machinery and + Mill Work. 8vo, 3 00 + Animal as a Machine and Prime Motor, and the Laws of + Energetics. 12mo, 1 00 + Tillson's Complete Automobile Instructor. 16mo, 1 50 + Morocco, 2 00 + Warren's Elements of Machine Construction and Drawing. 8vo, 7 50 + Weisbach's Kinematics and Power of Transmission. + (Herrmann--Klein.) 8vo, 5 00 + Machinery of Transmission and Governors. (Herrmann--Klein.) + 8vo, 5 00 + Wood's Elements of Analytical Mechanics. 8vo, 3 00 + Principles of Elementary Mechanics. 12mo, 1 25 + Turbines. 8vo, 2 50 + The World's Columbian Exposition of 1893. 4to, 1 00 + + +MEDICAL. + + * Bolduan's Immune Sera. 12mo, 1 50 + De Fursac's Manual of Psychiatry. (Rosanoff and + Collins.) Large 12mo, 2 50 + Ehrlich's Collected Studies on Immunity. (Bolduan.) 8vo, 6 00 + * Fischer's Physiology of Alimentation. Large 12mo, cloth, 2 00 + Hammarsten's Text-book on Physiological Chemistry. (Mandel.) 8vo, 4 00 + Lassar-Cohn's Practical Urinary Analysis. (Lorenz.) 12mo, 1 00 + * Pauli's Physical Chemistry in the Service of Medicine. + (Fischer.) 12mo, 1 25 + * Pozzi-Escot's The Toxins and Venoms and their Antibodies. + (Cohn.) 12mo, 1 00 + Rostoski's Serum Diagnosis. (Bolduan.) 12mo, 1 00 + Salkowski's Physiological and Pathological Chemistry. + (Orndorff.) 8vo, 2 50 + * Satterlee's Outlines of Human Embryology. 12mo, 1 25 + Steel's Treatise on the Diseases of the Dog. 8vo, 3 50 + Von Behring's Suppression of Tuberculosis. (Bolduan.) 12mo, 1 00 + Woodhull's Notes on Military Hygiene. 16mo, 1 50 + * Personal Hygiene. 12mo, 1 00 + Wulling's An Elementary Course in Inorganic Pharmaceutical + and Medical Chemistry. 12mo, 2 00 + + +METALLURGY. + + Betts's Lead Refining by Electrolysis. (In Press.) + Egleston's Metallurgy of Silver, Gold, and Mercury. + Vol. I. Silver. 8vo, 7 50 + Vol. II. Gold and Mercury. 8vo, 7 50 + Goesel's Minerals and Metals: A Reference Book. 16mo, mor. 3 00 + * Iles's Lead-smelting. 12mo, 2 50 + Keep's Cast Iron. 8vo, 2 50 + Kunhardt's Practice of Ore Dressing in Europe. 8vo, 1 50 + Le Chatelier's High-temperature Measurements. + (Boudouard--Burgess.) 12mo, 3 00 + Metcalf's Steel. A Manual for Steel-users. 12mo, 2 00 + Miller's Cyanide Process. 12mo, 1 00 + Minet's Production of Aluminum and its Industrial Use. + (Waldo.) 12mo, 2 50 + Robine and Lenglen's Cyanide Industry. (Le Clerc.) 8vo, 4 00 + Smith's Materials of Machines. 12mo, 1 00 + Thurston's Materials of Engineering. In Three Parts. 8vo, 8 00 + Part II. Iron and Steel. 8vo, 3 50 + Part III. A Treatise on Brasses, Bronzes, and Other Alloys + and their Constituents. 8vo, 2 50 + Ulke's Modern Electrolytic Copper Refining. 8vo, 3 00 + + +MINERALOGY. + + Barringer's Description of Minerals of Commercial + Value. Oblong, morocco, 2 50 + Boyd's Resources of Southwest Virginia. 8vo, 3 00 + Boyd's Map of Southwest Virginia. Pocket-book form. 2 00 + * Browning's Introduction to the Rarer Elements. 8vo, 1 50 + Brush's Manual of Determinative Mineralogy. (Penfield.) 8vo, 4 00 + Chester's Catalogue of Minerals. 8vo, paper, 1 00 + Cloth, 1 25 + Dictionary of the Names of Minerals. 8vo, 3 50 + Dana's System of Mineralogy. Large 8vo, half leather, 12 50 + First Appendix to Dana's New "System of Mineralogy." Large 8vo, 1 00 + Text-book of Mineralogy. 8vo, 4 00 + Minerals and How to Study Them. 12mo, 1 50 + Catalogue of American Localities of Minerals. Large 8vo, 1 00 + Manual of Mineralogy and Petrography. 12mo, 2 00 + Douglas's Untechnical Addresses on Technical Subjects. 12mo, 1 00 + Eakle's Mineral Tables. 8vo, 1 25 + Egleston's Catalogue of Minerals and Synonyms. 8vo, 2 50 + Goesel's Minerals and Metals: A Reference Book. 16mo, mor., 3 00 + Groth's Introduction to Chemical Crystallography (Marshall.) 12mo, 1 25 + Iddings's Rock Minerals. 8vo, 5 00 + Johannsen's Key for the Determination of Rock-forming Minerals + in Thin Sections. (In Press.) + * Martin's Laboratory Guide to Qualitative Analysis with the + Blowpipe. 12mo, 60 + Merrill's Non-metallic Minerals. Their Occurrence and Uses. 8vo, 4 00 + Stones for Building and Decoration. 8vo, 5 00 + * Penfield's Notes on Determinative Mineralogy and + Record of Mineral Tests. 8vo, paper, 50 + Tables of Minerals. 8vo, 1 00 + * Richards's Synopsis of Mineral Characters 12mo, morocco, 1 25 + * Ries's Clays. Their Occurrence, Properties, and Uses. 8vo, 5 00 + Rosenbusch's Microscopical Physiography of the Rock-making + Minerals. (Iddings.) 8vo, 5 00 + * Tillman's Text-book of Important Minerals and Rocks. 8vo, 2 00 + + +MINING. + + Beard's Mine Gases and Explosions. (In Press.) + Boyd's Resources of Southwest Virginia. 8vo, 3 00 + Map of Southwest Virginia. Pocket-book form, 2 00 + Douglas's Untechnical Addresses on Technical Subjects. 12mo, 1 00 + Eissler's Modern High Explosives. 8vo, 4 00 + Goesel's Minerals and Metals; A Reference Book. 16mo, mor., 3 00 + Goodyear's Coal-mines of the Western Coast of the + United States. 12mo, 2 50 + Ihlseng's Manual of Mining. 8vo, 5 00 + * Iles's Lead-smelting. 12mo, 2 50 + Kunhardt's Practice of Ore Dressing in Europe. 8vo, 1 50 + Miller's Cyanide Process. 12mo, 1 00 + O'Driscoll's Notes on the Treatment of Gold Ores. 8vo, 2 00 + Robine and Lenglen's Cyanide Industry. (Le Clerc.) 8vo, 4 00 + Weaver's Military Explosives. 8vo, 3 00 + Wilson's Cyanide Processes. 12mo, 1 50 + Chlorination Process. 12mo, 1 50 + Hydraulic and Placer Mining. 2d edition, rewritten. 12mo, 2 50 + Treatise on Practical and Theoretical Mine Ventilation. 12mo, 1 25 + + +SANITARY SCIENCE. + + Bashore's Sanitation of a Country House. 12mo, 1 00 + * Outlines of Practical Sanitation. 12mo, 1 25 + Folwell's Sewerage. (Designing, Construction, and Maintenance.) + 8vo, 3 00 + Water-supply Engineering. 8vo, 4 00 + Fowler's Sewage Works Analyses. 12mo, 2 00 + Fuertes's Water and Public Health. 12mo, 1 50 + Water-filtration Works. 12mo, 2 50 + Gerhard's Guide to Sanitary House-inspection. 16mo, 1 00 + Sanitation of Public Buildings. 12mo, 1 50 + Hazen's Filtration of Public Water-supplies. 8vo, 3 00 + Leach's The Inspection and Analysis of Food with Special + Reference to State Control. 8vo, 7 50 + Mason's Water-supply. (Considered principally from a Sanitary + Standpoint) 8vo, 4 00 + Examination of Water. (Chemical and Bacteriological.) 12mo, 1 25 + * Merriman's Elements of Sanitary Engineering. 8vo, 2 00 + Ogden's Sewer Design. 12mo, 2 00 + Prescott and Winslow's Elements of Water Bacteriology, with + Special Reference to Sanitary Water Analysis. 12mo, 1 25 + * Price's Handbook on Sanitation. 12mo, 1 50 + Richards's Cost of Food. A Study in Dietaries. 12mo, 1 00 + Cost of Living as Modified by Sanitary Science. 12mo, 1 00 + Cost of Shelter. 12mo, 1 00 + Richards and Woodman's Air. Water, and Food from a Sanitary + Standpoint. 8vo, 2 00 + * Richards and Williams's The Dietary Computer. 8vo, 1 50 + Rideal's Sewage and Bacterial Purification of Sewage. 8vo, 4 00 + Disinfection and the Preservation of Food. 8vo, 4 00 + Turneaure and Russell's Public Water-supplies. 8vo, 5 00 + Von Behring's Suppression of Tuberculosis. (Bolduan.) 12mo, 1 00 + Whipple's Microscopy of Drinking-water. 8vo, 3 50 + Wilson's Air Conditioning. (In Press.) + Winton's Microscopy of Vegetable Foods. 8vo, 7 50 + Woodhull's Notes on Military Hygiene. 16mo, 1 50 + * Personal Hygiene. 12mo, 1 00 + + +MISCELLANEOUS. + + Association of State and National Food and Dairy Departments + (Interstate Pure Food Commission): + Tenth Annual Convention Held at Hartford, + July 17-20, 1906. 8vo, 3 00 + Eleventh Annual Convention, Held at Jamestown + Tri-Centennial Exposition, July 16-19, 1907. (In Press.) + Emmons's Geological Guide-book of the Rocky Mountain Excursion + of the International Congress of Geologists. Large 8vo, 1 50 + Ferrel's Popular Treatise on the Winds. 8vo, 4 00 + Gannett's Statistical Abstract of the World. 24mo, 75 + Gerhard's The Modern Bath and Bath-houses. (In Press.) + Haines's American Railway Management. 12mo, 2 50 + Ricketts's History of Rensselaer Polytechnic Institute, + 1824-1894. Small 8vo, 3 00 + Rotherham's Emphasized New Testament. Large 8vo, 2 00 + Standage's Decorative Treatment of Wood, Glass, Metal, etc. (In Press.) + The World's Columbian Exposition of 1893. 4to, 1 00 + Winslow's Elements of Applied Microscopy. 12mo, 1 50 + + +HEBREW AND CHALDEE TEXT-BOOKS. + + Green's Elementary Hebrew Grammar. 12mo, 1 25 + Hebrew Chrestomathy. 8vo, 2 00 + Gesenius's Hebrew and Chaldee Lexicon to the Old Testament + Scriptures. (Tregelles.) Small 4to, half morocco, 5 00 + Letteris's Hebrew Bible. 8vo, 2 25 + + + +--------------------------------------------------------------+ + | Transcriber's Notes | + | | + | The following inconsistencies were kept: | + | | + | Aluminum -- Aluminium | + | canceled -- cancelled | + | Cubit's Gap -- CUBITS GAP | + | Encyclopaedia -- Encyclopedia | + | Feed-water -- Feed-Water | + | Light-House -- lighthouse | + | sea-weed -- seaweed | + | | + | Punctuation has been corrected without explicit notice. | + | The following changes have been made (c. = catalogue page): | + | | + | p. vii "Nordenskiold" changed to "Nordenskioeld" | + | p. 9 "alsoo" changed to "also". | + | p. 114 "United States Court Survey" changed to | + | "United States Coast Survey". | + | p. 132 "22 deg..5" changed to "22.5 deg.". | + | c. 1 "Rivetee" changed to "Rivetee". | + | c. 3 "Metcalf's" changed to "Metcalfe's". | + | c. 5 "Matthew's" changed to "Matthews's". | + | c. 10 "Hermann" changed to "Herrmann". | + | c. 12 "Maunal" changed to "Manual". | + | c. 14 "Richard's" changed to "Richards's". | + | c. 15 "Wehrenfenning's" changed to "Wehrenfennig's". | + | c. 18 "Virignia" changed to "Virginia". | + +--------------------------------------------------------------+ + + + + + + + +End of the Project Gutenberg EBook of Nautical Charts, by G. R. Putnam + +*** END OF THIS PROJECT GUTENBERG EBOOK NAUTICAL CHARTS *** + +***** This file should be named 44175.txt or 44175.zip ***** +This and all associated files of various formats will be found in: + http://www.gutenberg.org/4/4/1/7/44175/ + +Produced by Chris Curnow, Peter Becker and the Online +Distributed Proofreading Team at http://www.pgdp.net (This +file was produced from images generously made available +by The Internet Archive) + + +Updated editions will replace the previous one--the old editions +will be renamed. + +Creating the works from public domain print editions means that no +one owns a United States copyright in these works, so the Foundation +(and you!) can copy and distribute it in the United States without +permission and without paying copyright royalties. Special rules, +set forth in the General Terms of Use part of this license, apply to +copying and distributing Project Gutenberg-tm electronic works to +protect the PROJECT GUTENBERG-tm concept and trademark. Project +Gutenberg is a registered trademark, and may not be used if you +charge for the eBooks, unless you receive specific permission. If you +do not charge anything for copies of this eBook, complying with the +rules is very easy. You may use this eBook for nearly any purpose +such as creation of derivative works, reports, performances and +research. They may be modified and printed and given away--you may do +practically ANYTHING with public domain eBooks. Redistribution is +subject to the trademark license, especially commercial +redistribution. + + + +*** START: FULL LICENSE *** + +THE FULL PROJECT GUTENBERG LICENSE +PLEASE READ THIS BEFORE YOU DISTRIBUTE OR USE THIS WORK + +To protect the Project Gutenberg-tm mission of promoting the free +distribution of electronic works, by using or distributing this work +(or any other work associated in any way with the phrase "Project +Gutenberg"), you agree to comply with all the terms of the Full Project +Gutenberg-tm License available with this file or online at + www.gutenberg.org/license. + + +Section 1. General Terms of Use and Redistributing Project Gutenberg-tm +electronic works + +1.A. By reading or using any part of this Project Gutenberg-tm +electronic work, you indicate that you have read, understand, agree to +and accept all the terms of this license and intellectual property +(trademark/copyright) agreement. If you do not agree to abide by all +the terms of this agreement, you must cease using and return or destroy +all copies of Project Gutenberg-tm electronic works in your possession. +If you paid a fee for obtaining a copy of or access to a Project +Gutenberg-tm electronic work and you do not agree to be bound by the +terms of this agreement, you may obtain a refund from the person or +entity to whom you paid the fee as set forth in paragraph 1.E.8. + +1.B. "Project Gutenberg" is a registered trademark. It may only be +used on or associated in any way with an electronic work by people who +agree to be bound by the terms of this agreement. There are a few +things that you can do with most Project Gutenberg-tm electronic works +even without complying with the full terms of this agreement. See +paragraph 1.C below. There are a lot of things you can do with Project +Gutenberg-tm electronic works if you follow the terms of this agreement +and help preserve free future access to Project Gutenberg-tm electronic +works. See paragraph 1.E below. + +1.C. The Project Gutenberg Literary Archive Foundation ("the Foundation" +or PGLAF), owns a compilation copyright in the collection of Project +Gutenberg-tm electronic works. Nearly all the individual works in the +collection are in the public domain in the United States. If an +individual work is in the public domain in the United States and you are +located in the United States, we do not claim a right to prevent you from +copying, distributing, performing, displaying or creating derivative +works based on the work as long as all references to Project Gutenberg +are removed. Of course, we hope that you will support the Project +Gutenberg-tm mission of promoting free access to electronic works by +freely sharing Project Gutenberg-tm works in compliance with the terms of +this agreement for keeping the Project Gutenberg-tm name associated with +the work. You can easily comply with the terms of this agreement by +keeping this work in the same format with its attached full Project +Gutenberg-tm License when you share it without charge with others. + +1.D. The copyright laws of the place where you are located also govern +what you can do with this work. Copyright laws in most countries are in +a constant state of change. If you are outside the United States, check +the laws of your country in addition to the terms of this agreement +before downloading, copying, displaying, performing, distributing or +creating derivative works based on this work or any other Project +Gutenberg-tm work. The Foundation makes no representations concerning +the copyright status of any work in any country outside the United +States. + +1.E. Unless you have removed all references to Project Gutenberg: + +1.E.1. The following sentence, with active links to, or other immediate +access to, the full Project Gutenberg-tm License must appear prominently +whenever any copy of a Project Gutenberg-tm work (any work on which the +phrase "Project Gutenberg" appears, or with which the phrase "Project +Gutenberg" is associated) is accessed, displayed, performed, viewed, +copied or distributed: + +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 + +1.E.2. If an individual Project Gutenberg-tm electronic work is derived +from the public domain (does not contain a notice indicating that it is +posted with permission of the copyright holder), the work can be copied +and distributed to anyone in the United States without paying any fees +or charges. If you are redistributing or providing access to a work +with the phrase "Project Gutenberg" associated with or appearing on the +work, you must comply either with the requirements of paragraphs 1.E.1 +through 1.E.7 or obtain permission for the use of the work and the +Project Gutenberg-tm trademark as set forth in paragraphs 1.E.8 or +1.E.9. + +1.E.3. If an individual Project Gutenberg-tm electronic work is posted +with the permission of the copyright holder, your use and distribution +must comply with both paragraphs 1.E.1 through 1.E.7 and any additional +terms imposed by the copyright holder. Additional terms will be linked +to the Project Gutenberg-tm License for all works posted with the +permission of the copyright holder found at the beginning of this work. + +1.E.4. Do not unlink or detach or remove the full Project Gutenberg-tm +License terms from this work, or any files containing a part of this +work or any other work associated with Project Gutenberg-tm. + +1.E.5. Do not copy, display, perform, distribute or redistribute this +electronic work, or any part of this electronic work, without +prominently displaying the sentence set forth in paragraph 1.E.1 with +active links or immediate access to the full terms of the Project +Gutenberg-tm License. + +1.E.6. You may convert to and distribute this work in any binary, +compressed, marked up, nonproprietary or proprietary form, including any +word processing or hypertext form. However, if you provide access to or +distribute copies of a Project Gutenberg-tm work in a format other than +"Plain Vanilla ASCII" or other format used in the official version +posted on the official Project Gutenberg-tm web site (www.gutenberg.org), +you must, at no additional cost, fee or expense to the user, provide a +copy, a means of exporting a copy, or a means of obtaining a copy upon +request, of the work in its original "Plain Vanilla ASCII" or other +form. Any alternate format must include the full Project Gutenberg-tm +License as specified in paragraph 1.E.1. + +1.E.7. Do not charge a fee for access to, viewing, displaying, +performing, copying or distributing any Project Gutenberg-tm works +unless you comply with paragraph 1.E.8 or 1.E.9. + +1.E.8. You may charge a reasonable fee for copies of or providing +access to or distributing Project Gutenberg-tm electronic works provided +that + +- You pay a royalty fee of 20% of the gross profits you derive from + the use of Project Gutenberg-tm works calculated using the method + you already use to calculate your applicable taxes. The fee is + owed to the owner of the Project Gutenberg-tm trademark, but he + has agreed to donate royalties under this paragraph to the + Project Gutenberg Literary Archive Foundation. Royalty payments + must be paid within 60 days following each date on which you + prepare (or are legally required to prepare) your periodic tax + returns. Royalty payments should be clearly marked as such and + sent to the Project Gutenberg Literary Archive Foundation at the + address specified in Section 4, "Information about donations to + the Project Gutenberg Literary Archive Foundation." + +- You provide a full refund of any money paid by a user who notifies + you in writing (or by e-mail) within 30 days of receipt that s/he + does not agree to the terms of the full Project Gutenberg-tm + License. You must require such a user to return or + destroy all copies of the works possessed in a physical medium + and discontinue all use of and all access to other copies of + Project Gutenberg-tm works. + +- You provide, in accordance with paragraph 1.F.3, a full refund of any + money paid for a work or a replacement copy, if a defect in the + electronic work is discovered and reported to you within 90 days + of receipt of the work. + +- You comply with all other terms of this agreement for free + distribution of Project Gutenberg-tm works. + +1.E.9. If you wish to charge a fee or distribute a Project Gutenberg-tm +electronic work or group of works on different terms than are set +forth in this agreement, you must obtain permission in writing from +both the Project Gutenberg Literary Archive Foundation and Michael +Hart, the owner of the Project Gutenberg-tm trademark. Contact the +Foundation as set forth in Section 3 below. + +1.F. + +1.F.1. Project Gutenberg volunteers and employees expend considerable +effort to identify, do copyright research on, transcribe and proofread +public domain works in creating the Project Gutenberg-tm +collection. Despite these efforts, Project Gutenberg-tm electronic +works, and the medium on which they may be stored, may contain +"Defects," such as, but not limited to, incomplete, inaccurate or +corrupt data, transcription errors, a copyright or other intellectual +property infringement, a defective or damaged disk or other medium, a +computer virus, or computer codes that damage or cannot be read by +your equipment. + +1.F.2. LIMITED WARRANTY, DISCLAIMER OF DAMAGES - Except for the "Right +of Replacement or Refund" described in paragraph 1.F.3, the Project +Gutenberg Literary Archive Foundation, the owner of the Project +Gutenberg-tm trademark, and any other party distributing a Project +Gutenberg-tm electronic work under this agreement, disclaim all +liability to you for damages, costs and expenses, including legal +fees. YOU AGREE THAT YOU HAVE NO REMEDIES FOR NEGLIGENCE, STRICT +LIABILITY, BREACH OF WARRANTY OR BREACH OF CONTRACT EXCEPT THOSE +PROVIDED IN PARAGRAPH 1.F.3. YOU AGREE THAT THE FOUNDATION, THE +TRADEMARK OWNER, AND ANY DISTRIBUTOR UNDER THIS AGREEMENT WILL NOT BE +LIABLE TO YOU FOR ACTUAL, DIRECT, INDIRECT, CONSEQUENTIAL, PUNITIVE OR +INCIDENTAL DAMAGES EVEN IF YOU GIVE NOTICE OF THE POSSIBILITY OF SUCH +DAMAGE. + +1.F.3. LIMITED RIGHT OF REPLACEMENT OR REFUND - If you discover a +defect in this electronic work within 90 days of receiving it, you can +receive a refund of the money (if any) you paid for it by sending a +written explanation to the person you received the work from. If you +received the work on a physical medium, you must return the medium with +your written explanation. The person or entity that provided you with +the defective work may elect to provide a replacement copy in lieu of a +refund. If you received the work electronically, the person or entity +providing it to you may choose to give you a second opportunity to +receive the work electronically in lieu of a refund. If the second copy +is also defective, you may demand a refund in writing without further +opportunities to fix the problem. + +1.F.4. Except for the limited right of replacement or refund set forth +in paragraph 1.F.3, this work is provided to you 'AS-IS', WITH NO OTHER +WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO +WARRANTIES OF MERCHANTABILITY OR FITNESS FOR ANY PURPOSE. + +1.F.5. Some states do not allow disclaimers of certain implied +warranties or the exclusion or limitation of certain types of damages. +If any disclaimer or limitation set forth in this agreement violates the +law of the state applicable to this agreement, the agreement shall be +interpreted to make the maximum disclaimer or limitation permitted by +the applicable state law. The invalidity or unenforceability of any +provision of this agreement shall not void the remaining provisions. + +1.F.6. INDEMNITY - You agree to indemnify and hold the Foundation, the +trademark owner, any agent or employee of the Foundation, anyone +providing copies of Project Gutenberg-tm electronic works in accordance +with this agreement, and any volunteers associated with the production, +promotion and distribution of Project Gutenberg-tm electronic works, +harmless from all liability, costs and expenses, including legal fees, +that arise directly or indirectly from any of the following which you do +or cause to occur: (a) distribution of this or any Project Gutenberg-tm +work, (b) alteration, modification, or additions or deletions to any +Project Gutenberg-tm work, and (c) any Defect you cause. + + +Section 2. Information about the Mission of Project Gutenberg-tm + +Project Gutenberg-tm is synonymous with the free distribution of +electronic works in formats readable by the widest variety of computers +including obsolete, old, middle-aged and new computers. It exists +because of the efforts of hundreds of volunteers and donations from +people in all walks of life. + +Volunteers and financial support to provide volunteers with the +assistance they need are critical to reaching Project Gutenberg-tm's +goals and ensuring that the Project Gutenberg-tm collection will +remain freely available for generations to come. In 2001, the Project +Gutenberg Literary Archive Foundation was created to provide a secure +and permanent future for Project Gutenberg-tm and future generations. +To learn more about the Project Gutenberg Literary Archive Foundation +and how your efforts and donations can help, see Sections 3 and 4 +and the Foundation information page at www.gutenberg.org + + +Section 3. Information about the Project Gutenberg Literary Archive +Foundation + +The Project Gutenberg Literary Archive Foundation is a non profit +501(c)(3) educational corporation organized under the laws of the +state of Mississippi and granted tax exempt status by the Internal +Revenue Service. The Foundation's EIN or federal tax identification +number is 64-6221541. Contributions to the Project Gutenberg +Literary Archive Foundation are tax deductible to the full extent +permitted by U.S. federal laws and your state's laws. + +The Foundation's principal office is located at 4557 Melan Dr. S. +Fairbanks, AK, 99712., but its volunteers and employees are scattered +throughout numerous locations. Its business office is located at 809 +North 1500 West, Salt Lake City, UT 84116, (801) 596-1887. Email +contact links and up to date contact information can be found at the +Foundation's web site and official page at www.gutenberg.org/contact + +For additional contact information: + Dr. Gregory B. Newby + Chief Executive and Director + gbnewby@pglaf.org + +Section 4. Information about Donations to the Project Gutenberg +Literary Archive Foundation + +Project Gutenberg-tm depends upon and cannot survive without wide +spread public support and donations to carry out its mission of +increasing the number of public domain and licensed works that can be +freely distributed in machine readable form accessible by the widest +array of equipment including outdated equipment. Many small donations +($1 to $5,000) are particularly important to maintaining tax exempt +status with the IRS. + +The Foundation is committed to complying with the laws regulating +charities and charitable donations in all 50 states of the United +States. Compliance requirements are not uniform and it takes a +considerable effort, much paperwork and many fees to meet and keep up +with these requirements. We do not solicit donations in locations +where we have not received written confirmation of compliance. To +SEND DONATIONS or determine the status of compliance for any +particular state visit www.gutenberg.org/donate + +While we cannot and do not solicit contributions from states where we +have not met the solicitation requirements, we know of no prohibition +against accepting unsolicited donations from donors in such states who +approach us with offers to donate. + +International donations are gratefully accepted, but we cannot make +any statements concerning tax treatment of donations received from +outside the United States. U.S. laws alone swamp our small staff. + +Please check the Project Gutenberg Web pages for current donation +methods and addresses. Donations are accepted in a number of other +ways including checks, online payments and credit card donations. +To donate, please visit: www.gutenberg.org/donate + + +Section 5. General Information About Project Gutenberg-tm electronic +works. + +Professor Michael S. Hart was the originator of the Project Gutenberg-tm +concept of a library of electronic works that could be freely shared +with anyone. For forty years, he produced and distributed Project +Gutenberg-tm eBooks with only a loose network of volunteer support. + +Project Gutenberg-tm eBooks are often created from several printed +editions, all of which are confirmed as Public Domain in the U.S. +unless a copyright notice is included. Thus, we do not necessarily +keep eBooks in compliance with any particular paper edition. + +Most people start at our Web site which has the main PG search facility: + + www.gutenberg.org + +This Web site includes information about Project Gutenberg-tm, +including how to make donations to the Project Gutenberg Literary +Archive Foundation, how to help produce our new eBooks, and how to +subscribe to our email newsletter to hear about new eBooks. + |