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diff --git a/167-0.txt b/167-0.txt new file mode 100644 index 0000000..796e45b --- /dev/null +++ b/167-0.txt @@ -0,0 +1,4997 @@ +The Project Gutenberg EBook of American Handbook of the Daguerrotype, by Samuel D. Humphrey + +This eBook is for the use of anyone anywhere in the United States and most +other parts of the world 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. If you are not located in the United States, you'll have +to check the laws of the country where you are located before using this ebook. + +Title: American Handbook of the Daguerrotype + +Author: Samuel D. Humphrey + +Release Date: September, 1994 [EBook #167] +[Most recently updated: July 3, 2020] + +Language: English + +Character set encoding: UTF-8 + +*** START OF THIS PROJECT GUTENBERG EBOOK AMERICAN HANDBOOK OF THE DAGUERROTYPE *** + + + + +Produced by Gregory Walker, for the Digital Daguerreian Archive Project. + +[Illustration] + +This etext was created by Gregory Walker, Austin, Texas, for the +Digital Daguerreian Archive Project. + Page numbers explicitly referred to in the text are marked at their + beginning by “[page ##]” on a separate line. I hope this etext + inspires a wider interest in the origins of photography and in the + modern practice of the Daguerreian Art. + +[Updater’s note: In this version, the above page numbering convention +has been replaced by “{##}” sequences placed in line with the +surrounding text.] + +AMERICAN HAND BOOK OF THE DAGUERREOTYPE + +GIVING THE MOST APPROVED AND CONVENIENT METHODS FOR PREPARING THE +CHEMICALS, AND THE COMBINATIONS USED IN THE ART. + +CONTAINING THE DAGUERREOTYPE, ELECTROTYPE, AND VARIOUS OTHER PROCESSES +EMPLOYED IN TAKING HELIOGRAPHIC IMPRESSIONS. + +BY S. D. HUMPHREY + +FIFTH EDITION + +NEW YORK: PUBLISHED BY S. D. HUMPHREY 37 LISPENARD STREET + 1858 + +Entered, according to Act of Congress, in the year 1858, by S. D. +HUMPHREY, In the Clerk’s Office of the District Court of the Southern +District of New York. + +To J. GURNEY, WHOSE PROFESSIONAL SKILL, SCIENTIFIC ACCURACY, AND +ENERGETIC PERSEVERANCE, HAVE WON FOR HIM UNIVERSAL ESTEEM, THIS WORK IS +MOST RESPECTFULLY INSCRIBED. + + + + +PREFACE. + + +There is not an Amateur or practical Daguerreotypist, who has not felt +the want of a manual—Hand Book, giving concise and reliable information +for the processes, and preparations of the Agents employed in his +practice. + +Since portraits by the Daguerreotype are at this time believed to be +more durable than any other style of “Sun-drawing,” the author has hit +upon the present as being an appropriate time for the introduction of +the Fifth Edition of this work. The earlier edition having a long since +been wholly; exhausted, the one now before you is presented. + +The endeavor has been to point out the readiest and most approved +Methods of Operation, and condense in its pages; as much practical +information as its limits will admit. An extended Preface is +unnecessary, since the aim and scope of this work are sufficiently +indicated by the title. + +S. D. HUMPHREY NEW YORK, 1858. + + + + +CONTENTS + + +CHAPTER I. + +Polishing the Daguerreotype Plate—Buffing the Plate—Coating the +Plate—Exposure of the Plate in the Camera—Position Developing the +Daguerreotype—Exposure to Mercury—Removing the Coating—Gilding or +fixing the Image—Coloring Daguerreotype, . . . . . 18 + +CHAPTER II. + +Coloring Back Grounds—Transparent ditto—Gilding Dissolvent—Solution for +removing Specks—Solarized Impression—To Purify Water—Cleaning +Mercury—Adhesive Paper—Black Stain for Apparatus—Sealing Wax for +Bottles—Rouge—Rotten Stone—Potassa Solution—Hyposulphite +Solution—Substitute for do.—Gilding Solution—Solution for increasing +the Brilliancy of the Daguerreotype—Bleaching Solution;—Cold +Gilding—Neutralizing Agents—Buff Dryer—Keeping Buffs in order—Cleaning +Buckskins—Reflector for taking Views, . . . . 52 + +CHAPTER III. + +Bromine and its Compounds—Iodine and its Compounds—Chlorine and its +Compounds—Cyanide of Potassium—Hyposulphite of Soda—Hyphosulphite of +Gold—Nitric Acid—Nitro-Muriatic Acid—Hydrochloric Acid—Hydrofluoric +Acid—Sulphuric Acid—Accelerating Substances—Liquid Sensitives—Dry +Sensitives, etc., etc., . . . . . 72 + +CHAPTER IV. + +Light—Optics—Solar Spectrum—Decomposition of Light—Light, Heat, and +Actinism—Blue Paper and Color for the Walls of the Operating +Room—Proportions of Light, Heat and Actinism composing a +Sunbeam—Refraction—Reflection—Lenses—Copying Spherical +Aberration—Chromatic Aberration, . . . 131 + +CHAPTER V. + +To make Plates for the Daguerreotype—Determining the Time of Exposure +in the Camera—Instantaneous Process for Producing +Daguerreotype—Galvanizing the Daguerreotype Plate—Silvering +Solution—Daguerreotype without Mercury—Management of Chemicals—Hints +and Cautions—Electrotyping—Crayon Daguerreotypes—Illuminated +Daguerreotypes—Natural Colors in Heliography—Multiplying Daguerreotypes +on one Plate—Deposit in Gilding—Practical Hints on the Daguerreotype, . +. . 149 + +CHAPTER VI. + +An Account of Wolcott and Johnson’s Early experiments in the +Daguerreotype, . . . 188 + + + + +AMERICAN HAND-BOOK of THE DAGUERREOTYPE. + + + + +CHAPTER I. + + +Polishing the Daguerreotype Plate—Buffing the Plate—Coating the +Plate—Exposure of the Plate in the Camera—Position—Developing the +Daguerreotype—Exposure to Mercury—Removing the Coating—Gilding or +fixing the Image—Coloring Daguerreotype. + +Polishing the Daguerreotype Plate.—I shall endeavor to present to the +reader the process I have found productive of good and satisfactory +results, presenting the same in a clear and concise manner, so that any +one, by following the various manipulations given, will be enabled to +succeed. If there is any one part of the process in Daguerreotype in +which operators fail more than all others, it is in not properly +preparing the plate. It has truly been said that it would take a volume +to describe all the methods that have been suggested for polishing the +plate. + +I shall confine myself to the following description, which has been +successfully practised, also most generally adopted by our operators, +and I believe equal, if not superior to any other method, yet at the +same time it is not of so much importance what particular method is +employed, so that it be thoroughly and skillfully carried out. + +There is a general tendency with beginners to slight this operation; +hence the necessity of adopting a system which precludes the +possibility of doing so. During many years’ study and practice in the +art, I have tried numerous methods and substances for the better +accomplishment of the end in view, and have finally settled upon the +following, as being (so far as experience allows me to Judge) the modus +operandi, best suited to all circumstances; under no condition would I +approve of a method less rigorous or precise. + +The operator being provided with a bottle of finely prepared rotten +stone, cover the mouth of the bottle with a piece of thick paper, this +perforated with a pin so that the rotten stone can be dusted on the +plate. Fasten the plate on the holder, take the rotten stone (Becker’s +can always be depended upon), and dust on lightly until the surface is +freely covered; now drop on the plate’s surface a few drops of an +alcoholic solution.[1] + + [1] This solution is composed of equal parts of alcohol and water, for + the summer, and in winter three parts alcohol to one of water; a few + drops of potassa solution may be added, and is known to have a decided + effect upon the plate. + +Take a patch of Canton flannel; in order to prevent the moisture from +the hand it should have a thick, firm texture: with this rub the plate +in circles across, then back covering one-half of the former row of +circles in each crossing until you have gone over the plate and back to +the point of beginning, occupying at least half a minute in the +operation, for a small plate, and so in proportion for the other sizes. + +Care should be observed to keep the patch wet with the alcoholic +solution forming a paste on the surface of the plate; the motion of the +hand should be brisk and free, not hurried, and the pressure about +equal to that of a pound weight. When the cotton is disposed to adhere +to the plate, and slip from under the finger, spread the fore and +middle fingers a little apart, then pressing down, bring them together +in such a manner as to form a fold in the cloth between them, by which +means you will hold it perfectly secure. + +Avoid wetting the fingers, and should they perspire, wipe them often, +as the moisture penetrating the cotton and coming in contact with the +plate, would cause streaks it would be difficult to remove. I will here +remark that many operators use much more cotton flannel than there is +need of. I have found in my experience that a single patch, about one +and half inch square, will be better for cleaning a number of plates +than a new piece for every plate. This is the case for the wet, and for +the dryrubbing two or three pieces will be found to answer. Thus with +four or five cloths a dozen plates may be prepared. + +Some operators use prepared cotton, and think it more convenient than +the flannel. This may be had prepared free from seeds and in a very +perfect state, if wished. + +In going over the plate, great care should be observed, in touching its +surface as equally as possible. The greatest care should be taken +neither to touch the plate with the fingers, nor that part of the +cotton flannel which is to come in contact with its surface; take a +clean piece of flannel by one corner, snap it smartly to free it from +dust and loose fibres, lay it face-side upward, dust on a little fine +rotten stone; with this, polish around, or across, or in circles, +lightly and briskly, passing gradually over the whole surface of the +plate, as was done before with the wet. The plate should now exhibit a +bright, clear, uniform surface, with a strong metallic lustre, +perfectly free from any appearance of film; if not, the last polished +should be continued until the effect is obtained, and when once +obtained, the plate is ready for buffing. + +Buffing the Plate.—There are a variety of ways and means employed in +this part of the operation. Some choose wheels, and others prefer the +ordinary hand-buff. I have been unable to detect any peculiar advantage +in the use of the wheel except in the facility of the operation; no +doubt, however, but there is a saving of time, particularly in the +preparation of the larger plates. For general use, we have not seen a +wheel better adapted for this purpose than the one patented by Messrs. +Lewis. + +It is generally well to use a hand-buff before placing the plate on the +wheel; this is in order to prevent, as far as possible, the dust or +other substance that may be on the surface of the plate from coming in +contact with the cover of the wheel. I will here follow out the use of +the hand-buffs (two are necessary) as they are mostly used. + +In the morning, before using the buffs, brush both as clean as +possible, in order to free them from dust; then with the blade of a +pair of shears, held perpendicular, rub the buffs from end to end; then +knock them both together in order to free them from all dust or other +substances, occasionally exposing them to the sun or to the fire. + +With one of the buffs (reserving the finest and softest for the last +operation), powder its face with fine rouge and brush off slightly, +leaving only the finest particles in it. Every operator should have two +plate-holders; one for cleaning and one for buffing the plate; for when +using only one, the rotten stone is liable to get on the buff and +scratch the plate. + +Rest the fingers of the left hand on the back of the buff, near the +farther end, with about the same pressure as in cleaning, while with +the right you bear on the handle to correspond, and give the buff a +free, easy, horizontal motion, passing it very nearly the whole length +over the plate each time. Continue this operation in such a manner that +the plate will on all parts of its surface have received an equal +amount of polish. This buff once well filled with polish, add but +little after, say a small quantity once in two or three plates. The +polish as well as the buffs must be kept perfectly dry. + +The second buff should always be in the best order, and if this is the +case, but little polish after the first need be used. Much depends upon +the last finish of the surface of the plate, and as a fine impression +is desired in the same ratio, the operator must exercise care and skill +in this operation. Some buff the smaller plates on the hands, by +resting them on the fingers in such a manner that the buff cannot touch +them; some by holding the edges with thumb and little finger, with the +remaining fingers under, or on the back; and others buff on the holder. +When this last method is adopted, it requires the greatest caution to +prevent the dust from getting on the buff. The holder should be wiped +clean. + +The plate frequently slips off or around, and the buff comes in contact +with the bed of the holder. When, however, the operator is so +unfortunate as to meet with this mishap, the utmost care must be +observed in thoroughly cleaning the buff cover before further buffing. +In this last buffing it may be continued as before, except without the +application of polish powder to the last buff. Examine the surface +occasionally, and buff more lightly towards the close of the operation, +using at last the mere weight of the buff. This last buffing should +occupy as long a time as the first. + +The point to be aimed at is, the production of a surface of such +exquisite polish as to be itself invisible, like the surface of a +mirror. The secret of producing pictures discernible in any light, lies +in this: the more dark, deep and mirror-like the surface of the plate, +the more nearly do we approach to perfection. + +In all cases, very light and long continued buffing is productive of +the greater success, since by that means a more perfect polish can be +obtained. + +The question is often asked, why is it that the plates receive the +coating so unevenly? I will answer by saying that it may arise from two +causes: the first and most general cause is that those parts of the +plate’s surface which will receive the heaviest coating have been more +thoroughly polished, and the consequence is that it is more sensitive +to the chemical operation; second, and might perhaps be considered a +part of the first, the heat of the plate may not be equal in all its +parts; this may arise from the heat caused by the friction in buffing. +It is a well known fact, with which every observing practitioner is +familiar, that a silver plate at a temperature of 45 deg. or less, +exposed to the vapors of iodine, is less sensitive and takes a longer +time to coat, than when it is at a temperature of 60 deg. or more. + +Whenever a view is to be taken, or any impression which requires the +plate to be turned on the side, it should be buffed in the other +direction, so that the marks will always be horizontal, when the +picture is in position. With the finest possible polish, the plate is +ready for the coating box. + +The question is often asked by operators, what is the state of the +plate when polished and allowed to stand for a time before using? To +meet this point we hare only to consider the silver and the power +acting upon it. Pure atmosphere does not act upon silver; but we do not +have this about in our operating rooms, as it is more or less charged +with sulphurated hydrogen, which soon tarnishes the surface of the +plate with a film of brown sulphurate. It is this that sometimes causes +the specks which appear on finishing the impression, and are a great +annoyance. Hence we see that the plate should be buffed just before +receiving the vapor of iodine. Mr Hunt gives his opinion of the use of +diluted nitric acid as the best solution for freeing, the surface of +the plate; he says: + +“Numerous experiments on plated copper, pure silver plates, and on +silvered glass and paper, have convinced me that the first operation of +polishing with nitric acid, etc., is essential to the production of the +most sensitive surface. All who will take the trouble to examine the +subject, will soon be convinced that the acid softens the silver, +bringing it to a state in which it is extremely susceptible of being +either oxydized or iodized, according as the circumstances may occur of +its exposure to the atmosphere or the iodine.” + +I cannot see the objection to this solution; not, however, in general +use. Our operators do not find it of sufficient importance to the +success of their pictures to accept it, the alcoholic solution being in +its nature less objectionable. + +I will say here, that a plate submitted to only an ordinary polish is +found to contain numberless minute particles of the powder made use of. +Should the same plate be buffed for a long time, the polish will nearly +all disappear, leaving the cavities in the surface free for the action +of agents employed in subsequent operation. For this reason, I find +that great amount of polishing powder should not be applied to the last +buff, and it is obvious that three buffs can be employed to adventure; +the two last should not receive any polishing materials. I have +examined a plate that was considered to possess a fine finish, and +similar had produced good impressions; these same plates, when +subjected to a long and light buffing, would present a surface no finer +in appearance to the naked eye; but upon exposure to the solar +radiation, would produce a well-defined image in one fourth less time +than the plate without the extra buffing. + +Coating the Plate.—For this purpose our mechanics and artists have +provided a simple apparatus called a coating-box, which is so arranged +as to be perfectly tight, retaining the vapor of the iodine or +accelerators, and at the same time allowing, by means of a slide, the +exposure of the plate to these vapors. They can readily be obtained by +application to any dealer, all of whom can furnish them. + +The principal difficulty in coating the plate, is that of preserving +the exact proportion between the quantity of iodine and bromine, or +quick. It is here necessary to say, that hardly any two persons see +alike the same degree of color, so as to be enabled to judge correctly +the exact tint, i. e. what one might describe as light rose red, might +appear to another as bright or cherry red; consequently, the only rule +for the student in Daguerreotype, is to study what appears to him to be +the particular tint or shade required to aid him to produce the desired +result. Practise has proved that but a slight variation in the chemical +coating, of the Daguerreotype plate will very materially affect the +final result. + +The operator will proportion the coating of iodine and bromine or +accelerators according to the strength and composition of the latter. + +Experience proves that the common impressions, iodized to a rather +light yellow gold tint, and brought by the bromine to a very light, +rose color, have their whites very intense, and their deep shades very +black. It is also known that if you employ a thicker coating of iodine +and apply upon it a proportionate tint of bromine, so as to obtain a +deep rose tint, delineations will be less marked, and the image have a +softer tone. This effect has been obvious to everyone who has practised +the art. Thus I may observe that the light coatings produce strong +contrast of light and shade, and that this contrast grows gradually +less, until in the very heavy coating it almost wholly disappears. From +this it will readily be perceived that the middle shades are the ones +to be desired for representing the harmonious blending of the lights +and shades. + +Then, if we examine, with respect to strength, or depth of tone, and +sharpness of impression, we see that the light coating, produces a very +sharp but shallow impression; while the other extreme gives a deep but +very dull one. Here, then, are still better reasons for avoiding either +extreme. The changes through which the plate passes in coating may be +considered a yellow straw color or dark orange yellow, a rose color +more or less dark in tint, or red violet, steel blue or indigo, and +lastly green. After attaining this latter color, the plate resumes a +light yellow tint, and continues to pass successively a second time, +with very few exceptions, through all the shades above mentioned. + +I will here present some excellent remarks upon this subject by Mr. +Finley. This gentleman says: + +“It is well known to all who have given much attention to the subject, +that an excess of iodine gives the light portions of objects with +peculiar strength and clearness, while the darker parts are retarded, +as it were, and not brought out by that length of exposure which +suffices for the former. Hence, statuary, monuments, and all objects of +like character, were remarkably well delineated by the original process +of Daguerre; the plate being coated with iodine alone. An excess of +bromine, to a certain degree, has the opposite effect; the white +portions of the impression appearing of a dull, leaden hue, while those +which should be black, or dark, appear quite light. This being the +case, I conclude there must be a point between the two extremes where +light and dark objects will be in photogenic equilibrium. The great +object, therefore, is to maintain, as nearly as possible, a perfect +balance between the two elements entering into union to form the +sensitive coating of the plate, in order that the lights and shades be +truly and faithfully represented, and that all objects, whether light +or dark, be made to appear so far conformable to nature, as is +consistent with the difference in the photogenic energy of the +different colored rays of light. It is this nicely-balanced combination +which ensures, in the highest degree, a union of the essential +qualities of a fine Daguerreotype, viz., clearness and strength, with +softness and purity of tone. + +“So far as I know, it is the universal practice of operators to judge +of the proportion of iodine and bromine in coating the plate, by two +standards of color the one fixed upon for the iodine, the other for the +additional coating of bromine. Now I maintain that these alone form a +very fallacious standard; first, because the color appears to the eye +either lighter or darker, according as there is more or less light by +which we inspect the coating; and secondly, because if it occur that we +are deceived in obtaining the exact tint for the first coating, we are +worse misled in obtaining the second, for if the iodine coating be too +light, then an undue proportion of bromine is used in order to bring it +to the second standard, and vice versa.” + +The iodine box should be kept clean and dry. The plate immediately +after the last buffing, should be placed over the iodine, and the +coating will depend upon the character of the tone of the impression +desired. Coating over dry iodine to an orange color, then over the +accelerator, to a light rose, and back over iodine one sixth as long as +first coating, will produce a fine, soft tone, and is the coating +generally used for most accelerators. The plate iodized to a dark +orange yellow, or tinged slightly with incipient rose color, coated +over the accelerator to a deep rose red, then back over iodine +one-tenth as long as at first coating, gives a clear, strong, bold, +deep impression. + +I will here state a singular fact, which is not generally known to the +operator. If a plate, coated over the iodine to a rose red, and then +exposed to strong dry quick or weak bromine water, so that a change of +color can be seen, then recoated over the iodine twice as long as at +first coating, it will be found far more sensitive when exposed to the +light than when it has been recoated over the iodine one-fourth of the +time of the first coating. + +Probably the best accelerating combination is the American compound +formerly known as “Gurney’s American compound,” or some of the +combinations of bromide of lime. The first is thought to possess +perhaps more uniformity in its action than any other combination I have +ever used. + +The plate once coated should be kept excluded from the light by means +of the plate holder for the camera box. + +I will notice one of the principal causes having a tendency to prevent +the perfect uniformity of chemical action, between the iodine and +silver; hydrogen, or the moisture in the atmosphere, makes a very +perceptible barrier. This moisture may arise as the result of the cold, +from a want of friction in the buffing of the plate, which, coming in +contact with the warmer air, as a writer on this subject says: + +“It is well known that as often as bodies, when cold, are exposed to a +warmer air, the humidity contained in them is condensed. It is to this +effect that we must attribute the difficulty experienced in operating +in most cases.” This is corroborated by the results experienced by our +operators. So it is seen that the plate should be of a temperature +above that of the atmosphere. Mr. Gurney submits his plates to a gentle +heat from a spirit lamp just before exposing them to the vapor of +iodine. Experience has convinced me that a plate heated to about 80 +deg. before being exposed to iodine will present a far better defined +image than a plate at a temperature of 50 deg. I account for this by +noticing that, at a higher temperature, the plate throws off any larger +crystals that might otherwise be deposited, receiving only the finer, +thus producing a more perfect chemical combination of iodide of silver. +I would call the attention of the operator to this point, as presenting +something of interest, and which may direct in a way of accelerating +the future operations. + +That the presence of a film of moisture over the plate is a preventive +of uniform chemical action, may be readily understood from the fact +that iodine is almost insoluble in water, requiring seven thousand +parts of water to dissolve one of iodine, or one grain to a gallon of +water. Yet its affinities for silver and other substances are so +powerful as to prevent its existing in an insulated state, hence we can +account for the frequent occurrence of a plate presenting parts of an +image over its surface. It is quite evident that those parts of plate’s +surface covered with moisture are nothing like as sensitive to the +iodine as those parts perfectly free. + +Exposure of the plate in the Camera, and Position.—The time of exposure +necessary to produce an image upon the Daguerreotype plate, can only be +determined by experiment, and requires a liberality of judgment to be +exercised on the part of the operator. The constant variation of the +light renders it impossible to lay down any exact rule upon this point. +Light is not alone to be considered; the amount of coating exercises a +deviating influence, also the subjects to be represented are not +equally photogenic, some requiring much longer time of exposure than +others. This may be easily observed by exposing the plate at the same +time to a plaster bust and a piece of black velvet, the first being a +much stronger reflector of light than the latter: the time necessary to +produce a well developed image of the velvet being about six times +longer than that required to produce an equally defined image of +plaster. The manner of judging correctly of the time is by the +appearance of impression after it has been developed by the mercurial +vapors. Should it present a deep blue or black appearance it is +solarized or over-timed. This sometimes is to an extent, that a perfect +negative is formed, the white being represented black, and the dark +light. + +An object requiring the particular care and attention of the operator +is the proper focus. It is not unfrequently the complaint of sitters +that their hands are represented as being magnified and greatly out of +proportion with the general figure. This is the case also with the nose +and eyes, but in a less degree. As this cannot be wholly remedied, it +is desirous to come as near as possible, and in order to do this, it is +necessary to present the figure in such a position as to bring it as +nearly as possible upon the same plane by making all parts nearly at +equal distance from the lenses. This must be done by the sitter +inclining the head and bust formed to a natural, easy position, and +placing the hands closely to the body, thus preserving a propel +proportion, and giving a lively familiarity to the general impression. +It is not an uncommon fault among our less experienced operators to +give a front view of the face of nearly every individual, regardless of +any particular form, and this is often insisted upon by the sitter,[2] +who seems to think the truth of the picture exists principally in the +eyes staring the beholder full in the face. + + [2] I might here picture some curious scenes experienced by our + operators Every one is familiar with a certain class of our community + whose ideas of the importance of a free and easy position of the body + are too closely confined with stays, attention to toilet, tightly + fitting dress coats and the like, to admit of being represented as if + nature had endowed them with least possible power of flexibility. To + such we would suggest the following, to be well learned and retained + in the mind while presenting themselves before the Daguerreotype + camera: + +“The experience of one who has often been Daguerreotyped, is, to let +the operator have his own way.” + +Nothing, in many instances, can be more out of place in a Daguerreotype +portrait than this, for let a man with a thin, long, +defeated-politician-face, be represented by a directly front view, we +have, to all appearances, increased the width of the face to such an +extent as to reveal it flat and broad, losing the characteristic point +by which it would be the most readily recognized. The method we should +adopt in taking the likeness of such an individual as above, would be +to turn the face from the camera, so as to present the end of the nose +and the prominence of the cheek bone equally distant from the lenses, +and then focusing on the corner of the eye towards the nose, we cannot +in many cases, fail to produce an image with the lips, chin, hair, eyes +and forehead in the minutest possible definition. + +It should be the study of every operator to notice the effect of the +lights and shades while arranging the sitter, and at the same time be +very particular to give ease in the position. + +No matter how successful the chemical effect may have been, should the +image appear stiff and monument-like, all is lost. “In the masterpiece, +grace and elegance must be combined.” + +I will here use the words of another, which are very true: + +“So great is the difference in many faces, when inspected in opposite +directions, that one of the two views, however accurately taken, would +not communicate the likeness—it not being, the usually observed +characteristic form. When the right view of the head is obtained, it is +first necessary to consider the size of the plate it is to be taken on, +so as to form an idea of the proportion the head should bear to it. The +mind must arrange these points before we commence, or we shall find +everything, too large or too small for the happy proportion of the +picture, and the conveying of a just notion of the stature. The work +will have to be done over, and time sacrificed, if this is not attended +to. The adjustment of the head to the size of the plate (as seen from +the margin of the mat), is not to be taught: everyone must bring +himself, by scrutinizing practice, to mathematical accuracy; for +something will be discovered in every face which can be surmounted only +by experience. + +“The eye nearest the camera, in a three-quarter-face, is placed in the +middle of the breadth of the plate; the chin, in a person of middle +stature, in the middle of the length, and higher according to the +proportional height of the person.” + +In regard to the proper elevation of the camera, it may be here stated +that I have found it best in taking portraits where the hands are +introduced, to place the camera at about equal height with the eyes of +the sitter, in order to bring the face and hands equi-distant from the +tube. It will be found, if the above be followed, that by attaching a +string to the camera tube, and making a semi-circle, that the face and +hands of the sitter will occupy a corresponding distance, and the +consequence is that the impression will appear without the hands being +magnified. It has been found that a person with a freckly face can have +as fine, fair, and clear an impression as the most perfect complexion; +this may be done by the subject rubbing the face until it is very red. +The effect is to lessen the contrast, by giving the freckles and skin +the same color and the photogenic intensity of the red and yellow being +nearly the same, an impression can be produced perfectly clear. + +When a child is to be taken, and there are doubts of its keeping still, +the operation may be accelerated by placing it nearer the window +bringing the screen nearer, and placing a white muslin cloth over the +head; this will enable you to work in one third of the usual time. +Should the person move, or the plate become exposed to the light, it +may be restored to its original sensitiveness by placing it over the +quick, one or two seconds. + +Developing the Daguerreotype.—After the plate has been submitted to the +operation of the light, the image is still invisible. It requires to be +exposed to the vapors of heated mercury. It is not absolutely necessary +to apply artificial heat to the mercury to develop the image, for fair +proofs have been produced by placing a plate over the bath at the +ordinary temperature of the atmosphere. This plan, however, requires a +long time and cannot be adopted in practice, even if it were advisable. +The time more usually required in developing the image over the +mercurial vapors, is about two minutes, and the temperature is raised +to a point necessary to produce the desired effect in that time. This +point varies as indicated by different scales, but for the ordinary +scales it is not far from 90 deg. cen. + +The mercury bath is accompanied with a centigrade thermometer, by which +the heat is regulated. Those furnished by the manufacturers are not +always correct, and it requires some experience to find the proper +degree on the scale. + +I would here remark that it is advisable, when placing the spirit lamp +under the bath, to so arrange it that the position of applied heat +should always be on the same point, viz., should the heat be directly +under the bulb containing the thermometer it would raise the mercury in +the tube to the point marked, and the temperature of that in the bath +would be far below what it should be; hence it is (where time is +followed for developing) that many failures occur. This is observed +more readily in the large baths made of thick iron, particularly upon +first heating. In practice I apply the heat as nearly as possible +between the centre of the bottom of the bath and the bulb containing +the mercury tube. It is advisable to keep the lamp lighted under the +bath from the time of commencing in the morning to the close of +business at night. By this means you have a uniformity of action, that +cannot be otherwise obtained. + +It is well known to the experienced Daguerreotypist, that different +atmospheres have a decided effect upon the mercury in developing the +Daguerreotype. It will require a greater degree of heat for one +atmosphere than for another. Experience alone determines this little +difference. + +In summer, on cloudy and stormy days, mercurial vapors rise more +readily and quickly than in the temperature of autumn or winter. From +60 degrees upwards towards the boiling point (660 deg.), the vapors of +mercury rise in greater abundance and collect in larger globules on +cold surfaces. + +For various reasons I prefer a high temperature and short exposure. It +accelerates the process. It renders the lights of the picture more +strong and clear, while the deep shades are more intense. It gives a +finer lustre to the drapery. The solarized portions also are very +seldom blue, especially after gilding. If heated too high, however, the +light parts become of a dead, chalky white, and the shadows are injured +by numerous little globules of mercury deposited over them. Just the +right quantity of mercury leaves the impression of a transparent, +pearly white tone, which improves in the highest degree in gilding. To +mercurialize with exactness is a nice point. If there is reason to +suspect having timed rather short in the camera, reduce the time over +mercury in a corresponding proportion. A dark impression will be ruined +by the quantity of mercury which would only improve a light one. + +If practicable, it is most expedient that the plate be submitted to the +action of mercury immediately on coming from the camera. I have +frequently, however, carried plates for miles in the plate-holders and +after exposing in the camera, brought them back to expose to mercury, +and obtained fair proofs; but for the reason before given, it is +advisable to carry along the bath, and bring out the impression on the +spot. + +It is sometimes the practice of inexperienced operators to take the +plate off the bath and examine the impression by solar light. This plan +should be abandoned, as it is almost sure to produce a dense blue film +over the shadows. + +This I am led to believe is occasioned by the action of light on the +yet sensitive portions of the plate, and made to appear only by +subsequent exposure to mercury, being equivalent to solarization. + +There has been little said by our professors upon the subject of the +position of the plates while exposed to the mercurial vapour. Mr. Hunt, +in referring to this subject, says: “Daguerre himself laid much stress +upon the necessity of exposing the plate to the mercury at an angle of +about 45 deg.. This, perhaps, is the most convenient position as it +enables the operator to view the plate distinctly, and watch the +development of the design; but beyond this, I am satisfied there exists +no real necessity for angular position. Both horizontally and +vertically, I have often produced equally effective Daguerreotypes.” I +presume from the last sentence of Mr. Hunt, that he has confined his +experiments to the smaller sized plates. Hence he may not have thought +of the effect of the vertical exposure of a large plate. + +In America this is a subject of no little importance. When an +impression is to be developed upon a plate fifteen by seventeen inches, +were we to use an angle of about 45 deg., it would be found to make a +perceptible difference in the appearance of the image. By examining the +wood tops of our baths as formerly made, it will be found that there is +a great variation in the distance from the mercury to the different +portions of the plate. By measuring one of these tops for the size +plate above mentioned, I find the distance to the nearest point between +the mercury and the plate, to be thirteen, and the middle point +sixteen, and the furthest point twenty-one and a half inches: by this +we see that one point of the plate is eight and a half inches further +from the mercury than the nearest point; even this is not the variation +there would necessarily be, were we to adopt the angle of 45 deg. as +urged by Daguerre. + +Among our principal professors, the bevel top will not be found in use +where the large plates are used. Should any one feel desirous to test +more minutely the effect produced by a bevel top bath, I would suggest +to them to place a frame, so constructed as to hold three sixth size +plates, and fit it to the top of the bath, and so arrange it with +openings that the plates may be placed, one at the nearest point of the +mercury, the second midway, and the third to the greatest distance, and +by placing the plates over at one and the same time, the experimenter +will be enabled to judge if there exists a difference in the +developing. In speaking of the above, reference is had to baths to the +ordinary heights used by operators. + +We will now proceed to examine the effect produced by mercurial vapor +upon the plate at different lengths of exposure. In some investigations +which I have made upon the appearance of the Daguerreotype impressions +when developed over mercury at 90 deg. C. (194 deg. F.), the following +was the result. Plates, coated and exposed to light in our usual manner +of operating, produced on exposure of + +1/2 minute, whole impression, deep blue. + +1 minute, ashy and flat; no shadows; linen, deep blue. + +1 1/2 minute, coarse and spongy; shadows, muddy; drapery, dirty reddish +brown. + +2 minutes, shallow or watery; shadows, yellowish; drapery, brown. + +2 1/4 minutes, soft; face, scarcely white; shadows, neutral; drapery, +fine dark brown linen somewhat blue. + +2 1/2 minutes, clear and pearly; shadows, clear and positive, of a +purple tint; drapery, jet black, with the dark shades slightly frosted +with mercury. + +2 3/4 to 3 minutes, hard and chalky; shadows, harsh; drapery, +roughened, and misty with excess of mercury. + +The foregoing results will be found general. + +There are numerous opinions among our operators in regard to the +quantity of mercury necessary for a bath. As regards this, I need only +say, similar results occur when two pounds or two ounces are used, but +the quantity generally employed is about a quarter of a pound. I am of +the opinion that one ounce will answer as well as a larger quantity. I +know of no better proof in favor of a small quantity than that +presented in the following incident. Several years since, an operator +(Mr. Senter, of Auburn, N.Y.) of my acquaintance, was requested to go +several miles to take a Daguerreotype portrait of a deceased person. He +packed up his apparatus and proceeded over a rough road for some +distance to the house where he was to take the portrait, and arranging +his apparatus, with all the expedition which the occasion required, +after having everything in usual order (as was supposed), he proceeded +and took some ten or twelve very superior impressions. They were fine, +clear, and well developed. After taking the number ordered, he +proceeded to repack his apparatus, and to his surprise, when he took up +the bottle he carried the mercury in, he found it still filled, and +none in the bath, except only such particles as had adhered to the +sides, after dusting and being jolted for several miles over the rough +road. From this it will be seen that a very little mercury will suffice +to develop fine proofs. I saw some of the impressions referred to +above, and they were certainly well developed, and very superior +specimens of our art. + +Removing the Coating.—After the impression has been developed over the +mercurial vapor, the next step is to remove the sensitive coating. For +this purpose the following solution is used: + +Put about two ounces of hyposulphite of soda in a pint of water, which +should always be filtered before using. A convenient way of doing this +is to have two bottles, and a large funnel with a sponge pressed into +the neck of it; or, what is better, some filtering paper folded in it. +The solution in one bottle, the funnel is placed in the other, and the +picture held over it; when the solution is poured on the plate, it runs +from it into the filter, and is always ready for use. + +It is best that the washing be done immediately on the plate coming +from the mercury bath. If allowed to stand long with the coating on, it +assumes a very dark tint—as the operation of the light continues, +though less active than while exposed in the camera, and destroys that +brightness which would otherwise have been obtained. It is preferable +to wash and gild a picture without it first being dried; yet when there +are doubts of its giving satisfaction, there would sometimes be a +saving by drying and getting the decision of the subject before +gilding, as this last injures the plate for another impression. First, +light your spirit-lamp, then with your plyers take the plate by the +lower right-hand corner, holding it in such a manner that the plyers +will form in a line with the upper left-hand corner; pour on, slowly, +the hyposulphite solution, slightly agitating the plate, until all the +coating is dissolved off; then rinse off with clean water, and if it is +not to be gilded, dry by holding the plate perpendicular with the +bottom left-hand corner lowest, and applying the blaze of the +spirit-lamp to the back, at the same time blowing gently downward on +the face of the plate. + +The hyposulphite solution should be often filtered through a sponge, +and it will answer for a great number of washings. Yet it is observed +that the mercury collects in this solution in small globules; these +often come in contact with the plate, causing white spots, which spoil +the impression. They should be guarded against, and the solution +renewed. Again, in order to prevent streaks or scum on the surface of +the plate, it is necessary that the coating should be removed with a +good degree of uniformity. I find in practice that the hyposulphite of +soda in our market varies much as regards strength, and consequently +the rule to be adopted is to make a solution of sufficient strength to +remove the coating in about ten seconds. I am aware that it may be said +that this strong solution would have a tendency to injure the +impression by destroying in a measure the sharpness of outline. To meet +this, it need only to be said that the preventive is, to not let the +solution rest on the surface of the plate for a longer time than is +absolutely necessary, and then it should be drenched copiously with +water; hence a chemical action upon the image is prevented and the +general operation facilitated. This plan is adopted by our first +operators with the greatest success. + +If the operator should allow the hyposulphite solution to run over the +plate unevenly, it is quite likely that white or blue streaks would +result. These it is impossible to remove without injury to the +impression. Some, in order to prevent this, breathe over the surface, +thus moistening it and putting it in a condition to receive the +solution with greater uniformity. The plate should be well washed with +water before gilding. + +Gilding, or Fixing the Image.—The next process to be given is that for +fixing the image on the plate. This is done by precipitating a thin +film of gold over the surface and is productive of the most brilliant +effect when prepared immediately after the plate has been washed with +water after the application of the hyposulphite solution, and before +the plate has been allowed to dry. When, however, the plate has been +dried and allowed to stand for any time, before gilding, the +hyposulphite wash should be applied as at first, in order to destroy +any chemical coating that may have been formed on exposure of the plate +to the air. For gilding the larger plates, we have a gilding stand so +constructed that the plate can be put on a perfect level. In practice, +I prefer holding the plate with nippers, fastened at one corner. Hold +the plate in the same manner as in removing the coating; pour on the +gilding, newly filtered, until the surface is wholly covered, and with +the blaze of the spirit lamp, at least three inches high, apply it to +the back of the plate, moving it about, that the surface may be heated +with as much uniformity as possible. Continuing this operation, the +surface will generally become covered with small yellow bubbles which +soon disappear, leaving the image clear and distinct. + +It is advisable to make use of a lamp having a sufficiently strong +flame to produce the effect in a few minutes. If after a first heating, +it is found that the impression can admit of a greater degree of +intensity, it might be heated anew; but that is seldom necessary, and +often by trying to do too, well, the operator, if he persists in +heating certain parts of the plate, may find the liquid dry up just +above the flame, and inevitably cause a stain; [3] or else the blacks +are covered with a film, or even the coating of gold may suddenly +exfoliate, when small particles are detached from the plate. The +impression is then entirely spoiled, but the plate may be re-polished. + + [3] This can be remedied, however, if it is immediately washed over + with the same solution that is on the plate, so that the surface shall + not become cool; continue for a short time to apply the lamp under, + and agitate the plate slightly, and it will soon be free from all + imperfections and give a fine clear tone. + +It is not unfrequent that the surface assumes a dark, cloudy +appearance. This is generally the best sign that the gilding will bring +out the impression with the greatest degree of distinctness. Soon, the +clouds gradually begin to disappear, and, “like a thing of life” stands +forth the image, clothed with all the brilliancy and clearness that the +combined efforts of nature and art can produce. When in the operator’s +judgment the operation has arrived at the highest state of perfection, +rinse suddenly, with an abundance of clean water, and dry as before +described. + +When an impression is dark, the gilding process may be longer +continued; but when light, it should be gilded quickly, as lengthening +the time tends to bleach the impression and make it too white. The +cause of this appears to be, that with a moderate heat the chlorine is +merely set free from the gold, and remaining in the solution, instead +of being driven off, with its powerful bleaching, properties, it +immediately acts upon the shades of the picture. A dark impression can +thus, by a low heat, long-continued, be made quite light. To procure +the best effect, then, heat suddenly with a large blaze, and judging it +to be at the maximum, cool as suddenly as possible. + +When the hyposulphite of gold is used instead of the chloride, a less +heat should be employed. + +Coloring Daguerreotypes.—Of all the so-called improvements in the +Daguerreotype, the coloring is the least worthy of notice. Yet the +operator is often, in fact most generally, called upon to hide an +excellent specimen under paint. I can conceive of nothing more perfect +in a Daguerreotype than a finely-developed image, with clearness of +lights and shadows, possessing the lively tone resulting from good +gilding. Such pictures, however, are not always had, and then color may +perform the part of hiding the imperfections. We present the following +method as given in Willat’s Manual: + +“Daguerreotype portraits are now commonly met with beautifully colored; +but the coloring is a process requiring great care and judgment, and +many good pictures are spoiled in fruitless experiments. Several +different methods of coloring have been proposed. The simplest mode +appears to be that of using dry colors prepared in the following +manner: A little of the color required, very finely ground, is thrown +into a glass containing water, in which a few grains of gum arabic have +been dissolved. After standing a few moments, the mixture may be passed +through bibulous paper, and the residue perfectly dried for use. The +principal colors used are Carmine, Chrome Yellow, Burnt Sienna, +Ultramarine and White; boxes fitted with sets of colors properly +prepared, may be obtained of the dealers, and include Carmine, White, +Lilac, Sky Blue, Pink, Yellow, Flesh color, Orange, Brown, Purple, +Light Green, Dark Green and Blue. With a few colors, however, all the +rest may be made thus: Orange, by Yellow and Red; Purple, with Blue and +Red; Green, Blue and Yellow; Brown, with Umber, Carmine and Lamp Black; +Scarlet, Carmine and Light Red. While it is true that a little color +may relieve the dark metallic look of some Daguerreotypes, it must not +be concealed that the covering of the fine delicate outline and +exquisite gradations of tone of a good picture with such a coating, is +barbarous and unartistic. + +“The prevaling taste is, however, decidedly for colored proofs, and the +following directions will assist the amateur in ministering to this +perverted taste, should he be so inclined. The coloring should commence +with the face, and the flesh tint must be stippled on (not rubbed) with +a small camel’s-hair brush, beginning from the centre of the cheek, +taking great care not to go over the outline of the face, and also not +to have too much color in the brush; the eyes and eyebrows must not be +touched with color. After the flesh color is applied, take a piece of +very soft cotton and pass it very gently backwards and forwards over +the face, so as to soften down the color, and then apply the carmine to +give the required tint. For men, the darker tints should predominate, +and for women the warmer. Very light hair may be improved by a slight +tint of brown, or yellow and brown, according to the color. In coloring +the drapery, the same care must be used. No rules can be laid down for +all the different colors required, and the amateur had better obtain +the assistance or advice of some one accustomed to the use of colors. A +little white with a dash of blue or a little silver, will improve white +linen, lace, etc. The jewelry may be touched with gold or silver from +the shells, moistened with distilled water, and laid on with a +fine-pointed sable-hair brush. + +“Brilliants may be represented by picking the plate with the point of a +pin or knife.” + + + + +CHAPTER II. + +MISCELLANEOUS. + + +Coloring Back Grounds—Transparent ditto—Gilding Dissolvent Solution for +removing Specks—Solarized Impression—To Purify Water—Cleaning +Mercury—Adhesive Paper—Black Stain for Apparatus—Sealing Wax for +Bottles—Rouge—Rotten Stone—Potassa Solution—Hyposulphite +Solution—Substitute for do.—Gilding Solution—Solution for increasing +the Brilliancy of the Daguerreotype—Bleaching Solution;—Cold +Gilding—Neutralizing Agents—Buff Dryer—Keeping Buffs in order—Cleaning +Buckskins—Reflector for taking Views. + +To Color Back-grounds—To obtain a properly colored back ground is a +matter of no little importance to the Daguerreotype operator. I had +nearly exhausted all patience, and tried the skill of painters to +obtain a back-ground that would be suitable to my purpose; but all to +no avail. At last I adopted the following method, and at a cost of +coloring of twenty-five cents, can now produce a back-ground far more +valuable than those which had cost five dollars before. + +Take common earth paint, such as is used in painting roofs; mix this +with water to about the consistency of cream; then to four quarts of +this mixture add about one pint of glue water (common glue dissolved in +water, also about as thick as cream). This last will cause the paint to +adhere to the cloth, to which it is applied with a common white-wash +brush. By applying the brush on the coating while it is wet, it may be +so blended that not a line can be seen, and a perfectly smooth color of +any shade can be obtained. The shade of color I use is a light +reddish-brown. Tripoli, rotten-stone, or any earthy matter, may be +applied in the same manner. + +Transparent or Invisible Back-ground.—I give this as originally +published in my System of Photography, 1849: + +“Take a large woollen blanket with long nap, the longer and rougher it +is the finer will be the effect produced; stretch it on a frame of +sufficient size, and suspend the frame at the centre of the upper end +by a string fastened to a nail in the ceiling, from three to five feet +back of the sitter. Having arranged this, fasten another string to the +side of the frame, and while the operation is going on in the camera, +swing the back-ground from right to left, continuing this during the +whole time of sitting, and you have a clear “transparent” back-ground, +which throws the image out in bold relief, and renders the surface of +the plate invisible. If equalled at all it is only by atmospheric +back-ground. I consider it to be the best ever known, and think it +needs but to be tried to afford satisfactory proof that it is so. +Although used by few before, since the first edition of this work at +least two thirds of the operators have adopted its use; for any one can +at once understand the principle and the effect which it produces.” + +It may be added that a motion imparted to to any back-ground where +softness is desired, produces an excellent effect. + +Gilding Dissolvent.—To one quart of muriatic acid add as much oxide of +iron (common iron rust) as it will dissolve in two days. This may be +done by putting in the oxide in excess. It should be frequently shook, +and when wanted for bottling it should be allowed to stand in order to +settle. When this is done the solution may be poured off, and reduced +by adding to it an equal quantity of water; then it is ready for use. +This constitutes a gilding dissolvent now in our market. + +Solution for Removing Specks.—There is probably no one cause of +complaint so general as “what makes those black specks?” There are +several causes which produce them, and probably the most general are +dust, rouge, or a spray of moisture on the plate. It this be the case, +there is no solution which can remove them, as they have prevented a +chemical action with the silver, and their removal would only expose +the surface of the plate which in itself would afford a contrast with +the impression. Another and less dangerous source of these specks is +organic matter contained in the solution employed in dissolving the +chemicals, or the water in washing. Much of the hyposulphite of soda in +market contains a sulphuret, which, coming in contact with the silver +surface, immediately causes oxidation. Such spots, as well also as most +all others found on the plate after it has been exposed in the camera, +can be removed by the following, solution: To one ounce of water add a +piece of cyanide of potassium the size of a pea; filter the solution +and apply by pouring it on the surface of the plate. In all cases the +plate should first be wet with water. Apply a gentle heat, and soon the +spots disappear, leaving the impression clear and free from all organic +matter. + +In the absence of cyanide of potassium, a solution of pure hyposulphite +of soda will answer as a fair substitute. + +To Redeem, a Solarized Impression.—The Daguerreotype plate, prepared in +the ordinary manner, should be exposed in the camera a sufficient time +to solarize the impression. Then, before it be exposed to the vapor of +mercury, expose it for a very brief period to the vapor of either +chlorine, bromine or iodine. Then expose over mercury, as usual. I have +produced singularly interesting results by this process. + +To Purify Water.—Filter the water well, and then add about three drops +of nitric acid to the pint. This can be used as absolutely pure water, +but I would recommend the use of distilled water as preferable. + +Cleaning Mercury.—Make a small bag of chamois skin, pour in the +mercury, and squeeze it through the leather. Repeat this several times, +and filter by means of a funnel made of paper, with a very small +aperture, through which it will escape and leave the particles of dust, +or other substances, in the paper. A paper with a pinhole through it +will answer as well, and it is less difficult to make. + +Adhesive Paper.—Take gum arabic, four ounces, put it in a wide-mouthed +bottle and pour on water about one-third above the gum. Add half ounce +of isinglass, or fish glue, and a small piece of loaf sugar. Let all +dissolve, and spread over French letter paper, with a brush or piece of +sponge. If once spreading is not enough, perform the same operation a +second time. + +Black Stain for Apparatus.—Dissolve gum shellac in alcohol, or procure +shellac varnish at the druggists’, stir in lampblack, and apply with a +sponge or bit of rag. This will adhere to metal, as well as wood, and +is used for the inside of camera, tubes, etc. + +Sealing Wax for Bottles.—Melt together six parts rosin and one beeswax, +and add a small quantity of lampblack; or, if red is preferable, add +red lead. Common white wax is best, as most chemicals act less upon it. + +When bottles containing bromine are to be sealed, it is well to grease +the stopper. This, however, only when the bottle is in frequent use, +for if it were to be sent by any conveyance it would be likely to fly +out. + +Rouge.—The method employed by Lord Ross is probably unsurpassed in the +production of rouge. He has given his process as follows: + +“I prepare the peroxide of iron by precipitation with water of ammonia, +from a pure dilute solution of sulphate of iron; the precipitate is +washed, pressed in a screw press till nearly dry, and exposed to a heat +which in the dark appears a dull, low red. The only points of +importance are, that the sulphate of iron should be pure, that the +water of ammonia should be decidedly in excess, and that the heat +should not exceed that I have described. The color will be a bright +crimson inclining to yellow. I have tried both potash and soda, pure, +instead of water of ammonia, but after washing with some degree of +care, a trace of the alkali still remained, and the peroxide was of an +ochrey color, till overheated, and did not polish properly.” + +Care should be observed to apply rouge in a dry state to the surface of +the plate. + +I would remark, that so far as my experience has gone, I consider good +rouge fully equal to any other polishing, material for the last or +finishing polishing; consequently I shall not take up my space in +enumerating any of the great variety that find few advocates. + +Why Rouge is to be preferred.—“Because it burnishes better, and because +it assists in fixing the layer of gold, rendering it less susceptible +of being removed in scales when heated too much.” + +Rotten Stone.—“Purchase the best ground rotten stone of the druggist, +put a few ounces at a time in a wedgewood or porcelain mortar, with +plenty of clean rain water. This should have about forty drops of +nitric acid to the quart. Grind well, and after letting the mortar +stand two minutes, pour into a third. After remaining undisturbed eight +minutes, finally pour off into a fourth to settle. Rinse back the +sediment in the second and third, and grind over with a new batch. +Repeat the operation till you have all in the fourth vessel. Let this +stand several hours, and pour off the water very carefully. Set the +deposit in the sun, or by a stove to dry. When perfectly dry, +pulverize, and it is ready for use. With a little trouble you will +obtain in this way a much better article than can generally be bought +of dealers. For the last washing, alcohol, or a mixture of alcohol and +water, is preferable.” + +Potassa Solution.—The use of a solution of potassa in the preparation +of the plate was suggested in the early history of the Daguerreotype. +It was thought to possess some peculiar property for improving the tone +of the impression. It is used for moistening the rotten stone in +polishing the plate, and may be prepared by putting about an ounce and +a half of alcohol in a close bottle, and add half a stick of caustic +potash. This will soon become of a deep red color. For use, fill your +small bottle, having a quill in the cork, with alcohol, and add a few +drops of the above, or enough to change it to a bright orange or +saffron color. + +A Substitute for the Hyposulphite Solution.—M. DAGUERRE recommends the +use of a solution of salt water for removing the coating off the plate. +I found this of some service at one time during my travels. My +hyposulphite bottle got broke and its contents lost, so as only to +leave enough for preparing gilding. I resorted to the use of salt +solution, and found it to answer well. Make a saturated solution of +salt in water. First wash the plate with clear water; then immerse it +in the saline solution, when it should be agitated, and the coating +will soon disappear. Another process with a salt solution of half the +strength of the above is very interesting and effectual. The plate +having been dipped into cold water, is placed in a solution of common +salt, of moderate strength; it lies without being acted upon at all; +but if it be now touched on one corner with a piece of zinc, which has +been scraped bright, the yellow coat of iodine moves off like a wave +and disappears. It is a very pretty process. The zinc and silver +forming together a voltaic pair, with the salt water intervening, +oxidation of the zinc takes place, and the silver surface commences to +evolve hydrogen gas; while this is in a nascent condition it decomposes +the film of iodide of silver, giving rise to the production of +hydriodic acid, which is very soluble in water, and hence instantly +removed. + +This process, therefore, differs from that with hyposulphite. The +latter acts by dissolving the iodide of silver, the former by +decomposing it. It is necessary not to leave the zinc in contact too +long, or it deposits stains, and in large plates the contact should be +made at the four corners successively, to avoid this accident. + +Gilding Solution.—To one pint of pure rain or distilled water add +fifteen grains of pure chloride of gold, and to another pint add sixty +grains of hyposulphite of soda. When dissolved, pour the gold solution +into the hyposulphite by small quantities, shaking well after each +addition. The soda solution must not be poured into the gold, as the +gold would be immediately decomposed, and the solution turn black, and +be unfit for use. + +Some operators add muriate of potash and other substances, but these do +not possess any advantage except in cases where it is necessary to +bleach the solarized portions of the impression, and when such is the +case, chloride of sodium (common salt) is probably as effective and is +the most convenient. Add about a teaspoonful to two ounces of the +gilding. + +Solution, for Increasing the Brilliancy of the Daguerreotype.—This +solution will have the effect to thoroughly cleanse the surface of the +gilded plate and excite a powerful influence on the general character +of the impression. To a solution of three ounces of water, in which is +dissolved a quarter of an ounce of cyanide of potassium, add one +teaspoonful of a solution containing six ounces of water and half an +ounce of each pure carbonate of potash, alum, common salt, gallic acid, +sulphate of copper, and purified borax. While the plate is wet, pour on +a little, and heat it with a powerful blaze. The effect will be quickly +produced, in from three to fifteen seconds. Rinse and dry, as in the +gilding. + +Bleaching Solution.—Make a saturated solution of muriate of ammonia +(sal ammoniac) in pure water, and filter through paper. Reduce with an +equal quantity of water when used. When the linen or any other portion +of the impression is badly solarized, after removing the coating, rinse +with water; then pour this upon the surface in the same manner as the +gilding solution. If the solarization be very deep, apply the lamp +beneath, and warm the plate a trifle. Now pour off, and, without +rinsing, apply the gilding. The whole operation must be quickly +performed, or the chlorine soon attacks the shades of the picture. When +properly done, however, the solarized parts are restored to a clear, +transparent white. + +Electro, or Cold Gilding.—This process I have adopted, and it produces +exceedingly beautiful impressions for the stereoscope, adding a great +charm to the pleasing effect of that instrument. It also possesses a +pretty and curious effect on views. It is easy of trial, and may be +used by dissolving one gramme of chloride of gold in half a litre of +ordinary water, and thirty grammes of hyposulphite of soda in another +half litre of similar water; then pour the solution of chloride of gold +into that of soda, by little and little, agitating it exactly as in M. +Fizeau’s preparation, of which there is but a variation. + +When you wish to use it, pour some into a plate, or any other vessel of +the same kind, sufficient to cover the proof; then, after having added +to it a drop of ammonia, immerse the plate in it as soon as you take it +out of the mercury-box, after having wiped its back and edges, and +agitate the mixture quickly from right to left, so as to dissolve +rapidly the coating of iodide of silver as usual. As soon as the plate +appears white, cease all rapid motion, but continue to give it a slight +undulating one; for if it were allowed to remain still for only a few +minutes, the proof would be clouded. By little and little, the surface +of the plate takes a yellow tint, which darkens more and more, +approaching to bistre. You stop therefore, at the color you wish; and +when the proof has been washed and dried, in the manner previously +explained, it will be found to be fixed, without any stain, with a +limpid surface, and an extraordinary warm tone. If you were to augment +the proportions of the ammonia or chloride of gold, the operation would +progress much quicker, but then the middle of the proof would be always +much clearer than towards the border. The mixture may be used several +times without being renewed. It does not, however, give such a +beautiful color to the impression as when it is newly prepared. By +communicating to the vessel containing the solution a continual motion, +the impression, when once immersed, will be fixed. During that time, +and while attending to anything else, watch its color; and at the end +of ten minutes or a quarter of an hour, take it out of the bath and dry +it. + +Agent for Neutralizing Bromine, Chlorine, and Iodine Vapors.—Aqua +ammonia, sprinkled about the chemical or coating room, will soon +neutralize all the vapor in the atmosphere of either chlorine, bromine, +or iodine. No operator should be without, at least, a six-ounce bottle +filled with ammonia. A little of its vapor about the camera-box has a +decided and happy effect. Burnt coffee, pulverized, has also the +property of destroying the vapors of the above chemicals, as also +almost any other agent employed about the Daguerreotype room. Its +deodorizing properties are such that if brought in contact with air +filled with the odor of decomposing meat, it will instantly destroy all +disagreeable smell. It can easily be used in the Daguerreotype room by +placing a little of the raw bean, finely pulverized, on an old plate, +and roasting it over the spirit-lamp. + +Buff Dryer.—There are various methods for keeping buffs dry and free +from dust. Some place a sheet of iron against the wall at an angle +sufficient to put a lamp between it and the wall, and then let the buff +rest against the top of the sheet. By this method the buff is for its +full length close to the heated iron, and at the same time exposed to +the heated atmosphere and any dust that may be free. I would recommend +some arrangement by which the buff would be inclosed. I have found the +following to answer the purpose well, which is a box of sheet iron +twenty inches long, eight wide and five high, with one end left open +and the other closed; the cover is made of the same material, with the +edges bent over to go on and off. There are several wires running +through the centre of the sides, which it is necessary to cover with +cloth or paper to absorb all the moisture that may be made by applying +the heat, and the buffs are put in and taken out at the open end. In +order that the heat may be as nearly uniform as possible, an iron bar +one inch wide, eighteen inches long and one half inch thick, is so bent +that the centre is one quarter inch from the bottom of the box, and +that at least two inches of each end come in contact with the bottom; +this being riveted on the bottom, and a lamp with a small blaze applied +to the centre of the bar of iron. This will constitute one of the best +and cheapest buff dryers in use. It may be suspended from the wall by +placing wires around it, or it may stand upon legs. Perhaps a more +convenient plan is to place it under the workbench in a similar +position to a drawer. One precaution is necessary: when first heating +the dryer, apply but a very gentle heat. This will prevent an +accumulation of moisture, which would otherwise pass off in steam, +coming in contact with the buff, thus causing a dampness. Another +caution: never have the temperature of the air in the heater more than +ten degrees above that which surrounds it. + +When wheels are used, they should be encased in a sheet iron or wood +case. All those made for our market are provided in this respect. + +Keeping Buffs in Order.—This is one of the most important objects to +arrest the attention of the operator. Every buff is more or less liable +to get out of order by dust falling upon or coming in contact with the +polishing powder employed in cleaning the plate. The edge of every +plate should be thoroughly wiped and freed from any material that may +adhere while cleaning. I have adopted the following method, which +proves highly successful: + +Rub the buff leather, holding the face down, with the sharp edge of a +pair of shears or a piece of glass. This brings out any portion of the +skin which may have become matted from any moisture, and also takes out +any substance imbedded in it, and prevents it from scratching. Then, +with a stiff brush, rub the buff well, and it will be found to work +well. This same process employ on wheels and hand buffs every morning, +or oftener, as occasion requires. + +Preparing Buffs.—Two of these are necessary. That part of the stick to +be covered should be about eighteen or twenty inches long, and three +wide, and made crowning on the face from one end to the other, about +one half inch. Before covering, these are to be padded with two or +three thicknesses of Canton flannel. The buff should not be too hard, +but padded with flannel, so that by drawing it over the plate, it may +touch across the surface. The only proper material for buffs is +prepared buckskin; and if prepared in a proper manner, this needs +nothing but to be tacked upon the stick. There are several varieties of +wheels employed; the one most generally adopted is Lewis’ patent, which +consists of several varieties of wheels. Any operator can make a +suitable wheel on the same plan of a turning lathe. + +To Clean Buckskins.—When the operator is compelled to purchase an +unprepared buckskin, the following is a good process for cleaning it: +There is always in the buckskin leather that is purchased, more or less +of an oily matter, which is acquired in its preparation, sometimes even +amounting, to a third of its weight. The following is the mode of +ridding it of this noxious ingredient: Dissolve, in about six or seven +quarts of filtered water, about five ounces of potash; when dissolved, +wash with the solution an ordinary buckskin; when it has been well +stirred in the liquid, the water becomes very soapy, owing to the +combination of the potash with the oily matters contained in the skin. +Throw away this solution and use some fresh water without potash and +rather tepid; change it several times until it remains quite limpid. +Then gently stretch the skin to dry in an airy shaded place. When +thoroughly dried, rub it well between the hands. It thus becomes very +pliant and velvet-like. + +Reflectors for Taking Views.—There have been excellent cameras +introduced for taking views, but the time of exposure, which is +increased in proportion to the focal length, is considered an +objection; consequently many adhere to the old plan of using the +speculum, or rather, substitute a mirror. I now have one which I have +used for several years and find it equal to any article of the kind +have ever tried. One is easily made by a tin man, at a trifling +expense. Procure a piece of best plate looking-glass, two and a half by +five inches for a quarter, or four by eight for a half-sized camera; +put a piece of pasteboard of the same size on the back, to protect the +silvering, and stick around the edge in the same manner as in putting +up a picture. Take a sheet of tin for the large size, or a half sheet +for the other; place the glass crosswise in the centre; bend the ends +of the tin over the edge of the glass and turn them back so as to form +a groove to hold the glass, and still allow it to slide out and in. +These ends of the tin must be turned out flaring, that they may not +reflect in the glass. + +Have a tin band about an inch wide made to fit close on the end of the +camera tube; place it on, and taking the tin containing the glass, +bring it to an angle of forty-five degrees with the tube, extending +nearly the whole length of the glass in front of the lenses; lap the +loose ends of the tin on each side of the tin rim, and having your +camera turned on the side to throw the view lengthwise, arrange the +exact angle by examining the image on the ground-glass. When you have +it exactly right, hold it while it is soldered fast to the band. Take +out your glass and stain the tin black, to prevent reflection. + + + + +CHAPTER III. + +CHEMICALS. + + +Bromine and its Compounds—Iodine and its Compounds—Chlorine and its +compounds—Cyanide of Potassium—Hyposulphite of Soda—Hyposulphite of +Gold—Nitric Acid—Nitro-Muriatic Acid—Hydrochloric Acid—Hydrofluoric +Acid—Sulphuric Acid—Accelerating Substances—Liquid Sensitives—Dry +Sensitives, etc., etc. + +BROMINE. + +An article so extensively used in the practice of the Daguerreotypic +art as Bromine, is deserving of especial attention, and accordingly +every person should endeavor to make himself familiar with its +properties and applications. + +History.—This element was discovered in 1826 by M. Balard, in the +mother-liquor, or residue of the evaporation of sea-water. It is named +from its offensive odor (bromos, bad odor). In nature it is found in +sea-water combined with alkaline bases, and in the waters of many +saline springs and inland seas. The salt springs of Ohio abound in the +compounds of bromine, and it is found in the waters of the Dead Sea. +The only use which has been made of bromine in the arts is in the +practice of photography. It is also used in medicine In a chemical +point of view it is very interesting, from its similarity in +properties, and the parallelism of its compounds to chlorine and +iodine. + +Dr. D. Alter, of Freeport, Pa., is the only American manufacturer, and +furnishes all of the “American Bromine.” Yet we understand much +purporting to be of German manufacture is prepared from that made in +Freeport. This is done by individuals in this city, who get well paid +for the deception. + +For the successful application of bromine as an accelerating agent, we +are indebted to Mr. John Goddard of London, who at the time was +associated with Mr. John Johnson, now a resident of this city. + +Preparation.—The mother-liquor containing bromides is treated with a +current of chlorine gas, which decomposes these salts, setting the +bromine free, which at once colors the liquid to a reddish brown color. +Ether is added and shaken with the liquid, until all the bromine is +taken up by the ether, which acquires a fine red color and separates +from the saline liquid. + +{74} + +Solution of caustic potash is then added to the ethereal solution, +forming bromide of potassium and bromate of potash. This solution is +evaporated to dryness, and the salts being collected are heated in a +glass retort with sulphuric acid and a little oxide of manganese. The +bromine is distilled, and is condensed in a cooled receiver, into a red +liquid. + +Properties.—Bromine somewhat resembles chlorine in its odor, but is +more offensive. At common temperatures it is a very volatile liquid, of +a deep red color, and with a specific gravity of 3, being one of the +heaviest fluids known. Sulphuric acid floats on its surface, and is +used to prevent its escape. At zero it freezes into a brittle solid. A +few drops in a large flask will fill the whole vessel when slightly +warmed, with blood red vapors, which have a density of nearly 6.00, air +being one. It is a non-conductor of electricity, and suffers no change +of properties from heat, or any other of the imponderable agents. It +dissolves slightly in water, forming a bleaching solution. + +Chloride of Bromine.—This as an accelerating agent is by many +considered superior {75} to the other Bromide combinations. It can be +readily prepared by passing a current of chlorine through a vessel +containing bromine. A mixture of two parts muriatic acid and one of +black oxide of manganese, should be put into a flask having a bent tube +to conduct the chlorine vapor into the bromine in another vessel. This +last vessel should also be supplied with a bent tube for conducting the +combined vapors with a third vessel or receiver. On the application of +the heat from a spirit lamp to the bottom of the flask, a current of +chlorine gas will be disengaged, and pass into the bromine, when it +readily combines, and gives off a vapor, which, when condensed in the +third vessel, forms a volatile yellowish-red liquid. It is best, even +at ordinary temperature, to place the receiver in an ice bath. For +manner of using, see farther on, under head of Accelerators. + +Bromides.—A bromide treated with oil of vitriol, disengages +chlorohyadic acid; but vapors of bromine are constantly disengaged, at +the same time imparting a brown color to the gas. If the bromide be +treated with a mixture of sulphuric acid, and peroxide of manganese, +bromide is only disengaged. A solution of a bromide gives, with of +nitrate {76} silver, a light yellowish white precipitate of bromide of +silver, which is insoluble in an excess of acid, and readily dissolves +in ammonia. The precipitated bromide is colored by light like the +chloride, but is immediately tinged brown, while the chloride assumes +at first a violet hue. The bromides, in solution, are readily +decomposed and chloride being set free, colors the liquid brown. + +In the whole range of heliographic chemicals there is probably not +another collection less understood and being so productive of +interesting investigation as the bromides. + +Bromide of Iodine.—M. de Valicours furnishes us with the best method +for preparing this mixture: + +“Into a bottle of the capacity of about two ounces, pour thirty or +forty drops of bromine, the precise quantity not being of importance. +Then add, grain by grain, as much iodine as the bromine will dissolve +till quite saturated. This point is ascertained when some grains of the +iodine remain undissolved. They may remain in the bottle, as they will +not interfere with the success of the preparation. + +“The bromide of iodine thus prepared, from its occupying so small a +space, can very easily be carried, but in this state it is much too +concentrated to be used. When it is to be employed, pour a small +quantity, say fifteen drops, by means of a dropping-tube, into a bottle +containing about half an ounce of filtered river water. It will easily +be understood that the bromide of iodine can be used with a greater or +less quantity of water without altering the proportion which exists +between the bromine and iodine.” + +This article forms a very good dry accelerator, and is by some persons +thought superior to all others, as it works with great uniformity, and +is less liable to scum the plate in coating at high temperatures, or +when the thermometer indicates a heat above 60 deg. + +Bromide of Potassium—Is prepared by mixing bromine and a solution of +pure potass together, and evaporating to dryness; it crystallizes in +small cubes, and dissolves readily in water. This agent is extensively +employed in the paper and glass processes. + +Bromide of Lime. This the principal accelerator used in the American +practice, and is the best of all dry combinations at present employed. +There are many reasons why the dry is advantageous; these are too +familiar to repeat. + +“The bromide of lime may be produced by allowing bromine vapor to act +upon hydrate of lime for some hours. The most convenient method of +doing this is to place some of the hydrate at the bottom of the flask, +and then put some bromine into a glass capsule supported a little above +the lime. As heat is developed during the combination, it is better to +place the lower part of the flask in water at the temperature of about +50 deg. Fah.; the lime gradually assumes a beautiful scarlet color, and +acquires an appearance very similar to that of the red iodide of +mercury. The chloro-iodide of lime may be formed in the same manner; it +has a deep brown color. Both these compounds, when the vapor arising +from them is not too intense, have an odor analogous to that of +bleaching powder, and quite distinguishable from chlorine, bromine, or +iodine alone.” + +Farther on, I have given, in connection with accelerators, a process I +adopt, which is far less tedious and equally reliable. + +Bromide of Silver—May be formed by pouring an alkaline bromide into a +solution of nitrate of silver, in the shape of a white, slightly +yellowish precipitate, which is insoluble in water and nitric acid, but +readily dissolves in ammonia and the alkaline hyposulphites. Chlorine +easily decomposes bromide of silver, and transforms it into chloride. + +M. Biot has expressed his opinion, that it is not possible to find any +substance more sensitive to light than the bromide of silver. This is +true to a certain extent, but in combination with deoxidizing agents, +other preparations have a decided superiority over the pure bromide of +silver. + +Bromide of Gold—Is readily prepared by adding a little bromide to the +brown gold of the assayers, and allowing it to remain some time under +water, or assisting its action by a gentle heat. It forms a salt of a +bright crimson color, but in its general properties is precisely +similar to the chloride used in gilding. + +Bromide of Magnesia—Is prepared in the same manner as bromide of lime. + +This mixture is particularly adapted for hot climates, and is used in +this country by some few who regard its use as a valuable secret. + +Bromide of Starch.—This preparation is much used, but not alone. It is +combined with lime by putting about one part in measure of starch to +four of lime. It is prepared by adding bromine to finely pulverized +starch, in the same manner as bromide of lime. (See Accelerators.) + +Experiments with Bromine.—Place in a very flaring wine glass a few +drops (say ten) of bromine, then place a small piece of phosphorus +about one-twentieth of an inch in diameter. Place the latter on the end +of a stick from five to ten feet in length. So place it that the +phosphorus can be dropped into the glass, and in an instant combustion +giving a loud report will be the result. + +b. Expose a daguerreotype plate to the vapor of bromine, it assumes a +leaden-grey color, which, blackens by light very readily. Exposing this +to mercury will not produce any decided action upon the lights. Immerse +it in the solution of the muriate of soda, and the parts unacted upon +by light becomes a jet black, while the parts on which the light has +acted will be dissolved off, leaving a clean coating of silver. This +will be a most decided black picture on a white ground. + +c. Expose an impressioned plate, that has been sufficient time in the +camera to become solarized, to the vapors of bromine, and the +impression will be fully developed and exhibit no signs of +solarization. The exposure over the bromine most be very brief. +Chlorine or iodine will produce the same result. The latter is +preferable. + +Again, should the impressioned plate be exposed too long over the vapor +of bromine, the impression would be rendered wholly insensitive to the +mercurial vapor. Hence this method is resorted to for restoring the +sensibility of the plate when there is reason to believe that the +impression would not be a desirable one; as, for example, if a likeness +of a child be wanted, and it had moved before the plate had been +sufficiently long exposed in the camera, the plate may be restored to +its original sensitiveness by re-coating over bromine, as above, thus +saving the time and labor of re-preparing the plate for the chemicals. + +d. If by accident (we would not advise a trial to any extent of this), +you should inhale a quantity of the vapor of bromine, immediately +inhale the vapor of aqua ammonia, as this neutralizes the dangerous +effect of the bromine vapor. Every operator should be provided with a +bottle of ammonia, as a little sprinkled about the chemical room soon +disinfects it of all iodine or bromine vapor, and also tends to +facilitate the operation in the camera. + +IODINE. + +History of Iodine.—This is one of the simple chemical bodies which was +discovered in 1812 by M. Courtois, of Paris, a manufacturer of +saltpetre, who found it in the mother-water of that salt. Its +properties were first studied into by M. Gay Lussac. It partakes much +of the nature of chlorine and bromine. Its affinity for other +substances is so powerful as to prevent it from existing in an isolated +state. It occurs combined with potassium and sodium in many mineral +waters, such as the brine spring of Ashby-de-la-Zouche, and other +strongly saline springs. This combination exists sparingly in +sea-water, abundantly in many species of fucus or sea-weed, and in the +kelp made from them. It is an ingredient in the Salt Licks, saline, and +brine springs of this country, especially of those in the valley of the +Mississippi. It is sparingly found in fresh-water plants, as well also +in coal, and in combination with numerous other bodies. + +Fermented liquors contain iodine; wine, cider, and perry are more +iodureted than the average of fresh waters. Milk is richer in iodine +than wine; independently of the soil, with which it varies, the +proportion of iodine in milk is in the inverse ratio of the abundance +of that secretion. Eggs (not the shell) contain much iodine. A fowl’s +egg weighing 50 gr. contains more iodine than a quart of cow’s milk. +Iodine exists in arable land. It is abundant in sulphur, iron, and +manganese ores, and sulphuret of mercury: but rare in gypsum, chalk, +calcareous and silicious earths. Any attempt to extract iodine +economically should be made with the plants of the ferro-iodureted +fresh waters. Most of the bodies regarded by the therapeutists as +pectoral and anti-scrofulous are rich in iodine. + +It is probably to the application of this body that we owe the +discovery of the daguerreotype. There is no record of the precise date +when Daguerre commenced experimenting with iodine, but by the published +correspondence between him and M. Neipce, his partner, it was previous +to 1833. There is no doubt, however, that the first successful +application was made in 1838, as the discovery was reported to the +world early in January, 1839. + +Preparation.—Iodine is mostly prepared from kelp, or the half vitrified +ashes of seaweed, prepared by the inhabitants of the western islands, +and the northern shores of Scotland and Ireland. It is treated with +water, which washes out all the soluble salts, and the filtered +solution is evaporated until nearly all the carbonate of soda and other +saline matters have crystallized out. The remaining liquor, which +contains the iodine, is mixed with successive portions of sulphuric +acid in a leaden retort, and after standing some days to allow the +sulphureted hydrogen, etc., to escape, peroxide of manganese is added, +and the whole gently heated. Iodine distills over in a purple vapor, +and is condensed in a receiver, or in a series of two-necked globes. + +Properties.—Iodine is solid at the ordinary temperature, presenting the +appearance of dark-grey or purple spangles, possessing a high degree of +metallic lustre. It somewhat resembles plumbago, with which it is +sometimes diluted, particularly when it is fine. Operators should +endeavor to secure the larger crystals. It melts at 224.6 deg., forming +a brown or nearly black liquid. It boils at about 356 deg., and emits a +very deep violet colored vapor. It gives off a very appreciable vapor, +sufficient for all purposes of forming the iodide of silver on the +daguerreotype plate, at a temperature of 45 deg. or even lower. Iodine +crystallizes readily. Every operator has found upon the side of the jar +in his coating-box, perfectly regular crystals, deposited there by +sublimation. + +Water dissolves but a small proportion of iodine, requiring 7000 parts +of water to dissolve one of iodine, {85} or one grain to the gallon of +water. Alcohol and ether dissolve it freely, as does a solution of +nitrate or hydrochlorate of ammonia and of iodides. + +The density of solid iodine is 4.95; that of its vapor 8.716. It +greatly resembles chlorine and bromine in its combinations, but its +affinities are weaker. It does not destroy the majority of organic +substances, and vegetable colors generally resist its action. It +combines with several organic substances, imparting to them peculiar +colors. It colors the skin brown, but the stain soon disappears. + +Chloride of Iodine—Is formed by passing chlorine into a bottle +containing some iodine. This can be readily done by pouring one ounce +and a half of muriatic acid upon a quarter of an ounce of powdered +black oxide of manganese, and heat it gradually in a flask, to which is +adapted a bent glass tube. This tube must connect with the bottle +containing the iodine, and the yellowish-green gas disengaged will +readily combine with the iodine, forming a deep red liquid, and the +operation is complete. The use of chloride of iodine will be referred +to in connection with the Accelerators. + +{86} + +Iodides.—The iodide treated with the oil of vitriol, instantly produces +a considerable deposit of iodine; and if the mixture be heated, intense +violent vapors are disengaged. The reaction is due to the decomposition +of oil of vitriol by iodohydric acid, water and sulphurous acid being +formed, and iodine set free. The iodides in solution are decomposed by +chlorine, iodine being precipitated, the smallest quantity of which in +solution is instantly detected by its imparting to starch an intensely +blue color. + +Iodide of Potassium.[4]—This compound is easily made in the following +manner: Subject to a moderate heat a mixture of 100 parts of iodine, 75 +of carbonate of potash, 30 of iron filings, and 120 parts of water. +This mass must be thoroughly dried and then heated to redness; the +resulting reddish powder is to be washed with water, and the solution +obtained filtered, and evaporated to dryness. It is found that 100 +parts of iodine yield 135 parts of very white, but slightly alkaline, +iodide of potassium. + + [4] I shall present the preparation of only a few iodides, and such as + are more intimately connected with the Daguerreotype. + +Experiment.—On projecting dry pulverized iodide of potassium into fused +anhydrous phosphoric acid, a violent disengagement of iodine takes +place, attended by a transient ignition; fused hydrate of phosphoric +acid liberates iodine abundantly from iodide of potassium; this +reaction is accompanied by the phenomenon of flame and formation of a +considerable quantity of hydriodic acid. + +Iodide of Mercury.—For the preparation of iodide of mercury, Dublanc +recommends to cover 100 grms. of mercury with 1 kilogrm. of alcohol, to +add 124 grms. of iodine gradually in portions of ten grms., and +agitating between each fresh addition, until the alcohol becomes +colorless again. After the addition of the last 4 grms. the alcohol +remains colored, the whole of the mercury having become converted into +iodide. The resulting preparation is washed with alcohol; it is +crystalline and of a hyacinth color. + +Iodide of Silver.—This compound is formed upon every plate upon which a +Daguerreotype is produced. The vapor of iodine coming in contact with +the silver surface, forms an iodide which is peculiarly sensitive to +light. + +The various colors produced are owing to the thickness of the coating, +and the maximum sensibility of the coating, as generally adopted, is +when it assumes a deep yellow, or slightly tinged with rose color. + +This compound is largely employed in most photographic processes on +paper, and may be easily prepared by the following formula: By adding +iodide of potassium to a solution of nitrate of silver, a +yellowish-white precipitate of iodide of silver is obtained, which is +insoluble in water, slightly soluble in nitric acid, and soluble in a +small degree in ammonia, which properties seem easily to distinguish it +from the chloride and bromide of silver. Chlorine decomposes it and +sets the iodine free, and chlorohydric acid converts it into a +chloride. It fuses below a red heat. Although the effect of light on +the iodide is less rapid than on the chloride, the former sooner +turning black, assuming a brown tinge; but when in connection with +gallic acid and the ferrocyanate of potash, it forms two of the most +sensitive processes on paper. + +Iodide of silver dissolves easily in a solution of iodide of potassium, +and the liquid deposits in evaporation crystals of a double iodide. + +Iodide of Gold.—If a solution of potassium be added to a solution of +chloride of gold, a precipitate of iodide of gold takes place, soluble +in an excess of the precipitate. A little free potash should be added +to combine with any iodide that may chance to be set free by the +chloride of gold. + +Iodide of Lime is prepared by adding iodine to hydrate of lime (which +will be referred to farther on) until the mixture assumes a light +yellow shade, when wanted for combinations with accelerators, or to a +dark brown when employed for the first coating. This latter mixture has +been sold in our market under the name of “Iodide of Brome.” + +Iodide of Bromine.—(See page 76.) + +Experiments with Iodine.—Place a plate which has been exposed in the +camera over the vapor of iodine for a very brief period, and it will +present the appearance of the impression having been solarized. + +b. Upon a Daguerreotype plate, from which an impression has been +effaced by rubbing or otherwise, the picture may be made to reappear by +merely coating it over with iodine. + +c. Place in a vessel a little water, into which put the smallest +possible quantity of free iodine and add a little starch, and the +liquid will instantly assume a blue color. Advantage is taken of this +fact in the laboratory to detect the presence of iodine in liquids. The +starch should be dissolved in boiling water and allowed to cool. There +are numerous other interesting experiments that can be performed by the +aid of iodine, but it is unnecessary here to consume more space. + +CHLORINE. + +History.—The Swedish chemist, Scheele, in 1774, while examining the +action of hydrochloric acid on peroxide of manganese, first noticed +this element. He called it dephlogisticated muriatic acid. It was +afterwards, by the French nomenclaturists, termed oxygenated muriatic +acid, conceiving it to be a compound of oxygen and muriatic acid. This +view of its notice was corrected by Sir H. Davy (in 1809), who gave it +the present name. In 1840-41, this gas vas employed for accelerating +the operation of light upon the iodized Daguerreotype plate. John +Goddard, Wolcott & Johnson, Claudet, Draper, Morse and others, were +among the first made acquainted with its use. Count Rumford, Ritter, +Scheele, Seebert and others, experimented with chlorine in regard to +its effect when exposed to the action of light in combination with +silver. In 1845, M. Edward Becquerel announced that he had “been +successful in obtaining, by the agency of solar radiations, distinct +impressions, of the colors of nature.” + +On the 4th of March, 1851, Neipce, St. Victor, a former partner of +DAGUERRE, announced that he had produced “all the colors by using a +bath of bichloride of copper, and that a similar phenomenon occurs with +all salts of copper, mixed with chlorine.” + +Preparation.—This is easily accomplished by putting about two parts of +hydrochloric (muriatic) acid on one of powdered black oxide of +manganese, and heating it gradually in a flask or retort, to which may +be adapted a bent glass tube. A yellowish-green gas is disengaged, +which being conducted through the glass tube to the bottom of a bottle, +can readily be collected, being much heavier than the air, displaces it +completely and the bottle is filled (which can be seen by the green +color); a greased stopper is tightly fitted to it, and another bottle +may be substituted. + +In all experiments with chlorine, care should be taken not to inhale +the gas! + +Properties.—Chlorine is a greenish-yellow gas (whence its name, from +chloros, green), with a powerful and suffocating odor, and is wholly +irrespirable. Even when much diluted with air, it produces the most +annoying irritation of the throat, with stricture of the chest and a +severe cough, which continues for hours, with the discharge of much +thick mucus. The attempt to breathe the undiluted gas would be fatal; +yet, in a very small quantity, and dissolved in water, it is used with +benefit by patients suffering under pulmonary consumption. + +Under a pressure of about four atmospheres, it becomes a limpid fluid +of a fine yellow color, which does not freeze at zero, and is not a +conductor of electricity. It immediately returns to the gaseous state +with effervescence on removing the pressure. + +Water recently boiled will absorb, if cold, about twice its bulk of +chlorine gas, acquiring its color and characteristic properties. The +moist gas, exposed to a cold of 32 deg., yields beautiful yellow +crystals, which are a definite compound of one equivalent of chlorine +and ten of water. If these crystals are hermetically sealed up in a +glass tube, they will, on melting, exert such a pressure as to liquefy +a portion of the gas, which is distinctly seen as a yellow fluid, not +miscible with the water which is present. Chlorine is one of the +heaviest of the gases, its density being 2.47, and 100 cubic inches +weighing 76.5 grains. + +Chlorine Water.—This combination, which is used in conducting M. +Neipce’s process, can be readily prepared by conducting the gas into a +bottle containing distilled water. One part water dissolves two parts +of chlorine. + +Chlorides.—The metallic chlorides are nearly all soluble in water; that +of silver and protochloride of mercury being the only exceptions. A +metallic chloride, treated with oil of vitriol, disengages chlorohydric +acid. Heated with a mixture of peroxide of manganese and sulphuric +acid, chlorine is given off, which is easily recognized by its odor and +other physical properties. + +The chlorides dissolve in water; give with nitrate of silver, a white +precipitate, even in highly diluted solutions, becoming violet colored +and finally black when exposed to the light. The rapidity of the change +of color is proportioned to the intensity of the light. It is insoluble +in nitric acid, but readily soluble in ammonia; it fuses without +decomposition, forming, when cold, a tough, horny mass, and is reduced +by hydrogen and by fusion with carbonate of soda, or with resin. + +Chloride of Bromine. (See page 74.) + +Chloride of Iodine. (See page 85.) + +Chloride of potassium.—or (Muriate of Potassa).—Dissolve half an ounce +of carbonate of potassa in water, and neutralize with muriatic acid. +Upon concentrating the solutions, cubic crystals will be obtained, +having a taste similar to common salt. They consist of potassium and +chloride, and when dissolved in water they may be regarded as muriate +of potassa. + +Chloride of Lime.—Mix half an ounce of slacked lime (hydrate of lime) +with six ounces of water, and conduct into this milk of lime, with +frequent agitation, as much chlorine gas as will evolve from two ounces +of muriatic acid and half an ounce of black oxide of manganese. The +liquid clarifies by standing; may be regarded as a solution of chloride +of lime, and must be protected from the air and light. It may also be +made without putting in the water with the hydrate of lime, by merely +passing the chlorine into the hydrate of lime. This last is by some +used in preparations for accelerating the operation of taking +Daguerreotypes, but when used for this purpose it is in small +quantities. + +Chloride of Calcium.—To one part of water add two parts of muriatic +acid, and add pieces of common chalk until effervescence ceases; then +filter through cotton cloth and evaporate it by placing it in all +earthen or porcelain dish, over a slow fire, to the consistency of a +syrup. When cooling, large prismatic crystals of chloride of calcium +are formed. These must be quickly dried by pressing between folds of +blotting paper and kept carefully excluded from the air, as it readily +attracts hydrogen. For most daguerreotype purposes, the syrup may be at +once evaporated to dryness. This is frequently placed in the iodine +coating box for the purpose of keeping the atmosphere dry. It is so +easily made that every operator can provide himself with it in a short +time, and at little expense. + +Chloride of Gold.—Is prepared by dissolving gold in aqua regia, a +composition of one part of nitric to two parts of muriatic acid. Gold +foil is the best for our purposes; coin, however, answers, in most +cases, for the daguerreotype operator, as the alloy, being so slight is +not noticed in the gilding process. When the latter is used, it will +facilitate the operation to beat it out, forming a thin sheet, and then +cutting in small strips. Where purity is required, foil is better. The +gold is placed in three or four times its own weight of the above +acids. For this purpose, an evaporating dish is best (a common saucer +will do); a moderate heat may be applied to favor the action. The +mixture should be stirred often with a glass rod; care should be +observed not to apply too much heat, for at a temperature of about 300 +deg. the chlorine would be expelled and leave a metallic precipitate, +which would require re-dissolving. Acid may at any time be added if +necessary to dissolve the gold, but it is advisable to add as little +excess as possible, as it would require more time to evaporate. After +all the gold has dissolved, and the liquid assumes a deep red color, +the solution should be allowed to cool, being stirred nearly all the +time. This salt is of a reddish-brown color. It is rarely we find in +our market good chloride of gold, as common, salt is used for the bulk; +and when the bottles are labelled “15 grains,” “20 grains,” nine-tenths +do not in reality contain exceeding five grains of chloride of gold. +The salt is mixed with the above solution when it is cooling, and gives +bright yellow crystals, which some of our uninformed operators conceive +to be the best quality. + +Chloride of Silver.—(Oxide of Silver.)—Take any quantity of silver coin +or other silver, roll or hammer it thin; cut in small pieces. This in +order to save time. Put the silver in a glass or earthen vessel +(Florence flask is best); pour in nitric acid and water, about three +parts of the former to one of the latter. The operation of cutting up +the silver may be facilitated by applying a gentle heat. This blue +solution consists of oxide of silver and oxide of copper, both combined +with nitric acid. Should the operator wish a pure solution of silver, +which, however, is not always used, he may obtain it in the following +manner: + +To separate the two metals contained in the above solution from each +other, put some bright copper coins into the solution and set it aside +in a warm place for three or four days, occasionally giving it a +circular motion. The separated laminae are pure silver, which is to be +digested with ammonia until it ceases to be colored blue. The silver, +after being washed and dried, is again dissolved in nitric acid, and +the liquid, diluted with water, is kept as solution, of silver. + +Either of the above solutions (the one of oxide of silver and copper, +and the pure silver solution) may be prepared for use by putting them +in a bottle, with a quantity of water, and adding common fine salt, you +obtain a white curdy precipitate of chloride of silver. No matter how +much salt is used, provided enough be added to throw down all the +chloride of silver. This solution should be well agitated and then +allowed to stand for a few minutes; thus the white precipitate is in +the bottom of the bottle. When the water has become clear, pour it off +with care, leaving the sediment behind, then add a fresh quantity of +clean water, shake, let settle, and pour off as before. Repeat the same +for several times, and the excess of salt will disappear, leaving the +white precipitate, which may be drained of the water and dried in the +dark, and kept free from light and air. + +CYANIDE OF POTASSIUM. + +Cyanide of Potassium.—This important article is worthy the undivided +attention of every Daguerreotypist. I here give Mr. Smee’s process for +its preparation. This is from that author’s work entitled, “Electro +Metallurgy,” American edition: + +“The cyanide of potassium, so often alluded to while treating of the +metallo-cyanides, may be formed in several ways. It may be obtained by +heating to a dull redness the yellow ferrocyanate of potash, in a +covered vessel, filtering and rapidly evaporating it. The objection to +this method, however, is that without great care the whole of the +ferrocyanate is not decomposed, a circumstance which much reduces its +value for electro-metallurgy. By boiling, however, the ignited residue +with spirits of wine this difficulty is said to be overcome, as the +ferrocyanate is absolutely insoluble in that menstruum, while the +cyanuret, at that heat, freely dissolves, and is as easily re-deposited +on cooling. + +“There is, however, a much better process by which this salt may be +formed, viz. by simply transmitting hydrocyanic acid through potassium. +Although the modes of making this acid are very numerous, there is but +one which is likely to be employed on a very large scale, and that is +its formation from the yellow ferrocyanate by means of sulphuric acid. +This process is performed as follows: any given weight of the yellow +salt is taken and dissolved in about five times its weight of water; +this is placed in a retort, or some such analogous vessel, to which is +then added a quantity of strong sulphuric acid, twice the weight of the +salt, and diluted with three or four times its quantity of water. A +pipe is carried from the neck of the retort to the receiving bottle, +which should be kept as cool as possible. + +“For small operations, those invaluable vessels, Florence flasks, +answer well: a bent tube being connected at one end to its month, the +other passing into the second vessel; heat should be cautiously applied +by means of an Argand lamp, a little vessel of sand being placed under +the flask, which helps the acid to decompose the salt. Prussic acid is +then generated and passes through the tube to the recipient vessel, +which is to be charged with liquor potassae. + +“When the potash is saturated, the operation is completed. The Germans +recommend a strong, alcoholic solution of potassa to be used in the +second vessel, for in this case, the hydrocyanic or prussic acid +combines with the potassa, forming a hydrocyanate of potassa, or, the +water being abstracted, the cyanuret of potassium, which spontaneously +precipitates, on the saturation of the fluid, the cyanuret, being +insoluble in strong alcohol. The ferrocyanate of potash may be +considered as containing three equivalents of hydrocyanic acid, two of +potash and one of iron; but, unfortunately, we can only obtain half the +acid from the salt, owing to the formation of a compound during its +decomposition which resists the action of the acid. The decomposition +of this salt taking 2 equivalents or 426 grains (to avoid fractions) +would afford 3 equivalents or 81 grains of hydrocyanic, or prussic +acid, capable of forming 198 grains of cyanuret of potassium, while in +the retort there would remain 384 grains or 3 equivalents of bisulphate +of potash, and 1 equivalent or 174 grains of a peculiar compound, said +to contain 3 equivalents of cyanogen, 1 of potassium, and one of iron +(Pereira). It is manifest that, but for this later compound, we might +double the quantity of hydrocyanic acid from the yellow salt.” + +The decomposition just described is the one usually received; but too +much reliance must not be placed on its accuracy, for the analysis of +the several compounds is too difficult for the results to be fully +admitted. The residue left in the retort speedily turns to one of the +blues, identical with, or allied to, Prussian blue. This is at best a +disagreeable process to conduct, for the hydrocyanic acid formed +adheres so strongly to the glass, that, instead of being freely given +off, bubbles are evolved suddenly with such explosive violence as +occasionally to crack the vessel. This may be remedied as far as +possible by the insertion of plenty of waste pieces of platinum—if +platinized, so much the better, as that facilitates the escape of the +gas. The heat should be applied to every part of the vessel, and the +flame should not be allowed to play upon one single part alone. Large +commercial operations are performed in green glass or stone-ware +retorts. + +“Now for one word of advice to the tyro: Remember that you are working +with prussic acid; therefore, never conduct the process in a room, the +fumes being quite as poisonous as the solution of the acid itself; +moreover, have always a bottle of ammonia or chlorine by your side, +that should you have chanced to inhale more than is pleasant, it will +be instantly at hand to counteract any bad effects. It is stated by +Pereira, that a little sulphuric acid or hydroferrocyanic acid passes +to the outer vessel, but probably the amount would be of no consequence +for electro-metallurgy, otherwise, it might be as well to use a +Woulfe’s apparatus, and discard the salt formed in the first vessel. To +the large manufacturer it may be worth considering whether some other +metallo-cyanuret, formed in a similar manner to the ferrocyanuret, +might not be more advantageously employed, because the residue of the +process last described contains a large quantity of cyanogen which the +acid is unable to set free. + +“There are other modes of procuring prussic acid, besides the one which +has been so tediously described; but these are found to be more +expensive. The only one which I shall now notice is the process by +which it is obtained from bicyanide of mercury. The bicyanide of +mercury itself is formed when peroxide of mercury is digested with +Prussian blue, the peroxide of mercury abstracting the whole of the +cyanogen from the blue, and leaving the oxides of iron at the bottom of +the vessel. The solution may be evaporated to dryness, and one part of +the salt dissolved in six of water; one part of muriatic acid, sp. gr. +1.15, is then added, and the solution distilled, when the whole of the +hydrocyanic acid passes over, and by being conducted into a solution of +potassa, as in the former process, forms cyanuret of potassium. This +process, though easier than the first described, is rather given as a +resource under peculiar circumstances than as one to be adopted by the +large manufacturer. The expense is the only objection, but in a small +quantity this cannot be a consideration. + +“In giving this very rough outline of the general mode of forming +salts, the minutiae necessary for chemical work have altogether been +avoided, and those parts alone are entered upon which are more +immediately necessary for the electro metallurgist to know and practice +for himself. This will account for the long description of the cyanuret +of potassium, while the preparation of the equally important and even +more used acids, the sulphuric, muriatic, etc., commonly found in +commerce, are altogether neglected. + +“In using solutions of cyanide of potassium, the workman should not +immerse his arms into them, otherwise it occasionally happens that the +solution produces very troublesome eruptions over the skin.” + +HYPOSULPHITE OF SODA. + +Hyposulphite of Soda.—This salt forms one of the important chemicals +for the Daguerreotype operator. Its application to this art is of an +interesting nature. It is used to dissolve the sensitive salt of silver +which remains unchanged during the exposure in the camera. It has the +property of readily dissolving the chloride, bromide and iodide of +silver. It should be pure and free from sulphuret of sodium; should +this last be present, it will cause brown spots of sulphurated silver +upon the Daguerreotype impression. This annoyance is a great source of +complaint from many operators, and ever will be, so long as it is +prepared by men who have no reputation to lose, and whose eyes are +blinded by the “Almighty Dollar.” + +A good article may be prepared as follows: + +“Mix one pound of finely pulverized carbonate of soda with ten ounces +of flowers of sulphur, and heat the mixture slowly in a porcelain dish +till the sulphur melts. Stir the fused mass, so as to expose all its +parts freely to the atmosphere, whereby it passes from the state of a +sulphuret, by the absorption of atmospheric oxygen, into that of a +sulphite, with the phenomenon of very slight incandescence. Dissolve in +water, filter the solution, and boil it immediately along with flowers +of sulphur. The filtered concentrated saline liquid will afford, on +cooling, a large quantity of pure and beautiful crystals of +hyposulphite of soda.” + +Hyposulphite of Gold.—This compound salt is by a few considered +preferable to the chloride of gold, but our experience has induced us +to use the latter, believing we are enabled to produce a more brilliant +and warm-toned impression with it. When the hyposulphite of gold is +used in gilding, it requires less heat and a longer application, as +there is some danger of producing a glossy scum over some parts of the +surface of the plate. I prepare this salt as follows: + +Dissolve one part chloride of gold and four parts hyposulphite of soda +in equal quantities of distilled water: pour the gold into the +hyposulphite solution, in the same manner as in mixing the gilding +solution; let it stand until it becomes limpid; filter and evaporate to +dryness. Re-dissolve and add a few grains of burnt alum. + +After standing a few hours, filter and evaporate again. If not +sufficiently pure, repeat the crystallization until it is so. For +gilding, dissolve in water and use in the same manner as the common +gilding solution. + +N.B.—The four following mixtures were employed in Neipce’s process in +his earliest experiments: + +Aqueous Solution of Bichloride of Mercury.—Eight grains of bichloride +of mercury in 10,000 grains of distilled water. + +Solution of Cyanide of Mercury.—A flask of distilled water is saturated +with cyanide of mercury, and a certain quantity is decanted, which is +diluted with an equal quantity of distilled water. + +Acidulated White Oil of Petroleum.—This oil is acidulated by mixing +with it one tenth of pure nitric acid, leaving it for at least 48 +hours, occasionally agitating the flask. The oil, which is acidulated, +and which then powerfully reddens litmus paper, is decanted. It is also +a little colored, but remains very limpid. + +Solution of Chloride of Gold and Platinum.—In order not to multiply the +solutions, take the ordinary chloride of gold, used for fixing the +impressions, and which is composed of 1 gramme of chloride of gold and +50 grains of hyposulphate of soda, to a quart of distilled water. + +With respect to chloride of platinum, 4 grains must be dissolved in 3 +quarts of distilled water; these two solutions are mixed in equal +quantities. + +Acids.—I shall not go into the preparations of the various acids +employed in the Daguerreotype. This would be useless to the operator, +as there are few, if any, that it would be advisable to prepare. It is +only necessary for the experimenter to be made acquainted with their +properties, and this in order to prevent any haphazard experiments, +which are too common among operators. Any person who may be desirous to +try an experiment, should first study the agents he wishes to employ. +By so doing much time and money will be saved; while the searcher after +new discoveries would rarely become vexed on account of his own +ignorance, or be obliged to avail himself of the experience of others +in any department of science. + +Nitric Acid—Exists in combination with the bases, potash, soda, lime, +magnesia, in both the mineral and vegetable kingdoms, and is never +found insoluble. It has the same constituents as common air, but in +different proportions. The strongest nitric acid contains in every +pound, two and a quarter ounces of water. Pure nitric acid is +colorless, with a specific gravity of 1.5, and boiling at 248 deg.. It +is a most powerful oxidizing agent, and is decomposed with more or less +rapidity, by almost all the metals, to which it yields a portion of its +oxygen. + +The nitric acid of commerce, is generally the article used by the +Daguerreotypist. This usually contains some chlorine and sulphuric +acid. It is obtained by the distillation of saltpetre with sulphuric +acid. It is employed in the Daguerreotype process for dissolving +silver, preparing chloride or oxide, nitrate of silver, [the former +used in galvanizing,] and in combination with muriatic acid for +preparing chloride of gold, used in gilding. It is also used by some +for preparing the plate. + +Acidulated Solution.—This solution is used for cleaning the surface of +the Daguerreotype plate. It has the property of softening the silver, +and bringing it to a state in which it is very susceptible of being +either oxidized or iodized, hence it contributes to increase the +sensibility of the plate. The proportions are to one drop of acid add +from 15 to 20 drops of water, or make the solution about like sharp +vinegar to the taste. + +Nitro-Muriatic Acid.—Aqua Regia is a compound menstruum invented by the +alchemists for dissolving gold. It is composed of colorless nitric acid +(aqua-fortis) and ordinary muriatic acid; the mixture is yellow, and +acquires the power of dissolving gold and platinum. These materials are +not properly oxidized; it nearly causes their combination with +chlorine, which is in the Muriatic acid. + +Hydrochloric Acid (Muriatic Acid).—This acid forms a valuable addition +to the chemicals employed by the practical Daguerreotypist. This acid +is formed by acting upon common salt (which is chloride of sodium) by +concentrated sulphuric acid. The water of the acid is decomposed, and +its hydrogen combines with the chloride of the salt to form muriatic +acid, and this unites with the sulphuric acid to form sulphate of soda; +60 parts of common salt and 49 parts of concentrated sulphuric acid, +afford, by this mutual action, 37 parts of muriatic acid and 72 parts +of sulphate of soda. The muriatic acid of commerce has usually a +yellowish tinge, but when chemically pure it is colorless. The former +is commonly contaminated with sulphurous acid, sulphuric acid, +chlorine, iron, and sometimes with arsenic. + +Muriatic acid, from the fact of the presence of the chlorine, is used +in the Daguerreotype process for dissolving gold, and in combination +with various accelerators. Its presence can be detected by ammonia. A +strip of paper dipped in this and waved to and fro will emit a thick +white smoke if the acid vapor be in the atmosphere. The ammonia +neutralizes the acid fumes. By reversing the experiment we can +determine whether vapor of ammonia be in the air, and also deprive +these suffocating and dangerous gases of their injurious properties, +and remove them from the air. Every Daguerreotype operator should be +furnished with, at least, a six ounce bottle of aqua ammonia. Its +operation is very nearly the same on bromine and iodine vapor. + +Hydrofluoric Acid (Fluorohydric Acid).—This acid is used to form some +of the most volatile and sensitive compounds employed in the +Daguerreotype. It is one of the most dangerous bodies to experiment +with: it is volatile and corrosive, giving off dense white fumes in the +air. It combines with water with great heat. At 32 deg. it condenses +into a colorless fluid, with a density 1.069. It is obtained from +decomposition of fluorspar by strong sulphuric acid. It readily +dissolves the silica in glass, and consequently cannot be kept in a +vessel of that material. It is prepared and kept in lead. It is +employed in accelerators on account of its fluorine. + +One small drop on the tongue of a dog causes death. The operator who +wishes to use it should pour some of the liquid for which he intends it +into a graduate, or other vessel, and then add the desired quantity of +acid. If by accident any of the spray should fall upon the skin, it +should at once be copiously drenched with water. + +Sulphuric Acid.—There are two sorts of this acid: one is an oily, +fuming liquid; this is made in Nordhausen, in Saxony, and is commonly +called “Nordhausen sulphuric acid,” or oil of vitriol. The other which +is the kind used in connection with the Daguerreotype, is common +sulphuric acid. It is somewhat thinner, and when undiluted is not +fuming. This acid may be obtained in a solid and dry state, called +anhydrous sulphuric acid. + +The common sulphuric acid is made by burning sulphur, which forms +sulphurous acid. To convert this into sulphuric acid and gain more +oxygen, nitric acid, which is rich in that body, is added. It forms a +limpid, colorless fluid, of a specific gravity of 1.8. It boils at 620 +deg.; it freezes at 15 deg. It is acrid and caustic, and intensely acid +in all its characters, even when largely diluted. + +Its attraction for basis is such that it separates or expels all other +acids, more or less perfectly, from their combinations. Its affinity +for water is such that it rapidly absorbs it from the atmosphere, and +when mixed with water much heat is evolved. It acts energetically upon +animal and vegetable substances, and is a poisonous, dangerous +substance to get on the skin. It is a powerful oxidizing agent; hence +its use in the galvanic battery, for which purpose it is mostly used by +the Daguerreotypist. The fumes of this being so much more offensive +than nitric acid, the latter is sometimes used. It is also employed in +some of the more sensitive accelerators. + +ACCELERATING SUBSTANCES. + +Remarks on the Accelerating substances Used in the Daguerreotype.—I +have now arrived at a point in this work, where the eye of the +Daguerreotype public will intently search for something new. This +search will prove in vain, at least so far as regards those who have +enjoyed and embraced the opportunities for studying the principles of +our art. Every experienced operator has in a degree become familiar +with the mechanical uses of all the agents employed, while I fear but +few understand the properties, and laws governing those properties, +which are so indispensable to produce an image impressed upon the +silver surface. + +There are three substances which form the bases for producing a +Daguerreotype; silver, iodine and bromine. Each forms a separate body +which is indispensable to the operators success as the art is now +practiced in America. With these three, compounds of great variety are +formed. + +The silver surface is first thoroughly cleaned and freed from all +organic matter, then exposed to vapor of iodine, producing an iodide of +silver. The plate upon which is this salt, is again exposed to the +vapor of bromine, forming a bromo-iodide of silver, a salt also. + +As most of the various accelerators are compounds of bromine, with +either chlorine or fluorine combination, they partake somewhat of the +nature of these latter, giving results which can be detected by the +experienced operator. Thus muriatic acid is added for its chlorine, +which can generally be detected by the impression produced, being of a +light, soft, mellow tone, and in most cases presenting a brilliant +black to that colored drapery. Those who wish to experiment with agents +for accelerating substances, should first study to well understand +their peculiar nature and properties; as well, also, to endeavor to +find out what will be the probable changes they undergo in combination +as an accelerator. This should be done before making the experiments. +From the foregoing it will be seen that numerous compounds are formed +from the same basis, and, consequently, it would be a waste of time and +a useless appropriation to devote more of our space than is necessary +to give the principal and most reliable combination. + +In America, the words “Quick” and “Quick Stuff,” are more generally +used for and instead of the more proper names, “Sensitives,” or +“Accelerators,” etc. As it has by use become common, I frequently use +it in this work. + +Liquid Accelerator, No. 1.—This mixture was used by me in 1849, and is +given as it appeared in my “System of Photography,” published at the +above date: + +Take pure rain or distilled water, one quart, filter through paper into +a ground stopper bottle, and add, for warm weather, one and a half +ounce chloride of iodine; or for cold, one ounce; then add one ounce +bromine, and shake well. Now with care not to allow the vapor to +escape, add drop by drop, thirty drops of aqua ammonia, shaking well at +each drop. Care must be taken not to add more at a time, as it evokes +too much heat. This mixed, in equal proportions with John Roach’s +quick, forms an excellent chemical combination. For this purpose, take +one and a half ounce of each, to which add ten ounces water, for warm +weather, or from six to seven for cold. Pour the whole into a large +box, and it will work from two to four months. I am now using (1849) +one charged as above which has been in constant use for three months, +and works uniformly well. The above is right for half or full size +boxes, but half of it would be sufficient for a quarter size box. + +Coat to the first shade of rose over iodine, change to a deep rosy red +over quick, and black about one tenth the first. + +I would not now recommend the addition of “John Roach’s quick,” as I +believe equally good results can be produced without it. This liquid is +now used by many, and is very good for taking views. + +Lime Water Quick.—This mixture is more used at present than all the +other liquids ever introduced. It produced the most uniform results, +giving the fine soft tone so characteristic in pictures produces from +accelerators containing chlorine. To one quart of lime water (this can +be had of any druggist) add one and a half ounce of pulverized alum. +This should be shook at intervals for twenty—four hours; then add one +ounce of chloride of iodine and three fourths ounce of bromine. + +Lime Water.—This is easily prepared by putting lime into water, say a +piece of quick-lime about the size of an egg into one quart of water. +This should be shook occasionally for two or three days and allowed to +settle, when the water can be poured off and used. + +Use.—To one part of quick add six parts of water; coat to a light +yellow over the iodine, to a rose color over the quick, and recoat +about one tenth. The above coating may be increased or diminished, it +matters not, so that there is not too much, and the proper proportions +are preserved. Some add to the above a small quantity of magnesia, say +about a teaspoonful to the quart of liquid. + +Liquid Accelerator, No. 2.—The following was for a long time used by +one of the first houses in the United States, and probably was one of +the first liquids ever used. It produces a fine-toned picture, but is +not considered as sure as the lime water quick: + +Take rain water one quart, add pulverized alum until it is a little +sour to the taste, and a small piece, say one half inch square, of +magnesia. Filter through paper, and add chloride of iodine one half +ounce, bromine sufficient to take it up, which is a little less than +half an ounce. + +Charge with one of quick to six of water; coat over iodine to a soft +yellow, nearly, but not quite, bordering on a rose; over quick to a +dark purple, or steel, and back one sixth to one tenth. + +Wolcott’s American Mixture.—Van Loan Quick.—This mixture was first +formed and used by T. Wolcott & Johnson and gained great celebrity for +its productions. I have now a bottle hermetically sealed that contains +about a half ounce of this mixture prepared in 1841 by John Johnson, +now a resident of this city, and the former partner of Mr. Wolcott. The +preparation of this mixture, as furnished by Mr. Johnson himself, is +given as follows: + +“One part of bromine, eight parts of nitric acid, sixteen parts of +muriatic acid, water one hundred parts. This mixture should be allowed +to stand for several days; it improves by age. + +“Use.—A few drops say, 6 to 12, of this mixture, should be put into +about 6 or 8 ounces of water; it will require frequent replenishing by +the addition of a few more drops. The plate should be coated over the +dry iodine to a red just bordering on a slate, and then exposed to the +mixture only sufficiently long to change the color. If this is not done +in less than six seconds it is not strong enough. Re-coat over the +iodine full one fourth as long as first coating.” + +This exceedingly volatile compound is difficult to control from its +instability; it is but little used. The impressions successfully +produced by this mixture are very brilliant, and possess a pleasing +peculiarity. + +DRY SENSITIVES. + +Hydrate of Lime.—The operation by which water is combined with lime is +called slaking. Take a piece of quick lime, common lime used in mortar, +and immerse it in warm water for about fifteen seconds; then place it +in an iron or tin vessel. It will soon begin to swell, evolving a great +deal of heat and emitting steam, and soon falls into a fine powder, +hydrate of lime. This should be well stirred and allowed to cool, and +then bottled in order to prevent it from giving off the hydrate and +recovering the carbonic acid from the atmosphere. The last is +detrimental to its use with bromine, and is one cause of the complaint +that “it will not take bromine.” The hydrate of lime should, not be +dried over a heat, as has been supposed by many, for in that case the +hydrogen is expelled and it returns to a carbonate. It is advisable to +cool it in a damp place like a ground cellar. Much of the lime in our +market will not, except it be quite damp, combine with the bromine. +This is owing to impurities. Nothing is equal to oyster-shell lime, +which I use altogether. + +Bromide of Lime.—In preparing large quantities of this, we adopt the +following method: Fill a four-quart bottle about two-thirds full of +hydrate of lime; pour into this about one or two ounces of bromine; +then shake well, add more of the bromine, shake well and let it stand +for a few hours, adding sufficient bromine to give it a fine red color. +It is better when kept in the large bottles, as it forms a more perfect +combination: in other words it improves by age. + +Use.—Coat over the iodine to a rose red and then over this mixture to a +purple or slate; recoat over the first about one fourth as long as +first coating. + +Gurneys American Compound.—Of this compound there are two combinations, +one for use, when the temperature of the atmosphere is above 65 or 70 +deg., and the other at a lower temperature. The first is called No. 1, +the second No. 2. + +No. 1 is prepared by placing hydrate of lime in a bottle, say to three +quarts of the hydrate of lime, add one ounce of pulverized burnt alum, +and as much chloride of lime as can be put on a quarter of a dollar, +and from 15 to 30 grains of dry pulverized iodine, or enough to change +the color of the hydrate of lime, to the slightest possible tinge of +yellow. There had better be less than carry the color to a deeper +shade. The object of using the iodine is to form a compound with +bromine that is not so volatile as the bromine itself. No matter how +little iodine is combined with the bromine, the vapors possess their +relative proportion; hence, only enough iodine to prevent “flaring,” or +as it is often termed a “scum-coating,” is used. The iodine should be +thoroughly combined with the lime, which will take about one or two +days. Should add bromine the same as in bromide of lime, until the +compound assumes a light red color. + +No. 2 is prepared in the same manner as No. 1, except the addition of +the iodine, which is omitted. + +Use.—No. 1. Coat over the iodine to a bright yellow color, then over +the compound, No. 1, to red color, recoat over iodine, about one sixth +as long, as the time occupied in first coating. + +No. 2. Coat over iodine same as above, except recoat over the iodine +about one fourth to one half as long as first coating. + +Dry Quick, No. 1.—Bromide of Lime and Starch.—The following compound +forms an excellent accelerator, and is used by many. It is claimed for +this preparation, that it will hold the bromine longer than others +where starch is not employed. As regards this claim we do not think it +can be substantiated. Our experience in practice has led us to the +conclusion that there is no great difference as respects durability, +but there is some little difference as regards the tone of the +impressions produced by its use. + +To one quart of hydrate of lime add one quart of finely pulverized +starch. To this mixture add bromine, until it assumes a deep yellow or +pink color. + +Starch may be added to any of the dry mixtures. + +Use.—Coat over the iodine to a deep yellow, then over this quick to a +red color, recoat about one sixth of the time of first coating. + +I will here again remark, that the exact color of the coating is not +essentially provided a proper proportion is preserved. + +I have never seen it stated, though it be a fact worthy of note, that a +proportionate time for coating over the iodine and accelerator, will +not answer. For example: if a plate exposed to the vapor of iodine be +perfectly coated in sixteen seconds, and then exposed to an +accelerator, (not having iodine in its combination) receives its +coating in four seconds, it will be found that a proper proportionate +coating cannot be preserved by adopting, a proportion of time, but on +the contrary, the time will diminish; for exposure over the +accelerator, as in the above example, if it be desired to coat the +plate with twice as much iodine as in the above example, the time would +be, over iodine thirty-two seconds, and over the accelerator (to +possess a proper proportion) from six to seven seconds. Hence it is +that many inexperienced operators, when wishing to vary their usual +manner of coating, fail in producing a favorable result. They coat +calculating a proportion of time when they should not. + +Dry Quick, No. 2.—Bromide of Lime and Magnesia.—To one quart of hydrate +of lime add one quart of magnesia, and mix them well together; add +bromine same as in preparing bromide of lime; coat the same as over dry +quick No. 1. This combination produces very uniform results, and is +worked with much success by beginners. + +Chloro-Bromide of Lime.—To the bromide of lime add chloride of bromine +until the mixture becomes a pale yellow color, resembling sulphur. It +should be shook well, and enough of the chloride of bromine added to +bring the compound to a deep blood red color. + +Use.—Coat over the iodine to a pink color, and then over the above to a +red, or just changing the color. It should be remembered that +accelerators containing chlorine do not admit of a great change of +color of coating on the plate. + +Iodide of Starch.—This mixture can be employed for coating over in warm +weather, and prevent the flashing resulting at high temperatures. It +may be used the same as the iodide alone. + +To six ounces of finely pulverized starch, add one fourth ounce of dry +iodine. + +Use.—Same as the dry iodine alone. + +The same combination may be made with lime, magnesia and other +substances. + +Concentrated Solution of Iodine for First Coating.—It may appear +strange to some of our old operators that an aqueous solution of iodine +can be used for coating the plate and forming the iodide of silver. It +has long been a cry among most operators that it is impossible to +succeed when the iodine box contains dampness. Now this is a great +mistake, and we will here state that in all cases where dampness +appears upon a properly prepared Daguerreotype plate, it is the result +of a different temperature of the metal from the air which surrounds +it. Mr. Senter, of Auburn, was the first of our operators who used a +solution of iodine for coating the plate, and we several years since +saw his results, which would rival the production of any other +operator. A concentrated solution of iodine is prepared by putting into +a common bottle two thimblesful of hyposulphite of soda and a rather +larger quantity of iodine, so that there may be more than sufficient. +Add to it about 40 ounces of common water (heated to 60 or 70 degrees), +by little and little, moving, the bottle to warm it, for fear of +breaking. After shaking it a short time, the water is rapidly and +strongly colored. The solution should be poured into a bottle with a +ground stopper, and when cool used for iodizing. + +A solution of sufficient strength can be made by moistening or just +covering the iodine with water. + +Chloride of Iodine as an Accelerator.—This is probably one of the best +accelerators that can be used for coating the plate for taking views; +it works too slow, however, to meet the wants of the operating room, +yet its use was formerly, for a long time, adhered to by some of our +best professors. In producing views with this, we are successful in +obtaining well-developed impressions, with a depth of tone and richness +of appearance not to be met with in the productions of any other +substances. I give its use as furnished me by an old and experienced +operator, and published in Humphrey’s Journal, vol. i. p. 180: + +“As the process of using chloride of iodine may be of interest to some +of our subscribers, I take pleasure in giving the following +manipulation. To one ounce of chloride of iodine add two ounces of +water; place this mixture in a coating-box, the same as quick stuff; +coat the plate with dry iodine to a light yellow, or lemon color; then +bring the coating to a deep pink over the chloride. The plate must be +recoated over the dry iodine.” + +This combination has been very successfully used in one of our most +extensive establishments in this city, and the superiority of the +pictures produced by it was considered as an equivalent for the +additional time required to bring out the impressions. + +Chlorine as an Accelerator.—I shall here refer to but a single +experiment in which I employed chlorine gas for coating the plate. I +was provided with a retort, the neck of which was fitted to the jar of +my coating-box, through a hole drilled for its reception. This was +fitted perfectly tight in my coating-box. I placed some pure undiluted +bromine water and the agents necessary for producing chlorine gas (in +small quantity) in the retort. The result was that my first experiment +produced an impression completely solarized in all its parts by an +exposure of four seconds of time, which would have required an exposure +of twenty seconds to produce a perfectly developed impression by the +usual process. + +Another trial immediately produced one of the finest toned impressions +I ever saw, perfectly developed in one second of time. + +My next two or three experiments proved total failures. I was unable to +produce even a sign of an impression. By accident my retort was broken, +and not being in a locality convenient to obtain another, my +experiments were necessarily suspended. + +My attention was not called to this subject again for several years, +when I noticed an account of some similar experiments by F. A. P. +Barnard and Dr. W. H. Harrington, the latter of whom is now of the firm +of Dobyns & Harrington, of New Orleans. + +From reading this article, I found my own difficulties explained. Too +much of the chlorine gas was present in my coating jar. I would like to +see some of our enterprising operators investigate this combination. + +It is a singular fact, that the vapors of bromine and chlorine +combining upon the iodide of silver, produce a more sensitive coating +than when the two are combined in solution, as in chloride of bromine +solution. Those having Humphrey’s Journal at hand, can refer to vol. i. +p. 142. + +To use Bromine Water or other Accelerators in Hot Weather.—An excellent +plan for using bromine water is as follows: + +Fill a two-ounce bottle quarter full of it, and then fill the bottle +with fine sand, which serves to preserve a low temperature; then place +the bottle in a porous cup, same as used in the battery; fill this also +with sand, and close the end with plaster of Paris. Place this in a +coating-box, and it will be found to act with great uniformity and be +quite permanent. + +Bromide of Lime, another accelerator, can be used in the same manner, +except it is, only necessary, when a solid sensitive is used, to mix it +with the sand without placing it in a bottle. This method is employed +with great success by a few, who have regarded it as a secret worth +keeping. + +A Combination, requiring the Use of only One Coating-box.—It is often +wondered by beginners, why some solution requiring only one coating +cannot be employed. This can be done, but the results are not so +satisfactory as when two or more are employed. Such an accelerator may +be produced by adding alcoholic solution of iodine to a solution of +chlorate of potash, until the latter will take up no more of the +former, and to each ounce, by measure of this solution, ten drops of a +saturated solution of bromide in water are added. The solution of +chlorate of potash is made by diluting, one part of a saturated +solution of the salt with ten parts of water. The use of the chlorate +is simply as a solvent of iodine. + +Fats as Accelerators.—The use of fats, oils, or greasy substances, has +been one of the most emphatic prohibitions about the Daguerreotype +plate. Yet it has been proved that its presence in a small quantity +upon the silver surface has the effect of reducing the time of exposure +in the camera from two-thirds to three-fourths. An application may be +made as follows: Pour sweet oil, or rub beef or mutton fat, on a common +buff, which is free from all polishing powders. With this, buff a +well-cleaned plate, and it will leave a scum, which should be mostly +removed by using another buff, which should be clean. Coat the plate in +the usual manner, and the result will be a great reduction in the time +of exposure in the camera. The impression produced upon a plate so +prepared presents, when coming from the vapor of mercury, a grey, +scummy appearance, which, on the application of heat in gilding, does +not improve; hence its use is not generally adopted. + +We have instituted some investigations upon this subject, and in the +present volume, we shall not refer to it further. Those wishing to +learn more fully the effect of light upon organic substances will find +Robert Hunt’s “Researches on Light” an invaluable work. + + + + +CHAPTER IV. + +LIGHT AND OPTICS. + + +Light—Optics—Solar Spectrum—Decomposition of Light—Light, Heat, and +Actinism—Blue Paper and Color for the Walls of the Operating +Room—Proportions of Light, Heat, and Actinism composing a +Sunbeam—Refraction—Reflection—Lenses—Copying Spherical +Aberration—Chromatic Aberration. + +It is advisable that persons engaging in the Daguerreotype art should +have at least a little knowledge of the general principles of light and +optics. It is not the author’s design here to give a full treatise on +these subjects, but he only briefly refers to the matter, giving a few +facts. + +It has been well observed by an able writer, that it is impossible to +trace the path of a sunbeam through our atmosphere without feeling a +desire to know its nature, by what power it traverses the immensity of +space, and the various modifications it undergoes at the surfaces and +interior of terrestrial substances. + +Light is white and colorless, as long as it does not come in contact +with matter. When in apposition with any body, it suffers variable +degrees of decomposition, resulting in color, as by reflection, +dispersion, refraction, and unequal absorption. + +To Sir I. Newton the world is indebted for proving the compound nature +of a ray of white light emitted from the sun. The object of this work +is not to engage in an extended theory upon the subject of light, but +to recur only to some points of more particular interest to the +photographic operator. + +The decomposition of a beam of light can be noticed by exposing it to a +prism. If, in a dark room, a beam of light be admitted through a small +hole in a shutter, it will form a white round spot upon the place where +it falls. If a triangular prism of glass be placed on the inside of the +dark room, so that the beam of light falls upon it, it no longer has +the same direction, nor does it form a round spot, but an oblong +painted image of seven colors—red, orange, yellow, green, blue, indigo, +and violet. This is called the solar spectrum, and will be readily +understood by reference to the accompanying diagram, Fig. 1. + +{133} + +To those who are unacquainted with the theory of light (and for their +benefit this chapter is given), it may be a matter of wonder how a beam +of light can be divided. + +[Illustration: Fig. 1] + +This can be understood when I say, that white light is a bundle of +colored rays united together, and when so incorporated, they are +colorless; but in passing through the prism the bond of union is +severed, and the colored rays come out singly and separately, because +each ray has a certain amount of refracting (bending) power, peculiar +to itself. These rays always hold the same relation to each other, as +may be seen by comparing every spectrum or rainbow; there is never any +confusion or misplacement. + +There are various other means of decomposing {134} white light besides +the prism, of which one of the principal and most interesting to the +Daguerreotypist is by reflection from colored bodies. If a beam of +white light falls upon a white surface, it is reflected without change; +but if it falls upon a red surface, only the red ray is reflected: so +also with yellow and other colors. The ray which is reflected +corresponds with the color of the object. It is this reflected +decomposed light which prevents the beautifully-colored image we see +upon the ground glass in our cameras. + +[Illustration: Fig. 2] + +A sunbeam may be capable of three divisions—LIGHT, HEAT, and ACTINISM; +the last causes all the chemical changes, and is the acting power upon +surfaces prepared to receive the photographic image. The accompanying +illustration, Fig. 2, will readily bring to the mind of the reader the +relation of these one to another, and their intensities in the +different parts of a decomposed sunbeam. + +The various points of the solar spectrum are represented in the order +in which they occur between A, and B, this exhibits the limits of the +Newtonian spectrum, corresponding with Fig. 1. Sir John Herschel and +Seebeck have shown that there exists, beyond the violet, a faint violet +light, or rather a lavender to b, to which gradually becomes colorless; +similarly, red light exists beyond the assigned limits of the red ray +to a. The greatest amount of actinic power is shown at E opposite the +violet; hence this color “exerts” the greatest amount of influence in +the formation of the photographic image. + +(Blue paper and blue color have been somewhat extensively used by our +Daguerreotype operators in their operating rooms and skylights, in +order to facilitate the operation in the camera. I fancy, however, that +this plan cannot be productive of as much good as thought by some, from +the fact, that the light falling upon the subject, and then reflected +into the camera, is, coming through colorless glass, not affected by +such rays as may be reflected from the walls of the operating room; and +even if it were so, I conceive that it would be injurious, by +destroying the harmony of shadows which might otherwise occur.) The +greatest amount of white light is at C; the yellow contains less of the +chemical power than any other portion of the solar spectrum. It has +been found that the most intense heat is at the extreme red, b. + +Artificial lights differ in their color; the white light of burning +charcoal, which is the principal light from candles, oil and gas, +contains three rays—red, yellow, and blue. The dazzling light emitted +from lime intensely heated, known as the Drummond light, gives the +colors of the prism almost as bright as the solar spectrum. + +If we expose a prepared Daguerreotype plate or sensitive paper to the +solar spectrum, it will be observed that the luminous power (the +yellow) occupies but a small space compared with the influence of heat +and chemical power. R. Hunt, in his Researches on Light, has presented +the following remarks upon the accompanying illustration: + +[Illustration: Fig. 3] + +“If the linear measure, or the diameter of a circle which shall include +the luminous rays, is 25, that of the calorific spectrum will be 42.10, +and of the chemical spectrum 55.10. Such a series of circles may well +be used to represent a beam from the sun, which may be regarded as an +atom of Light, surrounded with an invisible atmosphere of Heat, and +another still more extended, which possesses the remarkable property of +producing chemical and molecular change. + +A ray of light, in passing obliquely through any medium of uniform +density, does not change its course; but if it should pass into a +denser body, it would turn from a straight line, pursue a less oblique +direction, and in a line nearer to a perpendicular to the surface of +that body. Water exerts a stronger refracting power than air; and if a +ray of light fall upon a body of this fluid its course is changed, as +may be seen by reference to Fig. 4. + +[Illustration: Fig. 4] + +It is observed that it proceeds in a less oblique direction (towards +the dotted line), and, on passing on through, leaves the liquid, +proceeding in a line parallel to that at which it entered. It should be +observed that at the surface of bodies the refractive power is exerted, +and that the light proceeds in a straight line until leaving the body. +The refraction is more or less, and in all cases in proportion as the +rays fall more or less obliquely on the refracting surface. It is this +law of optics which has given rise to the lenses in our camera tubes, +by which means we are enabled to secure a well-delineated +representation of any object we choose to picture. + +When a ray of light passes from one medium to another, and through that +into the first again, if the two refractions be equal, and in opposite +directions, no sensible effect will be produced. + +The reader may readily comprehend the phenomena of refraction, by means +of light passing through lenses of different curves, by reference to +the following diagrams:— + +[Illustration: Fig. 5, 6, 7] + +Fig 5 represents a double-convex lens, Fig. 6 a double-concave, and +Fig. 7 a concavo-convex or meniscus. By these it is seen that a +double-convex lens tends to condense the rays of light to a focus, a +double-concave to scatter them, and a concavo-convex combines both +powers. + +If parallel rays of light fall upon a double-convex lens, D D, Fig. 8, +they will be refracted (excepting such as pass directly through the +centre) to a point termed the principal focus. + +[Illustration: Fig. 8] + +The lines A B C represent parallel rays which pass through the lens, D +D, and meet at F; this point being the principal focus, its distance +from the lens is called the focal length. Those rays of light which are +traversing a parallel course, when they enter the lens are brought to a +focus nearer the lens than others. Hence the difficulty the operator +sometimes experiences by not being able to “obtain a focus,” when he +wishes to secure a picture of some very distant objects; he does not +get his ground glass near enough to the lenses. Again, the rays from an +object near by may be termed diverging rays. This will be better +comprehended by reference to Fig. 9, where it will be seen that the +dotted lines, representing parallel rays, meet nearer the lenses than +those from the point A. The closer the object is to the lenses, the +greater will be the divergence. This rule is applicable to copying. Did +we wish to copy a 1/6 size Daguerreotype on a 1/16 size plate, we +should place it in such a position to the lenses at A that the focus +would be at F, where the image would be represented at about the proper +size. Now, if we should wish to copy the 1/6 size picture, and produce +another of exactly the same dimensions, we have only to bring it nearer +to the lenses, so that the lens D E shall be equi-distant from the +picture and the focus, i. e. from A to B. The reason of this is, that +the distance of the picture from the lens, in the last copy, is less +than the other, and the divergence has increased, throwing, the focus +further from the lens.” + +[Illustration: Fig. 9] + +These remarks have been introduced here as being important for those +who may not understand the principles of enlarging or reducing pictures +in copying. + +I would remark that the points F and A, in Fig. 9, are termed +“conjugate foci.” + +If we hold a double-convex lens opposite any object, we find that an +inverted image of that object will be formed on a paper held behind it. +To illustrate this more clearly, I will refer to the following woodcut: + +[Illustration: Fig. 10] + +“If A B C is an object placed before a convex lens, L L, every point of +it will send forth rays in all directions; but, for the sake of +simplicity, suppose only three points to give out rays, one at the top, +one at the middle, and one at the bottom; the whole of the rays then +that proceed from the point A, and fall on the lens L L, will be +refracted and form an image somewhere on the line A G E, which is drawn +direct through the centre of the lens; consequently the focus E, +produced by the convergence of the rays proceding from A, must form an +image of A, only in a different relative position; the middle point of +C being in a direct line with the axis of the lens, will have its image +formed on the axis F, and the rays proceeding from the point B will +form an image at D; so that by imagining luminous objects to be made up +of all infinite number of radiating points and the rays from each +individual point, although falling on the whole surface of the lens, to +converge again and form a focus or representation of that point from +which the rays first emerged, it will be very easy to comprehend how +images are formed, and the cause of those images being reversed. + +“It must also be evident, that in the two triangles A G B and D G E, +that E D, the length of the image, must be to A B, the length of the +object, as G D, the distance of the image, is to G B, the distance of +the object from the lens. + +It will be observed that in the last cut the image produced by the lens +is curved. Now, it would be impossible to produce a well-defined image +from the centre to the edge upon a plain surface; the outer edges would +be misty, indistinct, or crayon-like. The centre of the image might be +represented clear and sharp on the ground glass, yet this would be far +from the case in regard to the outer portions. This is called spherical +aberration, and to it is due the want of distinctness which is +frequently noticed around the edges of pictures taken in the camera. To +secure a camera with a flat, sharp, field, should be the object of +every operator; and, in a measure, this constitutes the great +difference in cameras manufactured in this country. + +Spherical aberration is overcome by proper care in the formation of the +lens: “It can be shown upon mathematical data that a lens similar to +that given in the following diagram—one surface of which is a section +of an ellipse, and the other of a circle struck from the furthest of +the two foci of that ellipse—produces no aberration. + +“At the earliest period of the employment of the camera obscura, a +double-convex lens was used to produce the image; but this form was +soon abandoned, on account of the spherical aberration so caused. +Lenses for the photographic camera are now always ground of a +concavo-convex form, or meniscus, which corresponds more nearly to the +accompanying diagram.” + +[Illustration: Fig. 11] + +Chromatic Aberration is another difficulty that opticians have to +contend with in the manufacturing of lenses. It will be remembered, +that in a former page (133) a beam of light is decomposed by passing +through a glass prism giving seven distinct colors—red, orange, yellow, +green, blue, indigo and violet. + +Now, as has been said before, the dissimilar rays having an unequal +degree of refrangibility, it will be impossible to obtain a focus by +the light passing through a double-convex lens without its being +fringed with color. Its effect will be readily understood by reference +to the accompanying cut. + +[Illustration: Fig. 8] + +If L L be a double convex-lens, and R R R parallel rays of white light, +composed of the seven colored rays, each having a different index of +refraction, they cannot be refracted to one and the same point; the red +rays, being the least refrangible, will be bent to r, and the violet +rays, being the most refrangible, to v: the distance v r constitutes +the chromatic aberration, and the circle, of which the diameter is a l, +the place or point of mean refraction, and is called the circle of +least aberration. If the rays of the sun are refracted by means of a +lens, and the image received on a screen placed between C and o, so as +to cut the cone L a l L, a luminous circle will be formed on the paper, +only surrounded by a red border, because it is produced by a section of +the cone L a l L, of which the external rays L a L l, are red; if the +screen be moved to the other side of o, the luminous circle will be +bordered with violet, because it will be a section of the cone M a M l, +of which the exterior rays are violet. To avoid the influence of +spherical aberration, and to render the phenomena of coloration more +evident, let an opaque disc be placed over the central portion of the +lens, so as to allow the rays only to pass which are at the edge of the +glass; a violet image of the sun will then be seen at v, red at r, and, +finally, images of all the colors of the spectrum in the intermediate +space; consequently, the general image will not only be confused, but +clothed with prismatic colors.” + +To overcome the difficulty arising from the chromatic aberration, the +optician has only to employ a combination of lenses of opposite focal +length, and cut from glass possessing different refrangible powers, so +that the rays of light passing through the one are strongly refracted, +and in the other are bent asunder again, reproducing white light. + +To the photographer one of the most important features, requiring his +particular attention, is, that he be provided with a good lens. By the +remarks given in the preceding pages, he will be enabled, in a measure, +to judge of some of the difficulties to which he is occasionally +subjected. We have in this country but two or three individuals who are +giving their attention to the manufacture of lenses, and their +construction is such, that they are quite free from the spherical or +chromatic aberration. + + + + +CHAPTER V. + + +To make Plates for the Daguerreotype—Determining the Time of Exposure +in the Camera—Instantaneous Process for Producing +Daguerreotype—Galvanizing the Daguerreotype Plate—Silvering +Solution—Daguerreotype without Mercury—Management of Chemicals—Hints +and Cautions—Electrotyping—Crayon Daguerreotypes—Illuminated +Daguerreotypes—Natural Colors in Heliography—Multiplying Daguerreotypes +on one Plate—Deposit in Gilding—Practical Hints on the Daguerreotype. + +TO MAKE PLATES FOR THE DAGUERREOTYPE. + +I do not give the method employed by our regular plate manufacturers; +this is not important, as the operator could not possibly profit by it +from the fact of the great expense of manufacturing. The following will +be found practical: + +Procure a well planished copper plate of the required size, and well +polish it, first with pumice stone and water, then with snake stone, +jewelers’ rouge. Plates can be purchased in a high state of preparation +from the engravers. Having prepared the copper-plate, well rub it with +salt and water, and then with the silvering powder. No kind answers +better than that used by clock-makers to silver their dial-plates. It +is composed of one part of well washed chloride of silver, five parts +of cream of tartar, and four parts of table salt. This powder must be +kept in a dark vessel, and in a dry place. For a plate six inches by +five, as much of this composition as can be taken up on a shilling is +sufficient. It is to be laid in the centre of the copper, and the +figures being wetted, to be quickly rubbed over every part of the +plate, adding occasionally a little damp salt. The copper being covered +with the silvering is to be speedily well washed in water, in which a +little soda is dissolved, and as soon as the surface is of a fine +silvery whiteness, it is to be dried with a very clean warm cloth. In +this state the plates may be kept for use. The first process is to +expose the plate to the heat of a spirit flame, until the silvered +surface becomes of a well-defined golden-yellow color; then, when the +plate is cold, take a piece of cotton, dipped in very dilute nitric +acid, and rub lightly over it until the white hue is restored, and dry +it with very soft clean cloths. A weak solution of the hydriodate of +potash, in which a small portion of iodine is dissolved, is now passed +over the plate with a wide camel’s hair brush. The silver is thus +converted, over its surface, into an ioduret of silver; and in this +state it is exposed to light, which blackens it. When dry, it is to be +again polished, either with dilute acid or a solution of carbonate of +soda, and afterwards with dry cotton, and the smallest possible portion +of prepared chalk: by this means a surface of the highest polish is +produced. The rationale of this process is, in the first place, the +heat applied dries off any adhering acid, and effects more perfect +union between the copper and silver, so as to enable it to bear the +subsequent processes. The first yellow surface appears to be an oxide +of silver with, possibly, a minute quantity of copper in combination, +which being removed leaves a surface chemically pure. + +Another Method.—The best and simplest mode with which we are acquainted +is to divide an earthenware vessel with a diaphragm: one side should be +filled with a very dilute solution of sulphuric acid, and the other +with either a solution of ferroprussiate of potash, or muriate of soda, +saturated with chloride of silver. The copper plate, varnished on one +side, is united, by means of a copper wire, with a plate of zinc. The +zinc plate being immersed in the acid, and the copper in the salt, a +weak electric current is generated, which precipitates the silver in a +very uniform manner over the entire surface. + +Another Method.—A piece of brass or of polished copper, brass is +preferred, is perfectly planished and its surface made perfectly clean. +A solution of nitrate of silver, so weak that the silver is +precipitated slowly, and a brownish color, on the brass, is laid +uniformly over it, “at least three times,” with a camel’s hair pencil. +After each application of the nitrate, the plate should be rubbed +gently in one direction, with moistened bitartrate of potassa, applied +with buff. This coat of silver receives a fine polish from peroxide of +iron and buff. Proofs are said to have been taken on it, comparable +with those obtained on French plates. + +M. SOLIEL’S PROCESS FOR DETERMINING THE TIME OF EXPOSURE IN THE CAMERA. + +M. Soliel has proposed the use of the chloride of silver to determine +the time required to produce a good impression on the iodated plate in +the camera. His method is to fix at the bottom of a tube, blackened +within, a piece of card, on which chloride of silver, mixed with gum or +dextrine, is spread. The tube thus disposed is turned from the side of +the object of which we wish to take the image, and the time that the +chloride of silver takes to become of a greyish slate color will be the +time required for the light of the camera to produce a good effect on +the iodated silver. + +INSTANTANEOUS PROCESS FOR PROCURING DAGUERREOTYPES. + +The following method of producing Daguerreotypes has by some been named +as above. Most experienced operators have been long acquainted with the +effect of the vapor of ammonia upon the chemically coated plate. I will +here insert Mr. W. H. Hewett’s plan of proceeding. This gentleman, in +referring to it (published in 1845), says: + +“This improvement consists in using the vapor of ammonia, as an object +to accelerate the action of light upon the plate. The effect is +produced upon a simple iodized plate, but still more upon a plate +prepared in the ordinary way, with both iodine and bromine. By this +means, the author obtained impressions instantaneously in the sunshine, +and in five to ten seconds in a moderate light; and he hopes to be able +to take moving objects. It can be applied by exposing the prepared +plate over a surface of water, to which a few drops of ammonia have +been added (sufficient to make it smell of ammonia); or the vapor can +be introduced into the camera during the action. In fact, the presence +of ammonia, in the operating-room, appears to have a good effect, as it +also neutralizes the vapors of iodine and bromine that may be floating +about, and which are so detrimental to the influences of light upon the +plate.” + +GALVANIZING THE DAGUERREOTYPE PLATE. + +In consideration of the importance of galvanized plates, I shall +endeavor to give as plain and concise a manner of manipulation as +possible. For some time it was a question among the operators +generally, as to the beneficial result of electrotyping, the +Daguerreotype plate, but for a few years past our first operators have +found it a fact, that a well electro-silvered surface is the best for +producing a portrait by the Daguerreotype. + +From my own experiments, I have found that a plate, by being +galvanized, can be rendered more sensitive to the operation of the +light in proportion of one to five, viz.: if a plate as furnished by +the market, be cleaned, polished, coated and exposed in the camera, if +the required time to freely develop an impression be ten seconds, a +similar plate prepared in like manner and galvanized, will produce an +equally well-defined image in eight seconds. In connection with this +subject, there is one fact worthy of notice; a plate with a very heavy +coating of pure silver, will not produce an equally developed image, as +a plate with a thinner coating, hence the thin coating, providing it +entirely covers the surface, is the best, and is the one most to be +desired. The experiment is plain and simple. Let the slate receive a +heavy or thick coating by the electrotype, then polish, coat, expose in +the usual manner, and the result will be a flat, ashy, indistinct +impression; when, on the other hand, the thin coating will produce a +bright, clear and distinct image, with all the details delineated. + +The style of battery best for the purpose has been, and now is, a +question of dispute among operators; some preferring the Daniell +battery to Smee’s. Some claim the superiority of the first from its +uniformity of action; others, of the latter, for its strength. I +consider either good, and for the inexperienced would prefer the +Daniell. This is more simple in its construction, while it has +certainty in action. The more skillful electrotyper would prefer +Smee’s, and this is the one most generally in use. I would remark that +the plan of galvanizing plates should be followed by every operator, +and when once thoroughly tested, no one will abandon it. + +SILVERING SOLUTION. + +To any desired quantity of chloride of silver in water add, little by +little, cyanide of potassium, shaking well at each addition, until all +the cyanide is dissolved. Continue this operation, and add the cyanide, +until all the precipitate is taken up and held in solution. + +This solution is now ready for the plate-cup. Enough water may be added +to cover any sized plate when held perpendicular in the cup. The +strength of the solution may be kept up by occasionally adding the +chloride of silver and cyanide of potassium. There should alway be a +very little excess of the cyanide. + +The plate should be well cleaned and buffed, and the solution well +stirred before it is immersed. Care should be observed to keep the +solution clean, and allow no particle of dust to come in contact with +the surface of the plate. The plate is now to be attached to the pole +of the battery. + +After remaining a short time, it assumes a blue color; take it out, +rinse freely with pure water, then dry with a spirit lamp, and it is +ready for buffing. Buff and coat in the usual manner. Some operators +are in the practice of immersing the plate in the solution and buffing +twice. This additional silvering is no improvement wherever there has +been a proper first coating. + +Sometimes the operator is troubled with streaks or scum on the plate. +This may arise from three causes, all of which experience must teach +the experimenter to avoid; first, too great an excess of cyanide in the +solution; second, a lack of silver; third, the current too strong. +Another annoyance arises from the solution being dirty and the dirt +collecting on the surface. When this is the case, the dirt is sure to +come in contact with the surface of the plate as it is plunged into the +solution, and the result is a scum that it is difficult to dispose of. +This can be prevented only by frequent filtering. One thing should +always be borne in mind in electrotyping Daguerreotype plates—that in +order to secure a perfectly coated surface, the plate should be +perfectly cleaned. In this point, many who have tried the electrotype +process have failed, attributing their ill success to other than the +proper cause. + +DAGUERREOTYPES WITHOUT MERCURY. + +The following process possesses some interest, and is worthy a trial +from operators. M. Natterer, of Vienna, discovered a process for +obtaining proofs on iodized plates with the chloride of sulphur, +without the use of mercury. A plate of silver is iodized in the usual +manner, and then placed on the top of a vessel six or eight inches +high, having at the bottom, in a small cup, a few drops of chloride of +sulphur; it should remain exposed to the action of the vapor until the +sombre yellow color is changed to a red, after which it is brought to a +focus in the camera, where it is exposed to the light in the camera, +for about the time necessary to produce an ordinary daguerreotype. The +plate is then taken out and examined in the camera by the light of a +candle. It often occurs that no trace of the image is as yet +perceptible, but if the plate is heated by placing over a spirit lamp +the unprepared side, or if left for some time in the dark, or, lastly, +if exposed only a few seconds to a weak, dimmed light, the positive +picture then appears with all its shades. Of these three modes of +bringing out the image, the second is superior to the others. + +MANAGEMENT OF CHEMICALS. + +It is necessary, first of all, to know that you have a chemical which +is capable of producing good results when in skillful hands. For this +reason it is best to prepare your own quick, after some formula which +is known to be good. Those quick-stuffs which contain chloride of +iodine are noted for their depth of tone while they probably operate +with less uniformity than those which are destitute of it. For +operating under ordinary circumstances, especially with an inferior +light, probably no accelerator is more quick and sure than Wolcott’s. +It also produces a very fine, white pleasing picture, though lacking +that depth of impression so much to be desired. The dry quick operates +with surety, and its use is simple and easy, producing an impression +much like Wolcott’s. For those having a good and permanent light, +however, we would recommend a chemical giving more body to the +impression. + +There is a class of accelerators called sensitives, claiming to work in +from three to ten seconds, which, however, will be found very little, +if any, more sensitive than this. We frequently work it with the +ordinary coating in twelve and fifteen seconds. The manner in which the +sensitives are worked is by coating very light. In this way, a flat, +shallow picture is obtained in a few seconds; and the same can be done +with any of the more volatile quicks. + +It is a fact not generally known, that a plate coated in a light +chemical room is more sensitive than when coated in darkness. By +admitting a free, uniform light, and exposing the plate to it a few +seconds after coating, then timing short in the camera, a very light, +clear impression is obtained. The time in the camera is reduced in +proportion to the previous action of light. The shades, of course, are +destroyed, and the tone injured; still, for taking children, we have +succeeded better by this method than by the use of “sensitives.” The +discovery of this principle was accidental, while operating where the +direct ray s of the sun, entering the window just before sunset, fell +on the curtain of our dark room, rendering it very light within. + +The selection of iodine is not unimportant. Reject, at once, that which +has anything like a dull, black, greasy appearance; and select that +which is in beautiful large crystalline scales, of a purple color, and +brilliant steel lustre. + +Solarization, and general blueness of all the light parts of the +picture, were formerly great obstacles to success, though now scarcely +thought of by first-class artists. Beginners in the art, however, are +still apt to meet with this difficulty. It is occasioned by dampness in +the iodine box, which causes the plate to become coated with a +hydro-iodide of silver, instead of the iodide. The remedy is in drying +your iodine. If in summer, you can open your box and set it in sunshine +a few minutes; or if in winter, set it under a stove a short time. The +true method, however, is to dry it by means of the chloride of calcium. +It has such a remarkable affinity for water, that a small fragment +placed in the open air, even in the dryest weather, soon becomes +dissolved. + +Take one or two ounces of this chemical, heat it in the drying bath, or +in a hot stove, to perfect dryness; place it in a small glass toy dish, +or large watch crystal, and set it in the centre of your iodine box. +Take this out and heat to dryness every morning. Adopt this process, +and with your mercury at a high temperature, you will never be troubled +with blue pictures. + +Young operators are apt to impute all want of success in operating to +their chemicals, even though the cause is quite as likely to be +elsewhere. Failure is quite likely to occur from dampness in the buffs, +or in the polish; it is therefore necessary to be constantly on the +guard in this quarter. With a view to this, always scrape your buffs +with a dull knife, or with one blade of your shears, the first thing in +the morning, and after brushing them thoroughly, dry them, either in +the sun, by a stove, or in the buff-dryer. It is equally important that +the polish and the brush should be kept dry. + +Want of success may arise from vapors of iodine or bromine in the +camera box, mercury bath, or even in the buffs. It is incredible how +small a quantity of these vapors will affect the effect of light when +coming in contact with the plate, after or during the exposure in the +camera. It is therefore necessary to be cautious not to mix chemicals, +nor open your boxes or bottles in your room, but take them out to do +it. Never hurry the operation through from lack of confidence in the +result. The fact of anything being out of order, forms no excuse for +slighting the process. If unsuccessful, do not pursue the same course +every trial, but vary with a view to detect the cause of the +difficulty. + +In case of a long series of failures, institute a regular course of +investigation, after this manner, commencing where the trouble is most +likely to occur: + +1. Are the plates well cleaned? + +2. Is the iodine dry? If the impressions come out blue, you may rest +assured it is not. Take out the iodine, wipe and dry the box, and dry +the calcium. + +3. Is the quick battery of the right strength? If dry, it must change +the plate in from six to fifteen seconds. If any of the chloride of +iodine class, it may vary from five seconds to a minute. Begin by +coating light, and increase on each trial, observing the effect. If the +light side of the picture seems loth to come out, and shows no contrast +with the dark side, it is to be inferred that your battery is too +strong, and must be reduced with water or set out in the open air for a +few minutes, with the lid off. If working an old battery, never renew +very strong, or it will work dark and heavy. A battery, to work well, +should be gradually losing strength, but never gaining. An old battery, +however, may be quickened up and made to work well for some time, by +adding five of six drops of sulphuric acid, repeating the quantity as +often as necessary, providing always that acid be not used in +manufacturing the quick. + +4. Have the plates lost their sensitiveness by being many times exposed +to mercury? Clean and burn them; but if French plates, burn light, or +you spoil them. + +5. Are the buff s dry and clean? Examine the plate critically after +buffing to detect any appearance of scum or film on the surface. If so, +the longer you buff the more it shows. Scrape and dry the buffs +thoroughly. + +6. Is the mercury free from scum and dirt? If not, filter. Is it also +far enough from the coating boxes? Should be at least three feet, and +kept covered. + +7. Is the mercury sufficiently heated? This is important. Long +exposure, however, will answer the same purpose. + +8. Are your lenses clean, and in proper place? + +9. Are the tablets in focus with the ground-glass? If you can attribute +the failure to none of these, mix a new box of some other kind of +quick, say the dry, for instance. If you fail in the same manner here, +take time, wash your buffs, overhaul all the chemicals, and start anew. +Do not be discouraged. + +There is no day so dark but that the sun will shine again. We will +close with this brief summary of advice: + +Clean your plates. Keep everything dry. Keep the mercury hot. Follow +these instructions carefully, and you must succeed. + +HINTS AND CAUTIONS. + +First of all, cleanliness should be observed. When there is dust or +dirt about your room, particularly about the work-bench, failures will +be frequent; for the smallest particles of rotten-stone, when allowed +to come in contact with the buffs, will produce scratches on the +surface of the plate, which very much injures the operation, and often +causes failures. + +Dust flying about the room is injurious, if allowed to fall on the +plate, either before or after it has been coated, as it causes black +spots which cannot be removed. + +The polished plate should not be allowed to come in contact with a +strong current of air, for it tends to oxidize the surface. Breathing +on the surface should also be avoided, for the same reason. + +The plate should, in all cases, be buffed immediately before using, and +not allowed to stand any length of time. It should be held with the +polished face downward. + +It is always best that the plate should be of the same temperature of +the atmosphere in the room. + +Keep the camera and mercury-bath perfectly free from the vapors of +iodine and bromine; for the presence of the slightest degree of either +of the above will injure the impression in no small degree. As a +preventive, let the camera be exposed to the sun or fire for a few +minutes in the morning. + +Filter your mercury often, to keep the surface free from film and dust. + +The hyposulphite solution should be filtered through sponge every time +it is used. + +The direct rays of light must not enter the camera in conjunction with +those reflected from the object; or the picture will be veiled, and the +color of the plate changed to a thick green. + +If the plate be iodized only to a light-yellow, the result might be of +a bluish or grey tinge: and this is generally the case, when the quick +is new and strong, and there is an excess of it on the plate, and yet +not enough to form the bromide iodide of silver; in which case it would +wholly spoil the impression. + +Your iodine will be found to operate more successfully, when the time +required for coating the plate does not fall short of fifteen seconds, +or exceed one minute. + +Too quick coating can be avoided by using less iodine in your box. In +the summer months, when the weather is 80 deg. and over, one quarter of +an ounce, or even less, will work to advantage. + +ELECTROTYPING. + +I am indebted to Mr. J. H. Fitzgibbons for the following process, which +he employed in producing the excellent specimens he exhibited at the +Crystal Palace: + +“I shall endeavor to lay down in as comprehensive a manner as possible +the method by which I have been enabled to produce the most +satisfactory results. I use a Smee’s battery (another kind will do). +After filling the cell, of common size, nearly full with water; add +about quarter of an ounce of sulphuric acid. Mix this well, and let it +stand for about three hours, or until the action of the battery becomes +weak, when it is in order to work with a very uniform action. Put one +pound of sulphate of copper in one quart of water; stir it until the +sulphate of copper is all dissolved, and then add one half ounce of +sulphuric acid and a quarter of an ounce of nitric acid. This solution, +well mixed, should be filtered, and it is ready for use. It is very +important that the solution should be kept clean, clear, and free from +all foreign substance. The above quantity of this solution will be +found sufficient for electrotyping a dozen of the sixth-size plates. +When it is required to be strengthened, it is only necessary to add a +little of the sulphate of copper. + +“With the battery prepared as above, and the solution of sulphate of +copper in a vessel of proper dimensions to receive your plate, connect +the galvanic current, and immerse the impressioned plate, letting it +remain until a thin film of copper has been formed, then the battery +can be strengthened, and the impression will be of sufficient thickness +to be removed in from eight to twelve hours. An old Daguerreotype plate +attached to the opposite pole of the battery (copper side towards the +face of the plate to be electrotyped), will answer the same purpose as +the silver-plate. + +“The great difficulty in taking an electrotype impression, and +preserving the original, has been attributed to the battery being too +powerful. I am led to believe from practice that the principal +difficulty has been in the Daguerreotype plate itself, for if we use an +impression that has been taken but a few days, and taken in the usual +way, we will find it difficult to succeed without spoiling both the +copy and original, and so also with an old impression. + +“I have found the most certain method to be as follows:—Coat the +Daguerreotype plate as usual, except use less of the accelerators, the +proportion of iodine coating being greater, of course the time of +exposure in the camera will be lengthened. Mercurialize it at about a +temperature requiring to develop the image, from six to eight minutes, +at least. Gilding the Daguerreotype has much to do towards producing a +good electrotype copy. This should be done by applying a little heat, +and gilding very slowly, giving a coating of gold with the greatest +possible uniformity. By this method, I have been enabled to produce any +number of proofs. I have produced a dozen from one impression, and it +remains as perfect as when first taken. + +“By a little judgment and care the operator will be enabled to produce +the electrotype copy of the Daguerreotype plate without any difficulty. +The electrotype copy should be immediately put under a glass and sealed +in the same manner as the ordinary Daguerreotype.” + +CRAYON DAGUERREOTYPES. + +This process is patented in the United States, by J. A. Whipple, of +Boston, and of course no honorable person will use it for his own +benefit without purchasing a right. + +A white back-ground is generally employed, the object being to blur the +lower portion of the plate, leaving the head of the subject in relief. +Every Daguerreotypist is familiar with the fact that a motion of any +body between the camera and the sitter will cause a “blur.” Cut a piece +of thin paper and scallop it, making a semicircle. This is kept +straight by means of a wire frame, and it is to be moved in front of +the lower part of the body of the sitter during the time of exposure of +the plate in the camera. Develop over mercury as usual, and the result +will be a crayon Daguerreotype. + +Another method is to have a wheel with a hole cut through it of a +diameter of about 12 inches. This hole is so cut as to leave teeth +resembling those of a large saw. This wheel is so arranged that it can +be turned around, which should be done during the time of exposure in +the camera. It must be placed between the camera and the sitter, and at +such a distance from the camera as to allow such proportion of the body +of the sitter be seen upon the ground-glass as is desired. It will be +readily seen that by turning this wheel during the operation will +produce the same result as the paper being moved in the other method. +The teeth make the “blur.” The side of the wheel towards the camera may +be black, by which means the result will be a dark instead of a light +border. + +ILLUMINATED DAGUERREOTYPES. + +This process is also patented, and the remarks on the preceding subject +will apply in this case. The plate is prepared and exposed as in the +usual method of the Daguerreotype. A white back-ground is employed. Let +the head of the sitter come in the middle of the plate, and before +exposing it to the vapors of mercury, put a small mat or diaphragm, +having a small hole through it, over or directly on the surface of the +plate. This diaphragm should be bevelled, and the bevel should be +towards the surface of the plate; this, in order to prevent too sharp a +line on the impression. It will be readily seen that if an impressioned +plate so covered is placed over the mercury, it will be developed on +such portions only as are exposed. The principle is so familiar that +further explanations are unnecessary. + +NATURAL COLORS IN HELIOGRAPHY. + +This subject is worthy the attention of every operator. The following +process is so plain and easy of trial that any Daguerreotypist can try +it. This is as given by Mr. James Campbell, and was published in +Humphrey’s Journal of the Daguerreotype and Photographic Arts, vol. 5, +page 11. Mr. Campbell has done much to further the process announced by +M. Neipce, and his experiments have proved highly successful. + +The following is submitted as worthy of trial: + +“The proper preparation of the chloridated plate, to enable it to +receive colored impressions is an object of the first importance to +those wishing to experiment on it, and consequently requires particular +notice. The plate may be prepared by making it the positive pole of a +battery, and letting it at the same time be immersed in chlorine water. +The negative pole should be a slip of platinum. All the colors may be +produced from a plate so prepared if the chlorine and water are in the +right proportions; but generally one color or the other predominates, +according to the amount of chlorine in the liquid. By adding the +chlorides of strontian, uranium, potassium, sodium, iron, or copper to +the liquid, various effects may be produced, and these bodies will be +found to produce the same color on the plate that their flame gives to +alcohol. + +“The honor of this discovery is due to M. Neipce. Copper gives a +variegated flame; hence many colors may be impressed on a plate +prepared with a solution of its chloride. + +“M. Neipce recommends a solution of the mixed chlorides of copper and +iron, and it is with these, that I have been most successful. As the +chlorides of copper and iron are not much used in the arts, they are +not generally found for sale in the shops; and it may be well to +furnish those not much versed in chemistry with an easy method of +preparing them. + +“They may be made directly from either metal by dissolving it in +hydrochloric acid; but they may be formed by a cheaper method, and by +which also the acid fumes are avoided. + +“Sulphate of iron or copper, or both together, may be dissolved in +water and then neutralized with common crude potash, or its carbonate +or bicarbonate—known commonly as pearl ash and saleratus. If either of +the latter be used, there will be formed sulphate of potash and a +carbonate of the metal used, and there will also be a considerable +effervescence of carbonic acid, which will, if care is not taken, cause +the mixture to run over the vessel. After the copper or iron salt is +neutralized, which is known by its ceasing to effervesce, the carbonate +of the metal will settle slowly, and will at first nearly fill the +vessel. The supernatant fluid, which is sulphate of potash in solution, +may now be carefully poured off, and its place filled with water; this +operation should be repeated several times until the water which passes +off is tasteless. The carbonate of the metal rapidly changes to an +oxide by contact with the air, and it will generally be found, when it +is sufficiently washed, that it is at least half oxide. On adding +hydrochloric acid cautiously to the mixture, a chloric of the metal +will be formed, and carbonic acid will be evolved from the remaining +carbonate. The chloride formed is soluble; but as there are two +chlorides of these metals, and we wish to produce the one which +contains the most chlorine, it is best to add the acid cautiously until +the solution is decidedly acid. After filtering the solution, it is fit +for use; and it should be preserved in well-stoppered bottles. The +water used should be rain or distilled water. + +“About one part of the mixed chlorides should be used to three or four +of water. + +“The battery may be either Smee’s, Daniell’s, or Grove’s; if of either +of the former, it should be of two series; if of the latter, one cup is +sufficient. + +“The plate on being immersed in the liquid, almost instantly takes a +violet color. It should be allowed to remain from two to five minutes, +according to the strength of the battery, and until it becomes nearly +black. It should now be carefully washed, and afterwards heated over a +spirit lamp until it takes a cherry-red color, and it is then ready for +exposure in the camera. Before speaking of exposing the plate, it may +be well to speak of some difficulties which the inexperienced operator +may find in preparing it. If the battery is not in good order, and a +sufficient current is not passed through the solution, the plate will +become coated—and apparently almost as well as when the battery is +working well—but on exposure it will give a negative picture, and but +little colored; while if the battery is in good order, the impression +is invariably positive. + +“Sometimes on heating the plate after washing, the surface is covered +with spots or assumes a variegated appearance. This indicates that the +solution is impure, or that the plate have not been thoroughly washed +and are still contaminated with the soluble chlorides which are +contained in the solution. + +“From the fact that the plate if prepared with positive electricity +gives a positive picture, while it prepared otherwise it gives a +negative, it is evident that electricity plays an important part in +this process. The same is true to some extent with the compounds formed +with iodine, bromine, and fluorine. + +“On heating the plate, the brown coating of chloride melts into a +translucent enamel, and the heat should be withdrawn when a cherry-red +color is produced. It the heat is continued longer, the plate assumes a +lighter color, and becomes less sensitive; and the enamel will finally +scale off. To produce a picture by the ordinary process of M. Neipce, +unaccelerated, it should be exposed for from three to five hours to +sunlight in the camera, though pictures may be procured by contact, in +from fifteen to thirty minutes.” + +MULTIPLYING DAGUERREOTYPES ON ONE PLATE. + +I have produced some interesting specimens of the Daguerreotypic art, +by exposing in the camera only a portion of the sensitive plate to the +action of light. When on the exposed portion an image is formed, then +taking the tablet into the dark room, change ends and expose the +sensitive portion, and produce another image, developing as usual. This +plan is adapted for taking likenesses for lockets. Two images can be +presented as sitting side by side, by covering half the plate with +black paper, and exposing as before. In this manner we have been +enabled to surprise persons by exhibiting their portrait on the same +plate with a stranger’s. Daguerreotypists must be cautious in +practicing this, as it might not be agreeable to the parties whose +likenesses are together, by the above process. It is impossible to +produce an impression without a line being seen where the edge of the +paper prevented the operation of the light. + +I have recently seen a fine specimen produced by another plan, which +far exceeds the above, there being no line, or any peculiarity denoting +two exposures. The specimen referred to, was a gentleman represented on +one plate by two full length portraits. This was produced by using a +black velvet for the background. The plate was exposed sufficient time +to produce one impression, and then the gentleman assumed another +position, and is repeated as looking at himself. From the fact that the +time required to develop black velvet being so much longer than that +for producing a portrait, we are enabled to produce the above +interesting results. + +DEPOSIT IN GILDING. + +Regarding specks from bad water, I would remark that gilding should be +made only with distilled water. Thus made, it produces very little +deposit, even by long keeping. It therefore preserves its original +strength, and works with great uniformity. + +Every grain of deposit contains at least 7-10 its weight of gold, +easily discoverable by the blowpipe. Such gilding is continually +deteriorating, which with good chloride and distilled water may be +prevented. Distilled water should also be used for the hyposulphite. +and for cleaning plates. Any good, clear water may be afterwards used +for washing off, with equally good results. I am very rarely troubled +with specs, and deem this as the main reason. + +With a portable still attached to a cooking stove, I obtain half a +gallon of water per hour, and with very little trouble. A small tin +retort or still connected with a Leibig’s condenser, would not add much +to the “traps” of the travelling operator, and save him many a +disreputable specimen.—T. J. BAILEY.—Humphrey’s Journal. + +PRACTICAL HINTS ON THE DAGUERREOTYPE. + +The following is from Humphrey’s Journal, vol. 5, and from the pen of +Dr. WM. HARRINGTON, one of the most able writers upon the subject of +the Daguerreotype in this country: + +THE CAUSE OF THE DIFFICULTY THAT SOMETIMES OCCURS TO PREVENT THE +PRODUCTION OF A CLEAR IMPRESSION UPON A DAGUERREOTYPE PLATE. + +Beyond all doubt this is traceable to dampness. Truly this is not a new +thought; but where does this dampness come from? How does it originate, +and where is it located? Generally it has been referred to a point +entirely remote from its real location. + +This dampness exists particularly upon the surface of the plate; is +obviously derived immediately from the atmosphere; and is owing to a +certain relative temperature of the plate with the hygrometric +condition of the atmosphere. + +Whenever this relation exists between the plate and atmosphere, a +precipitation of moisture takes place upon the surface of the plate, +which render all efforts at polishing impracticable. This interference +is not confined to the buffing operation alone, but sometimes is +discoverable even in the ordinary process of scouring. Every one at all +experienced in this art will remember that it is not always an easy +matter for him, by scouring, to bring his plate to the desired lustre. +All his efforts become unavailing; the more he rubs, the duller the +surface of his plate appears; and although he renews his cotton +repeatedly, still he is obliged to content himself with an +unsatisfactory finish. + +This relative condition is not confined to any particular season of the +year, nor to any certain thermometric temperature; but may occur in +summer as well as in winter; the weather being warm or cold, wet or +dry, clear or cloudy, raining or shining. Under any of these +circumstances, if the relation of the plate and atmosphere be such as +to invite upon the plate a precipitation of humidity from the +atmosphere, the prospect of producing a clear impression is quite +problematical. + +It is reasonable to expect this occurrence from the fact that metal is +a good radiator, and radiation reduces the temperature of a metallic +body below that of the atmosphere. Consequently, if this relative +condition happens, the result will be as I have stated. + +Bodies may be colder than the atmosphere and yet derive no moisture +from it; while at the same time the driest atmosphere is not devoid of +moisture, but will part with it under certain conditions. + +Assuming for granted that this relative condition between the plate and +atmosphere, disposing the former to receive the humidity of the latter, +constitutes the great obstacle the operator has to contend with in +producing, a clear proof upon the plate, the remedy naturally suggests +itself, and is very simple. It consists in merely heating the plate +above the temperature of the atmosphere, previous to polishing, and +retaining that temperature during the operation. Various measures might +be devised to effect the desired object; one of which consists of a +sheet-iron box, heated from the inside by a spirit-lamp, upon the top +of which are to be kept the plates ready to undergo the process of +being polished; the blocks of the swing or any other vice; or the iron +bed belonging to Lewis’s vice. + +In cold weather, when it is necessary to keep a fire in the preparation +room, all of the above may be so arranged in the vicinity of the fire +as to receive the requisite degree of heat for the purpose specified. + +This part of the subject, however, is left entirely for the ingenuity +of the operator. No matter by hat means he accomplishes the object; all +that is required is to heat the plate above the temperature of the +atmosphere and retain that heat during the process of polishing. + +Since the adoption of this method, in connection with my partner, T. J. +Dobyns, even in this humid climate of ours, when everything in the room +is dripping with moisture, it has been attended with invariable +success. + +CHOICE OF PLATES, ETC. + +In the great catalogue of complaints made by operators, none is more +common than that alleged against the quality of plates in general use. +Although the greatest diversity of opinion exists upon this subject, +nevertheless the plates of every manufactory share in this universal +condemnation. + +To be sure it cannot be denied but that this necessary article of +utility in the photographic art has undergone a sad deterioration in +quality owing to the increasing demand and great reduction in price—the +plates of the present day being by no means so heavily coated with +silver as formerly—but the complaint alluded to is not predicated so +much upon the thinness of silver as upon a mysterious something which +has conferred upon the plates the epithet of not good. + +That this complaint is in a great measure groundless appears evident +from the fact that while, with the same brand of plates one operator +can work successfully, another encounters the greatest difficulty; +while one is able to produce beautifully clear and altogether +satisfactory results, the other labors under the troublesome annoyance +of innumerable specks, large dark insensitive patches and brown +map-like portions, together with divers other blemishes, sufficient to +prevent him from obtaining anything like a tolerable impression. + +From this wide difference in the results of the two operators using +identically the same article, it is but reasonable to conclude that the +complaint is founded in error; while the inference is no more than +just, that the fault may be traced to a want of practical skill on the +part of the complaining operator himself; rather than to the inferior +quality of the plates. + +The question, then, whether the plates are unfit for use, or whether +those who pronounce them so understand how to use them, appears to be +satisfactorily answered. It therefore becomes a matter worthy of +investigation, to ascertain what superior judgment and skill one +operator possesses over another which enable him to work successfully a +quality of plate, pronounced by the other entirely useless. + +Suppose we make a critical examination of one of the repudiated plates. +From its external appearance we have little hesitation in pronouncing +it to be French; indeed, this presumption is strongly corroborated by +the fact that it is ornamented upon one of its corners with a brand to +designate the manufactory from which it emanated. + +Upon close inspection we cannot fail to notice a striking peculiarity +upon the surface; the roughness is very remarkable; the planishing +hammer has left amazingly visible indications of its busy work. One +would suppose the manufacturer intended the surface of the plate to +represent the undulations of the sea, instead of that smooth and level +character so strongly recommended by M. Daguerre. + +Such a plate necessarily requires at the hand of the operator +considerable labor before the surface is in a proper condition to +receive a suitable polish from the buffer. The least reflection in the +world should teach any one that so long as the undulatory character +continues upon the surface of the plate, it is in a very imperfect +condition for buffing, because the buffer cannot touch every point +equally; the elevated portions alone receiving a high degree of polish +while the depressed portion, from their roughness acting as nuclei, +gather dust, rouge, and other foreign bodies, so detrimental to +sensitiveness. The secret of the superior judgment and skill of one +operator over another, is intimately connected with this point: his +success depends very much upon the first process of cleaning the plate. + +Let us examine the manipulation of the complaining operator. He takes +one of these plates and gives it a careful scouring with rotten-stone +and alcohol or any other liquid preferred for this part of the +operation—that is, he gives it what he terms a careful scouring—very +gently indeed because, from the frequent trials he is in the habit of +making in the camera, he fears he will rub the silver entirely away +before he succeeds in obtaining a good impression. The dark patches, +specks, and granular appearance resulting entirely from the unevenness +of the surface of the plate, look like copper to him, and he is +surprised that he should have rubbed away the silver so soon, +particularly by such delicate handling. + +The judgment and experience of the successful operator, however, teach +him that scouring injures a plate less than buffing. He knows that +unless the hammer marks be obliterated, he cannot by the buffer produce +a surface of uniform polish and sensitiveness, without which a fair +proof is extremely doubtful; he knows that the time employed in the +preliminary operation of cleaning the plate properly is economy. + +There is a style of French plates in the market, denominated heavy, +which are truly excellent, if properly managed. Much patience, however, +is required to remove the marks of the hammer; but with tripoli and +alcohol the surface is readily cut down, and the plate is then +susceptible of a beautiful black lustre by polishing with the buffer. +The complaining operator could not succeed by his own method with one +of the plates; he would encounter all manner of clouds and other +unaccountable phenomena; he would imagine this plate entirely worn out +before it was half cleaned, and soon fix in his own estimation the +reputation of the heavy plate. + +In making a choice of plates, therefore, it would appear to be a matter +of perfect indifference with an experienced operator what kind he would +use, except so far only as the labor required in cleaning them was to +be taken into consideration. + +The distinction between a scale plate, a Scovill No. 1, S. F., heavy A, +star, crescent, eagle, or any other brand, consists in the superior +finish of some, and the thinness of the silver in the cheaper +qualities. + +Consequently, let the complaining operator but employ the diligence +inculcated in this article, to clean his plate thoroughly, so as to +bring it to a perfectly even and level surface, and he will seldom be +troubled with specks, clouds, dark patches, and the host of other +obstacles which heretofore have tormented him. + + + + +CHAPTER VI. + +AN ACCOUNT OF WOLCOTT AND JOHNSON’S EARLY EXPERIMENTS, IN THE +DAGUERREOTYPE. BY JOHN JOHNSON. + + +[From Humphrey’s Journal, vol. ii 1851] + +As a general thing, however perfect any invention may be deemed by the +inventor or discoverer, it falls to the lot of most, to be the subject +of improvement and advancement, and especially is this the case with +those new projects in science which open an untrodden field to the view +of the artisan. Such has been, in an eminent degree, the case with the +discovery first announced to the world by Mons. Jean Jaques Claude +Daguerre, of Paris, in the year 1839, and which excited unbounded +astonishment, curiosity and surprise. It may be questioned had any +other than Daguerre himself discovered a like beautiful combination, +whether the world would have been favored with details exhibiting so +much care, patience and perseverance as the Daguerreotype on its +introduction. Shortly after, these details reached the United States, +by Professor S. F. B. Morse, of New York, who was, at the time of the +discovery, residing in Paris. By this announcement, the whole +scientific corps was set in operation, many repeating the experiments, +following carefully the directions pointed out by Daguerre, as being +necessary to success. Among the number in the United States, was +Alexander S. Wolcott (since deceased) and myself; both of this city. On +the morning of the 6th day of October, 1839, I took to A. Wolcott’s +residence, a full description of Daguerre’s discovery, he being at the +time engaged in the department of Mechanical Dentistry, on some work +requiring his immediate attention, the work being promised at 2 P.M. +that day; having, therefore, no opportunity to read the description for +himself (a thing he was accustomed to do at all times, when +investigating any subject). I read to him the paper, and proposed to +him that if he would plan a camera (a matter he was fully acquainted +with, both theoretically and practically), I would obtain the materials +as specified by Daguerre. This being agreed to, I departed for the +purpose, and on my return to his shop, he handed me the sketch of a +camera box, without at all explaining in what manner the lens was to be +mounted. This I also undertook to procure. After 2, P.M., he had more +leisure, when he proceeded to complete the camera, introducing for that +purpose a reflector in the back of the box, and also to affix a plate +holder on the inside, with a slide to obtain the focus on the plate, +prepared after the manner of Daguerre. While Mr. Wolcott was engaged +with the camera, I busied myself in polishing the silver plate, or +rather silver plated copper; but ere reaching the end preparatory to +iodizing, I found I had nearly or quite removed the silver surface from +off the plate, and that being the best piece of sliver-plated copper to +be found, the first remedy at hand that suggested itself, was a +burnisher, and a few strips were quickly burnished and polished. +Meantime, the camera being finished, Mr. Wolcott, after reading for +himself Daguerre’s method of iodizing, prepared two plates, and placing +them in the camera, guessed at the required time they should remain +exposed to the action of the light; after mercurializing each in turn, +and removing the iodized surface with a solution of common salt two +successful impressions were obtained, each unlike the other! +Considerable surprise was excited by this result, for each plate was +managed precisely like the other. On referring to Daguerre, no +explanation was found for this strange result; time, however, revealed +to us that one picture was positive, and the other negative. On this +subject I shall have much to say during the progress of the work. +Investigating, the cause of this difference occupied the remainder of +that day. However, another attempt was agreed upon, and the +instruments, plates, etc., prepared and taken up into an attic room, in +a position most favorable for light. Having duly arranged the camera, I +sat for five minutes, and the result was a profile miniature (a +miniature in reality,) or a plate not quite three-eighths of an inch +square. Thus, with much deliberation and study, passed the first day in +Daguerreotype—little dreaming or knowing into what a labyrinth such a +beginning was hastening us. + +[Description of apparatus represented on pages 192 and 199:] + +A.—The Box—about 4 inches long by about 2 outside diameter. B.—The +Reflector soldered to a brass screw, and mounted in the rear of the +box. +c.—The slide to regulate the focus to the plate holder. d.—The standard +to the plate holder screwed to the slide. f.—The plate-holder frame +having two small ledges, * *, for the plate to rest upon. + +{192} + +g.—The plate resting upon the ledge., * *, and kept against the frame +by the spring h. The plates used were about 3/8 of an inch square. +A.—The window with the sashes removed. + +B and C (p. 199) are large looking-glasses mounted as plain reflectors, +the lower one C having rotary motion upon the saddle, resting upon the +sill of the window in order to direct the rays of the sun upon the +reflector B, at any hour of the day—the vertical motion of the +reflector C being necessary, the sun varying in altitude so much during +the hours most favorable to the production of portraits. The reflector +C was {193} kept up to the required position by the handle lever, +upright post and bolts. Reflector B was hinged at its upper end at the +top of the window frame, the only motion being necessary was that which +would reflect upon the sitter the incident rays from reflector C—the +reflector B being kept at the required angle by the connecting lever m, +etc. Suitable back-grounds were placed behind the sitter. + +[Illustration: Fig. 12] + +The reflector B and C, had frequently to be renewed, the heat of the +sun soon destroying their brilliance or power of reflecting, light, +before renewing them, however, we resorted to the springing of them, by +which means their power was increased for a period. + +The camera or reflecting apparatus, invented by Mr. Wolcott, was, from +the nature of the case, better adapted at that day to the taking of +portraits from life, than any other instruments. After carefully +examining the camera described by Daguerre, and the time stated as +necessary to produce action for an image, it became evident to the mind +of Mr. Wolcott at once, that more light could be obtained (as the field +of view required was not large) by employing a reflector of short focus +and wide aperture, than from a lens arrangement, owing to spherical +aberration and other causes. Many experiments having been tried with +the small instrument figured (p. 199), a reflector for taking portraits +from life was determined on, having eight inches diameter, with twelve +inches focal distance for parallel rays; this was to admit plates of +two inches wide by two and a half long Mr. Wolcott having on hand +reflectors of the right diameter, for Newtonian telescopes, of eight +feet focal distance, resolved (as it was a matter of experiment) to +grind down or increase the curve for the focal distance before +named—this required time. In the mean time, many plans were pursued for +making good plates, and the means of finishing, them. As the completion +of the large reflector drew to a close, our mutual friend, Henry Fitz, +Jr., returned from England, whither he had been on a visit, and when he +heard what we were about, kindly offered his assistance; he being well +versed in optics, and having been before engaged with Mr. Wolcott, in +that and other business is offer was gladly accepted—Mr. Wolcott +himself having frequent engagement; to fill as operator in the details +of mechanical dentistry. Thus, by the aid of Mr. Fitz, the reflector +was polished, and experiments soon after tried on plates of two by tow +and a half inches, with tolerable success. Illness on my part quite +suspended further trial for nearly four weeks. + +On my recovery, early in January, 1840, our experiments were again +resumed with improved results, so much so as to induce Mr. Wolcott and +myself to entertain serious thoughts of making a business of the taking +of likenesses from life, intending to use the reflecting apparatus +invented by Mr. Wolcott, and for which he obtained Letters Patent, on +the 8th day of May, 1840. Up to January 1st, 1840, all experiments had +been tried on an economical scale, and the apparatus then made, was +unfit for public exhibition; we resolved to make the instruments as +perfect as possible while they were in progress of manufacture. +Experiments were made upon mediums for protecting the eyes from the +direct light of the sun, and also upon the best form and material for a +back-ground to the likenesses. The length of time required for a +“sitting,” even with the reflecting apparatus, was such as to render +the operation anything but pleasant. Expedients were ever ready in the +hands of Wolcott: blue glass was tried and abandoned in consequence of +being, at that time, unable to procure a piece of uniform density and +surface: afterwards a series of thin muslin screens secured to wire +frames were prepared as a substitute for blue glass. The objections to +these screens, however, were serious, inasmuch as a multiplication of +them became necessary to lessen the intensity of the light sufficiently +for due protection to the eyes, without which, the likenesses, other +than profiles, were very unpleasant to look upon. Most of the +portraits, then of necessity were profiles formed upon back-grounds, +the lighter parts relieved upon black, and the darker parts upon light +ground; the back-ground proper being of light colored material with +black velvet so disposed upon the light ground, this being placed +sufficiently far from the sitter, to produce harmony of effect when +viewed in the field of the camera. Other difficulties presented +themselves seriously to the working of the discovery of Daguerre, to +portrait taking—one of which was the necessity for a constant and +nearly horizontal light, that the shaded portions of the portrait +should not be too hard, and yet, at the same time, be sufficiently well +developed without the “high light” of the picture becoming overdone, +solarized or destroyed. In almost all the early specimens of the +Daguerreotype, extremes of light and shade presented themselves, much +to the annoyance of the early operators, and seriously objectionable +were such portraits. To overcome this difficulty, Mr. Wolcott mounted, +with suitable joints, upon the top of his camera, a large looking-glass +or plane reflector, in such a manner that the light of the sun (as a +strong light was absolutely necessary), when falling upon the glass +could be directed upon the person in an almost horizontal direction. + +Early in February, 1840, Mr. Johnson, Sen., (since deceased) sailed for +Europe with a few specimen likenesses taken with the instruments +completed as above, with the intention of patenting the invention. On +his arrival a joint arrangement was effected with Mr. Richard Beard, of +London, in patenting and working the invention in England. Up to +February, 1840, but few friends had been made acquainted with the +progress of the art in the hands of Mr. Wolcott and myself. From time +to time reports reached us from various sources of the success of +others, and specimens of landscapes, etc., were exhibited at Dr. James +R. Chilton’s laboratory, in Broadway, much to the gratification of the +numerous visitors and anxious expectants for this most wonderful +discovery. Dr. Chilton, Professor J. J. Mapes, Professor J. W. Draper. +Professor S. F. B. Morse, all of this city; Mr. Cornelius, Dr. Goddard +and others of Philadelphia; Mr. Southworth, Professor Plumbe, and +numerous others were early in the field; all, however, using the same +description of camera as that of Daguerre, with modification for light, +either by enlargement by lens and aperture for light, or by shortening +the focal distance. + +At a conversational meeting of the Mechanics’ Institute, Professor J. +J. Mapes being present, a question was asked if any one present could +give information relative to portraiture from life by the +Daguerreotype. Mr. Kells, a friend of Mr. Wolcott and a scientific and +practical man (since deceased), at once marked out upon the +black-board, the whole as contrived by Mr. Wolcott. This gave publicity +to the invention of Mr. Wolcott. Shortly after, Professor Mapes, Dr. +Chilton, and many others, sat for their portraits, and were highly +gratified. Professor Morse also came and proposed to Mr. Wolcott to +join him in the working of the invention, etc. + +From this time much interest was manifested by our friends in our +progress. Rooms were obtained in the Granite Buildings, corner of +Broadway and Chambers street, and fitted for business. The rooms being +small, it was soon found impracticable to use the arrangement of +looking-glass, as previously spoken of; a new plan became necessary, to +introduce which, the sashes were removed, {199} and two large +looking-glasses were mounted in proper frames, thus:— + +[Illustration: Fig. 13] + +Just in front, and between the sitter and {200} the reflector, upon a +proper stand, were used those paper muslin screen before described; +also screens of tissue paper. These screens, however, when they were +used, required so much time for a sitting, that some other medium, as a +protection to the eyes, became absolutely necessary. The most plausible +thing that suggested itself was blue glass; but, as this could not be +found, numerous were the expedients proposed by the friends of the art, +who from time to time visited our rooms. At the suggestion of Professor +Mapes (who is ever ready to assist those in perplexity), a trough of +plate glass s, about twenty-eight inches square in the clear, and from +three to four inches thick, was filled with a solution of ammonia +sulphate of copper, and mounted on the frame as in the sketch, which, +for a time, answered extremely well; soon, however, decomposition of +this solution became apparent from the increased length of time +required for a sitting, although to the eye of an observer, no visible +cause for such long sittings could be pointed out. Professor Mapes +being appealed to, suggested that to the above solution a little acid +be added which acted like a charm—shortening the time for a sitting +from six, eight, or ten minutes to that of about one. Decomposition, +however, would go on by the action of light and heat through the +solution. New solutions were tried, when the whole were finally +abandoned as being, too uncertain and troublesome. (The reflecting +apparatus R, was placed upon the stand as in the sketch, with a wedge +for elevating the camera, between it and the table, to obtain the image +properly upon the plate.) A quantity of blue window glass was next +obtained, and holes drilled through the corners of it, and several +sheets were wired together to increase the size, and, when complete, +was suspended from the ceiling in its proper place, and so arranged +that when a person was sitting, this sheet of glass could be moved to +and from, the object of which was to prevent shadows on the face of the +sitter produced from the uneven surface of the glass. This latter +contrivance was used until a perfect plate of glass was procured. + +The number of persons desirous of obtaining, their miniatures, induced +many to entertain the idea of establishing themselves in the Art as a +profession, and numerous were the applications for information; many +persons paying for their portraits solely with the view of seeing the +manner of our manipulations, in order that they might obtain +information to carry on likeness-taking as a business. + +The reflecting camera being a very troublesome instrument to make, and +difficulties besetting us from every source, but little attention could +be given to teaching others; and, indeed, as the facts seemed to be at +this time, we knew but little of the necessary manipulations ourselves. +In course of time, several established themselves. The first one, after +ourselves, who worked the discovery of Daguerre for portrait taking in +this city, was a Mr. Prosch; followed soon after by many others, in +almost all cases copying the reflecting arrangement for light, as +figured above, many using it even after we had long abandoned that +arrangement for a better one. + +Innumerable obstacles to the rapid advance of the daguerreotype, +presented themselves almost hourly, much to the annoyance of ourselves, +and those dependent upon our movements for their advancement. Among the +most difficult problems of the day, was the procuring of good plates. +Messrs. Corduran & Co. were among the first to supply the trade; at +that early day, however, it was a very rare thing, to be able to +procure an even perfect surface, from the fact that a pure surface of +silver could scarcely be obtained, the manufacturers deeming it too +much trouble to prepare silver plated copper with pure silver—the +result was, that in attempting to polish perfectly such plated metal as +could be procured, the plates would become cloudy, or colored in spots, +from the fact of having more or less alloy, according as more or less +of the silver surface was removed in polishing the plate fit for an +impression. To explain more clearly, it was the practice of most silver +platers to use an alloy for silver-plating. In the reduction of the +ingot to sheet metal, annealing has to be resorted to, and acid pickles +to remove oxides, etc. The number of times the plated metal is exposed +to heat and acid in its reduction to the required thickness, produces a +surface of pure silver. The most of this surface is, however, so rough +as to be with difficulty polished, without in places removing entirely +this pellicle of pure metal, and exposing a polished surface of the +alloy used in plating. Whenever such metal was used, very unsightly +stains or spots frequently disfigured the portraits. The portrait, or +portion of it, developed upon the pure silver, being much lighter or +whiter than that developed upon the alloy; it therefore appeared that +the purer the silver, the more sensitive the plate became. Accordingly, +we directed Messrs. Scovills, of Connecticut, to prepare a roll of +silver-plated metal, with pure silver; it fortunately proved to be a +good article, but, unfortunately, a pound of this metal (early in 1840) +cost the round sum of $9. Like descriptions of metal, the same +gentlemen would be glad to furnish, at this time, for $4. Soon after +this, some samples of English plated metal, of a very superior quality, +came to our possession, and relieved us from the toil of making and +plating one plate at a time, an expedient we were compelled to resort +to, to command material to meet the pressing demands for portraits. + +Having it now in our power to obtain good plated metal, a more rapid +mode of polishing than that recommended by Daguerre was attempted as +follows: + +This metal was cut to the desired size, and having a pair of “hand +rolls” at hand, each plate, with its silvered side placed next to the +highly polished surface of a steel die, was passed and repassed through +the rolls many times, by which process a very smooth, perfect surface +was obtained. The plates were then annealed, and a number of plates +thus prepared were fastened to the bottom of a box a few inches deep a +foot wide, and eighteen inches long; this box was placed upon a table +and attached to a rod connected to the face plate of a lathe, a few +inches from its centre, so as to give the box a reciprocating motion. A +quantity of emery was now strewn over the plates, and the lathe set in +motion. The action produced wag a friction or rubbing of the emery over +the surface of the plates. + +When continued for some time, a greyish polish was the result. Linseed, +when used in the same manner, gave us better hope of success, and the +next step resorted to was to build a wheel and suspend it after the +manner of a grindstone. The plates being secured to the inner side of +the wheel or case, and as this case revolved, the seeds would +constantly keep to the lower level, and their sliding over the surface +of the plates would polish or burnish their surfaces. This, with the +former, was soon abandoned; rounded shots of silver placed in the same +wheel were found not to perform the polishing so well as linseed. +Buff-wheels of leather with rotten-stone and oil, proved to be far +superior to all other contrivances; and, subsequently, at the +suggestion of Professor Draper, velvet was used in lieu of buff +leather, and soon superseded all other substances, both for lathe and +hand-buffs, and I would add, for the benefit of new beginners that +those who are familiar with its use, prefer cotton velvet. The only +requisite necessary is, that the buffs made of cotton velvet should be +kept dry and warm. + +The greater number of operators, with whose practice I am familiar, +use, for polishing plates, prepared tripoli, imported from France, or +Browne’s rotten-stone. The former of these articles is very +objectionable, inasmuch as there is no positive certainty of being +enabled to procure or make the article of uniform grit—the nature of +the substance rendering, it impossible to reduce it to varying degrees +of evenness, by the well known process of washing, for that purpose, +and the burning of rotten-stone changes its chemical nature somewhat, +at the same time rendering, this invaluable article harsh and gritty. +And especially, no reliance can be placed upon burned rotten stone if +purchased from those who do not give very great attention and care to +its preparation; and the same remarks apply to rouge. + +The best article for polishing Daguerreotype plates is rotten-stone, +such as can be procured in any town, prepared after the following +manner: Procure, say half a dozen wide-mouthed bottles, of suitable +dimensions, numbering each from one to six. Put into No. 1 about half a +pound of rotten-stone, and nearly fill the bottle with water. Then, +with a proper stick or spatule, mix well the rotten-stone and water; +after which, let No. 1 rest for, say one minute, then carefully pour +off into bottle No. 2 (or, what would be better, draw off by a syphon) +as much of the floating particles of rotten-stone as is suspended in +the water. Again fill bottle No. 1 with water, agitate it as before, +and decant it to bottle No. 2, care being taken to draw off only the +suspended particles of rotten-stone. + +When a sufficient quantity of washings from bottle No. 1 is collected +into bottle No. 2, a similar process must be gone through, as above +stated, for No. 1; the difference being in the care required, and in +the time allowed between the stirring or mixing the rotten-stone and +water. The floating particles of rotten-stone, after four minutes’ +subsiding, will be found fine enough for the finest Daguerreotype +polishing required. + +A quantity of such washings may be collected in a large bottle, and +allowed to stand a few hours, when all the rotten-stone will have +settled. The water may be poured off and the rotten-stone put into an +evaporating dish, and while being dried, must be constantly stirred to +obtain an impalpable powder. + +Further washings may in like manner be resorted to for finer qualities +of rotten-stone. In my practice, I have used the articles at two and +four minutes’ settling, and occasionally have prepared it after +standing for eight minutes. So fine a quality as this, however, is +seldom required. In using, rotten-stone, I mix with it, for polishing, +fine olive oil, until I obtain a thin paste—and the best of all methods +for polishing (well planished) Daguerreotype plates, is one like that +used for glass by lens polishers; that is, by using a disc or +buff-wheel, and having, a suitable holder by which to secure the plate, +and then by pressing the plate against the revolving buff, well +saturated with the mixed oil and rotten-stone, a very good surface is +obtained. A quantity of plates may be prepared in this way, and all the +adhering oil, etc., may be removed by a clean hand, or lathe buff, +after which each plate must be heated to the point necessary to burn +off the remaining oil great care being required not to overheat the +plate. A very slight excess of temperature will at once destroy all the +polish previously obtained. The test for ascertaining the right +temperature is at hand; the adhering oil will be driven from the plate +in the form of smoke when the right temperature is reached. The moment +the smoke ceases to rise from the plate, the heat must be removed, and +the plate quickly cooled upon a piece of iron. + +A quantity of plates thus prepared may be kept on hand for any required +time, and the labor of one minute, with a lathe or hand-buff with dry +charcoal, or rather, prepared lampblack, will perfectly polish the +surface ready for indexing, etc. This lampblack also requires some care +in preparing. Take a small-size crucible, properly temper it by a slow +fire, that it may not be cracked after which, fill it with common +lampblack, cover it over with a piece of soap-stone, and again replace +it in the fire. Build a good hard coal fire around it continue the heat +for two or three hours, being careful not to raise the cover till the +crucible be quite cold. Pulverize when using it. It is very desirable +to keep this lampblack dry and warm. Some operators use much rouge I +would recommend the above in preference; but those who feel that they +cannot dispense with the use of rouge, had better try a large addition +of prepared lampblack to a small one of rouge, as this latter article, +unless great pains be taken in its preparation, will adhere and work +itself into the body of the surface, so that it cannot be removed +therefrom; and I have seen many specimens of Daguerreotype very much +injured in effect from this rouge tint disseminated throughout their +shaded features, at the same time that the whole general effect of such +pictures is that of a want of life. It is true that with the use of +rouge a very high degree of polish may be obtained, but probably not +higher than can be produced with many other substances of a less +objectionable nature. + +From the announcement of the discovery by Daguerre to the beginning of +the year 1840, I am not aware of any attempt to lessen the time for the +action of an image, or an impression, other than that of the reflecting +camera invented by Mr. Wolcott. Early, however, in 1840, Mr. Wolcott +was desirous to be enabled to further shorten the time for a sitting, +and having some knowledge of bromine and its action, by request, Dr. +Chilton prepared a small quantity; but Mr. Wolcott did not succeed very +well with it, he having invariably used too much in combination with +iodine to produce that sensitive coating now well known to the +profession. Professor Morse, of this city, Dr. Goddard, of +Philadelphia, and others, in the years 1840 and 1841, were acquainted +with the use of bromine. N. Griffing, of this city, or myself, used +with tolerable success, iodine in large excess to nitric acid and +water; and, subsequently, to nitro muriatic acid (which reacted and +formed a peculiar chloride of iodine); this latter combination proved +to be preferable to simple iodine, at the same time somewhat more +sensitive, and was used by me in this city up to the time of my leaving +for London (October 1, 1840). On arriving in London, I instituted a +series of experiments in the various chemical combinations, solely with +the view to be enabled to obtain more speedily a portrait than it was +practicable to do with any known chemicals at that date. The high +latitude, and the winter season of the year rendering but a feeble +light at best, the greater the necessity for a more sensitive chemical +preparation to the shortening the time for a sitting. Near the +beginning of the year 1841, I discovered and practically applied, +chloride of iodine to great advantage, and, as far as memory serves me, +I believe the first used in this country was some made and shipped, +Messrs. Harnden & Co., from London, to Mr. Wolcott, in New York. + +About the same time, Mr. John Goddard, of London (who was associated +with myself), discovered a rather valuable combination of chemicals, +consisting of a mixture of iodine, bromine, iodus, and iodic acid, and +a proper combination of those bodies gave an action somewhat more +sensitive than chloride of iodine—but the “high lights” of the +portraits would become solarized or overdone, more frequently with this +combination than with the chloride of iodine. Throughout the year 1841, +I used, with great success, chloride of iodine, applied as one +coating—occasionally in conjunction with Mr. Wolcott, attempting the +use of iodine, bromine, and chlorine, and at times with more or less +success. The difficulty of exactly combining, the three elements above +mentioned, in order to produce a certainty of result with harmony of +effect, was the work of many months, with great labor and study, the +slightest modification requiring a long, series of practical +experiments, a single change consuming, frequently, an entire day in +instituting comparisons, etc., etc. + +Early in the year, 1842, I discovered a combination of chemicals (now +known in London as “Wolcott’s Mixture,” in hermetically sealed bulbs) +of exceeding uniform character, very sensitive to the action of light, +and specimens produced in 1842-3, with this combination, will bear +comparison with the best specimens produced at this late date. + +About the same time, I discovered that however much overdone a +Daguerreotype might be, the means were at hand to save or redeem it. It +has long, since been known to operators, that if a plate be exposed to +light after being coated, unless it be again coated, a clear and +distinct picture could not be obtained upon the same plate without +first repolishing and recoating the same, care being taken that no +light fall upon the prepared surface. To prevent solarization, coat a +plate as usual, expose to the action of light any required time +(according to circumstances), say from quarter to one half more time +than would be required in the ordinary method of procedure; observe, +before putting the plate in the mercury box, place it over the vapor of +iodine, bromine, or chlorine, etc. (carefully excluding the light), for +a very brief period, great care being required to have the selected +vapor very much diluted with air, in order to success. Many experiments +will be required ere arriving at satisfactory results. Specimens now +unknown to general operators, for harmony of effect, have been, and may +again be produced by the method pointed out above. I have found the +best general effect, and the most certain result to follow from the use +of the vapor of chlorine—but this requires more than ordinary care. I +would, therefore, recommend the use of iodine. Thus: to a few grains of +iodine, add an ounce of warm water (which will become tinged with +iodine); when cold, to half a pint of pure water in a new and clean +coating box, put, of the above, fifty drops; stir and mix well this +small quantity of iodine in with the water; in ten minutes this box +will be ready for use. Great care and judgment will be required in the +application of this vapor to the plate; if the plate remain over the +vapor too long, the developed picture will have a faint and misty +appearance; if not exposed long enough, the “high light” will be +solarized. I have great hope of the ultimate use of this process, as it +is the only means yet discovered to be enabled to secure specimens of +extremes of light and shade, yet producing harmony of effect; and I +would call the attention of the profession to the fact, that a plate +may be exposed to the action of light for any length of time (a +thousand times longer than required to act for the lesser quantity of +mercury to deposit itself, or that amount necessary to form a perfect +specimen), and be restored by the application of any of the vapors +above mentioned, remarking that for extremes for solarization, denser +vapors will be required. Much remains to be done with this discovery to +the application of the Daguerreotype. + +HUMPHREY’S JOURNAL OF THE DAGUERREOTYPE & PHOTOGRAPHIC ARTS. + +The above-named publication is well known as the best and most valuable +one devoted to the Photographic Science in this country. Humphrey’s +Journal made its appearance November 1st, 1850, and consequently is the +first and oldest serial offered to the Photographic world. + +The art of producing Portraits and Landscapes by means of Light, has +recently taken a new and enlivening impulse, which will in all +probability lead to important and interesting results. No practical +Daguerreotypist, Photographer, or amateur, should be without the means +at hand for securing all of the information upon this subject. Each +should be ready to receive and apply the improvements as they may be +developed. In order to accomplish this, it is a matter of great +importance to the Practitioner or Experimenter that he should have a +reliable medium through which he can obtain information. In what source +can the inquirer better place his confidence than in a regular Journal, +whose editor is literally a practical person, and familiar with the +manipulations necessary for producing Portraits upon “Daguerreotype +Plates,” and upon glass and paper? Such is the conductor of Humphrey’s +Journal. + +This Journal is published once every two weeks, and contains all the +improvements relating to the Art, and is the only American Journal +whose editor is practically acquainted with the process for producing +Daguerreotypes, Ambrotypes, and Photographs. The first No. of Vol. X. +is dated May 1st, 1858. The terms (Two Dollars per annum) are trifling +compared with the vast amount of information furnished. + +AMBROTYPES.—Humphrey’s Journal contains everything novel which appears +upon this subject, and has already presented more new, important, and +original matter than can be found in any other place. + +Many are the letters we have received during the term of the last +volume, in which the writer has stated that a single number of +Humphrey’s Journal has contained information of more value to him than +“several times the amount paid for the entire volume.” + +Our resources have grown up around us, and our facilities for +procuring, as well as distributing, all such facts and improvements as +will benefit as well as instruct all who have the progress of the Art +at heart, are as ample as they can well be made. + +The future volumes will be abundantly furnished with original writings +from persons of standing in the scientific world; and the practical +Photographer will here find a full account of such improvements as may +from time to time develop themselves. + +From the editor’s long practical experience in the Heliographic +Science, he will be enabled to present the subject in a plain, clear, +and concise manner. + +Read what the Editors say of Humphrey’s Journal:— + +“We have received a copy of a valuable Journal (Humphrey’s) published +in New York, which has reached the 18th number of Vol. VI.... We now +have the pleasure of quoting from our trans-atlantic +coadjutor.”—Liverpool Photographic Jour. + +“Humphrey’s Journal is practical as well as scientific in +character.”—American Journal of Science and Arts. + +“It treats the subject knowingly and with force.”—New York Tribune. + +“It is both a popular and interesting publication.”—Mechanics’ +Magazine. + +“It is highly useful to all who practice ‘shadow catching.’”—Ohio State +Journal. + +“The work is neatly gotten up, and contains many interesting varieties +in this new field of science.”—Times. + +“It should be hailed and encouraged, not only by Daguerreotypists +themselves, but by every lover of Science and Art.”—The Democrat. + +“We cannot too strongly urge all artists, and those persons who feel an +interest in the Heliographic Arts and Sciences, to take a copy of the +work.”—Sentinel. + +“It is indicative of talent worthy of the important Art it is designed +to elevate.”—American. + +“This Art is entitled to its own organ, which could not have fallen +into better hands than those of the editor of ‘Humphrey’s +Journal.’”—Transcript. + +“It is a scientific work of interest and usefulness.”—Star of the +North. + +“This Journal answers many points heretofore regarded as +inexplicable.”—Hudson River Chronicle. + +“It is rich with interest.”—North American. + +“It contains all the ‘Improvements.’”—Delta. + +“It teaches us how to take our own portraits.”—Bee. + +“It will cultivate a taste for Daguerreotypes.”—Commercial Advertiser. + +“It should be in the hands of all.”—Reveille. + +“It is the Daguerreotypist’s friend.”—London News. + +“It should be found in every library.”—Evening Journal. + +From some of our Subscribers + +“Humphrey’s Journal has been the means of saving much time and money, +for by its instruction I have been enabled to produce some of the +finest Paper Pictures I have ever seen.” W. P. + +“Don’t fail to send me the Journal, for I would not be without it for +five times the amount of subscription. It is the only publication I can +depend upon.” A. G. R. + +“Your treatment of the humbugs and humbugging members of the +profession, is of the most valuable importance to us practical +Daguerreans. Go on. God speed! Here is the amount for the renewal of my +subscription.” E. F. S. + +“How can any Operator afford to be without it?” L. L. H. + +“Here are five dollars: send me Humphrey’s Journal to this amount. I +will not be without it.” M. S. + +“It is my best friend.” J. E. W. + +We might quote like commendatory extracts enough to more than ten times +fill this page. + +Humphrey’s Journal contains 16 octavo pages of reading matter. + +TERMS. + +One copy per annum, in advance . . . . . . $2 00 +Three copies, do. do. . . . . . . $5 00 +Six copies, do. do. . . . . . . $9 00 + +The thousands who read it cannot be induced to remain without it. All +who desire to keep up with the improvements should subscribe for a +copy. + +Subscription price Two Dollars per year. + +Don’t fail to become a subscriber. Address + S. D. HUMPHREY Office, 37 Lispenard Street, NEW YORK. + +THE PRACTICAL MANUAL OF THE COLLODION PROCESS. BY S. D. HUMPHREY. +THIRD EDITION + +This Edition contains all the Improvements in the Art made public up to +the day of publication, and gives complete Practical Instructions for +making Collodion Positives or Ambrotypes, Collodion Negatives, +Printing, etc., etc. The quick, great and unprecedented sale of the +first and second editions demonstrates, more than the strongest +language could possibly do, the extraordinary and increasing popularity +of this work. The Third Edition contains two hundred and sixteen 12mo. +pages, of a larger size and in smaller type than either of the +preceding editions, and is illustrated with numerous wood-cuts. It is +intended to be the best practical work extant; substantially bound in +cloth, price One Dollar; forwarded by mail (postage prepaid). Address + +S. D. HUMPHREY, New York + +A GUIDE TO PHOTOGRAPHY, + +Containing simple and concise directions for obtaining Views, +Portraits, etc., by the chemical agency of Light, by W. H. +Thornthwaite, author of “Photogenic Manipulations,” etc. Illustrated +with numerous wood-cuts. The Book contains more than one hundred 12mo +pages, bound in board, and is sold at twenty-five cents per copy, or +five copies for one dollar. Address + +S. D. HUMPHREY, New York + +HOLMES, BOOTH & HAYDENS, MANUFACTURERS OF DAGUERREOTYPE CASES, PLATES, +CAMERAS, MATTINGS, PRESERVERS, ETC., ETC. + +MANUFACTURERS AND IMPORTERS OF EVERY VARIETY OF AMBROTYPE, AND +PHOTOGRAPHIC GOODS, + +Of the Best and most approved Quality. + +ESPECIAL ATTENTION GIVEN TO THE FURNISHING OF EVERY ARTICLE USED IN THE +PRACTICE OF THE DAGUERREOTYPE + +Depot 81 Chambers and 63 Reade St., New York. + +Manufactory at Waterbury, Conn. + +HOLMES, BOOTH & HAYDENS’ CAMERAS + +From 1/4 to the Mammoth size. These CAMERAS are of the most superior +make, and all subjected to the most thorough test before being offered +for sale. + +VIEW CAMERAS, made expressly for taking views: an entirely new article. + +DAGUERREOTYPE PLATES, OF EVERY VARIETY, AND WE WOULD CALL PARTICULAR +ATTENTION TO THE + +Wreath, and H. B. & H. Eagle 40 Plates, AS HAVING NO EQUALS IN THE +MARKET. + +SOLE AGENTS FOR THE CELEBRATED H. B. AND N. P. FRENCH PLATES. + +Always on hand a complete assortment of Ambrotype and Photographic +goods. + +SOLE AGENTS FOR THE Patent solid glass corner Plate Holders. + +All orders will receive prompt attention, and be forwarded with +dispatch. + +HOLMES, BOOTH & HAYDENS, 81 Chambers, and 63 Reade St. New York. + +SCOVILL MANUFACTURING CO. + +MANUFACTURER OF DAGUERREOTYPE PLATES, MATTINGS, PRESERVERS, CASES, +APPARATUS, etc., etc. + +Importers and Dealers in every description of Daguerreotype, +Photographic, AND AMBROTYPE GOODS, + +The SCOVILL MANUFACTURING COMPANY flatter themselves that an experience +of nearly twenty years in the business and the most extensive variety +of the above Goods in the United States, entitle them to the +continuance of orders for the Domestic and Foreign trade, which will +receive the most careful attention. + +Park Building, New York. Entrances—36 Park Row, 4 Beekman, and 141 +Nassau Street. + +SCOVILL MANUFACTURING CO. + +Would call especial attention to their large variety of + +CASES, + +Embracing many Fancy Styles made only by themselves, and to which they +are constantly adding New Designs. + +Union Cases, Of all sizes, with Riveted Hinges. AGENTS FOR THE SALE OF +C. C. HARRISON’S CAMERAS, + +with improvements, which we are now prepared to sell at reduced prices, +and warranted to give better satisfaction than ever before +DAGUERREOTYPE PLATES, H. B.—N. P.—Star and other brands PLATE GLASS, +embracing three-quarters white: Crown and all other varieties. We would +call particular attention to our Black Glass, made expressly for +Ambrotypes. + +CHEMICALS, for the Daguerreotype and Photographic Art. Iodized and +Plain COLLODION. Gun Cotton, etc., etc. Tagliabue’s Collodiometres and +Actino-Hydrometres, for testing Chemicals. + +APPARATUS OF EVERY VARIETY. + +Gutta Percha, Porcelain, and Glassware of all kinds used in the Art. + +A large assortment of Gilt Frames always on hand and made to order. + +Ambrotype Shields, with solid corners of a new style. + +All orders will meet with prompt attention + +SCOVILL MANUFACTURING CO., PARK BUILDINGM New York 36 Park Row, 4 +Beckman, and 141 Nassau Street. + +HARDWICH’S PHOTOGRAPHIC CHEMISTRY AMERICAN EDITION. + +A MANUAL of PHOTOGRAPHIC CHEMISTRY, + INCLUDING THE PRACTICE OF THE COLLODION PROCESS. + +BY + +T. FREDERICK HARDWICH, + +LECTURER ON PHOTOGRAPHY IN KINGS COLLEGE, LONDON; LATE DEMONSTRATOR OF +CHEMISTRY IN KING’S COLLEGE. + +Last Edition, + +The above is the title of this new and valuable work. It is too well +known to need any further comment in this place. This volume contains +nearly 300 large duodecimo pages, bound in red cloth, $1.00. Copies to +be forwarded by mail, $1.18, postage pre-paid. + +S. D. HUMPHREY, Photographic Book Publisher, 37 LISPENARD +STREET, NEW YORK, + +N.B. Postage stamps taken. + + + + +End of the Project Gutenberg EBook of American Handbook of the Daguerrotype, by Samuel D. Humphrey + +*** END OF THIS PROJECT GUTENBERG EBOOK AMERICAN HANDBOOK OF THE DAGUERROTYPE *** + +***** This file should be named 167-0.txt or 167-0.zip ***** +This and all associated files of various formats will be found in: + http://www.gutenberg.org/1/6/167/ + +Produced by Gregory Walker, for the Digital Daguerreian Archive Project. + +Updated editions will replace the previous one--the old editions will +be renamed. + +Creating the works from print editions not protected by U.S. copyright +law 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. 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