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diff --git a/old/amdag10.txt b/old/amdag10.txt new file mode 100644 index 0000000..11c5d9e --- /dev/null +++ b/old/amdag10.txt @@ -0,0 +1,5099 @@ + +Project Gutenberg Etext of American Handbook of the Daguerreotype + +Please take a look at the important information in this header. +We encourage you to keep this file on your own disk, keeping an +electronic path open for the next readers. Do not remove this. + + +**Welcome To The World of Free Plain Vanilla Electronic Texts** + +**Etexts Readable By Both Humans and By Computers, Since 1971** + +*These Etexts Prepared By Hundreds of Volunteers and Donations* + +Information on contacting Project Gutenberg to get Etexts, and +further information is included below. We need your donations. + + +American Hand Book of the Daguerreotype by Samuel D. 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FOR PUBLIC DOMAIN ETEXTS*Ver.04.29.93*END* + + + + +The Project Gutenberg Etext of American Hand Book of the Daguerreotype + +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 TAKINGHELIOGRAPHIC 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.* + +*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 +onehalf 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 aplate 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,* who seems to think the truth of the picture exists +principally in the eyes staring the beholder full in the face. + +* 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 submittedto +the o peration 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 beveltop 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*; 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. + +* 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." + + + +MISCELLANEOUS. + +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. + +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. + + + +CHEMICALS. + +CHAPTER III. + +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. + +[page 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 + +[page 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 + +[page 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 thep recise 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, + +[page 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. + +[page 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.*--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. + +* 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 bas 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 (l849) 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 l5 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. + + + + +LIGHT AND OPTICS. + +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. + +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. + +[page 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. + +[amdg_1.gif] + +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 + +[page 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. + +[amdg_2.gif] + +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: + +"If the linear measure, or the diameter of a circle which shall +include the luminous rays, + +[amdg_3.gif] + +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. + +[amdg_4.gif] + +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:-- + +[amdg_5.gif] + +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. + +[amdg_8a.gif] + +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 + +[amdg_9.gif] + +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 l/l6 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." + +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: + +[amdg_10.gif] + +"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, + +[amdg_11.gif] + +or meniscus, which corresponds more nearly to the accompanying diagram." + +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. + +If L L be a double convex-lens, and R R R parallel rays of white light, +composed of the seven colored rays, + +[amdg_8b.gif] + +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 +uniform]v 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 m 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 pearlash 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 185l] + +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. + +[page 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 + +[amdg_12.gif] + +being necessary, the sun varying in altitude so much during +the hours most favorable to the production of portraits. +The reflector C was + +[page 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. + +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 +(sinced 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, + +[page 199] + +and two large looking-glasses were mounted in proper frames, thus:-- + +[amdg_13.gif] + +Just in front, and between the sitter and + +[page 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 he 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 offord 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 T0 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 CALI. +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 BUILDING + 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 Etext of American Hand Book of Daguerreotype + + + |