History and Practice of the Art of Photography Part 7

A gentleman to whom it had been recommended, purchased a bottle, and after making one or two trials of it, wrote to his correspondent--"Send me two bottles of chloride of gold, for I want no more of the hyposulphite; it is good for nothing." A few weeks after he sent for three bottles of the condemned article, confessing that he had found fault unnecessarily; for, that since he had become familiar to its use, he must acknowledge its superiority, and would use no other gilding.

The Solution of Chloride of Gold is prepared by dissolving in a pint of distilled water, fifteen grains of chrystalized chloride of gold. This solution will be of a yellow tint. In another pint of distilled water dissolve fifty-five grains of hyposulphite of soda; pour gradually, in very small quant.i.ties, the gold into the hyposulphite of soda, stirring the solution at intervals; when finished the mixture should be nearly colorless.

Place the plate on its stand, or hold it in the plyers, in a perfectly horizontal position--silver surface upward--having previously slightly turned up the edges, so that it may hold the solution. Wet the surface with alcohol, letting any superfluous quant.i.ty drain off. The alcohol is of no farther use than to facilitate the flowing of the gold mixture over the surface. Now pour on, carefully, as much of the preparation of gold as will remain on the plate. The under part of the plate is then to be heated as uniformly as possible with the spirit lamp; small bubbles will arise, and the appearance of the portrait or view very sensibly improved. The process must not be carried too far, but as soon as the bubbles disappear the lamp should be removed, and the plate immersed in distilled water, and dried as before directed.

7th. COLORING THE PICTURE.--I very much doubt the propriety of coloring the daguerreotypes, as I am of opinion, that they are little, if any, improved by the operation, at least as it is now generally practised.

There are several things requisite in an artist to enable him to color a head, or even a landscape effectively, and correctly, and I must say that very few of these are possessed by our operators as a cla.s.s.

These requirements are, a talent for drawing--taste--due discrimination of effect--strict observance of the characteristic points in the features of the subject--quick perception of the beautiful, and a knowledge of the art of mixing colors, and blending tints.

The method now pursued, I do not hesitate to say, and have no fears of being contradicted by those capable of critisizing is on the whole ruinous to any daguerreotype, and to a perfect one absolutely disgusting. The day may come when accurate coloring may be obtained in the camera. Until that day, if we cannot lead taste into the right channel, we will endeavor to give such instructions that Daguerreotypists may proceed with this part of his work with a better understanding of the principles involved. For this purpose I have prepared a short chapter on the art of coloring, which may be found in the latter part of this volume.

To Preserve Daguerreotypes they must be well sealed and secured in a case, or frame. These, of course, are selected according to the taste of the customer, the princ.i.p.al requisite being good gla.s.s. Most Daguerreotypists prefer the white French plate gla.s.s--and many think, very erroneously, that none is good unless it is thick--but the great desideratum is clearness and freedom from blisters; even gla.s.s a little tinged with green or yellow is to be preferred to the French plate when cloudy or blistered and there is very little of it comes to this market that is not so. It is to be hoped that some of our gla.s.s factories will manage to manufacture an article expressly for daguerreotypes; and I would recommend them to do so, for they would find it quite an item of profit annually.

Before enclosing the picture in the case you should be careful to wipe the gla.s.s perfectly clean, and blow from the picture any particles of dust which may have fallen upon it. Then take strips of sticking paper, about half or three quarters of an inch wide, and firmly and neatly secure it to the gla.s.s, having first placed a "mat" between them to prevent the plate being scratched by the gla.s.s.

TO MAKE SEALING PAPER.--Dissolve one ounce of gum arabic, and a quarter of an ounce of gum tragicanth in a pint of water; then add a teaspoonful of benzoin. Spread this evenly on one side of good stout tissue paper; let it dry, and then cut it up in stripes, about half or three quarters of an inch wide, for use. If it becomes too soft for summer use, add gum arabic; if too hard and cracking, add benzoin or gum tragicanth; if it gets too thick, add water.

COLORED DAGUERREOTYPES ON COPPER.--To effect this, take a polished plate of copper and expose it to the vapor of iodine, or bromine, or the two substances combined; or either of them in combination with chlorine. This gives a sensitive coating to the surface of the plate, which may then be submitted to the action of light in the camera.

After remaining a sufficient time in the camera, the plate is taken out and exposed to the vapor of sulphuretted hydrogen. This vapor produces various colors on the plate, according to the intensity with which the light has acted on the different parts; consequently a colored photographic picture is obtained. No further process is necessary as exposure to light does not effect the picture.

By this process we have an advantage over the silvered plate, both in economy, and in the production of the picture in colors.

INSTANTANEOUS PICTURES BY MEANS OF GALVANISM.--It will be seen by the following valuable communication that galvanism can be successfully applied in producing pictures instantly; a process of great importance in securing the likeness of a child, or in taking views of animated nature. Colonel Whitney informs me that he once took a view of the steeple of the St. Louis Court House after sundown by this means, and also secured the image of a man in the act of stepping into a store, and before he had time to place his foot, raised for that purpose, on the door step. Mr. Whitney is well known as the talented editor of the Sunday Morning news.

New York, January 16, 1849.

Mr. H. H. SNELLING.

Dear Sir,--As you are about publis.h.i.+ng a history of the Daguerreotype, and request a description of my mode of taking pictures instantaneously by the aid of galvanism, I comply with great pleasure.

In the year 1841, while practicing the art in St. Louis, Mo., I was at times, during the summer, much troubled with the electric influence of the atmosphere, especially on the approach of a thunder-storm. At such times I found the coating of my plates much more sensitive than when the atmosphere was comparatively free from the electric fluid, and the effect was so irregular that no calculation could counteract the difficulty. This satisfied me that electricity was in some measure an important agent in the chemical process, and it occurred to me that the element might be turned to advantage. I determined, therefore, to enter on a series of experiments to test my theory. Finding it impossible to obtain an electric machine, and unwilling to abandon the examination, it occurred to me, that the galvanic influence might answer the same purpose. I therefore proceeded to make a galvanic battery in the following simple manner. I obtained a piece of zinc about two inches long, one inch wide, and an eighth of an inch thick.

On this I soldered a narrow strip of copper, about six inches long, the soldered end laid on one side of the zinc, and extending its whole length. The battery was completed by placing the zinc in a gla.s.s tumbler, two-thirds full of dilute sulphuric acid, strong enough to produce a free action of the metals. The upper end of the copper slip extending above the tumbler was sharpened to a point, and bent a little over the gla.s.s.

The method of using, was thus:--After preparing the plate in the usual manner and placing it in the camera, in such manner as to expose the back of the plate to view, the battery was prepared by placing the zinc in the acid, and as soon as the galvanic fluid began to traverse (as could be known by the effervescence of the acid, operating on the zinc and copper) the cap of the camera was removed, and the plate exposed to the sitter; at the same instant the point of the battery was brought quickly against the back of the plate, and the cap replaced instantly.

If the plate is exposed more than an instant after the contact the picture will generally be found solarized. By this process I have taken pictures of persons in the act of walking, and in taking the pictures of infants and young children I found it very useful.

Very respectfully yours, THOMAS R. WHITNEY.

CHAP. VII

PAPER DAGUERREOTYPES.--ETCHING DAGUERREOTYPES.

Mr. Hunt describes a process, discovered by himself by which the Daguerrean art may be applied to paper. His description is as follows:--

"Placing the paper on some hard body, wash it over on one side--by means of a very soft camel's hair pencil--with a solution of sixty grains of bromide of pota.s.sium, in two fluid ounces of distilled water, and then dry it quickly by the fire. Being dry, it is again washed over with the same solution, and dried as before. A solution of nitrate of silver--one hundred grains to an ounce of distilled water--is to be applied over the same surface, and the paper quickly dried in the dark. In this state the papers may be kept for use.

"When they are required, the above solution of silver is to be plentifully applied, and the paper placed wet in the camera, the greatest care being taken that no day light--not even the faintest gleam--falls upon it until the moment when you are prepared, by removing the dark slide, to permit the light, radiating from the object you wish to copy, to act in producing the picture. After a few seconds the light must be again shut off, and the camera removed into a dark room." The necessity of removing the camera is now avoided by the use of the dark slide, already described, covering the picture in the holder, which alone may be removed.--Amer. Aut.

"It will be found by taking the paper from the holder, that there is but a very faint outline--if any--yet visible. Place it aside, in perfect darkness until quite dry; then place it in the mercurial vapor box (meaning bath) and apply a very gentle heat to the bottom. The moment the mercury vaporizes, the picture will begin to develope itself. The spirit lamp must now be removed for a short time, and when the action of the mercury appears to cease, it is to be very carefully applied again, until a well defined picture is visible. The vaporization must then be suddenly stopped, and the photograph removed from the box. The drawing will then be very beautiful and distinct; but much detail is still clouded, for the developement of which it is only necessary to place it in the dark and suffer it to remain undisturbed for some hours. There is now an inexpressible charm about the pictures, equaling the delicate beauty of the daguerreotype; but being very susceptible of change, it must be viewed by the light of a taper only. The nitrate of silver must now be removed from the paper, by well was.h.i.+ng it in soft water, to which a small quant.i.ty of salt has been added, and it should afterwards be soaked in water only. When the picture has been dried, wash it quickly over with a soft brush dipped in a warm solution of hyposulphite of soda, and then wash it for some time in distilled water, in order that all the hyposulphite may be removed. The drawing is now fixed and we may use it to procure positive copies, (the original being termed a negative,) many of which may be taken from one original."

"The action of light on this preparation, does indeed appear to be instantaneous. The exquisite delicacy of this preparation may be imagined, when I state that in five seconds in the camera, I have, during suns.h.i.+ne, obtained perfect pictures, and that when the sky is overcast, one minute is quite sufficient to produce a most decided effect."

"This very beautiful process is not without its difficulties; and the author cannot promise that, even with the closest attention to the above directions, annoying failures will not occur. It often happens that some accidental circ.u.mstance--generally a projecting film or a little dust--will occasion the mercurial vapor to act with great energy on one part of the paper, and blacken it before the other portions are at all effected. Again, the mercury will sometimes acc.u.mulate along the lines made by the brush, and give a streaky appearance to the picture, although these lines are not at all evident before the mercurial vapor was applied. (A brush sufficiently large--and they may be easily obtained--will, in a measure, prevent this difficulty.--Amer Au.) I have stated that the paper should be placed wet in the camera; the same paper may be used dry, which often is a great convenience.

When in the dry state a little longer exposure is required; and instead of taking a picture in four or five seconds, two or three minutes are necessary."

The durability of daguerreotypes has been, and is still, doubted by many, but experiment has proved that they are more permanent than oil paintings or engravings.

ETCHING DAGUERREOTYPES.--There are several methods of accomplis.h.i.+ng this object; discovered and applied by different individuals.

The first process was published at Vienna by Dr. Berres, and consisted in covering the plate with the mucilage of gum arabic, and then immersing the plate in nitric acid of different strengths.

Mr. Figeau, of whom I have already spoken, likewise discovered a process for the engraving of Daguerreotypes; and founded on the belief that the lights of a Daguerreotype plate consists of unaltered silver, while the dark or shadows consists of mercury or an amalgam of mercury with silver. He finds that a compound acid, consisting of a mixture of nitric, nitrous, and muriatic acids, or of nitric mixed with nitrate of pota.s.s and common salt, has the property of attaching the silver in presence of the mercury without acting upon the latter. Bi-chloride of copper answers the purpose also, but less completely.

"When the clean surface of a Daguerreotype plate is exposed to the action of this menstruum, particularly if warm, the white parts, or lights are not altered, but the dark parts are attacked, and chloride of silver is formed, of which an insoluble coating is soon deposited, and the action of the acid soon ceases. This coat of chloride of silver is removed by a solution of ammonia, and then the acid applied again, and so on, until the depth of biting in is sufficient. However, it is not possible, by repeating this process, to get a sufficient force of impression; a second operation is required, in order to obtain such a depth as will hold the ink, to give a dark impression; for this purpose the whole plate is covered with drying oil; this is cleared off with the hand, exactly in the way a copper plate printer cleans his plate. The oil is thus left in the sinkings, or dark bitten in parts only. The whole plate is now placed in a suitable apparatus, and the lights or prominent parts of the face are gilt by the electrotype process. The whole surface is now touched with what the French engravers call the "Resin Grain," (grain de resine), a species of partial stopping out, and it is at once bitten in to a sufficient depth with nitric acid, the gilding preserving the lights from all action of the acid. The resin grain gives a surface to the corroded parts suitable for holding the ink, and the plate is now finished and fit to give impressions resembling aquatint. But as silver is so soft a metal that the surface of the plate might be expected to wear rapidly, the discoverer proposes to s.h.i.+eld it by depositing over its whole surface a very thin coat of copper by the electrotype process; which when worn may be removed at pleasure down to the surface of the n.o.ble metal beneath, and again a fresh coat of copper deposited; and so an unlimited number of impressions obtained without injuring the plate itself."

If, as has been a.s.serted, steel may be rendered sufficiently sensitive, to take photographic impressions, to what a revolution will the art of engraving be subject by the discovery of this process.

CHAP. VIII.

PHOTOGENIC DRAWING ON PAPER.

We shall now proceed to describe the various processes for Photogenic drawing on paper; first, however, impressing on the mind of the experimenter, the necessity which exists for extreme care in every stage of the manipulation. In this portion of my work I am entirely indebted to the works of Professors Hunt, Fisher and others.

I. APPARATUS AND MATERIALS.--Paper.--The princ.i.p.al difficulty to be contended with in using paper, is the different power of imbibition which we often find possessed in the same sheet, owing to trifling inequalities in its texture. This is, to a certain extent, to be overcome by a careful examination of each sheet, by the light of a candle or lamp at night, or in the dark. By extending each sheet between the light and the eye, and slowly moving it up and down, and from left to right, the variations in its texture will be seen by the different quant.i.ties of light which pa.s.s through it in different parts; and it is always the safest course to reject every sheet in which inequalities exist. Paper sometimes contains minute portions of thread, black or brown specks, and other imperfections, all of which materially interfere with the process. Some paper has an artificial substance given to it by sulphate of lime (Plaster of Paris); this defect only exists, however, in the cheaper sorts of demy, and therefore can be easily avoided. In all cases such paper should be rejected, as no really sensitive material can be obtained with it.

Paper-makers, as is well known, often affix their name to one half the sheet; this moiety should also be placed aside, as the letters must frequently come out with annoying distinctness. Well sized paper is by no means objectionable, indeed, is rather to be preferred, since the size tends to exalt the sensitive powers of the silver. The princ.i.p.al thing to be avoided, is the absorption of the sensitive solution into the pores; and it must be evident that this desideratum cannot be obtained by unsized paper. Taking all things into consideration, the paper known as satin post would appear to be preferable, although the precautions already recommended should be taken in its selection.

Brushes.--The necessary solutions are to be laid upon the paper by brushes. Some persons pa.s.s the paper over the surface of the solutions, thus licking up, as it were, a portion of the fluid; but this method is apt to give an uneven surface; it also rapidly spoils the solutions. At all events, the brush is the most ready and the most effectual means.

Distilled Water.--All the water used, both for mixing the solutions, was.h.i.+ng the paper, or cleaning the brushes, must be distilled, to obtain good results, for reasons before specified.

Blotting Paper.--In many instances, the prepared paper requires to be lightly dried with bibulous paper. The best description is the white sort. In each stage of the preparation distinct portions of bibulous paper must be used. If these be kept seperate and marked, they can be again employed for the same stage; but it would not do, for example, to dry the finished picture in the same folds in which the sensitive paper had been pressed. A very convenient method is to have two or three quarto size books of bibulous paper, one for each seperate process.

Nitrate of Silver.--In the practice of the photographic art, much depends on the nitrate of silver. Care should be taken to procure the best; the crystalized salt is most suitable for the purpose. While in the form of crystal it is not injured by exposure to light, but the bottles containing the solutions of this salt should at all times be kept wrapped in dark paper, and excluded from daylight.

II. DIFFERENT METHODS OF PREPARING THE PAPER.--Preparation of the Paper.--Dip the paper to be prepared into a weak solution of common salt. The solution should not be saturated, but six or eight times diluted with water. When perfectly moistened, wipe it dry with a towel, or press it between bibulous paper, by which operation the salt is uniformly dispersed through its substance. Then brush over it, on one side only, a solution of nitrate of silver. The strength of this solution must vary according to the color and sensitiveness required.

Mr. Talbot recommends about fifty grains of the salt to an ounce of distilled water. Some advise twenty grains only, while others say eighty grains to the ounce. When dried in a dark room, the paper is fit for use. To render this paper still more sensitive, it must again be washed with salt and water, and afterwards with the same solution of nitrate of silver, drying it between times. This paper, if carefully made, is very useful for all ordinary photographic purposes. For example, nothing can be more perfect than the images it gives of leaves and flowers, especially with a summer's sun; the light, pa.s.sing through the leaves, delineates every ramification of their fibres. In conducting this operation, however, it will be found that the results are sometimes more and sometimes less satisfactory, in consequence of small and accidental variations in the proportions employed. It happens sometimes that the chloride of silver formed on the surface of the paper is disposed to blacken of itself, without any exposure to light. This shows that the attempt to give it sensibility has been carried too far. The object is, to approach as nearly to this condition as possible without reaching it; so that the preparation may be in a state ready to yield to the slightest extraneous force, such as the feeblest effect of light.

Cooper's Method.--Soak the paper in a boiling hot solution of chlorate of potash (the strength matters not) for a few minutes; then take it out, dry it, and wet it with a brush, on one side only, dipped in a solution of nitrate of silver, sixty grains to an ounce of distilled water, or, if not required to be so sensitive, thirty grains to the ounce will do. This paper possesses a great advantage over any other, for the image can be fixed by mere was.h.i.+ng. It is, however, very apt to become discolored even in the was.h.i.+ng, or shortly afterwards, and is, besides, not so sensitive, nor does it become so dark as that made according to Mr. Talbot's method.

Daguerre's Method.--Immerse the paper in hydrochloric (or as it is more commonly called, muriatic) ether, which has been kept sufficiently long to become acid; the paper is then carefully and completely dried, as this is essential to its proper preparation. It is then dipped into a solution of nitrate of silver, and dried without artificial heat in a room from which every ray of light is carefully excluded. By this process it acquires a very remarkable facility in being blackened on a very slight exposure to light, even when the latter is by no means intense. The paper, however, rapidly loses its extreme sensitiveness to light, and finally becomes no more impressionable by the solar beams than common nitrate paper.