| It may seem strange, at first thought, that Daguerre's own process is not familiarly understood by every disciple of the camera; but the fact is, very few professional photographers, and still fewer amateurs, are familiar with the working details of the process. This is undoubtedly because Daguerreotypy fell into disuse so many years ago, and before photography was practised at all as a pastime. It will be profitable, therefore, to at least briefly recall the beautiful old process at this time.|
Shortly after the details of Daguerre's invention were announced in the United States by Professor S. F. B. Morse, of New York, who was at the time of the discovery residing in Paris, American investigators commenced a series of experiments which resulted in considerably improving and advancing the new art. Some of the earliest workers in this field were Doctor Chilton, Professor J. J. Mapes, Professor S. F. B. Morse, of New York; Doctor Goddard, Mr. Cornelius, and others of Philadelphia; and Mr. Southworth, Professor Plumbe, Alexander S. Wolcott, and John Johnson.
The first plates were all made in France. They were of hammered copper, and silvered on one side by a process not generally known. They were originally made six and a half by eight and a half inches in size, and were then cut into halves and quarters. Thus originated the terms " whole" plate, "half" and "quarter" plate which are used at the present time in connection with gelatine emulsion plates. As soon as Americans began to manufacture copper plates for Daguerreotypy, they increased the size to eight by ten, which was called "extra whole size," and to eleven by fourteen, or "double whole size."
The Scovill Manufacturing Company, of Waterbury, Connecticut, were the first to manufacture Daguerreotype plates in this country. They were soon followed by Holmes, Booth & Haydens, and for some time's these were the only two American manufacturers of the copper plates. Mr. John Johnson speaks, in the second volume of Humphries Journal (1851), of some of the difficulties experienced in this country at first to obtain suitable plates: "It was a very rare thing to be able to procure an even surface," he writes, "from the fact that a pure surface of silver could scarcely be obtained. * * * Accordingly, we directed Messrs. Scovills, of Connecticut, to prepare a 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 grand sum of nine dollars."
These rolled-silver plates were prepared as follows: A thin plate of silver was soldered on one side of a brick of copper, and then rolled down thin. The plates were cut from the metal, stamped to flatten them, and then polished with rouge on a rag-wheel. The same method was employed by both the Scovill Manufacturing Company and Holmes, Booth & Haydens. The plates thus prepared were never superceded or improved for the purpose of daguerretypy, though many were the attempts made.
The plates coming from the manufactory were silvered on one side only, as was said, and, the silver coat being very light, they were always re-galvanized before actually being used. The plate was first thoroughly cleaned by rubbing it with finely levigated tripoli and a few drops of olive oil. A tuft of cotton or canton flannel was used for the purpose. Any oily matter left on the plate interfered with the subsequent operations, especially the galvanizing; so that alcohol diluted with water, and occasionally with a few drops of ammonia, was employed to remove the oil. After cleaning, the plate was buffed and re-galvanized. Buffing was accomplished in the following manner:
The cleaned plate was set in a moveable clamp in a heavy wooden block, on the lower side of which was a hole that fitted snugly to a pin projecting from a vice attached to a work-bench. Shive, of Philadelphia, made these blocks. The block and plate firmly secured, buffing was commenced. The first buffs consisted of a round piece of wood, covered with flannel and velvet, in which has been rubbed fine charcoal dust or rouge. Later this pad was replaced by the hand buffa stick of wood twelve to eighteen inches in length and three inches wide, and also covered with canton flannel, velvet, or soft leather. With the fine charcoal powder, or a nostrum sold at the time under the name of "Magic Buff," the work was done more effectively and with greater ease than at first. After the hand buff, came the buff-wheel, which was about twelve inches broad and thirty-six inches in diameter. The broad circumference of this wheel was covered with a very fine wash-leather, and rubbed in with rouge of the very finest quality. The wheel was generally propelled by means of a treadle, though, in a few instances, steam was employed. The plate was held against the rigid surface of the wheel till it was rubbed perfectly bright and free from scratches. It took several minutes to buff a plate thoroughly.
After the buffing, the plate was galvanized in an ordinary cyanide of potassium trough, with a silver anode and a Bunsen battery. When silver enough had precipitated upon the plate to give its surface a uniform bluish-gray color, the plate was removed from the bath, well washed, dried over a spirit lamp, and put away in a box for safe keeping.
Before sensitizing the plate it was again buffed with much care, dusted off and coated. Two boxes were used for the coating, one containing the iodine and the other the bromine. The plate was first subjected to the vapors of iodine until a sufficient amount of iodide of silver had formed, and then bromine fumes were applied, to accelerate. I. H. Cucher, one of the earliest writers on daguerreotypy, describes the method as used by most American operators. He says: "I tinge the plate over the first box containing the dry iodine, to a color from deep canary yellow to orange. In the second box, containing the dry bromine accelerator, the plate is given a deep purple or plum color, and" it is then repassed to the iodine box about half the time it took to produce the canary or orange color."
The bromine was used in either an aqueous solution, or dry. In solution, it never gained much favor among Americans. It was in the dry form, under the name of "Magic Quick," that it gained its immense popularity. It was prepared by saturating a pound of dry lime (burned oyster shells were much used), with ordinary alcohol, and then reduced to a perfectly dry powder. This powder was put in a glass-stoppered bottle, and shaken up well with an ounce of bromine. If the vapors of bromine were prevalent, more lime was added until all the bromine was neutralized and the powder assumed a reddish-brown color. The coated plate increased in sensitiveness by standing, but only to a limited degree. After several hours, the coated surface became spotted, and sensitiveness decreased.
When Daguerreotypy was practiced, lenses did not receive as much attention as they do now. The great object then was to produce a picture in the quickest possible time, and objectives of the very shortest focus and of immense diameter were, therefore, used.
After exposing the plate, it was developed by the vapors of mercury. The developing apparatus consisted of an inverted iron cone to the apex of which a bulb for holding the mercury was attached. One side of the developing apparatus had a thermometer divided into centigrades. When, from the heat of a spirit lamp, the thermometer indicated ninety degrees, the mercury began to evaporate, and developing could, therefore, be proceeded with. The open side of the cone was enclosed with an iron frame to which kits were fitted of the various plate sizes. In these kit frames the plates were placed for development.
After development, the plate was fixed with hyposulphite of soda, washed well, dried, put up in a neat velvet case, and finally delivered.
Gilding the plate was later practiced, and was considered a great improvement. It was accomplished by bending up the corners of the plate so that a miniature tray was formed capable of holding a certain amount of the gilding solution. This solution consisted of either a diluted mixture of chloride of gold and hypo-sulphite of sodium or a solution of a hypo-sulphite of gold and sodium, sold under the French name of "Sel d'or." After heating this solution tip to the boiling point, the plate was well washed, and dried by the heat of a spirit lamp. Gilded Daguerreotypes could be colored by dry dust colors, but this did not improve the artistic quality of the plate very much.
Our illustration gives a good idea of an old-time Daguerreotype establishment.
The days of Daguerreotypy have undoubtedly past never to return, but no one who has ever turned a buff-wheel or handled the coating boxes, will forget the pleasant and profitable times of the Daguerreotype.
(End of text. Please refer to our textnote regarding this text.)