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Towler, John. The Silver Sunbeam. Joseph H. Ladd, New York: 1864. Electronic edition prepared from facsimile edition of Morgan and Morgan, Inc., Hastings-on-Hudson, New York. Second printing, Feb. 1974. ISBN 871000-005-9

Chapter XXIII.
TRANSFER PROCESS OF COLLODION POSITIVES ON JAPANNED LEATHER, LINEN, PAPER, ETC.

BEFORE the preparation of the iron plates, known as Melainotype etc., the transfer process had more importance. A transferred positive has all the beauty of a melainotype, with the advantage of being non-inverted, and upon a medium that suffers less from being bent. It is especially suitable for inclosure in letters to distant friends. Any fine substance, as very thin leather, linen, paper, etc., neatly and evenly varnished with black Japan, is adapted for the reception of the collodion transfer. Such substances can be obtained from the wholesale dealers in photographic goods; they can also be prepared in the following manner: Take, for instance, a piece of fine leather, or oiled silk, and fix it on a stretcher, or flat board; then varnish it on one side with the following mixture.

Black Japan.

Chloroform, 8 ounces.
Asphaltum, 8 ounces.
Canada balsam, 2 ounces.

The ingredients when intimately mixed are poured in sufficient quantity upon the side to be japanned, and allowed to dry at a gentle heat. The varnish will soon set, and in a short time will be ready for the transfer operation. If metallic plates have to be japanned, such as the melainotype, that have to be introduced into the silver bath, they must previously be coated with common positive or negative varnish, in order to be prevented from exercising any injurious effect upon the silver bath, and afterward they are japanned on one side, as just described. These plates are not used in the transfer process, but to receive the image instead of glass.

The collodion on glass, when dry, or after it has been dried, adheres to the plate with considerable tenacity. The film for transferring, too, must be of the glutinous kind, containing more ether than alcohol. After the image has been fixed, and washed, and whilst the film is still moist, it is flowed with the following solution

Alcohol, 5 drachms.
water, 5 drachms.
Nitric acid, from 12 to 16 drops.

The solution is immediately poured off, and the plate drained of its superfluous fluid. The prepared leather, etc., is now cautiously laid upon the film, beginning in the middle, and allowing either end to fall gradually upon the collodion, so as to exclude all bubbles of air. The leather is next pressed with a burnishing tool all over the posterior surface, so as to bring it in intimate contact with the film beneath. If the operation be performed with dexterity and care, bubbles of air may be avoided; if any are observed, they must be removed by drawing up the leather gently before adherence takes place, and then by letting it down again with more caution. Having succeeded in bringing the collodion film and the leather in juxtaposition, without a single bubble, the plate is warmed gently over an alcohol-lamp, after which the leather can be removed, together with the collodion film adhering to it. The leather is now rinsed in pure water, and allowed to dry.

If it be desired that the collodion picture shall be in the form of an oval, circle, or square, etc., we proceed as follows: Place a mat with the proper opening upon the collodion picture, and with a pointed style go round the picture, cutting it as it were from the glass. All the collodion on the outside of this line is next removed with a piece of wood, as for instance, the end of a match cut to a flattened point, and made moist. By using this like a scraper, and keeping it moist, the collodion will gradually disappear, and the surface will be kept clean. The picture is afterward' transferred to leather, enamelled cloth, etc., by the method just described.

Transfer Paper.

Paper is prepared as follows for receiving the collodion positive. Dissolve

Asphaltum, 3 ounces in
Turpentine, 6 ounces.
Boiled oil, 8 ounces.

Afterward take--

India-rubber, (belting,) 1 ounce.
Camphene, 2 ounces.

Dissolve the latter by a gentle heat, and then add it to the first solution. Shake the solutions well together, and then allow the mixture to settle for a few days. It is afterward decanted into a dish. Ordinary unruled fine paper, in pieces of the proper size, is floated on this bath, and afterward hung up to dry. By repeating the process, the paper finally receives a very smooth surface. It will keep for any length of time. With a mixture of one ounce of alcohol, and three drops of nitric acid, moisten both the collodion film and the prepared paper surface, and pour the surplus back again into the bottle. Dip the plate and the paper into soft water several times; then, laying the plate on the table, place the paper upon the collodion positive in the manner already prescribed, in order to exclude bubbles; press them close together until the paper is quite smooth. The latter may now be raised, and removed from the glass, and dried.


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