Carbons on Watch and Cigarette Cases, Watch Dials, China, Ivory and Celluloid.

336. Many pretty and permanent effects can be obtained by transferring carbons onto watch dials, china, ivory and celluloid. The process of making the print is exactly the same as for regular carbon work, with the exception that the double transfer must be employed. The picture having been developed on a temporary support is then transferred to any of these articles.

337. For a temporary support, that used in the ordinary carbon process is too heavy and not sufficiently flexible. As it is so thick and unyielding it would be impossible to press it into sufficiently close contact on a convex surface (for instance, a watch case) to obtain a perfect transfer. Even on flat surfaces it is next to impossible to obtain perfect contact, as the print is generally very small. For this reason, it is necessary to use a flexible and yielding support.

338. There are two different supports, either of which will answer the purpose. These are of India rubber or film of collodion. We recommend the collodion support. The collodion support has advantage over the rubber support, because it is transparent and enables you to see any air-bells which might gather, and also better enables the placing of the picture in the proper position. However, we will describe the making of both of these supports.

339. India Rubber Support

India Rubber Support. The India rubber support is prepared as follows: From a rubber store, obtain a can of India rubber solution. Thin this down with benzole to about the consistency of thin syrup. Place in a tray large enough to float the paper. The paper must be very thin-the thinner the better-but it must be able to withstand the warm water in development. Float the paper on the rubber solution for a few minutes and then hang up to dry. It is advisable to prepare this paper a few days before you wish to use it, so as to be sure that all solvents in the rubber have evaporated. If any of the solvents remain they will cause stains and spots in your print.

340. This India rubber support is used in exactly the same manner as the ordinary temporary support. The exposed tissue is squeegeed upon it in the regular manner, and the same methods employed for developing, washing and drying. You should, however, abstain from using the alum bath, as this would be apt to harden the surface, thus preventing successful transfer to the desired article.

341. Collodion Support

Collodion Support. To prepare the collodion support procure an ordinary glass plate, a little larger than the support you intend using. Clean this thoroughly, and when perfectly dry, dust over the surface, on one side only, with French chalk. Then wipe carefully with a soft, dry cloth, so as to remove all the chalk visible. Enough of this chalk will remain, although it cannot be seen. Next, coat this glass, chalked side, with ordinary enamel collodion (according to the formula given in the double transfer chapter), to which has been added negative cotton in proportion of three grains to every ounce of collodion, so it will produce a thick film. To coat the glass, hold the plate at the lower left-hand corner, between the fore-finger and thumb, with the lower edge of the plate resting on the third finger. Start the collodion at the top right-hand corner, flowing evenly over the entire plate, and drain back into the bottle.

342. After the collodion has become set (not dried) on the glass, the glass is placed, coated side up, in a tray of water and allowed to soak for ten or fifteen minutes, then placed under the tap, allowing a steady stream of water to fall on it, to thoroughly free it of the solvents in the collodion. The exposed tissue is squeegeed on to this, then set up to dry, and when dry can be stripped and trimmed in exactly the same manner as from the ordinary support.

343. The print is then ready for transferring to whatever article desired. After transferring, the collodion can be dissolved from the print with a mixture of one ounce of alcohol to one-half ounce of ether.