| B. | Chrome alum | 0.25 parts |
| Water, hot | 20 parts | |
| C. | Alcohol | 10 parts |
When coated place the plates on a level stand until the gelatine is set, and let them dry on a rack.
Transparencies.—Prepare the plate as directed above with
| A. | Gelatine | 6 parts |
| Water | 70 parts | |
| B. | Chrome alum | 0.3 part |
| Water, hot | 20 parts | |
| C. | Alcohol | 10 parts |
Sensitize with the uranic-copper solution employed in the cuprotype. By this process transparencies of a rich brown, [pg 58] not actinic, color are obtained. Consequently they can be used to reproduce negatives by the same process. For lantern slides they may be toned black by platinic chloride.
To strip off the picture, apply, first, on the glass plate a substratum of India rubber, 2 to 100 of benzole, coat with plain collodion, immerse the plate in water as soon as the film is set, and when greasiness has disappeared pour on the gelatine solution and proceed.
For tranferring on any material, a sheet of paper is immersed in a solution of India rubber cement in 20 parts of benzole, dried, coated with the gelatine solution, sensitized, etc., by operating in the ordinary manner. After development, the proof, being dry, is brushed over with alumed gelatine moderately warm, dried, immersed in tepid water until the gelatine is softened and tacky, when it is placed on the material and squeezed into contact. This done, the transfer should be allowed to dry thoroughly. Now, by imbuing the proof with benzole to dissolve the India rubber, the paper is easily stripped off, leaving behind the picture adhering to the material.