"Touching."—The coloring of a photograph forms no part of my process: this is a matter to be given into the hands of an artist, and when it bears the finishing touch of his skill, it is no longer a photograph, but an oil or watercolor painting; all the delicate workings of nature having been lost or hidden under the colors.
A photograph may often be "touched" to advantage. If, as is frequently the case, there be little white spots on the face of the paper, they may be readily covered by the application of a little India ink, with the point of a wet pencil or fine small brush.
Mounting of Positives.
This, though a small matter in itself, is worthy of great attention. The durability of the proof depends much upon the purity of the paste used in causing its adhesion to the Bristol board. I have employed the following composition with the most eminent success:—
| Gum arabic | 2 | ounces |
| Gum tragacanth | 1½ | " |
| Isinglass | 1½ | " |
| Sugar | ½ | " |
| Water | 3 | pints |
These ingredients should all be dissolved, and then boiled down to the proper consistency, by means of a gentle heat.
I will give another composition, which will serve a good purpose, and keep for a long time:—
| Water | 8 | ounces. |
| One table spoonful of wheat flour | ||
| Powdered alum | 40 | grains. |
| Powdered resin | " | |
| Brown sugar | 1 | ounce. |
| Bichloride of mercury | 20 | grains. |
This last composition may be more convenient for operators, and it will answer the purpose well. It is thought by some to be the best and most durable paste yet prepared for the purpose.