China silk is thoroughly and carefully washed to free it from dressing, and then immersed in the following solution:

Sodium chloride. ... 4 parts

Arrowroot......... 4 parts

Acetic acid......... 15 parts

Distilled water...... 100 parts

Dissolve the arrowroot in the water by warming gently, then add the remaining ingredients. Dissolve 4 parts of tannin in 100 parts of distilled water and mix the solutions. Let the silk remain in the bath for 3 minutes, then hang it carefully on a cord stretched across the room to dry. The sensitizing mixture is as follows:

Silver nitrate....... 90 parts

Distilled water...... 750 parts

Nitric acid......... 1 part

Dissolve. On the surface of this solution the silk is to be floated for 1 minute, then hung up till superficially dry, then pinned out carefully on a flat board until completely dry. This must, of course, be done in the dark room. Print, wash, and tone in the usual manner.