This section is from the book "A Treatise On Beverages or The Complete Practical Bottler", by Charles Herman Sulz. Also available from Amazon: A Treatise On Beverages.
1. (Bousquet's patented process.) Heat the corks to 100° C. (212° F.) in order to kill all spores -which they may contain. Then, while still hot, dip them into a solution of 1 part of albumen (egg albumen or blood albumen) in 200 parts of water, and afterwards into another containing 1 part tannic acid, 1/2 part of salicylic acid, and 200 parts of water. This causes a formation of tannate of albumen in the pores of the cork, and the salicylic acid, at the same time, acts anti-septically.
2. Make a solution of 4 parts of gelatin in 52 parts of water, and add to it, in the dark, or in a place illuminated with artificial (non-actinic) light, 1 part of bichromate of potassium or ammonium or sodium, previously likewise dissolved in water. Having first treated the corks with vapors of ether or benzol to render them thoroughly dry, dip them into the prepared solution, and then expose them several days to the sunlight, turning them carefully over so as to make the light fall upon every part of each cork. The coating of gelatin and chromic acid becomes insoluble under the influence of sun-light.