The Boot and Shoe Manufacturers' Assistant and Guide. Containing a Brief History of the Trade. History of India-rubber and Gutta-percha, and Their Application to the Manufacture of Boots and Shoes. Full Instructions in the Art, With Diagrams and Scales, Etc., Etc. Vulcanization and Sulphurization, English and American Patents. With an Elaborate Treatise on Tanning.CHAPTER V.Chapter 1013 wordsPublic domainADULTERATION OF INDIA RUBBER (CAOUTCHOUC;) ENGLISH SYSTEM OF ADULTERATION FULLY PRESENTED, 145–164