Leather

—The skin of an animal converted into a durable and non-decaying substance, which is soft and supple for certain uses, firm and hard for others. There are three main proce es: (1) Impregnation of the hide or skin with tannic acid which combines with the gelatine to make an insoluble substance, this being used for sole leathers and the like; (2) treatment with alum or other mineral salts; as, for glove skins; (3) treatment with oils and fats; as, for chamois skins (shamoying). Heavy leathers are also tanned with chrome, principally for belting.