The hardened juice of several kinds of trees, It is also known by the names caoutchouc and elastic gum or resin. The india-rubber of commerce conies chiefly from Mexico, South America, Madagascar, and the East Indies. The East Indian rubber is the juice of a kind of fig-tree, while the South American is that of the syringe-tree. A hole is made in the bark, and the juice is caught in a cup. It is pale yellow in color, and about as thick as cream, but when spread out it hardens and becomes nearly pure white. Previous to the beginning of this century india-rubber was used only for rubbing out pencil marks, but now its uses are very numerous. All kinds of elastic and waterproof goods are made from it. It is woven with silk, cotton, or woollen threads into a great number of fabrics. The discovery of the art of vulcanizing rubber by the addition of sulphur, which was made by Charles Good-year, an American, in 1839, has largely added to its uses. Tubes, fire-hose, and gas-pipes, elastic rings or bands, door and window springs, mats, boots and shoes, machinery belts, and many other useful things are made out of vulcanized rubber, which does not soften in hot weather like common rubber. Hard rubber or ebonite is made out of india-rubber and sulphur heated much hotter than vulcanized rubber. Canes, combs, backs of brushes, buttons, surgical instruments, picture-frames, knife handles, and a great variety of other things are made from ebonite. India-rubber mixed with sulphur and coal tar makes a substance so hard and black that it resembles jet. This may be cut and polished and made into bracelets, breast-pins, sleeve-buttons, studs, watch-guards, and other useful and ornamental things.