The origin of rubber

The substance called India Rubber, or Caoutchouc, was not known in Europe until the beginning of the eighteenth century. It was originally brought as a great curiosity from South America. Europeans continued ignorant of its origin until a deputation of the French Academicians undertook a voyage to South America in 1735, for the purpose of obtaining the correct admeasurement of a degree of the meridian. These philosophers did not confine their attention to the one great object of their pursuit, but among other interesting discoveries made themselves acquainted with that peculiar substance--caoutchouc. These Academicians discovered at Emeralds, in Brazil, trees called by the natives heve, whence flowed a juice, which, when dried, proved to be what is called India Rubber. The heve was also found growing in Cayenne, and on the banks of the Amazon river. It has since been discovered that caoutchouc may be obtained from another species of tree growing in South America, called jatropha elastica. If these trees are punctured, a milky juice flows out, which, on exposure to the air, thickens into a substance of a pure white color, having neither taste nor smell. The hue of the caoutchouc of commerce is black in consequence of the method employed in drying it. The usual manner of performing this operation is to spread a thin coating of the milky juice upon the moulds made of clay, and fashioned into a variety of figures. These are then dried by exposure to the heat of a smoke-fire: another layer is then spread over the first, and dried by the same means; and thus layer after layer is put on, until the whole is of the required thickness. While yet soft it will receive and retain any impression that may be given to if on the outside. When perfectly dry the clay within is broken into small fragments by percussion, and the pieces are drawn out through the aperture which is always left fur the purpose. The common bottle of India Rubber, therefore, consists of numerous layers of pure caoutchouc, alternating with as many layers of soot.
The natives of those parts of South America to which these trees are indigenous, convert the juice to a variety of purposes. They collect it chiefly in the rainy season, because, though it will exude at all times, it flows then most abundantly. Boots are made of it by the Indians, through which water cannot penetrate; and the inhabitants of Quito prepare a kind of cloth with it, which they apply to the same purposes as those for which oil-cloth or tarpaulin, it used here. This, no doubt, is similar to the cloth now prepared with this substance in America, the use of which yields so many important advantages.--Youths' Gazette.
-Scientific American, Vol 2, No. 1