Under the term "textile" are included the fibrous substances that can be spun into threads, and woven or felted into cloth. Some of these, like the covering of the sheep, goat, and llama, or the cocoon of the silk-worm, are of animal origin; others, like cotton furze, the husk of the cocoanut, and the bast of the flax-plant are vegetable products. Their use in the manufacture of cloth antedates the period at which written history begins; it probably begins with the time when primitive man gradually ceased to have the hairy covering necessary to protect him from the conditions of climate and weather. As body coverings all these substances are dependent on a single principle, namely--they are poor conductors of heat; that is, they do not permit the natural heat of the body to pass away quickly, nor do they allow sudden changes of the temperature to reach the body quickly. In other words, because of the artificial covering which mankind alone requires, bodily heat is not dissipated more rapidly than it is created; if it were, the covering would be worthless. A suit of clothes made of steel wire, for instance, because it conducts heat so rapidly, might chill, or perhaps heat the body more quickly than the open air. With respect to warming qualities wool surpasses all other textiles. It is employed for clothing in every part of the world and by nearly all peoples. Cotton is used mainly also for body coverings, but it is inferior to wool for protection against cold. It is used by practically all peoples, savage and civilized, outside of the frigid zones. Linen is inferior both to cotton and wool for clothing; its use is also restricted by its great cost. Silk is used mainly for ornamental cloths. Hemp is used mainly for cordage, and the use of ramie, jute, and sisal hemp is confined mainly to the manufacture of very coarse cloths and rugs. =Cotton.=--The cotton fibre of commerce is the lint surrounding the seeds of several species of _Gossypium_, plants belonging to the same natural order as the marshmallow and the hollyhock. The cultivated species have been carried from India to different parts of the world, but cotton-bearing plants are also native to the American. A native tree-cotton, known as Barbados cotton, occurs in the West Indies; a herbaceous cotton-plant is known to have been cultivated in Peru long before the discovery of Columbus. [Illustration: COTTON-PRODUCING REGIONS] More than four hundred years before the Christian era Herodotus describes it and mentions a gin for separating the lint from the seed. Nearchus, an admiral serving under Alexander the Great, brought to Europe specimens of cotton cloth, and in the course of time it became an article of commerce among Greek and Roman merchants.