Pow′der, a general name for pulverised or minutely divided solid substances, has come to be specifically identified with gunpowder, a mixture of sulphur, charcoal and potassium nitrate. Gunpowder is now used in war far less than formerly, owing to the superior advantages of smokeless powders; but the production of it is considerable, and there is little likelihood that it will be superseded for such purposes as fireworks and military and naval salutes. The origin of gunpowder is obscure. The use of it for military purposes was suggested by Roger Bacon about 1266. But gunpowder was known in India and China, where saltpeter is very abundant, from time immemorial. Gunpowder was used in cannons as early as the battle of Crécy (1346). Its quality was very gradually improved. The French took the step, under the direction of Lavoisier, of carefully pulverising the ingredients in separate wheel-mills. It was gradually discovered that the quality and purity of the ingredients, especially the charcoal and niter, need careful attention. The niter is purified and transformed into small crystals by a process of boiling in water, filtration and rotation in crystallising vessels. Willow-wood is commonly used for charcoal. Even the sulphur has to be distilled and finely powdered. The proportion of the ingredients may vary; but in military powder it often is 75 parts niter, 10 parts sulphur and 15 parts charcoal. The greater part of the powder now produced in the United States is used, not for guns, but for blasting. See Gunpowder.