The Encyclopaedia Britannica (11th ed.) article on dyeing, covering the history of the art from prehistoric times through the coal-tar dye discoveries of the 19th century. It classifies dyestuffs by method of application (acid, direct, developed, mordant, and miscellaneous colours such as indigo, aniline black and catechu) and describes dyebath procedures for wool, silk and cotton. It also covers natural dyestuffs such as madder and the dyeing machinery for loose fibre, yarn, cops and piece goods, illustrated with a vat, a cop-dyeing machine and a jigger. It ends with a bibliography of dyeing literature.