MADDER or DYERS' MADDER, the root of Rubia tinctorum and perhaps also of R. peregrina, both European, R. cordtfolia, a native of the hilly districts of India and of north-east Asia and Java, supplying the Indian madder or manjit. Rubia is a genus of about 15 species of the tribe Galieae of the family Rubiaceae, and much resembles the familiar lady's bedstraw (Galium verum) and the cleavers (G. Aparine) of hedges and woodlands, having similarly whorled leaves, but the parts of the flowers are in fives and not fours, while the fruit is somewhat fleshy. The only British species is R. peregrina, which is found in Wales, the south and west of England, and in east and south Ireland. The use of madder appears to have been known from the earliest times, as cloth dyed with it has been found on the Egyptian mummies. It was used for dyeing the cloaks of the Libyan women in the days of Herodotus (Herod. iv. 189). R. tinctorum, a native of western
Europe, etc., has been extensively cultivated in south Europe, France, where it is called garance, and Holland, and to a small ex tent in the United States. Large quantities have been imported into England from Smyrna, Trieste, Leghorn, etc. The cultivation, however, has greatly decreased since alizarin, the red colouring principle of madder, was made artificially. Madder was employed medicinally by the ancients and in the middle ages. Its most remarkable physiological effect is that of colouring red the bones of animals fed upon it, as also the claws and beaks of birds. This appears to be due to the chemical affinity of phosphate of lime for the colouring matter. This property has been of much use in enabling physiologists to ascertain the manner in which bones develop, and the functions of the various types of cells found in growing bone.