JEAN ANTOINE CLAUDE, count of Chanteloup, was born at Nojalet Lozère in 1756. He early devoted himself to the study of medicine, and soon distinguished himself as a physician. His fame as a chemist had become so great, that he was called to Paris in 1793 to assist in the manufacture of gunpowder; and by his chemical knowledge and activity in the extensive factory at Grenoble, he was enabled to supply 3500 pounds per day. In the following year he returned to Montpellier, and received a place in the administration of the department of the Hérault, with the professorship of chemistry, which had been founded there for him. He was made a member of the Institute in 1798; and having favoured the revolution of the 18th Brumaire, he was made in 1799 a councillor of state by the first consul. In the year following he was appointed minister of the interior, in which capacity he greatly encouraged the arts and sciences, and established a chemical manufactory in the vicinity of Paris. In 1804 he fell into disgrace; the reason assigned for this being that he refused to state in one of his official reports that beet-root sugar was better than that prepared from the sugar-cane. In 1805, however, the emperor bestowed on him the grand cross of the legion of honour, and a seat in the conservative senate. On Napoleon's return from Elba he was appointed director general of commerce and manufactures, and a minister of state. On the downfall of the emperor he retired to private life, and in March 1816 the king nominated him a member of the Academy of Sciences. The various vicissitudes of fortune which he underwent never diverted his attention from science, which he continued to promote and encourage till his death, which took place at Paris in August 1832.

Chaptal was director of two chemical manufactories, at Montpellier and Neuilly. He discovered the application of old wool instead of oil in the preparation of soap, and the mode of dyeing cotton with Turkish red. He invented several kinds of cement and artificial puzzolanas, by means of native calcined ochre, as also new varnishes for earthenware, without the use of lead or plumago; and he extended the application of chemical agents in bleaching. Though Chaptal made no great or brilliant discoveries in chemistry, he was eminently distinguished as a practical chemist; and his new applications of known truths have greatly increased the obligations under which the arts lie to science.

He wrote Éléments de Chimie, 3 vols. 8vo, 1790; Traité sur la Sélèpère, 8vo, 1796; Essai sur le Perfectionnement des Arts Chinoises en France, 8vo, 1800; Art de faire, de gouverner, et de perfectionner les Puits, 8vo, 1801; Traité Théorique et Pratique sur la Culture de la Vigne, &c., 3 vols. 8vo, 1801; Essai sur le Blanchiment, 1801; Chimie appliquée aux Arts, 4 vols. 8vo, 1807; Art de la Teinture du Coton en France, 8vo, 1807; Art du Teinturier et du Dépositeur, 8vo, 1800; De l'Industrie Française, 2 vols. 8vo, 1819; Mémoire sur le Sucre de Betterave, 8vo; Chimie appliquée à l'Agriculture, 2 vols. 8vo, 1823.