Chemist, born at Strasburg; after a training at Carlsruhe and Leipzig, worked in Liebig's laboratory at Giessen; in 1838 he began lecturing in Paris, and made experiments along with Cahours on essential oils, which bore fruit in an important treatise; in 1844 he received the chair of Chemistry at Montpellier, but returned to Paris four years later; there he matured and published his theories of types, homologous series, &c., which have greatly influenced the science of chemistry; in 1855 he became professor of Chemistry in Strasburg (1816-1856).