Th�nard, Louis Jacques 1777-1857
French organic chemist and politician

Born in La Loupti�re, the son of a peasant farmer, he went to Paris in search of an education and attended lectures by Antoine Fran�ois Fourcroy and by Nicolas-Louis Vauquelin, who gave him a home in return for his services as a bottle-washer. In 1798 he was appointed demonstrator at the �cole Polytechnique; he later succeeded Vauquelin in the chair at the Coll�ge de France (1804), became Dean of the Faculty of Sciences of Paris (1821) and was Chancellor of the University of France (1845-1852). He was a prominent member of many public bodies, particularly those concerned with the application of science to industry, and received many honours culminating in a peerage in 1832. He also served two terms in the Chamber of Deputies. Th�nard made many important discoveries in organic chemistry and prepared a wide range of esters. He investigated cobalt and its compounds, and from alumina and copper arsenate prepared a stable brilliant blue pigment (Th�nard's blue) which was used in porcelain manufacture to replace the expensive pigments made from lapis lazuli. Between 1808 and 1811 he collaborated with Joseph Louis Gay-Lussac to study potassium and they discovered boron (1808). In 1818 Th�nard announced the discovery of hydrogen peroxide, perhaps his greatest achievement. His observation that finely divided metals acted on hydrogen peroxide to produce heat and hydrogen without themselves being affected, together with knowledge of Johann D�bereiner's work on platinum, led him to the study of surface catalysis. He was also the author of an influential textbook, Trait� �l�mentaire de chimie (4 vols, 1813-16, 'Elementary Treatise on Chemistry'), which went through six editions and was much translated.