who held appointments in Strasbourg (1849–54) and Lille (1854–57), before returning to Paris to the Ecole Normale and the Sorbonne. From 1888 to his death he was director of the Pasteur Institute. In 1848 he discovered optical activity, in 1860 relating it to molecular structure. In 1856 he began work on fermentation, and by 1862 was able to disprove the existence of spontaneous generation. He introduced pasteurization (originally for wine) in 1863. He went on to study disease and developed vaccines against cholera (1880), anthrax (1882), and rabies (1885).