Portrait of Berthollet

Claude-Louis Berthollet (1748–1822) was a Savoyard chemist (born in the Duchy of Savoy).
He is credited with discovering the bleaching properties of chlorine, from which he developed a method for bleaching fabrics using a solution of sodium hypochlorite: he thus invented bleach.
Appointments under the Ancien Régime: Member of the Academy of Sciences, Doctor-Regent of the Faculty of Medicine at the University of Paris, Director of Dyes at the Royal Gobelins Manufactory, member of the Royal Society.
Appointments during the Revolution: member of the Commission of Coins, member of the Commission of Agriculture, professor of chemistry at the École Normale and the École Polytechnique, member of the Institut de France. He also collaborated with Chaptal, Laplace and Monge in the founding of the École des Arts et Métiers.
He accompanied Napoleon Bonaparte during the Italian campaign and the Egyptian expedition.
He was made a Grand Officer of the Legion of Honour and was granted the title of Count of the Empire in 1808… but he voted for the Emperor’s deposition in 1814 and became a Peer of France during the Restoration.