Chaptal’s development of industrial chemistry in France lies at the heart of a much broader programme of influential progressive reforms. He was a senior member of Berthollet and Laplace’s Société d’Arcueil, and succeeded Berthollet at the École Polytechnique. He appointed Vauquelin as director of the school of pharmacy, provoked Thénard’s development of cobalt blue pigment, and was among those Carnot worked with to get enlightened technical policies enacted. Berthollet, Monge and Laplace were particularly close friends, visiting him at the château he restored where he produced beet sugar and eau-de-vie.