Born in Paris, Guillaume Amontons took an interest in physics, architecture, and applied mechanics. He devised an external-combustion machine and was among the first to study problems due to friction in machines. In the field of scientific instruments, he introduced major improvements for hygrometers, barometers, and thermometers. Of special note is a "folded" barometer of his invention. Amontons is the author of Remarques et experiences phisiques sur la construction d'une nouvelle clepsidre, sur les baromètres, termomètres, & higromètres (Paris, 1695). The volume was dedicated to the Académie Royale des Sciences, of which he became a member a few years later.