French experimental physicist and clergyman. He worked with Dufay and Reamur. In 1740 he was admitted to the Paris Academy of Science. In 1753 he became the first Chair of experimental physics at the College of Navarre, Paris.He manufactured scientific instruments and invented the electrometer, a device for detecting and measuring electrical charges. He developed a theory of electrical attraction and repulsion that supposed the existence of a continuous flow of electrical matter between charged bodies. His published research included the effects of temperature and humidity on electrical discharges and the effects of electrical discharges on the growth of plants and animals.He was the first to observe and describe osmosis.He was a leading figure in the popularisation of experimental science in France. Here he is conducting a Physics Course at the College of Navarre in 1754.