Swiss physician, electrical experimenter, geologist, mountaineer.

Professor of Experimental Philosophy at the Academy of Geneva (1762-86).

Visited England (1768), where he undoubtedly became acquainted with Franklin; both were fellows of The Royal Society.

Experimented on electricity and erected a lightning rod at his home in Geneva. Wrote the pamphlet, Exposition abrégée de l’utilité des conducteurs éléctriques (1771). Founded and presided over the Société des Arts de Genève (1772).

Franklin sent him a copy of the American Constitutions (1783).

Conducted experiments at high altitudes on temperature, the composition of air, atmospheric electricity, and balloons. Elected a foreign member to the Académie des Sciences de Paris (1790).

Published numerous scientific works including, De aqua (1771), Voyages dans les Alpes (1770-96), and Essai sur l’hygrométrie (1783).

Born in Conches, France.