French geologist.

Inspector of manufactures (1762). Became interested in papermaking and toured Dutch paper mills (1768). Published two reports on papermaking (1771, 1774), followed by an article in Encyclopédie méthodique, Arts et Métiers méchaniques (1788) and a treatise on the subject, Art de la papétrie (1789). His technological innovations invigorated the French paper industry and greatly impressed Franklin. Desmarest’s geological discoveries included work on the origins of the English channel, the role of erosion in the formation of river valleys, and the volcanic origin of basalt. Elected to the Académie des sciences (1771); director (1786). Inspector general and director of manufactures in France (1788).

Son of a schoolmaster at Soulaines-Dhuys (Aube).