Antoine Deparcieux (1703-1768), French mathematician, also known as Antoine de Parcieux (as seen in the French inscription). Deparcieux, who started his career in Paris in 1730, is best known as the founder of the study of human longevity. His best known work is Essai sur les probabilites de la duree de la vie humaine (Essay on the probabilities of the human lifespan, 1746). He was a member of numerous academies of science, and was designated Royal Censor in 1765. He also invented several water pumps. Published in 1777, this is an etching and engraving by Benedict Alphonse Nicolet (1743-1806) of an artwork by Charles Nicholas Cochin (1715-1790).