Autograph manuscript signed ("Desmarest").
4to. 2½ pp. on bifolium.
Report to the French Academy of Sciences, co-authored and co-signed by the engineer and geographer Étienne Mignot de Montigny (1714-82), on the material properties of four leather samples and a pair of shoes. The samples had been provided to the Academy by the Parisian shoemaker M. Potot who claimed them absolutely impermeable to water due to special tanning and sewing techniques. Desmarest describes the samples and the different test arrangements. Both the samples and the shoes endured long-term exposure to water without soaking or leaking. The scientists also tested a comparison specimen tanned according to the "English method" which soaked within hours. As M. Potot provides certificates testifying to the durability and quality of his wares, Desmarest and Montigny do not see any necessity for further scrutiny. In conclusion, the scientists confirm the importance of Potot's methods and recommend them to the Academy's recognition, government protections and promulgation.
The geologist Desmarest was famous for his contributions to Diderot's Encyclopédie. He had been elected member of the Academy of Sciences in 1771; in 1788 he was appointed inspector of the manufactories.
Well preserved with a collector's mark in pencil (recto).