Letter from Simeon Denis Poisson to Thomas Young, dated at Paris Sends 5 copies of a paper on elastic bodies and fluid flows via the booksellers Payne and Voss [Clarification: this paper contains the first proof of the divergence theorem]. 1 copy should be presented to the Royal Society, another for Young and the names of the intended other 3 recipients are inscribed on the title page. Comments on how he arrived to the formulations in the paper. In postscriptum, notes that diamonds the size of a grain of oat and with three faces were presented at the latest séance de l'Académie des sciences by [Charles Cagniard de la Tour], [Jean Dominique] Arago will use them to verify the angle of polarization. 12 November 1828