[DU CHATELET (Émilie)] Institution de Physique. Paris, chez Prault fils, 1740. in-12. 450 pp. 11 pl. Bound in basane, spine with 5 nerves, burgundy leather title-piece, ornamented caissons (wear, scratches, rubbing; a few tears in the edges; cuts in the upper parts of the hinges; second plate with beginning of tear). Soiling, some dampstaining and spotting, notably on title page; some worm damage (p. 227); plates sunned and stained. First edition of the first work composed by the marquise Du Châtelet (1706-1749), a mathematics enthusiast, at the instigation of Voltaire, whose mistress she was and who never ceased to support her scientific work. Provenance : Library of Auguste VERNEUIL (1856-1913), inventor of synthetic ruby.