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    Louis Joseph Proust. Autograph Letter Signed.
    "Proust." One page, in French, 6.75" x 8.25", n.d [circa 1806-1808]; n.p. [Paris?] In this letter addressed to Louis Augustin Guillaume Bosc (1759-1828), a French botanist, invertebrate zoologist, and entomologist, Proust asks him if letters from province [?] are being held by the postal service. Proust is concerned that a letter he wrote to Berthollet 15 days prior may have been lost; the letter would be of interest to the Commission on Grape Sugar. Adds that all are well and that his wife gives her warm regards to his entire family. Proust's reference to Claude Louis Berthollet (1748-1822), the French chemist known for his scientific contributions to theory of chemical equilibria via the mechanism of reverse chemical reactions, and for his contribution to modern chemical nomenclature, may relate to their longstanding professional disagreement (1803-1808) concerning the stability of the proportions of components in a given compound. Proust was eventually proven right. The letter also refers to a recent trip to Spain, where Proust extracted a specific sugar from grapes. When he returned to France in 1806 Napoleon offered him a large amount of capital to build a factory that would produce this sugar. Proust refused.

    Louis Joseph Proust (1754-1826) was a French chemist best known for his discovery of the law of constant composition in 1794, stating that chemical compounds always combine in constant proportions.

    Letter is accompanied by a handwritten French transcription and a printout of an English translation.

    Condition: Except for the usual folds and a slight tear on the left hand side, the letter is in good condition.

    Auction Info

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