Phélypeaux, Jean-Frédéric, comte de Maurepas: [Canada]:

$750 · Offered by William Reese Company

[AUTOGRAPH LETTER, SIGNED, FROM THE COMTE DE MAUREPAS, REQUESTING NEW SCIENTIFIC INSTRUMENTS ON BEHALF OF GILLES HOCQUART, INTENDANT OF NEW FRANCE]. An entertaining letter written in 1745 by French minister Jean-Frédéric Phélypeaux, Comte de Maurepas, to scientist Henri-Louis Duhamel du Monceau at Versailles requesting on behalf of Gilles Hocquart, the Intendant of New France in Canada, that new thermometers and other scientific instruments be sent to Quebec. The author notes that although the old thermometers were graded to measure temperatures down to -15 on the Réaumur scale, it had in fact only recently been -27 or -28 . Even if the thermometers had been able to measure temperatures that low, according to Maurepas, the cold had caused the measuring liquid inside the instruments to separate permanently, rendering them useless in any event. He therefore asks that four new Réaumur thermometers capable of measuring down to -35 be sent, along with several astronomical instruments for making navigational observations.

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