Carangeot, Arnould

(b. Rheims, France, 12 March 1742; d, Meaux, France, 18 November 1806),

crystallography, entomology.

Carangeot was the son of Ponce Carangeot, a weaver, and his wife, Liesse Tellier. He was educated in an unimportant seminary; but at the age of twenty, he went to Paris, where his integrity and orderliness won him several patrons who made him their business manager. The fashionable bourgeois whom Carangeot served were deeply interested in the natural sciences; thus, the young administrator dedicated a great deal of his leisure time to studying botany, mineralogy, and entomology.

In 1772, Carangeot’s teacher, Romé de L’Isle, published Essai de cristallographie ou Description des figures géométriques propres à différens corps du règne minéral connus vulgairement sous le nom de cristaux, in which he emphasized those characteristics that define mineralogy as an individual discipline. The success of this work encouraged Romé de L’Isle to prepare a much enlarged second edition, which included 438 illustrations of minerals from his extensivecollection. Further, he commissioned the engraver Swebach-Desfontaines to reproduce these minerals in terra-cotta, which reproductions were to be sent as premiums to subscribers.

Swebach asked for clay models from which to work, so Romé de L’Isle asked Carangeot and ClaudeLermina to fabricate them. In so doing, Carangeotexperienced some difficulty in measuring the dihedralangles of a quartz sample; he was thus inspired to construct a goniometer—a device combining thequalities of the proportional compass and the pro-tractor. Carangeot’s prototype measured seventy-eightmillimeters in exterior diameter. Carangeot then asked Nicolas Vinçard, an engineer who specializedin mathematical instruments, to build two models of this new gauge (one was of silver, and cost thirty-six livres, while the other, of copper, cost half as much).

On 11 April 1782, Carangeot presented the goniometer to a group of scientists and artists assembledby Pahin de La Blancherie. Through the use of thisinstrument, he was the first to observe the invariabilityof dihedral angles in mineral species. When Vinçard died in 1788, his assistant, Jean-Bapliste-PierreFrançois Férat, continued to manufacture Carangeot’s goniometer, which was then duplicated by Richer and others.

Carangeot is also known as an entomologist, When the financier Gigot d’Orcy published the Papillonsd’Europe peints d’après nature, Jacques-Louis-Florentin Engramelle wrote the text for the first threevolumes (1779–1784) and Carangeot wrote the text of volumes IV through VIII (1785–1793).

Although Carangeot remained in Paris throughoutthe Revolution, he avoided all and any participationin public life. On 10 August 1785 he was elected anassociate member of the Académie de La Rochelle; on 13 April 1798 he was named curator of the museum at Meaux, where he founded and became permanent secretary of the Société d’Agriculture, Sciences et Arts of Seine-et-Marne.

BIBLIOGRAPHY

I Original Works. Carangeot’s writings include “Un goniomètre ou mesure-angle,” in Nouvelles de la République des lettres et des arts, no. 14 (17 April 1782), 111; “Goniomètre, ou mesure-angle,” in Observations sur la physique, sur l’histoire naturelle et sur les arts, 22 (Mar.1783), 193 197; “Lettre… à M. de La Mètherie sur legoniomètre.” ibid., 29 (Sept. 1786), 226–227; “Lettre à M. Kaestner… sur de prétendues erreurs dans la description du goniomètre,” ibid., 31 (Sept. 1787), 204–206; Papillons d’Europe peints d’après nature, IV-VIII (Paris, 17851793); “Lettre au rédacteur,” in Journal des mines, no. 25(an V), 78–80; Réflexions sur les musées et leur organisation (Meaux, an VIII; 2nd ed., Meaux, 1901); and Principes delecture (Meaux, 1810).

II. Secondary Literature. For Carangeot’s life and work, see also A. Birembaut, “Les frères Engramelle,” in Actes du VIIIe Congrès international d’histoire des sciences (Florence), I (Paris, 1958), 149–155; and R. Homberg, “Some Unknown Plates in Ernst and Engramelle’s ‘Papillons d’Europe peints d’après nature,’ 1779–1793,” in The Journal of the Society for the Bibliography of Natural History, 3 (1953), 28–53.

The 2nd ed. of Carangeot’s Réflexions sur les musées.… (Meaux, 1901) contains introductory biographical material by A. Le Blondel (pp. 3–7) and S.-N. Guyardin (pp. 9–14).

Arthur Birembaut