TROUVELOT, ÉTIENNE LéOPOLD

(b. Guyencourt, Aisne, France, 26 December 1827; d. Meudon, France, 22 April 1895)

natural history, astronomy.

A keen observer and skillful artist, Trouvelot spent several years (1872 – 1874) working with the fifteen-inch refractor at Harvard Observatory. The drawings he made there and elsewhere are still widely known. Except for Rutherfurd’s wet-plate photographs of the sun and moon, made in 1865, Trouvelot’s drawings were considered the most accurate pictures of celestial objects available until the perfection of dry-plate photography.

Little is known about Trouvelot’s life before he came to America in 1857; there is no indication that he was especially interested in astronomy during his early years. Interested in silkworm culture, he thought the European gypsy moth, Porthetria dispar, might serve the same purpose. In 1869 he imported to Medford, Massachusetts, some live egg clusters for experimentation. Unfortunately, a few of the moths escaped, and after a decade began to proliferate alarmingly. This was the origin of the defoliation of trees in the northeastern United States.

A member of the Boston Natural History Society, Trouvelot presented papers on a variety of topics–mostly concerned with zoology – at society meetings. His earliest major contribution to astronomy, published in 1875 in Silliman’s Journal (now the American Journal of Science), was a paper on sunspots. Some one thousand of his sunspot drawings were deposited at the Harvard College Observatory. In 1881 Trouvelot was elected to the American Academy of Arts and Sciences.

In 1882 Trouvelot returned to France to join the staff of the new observatory at Meudon. While at Meudon he was particularly successful in his observations of solar prominences. In 1883 he went to the Caroline Islands to observe the total eclipse of the sun; he searched without avail for a supposed intra-Mercurial planet to account for the anomaly in the motion of Mercury.

Trouvelot published some fifty astronomical papers covering a wide range of topics, the most important being on the sun and Venus. He presented his last paper, concerning the transit of Mercury, on 12 November 1894 at the French Academy.

BIBLIOGRAPHY

I. Original Works. For reproductions of Trouvelot’s astronomical drawings, see The Trouvelot Astronomical Drawings Manual (New York, 1882); also see Annals of Harvard College Observatory, VIII, pt. 2 (1876), containing engravings prepared under the direction of Joseph Winlock. For references to Trouvelot’s published astronomical papers, see Poggendorff, III, 1368: IV, 1526.

II. Secondary Literature. Obituaries are contained in Nature, 52 (1895), 11; and Observatory, 18 (1895), 245–246. For mentions of Trouvelot’s work, see Edward H. Forbush and Charles H. Fernald, “The Gypsy Moth,” in Report. Massachusetts Department of Agriculture (1896); and Annals of Harvard College Observatory, 8 , pt.1 (1876), 53, 55, 64.

E. Dorrit Hoffleit