Mme. Lepaute: An Eighteenth Century Computer

Abstract

ELIZABETH CONNOR, Mount Wilson Observatory, Carnegie Institution of Washington, has written (Leaf. 189, Astro. Soc. Pac, Nov. 1944) a short account of the astronomical work of Mme. Lepaute, whom Lalande considered "the only woman in France who had genuine knowledge of astronomy". As a child she was a voracious reader, and it was generally recognized by those who met her that she had a brilliant mind. When Lalande and Lepaute, to whom Mme. Lepaute (née Nicole-Heine Étable de la Brière) was married in 1748, collaborated in a treatise on clock-making, Mme. Lepaute calculated a table for the book containing a number of oscillations for pendulums of different lengths and the lengths of pendulums corresponding to a given number of vibrations. Her great work was the assistance that she rendered in the computations of the perturbations of Halley's Comet, and Lalande pays her a tribute when he affirms that without her help Clairaut and he would scarcely have undertaken this enormous task. In 1759, Lalande was placed in charge of the Connaissance des Temps, and Mme. Lepaute became one of his assistants. When this work was given to someone else in 1774, they concentrated their attention on volume 7 of the "Ephémérides", and Mme. Lepaute made all the calculations for the sun, moon and planets for both volumes 7 and 8, covering the period 1774–93. In addition to this, she devoted much time to eclipses, computing a table of parallactic angles which was useful in eclipse work. She also made computations for the observation of the transit of Venus in 1761, and wrote a memoir on the subject for the Academy at Béziers. For twenty-five years she was engaged continuously in astronomical work; but her eyesight was finally affected and during the last years of her life she was unable to apply herself closely to the subject.