LACAILLE, Nicolas Louis de (1713-1762), a zealous and successful astronomer, was born at Rumigny, near Rheims, March 15, 1713. Left destitute by the death of his father, who held a post in the household of the duchess of Vendôme, his theological studies at the Collége de Lisieux in Paris were prosecuted at the expense of the duke of Bourbon. After he had taken deacon’s orders, however, he devoted himself exclusively to science, and, through the patronage of Cassini, obtained employment, first in surveying the coast from Nantes to Bayonne, then, in 1739, in remeasuring the French arc of the meridian. The success of this difficult operation, which occupied two years, and achieved the correction of the anomalous result obtained by the elder Cassini in 1684, was mainly due to Lacaille’s industry and skill. He was rewarded by admission to the Academy, and the appointment of mathematical professor in Mazarin college, where he worked diligently for some years in a small observatory fitted up for his use. His desire to observe the southern heavens led him to propose, in 1750, an astronomical expedition to the Cape of Good Hope, which was officially sanctioned, and fortunately executed (see Astronomy, vol. ii. p. 757). On his return in 1754 he was distressed to find himself an object of public attention, and withdrew to his former retreat in Mazarin college, where he died, March 21, 1762, of an attack of gout aggravated by unremitting toil. Lalande said of him that, during a comparatively short life, he had made more observations and calculations than all the astronomers of his time put together. And, his carefulness equalling his rapidity, the quality of his work rivalled its quantity. The rectitude of his moral character earned him universal respect, and his career ...