MASKELYNE, NEVIL English astronomer royal, was born in London, on Oct. 6, 1732. He was educated at Westminster school and Trinity college, Cambridge, where he graduated as seventh wrangler in 1754. He was ordained in 1755, but his interest in astronomy had been aroused by the eclipse of July 25, 1748, and in 1761, on Bradley's recommenda tion, he was deputed by the Royal Society to observe the transit of Venus in St. Helena. During the voyage he experimented upon the determination of longitude by the method of "lunars," and introduced this method into navigation by publishing in 1763 the British Mariner's Guide. In 1765 he succeeded Bliss as astronomer royal. Maskelyne's chief aim was the practical im provement of the art of navigation and in 1766 he published the first volume of the Nautical Almanac. He continued the superin tendence of this, his greatest work, until his death on Feb. 9, 181t.
Maskelyne's first contribution to astronomical literature was "A Proposal for Discovering the Annual Parallax of Sirius," published in 1760 (Phil. Trans., li. 889). Subsequent volumes of the same series contained his observations of the transits of Venus (1761 and 1769), on the tides at St. Helena (1762), and on various astronomical phenomena at St. Helena (1764), and at Barbados (1764). In 1772 he suggested to the Royal Society the famous Schehallion experiment for the determination of the earth's density and carried out his plan in 1774 (Phil. Trans., 1. 495). From Maskelyne's observations Chas. Hutton deduced a density for the earth 4.5 times that of water (Ib. lxviii. 782).
See The Royal Observatory, Greenwich (r9oo), which gives an account of his life and work.