1911 Encyclopædia Britannica/Bradley, James

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BRADLEY, JAMES (1693–1762), English astronomer, was born at Sherborne in Gloucestershire in March 1693. He entered Balliol College, Oxford, on the 15th of March 1711, and took degrees of B.A. and M.A. in 1714 and 1717 respectively. His early observations were made at the rectory of Wanstead in Essex, under the tutelage of his uncle, the Rev. James Pound (1669–1724), himself a skilled astronomer, and he was elected a fellow of the Royal Society on the 6th of November 1718. He took orders on his presentation to the vicarage of Bridstow in the following year, and a small sinecure living in Wales was besides procured for him by his friend Samuel Molyneux (1689–1728). He, however, resigned his ecclesiastical preferments in 1721, on his appointment to the Savilian professorship of astronomy at Oxford, while as reader on experimental philosophy (1729–1760) he delivered 79 courses of lectures in the Ashmolean museum. His memorable discovery of the aberration of light (see Aberration) was communicated to the Royal Society in January 1729 (Phil. Trans. xxxv. 637). The observations upon which it was founded were made at Molyneux’s house on Kew Green. He refrained from announcing the supplementary detection of nutation (q.v.) until the 14th of February 1748 (Phil. Trans. xlv. 1), when he had tested its reality by minute observations during an entire revolution (18.6 years) of the moon’s nodes. He had meantime (in 1742) been appointed to succeed Edmund Halley as astronomer royal; his enhanced reputation enabled him to apply successfully for an instrumental outfit at a cost of £1000; and with an 8-foot quadrant completed for him in 1750 by John Bird (1700–1776), he accumulated at Greenwich in ten years materials of inestimable value for the reform of astronomy. A crown pension of £250 a year was conferred upon him in 1752. He retired in broken health, nine years later, to Chalford in Gloucestershire, and there died on the 13th of July 1762. The printing of his observations was delayed by disputes about their ownership; but they were finally issued from the Clarendon Press, Oxford, in two folio volumes (1798, 1805). The insight and industry of F. W. Bessel were, however, needed for the development of their fundamental importance.

Rigaud’s Memoir prefixed to Miscellaneous Works and Correspondence of James Bradley, D.D. (Oxford, 1832), is practically exhaustive. Other sources of information are: New and General Biographical Dictionary, xii. 54 (1767); Biog. Brit. (Kippis); Fouchy’s “Éloge,” Paris Memoirs (1762), p. 231 (Histoire); Delambre’s Hist. de l’astronomie au 18me siècle, p. 413.