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 on 23 March 1829. Acting under the advice of Mr. J. R. Hind, foreign secretary of the Royal Astronomical Society, Pogson, in 1847, at the age of eighteen, calculated the orbits of two comets. During the three following years several other comets and the recently discovered minor planet Iris, claimed his attention. This led to his appointment as an assistant at the South Villa Observatory, London. After a short stay there he obtained the post of assistant at the Radcliffe Observatory, Oxford, in 1852, and it was here that he began his course of discoveries, which soon made him known as a first-class observer. While at Oxford, between 1856 and 1857, he discovered four minor planets: Amphitrite, 2 March 1854; Isis, 23 May 1856; Ariadne, 15 April 1857; Hestia, 16 Aug. 1857. For the discovery of Isis he was awarded the Lalande medal of the French Academy.

Much of his time at Oxford was devoted to variable stars, but the archives of the Radcliffe Observatory between 1852 and 1858 show that the more ordinary work was in no way neglected. In 1854 he assisted at the famous experiments for determining the mean density of the earth, conducted by Sir George Airy, the astronomer-royal at the Harton Colliery. Airy accorded him his hearty thanks, and remained his cordial friend through life.

In 1859 Pogson was appointed director of the Hartwell Observatory belonging to (1783–1866) [q. v.] There his time was spent in the study of variable and double stars, the search for asteroids, and the formation of star charts. During the two years he remained at Hartwell the ‘Monthly Notices of the Royal Astronomical Society’ for 1859–1860 contain fourteen papers from his pen regarding variable stars and minor planets, while he communicated several papers to the British Association, and made some valuable contributions to the ‘Speculum Hartwellianum.’ In October 1860 he was appointed by Sir Charles Wood, secretary of state for India, government astronomer at Madras. Sir John Herschel wrote at this time of his ‘conspicuous zeal, devotion to and great success in the science of astronomy;’ and C. Piazzi Smyth bore testimony to his ‘unwearied diligence, enthusiastic zeal, and signal success.’

Pogson reached Madras early in 1861, full of high hopes as to the work he would accomplish. He soon discovered another minor planet, which he named Asia, as being the first discovered by an observer in that continent. Between 1861 and 1868 he discovered no less than five minor planets, and seven variable stars were added to his list of discoveries between 1862 and 1865, and an eighth in 1877. The chief work carried on by Pogson at the Madras Observatory was twofold: first, the preparation of a star catalogue, for which 51,101 observations were made between 1862 and 1887; secondly, the formation of a variable star atlas, begun at Oxford in 1853, and carried on with remarkable perseverance. The catalogues, which were to accompany the atlas, contained the positions of upwards of sixty thousand stars, observed entirely by Pogson himself. Unhappily they are still unpublished. Pogson observed the total eclipse of the sun on 18 Aug. 1868 at Masulipatam, and was the first to observe the bright line spectrum of the Corona.

He remained for thirty years government astronomer at Madras and, during the whole of that time he took no leave. His devotion to his science and his anxiety to publish his works induced him to remain so long that his health at last failed, and he died at his post in June 1891 in his sixty-third year. He was a fellow of the Royal Astronomical Society, and the Indian government nominated him a companion of the Indian Empire.

Pogson's chief interest as an astronomer lay in observations with the equatoreal and meridian circle, and in the use of these instruments he had few equals. As an observer only one or two contemporaries could equal him. In all, he discovered nine minor planets between the orbits of Mars and Jupiter, and twenty-one new variable stars. He had an exhaustive knowledge of the literature of his subject.

His first wife, whom he married in 1849 at the early age of twenty, was Elizabeth Ambrose, who died in 1869, leaving a large family. On 25 Oct. 1883 he married Edith Louisa Stopford, daughter of Lieutenant-colonel Charles W. Sibley of the 64th regiment, and by her had three children, one of whom died in infancy.



POINGDESTRE, JEAN (1609–1691), writer on the laws and history of Jersey, born in the parish of St. Saviour in the island of Jersey, and baptised on 16 April 1609, was the eldest son of Edward Poingdestre, by his second wife, Pauline Ahier. He was among the first to obtain one of the scholarships founded at Oxford by Charles I on behalf of Jersey students, and in 1636 was elected a fellow of Exeter College, Oxford. He was always considered an accomplished classical scholar, and held the fellowship till 1648, when he was ejected by the parliamentary party.