Born in London, August, 1833; d. 27 Dec. 1889. He belonged to a well-known Catholic family. His schooling was first at Gifford Hall, and then at the Benedictine College, Douai, where he proceeded to Rome to study for the priesthood. Having resolved to enter the Society of Jesus, he entered the novitiate (1853-5) first at Hodder, and then at Beaumont Lodge, after which he pursued his studies at St. Acheul, near Amiens, and at Stonyhurst. In consequence of his marked bent for mathematics, he was sent to attend the lectures of professor De Morgan, in London, and those of Bertrand, Lionville, Delaunay, Cauchy, and Serret, in Paris. In the autumn of 1860 he was recalled to Stonyhurst to teach physics and mathematics, likewise taking charge of the observatory.

In 1863 he commenced his theological studies at St. Beuno's, N. Wales, and was ordained in 1866. He resumed his former duties at Stonyhurst, which during the rest of his life were uninterrupted, save by special scientific engagements. In company with Father Walter Sidgreaves, he made magnetic surveys, in 1868, of Western, in 1869 of Eastern, France, and in 1871 of Belgium. In 1870 he went in charge of a government expedition to observe a solar eclipse at Cadiz; at Carriacou (West Indies) in 1886; in Moscow in 1887; and at the Salut islands in 1889, on which journey he lost his life.

In 1874 he headed a party similarly sent to Kerguelen in the South Indian Ocean, to observe a transit of Venus, when he also took a series of observations to determine the absolute longitude of the place, and others for the magnetic elements, not only at Kerguelen itself, but, on his way to and fro, at the Cape, Bombay, Aden, Port Said, Malta, Palermo, Rome, Naples, Florence, and Moncalieri. He likewise drew up a Blue-book on the climate of "The Isle of Desolation", as Kerguelen was called by Captain Cook.

In 1882 he went again with W. Sidgreaves, to observe a similar transit in Madagascar, and he again took advantage of the occasion for magnetic purposes. In 1874 he became a Fellow of the Royal Society.

At Stonyhurst, while he greatly developed the meteorological work of the observatory, and in the province of astronomy made frequent observations of Jupiter's satellites, of stellar occultations, of comets, and of meteorites, it was in the department of solar physics that he specially laboured, particular attention being paid to spots and faculæ. For observation in illustration of these an ingenious method was devised and patiently pursued. Father Perry was moreover, much in request as a lecturer. He died while actually performing the duty assigned to him in conducting an eclipse expedition in the pestilential group misnamed the "Isles de Salut". The observation on this occasion was exceedingly successful, and Father Perry, though already severely indisposed, managed to perform his part without interruption. As soon as it was over, however, he became alarmingly worse, and having gotten on board the H.M.S. "Comus", which had been detained for the service, he died at sea five days later, 27 Dec., 1889. He was buried in the Catholic cemetery at Georgetown, Demerara. An account of his life and scientific works by CORTIE is published by the CATHOLIC TRUTH SOCIETY.

John Gerard.