HORROCKS, JEREMIAH (1619-1641), English astron omer, was born in 1619 at Toxteth Park, near Liverpool. He was a student at Emmanuel college, Cambridge, from 1832-35; then he became a tutor at Toxteth and studied astronomy in his spare time. He calculated that, contrary to the prediction in Kepler's Rudolphine Tables, a transit of Venus would occur on Nov. 24 (0.S.) 1639. This was a Sunday, and Horrocks, acting at that time as curate of Hoole, rushed from his clerical duties just in time to see the transit take place. This was the first transit of Venus to be observed. Horrocks was a brilliant young man, and before his death on Jan. 3, 1641, when in his 22nd year, he had considerably advanced the lunar theory; reduced the solar parallax to 14"; suggested perturbations of the moon's orbit as due to the disturbing action of the sun ; made observations of the tides; and investigated the irregularities of motion of Jupiter and Saturn.
Only a remnant of the papers left by Horrocks was preserved by the care of William Crabtree. After his death (which occurred soon after that of his friend) these were purchased by Dr. Worthington, of Cam bridge ; and from his hands the treatise Venus in sole visa passed into those of Hevelius, and was published by him in 1662 with his own observations on a transit of Mercury. The remaining fragments were, under the direction of the Royal Society, edited by Dr. Wallis as Astronomia Kepleriana defensa et promota, and published with numer ous extracts from the letters of Horrocks to Crabtree, and a sketch of the author's life, in a volume entitled Jeremiae Horroccii opera post huma (London, 1672). A memoir of his life by the Rev. Arundell Blount Whatton, prefixed to a translation of the Venus in sole visa, appeared at London in 5859.
See also J. Hevelius, Mercurius in sole visus (1662) ; Sir E. Sher burne, Sphere of M. Manilius (1675) ; T. Birch, History of the Royal Society (4 vols., ; B. Martin, Biographia philosophica (1764) ; J. B. J. Delambre, Histoire de l'astronomie moderne (2 vols., 1821) ; and Histoire de l'astronomie au XVIIIe siecle (5827) ; W. Whewell, History of the Inductive Sciences (3 vols., 1837) ; S. Rigaud, Corre spondence of Scientific Men (2 vols., 1841-62) ; R. Grant, History of Physical Astronomy (1852) ; R. Brickel, Transits of Venus, 1639-1874 (Preston, 1874) ; J. E. Bailey, "The Writings of J. Horrocks and W. Crabtree" in the Palatine Note-Book (with bibliography, 5883, also in Notes and Queries, Dec. 2, 1882). See also Notes and Queries, 3rd series, vol. v. (1864) , 5th series, vols. ii. and iv. (1874).