# Gregory, Olinthus Gilbert (DNB00)

**GREGORY**, OLINTHUS GILBERT, LL.D. (1774–1841), mathematician, was born of humble parents at Yaxley, Huntingdonshire, on 29 Jan. 1774. He got his schooling in his native village, and at an early age was placed with Richard Weston, the Leicester botanist. Weston trained him in mathematics, with such good effect that at the age of nineteen he published (1793) a small volume of ‘lessons, astronomical and philosophical.’ Weston also introduced him as a contributor (1794) to the ‘Ladies' Diary.’ He drew up a treatise on the use
of the sliding rule; though not published, it brought him to the notice of Charles Hutton, LL.D. [q. v.], who became his correspondent and patron. About 1796 he settled in Cambridge, obtained a situation as sub-editor on the ‘Cambridge Intelligencer,’ under Benjamin Flower [q.v.], which he did not keep long, opened a bookseller's shop about 1798, and taught mathematics. His teaching became profitable, so he closed his shop and devoted himself to tutorial work. In 1802 he published a treatise on astronomy,
dedicated to Hutton, which brought him into notice.

He edited the ‘Gentleman's Diary’ for the Stationers' Company from 1802 to 1819, and the ‘Ladies' Diary’ from 1819 to 1840. In 1802 he became mathematical master at the Royal Military Academy, Woolwich, through the influence of Hutton. In 1804 or 1805 he obtained the degree of A.M. from Aberdeen. On Button's resignation (1807) he was appointed his successor in the mathematical chair at Woolwich. In 1808 he was made LL.D. of Aberdeen. His treatise (1806) on mechanics and his experiments (1823) to determine the velocity of sound were his most important contributions to physical science. He appeared also as a theologian in a work (1811) on Christian evidences and doctrines, which is included in Bonn's Standard Library. In preparing it he had an eye to the religious instruction of his children; his daughter (Mrs. Haddock) became an ardent Unitarian. Gregory was one of the projectors of the London University (now University College); his name was inscribed on the foundation-stone laid in Gower Street on 30 April 1827. He rendered further services to literature by his biographies of John Mason Good [q. v.] and Robert Hall (1764-1831) [q. v.] Gregory retired from his chair in 1838, but continued to live at Woolwich, where he died on 2 Feb. 1841. His son, Charles Hutton Gregory, is the eminent engineer. Of his separate publications, the following are the chief: 1. ‘Lessons, Astronomical and Philosophical,’ &c., 1793, 12mo; 4th edit, 1811, 12mo. 2. ‘A Treatise on Astronomy,’ &c., 1802, 8vo. 3. ‘A Treatise of Mechanics,’ &c., 1806, 8vo, 3 vols.; 2nd edit. 1807, 8vo. (The ‘Account of Steam Engines’ was separately reprinted, 1807 and 1809.) 4. ‘Letters … on the Evidences, Doctrines, and Duties of the Christian Religion,’ &c., 1811, 8vo, 2 vols.; 9th edit. 1857, 8vo, 1 vol. 5. ‘Elements of Plane and Spherical Trigonometry,’ &c., 1816, 12mo. 6. ‘Mathematics for Practical Men,’ &c., 1825, 8vo; 3rd edit. 1848, 8vo. 7. ‘Memoirs of … John Mason Good, M.D.,’ &c., 1828, 8vo. 8. ‘Memoir of the Rev. Robert Hall,’ &c., prefixed to ‘Works,’ 1832, 8vo; also separately, 1833, 8vo, and prefixed to ‘Miscellaneous Works,’ 1846, 8vo. 9. ‘Aids and Incentives to the Acquisition of Knowledge,’ London, 1838, a farewell address on resigning his chair. 10. ‘Hints to the Teachers of Mathematics,’ &c., 1840, 8vo; 3rd edit. 1848, 8vo. He translated René-Just Haüy's ‘Elementary Astronomy,’ 1807, 8vo, 2 vols.; contributed to, and partly edited, ‘The Pantologia,’ a dictionary of arts and sciences, completed 1813, 8vo, 12 vols.; was a contributor to ‘Nicholson's Journal’ between 1802 and 1813, and to a volume of ‘Dissertations’ on the trigonometrical survey,1815,8vo.

[Biog. Dict. of Living Authors, 1816, p. 137; Knight's Biography, 1866, iii. 193 sq.; Watt's Bibl. Brit.; private information.]