thematical master at King's College School, London; the latter post he held till his death. Among his pupils was Henry Fawcett [q. v.] He published several works on mechanics and pure mathematics, the chief of which are: 'Analytical Geometry' (a book which was afterwards greatly improved by J. R. Young), 'Treatise on Plane Trigonometry,' 'Spherical Trigonometry,' 'Examples of the Integral Calculus,' 'Examples of the Differential Calculus.' In applied mathematics he wrote 'Mathematics for Practical Men,' published 1833; 'The Theory of Bridges,' 1843; 'Treatise on the Steam Engine, with Practical Rules,' 1847; 'Principles and Practice of the Machinery of Locomotive Engines,' 1850. In 1841, with Olinthus Gregory [q. v.], he drew up and published 'Tables for the Use of Nautical Men.' He also contributed papers to the 'Diaries' and other mathematical periodicals. Hann was elected a member of the Institute of Civil Engineers in 1843, and was an honorary member of the Philosophical Society of Newcastle-on-Tyne. He died in King's College Hospital 17 Aug. 1856, aged 57 years. He married as a young man, and had several children.
[Latimer's Local Records of Newcastle, p. 384; Lady and Gentleman's Diary for 1857, p. 69; Proc. Inst. Civ. Engineers, vol. ii.(1843); Gent. Mag. 1856, pt. ii. pp. 513-15, 521; Ann. Register, August 1856.]
HANNA, SAMUEL, D.D. (1772?–1852), Irish presbyterian divine, was born at Kellswater, near Ballymena, co. Antrim, about 1772. He was educated at Glasgow, graduating M.A. in 1789. In 1790 he was licensed by Ballymena presbytery. He was ordained as minister of the presbyterian congregation of Drumbo, co. Down, on 4 Aug. 1795. His reputation as a preacher grew rapidly. On 11 Dec. 1799 he was installed as minister of Rosemary Street, Belfast. He revived the congregation, and his meeting-house was handsomely rebuilt (opened 15 April 1832). A warm advocate of Sunday schools and of bible distribution, he was also one of the first to interest Irish presbyterians in the subject of missionary enterprise. In 1816 the general synod resolved to provide a theological training for its students instead of sending them to Scotland. Hanna, in June 1817, was unanimously elected professor of divinity and church history, with an emolument of 36l. a year (he retained his congregation). His lectures were given at the Academical Institution, Belfast. In the following year he was made D.D. of Glasgow. In 1835 he obtained a coadjutor, Samuel Davidson, D.D., in the department of biblical criticism, and in 1837 was relieved of the departments of ecclesiastical history and pastoral theology by the appointment of James Seaton Reid, D.D., the historian. In 1840 Hanna was freed from active pastoral work by the election of William Gibson, D.D., as his assistant and successor at Rosemary Street. On 10 July 1840 he was chosen first moderator of the general assembly, formed at that date by the union of the general and secession synods. Hanna was a man of respectable powers, who worked hard for his church; without special ability as a theologian he left the impress of his own evangelical sentiments on a long succession of his pupils. He died at the residence of his son-in-law, Dr. Denham, at Derry, on 23 April 1852, in his eighty-first year. His portrait hangs in the hall of the Assembly's College, Belfast. William Hanna, D.D. (1880-1882) [q. v.], was his son. He published a few sermons and pamphlets, the earliest being his sermon as moderator of the general synod, Belfast, 1809, 8vo.
[Belfast News Letter, 30 April, 1852; Orthodox Presbyterian, May 1832, p. 288; Reid's Hist. Presb. Church in Ireland (Killen), 1867, iii. 415 sq.; Killen's Hist. Cong. Presb. Church in Ireland, 1886, pp. 63 sq., 1-26, 258 sq.]
HANNA, WILLIAM, LL.D., D.D. (1808–1882), theological writer, born at Belfast on 26 Nov. 1808, was the son of the Rev. Dr. Samuel Hanna [q. v.], a distinguished minister of the presbyterian church of Ireland in that town. He received his university education at Glasgow, where he distinguished himself as a student, especially in the classes of mathematics and natural philosophy. From Glasgow he proceeded to the divinity classes in the university of Edinburgh, and studied under Dr. Thomas Chalmers [q. v.] Here likewise his high ability showed itself, particularly in the debating societies.
In 1834 he was licensed as a probationer of the church of Scotland, and in the following year he was ordained to East Kilbride, a parish near Glasgow, 17 Sept. 1835. While here he married Anne, eldest daughter of Dr. Chalmers. In 1837 he was translated to the parish of Skirling, Peebles-shire, in the immediate neighbourhood of Biggar. During the controversy that preceded the disruption of the church in 1843, he took an active part on the side of Chalmers and his friends. When the disruption took place he left the establishment, taking his whole congregation with him. On the death of Dr. Chalmers in 1847 Hanna was entrusted with the writing of his life. In order to obtain the requisite leisure, he arranged a temporary
