arms of Smyth in addition to his own. After studying for six years at Edinburgh University, he graduated as M.D. in 1764, taking for his thesis ‘De Paralysi,’ and introducing into it a short history of medical electricity. He then visited France, Italy, and Holland. In 1768 he settled in London, and received the appointment of physician to the Middlesex Hospital. He engaged in experiments with nitrous-acid gas for prevention of contagion in cases of fever, these experiments being continued at the request of the government on board the Spanish prison-ship at Winchester, where an epidemic prevailed. In 1802, for his services in this respect, parliament voted him a reward of 5,000l. His claim to the merit of the discovery was disputed by Dr. James Johnstone of Kidderminster, for his father, and by M. Chaptal, a Frenchman, for Guyton-Morveau; but, after a keen controversy, Smyth's claims were upheld. He subsequently went to the south of France for his health, and on his return settled at Sunbury. He was elected fellow of the Royal Society in May 1779 (Thomson, Hist. of Royal Soc. App. p. lvii), and was also a fellow of the Royal College of Physicians, and physician-extraordinary to George III. He died on 18 June 1821. In 1775 he married Mary, only child and heiress of Thomas Holyland of Bromley, Kent, and had by her eight sons and two daughters. His eldest son was General Sir James Carmichael Smyth (1779–1838) [q. v.] His eldest daughter, Maria, married, in 1800, Dr. Alexander Monro ‘tertius’ [q. v.]
Smyth was the author of a large number of medical treatises illustrative of his experiments. Among them were: 1. ‘An Account of the Effects of Swinging, employed as a remedy in Pulmonary Consumption,’ London, 1787, 8vo. 2. ‘A Description of the Jail Distemper, as it appeared among the Spanish Prisoners at Winchester in 1780,’ London, 1795, 8vo. 3. ‘An Account of the Experiments made on board the Union Hospital Ship to determine the Effect of the Nitrous Acid in destroying Contagion,’ London, 1796, 8vo. 4. ‘The Effect of the Nitrous Vapour in preventing and destroying Contagion,’ London, 1799, 8vo. 5. ‘Letter to William Wilberforce’ [on Dr. Johnstone's claim], 1805, London, 8vo. 6. ‘Remarks on a Report of M. Chaptal,’ 1805, London, 8vo. 7. ‘A Treatise on Hydrocephalus,’ 1814, London, 8vo. Smyth also edited the ‘Works of the late Dr. William Stark,’ 1788, London, 4to.
[Gent. Mag. 1821, ii. 88–9; Anderson's Scottish Nation.]
SMYTH, Sir JAMES CARMICHAEL, baronet (1779–1838), military engineer, and governor of British Guiana, eldest son of James Carmichael Smyth [q. v.], was born in London on 22 Feb. 1779. He was educated at the Charterhouse school, and entered the Royal Military Academy at Woolwich on 1 March 1793. He received a commission as second lieutenant in the royal artillery on 20 Nov. 1794, and was transferred to the royal engineers on 13 March 1795.
In May 1795 Smyth was sent to Portsmouth, and in April of the following year to the Cape of Good Hope, where he arrived in June. He served under Generals Craig and Doyle in the operations that year against the Dutch. He was promoted to be lieutenant on 3 March 1797. He took part under Generals Dundas and Vandeleur in the operations 1798 to 1800. After a visit to England, 1800–1, he was promoted to be second captain on 1 July 1802. On the restoration of Cape Colony to the Dutch in 1803, Smyth returned to England. In October 1805 he joined Sir David Baird's expedition to the Cape of Good Hope as commanding royal engineer. He arrived on 4 Jan. 1806. At Smyth's suggestion a landing was effected on the beach near Blaauwberg on the 7th. Smyth was detached on board the sloop Espoir to Saldanha Bay, and was, to Baird's regret, absent from the battle of Blaauwberg (8 Jan.). On the surrender of Capetown, Baird appointed Smyth acting colonial secretary in addition to his military duties. He was promoted to be first captain on 1 July 1806, and was employed in strengthening and repairing the defences of Table Bay and Simon's Bay. He relinquished the appointment of colonial secretary on the arrival in May 1807 of the Earl of Caledon as governor with a complete staff, and returned to England in September 1808. In the following winter he was with Sir John Moore at Coruña, returning with the remnant of the army to England in February. In April he constructed Leith Fort, and on 20 Oct. 1813 was promoted lieutenant-colonel.
In December of the same year he joined the expedition to Holland under his relative, General Sir Thomas Graham (afterwards Lord Lynedoch) [q. v.], as commanding royal engineer. He landed the same month with Graham at Zeyrick Zee, and head-quarters were established at Tolen. He was engaged in the action of Merxem on 13 Jan. 1814, and the subsequent bombardment of Antwerp early in February. Having carefully reconnoitred the fortress of Bergen-op-Zoom, Smyth advised its assault, which