Dictionary of National Biography, 1885-1900/Bancroft, Edward (1744-1821)
BANCROFT, EDWARD, M.D., F.R.S. (1744–1821), politician, naturalist, and chemist, was born at Westfield, Massachusetts, on 9 Jan. 1744. He received only a rudimentary education, and after a few years' apprenticeship to some trade, he ran away to sea. In 1763 he settled in Guiana, where he commenced to practise medicine. He then removed to England, where in 1769 he published 'An Essay on the Natural History of [Dutch] Guiana … with an account of the Religion, Manners, and Customs of several Tribes of its Indian Inhabitants' (London, 8vo). Bancroft had by this time become a freethinker, and in 1770 he published a novel, 'Charles Wentworth,' of which the motive is said to have been as attack on the Christian religion (there is no copy in the British Museum Library).
Meanwhile, in 1769, Bancroft published, in answer to William Knox (1732-1810) [q. v.] and George Grenville, his 'Remarks on the Review of the Controversy between Great Britain and her Colonies' (London, 8vo). Possibly it was this work that brought him the acquaintance of Benjamin Franklin and Joseph Priestley, who secured him employment on the 'Monthly Review.' He was elected fellow of the Royal Society on 20 May 1778, being then described as M.B.; he afterwards became M.D., though of what university is not known (Thomson, Royal Soc. App. p. liv). When the breach with the American colonies became complete, Bancroft seems to have acted as a spy in London for Franklin, who removed to Passy. In 1777 he was suspected of complicity in the attempt to burn Portsmouth dockyard, but he escaped to France (cf. Franklin, Memoirs, 1861, i. 315). There he proceeded to turn king's evidence, and forwarded to the British government information communicated to him by Silas Deane, one of the American commissioners in Europe.
After the close of the war Bancroft became principally concerned in dyeing and calico printing, in which he made important discoveries. In 1786 an act of parliament secured him special rights of importing and using a certain kind of oak bark in calico-printing, but in 1799 a bill which had passed the House of Commons, for extending his rights for seven years, failed to pass the Lords, in consequence of the opposition of many northern calico-printers. Bancroft was bitterly disappointed, as he considered be had exercised his rights liberally; and in less than twelve months the bark in question rose to three times the price at which Bancroft had invariably supplied it, and at which, by the proposed bill, he would have been bound to supply it for seven years more. In 1794 he published 'Experimental Researches concerning the Philosophy of Permanent Colours.' The first volume was remodelled and a second added in 1813. The work contains a valuable account and discussion of the theory of colours and the methods of fixing them.
Bancroft died at Margate on 8 Sept. 1821 (Gent. Mag. 1821, ii. 879). He was married and Edward Nathaniel Bancroft [q.v.] was his son.
Bancroft's Works in Brit. Mus. Libr.; Biogr. Dict. of Living Authors, 1816; Priestley's Works, xix. 293, Letters, ed. Rutt, ii. 63, 65, 66.]