Sinclair, SIR JOHN, born at Thurso Castle, 10th May 1754, from Logan's tutorship passed to the High School of Edinburgh, and thence to the universities of that city, Glasgow, and Oxford. He was admitted a member of both the Scottish and English bars (1775-82), but, having in 1770 succeeded to the family estate, he devoted himself to his duties as a northern landlord, and to the more engrossing pursuits of public life. In 1780 he was returned to parliament for Caithness, in 1784 for Lostwithiel, and in 1796 for Petersfield, his parliamentary career extending till 1811. In 1784 he published a History of the Revenue of the British Empire; and in 1786 he was created a baronet. He travelled over Europe, gathering information on economical and commercial questions, and on his return set about establishing a society in Scotland for improving the breeds of sheep and the quality of wool. His exertions also led to the formation of the Board of Agriculture in 1793, of which he was president for thirteen years. This institution was the precursor of numerous agricultural associations, by which the country was greatly benefited. Sir John's most important undertaking was originating and carrying through the Statistical Account of Scotland (21 vols. 1791-99), comprising a description of every parish in Scotland. The parochial clergy were the chief contributors, but the indefatigable baronet also employed statistical missionaries, and was for seven years actively engaged in prosecuting the work. Sir John wrote on all manner of topics, including even a tragedy and treatises on health and longevity; and his publications during fifty years of ceaseless exertion are said to amount in number to 39 volumes and 367 pamphlets. Not one of the whole seems destined to live; their value perished in the using; but the long and active life of their author was highly beneficial to his country. He died at Edinburgh, 21st December 1835, aged eighty-one. See his Correspondence (2 vols. 1831) and Life (2 vols. 1837).
Sir John Sinclair left a numerous family, of whom the third son, JOHN (1797-1875), was archdeacon of Middlesex from 1842, and author of Sketches of Old Times (1875), &c.; whilst the fourth daughter, CATHERINE (1800-64), wrote a number of tales and descriptive works—Modern Accomplishments, Modern Society, Scotland and the Scotch, Shetland and the Shetlanders, &c.—all evincing literary taste and fine moral feeling.