from the government of Earl Grey. On 21 Dec. 1835 he succeeded his father as second baronet. He took an active part, already a Conservative, as chairman of Sir Francis Burdett's committee in the famous Westminster election of 1837. At this time a writer in Blackwood characterised him as "one of the manliest and most uncompromising of the constitutional members of the House of Commons; a friend to the church, the king, and the people." He retired from Parliament in 1841. Sinclair was elected Rector of Marischal College (later Aberdeen University) for 1840–41. He was a faithful supporter of the anti-patronage society with reference to the church of Scotland and afterwards joined the free church. His last years were passed in seclusion at Thurso Castle or Torquay. He spent the winter of 1867 at Cannes, and, dying in Edinburgh on 23 October 1868, was buried at Harold's Tower, Thurso. Works Sinclair was a voluminous writer for the press and author of many pamphlets. His earliest work, Travels in Germany, in two volumes, describing his visits to the continent, was printed for private circulation. Only one copy is known to exist. Among his other publications were: Selections from the Correspondence carried on during recent Negotiations for the Adjustment of the Scottish Church Question, 8vo, Edinburgh, 1842. A Letter on the Church Question, 8vo, Edinburgh, 1843. Comme Charles X: an Essay on the Downfall of Louis-Philippe, 8vo, 1848. Observations on the new Scottish Poor Law, 8vo, Edinburgh, 1849. Letters to the Protestants of Scotland, 12mo, Edinburgh, 1852. Miscellaneous Thoughts on Popery, Prelacy, and Presbyterianism, 8vo, Edinburgh, 1853. Two Hundred Years of Popery in France, 12mo, Edinburgh, 1853. Popery in the First Century, 12mo, Edinburgh, 1855. Family Sinclair married, on 1 May 1816, Lady Catherine Camilla Manners (dau. of the 1st Lord Huntingtower), and with her had three sons and three daughters. He was succeeded in the baronetcy by his eldest surviving son, John George Tollemache Sinclair, M.P. for Caithness, 1869–85. His eldest son, Dudley Sinclair, was the director of the New Zealand Association, a colonisation and land company formed in New Zealand in 1937. In the late 1830s, Dudley invested in a logging and trading settlement at Cornwallis, New Zealand, hoping to remake the family fortune lost by John Sinclair by establishing a trading and shipping company on the Manukau Harbour. The settlement was mired with problems, unable to successfully log the