Thomas Cochrane, 10th earl of Dundonald, (born December 14, 1775, Annesfield, Lanarkshire, Scotland—died October 31, 1860, London, England), iconoclastic British politician and admiral, who ranks among the greatest of British seamen.
He was the eldest son of the 9th earl, whose scientific experiments on his Scottish estates impoverished his family. In 1793 Thomas joined the ship commanded by his uncle, Alexander Cochrane, and thereafter served on other ships during the Napoleonic Wars. In 1806 and again in 1807 he was elected a member of Parliament.
In April 1809 Cochrane led a hazardous fireship attack on the French fleet in the Aix Roads in the Bay of Biscay, but the fruits of his courage were squandered when the commander in chief of the Channel Fleet, Adm. James Gambier, chose not to act upon the advantage that Cochrane had gained. Cochrane’s determined opposition to a proposed Parliamentary vote of thanks for Gambier for his actions at Aix Roads prompted Gambier to apply for a court-martial. In the event, Gambier was acquitted by a friendly court, largely as a result of Cochrane’s decision to allow the record—log books and fleet signal logs—to speak for itself rather than present charges against Gambier. The acquittal, in effect, left Cochrane culpable of having libeled Gambier. That situation, together with Cochrane’s unpopularity in government circles because of his demands for parliamentary and naval reform, resulted in his not being employed again at sea.