THORNTON, Seth Barton, soldier, born near Fredericksburg, Virginia, in 1814; died in San Augustin, Mexico, 18 June, 1847. He was educated at the common schools, was of an active and adventurous nature, and after a narrow escape from death by shipwreck was appointed in June, 1886, 2d lieutenant in the 2d United States dragoons, serving with credit in Florida against the Seminoles, becoming 1st lieutenant in 1837 and captain in 184i. In command of his squadron he exchanged the first shots with the enemy in the Mexican war at La Rosia, 25 April, 1846, and was severely wounded and captured with the greater part of his force after a gallant resistance by 40 dragoons against 500 lancers. At the close of General Winfield Scott's campaign, while at the head of his squadron in advance of Worth's division at the village of San Augustin, near the city of Mexico, Thornton was struck in the breast by a round shot and instantly killed.