THOM, George (tom), soldier, born in Derry, New Hampshire, 21 February, 1819. He was graduated at the United States military academy in 1839, assigned to the topographical engineers, and became 2d lieutenant in 1840. He served in connection with the survey of the boundary between the United States and the British provinces under the treaty of Washington, in 1842-'7 and on the staff of General Franklin Pierce in the war with Mexico. He became 1st lieutenant in 1849, and captain for fourteen years' service in July, 1853. In 1853-'6 he served in connection with the survey of the boundary between the United States and Mexico. At the opening of the civil war he was a major, but was appointed colonel and additional aide-de-camp in November, 1861. Colonel Thorn was continuously employed on engineer and other duty on the staff of General Henry W. Halleck till April, 1865, being present during the siege of Corinth. He was also present at the battle of Cedar Creek, Virginia He was promoted lieutenant-colonel of engineers in 1866, and was thereafter in charge of river and harbor improvements in the New England states till 20 February, 1883, when, having been forty years in service, he was, at his own request, retired from active service. He became colonel of engineers in 1880, and was brevetted brigadier-general United States army, " for faithful and meritorious services during the rebellion."