Cold Spring, New York, January 8, 1830. He made a specialty of topographical engineering, and was assistant professor of mathematics at West Point until the beginning of the Civil War, when he came into active service as lieutenant-colonel of the Fifth New York Volunteers. His promotion was rapid, and he reached the rank of major-general of volunteers in May, 1863. He served as brigade and division commander in the Fifth Army Corps, and in January, 1863, became chief topographical engineer, and, later, chief engineer of the Army of the Potomac. His service to the Union cause in defending Little Round Top at Gettysburg won him a brevet of colonel in the regular army. For a short time after Gettysburg he was in command of the Second Corps, and from March, 1864, to April, 1865, of the Fifth Corps, Army of the Potomac; after which he served for a short time in the Department of Mississippi. He left the volunteer service in May, 1865, having received the brevet of major-general in the regular army, in which he remained until February 13, 1866, when he resigned. His last years were spent on surveys and harbor improvements, and he died at Newport, Rhode Island, August 8, 1882.
Dover, Delaware, October 9, 1822, and served in the Mexican and Seminole wars. As major, he entered the Civil War, and was commissioned brigadier-general of volunteers in September, 1861. He led a division of the Fifth Army Corps and was commander for several short periods, notably at the battle of Gettysburg. His commission of major-general of volunteers was dated November 29, 1862. In SeptemberOctober, 1864, he was in command of the District of South Kansas. After leaving the volunteer service he was made colonel in the regular army, where he remained until he died in Brownsville, Texas, February 9, 1880.
Licking County, Ohio, in 1826, and served in the Mexican War and on the frontier. He was captain when the Civil War broke out, at the head of the Fifth Artillery. His battery fought with great bravery at Bull Run. As brigadier-general of volunteers, he had a brigade and then a division in the Fifth Army Corps, and took part in most of its important battles. He was given command of the corps on April 1, 1865, from which dated his appointment as major-general of volunteers. He led his corps in the final operations against Petersburg, and at Lee's surrender he received the arms and colors of the Army of Northern Virginia. He was one of the commission to carry out the terms of the surrender. After the close of the war, as colonel in the regular army, he was in command of the Department of Texas, where, during an outbreak of yellow fever, he refused to leave his post. Contracting the disease, he died in Galveston, September 15, 1867.