Civil War Union Major General. He was born in Clinton, Connecticut, and attended the United States Military Academy at West Point, New York graduating 2nd in the class of 1841. He remained as an instructor at West Point for one year, then began a ten-year assignment in the Florida Keys where he undertook numerous engineering projects. At the outbreak of the Civil War he was stationed in Virginia at the Norfolk Navy Yard. When it became clear that Confederate troops would overrun the base, he was ordered to destroy the dry dock, he was captured by the advancing Confederates and help as a prisoner. He was released within a short period and was then ordered by the Army to go to Washington D.C. to assist in fortifying the city. He also served with Brigadier General Samuel P. Heintzelman's staff at First Bull Run. By August 1861 he was promoted to Major, and in September was made a Brigadier General. In November of that same year he distinguished himself as commander of the landing force which occupied Fort Walker near Hilton Head, South Carolina. He was promoted to Major General but the United States Senate later would revoked the promotion. He then commanded a division in John Sedgwick's VI Corps. He led the division in several engagements including Gettysburg and the Wilderness. He was promoted to Major General and given Corps command when Sedgwick was killed by a Confederate sharpshooter. He led the VI Corps at Cold Harbor and in the beginning phase of Petersburg. He returned to Washington later in the year, helping to repulse the attack by Jubal Early's forces in July of 1864. In October 1864, it was he who was in command of Union forces at Cedar Creek when Early's troops attacked. The battle forced Federals into retreat until General Philip Sheridan's recoupment of his scattered troops saved the day. After the war he was named Military Commander of Texas with the rank of Lieutenant Colonel until 1866, when he turned his attention to civil engineering. In 1879 he was promoted to Colonel, later that year he was named Chief of Army Engineers with the rank of Brigadier General. Included among his many engineering feats are the East River Bridge in New York City and the Sutro Tunnel in Nevada. Yet, his best known undertaking remains the completion of the Washington Monument. Its construction had stopped in progress because of the Civil War and a lack of funding. Under his direction, construction was resumed in 1880 and was completed in 1884, making it the tallest structure in the world. It would hold this distinction for one year until the Eiffel Tower was completed. 1884 also happened to be the very year he retired from the Army still holding the rank of Brigadier General. The obelisk marking his grave was erected as a memorial to him by the survivors of the VI Army Corps, Army of the Potomac.