"Henry Larcom Abbot (August 13, 1831 – October 1, 1927) was a military engineer and career officer in the United States Army. He served in the Union Army during the American Civil War and was appointed brevet brigadier general of volunteers for his contributions in engineering and artillery. In 1866 he received additional brevet appointments as major general of volunteers and brigadier general in the Regular Army. He conducted several scientific studies of the Mississippi River with captain, later Major General Andrew A. Humphreys. After his retirement, Abbot served as a consultant for the locks on the Panama Canal. He was elected a Fellow of the American Academy of Arts and Sciences in 1863. At the outbreak of the Civil War, Abbot was assigned to Brigadier General Irvin McDowell's forces and was wounded at the First Battle of Bull Run. He later became a topographical engineer in the Army of the Potomac during the Peninsula Campaign and aide-de-camp to Brig. Gen. Andrew Humphreys. During this campaign he was brevetted major for his service at the siege of Yorktown. On July 18, 1862, Abbot was promoted to captain in the Regular Army and was assigned to the staff of Brig. Gen. John G. Barnard until November 11, 1862. He was then briefly assigned as a Topographical Engineer in the Department of the Gulf. On January 19, 1863 he was appointed colonel of the 1st Connecticut Heavy Artillery but on March 3, 1863 was transferred to the Washington Defenses where he commanded a brigade.In May 1864 he was transferred to command the Artillery during the siege of Petersburg. On December 12, 1864, President Abraham Lincoln nominated Abbot for appointment to the grade of brevet brigadier general of volunteers to rank from August 1, 1864 and the U.S. Senate confirmed the appointment on February 20, 1865. In December 1864 he was placed in command of all siege artillery in the Army of the Potomac and Army of the James that were besieging Petersburg. In January 1865 General Alfred H. Terry requested General Abbot accompany his expeditionary force to Fort Fisher. Abbot commanded a provisional brigade of siege artillery during the successful Second Battle of Fort Fisher.Abbot was mustered out of the volunteer service on September 25, 1865. On January 13, 1866, President Andrew Johnson nominated Abbot for appointment to the grade of brevet major general of volunteers to rank from March 13, 1865 and the U.S. Senate confirmed the appointment on March 12, 1865. On July 17, 1866, President Johnson nominated Abbot for appointment to the grade of brevet brigadier general in the regular army to rank from March 13, 1865 and the U.S. Senate confirmed the appointment on July 23, 1865."