Organized at Auburn, N.Y., and mustered in September 8, 1862. Left State for Washington, D.C., September 12, 1862. Attached to 2nd Brigade, 1st Division, 12th Army Corps, Army of the Potomac, to October, 1862. 4th Brigade, 1st Division, 12th Army Corps, October, 1862, 2nd Brigade, Defenses north of the Potomac, Defenses of Washington, to December, 1862. Designation of Regiment changed to 9th New York Heavy Artillery December 9, 1862 (which see).