HEADQUARTERS SECOND AND TWELFTH CORPS,
Harper's Ferry, October 4, 1862.

I accidentally omitted to mention in my report of the battle of Antietam the names of Major F. N. Clarke, chief of artillery, and Surg. A. N. Dougherty, medical director, of my corps. These officers were both highly distinguished for their zeal and ability.

I would request that this note may be annexed to my report.

E. V. SUMNER,

Brevet Major-General, U. S. Army, Commanding.

General S. WILLIAMS.

Numbers 39. Report of Brigadier General Winfield S. Hancock, U. S. Army, commanding First Division, Second Army Corps, of the battle of Antietam.

HEADQUARTERS FIRST DIVISION, SECOND CORPS D'ARMEE,
Harper's Ferry, September 29, 1862.

COLONEL: In obedience to instructions from the major-general commanding the corps, I have the honor to submit a narrative of the operations of this (Richardson's) division during the battle of Antietam, and the time subsequent thereto, until the enemy had retreated from the field, Major-General Richardson's wound being of such a nature as to render it impracticable for him to make the report as to the period during which he exercised the command.

About 9.30 o'clock a. m. on the 17th instant, the division, commanded by General Richardson, crossed the Antietam at the ford constructed by our engineers; then moved forward on a line nearly parallel to the creek, and formed line of battle by brigades in a ravine behind the high ground overlooking Roulette's house, the Second Brigade, commanded by Brigadier-General Meagher, on the right, his regiments being placed in the following order from right to left: The Sixty-ninth New York Volunteers, commanded by Lieutenant Colonel James Kelly; the Twenty-ninth Massachusetts Volunteers, commanded by Lieutenant Colonel Barnes; the Sixty-third New York Volunteers, commanded by Colonel Burke, and the Eighty-eighth New York Volunteers, commanded by Lieutenant Colonel Patrick Kelly; the Third [First] Brigade, commanded by Brigadier-General Caldwell, on his left, and the brigade commanded by Colonel Brooke, of the Fifty-third Pennsylvania Volunteers, in the rear. Meagher's brigade immediately advanced, and soon became engaged with the enemy,k posted to the left and in front of Roulette's house. This brigade continued its advance under a heavy fire nearly to the crest of the hill overlooking Piper's house, the enemy being posted in strong force in a sunken road directly in its front.

A severe and well-sustained musketry contest then ensued, which, after continuing until the ammunition was nearly expended, this brigade, having suffered severely, losing many valuable officers and men, was, by direction of General Richardson, relieved by the brigade of General Caldwell, which until this time had remained in support. Caldwell's brigade advanced to within a short distance of the rear of Meagher's brigade. The latter then broke by companies to the rear, and the former by companies to the front, and in this manner passed their respective lines. Caldwell's brigade immediately advanced to the crest over-