No. 52. Report of Colonel John R. Brooke, Fifty-third Pennsylvania Infantry, commanding Third Brigade, of the battle of Antietam.

HDQRS. THIRD BRIGADE, RICHARDSON'S DIVISION,
On the Battle-field near Sharpsburg, Md., September 19, 1862.

SIR: On the morning of the 17th instant this brigade received orders to march. In a few moments we were on our way to the field of battle. Crossing the Antietam, we marched rapidly to the support of French, who was being hard pressed, and formed line of battle in a small valley in rear of Meagher's Irish Brigade, which pressed forward at once and soon became engaged. General Richardson then ordered me to move forward, which was done with great precision under a terrific fire of shot and shell. Caldwell's brigade having relieved the Irish Brigade on the front by a flank movement from the left, I here ordered the men to lie down. At this time the enemy charged and drove back the troops on our right, when the Fifty second New York and the Second Delaware, under Colonel Frank, changed front to meet this attack, and, by direction of General Richardson, I led the Fifty-seventh and Sixty-sixth New York and Fifty-third Pennsylvania to the right, to check any attempt the enemy might make to reach our rear.

The enemy having taken post in a corn-field in rear of Roulette's farm-house, I sent the Fifty-third Pennsylvania to dislodge them and hold the position, which was done with great gallantry. I then advanced the Fifty-seventh and Sixty-sixth New York to relieve Caldwell's lines, which were now fiercely assailed by fresh troops of the enemy. Passing his line with steadiness and regularity, the two gallant regiments, Fifty-seventh and Sixty-sixth New York, drove the enemy from the field in great confusion, capturing two colors and covering the ground with dead and wounded. It was here the gallant Lieutenant Colonel Parisen fell while bravely cheering on his men to victory.

Finding that the enemy made no attempt to regain the field, I sought for and obtained the permission of General Richardson to withdraw my line from the now untenable position, being exposed to a cross-fire of the enemy's batteries. Taking post under the crest of the hill on the right of the battery, and throwing skirmishers to the front, I caused the ammunition to be replenished. It was at this time that the general commanding was dangerously wounded, while directing the fire of a battery on the left.

In a short time General Hancock arrived and took command. Nothing now occurred except an occasional interchange of shots on the line of pickets. It gives me pleasure to say that every man did his duty unflinchingly. About 2,000 stand of arms were captured, as also a great number of prisoners, who were sent through the ranks to the rear.

Of my staff, Lieutenant Charles P. Hatch, acting assistant-adjutant general, did his duty bravely and well. Lieutenant John T. Potts, aide-de-camp, was wounded in the thigh while in the performance of his duty. Lieutenant J. M. Faville, adjutant Fifty-seventh New York Volunteers, after Lieutenant Potts was borne from the field, supplied his place with great gallantry. I would also mention the brave chaplain of the Sixty-sixth New York Volunteers, Mr. Dwight, who was constantly upon the field