No. 48. Report of Brigadier General Thomas Francis Meagher, U. S. Army, commanding Second Brigade, of the battle of Antietam.

HDQRS. (IRISH Brigadier) 2nd Brigadier, SUMNER'S CORPS,
HANCOCK'S DIVISION, ARMY OF THE POTOMAC,

In Camp on Bolivar Heights, Va., September 30, 1862.

CAPTAIN: I have the honor to submit the following statement of the part which the brigade under my command performed in the battle of the Antietam:

Being encamped 1 mile outside Frederick City, on this side, on the morning of the 14th of September the brigade received orders immediately to proceed to the support of General Hooker, who was at the time hotly engaged in the passes of the South Mountain with the enemy. Being halted for an hour or so, owing to the favorable reports from the headquarters of General Hooker, the brigade had an hour or so to take rest and refreshment, the first opportunity they and of doing so after a rapid and exhausting march over the rocky hills and through the tangled woods from their encampment outside Frederick City.

The Irish Brigade had the honor of leading the pursuit of the rebels from South Mountain through Boonsborough and Keedysville. Along this road and through these villages, in this pursuit, the brigade passed with the utmost alacrity and enthusiasm, Major-General Richardson, commanding the division, riding prominently at the head of the column and directing all its movements.

Early in the afternoon the enemy were discovered in full force, drawn up in line of battle on the heights near Sharpsburg and overlooking the Antietam. The brigade was halted and deployed in line of battle to the right and left of the Sharpsburg turnpike, the Eighty-eighth and Sixty-third Regiments New York Volunteers being on the left of the road and the Sixty-ninth New York Volunteers and the Twenty-ninth Massachusetts Volunteers being on the right.

Whilst in this position, though greatly protected by the hill on the slope of which they lay, the regiments forming the right of my command were constantly annoyed by the well directed artillery of the enemy. The Eighty-eighth and Sixty-third Regiments were also annoyed in a similar way, and the brigade lost several good men even in this comparatively safe position. In this position, however, we remained until the morning of the 17th, when, the men having breakfasted, a sudden order came for the brigade to fall in under arms, and take up the line of march, which Major-General Richardson would indicate. Filing by the right and proceeding at a rapid pace, the brigade crossed the ford of the Antietam a mile or so to the right of the bivouac of that morning, and as hastily, in compact order, following the lead of Major-General Richardson, who conducted the brigade to the field of battle, under cover of the rising ground and depressions which intervened between us and the enemy, we arrived at a corn-field, where Major-General Richardson ordered that everything but cartouch-boxes should be thrown off.

The men of the Irish Brigade instantly obeyed this order with a heartiness and enthusiasm which it was rare to expect from men who had been wearied and worn by the unremitting labors of a nine months' campaign.

Deploying from column into line of battle on the edge of this corn-field, they marched through it steadily and displayed themselves in