The regiment was on picket duty from the evening of the 16th to the 17th. On the following morning I received orders to march. Made a short a much, and camped near a ford on the Potomac River. On the 20th, as soon as all the regiment had crossed the river, I followed after the Second and Tenth U. S. Infantry, then a short distance ahead. About a mile from the ford, Major C. S. Lovell, of the Tenth U. S. Infantry, commanding the Second Brigade, gave the command to halt and load. This being done, the brigade was formed in line of battle in the wood, the right resting on the road. We remained in this position for about thirty minutes, when I received an order to fall back in line to the brow of the hills near the river. After taking this position in line, I ordered a company to cover the front of the regiment as skirmishers. While acting thus, the enemy's pickets were advancing very fast, supported by a battery, cavalry, and a large force of infantry. This fact being known to the commanding officer of the brigade, I soon after received an order through his adjutant to fall back across the river,which was done in good order. The casualties between these periods were 2 men wounded.

Very respectfully, your obedient servant,

LEVI C. BOOTES,

Captain Sixth Infantry, Commanding Regiment.

ACTING ASSISTANT ADJUTANT-GENERAL,

Headquarters Second Brigade, Sykes' Division.

No. 105. Report of Major De L. Floyd-Jones, Eleventh U. S. Infantry, of the battle of Antietam and action near Shepherdstown.

HEADQUARTERS ELEVENTH INFANTRY, Camp near Sharpsburg, Md., September 24, 1862.

SIR: In accordance with instructions from brigade headquarters, I beg to submit the following report of the movements and casualties of the regiment from the 16th instant up to the present time:

The regiment moved from camp near Middletown Heights on the morning of the 16th instant, crossed Middletown Heights, and in the evening camped near Sharpsburg; distance marched, about 8 miles.

On the 17th instant remained in the same position. Private Patrick Clark, of Company G, was struck in the head by a spent grape-shot and wounded slightly. On the 18th remained in the same place without meeting with any casualties. On the morning of the 19th moved forward about 3 miles in the direction of Shepherdstown, and encamped about half a mile from the Potomac River.

On the 20th instant we crossed the Potomac near Shepherdstown, and, after advancing a short distance into the country, Company D was ordered to advance as skirmishers, under command of Lieutenant George E. Head. They advanced to the edge of the woods and discovered the enemy in large force moving toward us. We were then ordered to fall back, within we did in good order, the skirmishers of the enemy keeping up a brisk fire during the movements. We halted on a hill close to the river, and replied to the fire of the enemy for some minutes with good effect. At this time Private John J. Boddy, of Company E, was wounded slightly; Private V. S. Wheeler, of Company B, wounded in the groin,