fantry. I was ordered to mass my brigade in the woods in the rear of the position and await instructions. At 7. p. m. I was ordered to relieve the First Brigade, then engaged on the left front, and at dark to retire my command again to the wood, which I was to hold until daylight, to enable the other brigades to retire on a suitable position near the cross-roads. Retiring as ordered, I withdrew my skirmishers to a line 500 yards in advance of my position, and connecting with the woods at the same distance on each flank, completely covering the road. I had previously strongly picketed the roads in rear toward Sharpsburg on the left and Hagerstown on the right. Lieutenant Blunt, of Sixth New York, whom I sent to the right to reconnoiter, ascertained the presence of a strong force of infantry and artillery in close proximity to my right flank. The enemy's skirmishers also commenced to feel their way on my left. About midnight, the enemy advanced on my front, and engaged the skirmishers. He was repulsed, and soon after retired. Our loss was Captain Van Buren, Sixth NEW York, 2 sergeants, and 1 private missing. Just at daybreak, I made a demonstration on the enemy's front by charging down with a squadron of the Sixth New York, driving in his skirmishers and pickets on the reserve, and throwing them in confusion, under cover of which movement I withdrew the main body 1 mile to the rear, and took up a position in front of the road running from Hagerstown to Sharpsburg. I then withdrew my skirmishers from the front and the pickets from the roads, and retired slowly, the enemy following very cautiously, and halting when my rear guard faced about. After retiring about 2. 1/2 miles, I was ordered to halt, rest men and horses, strongly picket the roads to the rear, and, if possible, hold the position until the division of General Kilpatrick and the two brigades of General Buford's division had crossed Antietam Creek. About 11 a. m. the enemy appeared in force in our rear with infantry and artillery. I immediately ordered up the Ninth New York (Colonel Sackett) to hold him in check, and sent an orderly to notify General Buford. As soon as I ascertained that the rear of General Buford's column was crossing Antietam Bridge, I ordered Colonel Sackett(who by this time was hotly engaged) to fall back on the brigade. I then took up the line of march, and followed the division, the enemy becoming bolder and closely pressing my rear, under Colonel Sackett, who fell back, fighting, his men behaving splendidly, making a stand at every favorable point, and often repulsing and punishing the enemy's sharpshooters. On arriving near the creek, I dismounted two squadrons of the Seventeenth Pennsylvania, and posted them on the hill commanding the bridge, intending to give the enemy a warm reception. He was, however, too cautious to approach the creek, which we crossed unmolested, and joined the division, having suffered a loss of 8 killed and wounded while retiring, all of the Ninth New York. That night the brigade encamped at Boonsborough.

BATTLE OF BOONSBOROUGH, MD.

The next morning, July 8, the enemy advanced in force down the Hagerstown turnpike. The alarm being sounded, I formed the brigade in line of battle along the crest in my front, and at nearly a right angle with the line of the First and Reserve Brigades, Connecting with the left of the latter and covering the approach from Will-