Numbers 310. Report of Lieutenant Colonel Herbert von Hammerstein, Seventy-eighth New York Infantry.

LITTLESTOWN, PA.,

July 6, 1863.

CAPTAIN: I have the honor to report the part which my regiment took in the engagement on July 2, 3, and 4. On the morning of the 2d, about 6 o'clock, my regiment took position on the left of the brigade, in line of battle, having, the Sixtieth New York Volunteers on its right and the First Army Corps on its left. It covered part of the crest of a steep hill. A breastwork of trees and dirt was soon thrown up, and the day passed till about 4 o'clock without any incident. At about that time a battery of the enemy, numbering eight pieces, opened on a battery on our left, the shots passing our line without doing injury, when Battery K, Fifth U. S. Artillery, with two 10-pounder Parrott and two Napoleon guns was at 4. 30 o'clock ordered up to occupy the position which my regiment occupied and silence the rebel guns. I fell back a few yards to the rear of the battery, and remained there during the artillery contest. The firing of this battery was masterly; at 5. 30 o'clock every gun of the enemy was silenced, the battery losing several of their gunners and drivers. My men volunteered to supply their places, and, besides, assisted during the whole engagement in carrying ammunition from the caissons to the guns. We only lost 1 man killed and 1 wounded at that place. At about 6 o'clock the battery was withdrawn, and, after reoccupying my old position, I received orders from Brigadier-General Greene to relieve the Twenty-eighth Pennsylvania Volunteers as skirmishers with my regiment. I at once marched the regiment down to the center of our brigade, crossed the breastworks, and deployed my skirmishers, not being able to see the Twenty-eighth Pennsylvania Volunteers, and having no time to look for them, as the enemy was already pressing all the skirmishers back, Our skirmishers came in soon, and, after giving and receiving some severe volleys of musketry, we fell back across the breastworks. The whole line behind the works was then occupied by our brigade, no interval existing. General Greene ordered me to fall in, with my regiment in front of me, which I did. I joined the One hundred and second New York, and we, with the rest of the brigade, succeeded in repulsing a most furious attack of the enemy, beginning at 6. 40 o'clock and ending at 9. 30 o'clock, when the enemy fell back, and we fired our last round of ammunition. The rest of the night we remained behind the breastworks under arms, only annoyed by sharpshooters. Filling our boxes with ammunition, at 3. 30 a. m. I received orders to occupy a place between the One hundred and second and Sixtieth Regiments, which was done immediately, and ten minutes afterward the attack began with the same energy which the rebels displayed on the evening before. Our men succeeded in repulsing them totally, with the same coolness and determination, before 6 a. m. At 7. 40 o'clock my regiment was relieved by the One hundred and fiftieth New York Volunteers, to rest and clean their guns. At 9 a. m. we reoccupied our old place, remaining there until 1 p. m., only annoyed by sharpshooters. At 1 o'clock we were relieved again.