THIRD BRIGADE.

Eighty-third Regiment New York Volunteers:

Captain John Hendrickson.

Captain Moesch.

Thirteenth Regiment Massachusetts Volunteers:

Major Gould.

Eleventh Regiment Pennsylvania Volunteers:

Adjutant Uncapher.

Lieutenant Thomas.

Twelfth Regiment Massachusetts Volunteers:

Captain Allen.

Lieutenant Clark.

Lieutenant Dehon.

Captain B. F. Cook.

R. COULTER,

Colonel, Commanding Third Brigade.

Respectfully submitted.

JAMES B. RICKETTS,

Brigadier-General Volunteers, Commanding Division.

No. 28. Report of Captain James MacThompson, One hundred and seventh Pennsylvania Infantry, First Brigade, of the battles of South Mountain and Antietam.

HDQRS. ONE HUNDRED AND SEVENTH PENNSYLVANIA VOLS.,
Camp near Mercerville, Md., October 7, 1862.

SIR: I have the honor to make the following report respecting the One hundred and seventh Regiment Pennsylvania Volunteers in the two actions, September 14 and 17, at South Mountain and Antietam:

Arriving at the base of South Mountain, after a wearisome march of 17 miles, on September 14, at about 5,30 o'clock p. m., we found the enemy fiercely engaged with the Pennsylvania Reserves. Immediately, in compliance with orders from General Duryea, formed in line of battle near the foot of the hill, and gave orders to move forward with fixed bayonets. Nothing could exceed the promptness of both officers and men in the execution of this order; with enthusiastic cheers they dashed forward, and soon the enemy were scattered, and in much confusion were flying before us. Several times they rallied, and once in particular, having gained an admirable position behind a stone fence, they appeared determined to hold on to the last. Here it was they sustained their greatest loss. Colonel Gayle, Twelfth Alabama, fell dead, and the lieutenant-colonel Fifth South Carolina wounded and taken prisoner.

Their stand at this point delayed not the on ward movement of the One hundred and seventh a moment, but in a little while we were over the fence and among them, taking 68 prisoners, killing and wounding quite a number, and causing the remainder to fly precipitately to the top of the mountain. Following, we drove them across the narrow plain on the summit and part way down the other side. Night ended the pursuit; but, fearing a surprise, I directed officers and men to rest in line during