15th, at daylight, were surrounded by the enemy, who opened on us a heavy fire of musketry, at the same time outflanking us by one regiment on our right. We again moved towards the right under a heavy fire and formed a new line, thereby defeating for the time the enemy's object. This ground was steadily maintained until exposed to a flanking fire upon he right from fresh troops of the enemy. With a scarcity of ammunition in a large portion of my line I deemed it my duty to give the order to retire, which was executed steadily and in good order. I at once formed a new line about 300 yards to the rear, supporting the troops on our left, and remaining there until the troops who had occupied our extreme right before our arrival were forced to retire also, when I ordered my brigade farther to the rear within our lines. I then encamped in close order, and had the company rolls called and the men supplied with food (they having had none for nearly thirty-six hours), as also ammunition to replace that expended. At 4 p. m. we were ordered to the extreme left of our lines to support the troops at this place. The Twelfth Illinois remained under arms that night in support of the battery placed in the redoubt taken by assault the previous afternoon.

16th, Sunday morning, the enemy having capitulated, I marched my command into the enemy's works, since which time they have guarded prisoners and captured stores.

I feel proud in bearing testimony to the unflinching firmness and uncomplaining conduct of the men of my command during the whole of the siege; also to their steadiness and courage displayed while under fire; and while I would not detract from any one his just dues, I must mention the gallant conduct of Lieutenant-Colonel Phillips, of the Ninth Illinois; also Lieutenant-Colonel Chetlain and Major Ducat, of the Twelfth Illinois, and Lieutenant-Colonel Tupper, of the Forty-first Illinois; also my aides, Adjt. J. Bates Dickson and Lieutenant George L. Paddock, of the Twelfth Illinois, and Lieutenant Babcock, of the Second Illinois Cavalry, for their valuable assistance. I at the same time regret that circumstances placed me for a portion of the time with each division, depriving my men of that favorable notice to which their arduous and soldierly conduct entitled them - conduct inferior to that of no troops on the field.

Trusting that an opportunity may soon occur where the same gallant conduct on the part of my command may be again displayed and appreciated, I remain, your obedient servant,

JOHN MCARTHUR,

Colonel, Commanding First Brigade, Second Division.

Captain M. BRAYMAN,

Assistant Adjutant-General.

Numbers 22. Report of Lieutenant Colonel Augustus L. Chetlain, Twelfth Illinois Infantry.

HDQRS. TWELFTH REGIMENT ILLINOIS VOLUNTEERS,
Fort Donelson, Tenn., February 18, 1862.

In accordance with Special Orders, Numbers 2, I beg leave to make the following report:

On the morning of the 12th instant the Twelfth Regiment of Illinois Volunteers, which I have the honor to command, left Fort Heiman with the Ninth and Forty-first Illinois for Fort Donelson via Fort Henry.