Numbers 23. Report of Lieutenant Colonel Joseph B. Leake, Twentieth Iowa Infantry.

HDQRS. TWENTIETH Regiment IOWA VOLUNTEER INFANTRY, Camp at Prairie Grove, Ark., December 9, 1862.

I have the honor to report the part taken by the Twentieth Regiment of Iowa Infantry in the battle of Prairie Grove, fought on the 7th instant. I think it necessary, in order to have full justice done to the regiment, to state by what marches it arrived upon the field.

On the morning of December 4, at 4 o'clock, we left Camp Lyon, 22 miles from Springfield, Mo., on the road to Cassville, and marched to the Three Widows, 12 miles from Cassville, and on the following day we moved at 5 a. m., marched through Cassville and Keytesville to camp, 2 miles from Keytesville.

On the morning of the 6th instant we moved at 5 o'clock, and, passing Elkhorn and Sugar Creek, arrived at Cross Hollow about 5 p. m. Bivouacked till 10 o'clock, and again commenced the march. Marched all night. Passed through Fayetteville,and halted for breakfast about 1 mile beyond.

After remaining one hour, we marched on rapidly until we arrived upon the field of battle, about 12 m. of the 7th instant, thus having marched a distance of 100 miles in eight consecutive hours, the last 57 miles of which we passed over in thirty-one consecutive hours.

Very many of my command marched with shoes so much worn that their feet were on the ground, and were badly bruised and cut up by the stony roads. A few had been supplied with boots at Camp Lyon, which fitted them so illy that their feet became much blistered and inflamed by the continuous marching. A few of these last mentioned carried their boots and marched in their bare feet to the scene of action.

Under these circumstances we went into the engagement with only 270 enlisted men and 23 officers. I neglected to mention, however, that before moving from our halting-place near Fayetteville, having learned of the capture of a portion of the train of the First Arkansas Cavalry a few miles beyond, I was ordered to detail a company, under a reliable officer, to protect our train, for which duty I assigned Company B, under the command of Captain [E.] Coulter, so that Company B was deprived the privilege of being present at the engagement, except 3, who joined other companies.

Pursuant to orders, the regiment was drawn up in line of battle in an open field to the right of the road, a short distance from the creek, and 50 yards in the rear of the Thirty-seventh Illinois. After remaining in this position a few minutes, we moved forward by the right flank, following the Thirty-seventh Illinois, wading the creek, and formed in line of battle in the rear of and supporting three pieces of Battery F, First Missouri Light Artillery, and under shelter of the hill upon which the battery was in position, Immediately after forming in line, I was ordered to throw out a party of skirmishers to protect our right flank and rear from surprise, for which service I detailed 20 men of Company A, under the command of First Lieutenant [C. L.] Drake, of that company.

At or near 2 p. m.the battery was moved forward, and we moved forward in line of battle of the middle of the field on the right of the main road and in front of the while house, on the road to the top of the hill. By order of Colonel Dye, I immediately moved the regiment to the right, into the adjoining field and in front of the orchard, to check a movement of the enemy on our right flank. Here we were exposed to the fire of the enemy for a short time, which we returned, advancing a short dis-