LITTLE ROCK, ARK., May 8, 1864.

CAPTAIN: I have the honor to make the following report of the operations of my command during the recent campaign in the southwestern part of Arkansas: We left Little Rock on the 23rd of March and arrived by easy marches with the army at Arkadelphia on the 29th. On the 2nd of April my command was assigned to the duty of guarding the supply train of the army. As my rear guard was passing a ravine near Terre Noir Creek, on the Arkadelphia and Washington road, Shelby's brigade attacked it, with the intention of overpowering it and cutting off our train. I had but one regiment in the rear, the Twenty-ninth Iowa Infantry, numbering about 540 men, with one section of Voegele's battery. Colonel Benton, commanding this regiment, held the enemy's entire force in check until I arrived in the rear, when, seeing the condition of affairs, I immediately sent for the Fiftieth Indiana, which was at the head of the train, about 4 miles farther on. The train, with the Thirty-third Iowa divided up among it, moved on, and was soon in a position to be safe from any attacks. After the arrival of the Fiftieth Indiana I formed my line and received the attack of the enemy, and repulsed him, with severe loss. I then moved toward the train, stopping wherever I was pressed too hard, and forming my line repeatedly repulsed their onset. After falling back in this way about 4 miles I found a detachment of four companies of the Ninth Wisconsin Infantry and a section of artillery guarding the Washington road until I should come up. This detachment of the Ninth Wisconsin was placed in the rear, and we moved on the Elkin's Ferry road. After we had turned down this road the enemy made a most determined and vigorous assault, but were repulsed by the Ninth Wisconsin and Fiftieth Indiana, and troubled us no more. I have already made full report of this action.

On the 4th of April Marmaduke, with a large force of cavalry, attacked McLean's brigade on the south side of the Little Missouri River. Under your orders two regiments of my brigade moved across to McLean's assistance. Having been directed by your to support McLean, I conferred with him in order to ascertain his exact position, so that my troops could be properly disposed. I formed my command with two companies of the Twenty-ninth Iowa in the rear of the Thirty-sixth Iowa, the other eight companies on the right. The Ninth Wisconsin was held in reserve on the north side of Howard's Creek. At this time I saw that Stange's battery, of McLean's brigade, was in direct range of the enemy's sharpshooters, and I took the responsibility to order it to move beyond Howard's Creek, where its fire would be equally effective, and at the same time the battery would be safe. The forces under my command continued in this position until the close of the engagement. On the 10th of April my brigade again met the enemy on Prairie D'Ane, where a severe skirmish ensued, in which the rebel forces were driven from their position. On the 11th of April we moved out with the rest of your command on Prairie D'Ane and offered battle, but the enemy retired to this fortifications across the prairie, and the attack was not made, owing to the lateness of the hour. On the next day we moved out to attack the enemy's works, but after a skirmish we found that they were evacuated. April 15, my brigade was ordered to take the advance to move into Camden, information having been received that the enemy was trying to reach and reoccupy that place. I came