CAMP NEAR JAMES RIVER, VA.,

July 4, 1862.

SIR: I have the honor to make the following report relative to the operations of the Fourth U. S. Infantry since June 25, 1862:

The regiment left camp near Gaines' Mill and New Bridge, Va., on the 25th June, and marched in the direction of the Old Church, at the Totopotomoy Creek, bivouacked until next day, and returned to camp about 7 a.m. Struck our camp near Gaines' Mill and New Bridge on the afternoon of the 26th; sent the baggage to Camp Lincoln, and moved out in the direction of Mechanicsville, formed line of battle, and remained in line all night.

On the morning of the 27th crossed the creek at Gaines' Mill and took up a position for battle near the mill to support Weed's battery, which was afterward re-enforced by Tidball's. The enemy vigorously attacked our position with artillery between 11 and 12 o'clock a.m. As soon as the enemy opened fire Major D. Davidson, commanding the regiment, left the field, saying he was going for re-enforcements. He returned shortly afterward, and directed me to move the regiment by flank to the right about its length. He then almost immediately retired to the rear without informing any one of his intentions, and has not been heard of since. He left his horse on the field with hid orderly. As soon as I became satisfied that Major Davidson had abandoned his regiment I assumed command, and moved its position to one which it retained until sunset. The regiment was, with but slight intermission, under fire of the enemy's artillery from 12 o'clock until dark. They made three attempts in force to drive Captains Weed's and Tidball's batteries from their positions, but were repulsed with great slaughter. At dusk the firing and cheering on our left induced me to believe our troops were retiring, and the captains of the batteries saying they were nearly out of ammunition and about to retire, I at once threw the regiment on their left, between them and their enemy, keeping in their rear, while they withdrew in excellent order, exposing my right and front to the enemy's fire. After the batteries retired, seeing none of our troops on the field to our left except a few stragglers, I slowly followed the batteries in excellent order, under a fire of artillery and musketry, carrying off our wounded, having previously buried our few dead on the field. Bivouacked on the east side of the Chickahominy, covering Grapevine Bridge.

On the morning of the 27th I found Lieutenant John Whitney, Third Infantry, with his company on picket on my right and front. He was doing such excellent service that I directed him to remain there, and only had him recalled after the batteries withdrew. He was very efficient. Lieutenant J. A. Duvillard, Twelfth Infantry, also reported to me with a few men, having been separated from his picket. He remained with me until the next morning.

At sunrise on the 28th marched to Woodbury's Bridge (Grapevine Bridge having been partially destroyed) and crossed to Camp Lincoln- the last regiment to cross the Chickahominy River. At 10 a.m. the regiment was placed on picket on the west side of the rear, near Grapevine Bridge, which they fired and completely destroyed. Was relieved during the afternoon by cavalry pickets. At sunset left Camp Lincoln, marched all night, passing through Savage Station and White Oak Swamp, and halted at the head of Quarker road at 8 a.m. the 29th. Bivouacked in line of battle until the morning of the 30th, then moved to Malvern, near James River, where the regiment was placed in line of battle.

On the 1st of July the enemy attacked in force. The regiment having been ordered to advance with General Butterfield's brigade and to use the bayonet, about dark on the 1st of July one of our batteries fired two rounds of canister on my rear and not more than 200 yards from me, which killed and wounded some of my men. Fortunately we were lying down at the time or the loss would have been very severe.

The regiment was one of the four regular regiments forming the First Brigade of Regulars, commanded by Lieutenant Colonel R. C. Buchanan, that slept on the battle-field in advance of the line of the battle formed by our troops in the morning. The morning of the 2nd of July the regiment formed the rear of the rear guard until we left the field of battle. Camped that night near Harrison's Landing, on the James River. On the morning of the 3rd marched one mile to our present camp.

The list killed, wounded, and missing accompanies this.* During the entire operations the officers and men behaved with exemplary coolness, and carried out all my orders most cheerfully, promptly, and to my entire satisfaction.

I am, sir, very respectfully, your obedient servant,

JOS. B. COLLINS,

Captain, Fourth Infantry, Commanding Regiment.

Lieutenant WILIAM H. POWELL,

Adjt. Fourth Inft., Actg. Asst. Adjt. General, First Brigadier Regulars.