On Monday, the 4th instant, the enemy retook possession of Fredericksburg Heights. Howe's division was at once formed to the rear (east), to meet any attack from heat direction, Newton's division formed to the front (west), and Brooks' division formed to the south, his right joining Newton's left and his left How's right. On howe's line, Martin's and Rigby's batteries were placed in position, Rigby's and one section of Martin's one the right, the remaining two sections of Martin's on the left. McCartney 's and Hexamer's (Parsons') batteries were placed in position on Brooks' line, McCarney's and one section of Hexamer's (Parsons') on the right, the remarrying two sections of Hexamer's (Persons') on the left. On Newton's line, Butler, Harn, and Cowan were in position on the left center, near the toll-gate, and Willson's and McCarthy's were placed in a commending position in the rear of the right counter. A brigade of the enemy which attacked Howe in the morning was repulsed by the fire of the line of skirmishers and the section of 12-pounder guns of Martin's battery.

In the evening a most determined attack was made upon Howe's front, the enemy advancing upon Brooks' front at the same time. Three times their column advanced upon Brooks, to be as often driven back by the fire of the skirmishers and McCartney's and Hexmer's (Parsons') batteries. McCartney's practice was very fine; he not only rendered valuable assistance in dispersing the infantry of the enemy, but when they subsequently brought up a section of a battery and attempted to put it in position, he prevented them from doing so, driving the gunners from their pieces and preventing their firing a shot.

In the attack upon Howe, Martin and Rigby both did excellent execution, fighting desperately, but with coolness and judgment, and only falling back to a second position when their supports had left them.

Butler's battery was sent from the right to General Howe late in the evening, arriving there just after his first line had been driven in. The battery was placed so as to command a ravine by which the enemy were approaching, and his well-directed fire soon checked their advance. Rigby's second position was some 200 yards to the right of Butler,and Martin's some 200 yards to the left and center, Butler being in the center, rigby on the right center, and Martin the left center of Howe's second line. In his attack upon this line, the enemy was repulsed with great slaughter, the batteries rendering very efficient service.

During the night, the batteries fell back to Banks' Ford, and, crossing with the corps to the north bank of the river, went into camp about 6 a. m. on the 5th, about a mile back from the ford, on the Falmouth road.

At 10 a. m. Williston was, by order of General Sedgwick, sent to Richards' Ford. He reported back on the 7th.

On the 8th, the batteries returned to the vicinity of their former camps.

I cannot close this report without speaking in the highest terms of the coolness, bravery, and efficiency of the officers and men of the artillery of this corps. I claim for them that to these qualities, which they possess in so eminent a degree, is due much of the success of the Sixth Corps.

On Sunday, and again on Monday, when our infantry was driven back by the greatly superior numbers of the enemy, our artillery checked his advance and turned the tide of battle.

To Major J. A. Tompkins, First Rhode Island Artillery, commanding Artillery Brigade, First Division, I am greatly indebted for most valuable assistance. He again, as he has so often before, proved himself to be an officer thoroughly acquainted with his profession, and possessed of great coolness and personal courage. Captains McCartney, Cowan, Rigby,