front of the Fifth Corps were soon silenced and his fire in front of the Ninth confined to a battery on the hill behind the mine A (see sketch) and to one gun from his work B, next south of the mine, which could not be effectually reached by the guns in front of it, and which was sheltered from the fire of Batteries Nos. 20 to 24 by the trees in front of the latter, which had not been falled by the troops as required. This work having been delayed by the Ninth Corps until the night of the 29th, it was then objected by General Burnside that the noise of chopping would alarm the enemy, and that it could be done after the mine was sprung. The battery in which this one gun was placed was expected to be in our possession within a few minutes after the explosion, but was not taken possession of by our infantry. The Battery A on the crest behind the mine and near a place known as the Chimneys, opened from time to time, but was always silenced by a few rounds from Brooker's battery and the field guns which could be turned upon it. As a whole the practice was excellent, keeping down the enemy's fire, destroying the embrasures, especially of the enemy's redoubt and works at the angle, exploding one of his magazines and several caissons, and preventing troops passing by the direct line from his right to the point of attack. At 10 a.m. orders were given for the withdrawal of the troops, which was covered as far as possible by the artillery. Our works were so well constructed and the fire of the enemy's batteries so effectually kept down that the casualties were few. Major Fitzhugh, First New York Artillery, is included in the list of wounded.

I have to acknowledge my indebtedness in these operations to Colonel H. L. Abbot, Firt Connecticut Artillery and captain Engineers, U. S. Army, commanding siege train; Colonel C. S. Wainwright, First New York Artillery, chief of artillery, Fifth Corps; Lieutenant Colonel J. A. Monroe, First Rhode Island Artillery, chief of artillery, Ninth Corps; Colonel A. Piper, Tenth New York Foot Artillery and captain Third U. S. Artillery, chief of artillery, Eighteenth Corps; and Lieutenant Colonel E. R. Warner, First New York Artillery and first lieutenant Third U. S. Artillery, inspector of artillery on my staff.

Colonel Abbot was indefatigable in his labors. When the order was received by him to send the siege guns and material to the lines, it was on board ship at Broadway Landing, seven miles distant, but the same night he had the sixteen heavy mortars, with all the ammunition and material in their batteries, ready for service at the required moment, and Colonel Abbot took immediate command of the 10-inch mortar battery during the bombardment.

Colonels Wainwright and Piper and Lieutenant-Colonel Monroe were also prompt and effective in getting their batteries in position and superintending their respective lines during the action. At 11 p.m. July 30 orders were received by me to withdraw so much of the siege train as was in front of the Fifth and Ninth Corps and part of that in front of the Eighteenth and move it to City Point. The order was telegraphed to Colonel Abbot immediately, and in thirty-six hours fifty-two heavy siege guns and mortars, with their ammunition, platforms, equipments, and other material, were secretly and safely withdrawn, moved by land seven miles to Broadway Landing, and loaded on barges. A few siege guns and mortars were left on the Eighteenth Corps front to control the enemy's batteries on the opposite side of the river.

Since July 31 various changes have taken place as necessity required in the position of the batteries on the lines and in the armament of the works; but no operations of importance have been undertaken, the batteries being employed principally to keep down the enemy's fire.