the bridge over the James, containing 101 wooden pontoons. In the channel the depth of water was twelve to fifteen fathoms, the tidal current strong, rising and falling about four feet. In the channel pontoons were anchored to vessels above and below moored for that purpose. The bridge was commenced from each end, and built by successive pontoons and by rafts. It was commenced about 4 p. m. on 15th of June, two companies at each end, under the direction of Major Duane, chief engineer. Later in the afternoon and after considerable progress had been made, General Benham took command. The bridge was completed except a passage-way of 100 feet for vessels, and the raft constructed to fill this gap by 11 p. m. The greater part of the infantry and artillery, all the wagon trains, and droves of beef-cattle of the army passed this bridge safely and without interruption, except such as resulted from a vessel moored above slipping her anchor, thereby carrying away a part of the bridge, which, however, was promptly restored.

On 6th of June Captain Turnbull was, by direction of the chief engineer, assigned to the Cavalry Corps and did no further duty with the battalion, and about the same time Lieutenant Mackenzie took command of the Second Connecticut Volunteer Artillery, and was relieved from duty with the battalion.

During the earlier active operations about Petersburg the officers were employed in reconnaissances under the direction of the chief engineer.

Lieutenant Benyaurd, with Company A, reported for duty to General Burnside, commanding Ninth Corps, on the 25th of June and remained four weeks.

On the 23rd two batteries were constructed on the Second Corps line by Sergeant Grant and 100 men of the battalion, under the direction of Colonel J. C. Tidball, Fourth New York Artillery.

In the early part of July a line extending from the left of the Fifth Corps front where it crosses the Jerusalem plank road to the southeast for about a mile, then to the east for about one mile and a half, terminating near Wells', on the Blackwater Swamp, was put in a condition for defense. The following is the arrangement:

First. A redoubt, nearly square, 400 feet side, parapet 12 feet thick and 7 feet high, with emplacements for ten guns, situated near the plank road and south of it-900 yards from the point where the line crosses the plank road.

Second. a redout 200 feet square, north of the plank road and east of the Chieves house, 600 yards from the first parapet, of same height and thickness, and places for six guns in embrasure, six in barbette.

Third. A battery and rifle pit for support near Chieves' house.

Fourth. A redoubt 200 feet square, near Wells', on the extreme left, for six guns in barbette, fourteen in embrasure.

Fifth. The timber in front of this line for several hundred yards cut down, making the front almost impenetrable for an attack in organized masses.

This work was done under the direction of engineer officers and superintendence of enlisted men of this command by details from Fifth, Second, and Ninth Corps.

Captain F. Harwood reported for duty on July 9, and was assigned to the command of Company D.

The following is a summary of the work done under the direction of engineer officers (between July 11 to 30) of this command in obedience to the instructions of the chief engineer, dated July 9, which assigned