of 3 or 4 feet above the usual summer level overflows large areas. The bottom is usually cleared and cultivated, but intersected with deep ditches. The high lands rise on each side of the bottom with moderately steep slopes to a height of 70 or 80 feet. When we reached the New Bridge, and for a week thereafter, the stream, though somewhat swollen, did not overflow at all its margins, though the swamp proper was filled with water. The first day I caused it to be reached and forded, and a few days after, when we had driven the enemy's pickets from the immediate vicinity, I caused it to be waded from the New Bridge site down about a quarter of a mile. Materials for bridging the stream were deposited at three points under shelter of the swamp timber-the New Bridge site, three-quarters of a mile above, and about the same distance below.

The corps of Heintzelman and Keyes had advanced over Bottom's Bridge on the Wiliamsburg road to Seven Pines, a point from which the Nine-mile road diverged, running nearly north to its intersection with the New Bridge road at Old Tavern. General Sumner's corps was intermediate between New and Bottom's Bridges, and had thrown two log bridges across the swamp and stream in his front. It was believed that, with the co-operation of the left and center, the passage at this point could be forced. The expedition to Hanover Court-House probably delayed the execution.

On Friday, May 30, a violent rain-storm set in, and it rained in torrents during the night.

On saturday the enemy attacked our left. Sumner with difficulty got his two divisions and one battery over. The commanding general directed the bridges here to be thrown that night. The attempt was made, but it was very dark; the stream was rising rapidly. A greater part of the night was spent in rescuing from the flood the materials of the upper bridge. Captain Duane succeeded in getting in a pontoon bridge at the site of New Bridge at 8.15 Sunday morning. At the lower bridge the darkness and rising waters prevented any progress in the night, and after making some progress during the day it was found that the direction, well adapted to the ordinary stage of the stream, had to be changed.

It was 2 a. m. of Monday before a bridge was completed. The upper trestle bridge had been made practicable for infantry by 12 m. on Sunday; but these bridges were all mere bridges in the air. The flow extended over the bottom lands and the single causeway New Bridge partially submerged, and for half a mile, with water on each side, was the sole practicable route for troops or artillery, and it evidently [was] impracticable in the military sense to pass an army in column over the route while under fire of the enemy from the heights beyond. Since the date of the battle the approaches to the bridges have been improved and the debouches corduroyed as far as the enemy's fire would permit and new bridges undertaken at other points.

The engineer officers are distributed as mentioned in the beginning of this letter. The only engineer officer with the corps engaged on Saturday and Sunday was Lieutenant McAlester. He was absent on a reconnaissance in the commencement of the battle on Saturday and on sunday the engagement was mainly with Sumner's corps. Intrenchments had been commenced at the position occupied by General Casey's division under direction of Lieutenant McAlester, but they were very incomplete. Captain C. S. Stewart was relieved, on account of sickness,