Official Records of the Rebellion

[p.12]

I had provided a small siege train and moderate supplies of intrenching tools for such a contingency as the present. Immediate steps were taken to secure the necessary additions. While the engineer officers were engaged in ascertaining the character and strength of all the defenses and the configuration of the ground in front of Yorktown in order to determine the point of attack, and to develop the approaches, the troops were occupied in opening roads to the depots established at the nearest available points on branches of York River. Troops were brought to the front as rapidly as possible, and on the 10th of April the army was posted as follows:

Heintzelman’s corps, composed of Porter’s, Hooker’s, and Hamilton’s divisions, in front of Yorktown, extending in the order named from the month of Wormley’s Creek to the Warwick road opposite Wynn’s Mill; Sumner’s corps—Sedgwick’s division only having arrived—on the left of Hamilton, extending down to Warwick and opposite to Wynn’s Mill works; Keyes’ corps (Smith’s, Couch’s, and Casey’s divisions), on the left of Sedgwick, facing the works at the one-gun battery, Lee’s Mill, &c., on the west bank of the Warwick.

Sumner, after the 6th of April, commanded the left wing, composed of his own and Keyes’ corps.

Throughout the preparations for and during the siege of Yorktown I kept the corps under General Keyes, and afterward the left wing, under General Sumner, engaged in ascertaining the character of the obstacles presented by the Warwick, and the enemy intrenched on the right bank, with the intention, if possible, of overcoming them and breaking that line of defense, so as to gain possession of the road to Williamsburg and cut off Yorktown from its supports and supplies. The forces under General Heintzelman were engaged in similar efforts upon the works between Wynn’s Mill and Yorktown. General Keyes’ report of the 16th of April, inclosing reports of brigade commanders engaged in reconnaissances up to that day, said “that no part of his (the enemy’s line opposite his own) line, so far as discovered, can be taken by assault without an enormous waste of life.”

Reconnaissances on the right flank demonstrated the fact that the Warwick was not passable in that direction except over a narrow dam, the approaches to which were swept by several batteries and intrenchments, which could be filled quickly with supports sheltered by the timber immediately in rear.