to occupy an equally strong line, and thus to prevent any active operations on the part of this army against the Richmond and Petersburg Railroad.
The powerful Confederate battery Dansler completely commanded Trent Reach — a wide, shallow part of the James River on the north flank of the contending lines.
This barred all approach toward Richmond on the part of the United States war vessels.
General Butler, conceiving the idea of cutting a canal through the narrow neck of land, known as Dutch Gap, for the passage of the monitors, directed me to report on the practicability of this project.
The report being favorable, ground was broken August 10th, 1864.
The canal, cutting off 4 3/4 miles of river navigation, was only 174 yards long — the excavation being 43 yards wide at the top, 27 yards at water-level, and 13.5 yards at a depth of 15 feet below water-level; 31 yards deep at the north-west end and nearly 12 yards at the south-east end; the total excavation being very nearly 67,0