GENERAL GRANT ON THE SIEGE OF PETERSBURG. 575

it VN

At the request of the editors, the following account°f the Dutch Gap Canal has been prepared by GeueralT* S. Michie, engineer in charge of the work:

“The strong defensive lines of Bermuda Hundred,behind which the Army of the James retreated afterits repulse at Drewry’s Bluff, May 16th, 1864, werebadly chosen, as their location permitted the Con-federates to occupy an equally strong line, and thusprevent any active operations on the part of thisari ny against the Richmond and Petersburg Railroad.The powerful Confederate battery Dansler completelycommanded Trent Reach— a wide, shallow part of the^ames River on the north flank of the contending lines.This barred all approach toward Richmond on the part°f the United States war vessels. General Butler, con-ceiving the idea of cutting a canal through the narrowa eck of land, known as Dutch Gap, for the passage offhe monitors, directed me to report on the practicabil-lt F of this project. The report being favorable, ground^as broken August 10 th, 1864. The canal, cutting offmiles of river navigation, was only 174 yards long-ue excavation being 43 yards wide at the top, 27 yards"Water-level, and 13.5 yards at a depth of 15 feet belowWater-level; 31 yards deep at the north-west end andhearly 12 yards at the south-east end; the total excava-ficn being very nearly 67,000 cubic yards. While no se-rous civil-engineering difficulties occurred, the troopsemployed were constantly subjected to a severe con-tinuous fire, first of heavy rifled guns and afterward ofMortars. The casualties were continuous throughout,°h oue occasion resulting in twelve killed and fortybounded; in addition, great losses in mules, horses, and

EXCAVATING THE DUTCH GAP CANAL.FROM A SKETCH MADE AT THE TIME.

carts were sustained. The dredge (after beingonce sunk) and the steam-pump were bomb-proofed for protection. This constant verti-cal fire from mortar-batteries only twelvehundred yards distant delayed the work beyond an-ticipation, causing frequent suspension of all labor.The troops seeking cover in earthen dug-outs that cov-ered the site of the work were also undergoing con-stant discomfort and exposure. The greater part of theexcavation was done.by colored troops, who displayedthe greatest courage and fortitude, and maintainedunder the most trying circumstances their usual goodhumor and cheerful disposition. Owing to variouscauses, and especially to the capture by General Butlerof the outer line of the Richmond defenses on the 29thof September, the importance of the canal project sensi-bly diminished; therefore the work was much delayed,was subject to indifferent management, and was not ulti-mately completed until December 20th, 1864. The ratherlarge bulkhead containing nearly 6000 cubic yards ofearth was mined and charged with 12,000 pounds ofpowder, distributed in four charges, one being 25 feet,and three 15 feet, below the water-level. At 3:50 p. m.,January 1st, 1865, these mines were exploded by meansof a Gomez fulminate fuse so arranged as to give apoint of ignition for every one hundred pounds ofpowder. The condition of the canal in November iswell delineated in the accompanying cut. The bomb-proof steam-pump is shown in the far corner, and thebulkhead, separated from the adjacent embankmentby vertical trenches, is that which was mined andblown up. After the explosion the debris at the north-west end was partially removed by means of a steam-dredge. This canal was not of service during the war,but was subsequently enlarged and perfected, and be-came the usual channel for the passage of vessels.”

VERTICAL PLAN OF THE DUTCH GAP CANAL.