flag-ship to arrange the plan of battle.
There was a perfect understanding between the two commanders, and a system of signals was established by which they could communicate, though a mile apart, and in the midst of battle.
It was agreed that a heavy bombardment from all the naval vessels should begin at an early hour, and continue up to the moment of assault, and that even then it should not cease, but be diverted from the points of attack to other parts of the work.
The assault was to be made at three P. M.; the army to attack on the western half of the land face nearest the river, and a column of marines and sailors, armed with cutlasses and revolvers, to move against the north-east bastion.
The fire of the navy was continued during the night, to exhaust the garrison and prevent them from repair.
One vessel was employed at a time, each firing one hour, when it was relieved.
At daylight on the 15th, the monitors and the eleven-inch gunboats again commenced battering the work, and at ten o'clock all the vessels, except a division left to aid in the defence of Terry
's northern line, moved into position, each opening a powerful and accurate fire as they got their anchors down.
For six hours the mighty fleet, in three divisions, with an armament of nearly six hundred guns, poured torrents of shell and metal missiles on every spot of earth about the fort.
The guns in the upper batteries replied as on the day before, and Mound Hill battery, at the southern extremity, kept up an especially galling fire, but no vessel was injured enough to interfere with her efficiency, and the rebels were finally driven from their pieces and into the bomb-proofs along the entire extent of the parapet.