Lieutenant George Dewey, after his experience on the Mississippi, had served for a time in the James River flotilla under Commander McComb, and then was ordered to the Colorado, in which he participated in both attacks on Fort Fisher.

An accidental explosion of a boat load of powder, a short time before, which produced a concussion that shook down buildings, suggested the possibility of damaging the fort by similar means, and it was resolved to try the experiment. An old steamer filled with powder and disguised as a blockade runner was taken in close to the fort in the night of December 23d and exploded within three hundred yards of the beach. But no effect whatever was produced upon the fort or its equipment.

The next day two thirds of the fleet—the remainder being held in reserve—steamed slowly in, anchored in their appointed order, and began a bombardment, directing their fire principally at the guns of the fort. This was kept up all day, and there was such a play of bursting shells over and within the works as never had been seen before. Two magazines were exploded, and several buildings were burned. The fire was returned by the fort, and some vessels were injured by the shells, but no casualties resulted from it except by the explosion of a shell in the boiler of the Mackinaw. There were serious casualties in the fleet, however, from the bursting of hundred-pounder rifled guns. There were four of these accidents, by which fifteen men were killed and twenty-two wounded.

The next day, which was Christmas, the troops were landed from the transports, and the fleet renewed the bombardment in the expectation that the troops would be marched to the rear of the fort and storm it. But General Butler and General Weitzel made a reconnoissance, and agreed that the works could not be carried by assault. They therefore re-embarked the troops and steamed back to Fort Monroe. In the two days the fleet had fired fifteen thousand shells, and disabled nine guns in the fort.

This fiasco was a disappointment and mortification to the President and General Grant, who believed they had furnished a force to which they had a right to look for substantial results. They therefore resolved upon a second attempt, and this time the command of the troops was intrusted to General Alfred H. Terry. Porter's fleet renewed its supplies of coal and ammunition, and at the same time kept up a moderate fire on the fort to prevent repair of the works or erection of new ones.

Terry's transports arrived the first week in January, in the midst of a heavy storm. But the vessels rode it out safely, and then preparations were made for an early assault. On the 13th the fleet anchored as near the fort as the depth of water would permit, in the same order as before, and bombarded nearly all day while the troops were debarking. A curious incident occurred when they shelled the woods back of the fort; several hundred cattle there, intended for the garrison, were frightened by the bursting shells and rushed down to the beach, where Terry's men secured them.

Admiral Ammen, who commanded the Mohican in the first division, says: "As the sun went down and the shadows fell over the waters, the spectacle was truly grand; the smoke rose and partially drifted off, permitting glimpses now and then of the earthwork, and the fitful yet incessant gleams from the hundreds of shells bursting on or beyond the parapet illuminated, like lightning flashes, the clouds above and the smoke of battle beneath."

General Terry gave his troops a day to rest, get over the effects of the sea voyage, and throw up intrenchments across the peninsula two miles above the fort. The 15th was fixed upon for the grand assault, and the entire fleet had orders to move up and bombard at an early hour. Admiral Porter thought to assist the army further by detailing sixteen hundred sailors and four hundred marines to land on the beach and assail the sea face of the fort while the army stormed the land side. The sailors were armed with cutlasses and revolvers, and looked upon this new service as a sort of lark, but they found it a serious matter before the day was over. They came in several detachments, from different ships, and, never having been drilled together for any task of this kind, did not know how to work together. But, even if they had, it is doubtful if they could have accomplished anything; for, though they sprang to the assault nimbly enough, a large part of the garrison were called to that side of the work to repel them, and before they could get near enough to use their pistols their ranks were so thinned by grape shot and musketry that they were compelled to fall back and seek shelter. Three times they were rallied by their officers, and once they got within fifty yards of the parapet: but the murderous fire from a dense mass of soldiers behind it was too much for them. Four of their officers were killed and fifteen were wounded, while the number of sailors killed or wounded was about three hundred.

But though this assault by the sailors and marines was a failure in itself, it assisted the work of capture by calling a considerable part of the garrison to the sea face while the army assailed the rear of the fort. And the bombardment by the fleet was much more effective than in the first battle. Colonel Lamb, who commanded the fort, says: "In the former bombardment the fire of the fleet had been diffuse, but now it was concentrated and the definite object was the destruction of the land defenses by enfilade and direct fire. All day and night of the 13th and 14th the navy continued its ceaseless torment; it was impossible to repair damages at night on the land face. The Ironsides and the monitors bowled their eleven and fifteen-inch shells along the parapet, scattering shrapnel in the darkness. We could scarcely gather up and bury our dead without fresh casualties. At least two hundred had been killed and wounded in the two days since the fight began."

In those three days the fleet fired nearly twenty-two thousand shells. Terry's troops worked up to positions near the fort, and on the 15th, when the fleet gave the signal for assault by blowing the steam whistles, rushed to the work. In spite of all obstructions, they gained the parapet; but this was only the beginning of the task, for the work was provided with heavy traverses, and the defenders had to be driven from one to another of these, fighting obstinately all the way, until the last was reached and surrender could no longer be avoided. The assailants had lost about seven hundred men, killed or wounded. When Fort Fisher fell, the minor defenses at the mouth of the Cape Fear fell with it, and the port of Wilmington was closed. General Lee, then besieged at Petersburg by Grant, had sent word to its commander that Fort Fisher must be held or he could not subsist his army.