Capt. John C. Mitchel, who was killed in July 1864 during the third great bombardment after commanding only two months and 16 days.
Capt. Thomas A. Huguenin, who remained in charge until Charleston and Fort Sumter were evacuated in February 1865.
On July 7, 1864, Foster’s batteries opened a sustained bombardment against the ruin of Fort Sumter. During the remainder of that month, an average of 350 rounds daily were hurled at the beleaguered fort. In some respects, this was the heaviest bombardment Fort Sumter had yet received. Although the gorge ruin was wasted away at one point to within 20 feet of the water, and the shattered sea front was still further reduced, the right face remained erect, its three-gun battery intact; likewise most of the left flank. To Admiral Dahlgren, as late as July 21, the work seemed “nearly impregnable.” Debris added to debris, feverish work day and night, and thousands of bags of sand brought from the city by night actually made the fort stronger than ever. If a casemate were breached, it was speedily filled; if the slopes of the ruin invited assault, a bristling array of wooden pikes and barbed-wire entanglements were provided; and there were always the muskets of the 300-man garrison.
The fire slackened in August; Foster’s supply of ammunition dwindled, and his requisitions for more went unfulfilled. A scheme for “shaking down” the fort walls by floating down large “powder rafts” failed miserably. Mid-August brought final War Department refusal to supply light-draft steamers; the end of August, sharp disapproval of Foster’s “assaulting arks.” Meanwhile, Dahlgren had been unwilling to cooperate in an alternate plan of assault and Foster himself was ordered to remain strictly on the defensive. He was also called upon to ship north most of his remaining ammunition and four more regiments of troops to be used in Grant’s operations against Richmond.
On September 4, the bombardment begun on July 7 came to an end. In those 61 days, another 14,666 rounds had been hurled against the fort. Sixteen of the garrison had been killed, 65 wounded. On July 20 Captain Mitchel fell mortally wounded. Capt. Thomas A. Huguenin succeeded him that night.
Maj. Gen. John G. Foster, who replaced Gillmore as commander of land operations at Charleston. Foster had been Anderson’s engineer officer at Fort Sumter during the 1861 bombardment.
The last great bombardment of Fort Sumter had taken place. The firing was no more than desultory after September 1864; less than a hundred rounds were hurled at the fort in the months of December and January; none at all in February. During the autumn months it was all Foster’s batteries could do to make a reasonable defense of Morris Island, let alone carry on any offensive operations.