the union army maintained a constant rotation of soldiers to man the forward trenches of the "grand guard". during the evening of august 16 a confederate artillery shell burst through the bombproof serving as the headquarters for colonel joshua b. howell, commanding officer of the grand guard that evening. a shell fragment struck colonel howell, wounding him severely in the head. despite howell's quick recovery, the incident prompted the union commander to exclusively use veteran troops in the forward trenches. confederates also kept a constant rotation of soldiers through fort wagner and battery gregg. during the night, rowboats would bring fresh troops from the mainland to replace the garrison. even though they had won a substantial victory at fort wagner, the confederates fully expected the campaign to continue. having a large garrison to draw from gen. p.g.t. beauregard was prepared to continue the campaign. immediately in command of confederate forces surrounding charleston was former career army officer and south carolina businessman roswell s. ripley. ripley's forces were spread throughout fortifications surrounding charleston harbor and included a division of local south carolina militia. gilmore and admiral john a. dahlgren requested reinforcements from general-in-chief henry halleck. halleck was reluctant but nevertheless a division from the army of the potomac was transferred to the south under george h. gordon. general john g. foster, union commander of the department of north carolina, enthusiastically sent a division of reinforcements telling gilmore "charleston is too important to be lost when so nearly won".