small bore that had characterized warships in the past, Ericsson opted for only two guns of large caliber; he wanted to use guns, but had to settle for Dahlgren guns when the larger size were unavailable. These were mounted in a cylindrical turret, in diameter, high, covered with iron thick. The whole rotated on a central spindle, and was moved by a steam engine that could be controlled by one man. Ericsson was afraid that using the full 30 pounds of black powder to fire the huge cannon would raise the risk of an explosion in the turret. He demanded that a charge of 15 pounds be used to lessen this possibility. As with Virginia, trials found that a full charge would pierce armor plate, a finding that would have affected the outcome of the battle. A serious flaw in the design was the pilot house from which the ship would be conned, a small structure forward of the turret on the main deck. Its presence meant that the guns could not fire directly forward, and it was isolated from other activities on the ship. Despite the late start and the novelty of construction, Monitor was actually completed a few days before her counterpart Virginia, but the Confederates activated Virginia first. Opposing forces Union Confederate Battle Command The Confederate chain of command was anomalous. Lieutenant Catesby ap Roger Jones had directed much of the conversion of Merrimack to Virginia, and he was disappointed when he was not named her captain. Jones was retained aboard Virginia, but only as her executive officer. Ordinarily, the ship would have been led by a captain of the Confederate States Navy, to be determined by the rigid seniority system that was in place. Secretary Mallory wanted the aggressive Franklin Buchanan, but at least two other captains had greater seniority and had applied for the post. Mallory evaded the issue by appointing Buchanan, head of the Office of Orders and Detail, flag officer in charge of the defenses of Norfolk and the James River. As such, he could control the movements of Virginia. Technically, therefore, the ship went into the battle without a captain. On the Union side, command of the North Atlantic Blockading Squadron was held by Flag Officer Louis M. Goldsborough. He had devised a plan for his frigates to engage Virginia, hoping to trap her in their crossfire. In the event, his plan