The investment of the fort was not yet complete, but that was accomplished on March 29, when a company from Parke's brigade crossed the sound and landed unopposed on Bogue Banks. The Confederate infantry that would have defended against the landing, the 26th North Carolina, had been included in the retreat following the Battle of New Bern. Federal siege artillery followed, and Parke set up four batteries that would bear on the fort: four 8-inch (20.3 cm) mortars at a range of 1200 yards (1100 meters); four 10-inch (25.4 cm) mortars at a range of 1600 yards (1460 meters); three 30-pounder (13.6 kg) rifled Parrotts at a range of 1300 yards (1190 meters); and a 12-pounder (5.4 kg) boat howitzer at a range of 1200 yards (1100 meters). The batteries were moved up at night and remained hidden behind sand dunes until they were ready to open fire. The defenders were aware of these activities, but could not waste ammunition by firing at unseen targets. Patrols sent out from the fort to harass the Union soldiers were driven back, usually without loss. On April 17, General Burnside could state in his report to the War Department, "I hope to reduce the fort within ten days." His prediction proved to be remarkably accurate.