In 1862, Fort Pulaski was considered invincible. Its 7½-foot solid brick walls were backed with massive piers of masonry. The broad waters of the Savannah River and wide swampy marshes surrounded the fort on all sides. Ships of the Navy could not safely come within effective range of this citadel, and there was no firm ground on which land batteries could be erected nearer than Tybee Island, from 1 to 2½ miles away. All previous military experience had taught that beyond a distance of 700 yards smoothbore guns and mortars would have little chance to break through heavy masonry walls, and beyond 1,000 yards no chance at all. In referring to Fort Pulaski, the United States Chief of Engineers, General Totten, said “you might as well bombard the Rocky Mountains.” General Lee, himself, standing on the parapet of the fort with Colonel Olmstead, pointed to the shore of Tybee Island and remarked, “Colonel, they will make it pretty warm for you here with shells, but they cannot breach your walls at that distance.” In the minds of the experts a long-range bombardment would merely serve to pave the way for a direct assault. [Illustration: _Air view of Fort Pulaski._] Gillmore held a different opinion. He was familiar with the test records of a new weapon, the rifled gun, with which the Army had begun to experiment in 1859, and, on December 1, 1861, he broke with tradition and risked the laughter of his superiors. After a careful reconnaissance he reported to Sherman that it would be possible to reduce Fort Pulaski with mortars and rifled guns from Tybee Island. On this basis he submitted a complete plan for the attack on Fort Pulaski. Sherman approved the plan, but he made it clear that he doubted the usefulness of the rifled guns. In concluding his endorsement he wrote, “All that can be done with guns is to shake the walls in a random manner.” [Illustration: _Gillmore’s plan for the bombardment._ Courtesy National Archives.] _Gillmore Sets the Stage_ From the 21st of February, when ordnance and ordnance stores began to arrive in Tybee Roads, until April 9th, Gillmore gave the men of his command no rest. To put his plan for the siege into effect was a Herculean task. Materials, supplies, ammunition, and guns had to be unloaded through the surf and then transported long distances across sand and marsh. Gun emplacements, magazines, bomb-proof shelters, and roads had to be constructed. And last, but not least, gun crews had to be trained. Detailed to this back-breaking assignment were the 7th Regiment Connecticut Volunteers, the 46th New York Volunteers, two companies of the Volunteer Engineers, and, for most of the time, two companies of the 3rd Rhode Island Volunteer Artillery.