Such, in brief, was the condition of things when Colonel Rose arrived at the prison. From the hour of his coming, a means of escape became his constant and eager study; and, with this purpose in view, he made a careful and minute survey of the entire premises.
From the windows of the upper east or "Gettysburg room" he could look across the vacant lot on the east and get a glimpse of the yard between, two adjacent buildings which faced the canal and Carey street respectively, and he estimated the intervening space at about seventy feet. From the south windows he looked out across a street upon the canal and James River, running parallel with each other, the two streams at this point being separated by a low and narrow strip of land. This strip periodically disappeared when protracted seasons of heavy rain came, or when spring floods so rapidly swelled the river that the latter invaded the cellars of Libby. At such times it was common to see enormous swarms of rats come out from the lower doors and windows of the prison and make head for dry land in swimming platoons amid the cheers of the prisoners in the upper windows. On one or two occasions Rose observed workmen descending from the middle of the south-side street into a sewer running through its center, and concluded that this sewer must have various openings to the canal both to the east and west of the prison.
The north portion of the cellar contained a large quantity of loose packing-straw, covering the floor to an average depth of two feet; and this straw afforded shelter, especially at night, for a large colony of rats, which gave the place the name of "Rat Hell."
In one afternoon's inspection of this dark end, Rose suddenly encountered a fellow-prisoner, Major A.G. Hamilton, of the 12th Kentucky Cavalry. A confiding friendship followed, and the two men entered at once upon the plan of gaining their liberty. They agreed that the most feasible scheme was a tunnel, to begin in the rear of the little kitchen-apartment at the southeast corner of Rat Hell. Without more ado they secured a broken shovel and two case-knives and began operations.
Within a few days the Confederates decided upon certain changes in the prison for the greater security of their captives. A week afterward the cook-room was abandoned, the stairway nailed up, the prisoners sent to the upper floors, and all communication with the east cellar was cut off. This was a sore misfortune, for this apartment was the only possible base of successful tunnel operations. Colonel Rose now began to study other practicable means of escape, and spent night after night examining the posts and watching the movements of the sentinels on the four sides of Libby. One very dark night, during a howling storm, Rose again, unexpectedly met Hamilton in a place where no prisoner could reasonably be looked for at such an hour. For an instant the impenetrable darkness made it impossible for either to determine whether he had met a friend or foe: neither had a weapon, yet each involuntarily felt for one, and each made ready to spring at the other's throat, when a flash of lightning revealed their identity. The two men had availed themselves of the darkness of the night and the roar of the storm to attempt an escape from a window of the upper west room to a platform that ran along the west outer wall of the prison, from which they hoped to reach the ground and elude the sentinels, whom they conjectured would be crouched in the shelter of some doorway or other partial refuge that might be available; but so vivid and frequent were the lightning flashes that the attempt was seen to be extremely hazardous.
Rose now spoke of the entrance from the south-side street to the middle cellar, having frequently noticed the entrance and exit of workmen at that point, and expressed his belief that if an entrance could be effected to this cellar it would afford them the only chance of slipping past the sentinels.
He hunted up a bit of pine-wood which he whittled into a sort of wedge, and the two men went down into the dark, vacant kitchen directly over this cellar. With the wedge Rose pried a floor-board out of its place, and made an opening large enough to let himself through. He had never been in this middle cellar, and was wholly ignorant of its contents or whether it was occupied by Confederates or workmen; but as he had made no noise, and the place was in profound darkness, he decided to go down and reconnoiter.
He wrenched off one of the long boards that formed a table-seat in the kitchen, and found that it was long enough to touch the cellar base and protrude a foot or so above the kitchen floor. By this means he easily descended, leaving Hamilton to keep watch above.