The tunnel enterprise was the project of a few choice spirits only.  It was too perilous to confide to many.  The disused cellar was chosen as the avenue of escape.  It was never visited, and might be used with safety.  But how to get there was a difficult question to solve.  And how to hide the fact that men were absent from roll-call was another.  The latter difficulty was got over by several expedients.  If Lieutenant Jones, for instance, was at work in the tunnel, Captain Smith would answer for him; then, when Smith was pronounced absent, he would step forward and declare that he had answered to his own name.  His presence served as sure proof that he had not been absent.  Other and still more ingenious methods were at times adopted, and the authorities were completely hoodwinked in this particular.

And now as regards the difficulty of entering the cellar.  The cooking-room on the first floor contained, in its thick brick and stone partition, a fireplace, in front of which, partly masking it, three stoves were placed for the cooking operations of the prisoners.  The floor of this fireplace was chosen as the initial point of excavation, from which a sloping passage might be made, under the floor of the next room, into the disused cellar.

Captain Hamilton, a stonemason by trade, began the excavation, removing the first brick and stone from the fireplace.  It need scarcely be said that this work was done only at night, and with as little noise as possible.  By day the opening was carefully closed, the bricks and stones being so ingeniously replaced that no signs of disturbance appeared.  Thick as the wall was, a passage was quickly made through it, presenting an easy route to the cellar below.  As for this cellar, it was dark, rarely or never opened, and contained only some old boxes, boards, straw, and the like d[’e]bris, and an abundance of rats.

The cellar reached, and the route to it carefully concealed by day alike from the prison authorities and the prisoners not in the secret, the question of the tunnel followed.  There were two possible routes.  One of these led southward, towards the canal; the other eastward, under a narrow street, on the opposite side of which was a yard and stable, with a high board fence on the street side.  The opposite side of the yard faced a warehouse.

A tunnel was commenced towards the canal.  But it quickly struck a sewer whose odor was more than the workers could endure.  It was abandoned, and a tunnel begun eastward, the most difficult part of it being to make an opening in the thick foundation wall.  The hope of liberty, however, will bear man up through the most exhausting labors, and this fatiguing task was at length successfully performed.  The remainder of the excavation was through earth, and was easier, though much the reverse of easy.