There existed at the Châtelet in Paris a large and long cellar. This cellar was eight feet below the level of the Seine. It had neither windows nor air-holes, its only aperture was the door; men could enter there, air could not. This vault had for ceiling a vault of stone, and for floor ten inches of mud. It was flagged; but the pavement had rotted and cracked under the oozing of the water. Eight feet above the floor, a long and massive beam traversed this subterranean excavation from side to side; from this beam hung, at short distances apart, chains three feet long, and at the end of these chains there were rings for the neck. In this vault, men who had been condemned to the galleys were incarcerated until the day of their departure for Toulon. They were thrust under this beam, where each one found his fetters swinging in the darkness and waiting for him.