About ten o’clock
He listened attentively , and the whispered words , `` He has gone to bed , '' said by the old woman , reached his ear . By an accident unknown probably to the architect , the slightest noise on the staircase sounded in the room of the apprentices , so that Philippe did not lose a single movement of the miser and his sister who were watching him . He undressed , lay down , pretended to sleep , and employed the time during which the pair remained on the staircase , in seeking means to get from his prison to the hotel de Poitiers . About ten o'clock Cornelius and his sister , convinced that their new inmate was sleeping , retired to their rooms . The young man studied carefully the sounds they made in doing so , and thought he could recognize the position of their apartments ; they must , he believed , occupy the whole second floor . Like all the houses of that period , this floor was next below the roof , from which its windows projected , adorned with spandrel tops that were richly sculptured . The roof itself was edged with a sort of balustrade , concealing the gutters for the rain water which gargoyles in the form of crocodile 's heads discharged into the street .