nine o'clock
It has been proved to absolute certainty that Cardillac never left the house that night , and so , of course , Olivier 's assertion that he went out with him is an impudent lie . The house door is provided with a ponderous lock , which on locking and unlocking makes a loud grating echoing noise ; moreover , the wings of the door squeak and creak horribly on their hinges , so that , as we have proved by repeated experiments , the noise is heard all the way up to the garrets . Now in the bottom story , and so of course close to the street door , lives old Master Claude Patru and his housekeeper , a person of nearly eighty years of age , but still lively and nimble . Now these two people heard Cardillac come downstairs punctually at nine o'clock that evening , according to his usual practice , and lock and bolt the door with considerable noise , and then go up again , where they further heard him read the evening prayers aloud , and then , to judge by the banging of doors , go to his own sleeping-chamber . Master Claude , like many old people , suffers from sleeplessness ; and that night too he could not close an eye . And so , somewhere about half-past nine it seems , his old housekeeper went into the kitchen -LRB- to get into which she had to cross the passage -RRB- for a light , and then came and sat down at the table beside Master Claude with an old Chronicle , out of which she read ; whilst the old man , following the train of his thoughts , first sat down in his easy-chair , and then stood up again , and paced softly and slowly up and down the room in order to bring on weariness and sleepiness . All remained quiet and still until after midnight .