ten o’clock
Knowledge was at hand . Not only would he discover the manner in which his adversaries employed those little openings , which were apparently unemployable , since they did not allow a person to reach the upper bolts , but he would learn who the ingenious and energetic adversaries were with whom he repeatedly and inevitably found himself confronted . One incident annoyed him . In the evening Daubrecq , who had complained of feeling tired at dinner , came home at ten o'clock and , contrary to his usual custom , pushed the bolts of the hall-door . In that case , how would the others be able to carry out their plan and go to Daubrecq 's room ? Lupin waited for an hour after Daubrecq put out his light . Then he went down to the deputy 's study , opened one of the windows ajar and returned to the third floor and fixed his rope-ladder so that , in case of need , he could reach the study without passing though the house .