Thomas, the resident porter, did this as usual on Sunday, but no Coulsdon made his appearance. On glancing at one of the clocks, it was found that no visit was registered since two o'clock, and it was evident that something was wrong. The clerks, with Thomas, the porter, went at once to the strong-rooms, and found the ruined door and Coulsdon lying, gagged and unconscious, in the outer safe. Urgent messages were at once dispatched to one of the directors and one of the three general managers, who were known to be in town. "And to-day is Wednesday," said Quarles, with a lift of his eyebrows. "The thieves have a long start. Now for details, Wigan." "The porter, Coulsdon, did not regain consciousness for some hours," I said. "He can tell us little. To reach the strong-rooms you have to descend half a dozen steps, and as he reached the foot of these he received a blow out of the darkness, whether from a weapon or a fist only he cannot say, but the effect was stunning, and he cannot swear what happened afterward. He thinks something was thrown over his head, but he really remembers nothing from the time he was struck to the time he woke up." "An old servant of the bank, you say?" "Yes, but only recently moved to London. He has been porter at the Leamington branch. There is a disposition to suspect Coulsdon," I went on; "and not without reason, seeing that he is a big, hefty man, who might be expected to give a good account of himself. But there is a curious complication. About a month ago a clerk named Frederick Ewing was summarily dismissed. He had been in the bank some years, had risen in the service, and was trusted. He was in the securities department, and had considerable knowledge of the methods used with regard to the strong-rooms. It was discovered through a sudden and unexpected inspection that certain small sums had been taken from the petty cash of this department. Only Ewing had access to this money, and, as a matter of fact, he confessed. He had only borrowed the money temporarily, he said, and pleaded earnestly that drastic measures should not be resorted to. However, since the integrity of a bank official must be above suspicion, he was dismissed at a moment's notice. He was not prosecuted." "What has become of him?" asked Quarles. "I can find no trace of him at all. He had lodgings in Hammersmith. He returned there after his dismissal, remained there until the next day, and then went out, saying he would be away for a couple of nights. He has not returned; nor has a search in his rooms disclosed any clew. He appears to have had no friends and received hardly any letters." Quarles nodded his head thoughtfully for a few moments. "How did the thieves get into the bank?" he asked.