On one side of the room there stood a magnificent old-fashioned carved mantel-piece. The artistic beauty of the structure did not seem to strike Sturgis; but he appeared to derive a great deal of satisfaction from an inspection of the large tiled hearth. Presently, removing his coat and his cuffs, he plunged his hand into the grimy chimney and removed a handful of soot, which he examined carefully and then threw away. He repeated the operation again and again; until at last, with evident satisfaction, he picked out a small object, which he deposited in an envelope. Then, after washing his hands in the clerks' room, he passed into the cashier's department. In a corner stood the telephone closet, the door of which was open. The receiver of the instrument was down. The reporter took it up and gazed at it long and earnestly. Sturgis's examination of the bank must have lasted over two hours. At first Richard Dunlap looked on with a mild curiosity, in which amusement struggled with good-natured skepticism. But, as time wore on, the banker began to show signs of impatience; and when at last Sturgis returned to the private office and carefully deposited upon a sheet of white paper a miscellaneous assortment of tiny scraps and shreds, the banker could scarcely conceal his dissatisfaction. "Well, Mr. Sturgis," he said, "I hope you have nearly completed your investigation; for my leisure is not so abundant that I can afford to waste it like this." "I need one more witness at least," replied the reporter, "and I am afraid I shall have to ask you to help me obtain it." "But," he quickly added as he noted Dunlap's impatient gesture, "I think I can promise you that the time you are regretting has not been wasted." The financier did not seem convinced by this assertion; but he nevertheless consented with unwilling grace to assist the reporter to the best of his ability. "Well, then," said Sturgis, "tell me, first of all, whether you keep any fire-arms in the bank." "Yes," replied Dunlap; "the cashier has a small revolver which he keeps in his desk, as a means of defence in case of a sudden attack by a bank thief." "Have you a key to the desk?" "Yes," replied the banker. "Will you kindly see if the revolver you mention is in its place?" "It ought to be," said Dunlap, picking out the key on a bunch which he took from his pocket, and walking towards the cashier's department with Sturgis at his heels. "Yes, here it is in its accustomed place." He handed the weapon to the reporter, who examined it attentively. "Exactly," said Sturgis, with satisfaction; "this is what I was looking for." "What do you mean?" asked Dunlap. "I mean that this is the revolver which was fired twice last night in the Knickerbocker bank. See for yourself; two of the cartridges are empty, and the weapon has not been cleaned since these shots were fired." "But who can have fired the pistol, and at whom was it fired, and why?"