His adventure for the night appeared to have ended, for he climbed into bed the following morning without having been disturbed, but lay awake for an hour or more--obsessed with the idea that he really held the clue to the whole affair, but unable to figure out just what it was. Where was it that they intended to place the bomb? Why would they arrange it so as to explode upon pressure, rather than concussion or by a time fuse? Where was Conner's? Who was the man they were plotting against? These were some of the questions which raced through his brain, and he awoke in the late afternoon still haunted by the thought that he really ought to know more than he did. That night at dinner he noted, almost subconsciously, that he was served by a new waiter, a fact that rather annoyed him because he had been particularly pleased at the service rendered by the other man. "Where's Felix?" he inquired, as the new attendant brought his soup. "He isn't on to-night, sir," was the reply. "He had an accident and won't be here for a couple of days." "An accident?" "Yes, sir," was the laconic answer. "Anything serious?" "No, sir. He--he hurt his hand," and the waiter disappeared without another word. Carroll thought nothing more of it at the time, but later, over his coffee and a good cigar, a sudden idea struck him. Could it be that Felix was one of the men whom he had surprised the night before, the one he had fired at and hit? No, that was too much of a coincidence. But then Felix was manifestly of foreign origin, and, while he claimed to be Swiss, there was a distinct Teutonic rasp to his words upon occasion. Signaling to his waiter, Dave inquired whether he knew where Felix lived. "I'd like to know if there is anything that I can do for him," he gave as his reason for asking. "I haven't the slightest idea," came the answer, and Carroll was aware that the man was lying, for his demeanor was sullen rather than subservient and the customary "sir" was noticeable by its absence. Once in the lobby, Dave noticed that the pretty telephone operator was again at the switchboard, and the idea occurred to him that he might find out Felix's address from the hotel manager or head waiter. "I understand that my waiter has been hurt in an accident," the operative explained to the goddess of the wires, "and I'd like to find out where he lives. Who would be likely to know?" "The head waiter ought to be able to tell you," was the reply, accompanied by the flash of what Carroll swore to be the whitest teeth he had ever seen. "Just a moment and I will get him on the wire for you." Then, after a pause, "Booth Number Five, please."