We were now two levels below the roof, and at the point where we were to separate. I did not want to let Wilma out of my sight, but it was necessary. According to our plan, Barker was to make his way to the projectoscope plant, Blash and I to the library, and Wilma and Gaunt to the military office. Blash and I traversed a long corridor, and paused at the great arched doorway of the library. Cautiously we peered in. Seated at three great switchboards were library operatives. Occasionally one of them would reach lazily for a lever, or sleepily push a button, as little numbered lights winked on and off. They were answering calls for electrograph and viewplate records on all sorts of subjects from all sections of the city. I apprised my companions of the situation. "Better wait a bit," Blash added. "The calls will lessen shortly." Wilma reported an officer in the military office sound asleep. "Give him the can, then," I said. Barker was to do nothing more than keep watch in the projectoscope plant, and a few moments later he reported himself well concealed, with a splendid view of the floor. "I think we can take a chance now," Blash said to me, and at my nod, he opened the lid of his dope can. Of course, the fumes did not affect us, through our helmets. They were absolutely without odor or visibility, and in a few seconds the librarians were unconscious. We stepped into the room. There ensued considerable cautious observation and experiment on the part of Gaunt, working from the military office, and Blash in the library; while Wilma and I, with drawn swords and sharply attuned microphones, stood guard, and occasionally patrolled nearby corridors. "I hear something approaching," Wilma said after a bit, with excitement in her voice. "It's a soft, gliding sound." "That's an elevator somewhere," Barker cut in from the projectoscope floor. "Can you locate it? I can't hear it." "It's to the east of me," she replied. "And to my west," said I, faintly catching it. "It's between us, Wilma, and nearer you than me. Be careful. Have you got any information yet, Blash and Gaunt?" "Getting it now," one of them replied. "Give us two minutes more." "Keep at it then," I said. "We'll guard." The soft, gliding sound ceased. "I think it's very close to me," Wilma almost whispered. "Come closer, Tony. I have a feeling something is going to happen. I've never known my nerves to get taut like this without reason." In some alarm, I launched myself down the corridor in a great leap toward the intersection whence I knew I could see her.