For a time there was no sound in the room. He could not even catch the breathing of the other man and he thought of the possibility that the other had slipped out the door before he had closed it. Then he dismissed that as an impossibility for there had not been sufficient time for that. Bob knew every inch of the long office; knew where every desk and chair was located and every window. As his eyes became more accustomed to the dark he could pick out the lighter blots which were the windows. Then a slight noise caught his attention. The unknown was moving, probably on his hands and knees, feeling his way toward the door. Bob couldn’t resist a chuckle as he thought of the dismay that would spread through the other when he found the door securely locked and the key missing. Just to be on the safe side, Bob edged away from the door and sought shelter behind a nearby desk. To make sure that he would move noiselessly he slipped off his shoes and placed them beside a filing cabinet where he wouldn’t fall over them if it was necessary for him to make a sudden move. Strangely enough Bob felt very calm. His heart beat rapidly and his breath came shorter and faster, but his mind was remarkably clear, his hands steady. He was glad now that he did not have the flashlight, for using it would only have made him a target for the marauder. Bob wondered how long it would take his uncle to reach the scene. Probably another ten minutes, for Merritt Hughes lived a considerable distance from the building. What might happen inside that room in the next ten minutes was something that Bob didn’t care to guess about. As Bob listened he could hear the almost noiseless movements of the other man and knew that he was nearing the door. Then he heard hands moving along the woodwork—finally the gentle turning of the doorknob. Then there was the sharp rattle of the knob as though a sudden wave of anger had swept over the man at the realization that he had been trapped in the room. Bob moved away from the door, crawling on his hands and knees, and he kept going until he was well down the room and right at the steel cabinet where the radio documents were filed. With cautious hands he felt along the front of the case. So far the drawers had not been pulled out for they were identified only by key numbers instead of by the name of the type of papers which they contained. This was one cabinet Bob was determined to protect, for, after what his uncle had told him earlier in the night, he felt sure that this was the object of the unknown’s visit. Once more the doorknob was rattled sharply; then silence again shrouded the room and Bob felt his nerves tightening. It was tough waiting alone in the darkness. He wondered if the other man possessed a gun and if he would have the nerve to use it if an emergency caught him.