Chapter V A SLIVER OF STEEL ★ The time seemed endless. Actually it could only have been seconds that Bob sat there watching the turning of the doorknob. Then the knob started back. Unseen fingers had learned what they wanted to know. The door was not locked. Through the hulking building there seemed no sound except Bob’s own strained breathing. In the corridor it was as quiet as in the room, yet someone must be outside the door, testing the lock. Bob shook his head. He must be dreaming. His nerves must be over-wrought from too much work and on edge from the talk he had earlier in the evening with his uncle. Reaching out, he tilted the shade of his desk lamp back and a flood of light struck the doorknob. No! His eyes had not tricked him. The knob was still turning. There was a faint click and then the knob remained stationary. Bob leaped into action. In one fast lunge he was across the room, his hands gripping the doorknob. He tugged hard, but the door refused to open. Then he paused for hurried footsteps were going down the hall. Bob shouted lustily. Perhaps his cry would reach the guard at the elevators. Then he shook the door. It couldn’t be locked, of that he felt sure. Bracing himself again he tugged at the door and almost fell over backwards when it suddenly opened. Bob stepped into the corridor. There was no one in sight but from a distance he could hear someone hurrying toward him. A guard came around a turn in the corridor. “Did you call just then?” demanded the watchman. “I’ll say I did,” replied Bob. “Someone was trying the door here and when I tried to open it, the door stuck. Then I let out a whoop. Didn’t you see anyone?” “No one came my way,” said the guard quickly, but his eyes did not meet Bob’s squarely. “We’d better look along this end of the corridor. If someone was here, he might have slipped into one of the other offices.” Bob shook his head. “No, he wouldn’t have done that. Besides, I distinctly remember hearing him running down toward the elevators.” “Well, I wasn’t asleep and no one came my way,” insisted the guard. “Maybe you were dreaming a little. You look kind of tired.” “I am tired, but this was no dream,” insisted Bob. Then he remembered the door. What had made it stick? It hadn’t been locked. “Give me your flashlight,” said Bob and the guard handed over a shiny, metal tube. Bob turned the beam of light on the floor, and searched closely. “What are you looking for?” asked the guard. “For the reason why the door stuck,” said Bob tartly. Then he found it—a thin sliver of steel that had been inserted as a wedge. It was an innocent enough looking piece, but when placed properly in a door could cause considerable delay.