He made the rounds along one side of the corridor and started back on the side opposite his own office. The night lights were on and at the far end of the corridor it was necessary for him to use the flashlight.

Door after door proved unyielding to his touch and he was about to give up the quest when he came upon a door that swung inward when his hands gripped the knob.

Bob drew back suddenly and flashed the beam of light into the long room, which was almost identical with the one in which he had been working. What he saw there startled him more than he dared to admit later, and he stepped inside and moved toward the nearest desk.

The ray from the flashlight revealed the utter confusion in the room. Baskets of papers on top of the desks had been upset and even the drawers in the filing cabinets had been pulled out and their contents hurled indiscriminately over the floor.

A slight sound startled Bob and he swung around, the beam of light focusing on the door.

It was closing—swiftly and silently.

Bob leaped forward, stumbled over a wastepaper basket, and then reached the door which clicked shut just before he could grasp the handle.

Bob tugged hard on the door, but like the one which led to his own office, it stuck.

Could it be another wedge of steel? Bob wondered and braced himself for another lusty tug. The door gave way and Bob toppled backward in a heap, the flashlight falling and blinking out.

Bob had fallen heavily and for a moment he remained motionless on the floor listening for the sound of someone moving along the corridor. He could have shouted for the guard, but an inward distrust of the man kept him from doing that. Instead, he groped around for the flashlight, turned it on, and got to his feet, considerably shaken in mind and body by the experiences of the last few minutes.