r. Bird nodded agreement and with a sharp command to his men Bolton broke into a run. Not a shot was fired as they approached, and the front door gave readily to Bolton's touch. At it opened there came a grating sound from the roof followed by the whir of a propeller. Dr. Bird ran out of the building and glanced up.
"A helicopter!" he cried. "They were expecting us and have escaped!"
He drew his pistol and fired ineffectually at the great bird-like ship which was rising almost noiselessly into the air. He cursed and turned again to the building.
Bolton still stood in the room which they had first entered. His flashlight showed it to be empty, but from under a door on the opposite side a line of dull red light glowed evilly. With his pistol ready in his hand, Bolton approached the door on hands and knees. When he reached it he threw his shoulder against it and dropped flat to the floor as the door swung open. No shot greeted him, and he stared for a moment and then rose to his feet.
"Nothing in here but some glass statues," he announced.
Dr. Bird followed him into the room. As he looked at what Bolton had called glass statues he gasped and shielded his eyes.
"God in Heaven!" he ejaculated. "Those were living men!"