Ronson rose to his feet, angry. What farce was being perpetrated here? What—The super-sonic note came into hearing. Pain stabbed at his chest.
He lifted his hand involuntarily. The sight of the dial on his wrist watch forced itself through the pulses of pain.
As a part of his research into cell structure, Ronson had worked extensively with radioactivity. In order to protect himself, he had had a microscopically small radiation detector built into the watch itself. Three tiny glow tubes were set into the dial. If the green tube glowed, radiation was present but was safe. If the amber light glowed, be wary. If the red light glowed, get out fast!
The red light was glowing now. As Ronson stared, it winked out. Before he could take his eyes away from the dial, the red light flicked on again. The super-sonic note came with it. A flick of very real pain came with the note. The red light flicked out, the note vanished. The pain was gone.
"Regular pulsations of radiation are being poured through this place!" Ronson whispered.
It was being done deliberately. The whole cavern was being flooded periodically with bursts of radiation. This meant deliberate intention, purpose, plan. He did not know what impact this radiation might have on Martian flesh but he could guess the effect it might have on human tissue.
Fear came up in him, a flood of it. Anger followed it. The lights on his watch danced. Pain, agony, and the shrill note of the super-sonic came again. Grimly, he began to prowl the cavern, searching for the source of the radiations. The radiation counter in his watch led him to it, by the increased intensity of its glow. The radiations were coming from a single spot in the wall of the cavern. So far as he could tell, the wall was solid stone at this place, but he had seen solid stone walls dissolve in this madhouse. Behind this spot there was intelligent direction of the bursts of radiation.
Back there Les Ro, or someone with him, was playing games of life and death with—
Te Hold came past him, screaming. The Martian was beginning to stumble as he ran. The screams were only gasping sounds in his throat.
Voices rose in shouted argument somewhere in the shrubbery. Ronson moved away.