"The radite lies in a niche in the side of the cliff, just ahead,” he said heavily to the Planeteers. “We must be careful now, for there are almost sure to be some of my poor fellow sufferers near it, bathing in its rays."
"I hope not,” Gunner Welk muttered. “If these radioactive men can't be killed, they'd be tough customers."
They moved on, Nison and the glowing Martian leading, going more slowly and cautiously now.
As they rounded a turn in the crooked chasm, they saw ahead a place where the sand had been beaten down by many feet, over a long time. There was a small natural niche in the chasm wall there-but there was no radite in it.
"The radite's gone!” cried Clymer Nison in amazement, staring unbelievingly at the empty niche in the rock.
"Gone?” exclaimed John Thorn. His heart sank with despair. “Then Cheerly has been here ahead of us. He's taken the radite, and—"
"Listen!” Sual Av cried, turning his helmeted head sharply. “Hear that?"
"They heard, then. A dim uproar of raging voices from farther along the chasm, punctuated every few moments by the rumbling thunder and crash of great rocks falling.
"What can it be?” Nison wondered, his radiant face perplexed.
"I have an idea what it is!” Thorn cried. “Come on!"