And Tim remembered their name. "Oulopholites," he said. "Sulphate of magnesia and gypsum. Mother Nature does repeat herself, you see. She uses the same forms, but these are lifeless mimicry." And he looked at his watch. "Guess we'd better turn back, eh, skipper? We've been two hours on the prowl, and there doesn't seem to be anything in this direction. Shall we go back and try another corridor?"
Lane nodded slowly.
"I suppose so. But—Oh, while we're this far, we might as well peek into that next cavern. Won't take but a minute. And if there's nothing there—"
The words died on his lips. As he spoke them, they had moved through a short archway; the yellow circle of his flashlight had swung about a cavern larger than any in which they had yet stood. The floor of this cavern sloped sharply
