They reached the tumbled rocks, and stopped. And now the fire-fountain was so lofty that they had to lean back their heads to look at its topmost crest. Some unthinkable diastole and systole of the fiery planet was at work, and this periodic geyser of flame was its result. The rocks shook and roared, and the fires raged higher, and Kellard thought again, what devil is in the blood of our race that drives us to places like this where we should not be?
"I told you," he said to Halfrich, "Just a blowhole, that's all."
"The blips on the record moved," said Halfrich. "There was more than this."
"Look around you!" cried Kellard desperately. "Do you see anything moving, anything that could move? You were wrong, Halfrich. Do you have to keep us here until we all die, because you can't admit you're wrong?"
Halfrich hesitated. "I wasn't wrong. You're still lying. But we'll go back to the ship and wait."
They turned their backs on the fire-fountain, and Kellard felt the sweat pouring on his forehead. It hadn't happened this time, and they couldn't wait forever, they would have to go away and—