The sparkling sheen of the metal cylinder had changed from silver to pale green. The cloud that enveloped it was not heavy, but it was always the same. Yet still Chet insisted: "It may not last."
"Sorry to disappoint you," replied Kreiss, "but there is little ground for such a belief." Again he was the professor instructing a class. "These fumeroles, in my opinion, are venting a region far below the surface. It is possible that further seismic disturbances may alter conditions; a rearrangement of the lower rock strata may close existing crevices and open others like this you have seen; but, barring that, I see no reason for thinking that this emission of what appears to be chlorine with other gases may not continue indefinitely."
Chet looked at Diane. Was it a twinkle that appeared and vanished in her eyes as Herr Professor Kreiss concluded his remarks. She would laugh in the very face of death, Chet realized, but her tone was entirely serious as she offered another suggestion.
"If this wind should change," she said, "and if it blew the gas in another direction, the ship could be cleared. One of us could go in long enough to switch on the air generators full."
But now it was Chet who shook his head in a negative. "Remember," he told her, "when we were here before? All of the time while Walt was gone for the ship—how did the wind blow then?"
"The same as now," she admitted.
"And it never changed."
"No,"—slowly—"it never changed."
Chet turned to Walt and Kreiss. "That's that," he said shortly. "Any other good ideas in the crowd? Can anyone go through that gas and get to the ship? I'll make a try."