"I should think not. If some of us were paid by the idea we'd be pretty poor, but the perspiration part of genius is open to all of us."
"You mean I should charge a bonus for getting this call through?" retorted the operator.
Whatever Burkett's reply to this might have been was never learned; her attention was diverted at that point.
"We've just come in sight of the flow. It's about five hundred yards ahead. We'll get as close as seems safe, and I'll try to make sure whether it's really lava or just mud."
"Mud? Is that possible? I thought there wasn't—couldn't be—any water on this planet!"
"It is, and there probably isn't. The liquid phase of mud doesn't have to be water, even though it usually is on Earth. Here, for example, it might conceivably be sulfur."
"But if it's just mud, it wouldn't hurt the ship, would it?"
"Probably not."
"Then why all this fuss about getting the tractors back in a hurry?"