"But you said that once more it was stationary."
"Yes, and that is the very thing that proves, I believe, the nature of the crack."
"I don't follow you."
"Why it isn't a crack at all, Bob. It is an earthquake fault."
"Good heavens, you don't mean—"
"Yes, I do. I mean that the next time the land slips our little tube will be twisted up like a piece of string, or crushed like an eggshell. That always was a rocky bit of land. I thought in going that far north, though, that we had missed the main line of activity; I mean the disturbances that had once wiped out a whole nation, if your scientists are correct."
"Then you mean that it is only a matter of time?"
"Yes, and I have been informed by one expert that the old volcanic activity is not dead either."
"So that is what has stolen away your laugh?"
"Well I am one of the engineers—and they won't suspend the service."