They have already set a world record for time trapped underground after a cave-in.
Perhaps, after all, he had been on the other side of the cave-in and had hurried on out of the mine.
At any moment might come disaster in the shape of a cave-in or a falling tree.
Maybe he can make up for the time they lost digging out the cave-in if it stays clear and the creeks don't rise any higher.
If he could force a way through the cave-in there might be safety beyond.
Day after day of labor and the indentation upon the cave-in grew from a matter of feet to one of yards.
He attacked the cave-in with the cool energy that characterized him.
They quickly dressed and hiked down the long tunnel to the point they had reached when the cave-in occurred.
"There must have been a cave-in at our gold mine," said Hal.
If there was a cave-in the whole party would disappear in the depths.