precious than his own, he contented himself thenceforth with groaning
in quiet.

The time went on and all attempts to force the door or get through
the wall proved fruitless. What the wall was made of was impossible
to say. It was not metal; it was not wood; it was not stone, And all
the cell seemed to be made of the same stuff. When they stamped on
the floor it gave a peculiar sound that Uncle Prudent found it
difficult to describe; the floor seemed to sound hollow, as if it was
not resting directly on the ground of the clearing. And the
inexplicable f-r-r-r-r seemed to sweep along below it. All of which
was rather alarming.

"Uncle Prudent," said Phil Evans.

"Well?"

"Do you think our prison has been moved at all?"

"Not that I know of."

"Because when we were first caught I distinctly remember the fresh
fragrance of the grass and the resinous odor of the park trees. While
now, when I take in a good sniff of the air, it seems as though all
that had gone."

"So it has."

"Why?"