e and then another.

The last turned back, he saw another opening, evidently leading upward.

"This must lead to the open air--" he began, when a grinding of stone
caught his ears. In a twinkle a veritable shower of rocks came down
around his head. He was knocked flat and almost covered.

For fully ten minutes he lay gasping for breath. The blood was flowing
from a wound on his cheek, and it was a wonder that he had not been
killed.

"In the future I'll have more care," he groaned, as, throwing first one
stone and then another aside, he sat up. The falling of the stones had
been followed by some dirt, and now a regular landslide came after,
burying him up to the armpits.

"Planted," was the single word which issued from his lips. He was not
seriously hurt, and was half inclined to laugh at his predicament.
Still, on the whole, it was no laughing matter, and Pawnee Brown lost no
time in trying to dig himself free.

The stones and dirt were wedged tightly about his legs, and not wishing
to run the risk of a broken or twisted ankle, the scout worked with
care, all the time wondering if Dick Arbuckle was back, and never once
dreaming of the peril the poor lad was encountering. The rain was
soaking through the ceiling of the cavern, and the situation was far
from a comfortable one.

At last he was free again, and striking a match, he hunted up the
lantern and lit it once more.

The opening to the inner cave was now large enough to pass through with
ease, and making sure of his footing, the scout moved forward, straining
his eyes eagerly for some sign of an egress to the outer world.

Presently he saw a number of straggly things dangling downward from the
rocks and soil overhead.

They were the bottom roots of some great tree standing fifteen or twenty
feet above.

"Not far from the surface now, that's certain," he thought, with
considerable satisfaction. "And yet, hang me if I can see an opening of
any sort yet."

On and on he went, until nearly a hundred feet more had been passed.

The cave had widened out, but now it narrowed once again to less than a
dozen feet. The roof, too, sloped downward until it occasionally scraped
the crown of his sombrero.

The light of the lantern began to splutter and flare up, showing that
the oil in the cup was running low.

"If only the thing lasts until I find the door to this confounded
prison," he thought.

Suddenly a peculiar hiss sounded out upon the darkness.

Pa