r
fear of slipping down.

Suddenly a number of bats flew out of a hole nearby, dashing against
the torches and against the boys themselves. The rush was so unexpected
that each youth dropped his light and put up his hands to protect
himself.

"Get out! Let me alone!" spluttered Sam.

"Whoop!" roared Tom. "Confound the bats anyway! Get along and let us
alone!"

Lying on the flooring the torches soon went out, and in their efforts
to protect themselves from the bats the boys rushed blindly down the
passageway. Then of a sudden both slipped on the wet rocks, slid a
distance of several yards, and went down and down, landing into a
well-like opening with a loud splash!

CHAPTER XXVI

THE CAVE ON THE ISLAND

"Tom!"

"Sam!"

"Are you safe?"

"Yes, but I wasn't looking for such a cold bath as this."

"I guess we must have fallen into a regular well of spring water."

"Never mind what we are in. The question is, how are we to get out?"

"Can you touch the top of the opening?"

"No."

"Neither can I."

Luckily the two boys could touch the bottom of the hole, so they were
in no danger of drowning. They were in water up to their waists and
calculated they had dropped a distance of two or three yards. All
was pitch dark around them and as silent as a tomb, save for some
water which trickled close at hand. The bats had departed, leaving
them to their fate.

"This is cave-investigating with a vengeance," said Tom, with something
like a shiver.

"Never mind, Tom, we won't die of thirst anyway."

"Do you think this is a laughing matter, Sam?"

"No, I don't. I'd give a good deal to be out of this hole and out of
the cave also."

"I've got an idea. Let me climb on your shoulders and see if I can
reach the top that way."

Sam was willing, and soon Tom was balancing himself as best he could.
He felt around with care, Sam moving from point to point as directed.

"Here is a sharp rock; I think I can pull myself up on that," said
Tom. He tried with all of his strength and went up off Sam's shoulders.
Then the youngest Rover heard him crawling around the wet flooring
carefully.

When Tom felt fairly safe he brought out his waterproof match safe
and lit a match. Then one of the torches was picked up and he lit
that, but kept it partly sheltered, fearing another attack from the
bats.

By the aid of the torch, Sam was able to reach a sharp rock quite
low down in the well hole, and when Tom gave him a h