the light he'll be able to locate himself,"
said Fred.

The boys took a walk around by the boat landing, and also to the edge of
the woods back of the cabin, but all to no purpose. Then they finally
retired to their own shelter.

"We might as well go to bed," suggested Handy. "It won't do any good for
all of us to stay up. If you say so, we might take turns in staying on
guard, in case we should hear a call for help, or anything like that."

This was considered good advice, and each youth took two hours at
staying awake while the others slept; and thus the night passed.

With the first streak of daylight, the boys prepared a hasty breakfast,
and then went outside to view the situation. They soon found the tracks
of the old lumberman's snowshoes, leading into the woods, and presently
saw two other tracks close behind them.

"I'm no sleuth, but it looks to me as if Uncle Barney went into the
woods and two persons followed him!" exclaimed Jack.

"Just the way it looks to me, too," answered Fred.

"Let's go and follow up those footprints at once," suggested Andy.

The others were willing, and in a short space of time they were on their
snowshoes and making their way through the woods in the center of the
island.

"Hello! here's something!" cried Jack presently, and pointed to the old
lumberman's snowshoes, where they still rested among the branches of a
tree.

Then the boys saw where he had climbed between the rocks, and, taking
off their snowshoes, they followed the footprints.

"A cave!"

"What do you know about that!"

It did not take the lads long to reach the entrance of the cavern. Then
Jack, who had brought along one of the flashlights, turned it on and
entered, followed by his cousins.

"Hello, Uncle Barney!" he cried out at the top of his lungs. "Uncle
Barney! are you here?"

"Help! help!" came feebly from the inner end of the cave, and, guided by
the flashlight, the four Rovers ran in that direction. They found the
old man sitting on a rock with his head resting on his arm.

"Are you hurt? How did it happen?" questioned Jack quickly.

"They've robbed me!" moaned the old lumberman. "They came up behind me,
and somebody hit me in the head with a rock! Then they ran away with my
tin box!"

"Who was it? Are you badly hurt?" questioned Randy.

"I guess I'm not so awfully bad off, even though my head did bleed
some," answered Uncle Barney. "But the worst of it is, they got away
with my tin box--