rove
their canoes up and down the lake, having a fine time every hour of
the day.

Mrs. Morse got on famously with her book, and allowed the girls to do
about as they liked. They got into no mischief, however; but they all
grew brown, and strong, and even Lily began to put on flesh.

At this season there were few fishermen at Lake Dunkirk. Some days
there were long processions of barges sailing past the island, making
for Rocky River and the ports down stream. And sometimes puffy tugs
drew other barges westward, against the current.

None of the crews of these boats disturbed the campers. Acorn Island
had been placarded for years, and it had always been necessary to get
a permit to have even a picnic there.

Just one couple of fishermen came within range of the girls' vision
that first week or ten days. And that couple, in their clumsy canoe,
were never near enough for the girls of Central High to see their
faces.

"I wonder where _they_ camp at night?" said Laura thoughtfully one
evening as she and Jess were paddling in for supper, being the last of
the scattered girls to make camp. She had sighted the strange
fishermen off the western end of Acorn Island again.

"Bet they are the fellows who took our food!" exclaimed Jess,
suddenly.

"And have hung about here all this time? Nonsense!" returned Laura.
"But don't let Lil and Nellie hear you say that."

"All right. But I bet they are."

"I'm more worried by that cloud yonder," said Laura. "We're going to
have a tempest."

"Hope not till supper's over," said the hungry Jess.

"We'll peg down the tents to make sure as soon as we get in," said the
careful Laura.

They did so. Half through supper the first drops of the storm fell.
Then the thunder rolled nearer and a tall tree was riven on the
mainland, within sight of Camp Acorn.

_That_ pretty well settled the supper for most of the girls. Even the
bravest had never experienced a thunder storm under canvas before.

So they all ran into Mrs. Morse's cabin. It did not seem so bad
there.

In the midst of the downpour, however, and in a lull between thunder
claps, Barnacle, who had been tied to the corner of the hut and had
crawled under the floor for protection, suddenly broke out with a
terrific salvo of barks. He rushed out into the rain and leaped at the
end of his rope, barking and yelping.

"Somebody's about the camp," murmured Mrs. Morse. "The dog's nose--if
not his eyes--tells him so."

"It's L