they came on swiftly over the blue waters.

"Are they in the boat?" asked Grace.

"Who?" Mollie wanted to know.

"Betty and Amy."

"Why, how could they be?"

"I thought perhaps the boys might have come up while we were asleep,
taken Betty and Amy out for a little run, and were now coming back, to
laugh at us for being so lazy."

"Well, they're not in the motor boat, anyhow," Mollie said. "I do hope
nothing has happened."

Grace did not ask what might possibly have happened. She was just a
little afraid of what her chum might say. The sprained ankle theory was
too simple. Somehow Grace felt a growing concern.

But, for the present, at least, this was lost sight of in the little
excitement over the advent of the boys. They came on, laughing, singing
and shouting, while Roy held up a string of fish. Evidently they had had
good luck.

The motor boat grounded gently in the shallow water and the boys jumped
out, Allen tossing out a light anchor high up on the sand.

"We came to take you home," he announced. "We thought you'd have enough
of picnic by this time. Where's Betty?" he asked, quite frankly. Allen
was not at all fussy about showing his admiration for the Little
Captain.

"Why, it's queer," Mollie replied, smiling just the least bit, "but she
and Amy seem to have gone off by themselves. Grace and I dozed, and when
we awoke they were gone."

"Probably down the beach," suggested Roy. "How's that for fish?" and he
held up the string. But Mollie and Grace were not interested in fish
just then.

"We've been looking for them," Mollie went on. "We were looking
when--when you came."

Something in her words and manner caused Allen to ask quickly:

"You--you don't think anything could have happened; do you?"

"I--I don't know what to think," Mollie faltered. "It seems--a little
strange."

"Oh, we'll find them," declared Henry. "Amy isn't one to go far."

"But Betty is a great walker," Grace ventured.

"Well, we'll find them and all go back in the boat," proposed Allen. "It
looks as though we might have a thunder shower. That's why we gave up
fishing. Come on, have a look."

It did not take a very long search up and down the beach to disclose
the fact that Amy and Betty were nowhere near. The little clump of trees
held no hiding place, and unless they had gone inland there was no other
explanation except that they had gone back to the cottage.

"And this they would hardly do," said Mollie. "Unless som