d!" suddenly exclaimed Grace. "Let's see if we can't find a
place to sit down."

"Tired! No wonder, wearing such high-heeled shoes!" objected Betty. "You
are violating one of the ethics of the outdoor girls' organization!" she
went on. "You can't expect to walk in those."

"I'm not going to try again," confessed Grace. "Oh, I simply must sit
down."

"The sand is so wet," objected Mollie.

They managed to find a broken spar, cast up by the waves, and by putting
on it some boards, which they turned over to find the dry side, they
evolved a comfortable seat.

"Oh, isn't this just lovely!" exclaimed Betty, as she gazed out over the
bay, now glistening beneath the sun, which had come out from behind the
storm clouds.

"It is perfect," agreed Amy.

Mollie was idly digging in the sand behind the spar. She used a shell,
and had scooped out quite a hole. Suddenly the shell scraped on
something with a shrill sound.

"Oh, don't!" begged Grace. "You set my teeth on edge! What is it,
Mollie?"

Mollie did not answer at once. She was digging in the sand more quickly
now. Again the shell scraped on some metal.

"Oh, Mollie!" objected Grace again, putting her hands over her ears.
"What is it?"

"I--I think I've found something," replied Mollie in a low voice. "Look,
girls, it's some sort of box."

They leaned over her. Her shell had scraped away the wet sand from the
top of a square piece of metal. Mollie tapped it.

"It--it sounds hollow!" she whispered.

"Probably a tin can," said Betty.

"No," spoke Mollie, resolutely.

"Here, let me help you!" exclaimed Amy.

She looked about for something with which to dig. Near where Mollie had
uncovered the piece of metal a queerly shaped stick stuck upright in the
sand. Amy pulled it out, with no small effort, and at once began
digging.

"Oh, it's some sort of a box--an iron box!" cried Mollie, with eager,
shining eyes. "We have really found something."

Mollie and Amy dug until they had wholly uncovered the object. Then,
with a quick motion, Mollie put her hands under the lower edges, and
with a sudden effort brought up out of the hole in the sand a curious
iron box.

"It--it really is--something!" she said.

Instinctively Betty looked out over the bay in the direction taken by
the strange, quarreling men in the motor boat.

CHAPTER X

CONJECTURES

Mollie Billette set the black iron box down on the log that had formed
the seat for the outdoor girls. A