t a
little note of exultation creep into her voice. "At least, that was one
of the purposes for which it was intended."

"And what was the other?" Mollie asked, as she put back a stray lock of
her dark hair, for the wind had blown it about.

"As a mark," said Betty.

"A mark!" exclaimed Amy.

"Yes," went on Betty. "The men who hid the box put the stake in the sand
so they could find their treasure again."

"Oh, then you are sure it _is_ treasure," Mollie returned.

"Well, we might as well think that as anything else--until we get the
box open and find it full of--sand!" declared Betty, laughing.

"Oh, let's open it now!" cried Grace, impulsively. "I'm just dying to
see what's in it. Please let's open it now."

"Perhaps we have no right," objected Amy.

"Why, of _course_ we have," insisted Grace, making "big eyes" at Amy.
"We found it. Can't we open it, Betty?"

But there was a very good reason why the girls could not open the
box--at least then and there.

CHAPTER XI

THE CIPHER

"Locked!" exclaimed Betty, laconically, when she had tried the cover of
the box.

"Oh, dear!" came petulantly from Grace. "Isn't that horrid!"

"Well, I suppose the men have a right to lock up their treasure," coolly
remarked Betty, again vainly trying to raise the cover.

"You will have it that those men hid the box," said Amy, with a smile.
"Also that it is treasure."

"I'm getting romantic--like Grace," commented the Little Captain.

Then, as they found that their efforts to open the box were vain, the
girls looked at it more closely.

It was a black japanned box of tin, or, rather, light sheet iron, rather
heavier than the usual box made for holding legal papers. It was such a
receptacle as would be described, in England, as a "dispatch box." And
in fact, the box did seem to be of some foreign make. It was not like
the light tin affairs used locally to hold deeds, insurance policies and
the like.

The cover fitted on tightly. This much was seen at a glance, and so well
did it fit that it needed a second look to make sure which was the
bottom and which the top, for there was no bulge or "shoulder" of the
metal to indicate where the lid rested.

"It's water-tight, I'm sure," Mollie said, when the box had again been
set upright. They decided that the top was that place where the initials
"B. B. B." showed, half-obliterated, in white paint.

"Then it might have been washed ashore from some wreck," Amy said.