"That they were ours."

"Ours! I don't see why they aren't!" exclaimed Grace, quickly. "Of course Mollie and Amy dug them up, but----"

"Oh, don't hesitate on my account!" Mollie said, quickly. "If we share at all we share alike, of course."

"That's sweet of you, Billy," returned Betty. "But I don't see how we can keep them. The diamonds, if such they are, must belong----"

"Yes, whom do they belong to?" demanded Mollie. "If you mean the men we saw in the boat, I should say they didn't have any more right to them than we have. They were pirates if ever I saw any."

"Well, you never saw any pirates," remarked Betty, calmly. "But of course the men in the boat may have hidden the diamonds there."

"Do you think they knew they were in the box?" asked Amy.

"Well, whoever hid the box must have known it contained something of value," Betty declared. "They would hardly hide an empty box, and if they had found it locked they would have opened it to make sure there was nothing of value in it. Of course those men may only have been acting for others."

"But what are we to do?" asked Amy.

"We must try to find out to whom these diamonds belong," Betty said.

"We'll have to watch the advertis.e.m.e.nts in the paper, and if we see none we'll advertise for ourselves. That's the law, I believe," and she looked at Allen.

"Yes, the finder of property must make all reasonable efforts to locate the owner," he said, "though of course he could claim compensation for such effort. I think the papers are our best chance for finding clues."

"Has there been a big diamond robbery lately?" asked Mollie.

"What has that to do with it?" Will wanted to know.

"Because I think these diamonds are the proceeds of some robbery," went on the girl. "As you say, the stones are wrapped in a paper just as though they had come from a jewelry store. It might be that those men broke into a store, took the diamonds and hid them in this secret part of the box, which one of them owned. They are probably from some big robbery in New York, or Boston, seeing we're nearer Boston than we are New York, up here."

"I don't remember any such robbery lately," Roy said, and he was a faithful reader of the newspapers. "But of course we've been pretty busy lately. I'll get some back numbers of the papers."

"Ha! What's going on now?" asked the voice of Mr. Nelson. He had come in from the station, having run up to Boston on business.

"Oh, Daddy!" cried Betty. "Such news! You'll never guess!"

"You've solved the cipher!" he hazarded.

"No. We didn't need to. We solved the mystery of the box, and look----"

She spread the sparkling stones out before him.

"Whew!" he whistled. "I should say that _was_ news. Where did you get those?"

"In a hidden compartment of the black box. I stumbled on the secret spring by accident when I was measuring it. Are they diamonds, Father?"

Anxiously the young people hung on Mr. Nelson's answer.

He laid aside the packages he had brought from Boston, and turned for a moment to greet his wife, who had come into the room. She had been told of the find as soon as it was discovered, and had been properly astonished.

"It takes the young folks to do things nowadays," he said, with a smile.

"Doesn't it?" she responded.

"But are they diamonds? That's what we want to know!" chanted Betty, her arms around her father's shoulders.

Mr. Nelson tested the stones much as Allen had done, but he went farther. From his pocket he produced a small but powerful magnifying gla.s.s. It was one he used, sometimes, in looking at samples of carpet at his office. He put one of the larger stones under the gla.s.s.

The young people hardly breathed while the test was going on. But the result was not announced at once, for Mr. Nelson took several of the sparkling stones, and subjected them to the scrutiny under the microscope.

"Well," he announced finally, "I should say they are diamonds, and pretty fine diamonds, too!"

The girls gave little squeals of delight.

"You were right, old man," spoke Henry to Allen, with a nod.

"Well, I wasn't sure, of course" began the young law student "but----"

"Of course I didn't look at all the stones," broke in Mr. Nelson, and the talk was instantly hushed to listen to him, "but I picked several out at random, and made sure of them. And it is fair to a.s.sume in a packet of stones like this that, if one is a diamond, the others are also."

"And how much are they worth?" asked Betty. She was not mercenary, but it did seem the most natural thing to ask.

"Well, it's hard to tell," her father replied. "At a rough guess I should say--oh, put it at fifty thousand dollars."

"Oh!" cried Mollie. "To think of it!"

"Catch me! I'm going to faint!" mocked Roy, leaning up against Will.

"Do you really think they are as valuable as that?" asked Amy, in a gentle voice.

"She helped find them, and she wants to reckon her share," said Mollie, who did not always make the most appropriate remarks.

"Nothing of the sort!" exclaimed Betty. "It's just the wonder of it all."

"I think fifty thousand dollars would be pretty close to the mark," said Mr. Nelson. "I once had to serve on a committee to value the contents of a jewelry store for an estate. I didn't know much about precious stones, but the others gave me some points, and I remember them. Of course I may be several thousands out of the way, but----"

"Oh, fifty thousand dollars is a nice enough sum--to dream about," Betty said, with a gurgling laugh. "It will do very well, Daddy dear."

"But isn't it the most wonderful thing, that we should find all those diamonds!" gasped Mollie.

"Who could have hidden them?" wondered Amy.

"That's what we've got to find out," put in Allen. "I suggested the newspapers," he went on to Mr. Nelson.

"And a good idea," that gentleman said.

"Oh, Betty. Let's look at the box, and see how the wonderful false bottom fitted in," proposed Mollie. "I think it was the most perfectly gorgeous thing how you happened to discover it."

"And that's just how it was--a happening," the Little Captain remarked.

"Oh, but if those men in the boat should discover that we have those diamonds, and come for them," and Betty glanced nervously over her shoulder.