“Where?” asked the others, crowding forward to look closer.  Tom set down the lantern and picked up a broken spade.  There was a cavity in the wall of this pocket-like passage.  With a flourish Tom dug the broken blade of the spade into the gritty earth.

“This is what Jerry wanted that mattock for, I bet!” he exclaimed.

“Oh, dear, me! do you believe so?” cried Ruth.  “Then, right here, is where he thought he might find his uncle’s treasure box.”

“Ho, ho!” ejaculated Ralph.  “That old hunter was just as crazy as he could be—­father says so.”

“Well, that wouldn’t keep him from having money; would it?—­and might be a very good reason for his burying it.”

“And the papers he declared would prove his title to a part of this island,” Ruth hastened to add.

That didn’t please Ralph any too well.  “My father owns the island, and don’t you forget it!” he declared.

“Well, we don’t have to quarrel about it,” snapped Tom, rather disgusted with the way Ralph was behaving.  “Come on! we might as well go back.  But here’s one blow for liberty!” and he laughed and flung the spade forward with all his strength.

Jerry Sheming had never suspected it, or he would not have left the excavation just as he had.  There was but a thin shell beyond where he had been digging, and the spade in Tom’s hand went clear through.

“For the goodness gracious grannies!” gasped Tom, scrambling off his knees.  “I—­I came near losing that spade altogether.”

There was a fall of earth beyond the hole.  They heard it rolling and tumbling down a sharp descent.

“Hold the lantern here, Ruth!” cried Tom, trying to peer into the opening.

Ruth did so.  The rays revealed a hole, big enough for a man to creep through.  It gave entrance, it seemed, to another cavern—­and one of good size.

“Oh, my dear!” exclaimed Ruth, seizing Tom’s arm.  “I just know what this means.”

“You may. I don’t,” laughed Tom Cameron.

“Why, this other cavern is the one that was buried under the landslide.  Jerry said he knew about where it was, and he’s been trying to dig into it.”

“Oh, yes; there was a landslide on this side of the cliff just about the time father was negotiating for the purchase of the island last summer,” said Ralph.  “We all came up here to look at the place a while afterward.  We camped in a tent about where the lodge now stands.  That old crazy hunter had just been taken away from here.  They say he tried to kill Blent.”

“And maybe he had good reason,” said Tom.  “Blent is without a doubt a pretty mean proposition.”

“Just the same, the island is my father’s,” declared Ralph, with confidence.  “He bought it, right enough.”

“All right.  But you think, Ruth, that perhaps it was in this buried cave that old Mr. Tilton hid his money box?”

“So Jerry said.  It looks as though Jerry had been digging here——­”