The smaller boy looked rather wistfully into the hole as Dick went down, and Jack, breaking another stout stick, asked: 

“Do you want to go down there, young fellow, and follow Dick Percival on a fool’s errand?”

“It might not be that,” said the other, “and I would like to go.”

“All right, then, come along.  Here is a staff for you.  I can do without one, I think.  Keep close to me.  Can you walk upright, Dick?”

“Yes, generally,” came back the answer in a muffled voice.  “My! but the place is filled with echoes, Jack.  It goes down quite a distance I should say.  The light is a big help.  Funny, but there seems to be a light down here, although where it comes from I can’t say.”

The boys kept going down and at length Jack said, pausing and trying to pierce the darkness, the light that Percival had spoken of not being visible at that moment: 

“I think we would better get a light, Dick.  We don’t know where we are going, and it is dark.  It is never safe to go anywhere in the dark unless one is familiar with his surroundings.”

“That’s true enough, Jack.  Have you any matches?  The next time we come this way, if we do, we had better take a flashlight along.”

“I have matches,” said Jack, and in a moment a tiny blaze shot up, increasing till it enabled them to see to some extent where they were.

They were still descending, but in a short time were on more level ground or rock, whatever it was, proceeding till the match went out, and a few steps farther when Dick suddenly brought up against something and exclaimed in surprise: 

“Hello! we cannot go any farther, Jack.  Strike another match, and let us see where we are.”

Jack lighted two or three matches at once, and held them just above his head so as to obtain a good view of his surroundings.

“Hello! what is this?” exclaimed Percival.  “A cave, or what?”

Just before them was a jagged opening into some region beyond, but whether it was a cave or not puzzled them.

Jack went closer, and held his light in the jagged opening.

“It’s a hole in the side of a vessel, Dick!” he cried in amazement.

CHAPTER VI

A WALK UNDER WATER

“That’s what it is, Jack,” said Dick, after the first sensation of astonishment had passed.  “It is more in the bow than on the side, however.  You can see how she narrows a little farther on.  This hole is pretty well forward.  I tell you what!  This is the vessel we saw under water, or the one that stump of a mast belongs to, at any rate.”

“I believe it is, Dick.  Probably she drove in here, had a hole smashed in her bow, and then sank.  The earth has settled in between the masses of rock above and around her, and hidden her, but there is still the fissure down which we have just come.”

“This is as good as finding Captain Kidd’s treasure, isn’t it?” exclaimed young Smith.  “We never expected to find anything.  Shall we go in and see what more there is, Jack?”