"It does not seem likely, Dick," said Jack in a doubting tone. "There was no one about, and we are the only ones who know the place. We said nothing about it, and young Smith will keep quiet. Come, that is hardly worth thinking of. Let us see how we can get out. There must be some way."
Dick turned his light this way and that, and Jack lighted a match, saying with a significant chuckle:
"That is all very well, but this is better for our purpose. Watch!"
The flame presently began to flicker, and indicated the presence of a draught of air, Jack noticing the direction whence it came, said:
"Try this way, Dick. There is a draught which makes the flame flicker. Try the axe on the rocks and see if you can loosen them, or, better yet, see if there isn't a fissure somewhere."
"Yes, there is," said Percival, climbing a mass of rock somewhat to one side of where the others had fallen. "Yes, I see it, Jack."
Between them, working with the axe and their hands, the boys opened up a passage between the rocks wide enough for them to crawl through, and in a few minutes were on the top of the wooded point only a few yards from where they had entered the strange place.
"The boat's gone, Jack!" exclaimed Percival.