"Not likely, Sam. I don't believe it has ever been used. But if it was of good size it might prove handy for us at some time or another." They looked around, and finding some dry brushwood made two rude torches. With these flaring brightly they entered the opening, the flooring of which was of rock and tolerably smooth. "We could live in this cave, if it wasn't that the opening to it is in the gully," said Sam as they advanced. "There may be another opening at the other end," said Tom. "It is certainly quite long." They had advanced fully a hundred feet, and now found themselves in a chamber forty or fifty feet square. The ceiling was arched and so high that they could not touch it without jumping up. "This is as good as a house," said Tom. "See how dry the flooring is. That proves that it is waterproof." From the large chamber there were several passageways, all leading toward the bay. "Which shall we investigate first?" asked Sam. "Let us start at the right." "All right, Tom; the right ought to be right," answered Sam lightly. On they went once more, the flooring now sloping before them. Here there was considerable moisture, and they had to walk with care for fear of slipping down. Suddenly a number of bats flew out of a hole nearby, dashing against the torches and against the boys themselves. The rush was so unexpected that each youth dropped his light and put up his hands to protect himself. "Get out! Let me alone!" spluttered Sam. "Whoop!" roared Tom. "Confound the bats anyway! Get along and let us alone!" Lying on the flooring the torches soon went out, and in their efforts to protect themselves from the bats the boys rushed blindly down the passageway. Then of a sudden both slipped on the wet rocks, slid a distance of several yards, and went down and down, landing into a well-like opening with a loud splash! CHAPTER XXVI THE CAVE ON THE ISLAND "Tom!" "Sam!" "Are you safe?" "Yes, but I wasn't looking for such a cold bath as this." "I guess we must have fallen into a regular well of spring water." "Never mind what we are in. The question is, how are we to get out?" "Can you touch the top of the opening?" "No." "Neither can I." Luckily the two boys could touch the bottom of the hole, so they were in no danger of drowning. They were in water up to their waists and calculated they had dropped a distance of two or three yards. All was pitch dark around them and as silent as a tomb, save for some water which trickled close at hand. The bats had departed, leaving them to their fate. "This is cave-investigating with a vengeance," said Tom, with something like a shiver. "Never mind, Tom, we won't die of thirst anyway." "Do you think this is a laughing matter, Sam?" "No, I don't. I'd give a good deal to be out of this hole and out of the cave also." "I've got an idea. Let me climb on your shoulders and see if I can reach the top that way."