“Then there is not much use in our going any farther, Jack?”

“No, not if we want to find Rollins and the rest.”

“Suppose we take the widest passage, Jack!”

“Very well.  Come ahead.”

They went on for twenty feet, when the floor of the passage began to take a sudden decline which increased at every step.

“Hold on, Dick,” said Jack, holding his light low and flashing it along the rough floor.  “This thing may take a sudden drop and——­”

“So it does!” gasped Percival, lying at full length on the floor and crawling carefully forward a pace or two.  “It takes a drop for fair.  It is a lucky thing you noticed it.”

“Then we may as well go back, for I don’t care to take a drop I don’t know how deep.”

“I’ll see,” muttered Percival, picking up a loose stone as big as his fist and tossing it ahead of him.

Not until several seconds had passed did the boys hear the sound of the stone falling into water, and Percival said with a sigh of relief: 

“Well, we didn’t go that way, at any rate.  Come on, Jack, there is nothing to be seen in that direction.”

The boys returned to the place where the passages diverged, and Percival suggested that they take one of the narrower paths and follow it for a time.

“All right,” laughed Jack, “but I don’t believe we shall find any more than we have already found.  In fact, I don’t believe the smugglers know of this place at all and we won’t find out anything.”

However, they proceeded down the narrow path till they suddenly found themselves at the end, where the place widened into a chamber about ten feet square, and here they saw a sight which made Percival tremble.

It was a pile of human skeletons reaching nearly to the roof of the vault and thrown promiscuously about like so much rubbish.

“I say, I’ve got enough of this!” gasped the young fellow.  “Let’s get out of this, Jack, before we find anything worse.  First the bottomless pit and then a charnel house.  I am satisfied!”

“It is not a very pleasant sight,” said Jack musingly, “but they cannot do us any harm.  They have probably been here for years.”

The boys returned to the chamber they had left and then went back along the way they had come without seeking to explore any other passages.

Getting out into the light at last, they proceeded with their search for the smugglers, resolving not to enter any more mysterious caves, but to look for places where a vessel might be able to hide.

“There must be a lot of coves along here,” said Jack, “that we have not been able to find on account of the difficulty of making one’s way along the rocks, but now we are looking for them we don’t mind doing a lot of scrambling.”

“No, we are used to that, and, besides, we are alone, and haven’t young Smith with us.  I suppose he would have been delighted to come, for he likes being with us, but it would have been too much of a task for him.”