asked the professor, in evident alarm.

"I don't think there is much choice in the matter," confessed the captain. "We may go to pieces if we try it, and we are pretty certain to go to pieces if we don't."

The yacht was now rolling and pitching on the heavy seas, and the blasts of wind were becoming stronger and more angry, whistling through the rigging with the shrill sound of a gigantic fife.

"Shall we take in another reef?" shouted the mate.

"No. Put two men at the wheel and tell them to work lively! Jim, a few words with you."

A brief conference followed, then taking his station amidship, with Jim well forward, the captain shouted his orders to the sailors and helmsmen. Jim signaled by means of a pocket handkerchief in his hand, facing first the course of the channel, and at intervals looking toward the captain. Every motion was correctly interpreted by the commander.

"The helm to the port side! Port your helm! Jam it down hard! Haul in the main sheet; haul close! Quick now! In with the lugger and jib!" The captain was hurling his orders so quickly that his words tripped over one another.

The men sprang to obey the commands. The yacht meanwhile entered the channel between the cliffs and was driving headlong for the rocks ahead which presaged a certain end to its career. But just as the fatal crash seemed imminent and unavoidable, the bow swung around, and with the end of the boom buried in the foam of the breaking waves the Storm King glided into the deeper waters that opened to the right.

"My goodness!" cried Tom, drawing a long breath, "but that was a close shave. I thought we were gone for sure. I don't mind things that happen on land, but that's the worst experience I've been through yet."

"Oh, cheer up," cried Jo. "There is plenty more to come."

"It's a good thing we had a good captain," said Jim. "That was a nice bit of work."

"Worthy of one of the oldtime pirates," added the rea.s.sured professor.

"I'll have to bring that in."

The captain awarded full credit to Jim's skill as a pilot. It was another instance where close observation had brought worth while results.

While they were talking, the yacht had run into the inner harbor, and here even with the fierce wind playing havoc in the tree tops and out at sea, the high hills afforded good and safe shelter.

CHAPTER XVIII.

A MYSTERIOUS HAPPENING.

The barometer rose shortly and climbed up as rapidly as it had earlier fallen. In a brief time the skies had cleared and the wind settled to a steady breeze.

"It seems to me," said the professor, looking about him, "that it was a difficult thing to get in here, but to get out is going to be a more difficult one."

"It will be all right," replied the captain, "if Berwick will fix up that old tea kettle of his and give us some steam." Then addressing the engineer, "Can't you do this while we are in here?"

"Maybe I can," replied the engineer, "if there is no more of the devil's handiwork. There would not be much the matter with the machinery, if there was not somebody undoing things."

"The sailors will have few duties, now, and we will have a double watch set over the engine room," said the captain.

The distance to sh.o.r.e was now so short that getting back and forth was a simple task, and as security was so seemingly a.s.sured, permission was given for any outside of those on duty, to land and rove about at will.

"As we have found the island, let's find the cave," suggested Jo, as they were preparing for a trip ash.o.r.e.

"Then we can go home," added Tom, who, however ready to venture forth, was even more disposed toward the home journey. Whatever desire he may have had toward early home going in this instance was destined by events he could not forecast, to be blotted out.

"There is that column of smoke again," announced Jo, as he grasped the oars. His brothers and Juarez were with him in the boat.

The others once more observed the curious signal, if such it were, but gave no special heed other than to note its distance. On land, however, they bent their footsteps in the direction of the phenomenon although they could no longer see it for a guide.

They found themselves trailing off on a route they had not before taken, and had gone perhaps half the distance which they had estimated as required, when they came upon a curious clearing in the woods. It was about forty yards in diameter, and surrounded by a complete circle of trees, their boughs interlacing about seventy feet above to form a lovely green canopy. So regular were the trees that it seemed as if they had been planted by human hands hundreds of years before.

At first they did not notice, because of the somewhat dim light, that on the far side of the amphitheatre there rose sheer a wall of rock well covered with vines, and then all of one accord and simultaneously exclaimed.

"There's a cave!"

"Hurrah, we've found it," added Tom.

"Don't go so fast," admonished Jim. "There may be more than one cave on the island."

"But the opening is high up," demurred Tom, "and it looks as if it might be hard to get into. How shall we do it?"

All thought of the column of smoke was blotted from their minds as they surveyed the task before them, so suggestive of sought-for achievement.

The opening to the cave was fully forty feet above the level on which they stood. No safe foothold could be discovered on close examination of the face of the rock which rose sheer to the top, perhaps a hundred feet.

"I'll warrant there is some other entrance," suggested Jim. "Seems to me this place we are in was one time a sort of temple or auditorium, and that opening up there in the rock may have been the pulpit."

"It's sure no easy job to get up there from this level," admitted Jo.

"Suppose we deploy around and hunt for the side door."

This they did, that is, Jim went one way, while Jo and Tom sought for an opening in the opposite direction, but without success.

Juarez had meantime studied the face of the vine clad rock below the mouth of the cave, and when his companions returned he undertook the ascent or climb. Mounting first on Jim's stalwart shoulders he found creva.s.ses into which he dug his toes, and with his great knife scooped out fragments at irregular distances, thus by degrees mounting to the cave's mouth.

Once a secure footing gained, he let down his lariat, and one after the other, the boys climbed up, and all stood looking out upon the auditorium below. Surely a more beautiful green bower of exaggerated proportions could not be imagined.

But it was not scenery that had induced them to seek the cave, and at once their thoughts turned to the business at hand.

The floor of the cave was dry, and the place showed no signs of recent occupancy. It extended into the rock beyond the limit of vision.

Jim had thoughtfully gathered and sent up a bundle of f.a.gots, some dry slow burning sticks, one of which was now lighted. The blaze cast a fitful glare upon walls that shown in places with metallic gleams.

While Jim and Juarez busied themselves near the entrance with the digging into and examination of some mounds of earth which excited their curiosity, Jo and Tom with the burning f.a.got penetrated deeper into the tunnel, for such it seemed to be. It presented at the start nothing out of the ordinary. It was simply as Jo put it, an enlarged burrow of irregular width and height, varying in width from six to eight feet and in height the same. The sides were of earth with here and there a stone.

Whether of natural formation or an artificial construction the boys could not determine.

"Doesn't seem to be anything worth seeing in here," said Tom, who was in the lead and carrying the torch. "We might as well go back."

"Oh, go on a little further," urged Jo. "Perhaps we shall find something."

"I'll bet, if we do, it's something we don't want," objected Tom.

"Well, we needn't take it if we don't want it," retorted Jo. "Let me go ahead."