Out came the moon again, sailing into a clear field.

But Jack no longer stood there on the little beach. He had taken time by the forelock, and slipped among the rank growth; so that although Josh strained his eyes to the utmost, not the faintest sign of his comrade did he discover.

Jack’s idea, of course, was to reach the vicinity of that tumbledown shack. In his mind, that must be the central point of interest in the game. He fully believed, though he had not mentioned the fact to the rest, that the attempt to frighten the boys off with such a ridiculous show of a pretended spirit waving them away, was meant to cover this cabin.

What did it all mean? Why should any man, or set of men, wish to keep others from prowling around that rickety building? Surely, any one with common sense would hardly think to occupy it for a night’s refuge. The open air would be far more preferable in every way.

Still, Jack was positive that there was something in connection with this same cabin that moved the unknown parties to endeavor to influence an early departure on the part of the motor boys.

And he wanted to know what that mystery might be.

That was why he had come ashore so silently. It also accounted for his creeping along through the bushes as carefully as he knew how, avoiding the trail which he and Josh had followed on that other occasion.

It took him considerable time to draw near the vicinity of the cabin, because he wanted to go without making any noise; and he was not positive but that hostile eyes and ears might not be on the alert.

Twice some sudden little sound close by had sent a thrill of alarm through his heart. But nothing followed, and he realized that these noises must have been made by some little animal, disturbed in his retreat by the creeping past of the intruder.

Jack had made a discovery before he was more than half way between the beach of the cove and the cabin. There was a light inside the old building! He could see little glimpses of it through what must be holes in the walls, where the chinks between the logs were open, the mud having fallen away in the process of decay.

And as Jack said to himself with a chuckle, ghosts did not, as far as he knew, need lanterns in their business.

Finally the boy found himself close to the side of the cabin. With his heart beating like a trip-hammer, he crept to the first little gap in the wall, and glued his eyes to the aperture.

What he saw was nothing so very astonishing. A man stood inside the cabin, holding a lantern. He was not doing anything, and seemed to be waiting for some other person.

“One of the fellows in that boat today,” was what Jack immediately said to himself, as he fastened his eyes on the bearded face.

Even inexperienced as he was, Jack fancied that there was something of a desperate type about the man’s countenance. He did not seem to be such a man as one was apt to trust on sight—like that jolly professor from Ann Arbor, for instance.

But what on earth could the man be doing here? He did not seem to have any sort of bundles with him, as might have been expected. Once Jack was made to shiver just a trifle, when he saw the fellow take out a pistol, and handle it with a grin of pleasure on his face.

Jack was beginning to see light. This could not be simply the ordinary desire of some fishermen who disliked seeing strangers occupying a cove they had come to look upon as theirs by right of previous use.

And this man he now saw had none of the characteristics of a rough fisherman. He was rather nattily dressed, and would pass for a gentleman in a crowd. The mystery seemed to grow more dense; but as it is always darkest just before dawn, so Jack believed that he must be on the point of seeing daylight appear in this matter.

By chance he raised his eyes a trifle. Perhaps some little movement may have attracted him—he never knew. But again he was thrilled to discover a face pressed against the broken pane of glass forming the sole window on the opposite wall.

It was the strange gentleman who had claimed to be a college professor. He did not wear his nose glasses now, and doubtless the look of culture had given way to one of an entirely different nature; but Jack knew he could not be mistaken.

Nor was he so very much surprised, come to think of it. He had half anticipated something of this sort, at the time he heard what seemed to be the peculiar chug! chug! of the noisy motor belonging to that snub-nosed boat. The professor had indeed come back to the haunted island; nor had he thought it advisable to inform his new boy friends of his return.

Had Josh been there to see, he must have surely jumped to the conclusion that it was his wild desire to set eyes on a ghost that had lured the professor back.

Jack looked at the matter from an entirely different standpoint. He, for instance, did not believe that the gentleman was one-half so much interested in mysterious visitations from departed spirits as he was in the movements of certain persons who might be engaged in a trade that shunned the light of day, because it was by nature evil, and in defiance to the laws.

And this party who stood there, holding that lantern and waiting, was evidently something in the line of a leader.

Only for a brief space of time did the so-called professor remain at that broken window; then he vanished from the view of the watching boy. But it gave Jack considerable satisfaction and confidence just to know that Herman Marshland was near by.

Already he had his hand upon the solution of the whole puzzle that had been eluding his best efforts up to now. And just like Columbus discovering America, it was so exceedingly simple, once you knew how, that Jack silently laughed at himself for not having grasped the prize answer before now.

Smugglers, that was what the rough-looking men in the boats were! This must be a central point with them, where for some time they had secretly landed the goods ferried over from the nearby Canadian shore. Here on American territory they were perhaps secreted until such favorable opportunity arrived to send them further afield into the sovereign State of New York, when all trace of them would be lost to any government agents who might be prowling around on the lookout for such law-breakers.

Since coming to the St. Lawrence the boys had heard more or less about such a class of persons, who made it their business to try and evade the revenue men. In some cases it was Chinamen they shipped across the border, receiving so much per head to get them into the protected country. Then again it meant laces, diamonds, silks, anything that was small in dimensions, but upon which the government at Washington levied a heavy toll.

Pleased with having guessed the secret, Jack could not think of slipping away. It might be none of his business what these bold and bad men were doing; but somehow he could not help feeling a deep interest in the movements of the man who had visited them that very afternoon, and made such a hit with the boys.

Of course the pretended college professor must really be one of those sagacious revenue men, engaged in running these rascals to earth.

Besides, the “professor” might need help, and Jack was of a mind to render such a service if the chance came. A strange freak of fortune seem to have thrown them in contact with these warring factions; and while some timid people might consider it the height of folly for any one of the boys to take sides, Jack’s bold spirit would never allow of his standing there and seeing the man who represented law and order outclassed.

He half expected to see the “professor” step into the cabin through the doorway, and call upon the unknown man to surrender. But then, as there was as yet no evidence of crime, possibly a cautious revenue agent would be apt to hold his horses and await further developments.

A sound came faintly to the ears of the crouching lad—voices of several persons, and approaching the cabin at that.

Jack dared not keep his position, with his eye glued to the crack; there was a chance that he might be discovered; and so, although he wanted to look more than ever, he dropped flat upon the earth and waited.

At any rate, he had made no mistake about others approaching, for presently he knew they had entered the cabin. After that he ventured to look again. Yes, two rough-looking fellows had entered, and were already conversing in low but eager tones with the one who had waited for their coming.

Seeing was all very well, but just then Jack thought that if he could only hear what was passing between these fellows he would have the last bit of fog cleared away. To this end he clapped his ear against the side of the cabin at the very point where the mud had fallen, leaving a hole in the chinks between the logs.

Nor was he mistaken when he believed he might pick up some of the words passing between the men. The two newcomers seemed more or less worried about something, and kept urging delay; but the leader would have none of it, apparently.

“Antoine,” he said, gruffly, “you go and watch the three boats lying in the cove. If there’s any sign of life about them, come back and warn us. We must get those goods ashore tonight. It’s too risky holding them any longer. And one of the cubs might break away, to inform on us. That would ruin all. Bart, you be off and start things moving this way. I know the new trail is rough and long, but it can’t be helped. Next time we’ll have things back the old way again. These kids ain’t going to hold on much longer. Now, both of you be off!”