Both boys read the "mysterious guy's" first send with eager impatience.

It was as follows:

"He's making sport of you. Mark my word, when you reach the island, he'll be gone."

"Keep out, you pirate," ordered Hal.

"All right, but you'll call yourselves a bunch of fools."

The next instant the "island prisoner" broke in thus:

"Hurry; they are after me. I think they are the ones who marooned me here. Their boat looks like yours, I guess."

"See!" exclaimed Bud. "This makes things look bad. If those fellows are robbers they're armed. We haven't a gun on board, and if we had we wouldn't want to get in a fight over an affair that looks more like a joke than a tragedy."

"And yet it may be a tragedy," said Hal.

At this moment Cub reappeared in the cabin and the situation was explained to him.

"It begins to look like a tragedy," he admitted; "and yet if we treat it as a tragedy and it proves to be a joke, we'll feel like a comedy of errors."

"Now, you're getting highbrow, Cub," was Hal's mock objection.

"It's common sense, isn't it?" the youthful philosopher reasoned.

"Yes, but you forget one thing," the sly-eyed Hal rejoined: "With so much Q R M, it's very hard to pick out common sense in an affair like this."

"That's true," replied the other. "We've had more interference in this trip thus far than anything else."

"And the big question now is, how're we goin' to tune it out?"

"I confess, I'm stumped," said Cub. "Guess we'll have to refer the whole matter to father, but I bet he'll be up against it just as much as we are."

Cub turned toward the companionway with the intention of seeking an interview with Mr. Perry in the wheel house, but Hal delayed him again.

"Wait a minute," said the operator. "Here's our island friend again."

Cub and Bud donned their phones once more. The message received was more startling than any preceding.

"They are coming ash.o.r.e," was dot-and-dashed into the three boys' ears.

"I see four bad-looking men. I am going to run before they see me and--maybe--swim. Good-bye."

"What in the world shall we do?" exclaimed Bud.

"I'm going to find out," declared Cub, as he dashed out of the cabin.

Hal, meanwhile, was busy again. The mysterious amateur who had persistently attempted to turn the supposed near-tragedy into a joke was spitting the Catwhisker's call again.

"Fools!" he flashed spitefully. "Goodnight."

CHAPTER VI

A Mystery and Cub's "Goat"

Cub hastened to his father and gave him a rapid narrative of events as they had been received by wireless.

"Well, that's interesting, to say the least," observed Mr. Perry with a look of curious amus.e.m.e.nt.

Cub waited a few moments for further comment, but as it was slow coming, he asked impulsively:

"What are we going to do?"

"What do you think we ought to do?" inquired the man at the wheel, looking sharply at his son.

"I don't know; I'm stumped," was the boy's reply.

"That's a frank admission. First time I've known you to admit such absolute defeat. Do you think we'd better turn about and go back home?"

"No," Cub replied with a revival of decision in his tone of voice.

"Well, shall we stop, turn to the right or left, or go ahead?"

There was a slump to indecision again. Cub looked foolish. His father was making sport of him and he did not know how to answer intelligently. In desperation, however, he replied:

"Go ahead."

"What for?" asked Mr. Perry. "Shall we dash to the rescue and face those four men, who probably are armed with pistols?"

"No, of course not. Anyway, we don't know where they are. They may be twenty-five miles from here, for all we know."

"Then we'll have to give up the search if you don't get any more messages from him," declared the boy's father.

"That's so," Cub admitted. "And if those men captured him and took him away in their boat, this affair will have to remain a mystery in our lives forever afterward."

"You'd better go back to the cabin and see if Bud and Hal got any more messages from him," suggested Mr. Perry.

"That's the only hope left," said Cub as he turned to go.

But this "last hope" proved to be vain. Bud and Hal were both still listening-in, but with little suggestion of expectancy on their countenances.

"Anything more?" inquired the tall youth, unwilling to put his question in negative form, in spite of the fact that his better judgment would have dictated it thus.

Both listeners shook their heads.

"Then that's the end of our search," Cub declared with a crestfallen and disgusted look.