"What's a cap?" Tom eagerly asked. "I don't know about this."

"I couldn't help but notice it," Jack scorned. "Well, it's just this way--You see, dynamite will burn without exploding. A very little jar, however, sometimes is sufficient to set it going and explode it. When setting off a charge, a cap containing some fulminate of mercury is put over the end of the fuse. That stuff will explode from fire. When the fuse burns down to the cap, the cap explodes and the jar of its explosion sets off the dynamite. See?"

"Thanks," gratefully replied Tom. "Now I'm enlightened. Then the reason the Fortuna is still here is because the guy forgot to put his cap on his fuse? Am I now correct?"

"Right you are, Tom," answered Jack. "Are there any further questions?

If not, the cla.s.s in explosives is dismissed."

"One more, Professor, if you please." Frank had the floor. "What shall we do with the stuff? We don't want to keep it aboard."

"That's a problem," Jack announced. "We can't merely throw it overboard; nor we can't leave it in a fence corner. I'll confess I'm puzzled to know how we shall get rid of it."

"Let's leave it until morning," Tom suggested. "Just now I'm so worn out I can't think. I wish we had Wyckoff here, I'd put it in his pockets and then climb a telegraph pole with him and throw him down good and hard.

When he landed it would explode and he'd get his."

"Sure," laughed Frank. "Listen to the bloodthirsty Thomas. What do you suppose would be going on up the pole all that time?"

"Well, I'd be there watching for Wyckoff and when the explosion blew him up, I'd reach out and slap his wrist as he went sailing by."

"Well, he isn't here and probably won't be here for some time, either.

We'd better get to sleep," Jack stated. "Tomorrow bright and early we'll get those carpenters at work. One plank is a short job and then it'll only be a few minutes work for all hands to slap on the copper paint and into the water she goes. We should have the Fortuna afloat before noon if everything goes well."

"Hurray!" cried Tom. "Then we'll go up to the cabin--"

His voice lost its ringing, cheery tone as he thought of what they might find at the cabin. No one could speak for a few minutes.

At last they composed themselves for slumber in the after cabin that the boys liked so well. It was fitted up with souvenirs of their various trips. Here a pair of wings from a great snowy owl that Tom had shot.

There a stuffed porcupine that caused such a commotion in their camp in the Canadian wilds of Georgian Bay. Here were the jaw bones of a giant muscalonge that had taken the bait at sunrise one morning as Harry was trolling from a skiff in northern Michigan. So on it went with various trophies of the hunt and chase. The room was their parlor, where they gathered for a pleasant evening and where they preferred to spend the night.

Rowdy curled on a rug in the middle of the floor. One eye was open. Ever as he slept or dozed his limbs twitched convulsively and he moaned and muttered in his fitful unconsciousness.

No disturbance wakened the boys that night. They slept soundly as only healthy, hearty boys can sleep when their minds are filled with pure thoughts of sport and active out-of-doors life. As yet they had not been tainted with the many things that go to disturb rest. Their everyday training at the Beaver Patrol club rooms had been along right lines.

Their Scout Masters were all young men of high ambition whose purpose was to teach their younger scouts that highest, n.o.blest lesson--that man is here for a purpose and that purpose is not a selfish one. Thus far their teaching had not been in vain.

With the early beams of the morning sun Jack was awake.

"Come on, boys," he cried. "We'll have to bathe in a pint bowl this morning. No hose for us today."

"Well, if we can't have a shower bath, let's take a quick cold sponge and then have a little setting up exercise," suggested Tom.

Their actions were a revelation to the watchman who was now just recovering from his stupor of the night before. His brain was still so befuddled by the liquor that he could not at once understand what was going on about him. His surprise pleased the boys.

"What'll we have for breakfast?" asked Tom, and then added, "Suggest something easy, for I'm cook, you know."

"Pancakes," cried Frank. "Those you made when we were leaving Pet.i.t Bois were just about the best I ever ate."

"Pancakes it is, then," agreed Tom dashing to the kitchenette, where he proceeded to prepare a breakfast of delicious pancakes and coffee. A few freshly boiled shrimp added to the feast were welcomed by the boys. A pa.s.sing fisherman had offered them to Jack at just the right moment. The boys did ample justice to the feast.

Leaving the foreman to superintend the matter of replacing the plank where Wyckoff had bored the hole in his dastardly effort to sink the Fortuna and her crew, the boys took a boat from the Fortuna and rowed up to the leaning oak. From thence it was easy enough with Rowdy's aid to trail the route to the site of the cabin in the clearing.

The embers had now cooled sufficiently so that the boys could search in the ruins. For a moment they hesitated to explore the ashes, fearing what they might find. A last they plucked up their courage and began a thorough search. The task was not a pleasant one.

"What's this?" cried Tom. "Boys, I declare I smell burned flesh. That odor hangs around here something fierce."

"Well if that big Doright was telling the truth," Frank argued, "the boys got out of the cabin and were safe last night. How about it?"

"You can't tell anything by what that fellow said," Tom replied. "He just saw that we were worried about the boys and wanted them to be safe, so he said they were safe. That's all there is to that."

"He's considerable of a child," Jack announced. "They all are."

During this time Rowdy had been circling the spot where the cabin had stood, occasionally sending up a doleful howl.

"Watch Rowdy," Tom declared. "If he isn't an indication that something happened here last night, I'll miss my guess."

"Well, I don't believe that what you mean did happen," Jack contended.

"If it was so, Doright would have acted differently. He was very composed when we saw him and that bluff he put up about this being his farm showed that he knew where the boys were all the time."

"Then what do you suppose happened to them?" Tom's voice broke.

"I don't know. They're around here somewhere. Of that I'm sure. They are not far away," Jack stoutly contended.

"What do you think Frank?" was Tom's almost tearful query.

"I think we'd better not make up our minds until we get some better evidence than a smell or a negro's word. Let's keep digging."

Accordingly the boys vigorously attacked the plan they had in mind of stirring about through all the ashes in search of a clue to the whereabouts of their chums. At last a shout from Tom proclaimed a discovery. His friends rushed to his side.

"Right here by the chimney." Tom broke down. "There it is."

"Now, Tom," half scolded Jack. "Brace up, boy! Suppose it were reversed.

Would you want them to squall over you?"

"I can't help it," the boy answered. "I am not squalling, but I feel badly to lose a chum like those boys were. So do you, too."

"I sure do," answered Jack poking about Tom's discovery. "I'd feel awful to lose a good friend even if he was a black sheep."

As Jack spoke he held up on the end of a stick a small tuft of wool which had adhered to the end of his staff. With it came the odor of burned flesh again. Jack smilingly pulled Tom's sleeve.

"The boys are safe," he said, exhibiting the wool. "It was a black sheep that burned. Arnold and Harry are not black sheep."

"Good, oh, goody," cried Tom, capering about. "That's just fine."

In a short time the boys finished their search now fully convinced that whatever might have happened to Harry and Arnold they were not now in the ruins of the burned cabin.

"Now let's get Rowdy to help us track the boys to wherever they went,"

suggested Tom. "I'd like to find 'em."

"Good idea," responded Frank. "Let's do that. Here, Rowdy."