"What do you make of it, Elmer; is it a sure enough bomb?" demanded Lil Artha, whose face was working strangely under the violence of his emotions.

"Looks like it was that, and nothing else," admitted the scout master, slowly, with a wrinkle across his forehead, as though he might be considering weighty matters, as indeed he was just then, for one so young.

"And there can't be any doubt but what he meant to blow up the cabin of the man he forced himself to believe was his enemy, the kindest-hearted gentleman you and the rest of us ever met up with—tell me that, Elmer, didn't he?"

"Hold on, Lil Artha, don't explode!" cautioned Elmer, soothingly. "I understand how you feel about this ugly business. Yes, that must have been the scheme that brought Zack away up here in the dead of winter. Whether he meant to do Uncle Caleb bodily injury or not we've no means of knowing. Let's hope that the limit of his revenge was confined to the destruction of the cabin, and all the valued treasures it held."

"Well, that would be arson, and the law sits down mighty hard on anybody who deliberately, and 'with malice aforethought,' as I've heard my dad say, sets fire to the property of another. He deserves being kicked out, and we'll have to attend to his case, the whole bunch of us."

The excited scout made a quick movement, as though about to rush into the cabin, waving the piece of gas-pipe which had been fashioned into a rude but deadly bomb with a fuse to it; Elmer, however, tightened his grip on his chum's sleeve.

"Wait! Don't be in such a hurry, old fellow. Let's reason this thing out a little before you spill the fat in the fire!" he told Lil Artha, in that quieting voice of his that carried such weight with the other scouts.

"But, Elmer, don't you see he's a regular firebrand!" urged the tall boy, twisting a little, as though struggling to get loose from the detaining hand; but only in a faint-hearted fashion, because as always the influence of the scout master predominated. "How do we know but what right now he's figuring on doing us all some mean trick? We're friends of Uncle Caleb, and he must look on us as his enemies."

"You forget something, Lil Artha," urged Elmer.

"Oh! yes, in my hurry I'm always forgetting things; but tell me what I've let slip now, Elmer."

"It was yesterday that Zack was heading toward this cabin, breathing all sorts of ugly threats against Uncle Caleb, wasn't it?" Elmer continued, in that smooth argumentative tone he knew how to use so well, and which as a rule was so wonderfully convincing.

"Why, of course it was, Elmer," admitted the other, weakly, yet curiously.

"And something has happened since then, you know, Lil Artha?"

"Oh! sure, several things," replied the tall scout.

"Zack Arnold had an accident, and found himself facing what might be the end of his evil career," continued Elmer. "Now, life is sweet even to such a man; and he couldn't but feel alarmed at the idea of being frozen in the snow forest, because of his broken arm, and having no way to supply himself with food or fire. Then in his desperation he forgot everything else, and came to the cabin of the man he had been calling his enemy. You know what sort of a reception he got, Lil Artha?"

"You bet I do, Elmer; it couldn't have been warmer if he'd been a life-long comrade of Uncle Caleb!"

"All right, then," the scout master told him, emphatically; "and you can depend on it Zack has had an experience unlike anything he ever ran up against before. I've been watching him, and trying to figure out what might be passing through his brain; and the fact of his throwing this bomb as far away as he could shows that he's heartily ashamed of ever entertaining the notion that Uncle Caleb was an enemy of his."

"Do you really think so, Elmer? And could such a scoundrel ever reform?" asked Lil Artha, half skeptically, just as though he were Doubting George.

"Of course I wouldn't like to stake my reputation on it," Elmer continued; "but all the signs point that way. The man is just now in a daze. He never met with anything like this before, and hardly knows what to make of it. In other words, Lil Artha, he has arrived at the cross-roads, and the next few days will either see him turning over a new leaf, or going back to his old ways again. It must depend pretty much on Uncle Caleb."

"I reckon it will, Elmer!" muttered the tall scout, beginning to drift across the line, and agree with what the other advanced. "And don't you think we ought to let Uncle Caleb know about this gas-pipe thing?"

"Yes, but I don't think it'll make any difference with his way of treating the man. Uncle Caleb has sized Zack up to a dot, and he's trying to get the whip-hand over him by sheer kindness. And I think he will, sooner or later. It wouldn't surprise me if it all ended in Zack turning right-about face, and caring for Uncle Caleb just as much as he thought he hated him. Such men when they do change never make a half-way job of it; they go the whole thing."

"Shall I call Uncle Caleb out here now while we're at it, Elmer?"

"I'll do it, and you wait here," the scout master told him.

"All right, then; you know how to go about it better than I do. I'll be ready to spring my little surprise on our host," said Lil Artha.

So Elmer stepped over, and opening the door quietly, caught the eye of Uncle Caleb, when he crooked his finger. The meaning of this gesture could not well be mistaken, and presently the old scientist joined them outside the cabin, making some excuse as he passed out.

When Lil Artha showed him the queer piece of gas-pipe that had been charged with some high explosive apt to carry great destruction with it when discharged, Uncle Caleb did not appear to be greatly astonished.

"I imagined it might turn out to be something of the sort, boys," he informed the scouts; "and it was my full intention to look around later on, so as to discover what it was Zack threw away last night; for I saw him standing there in the doorway just as both of you seem to have done. You've saved me the trouble of making the search, Lil Artha. But let me hide this ugly thing. I wouldn't like Zack to know it had been found so soon."

"Then you won't turn him out for coming up here on such a terrible errand?" asked Lil Artha, weakly.

Uncle Caleb looked at him, and smiled. Lil Artha understood then what was in the mind of the kindly scientist, who loved his fellow men so well that he could even believe the worst of them must have some good in him, however small, if only one could discover its location, and coax the wavering spark to glow into a steady flame.

"I don't believe Zack ever had a chance," he told them, seriously, "and I'm going to give him one right now, if it's in my power. As scouts, neither of you would surely deny it to him, I'm certain. Besides, it's going to give me considerable pleasure in studying the working of the germ that has been planted in his heart by this piece of good luck. Perhaps that broken arm may mean everything to Zack Arnold. A year from now we'll take stock, and see how things come out. In the meantime say nothing, and leave it all to your Uncle Caleb."

Willingly both boys declared that they were only too glad to do so. They asked, and readily received permission, to tell George and Toby, when a chance came. And as they entered the cabin later on, to see Zack still following Uncle Caleb with his wondering, yes, even admiring glance, it struck the scouts that perhaps the sensible old scientist had made a study of human nature as he had the habits of wild animals, and knew full well what he was doing.

During the balance of that day he treated the wounded man just as though the intruder might be one of the family. Uncle Caleb was too wise to gush over the injured guide; he simply showed Zack that he had a deep interest in his welfare, and meant that he should have every care while unable to look out for himself that could be expended on him.

Elmer, who was observing these things closely, without betraying the fact that he had more than a passing interest in them, told himself that it would not be surprising if when they came to leave the cabin in the forest a pact had been arranged between Uncle Caleb and Zack Arnold, by means of which the big guide was to stay up there the balance of the winter, and act as a side partner to the man he had once been so foolish as to consider his enemy.

"There'll be no chance for him to hobnob with his real enemy, which you can take it from me is strong drink," the scout master told the other boys when they talked matters over, away from the cabin that afternoon; "and before spring comes, I wouldn't be surprised if Uncle Caleb has weaned him from his old habits, so that nothing can ever tempt him to go back to them again."

"I hope you're right, Elmer," ventured George; "I don't feel quite as strong as you do about it, because I just can't, that's what; but it'd be splendid if Uncle Caleb did reform that beast."

"And I think it's just wonderful," Toby admitted, having heard the whole story with great eagerness and interest; "I never knew Uncle Caleb was such a splendid sort of a man. And honest now, I don't see how any fellow could hold out against his winning ways. No wonder Zack keeps watching him all the time; I tell you he's as near hypnotized as anybody could be."

And so they concluded to let the matter rest, confident that the good man of the lonely cabin in the snow forest knew what he was doing, and that the chances were he was not making any mistake.

The boys now proceeded to enjoy themselves to the best of their ability, each according to his bent. Of course all of them were keenly interested in the remarkable success with which the scientist was meeting in his effort to secure amusing and instructive flashlight pictures of the woods animals at night. He showed them how he set his snares, so cleverly arranged that when the fox or the mink came to take the tempting bait that had been cunningly placed, he was compelled to pull a cord that released the hammer by which the fulminating cap was detonated, and the flashlight cartridge set going, thus causing the little animal to take his own picture.

That very night every one of the four scouts accompanied Uncle Caleb to set several of these ingenious traps. The novel experience appealed to all of them; and even Lil Artha, usually an ardent hunter, was heard to admit that it afforded all the excitement necessary for enjoyment, anticipation and realization combined, without having to destroy the life of the cunning little creatures that, in roaming the woods, and seeking their natural food supplies, were only working out their individual destinies.

"Anyhow," Lil Artha confided to Elmer, later on, when they were returning to the warm cabin where Zack had been left in full charge, "I don't believe I'd like to become a regular fur trapper, though once on a time I did seem to hanker after such a life. It's all well enough to shoot game when you're hungry, just like you'd knock over a chicken when the dominie is coming to dinner; but this thing of trapping little things like mink and muskrats just for the money their skins bring in the market doesn't strike me as quite right. I'd never see a lady wearing a fur coat again without feeling queer, like all the innocent little animals I'd gone and slaughtered were parading before me. Nixey for mine, I give you my word."

Elmer did not make any reply in words, but the satisfied glance he gave the speaker was eloquent enough. Truth to tell he was well pleased with the change that was working in Lil Artha. At one time the tall scout had shown signs of becoming so infatuated with hunting that quite a savage desire to slay things had begun to manifest itself in his disposition. Already had the mild influence of Uncle Caleb begun to make itself felt.

Zack Arnold would not be the only one benefitted by contact with the owner of the cabin. Some of the scouts would return home with new ideas concerning things. Already Elmer could see where this midwinter holiday trip was going to repay them a dozen-fold for all it cost. He was satisfied with the promising results, and would not have had things different, could the choice be his for the taking.

While they were gone Zack had tidied up the cabin after a rude fashion, considering that he did not know much about keeping things looking nice in the first place, and had only one arm to work with in the second. But it was the fact that he was beginning to take a decided interest in things that pleased Uncle Caleb, who was not slow to commend his thoughtfulness, and Elmer could see the glow that flashed into the eyes of the big guide, telling that he had already begun to desire to do that which would commend itself to his kind benefactor.

"And it's going to be all right," Elmer told himself, as he lay down later in his bunk, watching the two men who were still sitting by the fire, talking about the habits of animals, for Zack having been a guide all his life was brimfull of such lore; "he's got Zack going, and nothing can stop him now. It must give a fellow a mighty nice feeling to know that he's changed such a life, and for better things. But if we only knew all that has happened in Uncle Caleb's past I reckon we'd find that this is just one little incident in a long string."

And that night neither Elmer nor Lil Artha dreamed of keeping watch because of the presence of so desperate a character as Zack Arnold under the same roof that sheltered them. Indeed, so greatly had their opinions changed that they would have been willing to put considerable trust in the loyalty of the rough guide. His very face did not seem one-half so repulsive, now that it no longer showed the marks of passion and pain. In fact, Elmer could see where in good time Zack might turn out to be a pretty fair looking sort of a man; for once when he allowed a smile to cross his face he was rather attractive.

So the night wore away, and another day dawned. The boys, knowing that their vacation was moving swiftly along, and feeling that they must crowd everything possible into the few remaining days, had laid out a plan of campaign that would make this a busy period. And Uncle Caleb was ready to join them in any undertaking that had for its object the satisfying of their desire for rollicking fun, or their education along the line of a more intimate acquaintance with the little woods folks in whom he took such a decided interest.