CHAPTER XXXIV

THE MYSTERY EXPLAINED

Jack opened the cabin door, and stood in it, prepared to greet Will. The other captives gathered back of their chum.

"How are you, Will?" asked Jack, as soon as his friend came within speaking distance. "We were quite worried about you."

"I'm all right," answered the strange lad.

"Why did you run away?" inquired Sam, while Nat looked closely at Andy. The man had a good-natured, smiling face, and Nat's spirits began to rise. He did not think they had much to fear from such a man.

"It's a strange story," said Will, as he entered the cabin, followed by the man.

The boys crowded around the two, and waited anxiously for Will's next words.

"First," began the lad, who had acted so strangely, "let me introduce to you my uncle, Mr. Andrew Swaim."

"Your uncle!" exclaimed Jack.

"Your uncle!" echoed Sam, Bony and Nat.

"That's right. My uncle, whom I ran away from home to seek," went on Will. "I never expected to find him here."

"Nor I to see my nephew," explained Mr. Swaim. "I was never more surprised in my life than when he ran to me in the shed. After he had called me by name, he fainted dead away. He has been unconscious all night, and only a few minutes ago did he come to his senses. I remained at his bedside all the while. As soon as he roused, and felt better, he told me about coming here with you boys, and insisted that I come out to look for you. That was the first I knew you were still in my camp. I hope you haven't suffered any inconvenience. I saw you as I was about to open the shed doors, but I supposed my men warned you away. I hope you are not angry."

"Not much," replied Jack with a smile. "And so Will fainted as soon as he greeted you?"

"Yes. He explained later that he got a blow on the head, and that, together with the thrilling ride down the mountain, on top of the worry he had sustained in searching for me, and other hardships he had undergone, made him go temporarily out of his mind. But he is all right now, he says."

"Yes, that's what I am," said Will. "All my troubles are over, now that I've found my uncle. What did you think, when I ran away?"

"We didn't know what to think," replied Jack. "Especially when you didn't come back."

"This is how it was," explained Will. "I saw my uncle as soon as he began opening the big doors the second time. Before I knew what I was doing I had run toward him, and when I was near enough I called his name, and told him who I was. He recognized me at once, and----"

"Yes, and I saw that he was about to keel over," interrupted Mr. Swaim. "I caught him in my arms, carried him inside the shed, and I had my hands full all night with him. I had given orders to my men never to enter that shed except on certain occasions. They did not disobey my instructions to tell me you boys were still here, and, of course, Will could tell me nothing until this morning. Then he insisted that we come out and find you. I called in Stephen----"

"Is that the red-haired man?" asked Jack.

"He is. I called him in, and he explained about you being in this cabin. And now here we are--Will and I, and I can't thank you enough, Jack Ranger, for what you did for him. He has told me a little about it, and how kind you were to him in school. I shall have a score to settle with that rascally guardian of his. I never suspected Gabel could be so mean. But his charge of my nephew is ended. I will make other provisions for Will. Are you boys all right now? Did you have some breakfast?"

"Oh, yes," replied Jack. "If we had known that Will's uncle was in charge of this camp, we wouldn't have----"

"Now don't make any apologies," interrupted Mr. Swaim. "It's all right. I want you to make yourselves right to home here. My regulations were only intended for men who might try to spy on my work. For I am perfecting a means----"

"Fellows, you'll never guess what the mystery is," burst out Will. "Excuse me, Uncle Andy," he went on, "but let me tell them. You see we've puzzled over it so long, and none of us could guess. Jack, Nat, Sam, Bony--what do you think it is that my uncle has in the big shed--the thing that flew over our camp and scared Long Gun so? See if you can guess."

"A great bird--like the roc of the Arabian Nights," said Nat.

"No."

"Some sort of eagle, larger than any ever seen in these parts," ventured Sam.

"No, that's as far off as Nat was."

"A kite, carrying an engine, working a camera, for taking moving pictures at night," was Bony's guess.

"No," said Will. "It's your turn, Jack."

Jack thought for a minute. He glanced at the big shed, and then started, as a sudden idea came to him.

"A balloon?" he asked.

"No, but you're nearest to it. Shall I tell them, Uncle Andy?"

Mr. Swaim nodded.

"It's a great aeroplane!" exclaimed Will.

"An aeroplane!" exclaimed all the other lads in a breath.

"A new form of aeroplane, with propellers built like the great wings of a bird," explained Mr. Swaim. "It's an invention of mine, but is not perfected yet, though it flies fairly well. There are certain parts, on which I have not yet got my patents, and that is why I do not admit any of the men to the shed when the '_Eagle_' as I call her, is there. But Will got in before I could stop him, though I guess he'll not try to get ahead of his uncle."

"No, indeed, Uncle Andy!"

"And did you fly it over our camp?" asked Jack.

"I did, and that was the sound you heard. It makes quite a whirring noise, when the wings are working fast, and the engine has a peculiar throbbing sound. I don't wonder you and the Indian guide were frightened."

"Oh, Long Gun was more scared than we were," explained Nat.

"Probably. You see I only flew it at night, because I did not want any one to see it."

"And it really works?" asked Bony.

"Yes, but not as well as I would like it to. I have only been able to take up myself and one other man, so far. I want it to carry at least five passengers, but I shall have to alter my engine, or change the shape of the wings, or else increase their size, before it will lift that much. But Stephen and I often flew over the mountain. We used to judge of our position by your camp-fire. At least I suppose, from what Will tells me, that it was your fire."

"Yes," said Jack. "We heard you calling to one another one night, and that kept us guessing more than ever."

"What about those queer marks in the snow?" asked Bony.

Mr. Swaim looked puzzled until Jack explained.

"Oh," said the inventor, "that was when we had an accident. The _Eagle_ came down unexpectedly, and turned turtle. Neither I nor Stephen was hurt, but we had quite a time righting the machine. The marks you saw must have been the impressions of the wings in the snow."

"We thought it was a great bird," explained Nat.

"And I wasn't so far out, calling it an eagle," spoke Bony, cracking a couple of finger knuckles, and ending up with both thumbs.

"I have been out here in this secluded place for several months," went on Mr. Swaim. "That is why I left no address for my nephew's guardian, as I did not want to be disturbed. I never supposed my nephew would try to find me, and he probably would not have done so, except by accident. But I will soon go back East, for my invention is almost perfected, and I want to give some exhibitions, and try for some government prizes. Would you boys like to see it tried?"

"You bet!" exclaimed Jack fervently, and the others nodded assent.

"We were going to give it a trial when you boys arrived here," went on Mr. Swaim. "Now that Will is all right, I think I will take the _Eagle_ out for a flight. I was considerably worried," he continued, "when my men brought me reports of strangers trying to enter the camp, and I gave strict orders to keep them out. That is why my men were rather brusk with you."

"That's all right," answered Jack. "We had no right to come around, but we were very curious."

"I don't blame you. Well, I'll go and get the machine ready for a trial spin."

"Excuse me for mentioning it," said Jack, as Mr. Swaim prepared to leave the cabin, "but you have a chap here named Jerry Chowden? My friends and I used to know him."

"Is that so?" asked Mr. Swaim in some surprise. "I know little about him. He came to me one day, and asked for work, saying he needed money. As I was short of help I took him on, but I am sorry I did so, for my foreman tells me he is not worth his salt, and is lazy in the bargain. He never said anything to me about meeting you. I shall get rid of him, I think. Is he a friend of yours?"

"Well, I guess not!" exclaimed Jack heartily.

"I'm glad of it, for I don't like his manners. Now I'll go and see about taking the ship out. Will may remain with you."

The boys had plenty to talk about now. Their exchange of experiences of the incidents of the last few hours was interrupted by the appearance of the great aeroplane, as the men wheeled it out of the shed.

"Wow! Petrified pancakes!" exclaimed Nat. "That's a dandy, though!"

Indeed the _Eagle_, in spite of the fact that Mr. Swaim had said it was not completed, was a fine example of an aeroplane. The boys crowded up close to it, examining the different parts, while Will's uncle and some of his men got it ready for a flight. As they started the motor, which worked the great wings, Nat said:

"That accounts for the gasolene smell. I guess the mystery is all explained now."

"It seems so," spoke Jack.

The aeroplane was taken to the ice-covered pond, over which the sled had slid on the finish of its perilous trip.

"Is that what this is for?" asked Jack.

"Yes," replied Mr. Swaim. "We cleared the snow off it on purpose to use for our trials. An aeroplane, you know, as at present constructed, has to get a start on the ground, in order to acquire enough momentum to rise. I find it much easier to skim along on the slippery ice, than over the ground. Well, are we all ready, Stephen?"

The red-haired man, who was the chief mechanic, nodded an assent. He and Mr. Swaim got into a seat, adjusted some levers and wheels, and then another man cranked up the motor.

The great propellers, built like the wings of a bird, began to work, with a sound that was exactly like that heard over the camp. The aeroplane slid forward, and after going for some distance over the frozen pond, rose into the air, as Mr. Swaim shifted the elevation rudders.

Up, up, up it went, until it was higher than the mountain down which the boys had slid. Then it began to circle about.

"My! But that's fine!" exclaimed Jack.

"Jupiter's Johnnie cake! But it certainly is!" exclaimed Nat fervently.

For half an hour or more Mr. Swaim circled about in the air overhead; then he and Stephen came down, landing on the pond with scarcely a jolt.

"What do you think of it?" asked the inventor proudly.

"It's great!" exclaimed Jack enthusiastically, and his chums echoed this sentiment.

"Would you like to try a ride in it?" asked Will's uncle.

"Well--er--not just now," stammered Jack, and Mr. Swaim laughed.

"No, I wouldn't want you to risk it, until I have perfected it a little more, though Stephen and I have gone twenty miles in it."

One of the workmen ran up, and whispered something to Mr. Swaim.

"Is that so?" he asked, in some surprise. "Well, that simplifies matters. I have just been told," he went on, turning to the boys, "that Jerry Chowden has disappeared. I guess he did not want to meet you lads."

"I guess not," said Jack significantly.

The boys spent some time further, examining the aeroplane, and visiting the machine shop, whence came the throbbing of a gasolene engine--the same sound they had heard when on their second visit to the camp.

Jack asked Will's uncle if on any occasion he and Stephen had not landed near the camp, for Jack had in mind the occasion when the meat was stolen from the tree by the bear.

"Oh, was that your meat?" asked Mr. Swaim with a laugh, when Jack had explained. "We always wondered whom we had robbed. Stephen and I were out for a flight that night, and we had to descend because of an accident to the motor. We came down near the tree where the meat was, and surprised a bear at work getting it. Bruin scrambled down and ran away, and we concluded to take some of the meat, as we were short. Then we started the machine off again, and came here. I hope we didn't put you to any inconvenience."

"Oh, no," replied Jack. "It only puzzled us some, that was all. But have you an arrow in hobnails, on the soles of your boots?"

Mr. Swaim lifted his foot and showed the arrow.

"That explains everything," remarked Nat.

"Yes, the mystery is ended," added Jack.