He pushed Frank over the cliff also

He pushed Frank over the cliff also.

"Don't you dare touch me!" cried Sammy, getting ready to defend himself. Yet he knew he could do nothing against the angry hermit.

"I'll fix you!" cried the old man.

"You let me alone!" pleaded Sammy. "Sic him, Maybe!" he cried, to the dog.

Indeed the hunter's dog needed no urging. At the first sign of the old man Maybe had rushed at him. Now he was tugging at his coat-tails as though to stop him from pushing the boys over the cliff. But the man was strong, and paid no attention to the dog, dragging him along over the slippery snow.

"There you go!" cried Mr. Addison, and with that he shoved Sammy down into the big snowdrift.

"There!" muttered the hermit, with a hard smile on his wrinkled face. "Now I guess them boys won't find out my secret!"

And he walked away into the woods, the dog barking after him.

As for the Fairview boys, they were more frightened than hurt. True, they had been pushed down some distance, but they fell into a soft bank of snow, and, except that it got down their necks, and up their sleeves, as well as into their boots, they were in no danger. It was like falling into a feather bed.

"Whew! What happened?" gasped Bob, floundering about.

"I guess we happened—or it happened to us!" said Frank. "Where's Sammy?"

"Here I am," cried that small hero. "He pushed me, too."

"Say, he ought to be arrested!" exclaimed Bob, angrily, as he flopped about in the snow. "What did he do it for?"

"Said we were following him," answered Frank, as he wiped the snow out of his face.

"Well, I guess we were, all right," admitted Sammy. "But he had no right to be so mean."

"Where did he go?" Frank wanted to know.

"I—I didn't stop to look," admitted Sammy. "It all happened too quick for me."

"Same here," laughed Bob. "Now I wonder if we can get out of here?"

It was not as easy as it seemed at first, for the little valley into which the boys had been pushed by the angry hermit was filled with snow, and they sank in it above their waists.

But they floundered on, and were slowly making their way out. They were getting quite tired, however, and might have sunk down in the snow, and have taken severe colds, had their struggle lasted too long.

Suddenly Bob cried out.

"Hark!" he called.

"It's a dog barking," said Sammy.

"Yes, and it sounds like Maybe," added Frank.

"See, there he is!" cried Sammy, "and he's got someone with him!"

"It's Mr. Jessup! Hurray, now we're all right!" yelled Bob, with delight. "Now we'll show that hermit what's what!"


CHAPTER XIII HELPING THE HERMIT

Mr. Jessup, with his dog floundering in the snow ahead of him, came toward the boys, who were still stuck in the snowbank, though slowly getting out of it.

"What's the matter?" cried the hunter. "What happened to you? You ought not to go in a place like that!"

"We couldn't help it!" exclaimed Sammy, with a laugh. "We were pushed in!"

"Pushed in?" exclaimed Mr. Jessup. "What in the world do you mean, Sammy?"

"Help us out, and we'll tell you," suggested Frank. "We're tired out trying to wade through the deep snow."

"I guess that's right," admitted Mr. Jessup. "I had better be helping you instead of talking. Come on, Maybe!"

With big strides the hunter came on. To him the drift gave little trouble, though for the small boys it was all they could do to wade through. But now they had help.

Mr. Jessup had a pair of snow-shoes strapped to his back, though the crust was not thick enough to allow him to use them. They would come in useful as snow shovels, though, and he at once took them for that purpose.

"Here you go!" he cried to Bob, who was nearest him. "Catch one of these shoes and help dig a path. I'll dig one to meet with yours, and when you get out here, where the snow isn't so deep, you'll be all right."

"Hurray!" cried Sammy, glad that everything was more pleasant now.

"Is your sister better?" asked Frank, while Bob used the snow-shoe as a shovel, the hunter doing the same with the one he had.

"Yes, much better," was the answer. "I was sorry I had to stay away all night, and I kept thinking, up to the last minute, that I could get off and come back to you. That's why I didn't send anyone to keep you company.

"And finally, when my sister was well enough for me to leave her in the care of some neighbors, it was too late to start for Pine Island. But I made up my mind that you boys would be all right, and I didn't worry. You were all right, weren't you, except for what happened to you just now?"

"Yes," said Sammy, eager to tell the story of the mysterious hidden room, and the strange things in it, "yes, we're all right. Nothing happened during the night, and we got along fine. Maybe was good company."

"I thought he'd be, and that's why I made him stay when I was called away," said the hunter. "But he did want to come with me."

While the boys and Mr. Jessup were talking he and Bob used the snow-shoes as shovels, so that, in a few minutes, the boys were out of the drift, and on level ground where the snow was only up to their knees.

"Now then," said Mr. Jessup, with a grin, as he looked at them, "I'm ready to hear your story. How did it all happen, and who pushed you into the drift?"

"The hermit!" cried the three boys at once.

"What! You don't mean Mr. Addison?" asked the hunter, in surprise.

"That's who it was," said Frank.

"Well, why did he do such a thing as that?" asked Mr. Jessup, in surprise. "I've known him for sometime, and, except that he was a bit odd now and then, he never acted that way. I always thought him quite gentle, except that he would order people away from his cabin. Did you do anything to him?"

For a moment the boys did not answer, and then Sammy, knowing that it was best to tell everything, said:

"Well, we followed him, that was all. We wanted to see if he was going to the big house."

"You followed him; that was all?"

"Yes, sir."

"And what did he do?"

"Well, he got out of sight, and we were trailing him," explained Bob. "Then we came to that cliff and we were looking over, down into the pile of snow, when, all of a sudden——"

"He rushed out on us from the bushes," continued Frank, "and he——"

"Pushed us down, one after the other," said Sammy, taking up the story. "And he said he'd teach us to follow him and try to find out his secret."

"Hum, he said that; did he?" mused Mr. Jessup. "Well, I'm afraid he must be out of his mind. I've been thinking that for some time, and now I'm sure of it. He must be crazy, or he wouldn't do such a thing as that. He must have been quite angry at you, and it's lucky he did nothing worse than shove you into a snowbank.

"Now I advise you boys not to go near him again. If you see him as you walk about the island, don't notice or speak to him. That will be the safest way. So you followed him, and he thought you were after his secret; eh? He hasn't any secret, as far as I know. Poor old man, he certainly must be crazy. I'm sorry for him. But, boys, did you have any special object in following him?"

Again the three chums looked one at the other.

"You'd better tell, Sammy," said Frank, at last, "you made the find, you know."

"What's this?" asked Mr. Jessup, in some surprise. "Have you boys a secret, too?" and he looked curiously at them, while Maybe frisked about, barking and unable to understand why his master would not take after a rabbit he had driven from its burrow.

"Yes, we did find something strange in the old house," said Sammy. "We discovered a secret room, and in it is an outfit of counterfeiters, Mr. Jessup!"

"And they shot at us!" cried Bob.

"And you ought to have seen the smoke!" added Frank.

The hunter looked from one to another of the boys, as if unable to understand what they were saying. He might have thought they were playing a joke on him, but their faces were too serious for that.

"Secret room!" he murmured. "Counterfeiters! They shot at you!"

"Yes, and we thought the hermit might be the counterfeiter, so we were following him to see if he went to the old house," said Bob.

"Whew! This is getting worse and worse!" exclaimed the hunter. "I guess you'd better begin at the beginning, boys, and tell me all there is to tell. Old Mr. Addison a counterfeiter! I can't believe it."

"This is the way it was," began Sammy, and then he told of the exploration of the old house, after the hunt of the day before, and how, most unexpectedly, he had pressed on the spring that opened the panel or door of the secret room.

"And you should see the things in it!" put in Bob, as by turns the boys described the queer instruments.

"And then that flash and boom!" cried Frank. "It was terrible!"

"It must have been," admitted the hunter. "But I own up that I am puzzled. I never knew there was a secret room in the old house, and I thought I'd been all over it. As for those things you tell about—well, I guess I'll have to look at 'em myself."

Mr. Jessup did not say so, but the truth of the matter was that the boys had talked so fast and so excitedly, and had interrupted each other so often, that they had not given a very clear account of the things they had seen. Then, too, as is the case not only with boys, but with grown-ups, no one ever sees the same thing the way another person would.

The boys gave as good descriptions as they could of the queer objects in the secret room, but each one put in something a little different, until it was no wonder that Mr. Jessup was puzzled.

"Now I'll tell you what," he said. "We'll go back to Camp Mystery and figure this thing out. I guess I didn't name it out of the way when I called it 'Mystery,' for it's more mysterious than ever now.

"But we'll get to the bottom of it sooner or later. I'll have a look at the things in that room. Maybe I can find out who has been taking my grub. You weren't troubled while I was away last night! were you?"

"No," answered Sammy, "nothing happened. We slept fine."

"I thought you would be all right," went on the hunter. "I came skating over to the island a little while ago, and went right to my cabin. You weren't there, but pretty soon in came Maybe, and he acted so strange that I was afraid something had happened to you. He pulled at my coat, and would run on a little way, and then stop and bark, just as if he was telling me to follow him, and he really was, as it happened."

"He must have gone for help for us!" cried Frank.

"That's what he did," replied the hunter. "He led me right here, and I can tell you I was a bit scared when I saw you floundering in the snow. I'm glad you're all right."

"Sure we're all right!" cried Sammy, "and I'd like to go to the old house right away, and find out what all those things mean. If that is a counterfeiting den we can have the men arrested; can't we?" he asked.

Mr. Jessup laughed.

"Well, Sammy," he said, "of course if there are counterfeiters here they ought to be taken in, I s'pose. But I never heard of any, and there's been no bad money circulating around Pine Island or Fairview, as far as I know."

"I told him they weren't counterfeiting things," said Frank.

"You just wait!" exclaimed Sammy, mysteriously. He was sure his find was going to turn out big this time.

"Well, we'd better get back to the cabin and prepare to look into this thing," suggested the hunter. "I want to think it over a bit. By the way, was there any sign of anybody having been in that room lately?"

"You couldn't tell—the bed looked as if it had been slept in," said Bob. "But there must have been someone hiding there, or else how could he have shot at us?"

Mr. Jessup shook his head.

"I'll admit it's a puzzle, so far," he said. "But after I see it I may be able to explain it all. Come along."

They headed back for the cabin, the boys talking on the way of the many things that had happened since coming to Pine Island. Mr. Jessup said he had heard no special news in Fairview. He had not sent any word to the parents of the three chums, fearing they would worry about the boys staying alone all night.

"And it turned out better that I did not," he said.

They were nearing the cabin of Camp Mystery, and Mr. Jessup was pointing out to the boys a trail that led from his place to the cabin of the hermit.

"But I wouldn't advise you to follow that trail after dark, unless you know it pretty well," he said.

"Why not?" asked Bob, always looking for reasons.

"Because that bog, that I told you about, is on both sides of the trail at certain places, and it's dangerous. I often wonder why old Mr. Addison built his cabin so near the bog. It's true there are some good springs of water near it, but I'd rather be on higher ground, and carry my water a way. So don't travel that trail except in daylight, boys."

They promised to be careful, and walked on, looking curiously back toward the dangerous bog.

Suddenly Frank, who was in the lead, raised a hand to order a halt and silence.

"What's up?" asked Sammy.

"Listen!" said Frank.

All heard a deep groan.

"Someone's there!" exclaimed Bob, pointing to a clump of bushes just ahead, and to one side of the trail.

"Maybe it's a—bear!" faltered Sammy.

"Nonsense!" exclaimed Mr. Jessup. "That's a human voice. Hello, there!" he cried. "Who are you? What do you want? Has anything happened? Answer!"

"Maybe it's the counterfeiters," whispered Sammy.

The dog was barking excitedly.

"Come here!" commanded Mr. Jessup, and then, as the groan sounded again, he went forward. Parting the bushes he looked ahead and cried out:

"Boys, it's Mr. Addison—the hermit, and he seems to have fallen and hurt himself! Come here and we'll help him!"

The three rushed forward. There on the ground, under the bushes, where there was no snow, lay the old man. He seemed to be unconscious and it was his queer breathing that made the groaning sound.

"Boys, see if you can't get him out of there, into a more comfortable place," said Mr. Jessup. "I'll run to the cabin for a folding stretcher I have, and I'll also get some medicine. See if you can get him out. I'll be back in a few minutes."


CHAPTER XIV THE BOILING SPRING

Mr. Addison was a full-grown man, but he was quite old, and not very heavy. In fact he was so light that the three sturdy boy chums easily carried him out from under the bushes to a cleared place along the path. The hermit only moaned as he was moved, and remained unconscious.

"Let us take off our coats, fellows," suggested Sammy. "We'll spread them out on the snow, and make a bed for him."

The day was quite warm, so the boys would not be likely to take cold from removing their coats, and soon they had made a more comfortable place for the aged man than the bare ground on which he had fallen.

"I wonder what could have happened to him?" said Bob.

"He must have fallen, and hurt himself," spoke Frank. "But neither his arms or legs are broken, as far as I can tell."

"I guess it's his head," remarked Sammy. "Probably that's what makes him senseless. I wish Mr. Jessup would hurry back."

"And to think that a little while ago he pushed us into a snowbank!" murmured Bob. "He couldn't do it now."

"No," said Sammy, softly. "Poor old man! I guess he's had lots of trouble."

Indeed, as the aged hermit lay there on the boys' coats, which they had partly folded over him, his face showed many wrinkles of care and suffering, as well as of age. Truly, he did not seem to have had a very happy life, and in their hearts the boys easily forgave him for what he had done to them.

"Here I am!" exclaimed Mr. Jessup, as, followed by his dog, he came up the path. Over his shoulder he carried a folding stretcher, consisting of two poles with a broad canvass piece in between. On this the hermit could be placed, and, by means of the handles, he could be easily carried.

"I'll give him a little spirits of ammonia first," said the hunter. "That is good when a person has fainted. Then we can decide what next to do. It may be that we'll need a doctor."

He mixed some of the ammonia in a glass, with a little water, and managed to get some between the lips of the old hermit. But it did little good. The aged man only moaned feebly and did not open his eyes.

"I guess we'd better carry him to his cabin," said Mr. Jessup, after a few minutes. "It's farther than it is to Camp Mystery, but if he wakes up, and sees himself in a strange place, it may have a bad effect on him. We can easily carry him to his own cabin."

This they did, the hunter taking one end of the stretcher, and two boys taking turns at the other end. In this way they were soon at the place where the hermit lived.

The cabin was rough enough on the outside, but the interior was clean, and nicely arranged. The poor old man lived very simply. He was placed on his bunk, and then Mr. Jessup, who knew a little about medicine, tried to bring him to his senses.

It seemed to be of no use, however, and finally the hunter said:

"Boys, I think I'd better skate over to the mainland, and bring back a doctor. I wouldn't like poor Mr. Addison to die. You're not afraid to stay here with him; are you? I'll leave Maybe with you."

"Afraid? Of course not!" cried Sammy. It was broad daylight. Why should they be afraid?

True, the mysterious old mansion was not far away, and the strange things in the secret room had not been explained. But the boys made up their minds they would not be alarmed.

"I'll come back as soon as I can," said Mr. Jessup. "If he wakes up you might give him a drink of water. Or you could make coffee. You know how, and I see he has the things here. Yes, a good strong cup of coffee might help him. Now don't worry. Maybe, you're to stay with the boys."

The dog whined, and evidently wanted to go with his master, but he obeyed well, and, with a bark of protest, he lay down on the cabin floor.

Mr. Jessup, who had his skates with him, started for the lake, intending to skate to the mainland after a physician. He could come back with the doctor in a cutter, for the ice was thick enough to bear the weight of a horse.

Left to themselves, the boys sat in the cabin with the old, unconscious man. He breathed heavily but did not open his eyes. Once in a while he groaned.

"I wonder if we hadn't better make the coffee," suggested Bob, after a bit. "If he could take some of that he might feel much better."

"Good idea," said Sammy. "Let's start a fire. It's cold in here, anyhow."

There was a stove and an open fireplace, the latter in the other room of the cabin. Some logs were set aglow on the hearth, and a roaring blaze kindled in the stove. The kettle was put on, and soon a fragrant pot of coffee was ready.

The kettle was put on

The kettle was put on.

The boys were talking over whether they had better not try to get some of the hot beverage between the set lips of the aged man, when there came a sudden knock on the cabin door.

"Who's that?" whispered Frank, startled.

"It can't be Mr. Jessup, back already," remarked Bob.

"No, he'd walk right in," said Sammy.

The knock was repeated.

"See who it is," spoke Bob.

"I'll go," said Sammy, and he went to the door.

He saw a young man standing there—a young man he had never seen before, as far as he knew. The stranger's face was a pleasant one, and he smiled at the boy.

"Well," said the visitor, "I don't know you, and it's rather odd to see Mr. Addison having company. Is he in?"

"Yes," said Sammy, "but he's hurt." He noticed that the caller had a pair of skates in his hand, showing how he had reached the island.

"Hurt!" exclaimed the young man. "And just when I come to bring him good news! Let me see him, please."

He quickly entered the cabin, and bent over the form of the hermit on the bunk. The boys looked on in wonder. Who could this stranger be?

The young man seemed to know something about the duties of a doctor, for he rapidly felt about the aged man, for signs of broken bones, and then, finding none, passed his hand over the sufferer's head.

"Ah, there's the trouble," he said. "He's had a bad knock there, but it doesn't seem to be serious. I think he'll soon come around. You have coffee?" and he sniffed the air.

"Good and hot!" answered Sammy.

"Let me have some," suggested the young man, and some was given him in a cup. Holding the aged man up in one arm, the young man managed to get some of the hot coffee down his throat. It did good at once, for Mr. Addison opened his eyes, looked strangely about him, gazed in seeming wonder at the boys, and then looked at the young man who was supporting him.

"It's all right, Uncle Frank," said the stranger. "You're all right. You had a little fall, and these boys must have brought you here. But you're not hurt to speak of, and I bring you good news."

"Good—good news," faltered the old man. "You bring me good news, Ed?"

"Yes, the very best. The land is now yours. I have here all the papers. You don't need to live here any longer to claim it. You can come home with me. I have the deeds to the land."

"And the spring—the boiling spring—is the medical spring mine?" gasped Mr. Addison. He seemed to be getting better very quickly.

"The boiling spring is yours," the young man assured him. "Now take it easy—everything is all right."

"Oh, I am so glad—so glad!" murmured the old man, sinking back on the bunk. "Now I won't have to worry about anyone taking my secret away from me. Oh, everything is all right now," and he sighed in contentment.

"Take a little more coffee," urged the young man whom the hermit had called Ed. "It will do you good."

It really seemed to, for soon the aged man was able to sit up again.

He looked at the boys strangely, and they did not know what to do or say. They wondered if the hermit would try to drive them away.

"Are—are you the boys I pushed over the cliff?" he asked.

"Yes," replied Sammy, and he wondered how the old man could explain his queer action.

"Well, I—I'm sorry I did it," went on the hermit. "You see I was a bit excited. I thought you were following me, trying to steal my secret. But you can't get it now. I own the land. You have the papers—the deed, Ed?" he asked eagerly.

"Yes, Uncle Frank, here they are," and the stranger gave a bundle of documents to the old man, who eagerly looked them over.

"Yes—yes," he said. "It's all right. I have a clear title to the boiling spring. And now I'll explain. But in the first place, how did I get here? I seem to remember falling down——"

He paused for an answer.

"You did fall," said Sammy. "Mr. Jessup and we boys found you under the bushes, and we carried you here. He has gone for the doctor."

"Hum, yes. That's very good of him—and you, especially after the way I treated you. But I hardly knew what I was doing. But I don't believe I need a doctor. I'm all right."

He really seemed so, and was able now to walk slowly about the cabin.

"I remember what happened," he went on. "I was going down to the shore to see if you were coming, Ed, for you had promised to be here to-day, when I slipped and fell. I must have struck my head on a stone, for it all got dark, and I didn't remember anything else until I saw you giving me coffee. All the rest is a blank."

"Well, you're all right now, Uncle Frank," was the answer. "I suppose I'd better tell you who I am," the newcomer went on to the boys. "My name is Edward Houghton, and Mr. Addison is my uncle. I have been doing some legal business for him for some time, and now it is all finished."

"And the medical boiling spring is my property!" cried the hermit.

"Yes, it is your property," said his nephew.

"And you and I will get rich!" the old man cried, enthusiastically.

"I hope so," spoke Mr. Houghton. "You certainly have suffered very much to get your rights. But it is all over now."

The boys were quite puzzled by this talk, but it was soon to be explained. There was the jingle of sleigh bells from the direction of the lake, and soon was heard the approach of footsteps.

"It's Mr. Jessup!" cried Sammy. And so it proved. He had brought the doctor back with him in a cutter.

"I'm much obliged to you, Mr. Jessup," said the old hermit, "but I don't believe I need the doctor's services."

"However, as long as he's here, better let him look you over," suggested Mr. Houghton.

The medical man said, beyond a hard blow on the head, which had made him unconscious for a time, Mr. Addison was not hurt.

"I'd stand another blow on the head for the sake of my fine spring," said the hermit, and he laughed.

He really seemed quite a different man now. His face was kinder, and the boys were no longer afraid of him.

"I guess you'll have to explain," suggested Mr. Jessup. "What is it all about, and what do you mean by your boiling spring, Mr. Addison?"

"Come with me, and I'll show you," said the hermit.

With slow steps he led the way to a little glade, not far from his cabin. There the boys saw a strange sight. In spite of the fact that it was Winter, and that snow was on the ground, there was a spot of green grass and ferns to be seen, surrounding a boiling and bubbling spring of clear water. And from the water a little cloud of steam arose.

"There she is!" cried Mr. Addison. "There's my boiling spring, and the waters of it are the best thing in the world for rheumatism. I know, for I've cured myself, and cured others. I discovered the spring by accident, and I worked hard to get title to the land it's on. Now I have it, and I'm going to bottle those waters and sell 'em. I'm going to be rich! I'm not going to be a hermit any longer," and he seemed ten years younger.


CHAPTER XV THE END OF CAMP MYSTERY

"Well," said Mr. Jessup slowly, "this may be all clear to you and your nephew, Mr. Addison, but it's like Greek to me. If you wouldn't mind explaining——"

"Of course I'll explain," said Mr. Addison eagerly. Sammy hoped something would be said to clear up the mystery of the strange room in the old mansion.

"First of all," said the hermit, "I want to tell you boys how sorry I am that I pushed you into the snow. I was all excited when I saw you following me, and I really didn't know what I was doing. You see I had been expecting my nephew for some time, and when he didn't come I was afraid something had happened so that I couldn't get the spring I had tried so hard for. So first I want to beg your pardon."

"Oh, that's all right," said Sammy, easily. "It was as much our fault as it was yours. We had no right to follow you, and really we weren't hurt a bit."

"I'm glad of it," said the old man. "Well, to begin at the beginning. Some months ago, when I was walking over this island, I found this boiling spring. It was in a place few people would visit, and I guess that's why it was never talked of before. For a good many years I have had the rheumatism, and I've tried all sorts of cures. Just by accident I thought of trying this spring water, as I could easily tell that it had some sort of medicine in it.

"I took some home, and in a few days after taking it I felt better. Then I made more tests, and I was sure I had found a cure for some of the worst kinds of rheumatism. Then I decided to try to get possession of the land on which the spring was.

"This was not easy, as the title was in dispute. But I got my nephew to help me. In order that no one else would claim the spring, I decided to put up a cabin near it, and live on the land until I could buy it. This I did, and I became a sort of hermit. I was so afraid someone would discover the secret of the spring that I drove away anyone who came near. In that way I suppose folks began to think I was crazy, and a sort of crank.

"But I did not care. I wanted to get title to that spring, for I knew I could sell the waters and get rich. And now I can. My nephew has brought me the final papers, and the spring is mine. I am going to form a company, and bottle the boiling water. Of course it won't stay hot, but it will be just as good, for it can be heated before being swallowed.

"So I'm no longer the hermit of Pine Island. I'm going back where I belong, and I'll let others do the work. And I'll say this, Mr. Jessup, if ever you get the rheumatism you can have free all the water from my mineral spring that you want."

"Thank you!" said Mr. Jessup, with a laugh, "but I hope I'll never have the rheumatism. But if I do I'll use your spring water."

"I had a hard time getting the final papers," said Mr. Houghton, "and that's what took me so long. But now, Uncle, the boiling spring is yours, and you needn't worry any more."

"How can it be hot water in the Winter time?" asked Bob.

"Well, that's one of the mysteries of Nature," said the former hermit. "I suppose the waters must come from deep down in the earth, and the wise men tell us that inside the earth are raging fires. I don't know about that, but I do know my medical spring will cure rheumatism. And I guess now, everything is explained."

"No, not everything," said Sammy quickly.

"Eh?" asked the old man.

"We found a secret room in the old mansion," went on Sammy, "and it's a counterfeiters' den, I'm sure. We thought you were going there, Mr. Addison, that's why we followed you.

"And while we were in there," Sammy went on, "there was an explosion. We thought someone was shooting at us, and we ran out. That has to be explained yet."

"That's so!" exclaimed Mr. Jessup. "I've got to look into that."

Mr. Houghton laughed.

"It won't take much of an explanation to do away with that mystery," he said. "If you'll come with me I'll show you all about it. I fancy you stumbled across one of my fads. Will you come, Uncle Frank?"

"No, I'll go back to my cabin," was the hermit's answer. "I'm going to pack up and go back to the mainland to live, now that my medical spring is safe."

"Then the rest of us will go," suggested the young man.

They left the little glade where the hot spring made grass grow in the middle of Winter, and soon reached the hermit's cabin again. He went in there, while Sammy and his chums, with Mr. Jessup and Mr. Houghton, kept on to the deserted mansion, telling the hermit they would soon be back to look after him. The doctor, whom Mr. Jessup had brought, had gone back to the mainland in his cutter.

"Shall we go right in?" asked Sammy, when Mr. Houghton and the others reached the old house, and prepared to enter.

"Of course—why not?" inquired the young man, with a smile.

"Well, I was thinking that the counterfeiters——"

Mr. Houghton laughed.

"I'll explain all that," he said.

The place of the secret room was soon reached. It was just as when Sammy and his chums had rushed away from it after the explosion that had so frightened them. The sliding door was still wedged back with the piece of shutter.

Mr. Houghton went over to the table on which was piled the strange apparatus. He moved some of the wires and springs.

"Look out!" cried Sammy. "You may get shot!"

"No danger!" laughed the young man. "I fancy you boys set off the flashlight, and there isn't another."

"Flashlight!" cried Sammy.

"Yes, that was what made the smoke and explosion," said Mr. Houghton. "You touched the spring that worked the electric battery, and the current set off some flashlight powder in a box. It did make quite an explosion, I fancy."

"But what was flashlight powder doing up here?" asked Mr. Jessup.

"I was trying to get some night photographs of bats," explained Mr. Houghton. "You see all this apparatus is just some photographic cameras, set to work automatically. I fancy I have the pictures of you boys on the plate, instead of the bats," and he smiled at the three chums.

"Photographs!" cried Sammy.

"Cameras!" exclaimed Bob.

"Aren't these things telescopes?" asked Frank.

"And isn't there any counterfeiting plant?" Sammy wanted to know.

"Nothing half as sensational as that," answered Mr. Houghton, with a hearty laugh. "This is only my new apparatus for having animals take their own pictures."

For a moment there was silence, and then Sammy, in a queer sort of voice, murmured:

"Stung again!"

All his mystery had vanished into thin air.

"Make animals take their own photographs; eh?" said Mr. Jessup. "That's rather odd."

"Oh, it is often done," said Mr. Houghton. "All you have to do is to set your camera in the woods after dark, near where you have noticed marks of a raccoon, muskrat or other wild animal. You put a string across the path the animal usually takes, and in the dark it runs into the string and breaks it. This sets off a flashlight which makes the place as light as day. The breaking of the string also opens and closes the shutters of the camera, and so the animal takes its own picture. I've been doing it for some time, and had good results. I left my cameras, flashlights, batteries and so on here, in the hope of getting pictures of bats, but I guess I'll have to try again."

"So that's what it was that exploded," said Sammy—"flashlight powder?"

"That was it," said Mr. Houghton. "You see I happened to discover this secret room by accident. I was going through the old mansion one day, thinking it would be a good place to get bat pictures, and I found the secret chamber. So I fitted it up as a room where I could sleep when I had to. Often I would take my cameras out in the woods and leave them there until nearly morning. Then I would get up and go bring them in. I did not want to disturb my uncle so I stayed here. I fancy the secret room must have been built by the man who put up the old mansion, for his own use."

"I think so," agreed Mr. Jessup. "He was a queer character anyhow. And to think I've been in and out of the old place so much, and never found the secret room!"

"It was pretty well hidden," said Mr. Houghton. "Well, I don't imagine I'll use it any more. I'll try for bat pictures somewhere else. Besides, if my uncle's mineral spring turns out as well as he thinks it will, this place may become a Summer resort, and the old mansion could be made into a hotel for people who want to take the rheumatism cure."

"But there's one thing I don't understand," said Mr. Jessup, "and that is who took my grub."

"I think I can explain that, too," spoke Mr. Houghton. "I had hired a young man to assist me, in my photographic work, but when I found out he was not honest I discharged him. I saw him come along one day with a strip of bacon, and a long pole with a hook on the end. He said he had hooked the bacon."

"And so he had!" cried Mr. Jessup. "That was one of the pieces I missed."

"The fellow must have stood some distance away from your cabin, and caught the string of the bacon in the hook on the pole," said the photographer. "That's why you never saw any footmarks."

"Then this is the end of Camp Mystery," said Sammy, faintly.

"That's right!" cried Frank. "I told you there weren't any counterfeiters."

"Well, there might have been," returned Sammy.

And he wondered why the others laughed.

But it was really the end of Camp Mystery. The hermit's secret had been the warm, medical spring, and now that he had full title to it he need not worry any more, nor drive away those whom he thought might try to cheat him out of the property.

Mr. Houghton had explained the queer machines in the secret room, and had told how he used to photograph wild animals at night. A few days afterward he showed the boys how he set the cameras in the wood, with a string which the animals themselves would break, thus setting off the flashlight and taking their own picture.

Mr. Jessup made some inquiries, and found out that the secret room in the old mansion had been built by the former owner of it. He had no particular use for it, but it was just a notion on his part to have it made. Mr. Houghton had accidentally discovered it, just as Sammy had done.

As for the young man who had taken things from Mr. Jessup's camp, he was not heard of again. After all, he had not taken a great deal, and his plan of using a long pole with a hook on it explained why he had never left any marks. He could reach in the window or door of the cabin when Mr. Jessup was away, and get what he wanted. He had been in the habit of staying in the secret room when Mr. Houghton did not sleep there.

"Well, as long as everything is explained, we may as well go back to camp," said Sammy, when they left the old mansion.

"Yes, I guess so," agreed Mr. Jessup. "You boys are entitled to some fun after your hard work."

"Yes, and they're entitled to more than that," said Mr. Addison, a little later. "I owe them something for helping take care of me," and some time afterward, when the Mineral Spring Company was formed, he sent each of the boys a nice present.

"Well, now we'll take it easy," suggested Sammy, when they got back to the hunter's cabin, late that afternoon. "We'll go skating and coasting, and——"

"Fishing through the ice," added Mr. Jessup. "I've had that in mind for you for some time."

"Say, this trip to Camp Mystery is all right!" cried Frank, with a laugh. "I wonder if we'll have as much fun as this next Winter?"

"More I hope," said Sammy. "But Summer will come before Winter."

And what the chums did the following Summer may be learned by reading the next volume of this series, to be called "Fairview Boys at Lighthouse Cove; Or, Carried Out to Sea." In that we will meet all our young friends again.

In the days that followed Sammy and his chums had many good times. They roved about the island with Mr. Jessup and watched him at his hunting. They had many good meals, too. Mr. Addison left Pine Island, now that he had possession of the spring, and one of the members of the company he had formed took up a residence in the cabin. But there was no further trouble. The mystery had been solved.

"Come on for a skate!" cried Bob, one afternoon. "We only have a few more days here."

"That's right—and then school once more!" exclaimed Sammy.

And as the Fairview Boys are starting off on the glittering ice, we will take leave of them.