Tom Swift in the Caves of Ice, or, the Wreck of the Airship

ANDY'S AIRSHIP FLIES

"Hello, Tom, have you heard the news?" asked Ned Newton, of the young inventor, a few days later.

"What news, Ned? I declare I've been so busy thinking out the best plan to ship the RED CLOUD to Seattle that I haven't been over to town. What's going on? Have they decided to build a new church in Shopton, or something like that?"

"Oh, this about Andy Foger's airship."

"Andy's airship, eh? Is he still working on it?"

"It's all done, so Sam Snedecker was telling me last night, and to-day Andy is going to try to fly it."

"You don't mean it!"

"Sure thing. Let's go over and watch him."

"He might make a fuss, same as he did when we looked in the window of his shed."

"He can't make any fuss now. He's got to take his machine out to fly it, and anybody that wants to can look on. Didn't he watch you make flights often enough?"

"That's so. Where is the trial flight going to take place?"

"In the big meadow. Come on over."

"Guess I will. I can't do much more now. I've been getting some boxes and crates made in which to pack the RED CLOUD. I'll have to take her all apart."

"Then you're really going to hunt for the valley of gold?"

"Sure thing. How about you going, Ned? I spoke to dad about it, and he said he'd see that you could have a leave of absence."

"Yes, that part's all right. The bank president told me today I could take a vacation any time I wanted it. In fact that's what I came over to see you about. I want to thank your father."

"Then you're going?"

"I sure am, Tom! Won't it be great! I hope I can get a little gold for myself! My folks didn't take very much to the notion of me going off in an airship, but I told them how often you'd gone on trips, and come safely back, so they finally gave their consent. When are you going to start?"

"Oh, in about two weeks. Did I tell you about Andy and the map?"

"No. What trick has he been up to now?"

Thereupon Tom related his suspicions concerning the bully, and also hinted to Ned of a certain ruse he intended to work on Andy when he got the chance.

"Well, if you're ready, suppose we go over and see if Andy's airship will really fly," suggested Ned, after a while. "I'm doubtful myself, and I'd just like to see him come to grief, after the many mean things he's done to you."

"Well," spoke Tom slowly, "I don't know as I wish him any bad luck, but I certainly hope he doesn't use his airship to try to beat us out in the hunt for the valley of gold."

"Do you think he might?"

"It's possible. But never mind about that now. Come on, we'll go over to the big meadow."

The two chums walked along together, talking of many things. Tom told of some communication he had had with Mr. Damon, in which letters the eccentric man had inquired as to when the trip for Alaska would be undertaken.

"Then he's going?" asked Ned.

"Oh, yes, it wouldn't seem natural to go without some of Mr. Damon's blessings. But I think he's going to bring a friend with him."

"Who?"

"Mr. Ralph Parker."

"That gloomy scientist, who is always predicting such terrible things going to happen?"

"That's the gentleman. You met him once, I believe. Mr. Damon says Mr. Parker wants to do some scientific studying in the far north, so I've already counted on him as one of our party. Well, perhaps he won't do so much predicting this trip."

A little later Tom and Ned came to a big open field. They saw quite a crowd gathered in it, but no sign of an airship.

"Guess Andy hasn't arrived," spoke Tom.

"No; very likely he's found out that something is wrong with his machine, and he isn't going to risk it."

But almost as Ned spoke, there sounded cries of excitement from the crowd, and, a little later, something big and white, with many wing-shaped stretches of canvas sticking out from all sides, was seen turning into the big meadow from the broad highway that led to Andy's house.

"There she is!" cried Ned.

"There's something, at any rate," conceded Tom, as he hastened his steps. "It's a queer-looking aeroplane, though. My! he's got enough wings to it!"

"Yes, it's Andy's sure enough," went on Ned "There he is in front, giving orders like a major-general, and Sam and Pete are helping him. Let's get closer."

They followed the crowd, which was thronging about the airship that Andy Foger had made, Tom had a glimpse of the machine. It was a form of triplane, with three tiers of main wings, and several other sets of planes, some stationary and some capable of being moved. There was no gas-bag feature, but amidships was a small, enclosed cabin, which evidently held the machinery, and was designed to afford living quarters. In some respects the airship was not unlike Tom's, and the young inventor could see that Andy had copied some of his ideas. But Tom cared little about this.

"Do you think it will go up?" asked Ned.

"It looks to me to be too heavy, and his propellers seem too small," answered Tom. "He's got to have a very powerful motor to make all that bulk fly."

The people were crowding in closer around the airship, for the news that Andy was to attempt a flight had spread about town.

"Now keep back—all of you!" ordered the bully, with a show of anger. "If any one damages my airship I'll have him arrested! Keep back, now, or I won't fly!"

"Reminds me of a little kid saying he won't play if he can't have his own way," whispered Ned to Tom.

"Hello, Andy, give us a ride!"

"Going above the clouds?"

"When are you coming back?"

"Bring down a snowstorm!"

"Be careful that you don't fall!"

These were some of the things shouted at Andy, for he had few friends among the town lads, on account of his mean ways.

"Keep quiet—all of you!" he ordered. "Get back. You might get hurt when I start the motor. I'm going to make a flight soon," he added proudly. "Sam, you come over here and hold this end. Pete, you go back to the rear. Simpson, you get inside and help me with the motor. Henderson, you get ready to shove when I tell you."

These last orders were to the two machinists whom Andy had engaged to help him, and the bully gave himself no end of airs and importance as he bustled about.

Tom could not help but admit that Andy's machine was a big affair. There was a great stretch of wings and planes, several rudders other appliances for which the young inventor could not exactly fathom a use. He did not think the machine would fly far, if at all. But Andy was hurrying here and there, getting the triplane in place on a level stretch of ground, as if he intended to capture some great prize.

"Are you going to tackle him about stealing a copy of that map?" asked Ned.

"I will if I get a chance," answered Tom, in a low voice.

He got his opportunity a few minutes later. Andy, hurrying here and there, came face to face with the young inventor.

"Hello, Andy," spoke Tom, good-naturedly. "So you're going to make a flight, eh?"

"Yes, I am, and I s'pose you came around to see if you could get any ideas; didn't you?" sneered Andy.

"Of course," admitted Tom, with an easy laugh. "My airship doesn't fly, you know, Andy, and I want to see what's wrong with it."

There was a laugh in the crowd, at this, for Tom's success was well known.

"Are you going to Alaska?" suddenly asked Tom, in a low voice, of the bully.

"To Alaska? I—I don't—I don't know what you mean?" stammered Andy, as he turned aside.

"Yes, you do know what I mean," insisted Tom. "And I want to tell you that the map you have won't be of much use to you. Why, do you think," he went on, "that Abe would carry the real map around with him that way? It's easy to make a copy look like an original, Andy, and also very easy to put false distances and directions on a map that may fall into the hands of an enemy."

The shot told. Andy's face turned first red and then pale.

"A—a false map!" he stammered. "Wrong directions?"

"Yes—on the copy you made of the map you took from Mr. Abercrombie," went on Tom.

"I—I didn't make any—Oh, I'm not going to talk to you!" blustered Andy. "Get out of my way! I'm going to fly my airship."

The bully pushed past Tom, and started toward the triplane. But Tom had found out what he wanted to know. Andy had made a copy of the map. From now on there would be every danger that the bully would make an effort to get to the valley of gold.

But other matters held Andy's attention now. He wanted to try his airship. With the help of his two cronies, and the machinists, the machine was gone over, oiled up, and finally, after several false starts, the motor was set going.

It made a terrific racket, and the whole machine vibrated as though it would shake apart.

"He hasn't got it well enough braced," said Tom to Ned.

"Out of the way, now, everybody!" yelled Andy. "Keep away or you'll get hurt! I'm going up!"

He climbed into the cabin of the craft, and took his position at the steering-wheel. The speed of the motor, its racket and its stream of sparks increased.

"Let go!" cried Andy to those who were holding his craft.

They released their hold. The triplane moved slowly across the ground, gathered speed, and, then, under the impulse of the powerful propellers, ran rapidly over the meadow.

"Hurrah! There he goes!" cried Sam.

"Yes! Now he's going to fly," proudly added Pete Bailey, the other crony of the bully.

"He'd better fly soon, then, or he'll be in the ditch," said Tom grimly, for a little, sluggish stream crossed the meadow not far from where Andy had started.

The next instant, thinking he had momentum enough, Andy tilted his elevation plane. The clumsy triplane rose into the air and shot forward.

"There he goes!" cried Sam.

"Hurrah!" yelled the crowd.

Andy had gone up about ten feet, and was making slow progress.

"I guess Tom Swift isn't the only one in Shopton who can build an airship!" sneered Pete Bailey.

"Look! Look!" yelled Ned. "He's coming down!"

Sure enough, Andy's machine had reached the end of her flight. The motor stopped with something between a cough and a wheeze. Down fluttered the aeroplane, like some clumsy bird, down into the ditch, settling on one side, and then coming to rest, tilted over at a sharp angle. Andy was pitched out, but landed on the soft mud, for there had been a thaw. He wasn't hurt much, evidently, for he soon scrambled to his feet as the crowd surged toward him.

"Well, he flew a little way," observed Ned, grimly.

"But he came down mighty soon," added Tom. "I thought he would. His machine is too big and clumsy. I've seen enough. Come on, Ned. We'll get ready to go to Alaska. Andy Foger will never follow us in that machine."

But Tom was soon to find out how much mistaken he was.

READY FOR THE TRIP

Andy Foger stood looking at his tilted airship. His clothes were covered with mud from the ditch, some of the muck had splashed over his face so that he was a pitiable looking object.

"What's the matter?" panted Pete Bailey.

"Are you hurt?" asked Sam Snedecker.

The two cronies had hurried to the side of the bully.

"Matter? Can't you see what's the matter?" demanded Andy wrathfully. "The machine came down, that's what's the matter! Why didn't you fellows fix the motor better?" he shouted at the two machinists as they came running up, followed by the crowd.

"Fix it better? The motor was all right," declared the taller machinist. "Any of them are likely to stop unexpectedly."

"Well, I didn't think mine would," came from Andy. "Now look at my airship! It's all busted!"

"No, it isn't hurt much," said the other man, after critically looking it over. "We can fix it, and you'll fly yet, Andy."

"I hope I do, if only to fool Tom Swift," declared the bully, as he wiped some of the mud from his face. "Come on, now, help me wheel the machine back, and I'll try it again."

Andy made another attempt, but this time the machine did not even rise off the ground, and then, amid the jeers of the crowd, the discomfited lad took his aeroplane back to the shed in the rear of his house.

"I'll fix it yet, and make a long flight," he declared. "I'll show Tom Swift he can't laugh at me!"

"You'll make a long flight eh?" asked one of the machinists. "Where will you go?"

"Never mind," answered Andy, with a knowing wink. "I've got a plan up my sleeve—my father and I are going to do something that will astonish everybody in Shopton," and then Andy, with many nods and winks, went into the shed, where he began giving orders about the airship. He wanted the motor changed, and one of the machinists made some suggestions about the planes, which, he said, would give better results.

As for Tom and Ned, they strolled away, satisfied that in Andy Foger they would not have a very dangerous rival, as far as airships were concerned.

Tom thought matters over during the next few days. He was now satisfied that Andy had a copy of the map, and, as far as he could see, there was no way of getting it from him, for he could not prove to the satisfaction of the legal authorities that the bully actually had it.

"We'll just have to take a chance, that's all," decided the young inventor in talking matters over with his father, Ned, and Abe Abercrombie. "If Andy and some of his crowd trail after us, we'll just have to run away from them and get to the valley first."

"If they do get there, they won't find it very easy traveling I reckon," remarked Abe. "They'll get all they want of the caves of ice. But hadn't we better get a hustle on ourselves, Tom?"

"Yes, we will soon start now. I have the RED CLOUD all packed up for shipment to Seattle. We will send it on ahead, and then follow, for it will take some time to get there, even though it's going by fast freight."

"What about Mr. Damon?" asked Ned. "When is he coming?"

"There's no telling," responded Tom. "He may be on hand any minute, and, again, he may only show up just as we are starting. I haven't heard from him in the last day or two."

At that moment there was a knock on the private office in the aeroplane shed, where Tom, Ned and Abe Abercrombie were talking.

"Who's there?" asked Tom.

"It's me," answered a voice recognizable as that of the colored man Eradicate.

"What is it, Rad?" asked Tom.

"Why I jest thought I'd tell you dat de blessin' man am comin' down de road."

"The blessing man?" repeated Tom. "Oh, you mean Mr. Damon."

"Yais, sah, dat's jest who I done mean. An' dere's anodder gen'man wif him."

"Mr. Parker, I expect," spoke Tom. "Well, tell them to come in here, Rad."

"Yais, sah. Dey's comin' up de path now, so dey is."

The next moment Tom and the others heard a voice saying:

"Why, bless my necktie! The RED CLOUD is gone!" Mr. Damon had peered into the shed, and had not seen the airship, for Tom had it packed up. "I wonder if Tom Swift has gone away? Bless my top-knot, Mr. Parker, I hope we're not too late!"

"Indeed I hope not," added the scientist. "I wish to make a study of the caves of ice. I think perhaps they may be working south, and, in time, this part of the country may be covered deep under a frozen blanket."

"Cheerful, isn't he, Ned?" asked Tom, with a smile. Then, going to the door of the shed he called out: "Here we are, Mr. Damon. Glad to see you, Mr. Parker." This last wasn't exactly true, but Tom wanted to be polite.

"Bless my collar button, Tom! But what has become of the airship?" asked Mr. Damon, as he looked about the shed, and saw only a number of boxes and crates.

"Taken apart, and packed up, ready for the trip to the valley of gold and the caves of ice," replied the young inventor, and then he briefly told of their plans.

"Well, that's a good idea," declared the eccentric man. "Mr. Parker and I are ready to go whenever you are, Tom."

"Then we'll start very soon. I will get all our supplies in Seattle. Now, to discuss details," and, after Mr. Parker and Mr. Damon had been made acquainted with the old miner, who told his story in brief, they began a discussion of the prospective trip.

Mr. Damon and Mr. Parker took up their residence in Tom's house, and while the eccentric man busied himself in helping our hero, Ned and Abe Abercrombie in getting ready for the trip to Alaska, the gloomy scientist went about making "observations" as he called them, with a view to predicting what might happen in the near future.

He was particularly anxious to get up north, among the caves of ice, and, several times he repeated his statement that he believed the mass of ice in Alaska was working down toward the south. But no one paid much attention to him, though Tom recalled, not without a little shudder, that Mr. Parker had correctly predicted the destruction of Earthquake Island, and also the landslide on Phantom Mountain.

The airship was finally sent off, being forwarded to Seattle in sections, where it could easily be put together. The matter of Andy Foger having a duplicate map of the valley of gold was discussed, but it was agreed that nothing could be done about it. So Tom and the others devoted all their energies to getting in shape for their prospective journey.

Mr. Swift was invited to go, but declined on the ground that he had several inventions to perfect, nor could Mr. Jackson go, as he was needed to help his employer. So Tom, Ned, Mr. Damon, Mr. Parker and Abe Abercrombie made up the party. Tom arranged to send wireless messages to his father from the airship once they were started off toward the valley of gold, and over the frozen north.

One evening, when Tom had been to pay a last visit to Mary Nestor, as he was coming past the Foger premises he saw a number of large vans, loaded with big packing cases coming out of the banker's yard.

"Hum! I wonder if they're moving?" mused our hero. "If they are they're taking a queer time for it." He paused a moment to look at the procession of vans. As he did so he heard the voice of Andy Foger.

"Now, I want you men to be careful of everything!" the bully called out arrogantly. "If you break anything I'll sue you for damages!"

"Oh, that cub makes me sick!" exclaimed one of the drivers as he came opposite Tom.

"What are you moving—eggs, that you have to be so careful?" asked the young inventor, in a low voice.

"Eggs? No! But it might just as well be," was the growling answer. "He's shipping an airship, all taken to pieces, and he has nervous prostration for fear it will be broken. I don't believe the old thing's any good, anyhow."

"An airship—Andy Foger sending away his airship?" gasped Tom. "Where to?"

"Some place in Alaska," was the startling reply. "Pitka or Sitka, or some such place like that. It's all in these boxes, G'lang there!" this to his horses.

"Andy sending his airship to Alaska!" murmured Tom in dismay. "Then he surely is going to make a try for that valley of gold!"

He turned away, while the snarling voice of the bully rang out on the night, urging the drivers to be very careful of the boxes and crates on their trucks.

A THIEF IN THE NIGHT

Tom Swift hardly knew what to think. He had scarcely believed, in spite of the fact that he was sure Andy had a copy of the map, that the bully would actually make an effort to go to the valley of gold.

"And in that airship of his, too," mused Tom. "Well, there's one consolation, I don't believe he'll go far in that, though it does sail better than when he made his first attempt. Well, if he's going to try to beat us, it's a good thing I know it. We can be prepared for him, now."

Tom, after watching the big vans for a few minutes, turned and kept on toward his home.

There was more than surprise on the part of Mr. Damon and the others when Tom told his news. There was alarm, for there was a feeling that Mr. Foger and his son might adopt unscrupulous tricks.

"But what can we do?" asked Mr. Swift.

"Whitewash him!" exclaimed Eradicate Sampson, who had overheard part of the conversation. "Dat's what I'd do t' him an' his father, too! Dat's what I would! Fust I'd let mah mule Boomerang kick him a bit, an' den, when he was all mussed up, I'd whitewash him!" That was the colored man's favorite method of dealing with enemies, but, of course, he could not always carry it out.

However, after considering the matter from all sides, it was decided that nothing could be done for the present.

"Let them go," said Tom, "I don't believe they'll ever find the valley of gold. I fancy I threw a scare into Andy, talking as I did about the map."

"Well, even if the Fogers do get the gold," said Mr. Parker calmly, "they cannot take away the caves of ice, and it is in them that I am most interested. I want to prove some of my new theories."

"And we need the gold," said Tom, in a low voice; "don't we, Abe?"

"That's what we do, Tom," answered the old miner.

Preparations were now practically completed for their trip to Seattle by rail. Tom made some inquiries in the next few days regarding the Fogers, but only learned that the father and son had left town, after superintending the shipment of their airship.

"Well, we start to-day," remarked Tom, as he arose one morning. "In two weeks, at most, we ought to be hovering over the valley, Abe."

"I hope so, Tom. You've got the map put away safely, have you?"

"Sure thing. Are you all ready?"

"Yes."

"Then we'll start for the depot right after breakfast." The adventurers had arranged to take a local train from Shopton, and get on a fast express at one of the more important stations.

Good-byes were said, Mr. Swift, Mr. Jackson, Mrs. Baggert and Eradicate waving their adieus from the porch as Tom and the others started for the depot. Miss Mary Nestor had bidden our hero farewell the previous night—it being a sort of second good-bye, for Tom was a frequent caller at her house, and, if the truth must be told he rather disliked to leave the young lady.

Tom found a few of his friends at the station, who had gathered there to give him and Ned BON-VOYAGE.

"Bring us back some nuggets, Tom," pleaded Arthur Norton.

"Bring me a musk-ox if you can shoot one," suggested one.

"A live bear or a trained Eskimo for mine," exclaimed another.

Tom laughingly promised to do the best he could.

"I'll send you some gold nuggets by wireless," said Ned Newton.

It was almost time for the train to arrive. In the crowd on the platform Tom noticed Pete Bailey.

"He must feel lost without Andy," observed the young inventor to Ned.

"Yes, I wonder what he's hanging around here for?"

They learned a moment later, for they saw Pete going into the telegraph office.

"Must be something important for him to wire about," observed Ned.

Tom did not answer. The window of the office was slightly open, though the day was cool, and he was listening to the clicks of the telegraph instrument, as the operator sent Pete's message. Tom was familiar with the Morse code. What was his surprise to hear the message being sent to Andy Foger at a certain hotel in Chicago. And the message read:

"Tom Swift's party leaving to-day."

"What in the world does that mean?" thought Tom, but he did not tell Ned what he had picked up as it went over the wire. "Why should Andy want to be informed when we leave? That's why Pete was hanging around here! He had been instructed to let Andy know when we left for Seattle. There's something queer back of all this."

Tom was still puzzling over the matter when their train roiled in and he and the others got aboard.

"Well, we're off!" cried Ned.

"Yes; we're off," admitted Tom, and, to himself he added: "No telling what will happen before we get there, though."

The trip to Chicago was without incident, and, on arrival in the Windy City, Tom was on the lookout for Andy or his father, but he did not see them. He made private inquiries at the hotel mentioned in Pete's telegram, but learned that the Fogers had gone on.

"Perhaps I'm worrying too much," thought Tom. But an event that occurred a few nights later, when they were speeding across the continent showed him that there was need of great precaution.

On leaving Chicago, Tom had noticed, among the other passengers traveling in the same coach as themselves, a man who seemed to be closely observing each member of the party of gold-hunters. He was a man with a black mustache, a mustache so black, in fact, that Tom at once concluded that it had been dyed. This, in itself, was not much, but there was a certain air about the man—a "sporty" air—which made Tom suspicious.

"I wouldn't be surprised if that man was a gambler, Ned," he said to his chum, one afternoon, as they were speeding along. The man in question was several seats away from Tom.

"He does look like one," agreed Ned.

"I needn't advise you not to fall in with any of his invitations to play cards, I suppose," went on Tom, after a pause.

"No, indeed, it's something I don't do," answered Ned, with a laugh. "But it might be a good thing to speak to Abe Abercrombie about him. If that man's a sharper perhaps Abe knows him, or has seen him, for Abe has traveled around in the West considerable."

"We'll ask him," agreed Tom, but the miner, when his attention was called to the man, said he had never seen him before.

"He does look like a confidence man," agreed Abe, "but as long as he doesn't approach us we can't do anything, and don't need to worry."

There was little need to call the attention of either Mr. Damon or Mr. Parker to the man, for Mr. Damon was busy watching the scenery, as this trip was a new one to him, and he was continually blessing something he saw or thought of. As for Mr. Parker, he was puzzling over some new theories he had in mind, and he said little to the others.

On the night of the same day on which Tom had called special attention to the man with the black mustache, our hero went to his berth rather late. He had sent some telegrams to his father and one to Miss Nestor, and, when he turned in he saw the "gambler," as he had come to call him, going into the smoking compartment of the coach. Though Tom thought of the man as a gambler, there was no evidence, as yet, that he was one, and he had made no effort to approach any of our friends, though he had observed them closely.

How long Tom had been asleep he did not know, but he was suddenly awakened by feeling his pillow move. At first he thought it was caused by the swaying of the train, and he was about to go to sleep again, when there came a movement that he knew could not have been caused by any unevenness of the roadbed.

Then, like a flash there came to Tom's mind the thought that under his pillow, in a little leather case he had made for it, was the map, showing the location of the valley of gold.

He sat up suddenly, and made a lunge for the pillow. He felt a hand being hurriedly withdrawn. Tom made a grab for it, but the fingers slipped from his grasp.

"Here! Who are you!" cried Tom, endeavoring to peer through the darkness.

"It's all right—mistake," murmured a voice.

Tom leaned suddenly forward and parted the curtains of his berth. There was a dim light burning in the aisle of the car. By the gleam of it the young inventor caught sight of a man hurrying away, and he felt sure the fellow who had put his hand under his pillow was the man with the black mustache. He confirmed this suspicion a moment later, for the man half turned, as if to look back, and the youth saw the mustache.

"He—he was after my map!" thought Tom, with a gasp.

He sat bolt upright. What should he do? To raise an alarm now, he felt, would only bring a denial from the man if he accused him. There might also be a scene, and the man might get very indignant. Then, too, Tom and his friends did not want their object made known, as it would be in the event of Tom raising an outcry and stating what was under his pillow.

He felt for the map case, opened it and saw, in the gleam of the light, that it was safe.

"He didn't get it anyhow," murmured our hero. "I guess I won't say anything until morning, though he did come like a thief in the night to see if he could steal it."

Tom glanced to where his coat and other clothing hung in the little berth-hammock, and a hasty search showed that his money and ticket were safe.

"It was the map he was after all right," mused Tom. "I'll have a talk with Mr. Damon in the morning about what's best to do. That's why the fellow has been keeping such a close watch on us. He wanted to see who had the map."

Then another thought came to Tom.

"If it was the map he was after," he whispered to himself, "he must know what it's about. Therefore the Fogers must have told him. I'll wager Andy or his father put this man up to steal the map. Andy's afraid he hasn't got a copy of the right one. This is getting more and more mysterious! We must be on our guard all the while. Well, I'll see what I'll do in the morning."

But in the morning the man with the black mustache was not aboard the train, and on inquiring of the conductor, Tom learned that the mysterious stranger had gotten off at a way station shortly after midnight.

A VANDAL'S ACT

"Bless my penknife!" exclaimed Mr. Daman, the next morning, when he had been told of Tom's experience in the night, "things are coming to a pretty pass when our enemies adopt such tactics as this! What can we do, Tom? Hadn't you better let one of us carry the map?"

"Oh, I guess not," answered the young inventor. "They have had one try at me, and found that I wasn't napping. I don't believe they'll try again. No, I'll carry the map."

Tom concealed it in an old wallet, as he thought it was less likely to attract attention there than in the new case he formerly used. Still he did not relax his vigilance, and his sleep for the next few nights was uneasy, as he awakened several times, thinking he felt a hand under his pillow.

At length Ned suggested that one of them sit up part of the night, and keep an eye on Tom's berth. This was agreed to, and they divided the hours of darkness into watches, each one taking a turn at guarding the precious map. But they might have spared themselves the trouble, for no further attempt was made to get it.

"I'd just like to know what Andy Foger's plans are?" said Tom one afternoon, as they were within a few miles of Seattle. "He certainly must have made up his mind quickly, after he saw the map, about going in search of the gold."

"Maybe his father proposed it," suggested Ned. "I heard, in our bank, that Mr. Foger has lost considerable money lately, and he may need more."

"I shouldn't wonder. Well, if they are going to Sitka, Alaska, to assemble their ship, I think they'll have trouble, for supplies are harder to get there than in Seattle. But we'll soon be on our way ourselves, if nothing happens. I hope all the parts of the RED CLOUD arrive safely."

They did, as Tom learned a few hours later, when they had taken up their quarters in a Seattle hotel, and he had made inquiries at the railroad office. In the freight depot were all the boxes and crates containing the parts of the big airship, and by comparison with a list he had made, the young inventor found that not a single part was missing.

"We'll soon have her together again," he said to his friends, "and then we'll start for Alaska."

"Where are you going to assemble the airship?" asked Mr. Damon.

"I've got to hire some sort of a big shed," explained Tom. "I heard of one I think I can get. It's out at the fair grounds, and was used some time ago when they had a balloon ascension here. It will be just what I need."

"How long before we can start for the gold valley?" asked the old miner anxiously.

"Oh, in about a week," answered the lad, "that is, if everything goes well."

Tom lost no time in getting to work. He had the different parts of his airship carted to the big shed which he hired. This building was on one edge of the fair grounds, and there was a large, level space which was admirably adapted for trying the big craft, when once more it was put together.

The gold-seekers worked hard, and to such good purpose that in three days most of the ship was together once more, and the RED CLOUD looked like herself again. Tom hired a couple of machinists to aid him in assembling the motor, and some of the gas appliances and other apparatus.

"Ha! Bless my rubber shoes!" cried Mr. Damon in delight, as he looked at the big craft "This is like old times, Tom!"

"Yes, indeed," agreed our hero.

"Are you going to give it a preliminary tryout?" asked Ned.

"Oh, yes, I think we can do that to-morrow," replied Tom. "I want to know that everything is in good working shape before I trust the ship on the trip to the frozen north. There are several problems I want to work out, too, for I think I will need a different kind of gas up where the temperature is so low."

"It certainly is cold up here," agreed Ned, for they were now much farther north than when they were in Shopton, and, besides, winter was coming on. It was not the best time of the year to journey into Alaska, but they had no choice. To delay, especially now, might mean that their enemies would get ahead of them.

"We'll be warm in the airship, though; won't we?" asked Abe.

"Oh, yes," answered Tom. "We'll be warm, and have plenty to eat. Which reminds me that I must begin to see about our stock of provisions and other supplies, for we'll soon be on our way."

Work on the airship was hastened to such good advantage the next two days that it was in shape for a trial flight, and, one afternoon, the RED CLOUD was wheeled from the shed out into big field, the gas was generated, and the motor started.

There was a little hitch, due to the fact that some of the machine adjustments were wrong, but Tom soon had that remedied and then, with the big propellers whirling around, the airship was sent scudding across the field.

Another moment and it rose like a great eagle, and sailed through the air, while a small crowd that had daily gathered in the hope of seeing a flight, sent up a cheer.

"Does it work all right?" asked Ned anxiously, as he stood in the pilothouse beside his chum.

"As good as it did in Shopton," answered the young inventor, proudly.

"Bless my pocketbook! but that's lucky," exclaimed Mr. Damon. "Then we can soon start, eh?"

"As soon as we are stocked up," replied the lad.

Tom put the airship through a number of "stunts" to test her stability and the rudder control, much to the delight of the gathering throng. Everything was found to work well, and after ascending to a considerable height, to the no small alarm of the old miner, Tom made a quick descent, with the motor shut off. The RED CLOUD conducted herself perfectly, and there was nothing else to be desired.

She was sent down to earth and wheeled back into the shed, and not without some difficulty, for the crowd, which was now very large, wanted to get near enough to touch the wonderful craft.

"To-morrow I'll arrange about the supplies and provisions, and we'll stock her up," said Tom to his companions. "Now you folks had better go back to the hotel."

"Aren't you coming?" asked Ned.

I'm going to bunk here in the shed to-night, said the young inventor.

"What for?"

"I can't take any chances now that the RED CLOUD is in shape for flying. Some of the Foger crowd might be hanging around, and break in here to damage her."

"But the watchman will be on guard," suggested Ned, for since the hiring of the shed, the young inventor had engaged a man to remain on duty all night.

"I know," answered Tom Swift, "but I'm not going to take any chances. I'll stay here with the watchman."

Ned offered to share the vigil with his chum, and, after some objection Tom consented. The others went back to the hotel, promising to return early in the morning.

Tom slept heavily that night, much heavier than he was in the habit of doing. So did Ned, and their deep breathing as they lay in their staterooms, in the cabin of the airship, told of physical weariness, for they had worked hard to re-assemble the RED CLOUD.

The watchman was seated in a chair just inside the big door of the shed, near a small stove in which was a fire to take off the chill of the big place. The guard had slept all day, and there was no excuse for him nodding in the way that he did.

"Queer, how drowsy I feel," he murmured several times. "It's only a little after midnight, too," he added, looking at his watch, "Guess I'll walk around a bit to rouse myself."

He firmly intended to do this, but he thought he would wait just a few minutes more, and he stretched out his legs and got comfortable in the chair.

Three minutes more and the watchman was asleep—sound asleep, while a strange, sweet, sickish odor seemed to fill the atmosphere about him.

There was a noise at the door of the shed, a door in which there were several cracks. A man outside laid aside something that looked like an air pump. He applied one eye to a crack, and looked in on the sleeping watchman.

"He's off," the man murmured. "I thought he'd never get to sleep! Now to get in and dose those two lads! Then I'll have the place to myself!"

There was a clicking noise about the lock on the shed door. It was not a very secure lock at best, and, under the skilful fingers of the midnight visitor, it quickly gave way. The man entered. He gave one look at the slumbering watchman, listened to his heavy breathing, and then went softly toward the airship, which looked to be immense in the comparatively small shed—taking up nearly all the space.

The intruder peered in through the cabin windows where Ned and Tom were asleep. Once more there was in the atmosphere a sickish odor. The man again worked the instrument which was like a small air pump, taking care not to get his own face too near it. Presently he stopped and listened.

"They're doped," he murmured. He arose, and took from his mouth and nose a handkerchief saturated with some chemical that had rendered him immune to the effects of the sleep-producing that he had generated. "Sound asleep," he added. Then, taking out a long, keen knife, the vandal stole toward where the great wings of the RED CLOUD stretched out in the dim light like the pinions of a bird. There was a ripping, tearing, rending sound, as the vandal cut and slashed, but Tom, Ned and the watchman slumbered on.

TOM IS HELD UP

Tom Swift stirred uneasily in his heavy sleep. He dreamed that he was again in his berth in the railroad car, and that the thief was feeling under his pillow for the map. Only, this time, there seemed to be hands feeling about his clothing, trying to locate his inner pockets.

The lad murmured something unintelligible, but he did not awaken. The fumes prevented that. However, his movements showed that the effect of the drug was wearing off. It was intended only for temporary use, and it lasted less time than it would otherwise have done in a warmer, moister climate, for the cold, crisp air that penetrated the shed from outside dispelled the fumes.

"Guess I'd better not chance it," murmured the intruder. "He may not have it on him, and if I go through all his pockets I'll wake him up. Anyhow, I've done what they paid me for. I don't believe they'll sail in this airship."

The vandal gave one glance at the sleeping lads, and stole from the cabin of the craft. He looked at his work of ruin, and then tiptoed past the slumbering watchman. A moment later and he was outside the shed, hurrying away through the night.

Several hours after this Mr. Damon and the old miner were pounding on the door of the shed. Mr. Parker, the scientist, had remained at the hotel, for he said he wanted to work out a few calculations regarding some of his theories.

"I thought we'd find them up by this time," spoke the eccentric man, as he again knocked on the door. "Tom said he had lots to do to-day."

"Maybe they are working inside, and can't hear our knocks," suggested Abe. "Try th' door."

"Bless my heart! I never thought of that," exclaimed Mr. Damon. "I believe I will."

The door swung open as he pushed it, for it had not been locked when the intruder left. The first thing Mr. Damon saw was the watchman, still asleep in his chair.

"Bless my soul!" the old man shouted. "Look at this, Abe!"

"Something's wrong!" cried the miner, sniffing the air. "There's been crooked work here! Where are the boys?"

Mr. Damon was close to the airship. He looked in the cabin window.

"Here they are, and they're both asleep, too!" he called. "And—bless my eyeglasses! Look at the airship! The planes and wings are all cut and slashed! Something has happened! The RED CLOUD is all but ruined!"

Abe hastened to his side. He looked at the damage done, and a fierce look came over his face.

"The Fogers again!" he murmured. "We'll pay 'em back for this! But first we must see to the boys!"

They needed small attention, however. The opening of the big door had let in a flood of fresh air, and this dispelled the last of the fumes. The watchman was the first to revive. The sleep caused by the chemical, sprayed from the air-pump by the vandal, had been succeeded by a natural slumber, and this was the case with Ned and Tom. They were soon aroused, and looked with wonder, not unmixed with rage, at the work done in the night.

Every one of the principal planes of the airship, each of the rudders, and some of the auxiliary wings had been cut by a sharp knife—some in several places. The canvas hung in shreds and patches, and the trim RED CLOUD looked like some old tramp airship now. Tom could scarcely repress a groan.

"Who did it?" he gasped.

"And with us here on guard!" added Ned.

"I—I must have fallen asleep," admitted the watchman in confusion.

"You were all asleep," said Mr. Damon. "I couldn't rouse you!"

"And there was th' smell of chloroform, or something like it in th' shed," added the miner.

"But look at the airship!" groaned Tom.

"Is it ruined—can't we go to the valley of gold?" asked Ned.

Tom did not answer for a few minutes. He was walking around looking at his damaged craft. The sleepy feeling was rapidly leaving him, as well as Ned and the watchman.

"Bless my watch chain!" exclaimed Mr. Damon. "What an ugly, mean piece of work. Can you repair it, Tom?"

"I think so," was the hesitating answer. "It is not as bad as I feared at first. Luckily the gas-bag has not been touched, for, if it had, we could hardly have repaired it. I can fix the wings and the rudders. The propellers have not been damaged, nor has the motor been touched. I think they must have made another attempt to take the map off me," he went on, as he looked at several pockets that had been turned inside out.

An examination of the door showed how the lock had been forced, and the adventurers could easily guess the rest. But who the midnight vandal was they could not tell, though Tom and the others were sure it was some one hired by the Fogers.

"They wanted to delay us," said Tom. "They thought this would hold us back, but it won't—for long. We'll get right to work, and make new planes and rudders. Fortunately the framework isn't hurt any."

Once Tom got into action nothing held him back. He hardly wanted to stop for meals. New canvas was ordered, and that very afternoon some of the damaged wings had been repaired. In the meanwhile the stores and provisions that had been ordered were arriving, and, under the direction of the miner and Mr. Damon were put in the RED CLOUD. Tom and Ned, with the help of a man they hired, worked diligently to replace the damaged planes and rudders. Mr. Parker came out to the airship shed, but he was of little use as a helper, for he was continually stopping to jot down some memoranda about an observation he thought of, or else he would lay aside his tools to go outside, look at the weather, and make predictions.

But Tom and the others labored to such good advantage that in three days they had repaired most of the damage done. Luckily the vandal had cut and slashed in a hurry, and his malicious work was only half accomplished. There was no clue to his identity.

No trace was seen of the Fogers, and Tom hardly expected it, for he thought they were in Sitka by this time. Nor were any suspicious persons seen hanging around the shed. The adventurers left their rooms at the hotel, and took up their quarters in the airship that would soon be their home for many days. They wanted to be where they could watch the craft, and two guards were engaged.

"We'll start to-morrow," Tom announced gaily one evening when, after a hard day's work the last of the damaged planes had been repaired.

"Start fer th' valley of gold?" asked the miner.

"Yes. Everything is in good shape now. I want to go into town, to send some messages home, telling dad we'll soon be on our way, and I also want to get a few things."

"Shall I come?" asked Ned.

"No, I'd rather you'd stay here," spoke Tom, in a low voice. "We can't take any more chances of being delayed, and, as it's pretty well known that we'll sail to-morrow, the Foger crowd may try some more of their tricks. No, I'll go to town alone, Ned. I'll soon be back, however. You stay here."

But Tom came nearly never coming back. As he was returning from sending the messages, and purchasing a few things he needed for the trip, he passed through a dark street. He was walking along, thinking of what the future might hold for him and his companions, after they reached the caves of ice, when, just as he got to a high board fence, surrounding some vacant lots, he heard some one whisper hoarsely:

"Here he comes!"

The young inventor was on his guard instantly. He jumped back to avoid a moving shadow, but was too late. Something struck him on the back of his head, and he felt his senses leaving him. He struggled against the feeling, and he realized, even in that exciting moment, that the thick collar of his heavy overcoat, which he had turned up because of a cold wind, had, perhaps, saved him from a broken skull.

"Hold him!" commanded another voice. "I'll go through him!"

The packages dropped from Tom's nerveless fingers. He felt himself sinking down, in spite of his fierce determination not to succumb. He felt several hands moving rapidly about his body, and then he struck blindly out at the footpads.

OFF FOR THE FROZEN NORTH

Tom Swift felt as if he was struggling in some dream or nightmare. He felt strong hands holding him and saw evil faces leering at him.

Then gradually his brain cleared. His muscles, that had been weakened by the cowardly blow, grew strong. He felt his fist land heavily on some one's face. He heard a smothered gasp of pain.

Then came the sound of footsteps running—Tom heard the "ping" of a policeman's night-stick on the sidewalk.

"Here come the cops!" he heard one voice exclaim.

"Did you get it?" asked another.

"No, I can't find it. Cut for it now!"

They released the young inventor so suddenly that he staggered about and almost fell.

The next moment Tom was looking into the face of a big policeman, who was half supporting him.

"What's the matter?" asked the officer.

"Hold-up, I guess," mumbled the lad. "There they go!" he pointed toward two dark forms slipping along down the dimly-lighted street.

The officer drew his revolver, and fired two shots in the air, but the fleeing figures did not stop.

"How did it happen?" asked the policeman. "Did they get anything from you?"

"No—I guess not," answered Tom. He saw the packages containing his purchases lying where they had fallen. A touch told him his watch and pocketbook were safe. The precious map was in a belt about his waist, and that had not been removed. "No, they didn't get anything," he assured the officer.

"I came along too quick for 'em, I guess," spoke the bluecoat. "This is a bad neighborhood. There have been several hold-ups here of late, but I was on the job too soon for these fellows. Hello, Mike," as another officer came running up in answer to the shots and the raps of the night-stick. "Couple of strong-arm-men tackled this young fellow just now. I saw something going on as I turned the corner, and I rapped and ran up. They went down that way. I fired at 'em. You take after 'em, Mike, and I'll stay here. Don't believe you can land 'em, but try! I came up too quick to allow 'em to get anything, though."

Tom did not contradict this. He knew, however, that, had the men who attacked him wished to take his watch or money, they could have done it several times before the officer arrived.

"It was the map they were after," thought Tom, "not my watch or money. This is more of the Foger's work. We must get away from here."

The policeman inquired for more particulars from Tom, who related how the hold-up had taken place. The young inventor, however, said nothing about the map he carried, letting the officer think it was an ordinary attempt at robbery, for Tom did not want any reference in the newspapers to his search for the valley of gold.

Presently the other policeman returned, having been unable to get any trace of the daring men. The two bluecoats wanted to accompany Tom back to the airship shed, for his own safety, but he declared there was no more danger, and, after having given his name, so that the affair might be reported at headquarters, he was allowed to go on his way. His head ached from the blow, but otherwise he was unhurt.

"Those fellows have been keeping watch for me," the lad reasoned, as he walked quickly toward the airship shed. "They must have been shadowing me, and they hid there until I came back. Andy Foger and his father must be getting desperate. I think I know why, too. That little dig I gave Andy about his map is bearing fruit. He begins to think it's the wrong map, and he wants to get hold of the right one. Well, they shan't if I can help it. We'll be away from here in the morning."

There was indignation and some alarm among Tom's friends when he told his story a little later that night.

"Bless my walking-stick!" cried Mr. Damon. "You'll need a bodyguard after this."

"I'd just like t' git my hands on them fellers!" exclaimed the old miner. "I'd show 'em!" and a look at his rugged frame and his muscular arms and gnarled hands showed Tom and Ned that in the event of a fight they could count much on Abe Abercrombie.

"I am glad there will be no more delays, and that we will soon be moving northward," spoke Mr. Parker, a little later. "I am anxious to confirm my theory about the advance of the ice crust, I met a man to-day who had just returned from the north of Alaska. He said that a severe winter had already set in up there. So I am anxious to get to the ice caves."

"So am I," added Tom, but it was for a different reason.

They were all up early the next morning, for there were several things to look after before they started on the trip that might bring much of danger to the adventurers. Under Tom's direction, more gas was generated, and forced into the big bag. A last adjustment was made of the planes, wing tips and rudders, and the motor was given a try-out.

"I guess everything is all right," announced the young inventor. "We'll take her out."

The RED CLOUD was wheeled from the big shed, and placed on the open lot, where she would have room to rush across the ground to acquire momentum enough to rise in the air. Tom, whenever it was practical, always mounted this way, rather than by means of the lifting gas, as, in the event of a wind, he would have better control of the ship, while it was ascending into the upper currents of air, than when it was rising like a balloon.

"All aboard!" cried the lad, as he looked to see that the course was clear. Early as it was, there was quite a crowd on hand to witness the flight, as there had been every day of late, for the population of Seattle was curious regarding the big craft of the air.

"Let her go!" cried Ned Newton, enthusiastically.

Tom took his place in the steering-tower, or pilothouse, which was forward of the main cabin. Ned was in the engine-room, ready to give any assistance if needed. Mr. Damon, Mr. Parker and Abe Abercrombie were in the main cabin, looking out of the windows at the rapidly increasing throng.

"Here we go!" cried the young inventor, as he pulled the lever starting the motor, There was a buzz and a hum. The powerful propellers whirred around like blurs of light. Forward shot the great airship over the ground, gathering speed at every revolution of the blades.

Tom tilted the forward rudder to lift the ship. Suddenly it shot over the heads of the crowd. There was a cheer and some applause.

"Off for the frozen north!" cried Ned, waving his cap.

Tom shifted the rudder, to change the course of the airship. Mr. Damon was gazing on the crowd below.

"Tom! Tom!" he cried suddenly. "There's the man with the black mustache—the man who tried to rob you in the sleeping-car!" He pointed downward to some one in the throng.

"He can't get us now!" exclaimed Tom, as he increased the speed of the RED CLOUD, and then, taking up a telescope, after setting the automatic steering gear, Tom pointed the glass at the person whom Mr. Damon had indicated.

PELTED BY HAILSTONES

"Yes, that's the man all right," observed the lad. "But if he came here to have another try for the map, he's too late. I hope we don't land now until we are in the valley of gold." Tom passed the telescope to Ned, who confirmed the identification.

"Perhaps he came to see if we started, and then he'll report to Andy Foger or his father by telegraph," suggested Mr. Damon.

"Perhaps," admitted Tom. "Anyhow, we're well rid of our enemies—at least for a time. They can't follow us up in the air." He turned another lever and the RED CLOUD shot forward at increased speed.

"Maybe Andy will race us," suggested Ned.

"I'm not afraid of anything his airship can do," declared Tom. "I don't believe it will even get up off the ground, though he did make a short flight before he packed up to follow us. It's a wonder he wouldn't think of something himself, instead of trying to pattern after some one else. He tried to beat me in building a speeding automobile, and now he wants to get ahead of me in an airship. Well, let him try. I'll beat him out, just as I've done before."

They were now over the outskirts of Seattle, flying along about a thousand feet high, and they could dimly make out curious crowds gazing up at them. The throng that had been around the airship shed had disappeared from view behind a little hill, and, of course, the man with the black mustache was no longer visible, but Tom felt as if his sinister eyes were still gazing upward, seeking to discern the occupants of the airship.

"We're well on our way now," observed Ned, after a while, during which interval he and Tom had inspected the machinery, and found it working satisfactorily.

"Yes, and the RED CLOUD is doing better than she ever did before," said Tom. "I think it did her good to take her apart and put her together again. It sort of freshened her up. This machine is my special pride. I hope nothing happens to her on this journey to the caves of ice."

"If my theory is borne out, we will have to be careful not to get caught in the crush of ice, as it makes its way toward the south," spoke Mr. Parker with an air as if he almost wished such a thing to happen, that he might be vindicated.

"Oh, we'll take good care that the RED CLOUD isn't nipped between two bergs," Tom declared.

But he little knew of the dire fate that was to overtake the RED CLOUD, and how close a call they were to have for their very lives.

"No matter what care you exercise, you cannot overcome the awful power of the grinding ice," declared the gloomy scientist. "I predict that we will see most wonderful and terrifying sights."

"Bless my hatband!" cried Mr. Damon, "don't say such dreadful things, Parker my dear man! Be more cheerful; can't you?"

"Science cannot be cheerful when foretelling events of a dire nature," was the response. "I would not do my duty if I did not hold to my theories."

"Well, just hold to them a little more closely," suggested Mr. Damon. "Don't tell them to us so often, and have them get on our nerves, Parker, my dear man. Bless my nail-file! be more cheerful. And that reminds me, when are we going to have dinner, Tom?"

"Whenever you want it, Mr. Damon. Are you going to act as cook again?"

"I think I will, and I'll just go to the galley now, and see about getting a meal. It will take my mind off the dreadful things Mr. Parker says."

But if the gloomy scientific man heard this little "dig" he did not respond to it. He was busy jotting down figures on a piece of paper, multiplying and dividing them to get at some result in a complicated problem he was working on, regarding the power of an iceberg in proportion to its size, to exert a lateral pressure when sliding down a grade of fifteen per cent.

Mr. Damon got an early dinner, as they had breakfasted almost at dawn that morning, in order to get a good start. The meal was much enjoyed, and to Abe Abercrombie was quite a novelty, for he had never before partaken of food so high up in the air, the barograph of the RED CLOUD showing an elevation of a little over twelve thousand feet.

"It's certainly great," the old miner observed, as he looked down toward the earth below them, stretched out like some great relief map. "It sure is wonderful an' some scrumptious! I never thought I'd be ridin' one of these critters. But they're th' only thing t' git t' this hidden valley with. We might prospect around for a year, and be driven back by the Indians and Eskimos a dozen times. But with this we can go over their heads, and get all the gold we want."

"Is there enough to give every one all he wants?" asked Tom, with a quizzical smile. "I don't know that I ever had enough."

"Me either," added Ned Newton.

"Oh, there's lots of gold there," declared the old miner. "The thing to do is to get it and we can sure do that now."

The remainder of the day passed uneventfully, though Tom cast anxious looks at the weather as night set in, and Ned, noting his chum's uneasiness, asked:

"Worrying about anything, Tom?"

"Yes, I am," was the reply. "I think we're in for a hard storm, and I don't know just how the airship will behave up in these northern regions. It's getting much colder, and the gas in the bag is condensing more than I thought it would. I will have to increase our speed to keep us moving along at this elevation."

The motor was adjusted to give more power, and, having set it so that it, as well as the rudders, would be controlled automatically, Tom rejoined his companions in the main cabin, where, as night settled down, they gathered to eat the evening meal.

Through the night the great airship plowed her way. At times Tom arose to look at some of the recording instruments. It was growing colder, and this further reduced the volume of the gas, but as the speed of the ship was sufficient to send her along, sustained by the planes and wings alone, if necessary, the young inventor did not worry much.

Morning broke gray and cheerless. A few flakes of snow fell. There was every indication of a heavy storm. They were high above a desolate and wild country now, hovering over a sparsely settled region where they could see great forests, stretches of snow-covered rocks, and towering mountain crags.

The snow, which had been lazily falling, suddenly ceased. Tom looked out in surprise. A moment later there came a sound as if some giant fingers were beating a tattoo on the roof of the main cabin.

"What's that!" cried Ned.

"Bless my umbrella! has anything happened?" demanded Mr. Damon.

"It's a hail storm!" exclaimed Tom. "We've run into a big hail storm. Look at those frozen stones! They're as big as hens' eggs!"

On a little platform in front of the steering-house could be seen falling immense hailstones. They played a tattoo on the wooden planks.

"A hail storm! Bless my overshoes!" cried Mr. Damon.

"A hail storm!" echoed Mr. Parker. "I expected we would have one. The hailstones will become even larger than this!"

"Cheerful," remarked Tom in a low voice, with an apprehensive look at Ned.

"Is there any danger?" asked his chum.

"Danger? Plenty of it," replied the young inventor. "The frozen particles may rip open the gas bag." He stopped suddenly and looked at a gage on the wall of the steering-tower—a gage that showed the gas pressure.

"One compartment of the bag has been ripped open!" cried Tom. "The vapor is escaping! The whole bag may soon be torn apart!"

The noise of the pelting hailstones increased. The roar of the storm, the bombardment of the icy globules, and the moaning of the wind struck terror to the hearts of the gold-seekers.

"What's to be done?" yelled Ned.

"We must go up, to get above the storm, or else descend and find some shelter!" answered Tom. "I'll first see if I can send the ship up above the clouds!"

He increased the speed of the motor so that the propellers would aid in taking the ship higher up, while the gas-generating machine was set in operation to pour the lifting vapor into the big bag.