CHAPTER I. READY FOR THE TEST.
“Shake, Tom, old boy; ‘tip us your flipper,’ as Captain Andrews would say. The Wondership is ready for her final try-out.”

“Finished.” Tom Jesson drew a long sigh, then he wrung his cousin’s hand with energy enough to have wrenched it loose.

Jack Chadwick flung down the “alligator” wrench with which he had been going over every nut and bolt, and capered about the lofty, bare-raftered shed. Tom’s round face beamed, mirroring the other’s high good humor.

“And the try-out’s going to be a big success, Jack,” he declared positively. “I can feel it in my bones,—like Jupe when his rheumatics are coming on. My! Jack, that pontoon idea was the biggest thing we’ve ever struck.”

“Wait till we’ve tried it out,” smiled Jack, less impetuously; “it may prove the biggest bump we’ve ever struck.”

“Well, I’m willing to risk it. When shall we make the trial trip?”

“No time like the present. There are a few finishing touches still to be seen to, but by this evening everything will be ready. Besides, night is the best time. We don’t want a crowd around. There has been enough curiosity in what we have been doing, already.”

“I should say so. Look at this Boston sheet, will you? A column of mystery for a cent!”

Tom drew from his pocket a copy of a Boston paper and indicated some staring head-lines.

“’A Mystery of The Night Skies!’” he declaimed vociferously, waving an arm. “Some class there, eh?”

“Quite enough,” chuckled Jack. “We didn’t think that our little spin the other night was going to cause such a stir-up, did we?”

“It was all the fault of those red and green lights you hung out,” protested Tom. “Can you blame a community for getting worked up at the spectacle of colored lights like those on a ship, skimming around above their heads at sixty miles an hour? Hullo!” he broke off, still scanning the paper. “Here’s a letter from one fellow who declares that what was seen was a comet.”

“A comet, eh? Well, that wouldn’t be such a bad name for the new Flying Road Racer,” mused Jack reflectively.

“Never heard of a comet that would swim,” retorted Tom.

“Well, we don’t know yet that the new Road Racer will perform the stunts we expect her to.”

“In which case, we are in for a cold, cold bath.”

“Cheer up, Tom,” laughed Jack. “Get busy now and finish up the pontoons with that aluminum paint. If the trial is set for this evening, we haven’t any too much time.”

Both boys fell to work again with feverish energy. The work of many weeks, carried on sometimes in high hope, sometimes in deep despondency, was before them in complete form, except for the final touches. Only the important experiment remained. Would the re-modelled Flying Road Racer do what the boys expected of her? If the answer to that question was in the affirmative, they knew that they had invented and carried to perfection the greatest craft of its kind hitherto known. The new craft would indeed merit her name of Wondership if she did what the boys confidently expected of her.

And what was this Wondership that had for weeks occupied every minute of the Boy Inventors’ time, exclusive of their studies in the Technical College that both attended in Boston? Readers of former volumes of this series will recall the Flying Road Racer, the air and land ship that had carried the boys and their friends faithfully so many miles, and in which they had encountered many stirring adventures. Well, the Wondership, as Jack in his enthusiasm had termed the craft, was nothing more nor less than the Flying Road Racer, altered almost beyond recognition.

The shed in which the changes had been carried out was located on a lonesome part of the seacoast not far from Nestorville, where the boys lived. But, remote as the spot was, it still was not far enough removed from human haunts to escape much speculation over what was going forward in the great, gaunt, unpainted shed among the sand-hills.

Inquisitive folks had watched wagons, laden with big crates and seemingly heavy boxes, making their way to the place at intervals; but so carefully had the shed been guarded and locked that nobody had as yet discovered the boys’ secret. Had anyone done so, it is certain that the two lads would have been besieged by curiosity seekers, for the craft on which they were working was the most ambitious thing that they had undertaken. The Wondership was nothing more nor less than an invention capable of travel by land, air and water. On land it rolled along on wheels, above the earth it depended on a large, gas-filled bag for buoyancy, while on the water (and this was the feature still untested), the boys hoped to make it float like a boat by means of pontoons.

Of course, the idea of pontoons as applied to aerial craft was by no means a novelty. Glen Curtiss, pioneer in this field, already had a fleet of successful hydro-aeroplanes, and many other inventors were laboring along these lines. It was in the application of the idea that the boys had radically departed from anything hitherto known. At the risk of being tedious we must now describe the Wondership at some length, in order that what is to follow of her marvelous adventures may be clear.

Readers of former books relating the experience of the Boy Inventors know that the Flying Road Racer was a craft built like an immense automobile with a semi-cylindrical body. It seated six persons, and at a pinch could accommodate more. The lower part of the cylinder was a big tank in which gas was generated from a concentrated powder which, upon being mixed with water, formed a vapor of extraordinary buoyancy. In the upper part were padded seats, storage chambers for food and supplies, and a machinery chamber housed under a hood.

Above this auto-like structure rose a framework of vanadium and aluminum alloy, on which was folded, when not in use, the gas-bag which lifted the Flying Road Racer from the earth when it was desired to fly. Pumps filled the bag with gas, or withdrew it, as was desired. Provision allowing for the expansion and contraction of the bag had also been made, as was fully described in another volume.

What the boys had done was this: They had extended the semi-cylindrical formation till they had formed a full cylinder of light but strong metal. Roughly, the Flying Road Racer now resembled a huge, gleaming white cigar on wheels. Along her sides stretched hollow aluminum planes, or wings.

In the air these took the place of the former planes used in ascending or descending. On the water it was hoped that they would act as hydroplanes, buoying up the craft. But for buoyancy they did not depend on these hydroplanes, or pontoons, alone. The body of the Flying Road Racer was, by a singular stroke of inventive ingenuity, made to be in itself a buoyant craft.

When running along the road, or while flying, the top of the cylindrical body could be opened for air and observation. On a calm sea or lake the boys believed also that the craft, with the aid of the hydroplanes, would float, just like a boat. The hydroplanes at the side would, of course, correct a tendency to roll over, which an unsupported cylindrical body would naturally have. But in case of rough water, during which they might, in the course of the long flights they meant to take, be compelled to descend, the waves would be apt to break over the craft and swamp it.

To provide against such an emergency the ingenuity of the boys had been called into full play. It took many sleepless nights and days of anxious thought to solve the problem. But they believed that they had found a solution. The open space on the top of the cylinder was provided with metal doors which could be closed and screwed down, forming a water-tight compartment. Thus, the Flying Road Racer would, in a rough sea, be a water-tight cylinder, practically unsinkable unless the light metal hull was punctured.

The next problem had been a difficult one likewise. The question of how to ventilate an air-tight and water-tight cylinder was a vexing one. It was Jack who hit upon a plan. Like most big ideas it was simple, and was suggested to him by a recollection of the periscope tube on the submarine Peacemaker, which, as told in “The Boy Inventors and the Diving Torpedo Boat,” they had helped to construct. Jack’s solution, then, was this: A collapsible twin tube was made which when extended fully would reach upward, above the air-tight cylinder, to a height of twenty-five feet. At the bottom of this tube, and inside the cylinder, was a chamber containing two tiny fans. One of these fans, driven by storage batteries, sucked in fresh air from the top of the tube; the other drew out the foul fumes and sent them up the other channel of the extension pipe.

The Wondership was driven in the air and on land and water by the same power, the gas from the storage chamber which formed the lower section of the cylinder. But to fit her for her new work extra powerful engines had been installed, and a propeller of different pattern added. The propeller-shaft was connected to the motor through a water-tight stuffing box, as on a motor boat. The rudder lines, too, led through water-tight connections to the steering wheel. The aerial rudder, being of light metal like the propeller, was capable of use both in the air and water. In place of the old driving mechanism, too, the boys had simplified the Flying Road Racer by their new form of propeller. This did away with the cumbrous connections and clutches to the rear axle. The new form of propeller drew the Wondership along the roads almost as swiftly as it pulled her through the air.

As for the boys themselves, as readers of earlier volumes of this series know, they both lived at High Towers, the estate of Jack’s father, near Nestorville. Jack’s father was an inventor of note, and in our first story, “The Boy Inventors’ Wireless Triumph,” it was described how the boys aided him in many stirring adventures in Yucatan and in the discovery of Tom Jesson’s long missing father, an explorer and naturalist. Since that time Mr. Jesson had made his home with his brother-in-law who, like himself, was a widower. The next volume detailed how Jack and Tom helped an inventor in trouble, and how, after many perils and difficulties, a wonderful vanishing gun was at length brought to perfection in spite of the machinations of a gang of rascals. This volume was called “The Boy Inventors’ Vanishing Gun.”

The third volume has already been referred to. It told how the boys had many exciting times under the ocean and on the surface. The Peacemaker was a wonderful craft and proved of material aid to some Americans beleaguered by blood-thirsty negro revolutionists in Cuba. Through the experiences related in this book both the boys increased their mechanical ability and learned self-reliance and manliness in many a hard test of both those sterling qualities. Had this not been so, it is doubtful if they would ever have had the grit to bring to a triumphant conclusion the construction of the Wondership, beset as their way was oftentimes by apparently insurmountable difficulties. But now, as we know, the Wondership lay finished before them. Already they had tested her in flight to ascertain how she bore the added weight. It was this trial, on which she carried side lights, like a ship, that had caused the flurry in the city papers. It had been a complete success, and only the trial by water remained.

Although Mr. Chadwick and Mr. Jesson knew that the boys were engaged on a supreme task, neither had interfered or asked questions. Jack’s father believed in letting his son solve his own problems. He knew that if occasion arose his advice would be called for. But the boys meant to fight out their battle alone. Even the test to take place that evening was to be unwitnessed, or so they hoped. Not till all was an assured success did they intend to invite their parents to inspect their work.

As the term at the Technical College was over, both boys had full time to devote to their work. All day they labored with paint brush and wrench, testing and finishing. They gave themselves little time for lunch, eating with one hand and working with the other. So engrossed were they on their tasks that they did not notice that the brightness of the day outside was being dimmed rapidly. A spring storm was rolling up from seaward.

Neither did they know that their work was going forward with attention other than their own concentrated upon it. The unseen observer had alighted from a car at its terminal some miles away and tramped across the sand dunes toward the big shed. Keeping warily out of sight he made his way up to the structure and, boring a hole in the planking, watched with burning interest all that was going on within. He was an odd-looking figure, dressed in a loud checked suit and sporting a gaudy necktie and a hat cocked to one side. But his youthful face bore an inquiring, good-humored expression that belied his aggressive way of dressing. Over one shoulder was slung a camera. As he watched the boys through the small hole he had bored with a gimlet that he carried in his pocket, the unseen observer muttered strangely to himself.

“By the double-jointed hoorah of the Sahara Desert!” he exclaimed from time to time. “Dick, my boy, you’ve struck it! Instead of being fired for incompetency, you’ll be the biggest reporter in Boston to-morrow. You’ve run the Mystery of the Skies to its roost,—by the long-legged Llama of Thibet, you have!”

All day he watched, his joints stiff and aching from holding the one position, but he never budged. It was growing toward dusk before he observed the change in the weather that had come with startling suddenness. The sea, calm before, was now roaring angrily on the beach beyond the dunes. The sky was covered with scurrying clouds. The wind moaned ominously.

The unseen watcher made a grimace.

“In for a wetting and three miles to that car,” he muttered, “but by the crooked cantelope of Cambodia, it’s worth it! Hullo! What’s that?”

From seaward there had come the heavy boom of a gun. About four miles off shore, dangerously close for that coast, there lay a white, yacht-like craft. Clearly she had fired the gun. Now she ran up some sort of signal.

“By the scampering snakes of Senegambia, there’s another story!” gasped the watcher. “I’ll be made a managing editor at least, by the time I get through.”
CHAPTER II. A SIGNAL OF DISTRESS.
“Hullo! What’s that?”

Tom set down his paint pot and listened intently. Jack crawled out from under the bottom of the Wondership which he had been coating with an extra application of waterproof bronze.

“Sounded like a gun,” he said after a second.

“It did, for a fact. Jove! Hark at the wind.”

As he spoke a gust shook the rather lightly-built shed.

“Must have come on a bit rough while we were at work,” commented Jack. “I hope it isn’t too squally for our trial trip.”

Whatever Tom might have responded to this speech will never be known, for at that instant came another report.

“B-o-o-m!” The echoes came dully shoreward, borne on a flaw of squally wind.

“It is a gun,” cried Tom, “but what in the world——”

“Let’s duck out and see. Hurry up!”

Jack made off and Tom followed. They did not go out of the front end of the shed, though big doors running on rollers opened to seaward. Instead they made for a small “accommodation” door in the rear of the shed. It was alongside this that the watcher had bored his observation hole. He had just time to slip around a corner and fling himself face downward in a patch of spiky sea-grass before the boys ran out.

“Lucky those kids didn’t see me,” he muttered. “I feel half ashamed of spying on them like this. But it’s all in the game, I suppose. If I don’t run down this assignment it means hunting another job, and I’ve worked on every paper in Boston but the one I’m on now; and I haven’t got the fare to go anywhere else job hunting.”

He watched the two boys run up to the summit of a big dune which commanded a broad view to seaward.

“By the horntoads of Herrington,” he exclaimed under his breath, “now’s my chance! I’ll get a few snaps while they’re out of the shed and then dig back. It’s taking a long chance and may be a rotten sort of thing to do, but I’ve simply got to make good.”

He rose from his place of hiding and, dexterously dodging among dunes and sand hummocks, made his way to the shed and darted inside by the small door from which the boys had just emerged. If he was surprised, he counted on managing to hide in some place of security till he got a chance to escape. Dick Donovan, cub reporter on the Boston Evening Eagle, was a young man of much resource, though at present hardly an example to be emulated. Still, as he owned to himself and as his editor had informed him that morning, it was a case of “making good” or getting what the editor termed the “G. B.”—which being interpreted, meant, as poor Dick knew only too well, the “Grand Bounce.”

As is the habit in newspaper offices, such a seemingly hopeless assignment as running down “The Mystery of the Skies” had been given to the cub reporter, the reason being that he might just as well waste his time on that apparently forlorn hope as on anything more promising. But Dick, who was by no means the “bone-head” his indignant editor mentally termed him, worked on the assignment like a beaver. He recalled hearing of the Boy Inventors and their various contrivances, and he formed a conviction that if he could run them down he would arrive at a point near to the solution of the mystery of the flying lights. It had been a matter of some difficulty to find out the present whereabouts of the boys, but the indomitable Dick had finally done it. His inquiries had led him to the lonely shed amidst the wind-driven dunes, and to the beginning of what he would have called “a galloping grasshopper of a yarn.”

As the boys gained the top of the dune they saw the yacht, standing out in white relief against the slaty background of cloud that rolled up from the east. She rose and fell slowly on the sullen sea, and they could see that a vagrant cloud of bluish smoke was rolling away from her. No doubt, then, that it was she that had fired the guns.

By some instinct Jack had snatched up a pair of glasses as they ran out of the shed. They were instruments used by the boys to scan anyone approaching their shed from a distance. He now turned these on the distant yacht. The next instant he uttered an exclamation:

“There’s trouble aboard out there as sure as you’re a foot high!”

“Can you make out what it is? They’re pretty close in, and those Baking Pan Shoals run out quite a way. Maybe they’re aground,” ventured Tom.

“No; it’s not that; at least, I don’t think so. There appears to be trouble on the yacht itself. She’s flying an ensign, Jack down, in her after rigging. Wow!”

“What’s up now?”

“There’s a chap trying to pull the ensign down!” cried Jack, with the glasses still to his eyes.

“Jove!” he rushed on, “there’s another chap pulling him away from the halliards. Now there’s a regular fight on! Say, Tom, that yacht’s just sizzling right now!”

“They need help.”

“Well, it sure looks so! Hullo, some men on the stern appear to have driven back the others, among them the chap who tried to pull down the flag.”

“It’s a sure thing, then, that there is some sort of mutiny on board.”

“Looks that way,” admitted Jack; “they fired those guns for help. I wonder——”

“I have it,” broke in Tom. “There used to be a life-saving station right here because of the shoals. It’s marked on the charts. Although it was abandoned two years ago, those fellows saw our shed ashore and they think it’s the life-saving station. It’s to us they’re signalling!”

“Christmas! I’ll bet you’re right. There’s nothing else in the shape of a house up and down the beach for miles, and the summer cottagers have not arrived yet. Yes, they’re appealing to us, Tom; but I don’t see what we’re going to do about it.”

“You don’t?”

There was an odd look in Tom’s eyes as he spoke.

The next instant there was a flash and a puff of smoke from the stern of the yacht, where Jack had made out some figures standing in a little group. The others had retreated forward. The report of the signal gun was borne to their ears a few seconds later.

“If only we had a boat,” burst out Jack. “I just hate to think of those fellows out there in trouble, and we not able to raise a finger to help!”

“Oh, but we are,” spoke Tom quietly. Jack looked at him swiftly and then almost involuntarily both boys’ eyes rested on the shed behind them.

“Jove, Tom! Have you got the nerve to try it?”

“Sure thing. We planned to make the test anyhow to-day. What better opportunity?”

“It’s blowing up for bad weather, Tom,” remonstrated Jack, who was far less impetuous than his cousin.

“Well, we’ve got to expect to get caught in that sometime. Besides, I don’t think it will blow very hard.”

Like many other people, men as well as boys, Tom had a way of minimizing obstacles when he wanted to do anything very much, and the scene on the yacht had aroused his curiosity to the utmost. Jack thought a minute and then scanned the sky carefully. Dark clouds were piling up and the sea looked leaden and ugly. The wind was not steady but came in sharp gusts and flaws.

“Maybe we’ve got time to get out there and back before it comes on real bad,” he admitted.

“Of course we have. Come on.”

Tom started on a run for the shed that housed the Wondership. As he went, he flung back word to Jack to “hustle.” From the ship came a fourth booming report.

“They’re watching us through glasses,” said Jack, as they ploughed through the sand. “They’ve guessed that we are going to help them somehow.”

“That means that we’ve got to make good,” was Tom’s comment.

They had almost gained the shed door when they saw coming toward them across the dunes a solitary figure, making its way with difficulty over the heavy sand.

“It’s dad!” cried Jack. “He has come to make us a visit, and left the machine back there on the road.”

“That’s so. It is Uncle Chester, sure enough,” assented Tom rather gloomily. “I guess our trial trip is off right now.”

“Yes; I don’t think he’d allow us to take out the Wondership in such weather as this promises to be,” agreed Jack with equal ruefulness. “Still, something should be done to aid those poor people out there.”

“Hullo! What’s the matter with him?” cried Tom in an astonished voice the next instant, for, on seeing the boys, the usually dignified Professor Chadwick had broken into a run. As he floundered along he was shouting excitedly words that they could not catch, and waving something in his hand.
CHAPTER III. AN AERIAL STOWAWAY.
Mr. Chadwick, breathless from his scramble across the dunes, met the boys in the shelter of the shed. They now saw that what he held in his hand was a despatch of some sort. He soon explained that it was a wireless message, relayed from the yacht Valkyrie,—via Sciuticut,—stating that his friend Professor Bismarck Von Dinkelspeil, on board the Valkyrie, was bound for South America on a scientific search of some sort, and intended to pay him a call at High Towers regarding the practicability of devising some sort of a novel boat. Details were not given.

“I hastened over here as soon as I got the despatch,” he said, “as I knew that you boys were transforming the Road Racer into some novel form. The Professor may be here to-morrow, and if you wish me to I’ll present you to him and you may be able to meet his demands. I’m too busy at present on that new steel reducing furnace to spare any time.”

“He gives no details?” asked Jack.

“No, as you see, it’s just a hurried despatch dated from his yacht. He is a celebrated man and has been all over the world on various scientific quests, in the interests of zo?logy mainly. But you boys look excited. What’s the matter?”

Jack speedily placed his parent in possession of the situation confronting them.

“The yacht is in need of aid, you think?” he asked when Jack completed a hurried and breathless recital.

“Without doubt. Hark! There’s another gun,” cried the boy. “I wish we could go to their help.”

“If we had a boat——” began Jack’s father. But the boy cut him short. Without further delay he plunged into an explanation of the Wondership. Mr. Chadwick looked amazed for an instant, but then his face resumed its customary air of studious calm.

“You think your device will work?” he asked, regarding Jack keenly.

“I’m sure of it. In fact, we have buoyancy to spare. On paper——”

“Paper and practice are different things, my boy.”

“I know, sir, but——”

“You see, there are human lives at stake out there. It’s worth risking,” broke in Tom, unable to keep silence any longer. “Can’t we go?”

Mr. Chadwick considered an instant.

“Let me take a look at your ‘Wondership,’ as you call it,” he said.

With what rapidity Jack exhibited the craft and showed off her good points may be imagined. While they were thus engaged there came the sound of another gun. Then Mr. Chadwick spoke.

“Is everything ready?”

“Down to the last nut on the ultimate bolt,” declared Jack.

“Plenty of gas?”

“A reservoir full and more gas-making stuff in the reserve chamber.”

“Very well, then. I’m ready when you are.”

And without any more words Mr. Chadwick climbed into the machine, using in his ascent a small ladder set against the gleaming metallic sides. The boys exchanged glances. But they didn’t make any comment. It was not a time for words. While they waited even, events might be transpiring aboard the strange yacht of an unknown, possibly tragic, nature.

“Open the doors, Tom,” ordered Jack, in a voice that sounded like anybody else’s rather than his own.

Tom hastened to obey. The big panels in front of the shed rolled back. The opening thus revealed framed a wild sea-scape of rising waves, overcast sky and, in the center, the yacht, her reversed ensign making a bright splotch of color against the leaden background. But as yet the wind was merely puffy, and not blowing with dangerous strength.

Having opened the doors, Tom hastened back. He climbed in by Jack’s side.

“Are we all ready?” he asked, with a gulp. In his excitement his heart was bounding with sufficient velocity to be uncomfortably evident. But he managed, by an effort, to keep calm, or rather to appear so.

“As ready as we’ll ever be, I guess. Be ready to lower those hydroplanes when I give the word.”

Tom nodded. The hydroplanes worked on toggle-joints and could be lowered and locked when required. This was a part of his duty that the boys had already rehearsed. Jack’s hand sought a lever. A hissing sound followed. The gas was beginning to rush into the big gas-bag. Its folds began to puff out and writhe as if some living thing was within it.

“I’ll start when it is half full,” announced Jack in a sober voice.

“How’s the pressure?” inquired Tom, whose face was pale.

“Fine; a trifle over five hundred pounds. We’ll fill quickly on that.”

In the rear seat, which might be likened to the tonneau of an auto, sat Mr. Chadwick. Not a trace of emotion was visible on his strong features. Through his spectacles he eyed the boys’ preparations with interest. It was by no means his first trip in the Flying Road Racer, as he still called it, and he knew that the boys thoroughly understood her management. Therefore he did not embarrass them with questions or suggestions.

“That’s enough,” announced Jack presently, when the bag was almost full, “that will lift us and I’ll fill out the wrinkles while we are in the air.”

“You’re going up first, then?”

“Of course. That will give you a chance to get over your ‘rattles’ before we drop.”

“Rot!” vociferated Tom indignantly. “I’m not rattled a bit.”

But his shaking hands and shining eyes belied his words. If not “rattled,” Tom was considerably excited. Jack, on the other hand, although his pulses were throbbing uncomfortably fast and a large lump appeared to have clambered into his throat and stuck there, was outwardly as cool as ice.

“Ready, Dad! I’m going to start! Hold tight!”

“All right, my boy. Go ahead as soon as you’re ready.”

Jack pressed a button on the steering pillar. The self-starting mechanism, operated by the same storage batteries that ran the lights and the ventilating fans, whirred loudly in response. An instant later he applied the gas. A volley of explosions followed. The shed was filled with an odd, sickly odor.

Again Jack’s hands flew, and with a jolt the Wondership leaped forward, rumbling over the wooden floor.

Straight out toward the sand dunes she rolled, her engine pulsing like a throbbing human heart. The light but strong framework vibrated under the strain. The great propeller of magnesium-vanadium metal became a mere shadowy blur.

Outside the shed a sort of runway had been built leading down to high water mark. As the odd craft rushed toward the waves Tom was conscious of a queer feeling, centering at the pit of his stomach.

“Guess I must be scared,” he snorted indignantly to himself, and then broke off with a sudden exclamation.

“What’s that?”

“What’s what?” came from Jack, who was busy adjusting levers and buttons.

“Why, that.”

As he spoke, both boys became aware of an odd sort of muffled sound, coming seemingly from under the seat on which they were stationed.

“Something’s wrong with the machinery,” cried Tom, as the odd sound came again.

“Can’t be. She’s working like a clock,” rejoined Jack. “Hold tight,—we’re going up.”

As Jack spoke, he applied a full stream of gas to the limp bag, and the Wondership shot upward with the swiftness of a rocket. A gust of wind struck them and sang weirdly through the rigging and supports. But the craft never wavered on her course. As she shot upward, though, from the yacht, heard above the hum and buzz of the machinery, came the sound of another gun.

“They’re wishing us luck!” cried Jack.

“We’ll need all we can get,” came a voice. “By the bounding brown buffaloes of Brunswick, this is the limit!”

“Hullo! What’s the matter with you, Tom?” cried Jack looking around in astonishment, as he manipulated the craft with a skill born of long practice.

“I didn’t speak, Jack. It was that same mysterious voice. This craft is haunted, I believe.”

“Nonsense. We must be imagining things,” declared Jack; “but I’m almost sure I heard a voice.”

“So am I. How is she working, Jack?” asked Tom, dismissing the subject. He thought that his overwrought nerves were at work.

“Finely. I’m heading straight for the yacht. I mean to circle her and then,” he paused an instant and added, “drop!”

Jack now pushed the craft ahead at full speed. Faster and faster she went. Far below them lay the sullenly heaving ocean. Beyond, but very close now, was the yacht.

“All right, Tom. Get ready now.”

Tom jumped to his work. In a few seconds the novel aluminum hydroplanes were adjusted and fixed in place. The yacht was right below them now, but the figures on her deck were dwarfed to pigmies. Jack set the suction pump to work, reducing the gas supply in the bag.

Slowly at first, and then faster, the great air craft began to fall toward the gray sea. The propeller ceased revolving. In almost total silence, except for the boys’ quick breathing, the descent continued. Suddenly a wild cry split the air. It appeared to come from the Wondership itself.

“Let me out! Put me ashore! By the buck-jumping broncos of Butte, I wasn’t born for a watery grave!”

“Gracious!” cried Jack, in a startled tone, as a head of red hair poked itself out from under the seat, “we’ve got an aerial stowaway aboard!”
CHAPTER IV. INTO THE THICK OF IT.
For the moment, the affairs of Dick Donovan,—our readers will have guessed that this first aerial stowaway on record was the young reporter,—had to wait. This drop through space was too thrilling, daring, dangerous for anyone on board to pay Dick more than passing attention. There was not even time to ask him who he was.

Indeed, at the instant that Dick, who had hidden in the machine without any idea that immediate flight was to be undertaken, made himself known, peril loomed swiftly and ominously before them.

As they swooped downward, like a giant fishhawk diving after its finny prey, there was a sudden shout of alarm from Tom. The great airbag swung to one side, dragging the carriage of the flying machine with it in a dizzying swerve.

“Look out!” shouted Tom excitedly.

There was no need to ask him the cause of his sudden alarm. The Wondership, yawing before a sharp flaw of wind which came too suddenly for Jack to counter it, was being driven straight for one of the slender, sharp-topped masts of the yacht.

“Keep her off!” shouted Mr. Chadwick, half rising, “we’ll rip the bag open if you don’t look out.”

Jack’s lips set grimly, determinedly. With a swift motion of his hand he applied power. The propeller began to whirl, forcing the wind-driven craft away from the peril of the mast. Dick Donovan, in frank terror, shouted aloud.

“Gracious! We’ll strike!” was the cry forced from Tom’s lips.

The next instant, despite Jack’s prompt action, the Wondership, deliriously sagging and swaying, crashed against the tip of the yacht’s after mast.

Ri-i-i-i-i-i-i-i-i-p!

The steel tipped weather-vane that was fixed on the top of the spar had penetrated the midship section of the bag and inflicted a bad tear in it before Jack had had time to hold the big craft off. The propeller had been set in motion an instant too late. With a vicious hissing sound the gas rushed from the rent as the Wondership, the mischief done, careened drunkenly away from the mast that had inflicted the wound.

There was a sudden, appalling dash downward. A stone from a roof could not have fallen much faster. Amidst a shout of alarm from the yacht’s decks, which was echoed by those on the Wondership, she struck the sea with a force that sent spray and foam half way as high as the vessel’s mast heads.

In the dreadful moment that succeeded, it seemed as if the craft must go crashing down to the very floor of the ocean. But a fraction of a second later those on board both Wondership and yacht knew that this was not to be the case.

Having struck the water, the hollow hydroplanes and the water-tight body of the craft fulfilled their purposes right nobly. Buoyed on the crest of a big swell, the Wondership floated, and the next instant, amidst a cheer of more than ordinary fervor, Jack started her for the yacht’s side.

“Hurrah! She floats!” yelled Tom.

“By the galumping galleons of Gaul, she does that!” agreed Dick Donovan, against whose pale face the freckles stood out like spots on the sun.

“But will she move?” cried Mr. Chadwick, as the propeller began to churn the water.

“We’ll soon see,” answered Jack over his shoulder.

As the blades bit into the water the Wondership was drawn forward, slowly at first and then, gathering speed as she crossed the space intervening between herself and the yacht’s side, the Wondership was seen to adapt herself to the water as well as she had to the earth or the air. A moment later, skillfully manipulating his rudder, Jack brought the strange craft alongside the yacht’s lowered companionway with as much skill as any veteran mariner making a familiar landing.

To reach the gangway from the spot at which the Wondership had struck the water, they had to pass her stern. On the graceful, narrow counter of the craft was much gilt scroll-work and ornamentation. Amidst all this “flummery,” as sailors call it, they made out a name and hailing port.

“Valkyrie-of-Bremen,” was what they read.

As his eyes encountered the name, Mr. Chadwick gave a gasp.

“Why,—why! This is most extraordinary!” he cried in frank amazement. “This is the very yacht from which my wireless message was relayed from Sciuticut!”

“They must have been trying to make for the mouth of the Nestorville River when whatever is the matter on board, came up,” commented Jack.

But by this time they were at the gangway and conversation ceased for the time being. They could see several heads poked over the side, eying them curiously. As they came alongside, a stockily built man with a bristling straw-colored moustache descended the gangway stairs.

He wore a blue coat with brass buttons and appeared to be in authority.

“What’s the trouble?” demanded Jack eagerly, as the man came nearer.

“Good. You saw our signal for aid, then?” he said with an odd sort of hesitation. “You come near wrecking that contraption, just the same,” he added. “What kind of a craft is it?”

“Never mind that now,” exclaimed Mr. Chadwick impatiently. “The question is, do you need help? Are you aground, or what?”

“No, it ain’t that exactly,” said the man slowly; “it’s trouble of another sort.”

“Is this Professor Von Dinkelspeil’s yacht?” asked Jack quickly.

“Sure. Yes, it’s his yacht, all right,” was the odd reply.

“Is the Professor on board?” asked Mr. Chadwick. “He’s a friend of mine, and if he is in any difficulty we shall be glad to do anything in our power to help him out.”

Again the man hesitated. While they had been flinging questions at him he had been joined by another man, a rough looking specimen, clad in a semi-nautical costume. He now turned to this man and they whispered together for an instant. Then the bristly-moustached man turned to our party.

“The Professor is on board,” he said, “but I don’t know if you can see him.”

“Why not?” demanded Mr. Chadwick crisply, with rising irritation. “You signalled us for aid, we came out here at considerable risk and, in fact, have seriously damaged our craft. If the Professor is on board, I think he owes us an explanation.”

Once more there was a whispered conversation.

“There’s something extremely odd about all this,” said Mr. Chadwick to Jack in an undertone. “I can’t understand it at all. I——”

“The fact is,” broke in the bristly-moustached man, “the Professor has met with an accident. But perhaps you had better come on board and see him for yourselves.”

“I guess that would be the best plan,” said Mr. Chadwick. “Boys, you wait here. I’ll be back before long.”

“I don’t half like the look of this,” muttered Jack. “There’s something here that isn’t all right. Let me go with you.”

“No, my boy. You stay where you are. I’ll be back before long. I can’t imagine what can be the matter; but whatever it is, I can take good care of myself.”

With these words Mr. Chadwick sprang to the platform of the gangway, and under the guidance of the two men he made his way up the steps. An instant later he was gone from view.

The boys exchanged glances.

“Well,” blurted out Tom, “if this doesn’t beat the band! These fellows waste powder enough for a Fourth of July celebration to summon aid, and when it comes they don’t appear to know whether they want it or not.”

“Looks mighty fishy,” admitted Jack. “I wish Dad had let me go with him. But see here, Tom, we’re forgetting all about our stowaway. Say, who are you, anyhow?” he demanded, turning to Dick Donovan and scrutinizing him sharply. Dick looked considerably abashed.

“I guess it’s up to me to make explanations,” he said. “My name is Dick Donovan. I’m a reporter. I was told to run down the ‘Mystery of the Skies’ or get fired. I sneaked into your shed when you went out to take a look at this yacht, and then when you came back unexpectedly while I was snapping your machine, I got rattled and hid under the seat. Wow! By the sky-scraping sultans of Syria, but you gave me a royal old scare!”

“That is nothing to what you are going to get if you write a line about all this in your paper,” snapped Tom. “What do you mean by playing the sneak about our work-shed and spying on us,—eh? What do you mean by it?”

He doubled up his fists threateningly; but Dick Donovan only smiled.

“Don’t get mad,” he said. “I’ll admit it wasn’t the right thing to do, and you chaps appear to be pretty white and I’m ashamed of myself for spotting you.”

“You ought to be,” growled Tom.

“Wait a minute,” put in Jack soothingly. “Go on,” he remarked to Dick Donovan.

“Oh, well, all I wanted to say was this,” said the reporter, getting very red. “You needn’t be afraid that I’ll write a line about this thing, because I won’t. I can get another job somehow, I guess, and anyhow I’ve had enough experience crammed into this last half hour to be able to sit down and write a novel.”

The impulsive Tom’s manner changed in a jiffy.

“Say, you’re all right, Donovan,” he exclaimed, “and—and I tell you what, when we get this thing perfected we’ll give you the first news about it,—a scoop, don’t you call it?”

Dick’s amiable face beamed broadly as Jack nodded his assent to Tom’s promise.

“Say, that’s bully of you!” he cried boyishly, extending his hand. “I don’t want you to think I’m a bounder just because I came peeping and peering about your shack back there. I didn’t look at it from your point of view. I——”

He broke off abruptly. His lower jaw remained dropped just as it had been as he was about to continue speaking. At the same instant both the Boy Inventors sprang to their feet.

It was a startling enough interruption that had occurred to cut short Dick Donovan’s contrite speech.

From the decks of the Valkyrie there had come the sharp, ringing report of a pistol.

It was followed by shouts and a loud tramping of feet on the planks above them. Jack paused a second for thought and then, grabbing up a monkey wrench and calling to the others to do the same, he jumped for the companionway.
CHAPTER V. MUTINY.
As the three boys, for Dick Donovan brought up the rear, sprang up the gangway steps the burly figure of a sailor suddenly blocked their way.

“You kids keep out of this,” he admonished, and tried to push Jack back.

The boy’s fist shot out and the sailor, caught fairly on the point of the chin, fell in a sprawling heap. Jumping over his prostrate form, as he lay there swearing and trying to regain his feet. Jack and his companions gained the deck.

The first thing their eyes fell upon was Mr. Chadwick struggling in the arms of several sailors. Jack reached the deck just in time to see a noose thrown over his father’s head, making him a helpless captive as it was swiftly drawn down and pulled tight about his arms.

“Let my father go!” shouted Jack angrily, springing forward.

The bristly-moustached man stood in his way. As the boy rushed forward the man thrust out his foot and Jack fell in a heap. In an instant the sailor pounced on him. But Tom, with a shout, pitched upon Jack’s captor. In a flash they were rolling all over the deck.

Jack regained his feet as the heavy form of his captor was removed. Dick Donovan was at his side.

“I’m with you, by Barataria,—I’m with you!” he cried, throwing himself into an attitude of defense as several men ran toward them. Tom had by this time managed to throw off the man whom he had attacked and, springing to his feet, he joined his comrades. The three boys, their backs to a deck house, faced the crew of the yacht without flinching; but their faces had grown deadly pale. Mr. Chadwick had been dragged off and was not to be seen.

The bristly-moustached man got to his feet and glowered at the boys menacingly. Under one of his eyes, so Jack noted with satisfaction, was a rapidly-spreading, plum-colored bruise.

“Now see here, you kids,” he barked out, “it ain’t a bit of good, your putting up a scrap. Your dad tried it and it took a bullet to stop him.”

“You rascal! You wounded my father?” shouted Jack, rushing at him, completely carried away by anger.

But he had not advanced a foot before he was seized by a dozen of the crew who, despite all his struggles, held him fast.

“You see it ain’t a bit of use, your kicking,” went on the man, vindictively. “This yacht carries a crew of twenty men and they’ll all do just as I tell ‘em to. Now that you know what you’re up against, I’ll explain a few things to you just to show you that there’s nothing you can do against my wishes.”

Despite their indignation, the boys listened eagerly for what was to come. Tom and Dick still held their attitudes of defense. Poor Jack was too effectively held to do anything but submit, with what grace he could.

“Them guns you heard was fired by the Professor’s orders. He figured there was a bunch of life savers ashore who’d come out and clap us all in irons for mutiny. We rushed him and finally he saw it was no go and gave in. He’s a prisoner in his cabin now.

“If you and your dad hadn’t come butting in in that contraption of yours we’d have gone on our voyage all peaceable; but you interfered, and now you’ve got to pay for it. If we let you go ashore you’d get the gov’ment after us and we’d get in hot water. As it is, we’ll just lock you up till we make up our minds what to do with you, and then we’ll dispense with you someway.”

“Is my father hurt?” demanded Jack.

“No, he’s all right and will be all right as long as he keeps quiet. I fired a shot at him to keep him quiet, scare him like. That’s all. You can take ‘em below, men, an’ then we’ll keep on our course.”

“But our ship!” cried Jack, anxiously. “What’s going to become of that?”

“Oh, that blamed contraption? Well, that can just as well go to the bottom as not, I guess. Take ‘em away, you fellows.”

Jack, half crazed at the last words of the rascal, was dragged helplessly off. Tom and Dick made a feeble show of resistance, but they, too, were speedily captured and hauled across the deck after him. Unarmed as they were, they had no chance of putting up any fight. And so, within an hour after they had set out to answer the call for assistance, they found themselves prisoners and their Wondership doomed to destruction. No wonder that their hearts felt like lead as their captors roughly shoved and pulled them along.

In this way they were propelled down a flight of steps leading, as soon became apparent, into the saloon of the yacht. From this chamber there opened off several smaller doors. One of these was open and through this and into a small cabin the boys were roughly thrust. Then the men who had made them captive went off without a word, first locking the door behind them on the outside.

The boys looked miserably at each other as the door clicked.

“Prisoners!” exclaimed Jack.

“And the Wondership to be cast away,” cried Tom despairingly, sinking down on the edge of a bunk. “There’s all our work and money gone for nothing,” he added bitterly.

Dick Donovan said nothing. He felt that of them all he was the only one who had no right to say anything. He was there by his own fault solely, and the freckle-faced boy felt that it would have been an impertinence on his part to have made any complaint.

“Well, this is a fine fix,” exclaimed Tom at length, after a long silence, during which they had heard a trampling of feet on deck but had noticed no vibration to show that the yacht was in motion.

“Yes; and that there is so far no explanation for our treatment doesn’t make it any better,” spoke up Jack wretchedly. “It’s the thought of the Wondership being cast loose that makes me feel worst, though.”

“Same here,” muttered Tom dismally; “but can you form any idea as to why we’re being treated in this way?”

Jack shook his head.

“It’s all a Chinese puzzle to me,” he said. “Of course, that ruffian on deck hinted that there had been a mutiny of some sort, and that between the time that we answered the signal guns and the moment we reached the ship the Professor had been made prisoner.”

“Didn’t you see a struggle to pull down the flag when you looked through the glasses?” asked Tom.

“Yes, two or three men on the stern deck appeared to be battling with some others whom they finally drove off.”

“Then depend upon it, the whole crew has not mutinied. Probably the men you saw were the Professor and the Captain or some other officer who had remained loyal,” struck in Dick Donovan. “Come to think of it, I believe I saw a despatch in the paper some time ago about this very yacht,” he went on. “The cable came from the Canary Islands and said that the Valkyrie had put in there with a mutinous crew and shipped another one. She then proceeded on her voyage across the Atlantic. There was some mystery about her destination, but it was generally supposed that she had on board a party of treasure hunters bound to recover lost treasure somewhere in South America.”

“From what I’ve heard dad say about Professor Von Dinkelspeil,” said Jack, “I don’t think the professor is much of a chap for that sort of thing. Dad said that he was a famous naturalist.”

“Maybe he was going to combine natural history and treasure hunting in South America,” suggested Dick. “Anyhow, one thing is sure; for some reason this new crew has mutinied like the old one. They now have possession of the ship and we are their prisoners. The question is, what are they going to do with us?”

Dick’s clear way of putting it made them all look serious. It was plain enough that, after treating them in the manner that they had, the mutinous crew could not afford to chance setting them ashore. In that case their ultimate fate remained a mystery.

“What do you think about it?” asked Tom, turning to Dick. In some way he felt that this bright-eyed, alert lad was more likely to have the key to the situation than any of them. But Dick shook his head perplexedly.

“What they mean to do with us depends a heap on what they intend to do themselves,” he said dubiously. “It’s my idea that, right or wrong, the rascals now in control of this craft must have had some sort of idea that she was on a treasure hunt. In that case, I think it’s likely that they may have secured in some way information as to where the treasure is, and are going after it themselves.”

“Then I wonder what they will do with us?” insisted Tom.

“By the grinning gondoliers of Granada, you’ve got me stuck. Maroon us, maybe, on some island, or——”

“Hullo! We’re moving!” cried Jack suddenly.

A perceptible vibration and hum ran through the yacht’s frame as her engines began to revolve. There was a port-hole in the cabin in which the boys were confined and Jack thrust his head out. But he could see no signs of the Wondership. Instead, through the rain which was now falling fast on a sullen, heaving sea, he could perceive, dimly, the distant coast line slipping by.

It was at this juncture that an odd sound came on the wall of the cabin.

“Somebody’s tapping!” exclaimed Tom, the first to solve the mystery.

“Sure enough,” rejoined Dick; “maybe it is your father. They may have put him in next door.”

“Hark!” exclaimed Jack suddenly. “Listen to those taps. Don’t you notice something odd about them?”

They listened in silence for a few minutes. Above the throbbing of the screw and the rush of water along the moving vessel’s side they could catch the odd rhythm of the taps being delivered on the cabin wall.

“By the ticker-tapes of Tripoli,” cried Dick suddenly, “somebody’s telegraphing us!”

“Yes; it’s the Morse code!” almost shouted Jack, and leaning against the wooden wall of the cabin he energetically rapped out a reply.
CHAPTER VI. A STORM AT SEA.
In fifteen minutes or so the boys learned, by means of this novel method of telegraphy, that in the next cabin to them were imprisoned Mr. Chadwick, Professor Von Dinkelspeil and Captain Abe Sprowl, the skipper of the yacht. As we already know, both our lads were experts at the key, as was their father, and Dick Donovan had picked up enough of the art in newspaper offices to be able to understand at least part of what Mr. Chadwick was signaling.

It naturally took some time to place them in full possession of all the facts pertaining to their uncomfortable position, but by degrees they were told all that Mr. Chadwick knew of the case. The crew of rascals at present in possession of the yacht was the same outfit that had been shipped hurriedly at Madeira. Either out of maliciousness, or because they really believed it, certain members of the old crew had told the new hands that the professor was off on a hunt for fabulous treasure on the Spanish Main.

Trouble had broken out in mid-ocean. The crew had sent a committee to the professor formally to demand a share in the treasure. This, of course, had been denied for the very excellent reason that the trip was not making a treasure hunt. Its object was purely scientific, its destination, that naturalists’ paradise, the Upper Amazon. But the crew, their minds inflated by hopes of gold and jewels, professed to believe that they were being tricked. No words of Captain Sprowl, an old Yankee mariner, could convince them to the contrary. Under the leadership of Mart. Medway, the bristly-moustached man, and Luke Hemming, his lieutenant in mischief, they had been ugly for weeks.

This led to Captain Sprowl’s bluntly telling them that on arrival in America, to which he was shaping his course for that purpose, they would all be discharged and new men taken on in their places. This did not suit the men at all. Driven wild by dreams of wealth they broke into open mutiny a short time after the professor had sent his wireless despatch to Mr. Chadwick. Led by Medway and Luke Hemming, they insisted that the yacht be held on her course for South America. A refusal to do so resulted in so much trouble that the yacht had been navigated as close to the shore as was safe, and the guns fired for aid when they saw in the distance what they thought was the Baking Pan Life Saving Station. What followed then, we already know.

Of course it took a long time to explain this with the primitive means at the command of those who had so unexpectedly got into communication. It was a matter of vast joy to Jack, though, to know that his father was uninjured and in good spirits, although, so Mr. Chadwick had tapped out, those on the other side of the partition were as much in doubt as to their ultimate fate as were the boys themselves.

By the time it was deemed prudent to cease communication for the time being, there was an angry sea running outside. Once a big green wave climbed the yacht’s side and swept in a torrent into the boys’ cabin. They had to close the port-hole and this made the tiny place almost insufferably stuffy. The motion, too, of the yacht as she plowed through the rising sea made Dick feel uncomfortably squeamish. Luckily, both Jack and Tom were good sailors and felt no inconvenience.

Night had fallen and the cabin was plunged in darkness, but nobody came near them. There was an electric globe in the cabin, but when Jack tried to turn it on he found that the current had been cut off. From outside the door they could hear the buzz of voices, but were not able to distinguish words. Presumably Medway and Hemming were in consultation. But even though the boys tried their utmost to hear something, hoping that it might shed some light on their ultimate destiny, the complaining of the laboring ship and the low tone in which the men’s voices were pitched, prevented any eavesdropping.

And so the hours wore on, the prisoners from time to time communicating by tapping in the Morse code. This, in itself, made the dreary, dark hours more endurable for the boys. As it grew later it was evident by the frantic pitching of the yacht that a tremendous sea must be running outside.

From time to time they could hear the rush of heavy feet on the deck overhead and thought they could catch the sound of hoarse shouts.

“Gracious!” exclaimed Tom, after an unusually heavy lurch had sent him staggering across the cabin, “there must be a whopper of a storm outside.”

“Yes, indeed,” agreed Jack, “she’s pitching like a bucking bronco. Wow! Feel that!”

The Valkyrie appeared to climb heavenward, pause for a thrilling instant, and then rush down—down—down as if she would never stop.

“Oh-h-h-h-h-h!” groaned Dick in an agony of sea-sickness, “is she going to the bottom?”

“No danger of that,” responded Jack with a confidence he was far from feeling, “this old tub has been around the world before now, and an off-shore gale isn’t going to finish her.”

“Wo-o-f!” groaned Dick, “I wish it would. This is what I get for snoopin’ around where I have no business to be. Oh-o-o-o-o!”

All at once there came to them, above the uproar and confusion of the storm, the sound of the “telegraph” at work. Jack was alert in an instant.

“What is it?” he tapped back.

“The professor says,” came the reply, “that the cabin next to you on the other side and the one you are now in used to be all one stateroom. A partition was put in some time ago of which the new crew knows nothing. It was so fitted that it could be moved out if necessary. Maybe if you can find out how it works,—he has forgotten,—you can get out when the time arrives.”

This was news indeed. There was, then, a way of escape out of their prison if they could find it. But with a moment’s reflection came another thought.

Even if they did get out, they could do nothing against twenty men and two officers. But, just the same, Jack made a mental note of the information, resolving to investigate. A time might come, as his father had suggested, when they could put it to practical use. That day was to come sooner than any of them expected.

But until dawn brought light it was useless to think of examining their prison. The darkness that enveloped them was velvety in its denseness. Only by a sense of touch could they find their way about. And so, tossed and tumbled by the violent motion of the yacht, faint and heart-sick from want of food and doubt as to what was to become of them, the boys passed the night as best they could. At times they slept fitfully, only to waken to hear the shrieking of the wind and experience the sickening plunges of the buffeted yacht.

The first chilly gray light that preceded the dawn was stealing into the cabin when, without warning, the motion of the engine suddenly stopped. They felt the yacht struggle like a wounded thing as the seas broke over her. Then her motion changed. Like a water-logged craft she began to tumble and roll in the trough of the waves.

“Are we sinking?” cried Tom, wakening from a doze with a start.

“I don’t know what’s happened,” rejoined Jack, “but it looks to me as if the machinery had broken down.”

“In that case we’re in a mighty bad fix?”

“About as bad as we can be. A few hours longer in the trough of this sea will break us up and send us to the bottom.”

The boys regarded each other with white, frightened faces. There was something terrifying in the realization that the yacht had ceased to struggle with the waves. It was as if, despairing of weathering the storm, she had given up the struggle.

Suddenly the door was flung open. The form of Medway, shrouded in dripping oil-skins, stood framed in the doorway. He looked haggard and worn and, at least so Jack thought, not a little frightened.

“You kids understand machinery?” he asked roughly, holding on to the door-frame to steady himself against the yacht’s crazy rolls.

“A little,” responded Jack.

“Then come with me, and no monkey tricks if you want to get out of this alive,” he shot out, brusquely.

“Only you two. Not that red-headed kid,” he added, as all three of the boys arose to follow him.
CHAPTER VII. THE BOYS FIND NEW JOBS.
Wonderment was the feeling uppermost in the minds of both Jack and Tom as, clutching at hand-holds and rails, they followed their conductor. He led the way up the companionway and to the deck, with a gruff caution to “hang on” when they came into the open.

The warning was necessary. A wind that seemed to force their breath back down their throats was sweeping across the sea, which, running mountain high, looked grim and pitiless, under the pallid gray dawn. No land was in sight, nothing but giant combers amidst which the yacht seemed no more than a helpless chip. Looking at the sea the boys found themselves wondering how the craft had kept above water as long as she had. But almost immediately when they emerged on deck their attention was distracted from the sea and from every other impression but one.

Lashed firmly to the boat deck on top of the main cabin house, was an object that made their hearts give a glad bound.

The Wondership, securely lashed, had been hoisted there and, so far as they could make out, no damage had been done her.

Jack gripped Tom’s arm.

“She’s all right, after all,” he exclaimed hoarsely, as if that was the only thing that really mattered.

Tom decided to venture on a question.

“You hoisted her on board?” he half shouted above the screeching wind to Medway.

“Yep,” was the brief reply. “Thought we might use her someway, so we made a tackle fast under her and hauled her aboard by the main cargo derrick.”

“That was mighty decent of you,” cried Jack warmly.

“Don’t fuss yourself,” was the rough rejoinder, “it warn’t done to please you.”

As Medway spoke, he turned into a doorway in the after part of the cabin house. From the hot smell of grease and oily machinery that arose from it, the boys knew that it led to the engine-room. They climbed down a steel-runged ladder and soon found themselves amidst a maze of polished rods, cams and levers. But the triple expansion engine was idle.

Hardly had they had time to notice this, when they saw that on a leather-covered bench set against the steel wall a man was reclining. His face was white and covered with sweat. His hand was bandaged and one of his legs was doubled up. From his expression of mute agony it was plain that he had been painfully injured.

“Judkins, the engineer,” explained Medway, with a sidewise jerk of his head. “Condenser went out of business a while ago. He got busted tryin’ to fix it. Think you boys can run this engine?”

Jack looked dubious. Tom said nothing.

“I can give ‘em a hand,” said Judkins in a weak voice.

“That’s enough then,” said Medway briskly, as if it was all settled. “Understand,” he said, turning to the boys, “it’s a case of life or death. The sea is increasing. If we don’t get going pretty soon, it’s down to Davy Jones for all of us.”

“But we don’t know anything about steam engines; very little, that is,” protested Jack, although both boys had, in addition to their other studies gone in for a course of steam engineering at the “Tech.” But that course, a sketchy one at best, had only comprised stationary engines.

“Well, Judkins can tell you what you want to know. The first thing to do, I guess, is to get that condenser going.”

“I had her going when I slipped and fell under the crank shaft,” said Judkins weakly. “All she needs is a union on that copper piping and she’ll be all right.”

He indicated the condenser and the place where the union would have to be attached.

“There’s a tool kit and fittings yonder,” he said, pointing to a bench affixed to the bulkhead that divided the engine-room from the stoke hold. A glance at the gauges affixed to this showed Jack that, at any rate, they had a good head of steam. The high-pressure boilers of the Valkyrie were carrying one hundred and seventy-five pounds.

Medway saw his glance.

“Lots of steam,” he vouchsafed; “only thing to do is to get her going. Remember, it’s that or the bottom of the deep blue sea.”

For reasons that the boys did not learn till later, the Valkyrie did not carry an assistant engineer. When the old crew had been set ashore at Madeira there was no chance to secure such an officer, and so she had proceeded to sea with Judkins as the only skilled man in her engine-room. No doubt it was the severe strain he had been under that had caused him to become careless and receive the injury which had disabled him.

Jack’s natural quickness at mechanics enabled him to see what was required on the condenser after a few words of explanation. This done he and Tom ascended to the starting bridge and applied steam to the engines. It was no easy task to carry out these operations on the rolling, wallowing yacht. But at last, as Jack turned on the steam and Tom applied the starting power, they were rewarded by the sight of the cranks slowly revolving.

Suddenly a loud clang close by his head startled Jack.

“All right, come ahead!” hailed Judkins, “Easy now!”

Medway in the pilot house had felt the quiver of the started engines and had given the signal. Jack allowed the engine to pick up revolutions gradually until, at half speed, they were heading into the big seas with the screw turning regularly and powerfully. When this was done Judkins closed his eyes, lay back, and slipped off into unconsciousness. Tom, alarmed, ran through the bulkhead door into the fire-room. Here he found the stokers at work. There were three of them and he sent one on deck after Medway. It was plain that something would have to be done for Judkins at once. Medway soon appeared. It seemed that the man, in a rough way, was a bit of a surgeon. At any rate he declared that he could care for the injured man and had him carried above by two of the crew.

Not long after, the same two men appeared with food for the boys. They did full justice to the meal, unembarrassed by their queer situation. After it had been despatched, Jack noticed Tom’s sleepy looks. In fact the younger of the two lads could hardly keep his eyes open.

“You lie down on that bench and take a nap,” ordered Jack, “I’ll stand watch.”

“But what about you?” inquired Tom drowsily.

“Oh, I’ll be all right. Just you lie down now and I’ll wake you in a couple of hours. I guess we’ll have to hold down this job for some time and we might as well go at it scientifically,” was Jack’s rejoinder.

Five minutes later Tom’s snoring was keeping time with the rhythmic pulsing of the engine as the Valkyrie battled with the storm.

CHAPTER VIII. “THIS IS THE FINISH.”
As Jack had prophesied, they did have to “hold down the job for some time.” In fact, dating from the morning on which Medway escorted them to the engine-room of the Valkyrie, the two boys entered on what was perhaps the strangest period of their lives in many respects. Virtually prisoners, they yet found a certain pleasure in oiling, running and ministering to the big engine. Their innate love of machinery found full play during the following days and nights.

The gale blew itself out after two days, but they still were kept at their posts. Medway had ordered two cots provided for them, and their meals were served below. On trying to reach the deck for a breath of air, after a long vigil at the engine, Jack found that the engine-room was well guarded. At the door was stationed a husky sailor who roughly told the boy to “get back where he belonged.” He had no choice but to obey.

In this way the days went by, the boys taking watch and watch, four hours on and four off. Medway or Hemming visited them regularly, but made no comments, nor did they vouchsafe any information as to the whereabouts of the yacht. Had the boys only known how the other prisoners were faring, and what was ultimately to become of them all, they might have been almost happy in their jobs as young engineers. But as things were, their constant anxiety on these scores outweighed any pleasure they found in running the machinery of the yacht.

Judkins evidently was still confined to his bunk. At least he did not put in an appearance. And so, day after day went by and the yacht forged steadily on, and the boys, working in the engine-room, had no means of knowing her course or destination; for, unlike some craft, the Valkyrie carried no “tell-tale” compass in her engine-room.

Thus two weeks passed. Two weeks of absolute calm, so far as the boys could judge, during which the yacht was forced forward at her full speed capacity, which was eighteen knots. It was one day toward the end of Jack’s watch when the thing happened which was to lead them all into the jaws of disaster.

During the time that he had been on duty the boy had noticed that the engine kept slowing down. Impatient janglings from the pilot house he met as best he could with more steam. But at length even this resource failed. It was plain enough that the Valkyrie was losing speed rapidly.

Jack went over the engine with zealous care, but so far as he could see the fault did not lie there. On the contrary, every rod, crank and bolt appeared in good order. Suddenly a thought struck him. He hastened across the steel floor to the gauge on the bulkhead. What it told him caused the boy to emit a whistle of dismay.

The steam pressure had fallen to seventy-five pounds. While he watched, it dropped two pounds more, and the engine slowed down more and more perceptibly.

He threw open the door leading to the fire-room. In that black hole he saw the dim forms of the stokers on duty flitting about like gnomes in the dust-laden darkness. He hailed the nearest of them.

“What’s the trouble?”

The answer came with a grumbling rumble from the half-naked fireman as he threw open a furnace door and stood in the glare of the fire.

“S’ help me bob, kid, there ain’t more’n three tons of coal in the bunkers an’ the boss tole us to keep steam down.”

“Three tons!” echoed Jack. “How long will that run us?”

“Not h’enuff so’s you could nowtice it,” rejoined the Britisher.

“Have you any idea where we are?”

“Yus. Leastways, I ‘eard ‘em torkin’ erbout h’it ‘fore I come on watch.”

“Where are we, then?”

“H’about ten north, fifty west, I ‘eard ‘em a sayin’.”

“That’s where?” asked Jack anxiously. He knew that ten north meant somewhere pretty close to the equator. In fact, for days past he and Tom had discarded all the clothing they could dispense with, for it had grown insufferably hot in the engine-room.

“H’off the cowst h’of South Ameriky somewheres; bloaw me h’if h’I knows where,” was the vague response. “H’all h’I knows h’is that h’if we doan’t get no cowl, we doan’t get no steam.”

A quick step sounded behind Jack. As the footsteps rang out on the metal floor the boy turned swiftly. Medway confronted him.

“What you doing here?”

“Finding out how much coal we had,” responded Jack. “There’s hardly enough steam to run the engines.”

“You get back where you belong,” roared Medway, “and you, you salt-horse-eating Britisher, you get back to your work. D’ye hear me? I’ll have stuff enough down here before long to get us as far as we want to go.”

As Jack once more entered the engine-room these words stuck in his mind. “As far as we want to go.” They must, then, be nearing their destination. And what was to follow? When he awakened Tom the two had a long talk about it without coming to any definite conclusion on the matter.

One thing was positive, steam had been raised again. By what means was evident when the British stoker, who appeared inclined to be friendly, stuck his head through the bulkhead door.

“They’re a-tearing the bloomin’ ship to pieces,” he confided, and then withdrew as Medway’s step sounded on the ladder.

“How’s she workin’?” he asked briefly.

“All right,” replied Jack; “plenty of steam now.”

“Yes; and we’ll have plenty if we tear everything out of the old hooker and leave nothing but the shell,” ground out Medway fiercely.

“Gracious, Tom,” remarked Jack a few minutes later, before he turned in, “I guess they’re stripping the ship of everything that’ll burn. Hark at that?”

Above the rumble of the engines they could hear plainly through the ventilators the crashing of axes on deck, as the vandals in charge of the yacht hacked down anything that would burn, in their mad desire to reach whatever haven they were aiming for. But if the boys could have been on deck they would have perceived a strong reason for these desperate efforts to keep the yacht moving. Out of the south there was coming toward them a dread harbinger of the terror of those waters.

A sickly-looking yellow halo around the sun, a sullen heaving of the sea, which was of an odd, metallic hue, and a queer odor in the atmosphere, which was still as death,—all these signs, coupled with an alarming drop in the barometer, showed those in charge of this ominous voyage that a tropical hurricane was fast approaching, and that for the second time since the boys had come on board her the Valkyrie was in for a battle for existence.

But of all this, of course, they knew nothing. All they realized was that it was insufferably hot in their oily, murky engine-room. From time to time they were compelled to go to the funnel-shaped bottom of one of the ventilators to get even a breath of air. Medway or Hemming kept dodging up and down all day, and each time they appeared their faces were furrowed more deeply with anxiety.

It was about the middle of Tom’s watch, namely five-thirty in the afternoon, that the boy, without the slightest warning, was lifted almost off his feet by a heavy lurch of the ship. He saved himself from slipping into the revolving machinery only by clutching at an upright stanchion. At the same instant his ears were assailed by a diabolical screeching, as a wind, like the blast from a furnace mouth, was forced down the ventilators. It was an unearthly sound; a bedlam like that which might have been the fitting accompaniment of a witches’ frolic.

Jack, fast asleep on the couch, was rolled violently off it and grabbed by Tom in time to save him from tumbling into the crank-pit.

“W-w-w-what is it?” gasped the newly awakened boy, his eyes wide with amazement at the inferno of noises.

“I guess it’s a hurricane,” came Tom’s response, “and we’re running the engines on furniture!”

As he spoke, the Valkyrie appeared to be lifted skyward by a giant hand and then pushed violently down again to an abysmal depth.

“A few more of those and—good-night,” spoke Jack, whose face had grown pale as ashes.

The next few hours were filled with terror. Medway, revolver in hand, stationed himself in the fire-room, keeping the terrified stokers at work on pain of instant death. Into the furnaces of the hurricane-driven ship was piled everything aboard that would burn. Boats were ruthlessly smashed, costly mahogany and ebony trim and panelling, chairs, tables, anything, everything that was combustible.

The boys toiled as if in a nightmare. Half stunned by the violence of the vessel’s movements, sick, dizzy and aching in every limb, they kept at their tasks. But not long before midnight the end came with the suddenness of a thunder-clap. No time was left for thought even, much less preparation.

They felt the Valkyrie lifted bodily upward and then rushed downward again with appalling force. There followed a crash that seemed to be sufficient to smash the stout structure of steel and iron into a mass of junk. The boys felt themselves hurled bodily across the engine-room by some unseen force.

Then came a shout. It was Medway’s voice.

“Everyone for himself!”

The boys rushed on deck, not knowing what to expect. After that appalling crash they hardly knew if the Valkyrie was yet actually under their feet.

“Whatever has happened, this is the finish!” gasped Jack as they went.
CHAPTER IX. ASHORE.
Arrived on deck it did not take the boys long to realize what had happened. The yacht was aground, but whether on a reef of rocks or on the shore was not at first plain. Suddenly a blinding flash of lightning showed them the true situation. The Valkyrie lay with her bow ashore amidst what appeared to be a confused tangle of roots and low growing shrubs. More than this it was impossible to make out. One thing alone was clear—only too clear,—the voyage of the yacht was over. She lay canted far over to one side, making it a difficult matter to stand steadily on her sloping deck.

The crew were running about as if possessed. Any slight amount of discipline that Medway and Hemming might have exercised over them had vanished in this emergency. Some of them were actually trying to get one of the two remaining boats over the side regardless of the mountainous sea that was running. The play of the lightning was incessant. The whole sky appeared to be ablaze with livid fire. In the blue glare the figures on deck were outlined as plainly as if on the screen of a moving picture theatre. But it was grim, real-life drama that was being enacted.

The boys saw Medway and Hemming, with revolvers in their hands, go slipping and sliding across the inclined deck and rush into the midst of the group of seamen about the boat.

“drop those falls, you fools!” they heard Hemming shout above the tempest. “It’s death to launch a boat in this!”

But the panic-stricken sailors appeared not to notice the two mates. They struggled with the boat and, finally, actually succeeded in getting it overboard. Then they piled into it helter skelter. Some of them fell overboard in their eagerness, but by the glare of the lightning the boys could see that those in the boat dragged them on board again before they were sent to the bottom.

A huge wave came bearing down on them and lifted the boat high in the air. The boys uttered a shout of alarm. It looked inevitable that the boat would be smashed to bits against the yacht’s side. But those on board her managed to stave the frail craft off, and in a minute another big sea swept the little boat with her load of human beings off into the darkness beyond their ken.

Medway and Hemming stood leaning out over the bulwarks peering into the night. They were shouting something, but the boys could not hear what.

The furious wind caught their words and hurled them broadcast before they had properly left their lips.

“Is she breaking up?”

Tom shouted the words into Jack’s ear as the two boys, clinging to the shrouds, stood on the inclined deck.

“I don’t think so,” was Jack’s reply, yelled with his hands to his mouth, funnel-wise, “she’s grounded so far on shore that she’s safe for the time being, anyway.”

“We’d better go below and see how the others are getting on,” came from Tom the next minute.

In their excitement and fright the boys had utterly forgotten for the time being their companions. The thought of the plight that they might be in now recurred to them with redoubled force. Slipping along the precipitous deck they made their way to the cabin companionway. As they went they noticed the marks of the relentless axes of the crew. Except the main cabin house amidship, the yacht had been practically stripped of every bit of available timber. She looked, as indeed she was, a sorry derelict.

It is now necessary to turn back a little and discover how the prisoners in the adjoining cabin had been faring. It will be recalled that when Jack and Tom had been summarily taken from the cabin they shared with Dick Donovan, the next stateroom was occupied by Mr. Chadwick, Professor Von Dinkelspeil and Captain Sprowl.

The two weeks that had been spent by the boys in the engine-room had passed like eternity to those locked in the cabins. Of course, they had been able to communicate by means of the “Morse” tappings. But Dick’s knowledge of telegraphy was so limited that he had not been able to understand much of what was communicated to him. Nor had he been able, except after a long interval, to explain to the others that Jack and Tom had been taken from the cabin for some unknown reason connected with the machinery of the yacht.

Food had been served to the prisoners regularly, but from the sailors who brought it they had received no word of the fate of the two boys, nor could even the promise of bribes elicit a word from the men. Under the strain of their captivity and their uncertainty concerning Jack and Tom, Mr. Chadwick’s health had suffered seriously. Dick, too, had suffered from a kind of tropical fever, and lay in a semi-conscious condition in his cabin for days. This was the more unfortunate as Professor Dinkelspeil had given, through Mr. Chadwick’s telegraphy, full instructions to the young reporter concerning the movable partition.

It had been agreed by the prisoners that Dick should remove the partition and get into the next cabin. There was a chance that the door would be open, in which case Dick might make his way into the main cabin and unlock their door in which they knew the key was kept. What they would do after this was not arranged; but they all felt that if they could get out they might find some way of bettering their situation.

Dick’s illness interfered with these plans; but the night that the storm broke he had forced himself to rise from his bunk, and despite his weakness he determined to try to remove the partition separating him from the next room. It was in panels, as he knew, and with the aid of his knife, which, luckily, the men in possession of the yacht had not thought worth taking from him, he succeeded in removing the screws that held one of the panels in place.

He lifted the panel out and found himself looking into the next cabin.

It was brilliantly lighted and, to his astonishment, the walls were lined with racks in which were rifles and pistols. It was, in fact, Medway’s cabin, to which he had removed the yacht’s armory so as to have it out of the way of any of the crew who might take it into their heads to form a second mutiny.

While the yacht rolled and plunged in the hurricane, Dick climbed through the hole made by removing the panel. Once in the cabin he stood stock still, undetermined what to do. After a minute’s reflection he decided to see if the door would open. But he had hardly taken a step with this intention in view when the door was flung violently open and Hemming stood before him.

For one instant both stood perfectly still. Dick’s knees shook under him. Even in his usual health he would have been no match for the burly Hemming, but as it was he felt incapable of putting up even the most feeble resistance.

“You young imp of Satan, what are you doing in here?” bellowed Hemming, with a snarl like an angry tiger.

He raised his fist and sprang forward. Dick, more by instinct than anything else, seized one of the pistols hanging on the wall. Hemming paused as the boy leveled the weapon at him. But the next instant he sprang forward as if to fell the boy to the ground. Dick jumped back to avoid a heavy blow and his finger involuntarily pressed the trigger.

A click resulted, but there was no explosion.

The weapon was unloaded. With a shout of triumph Hemming rushed him, but just as his hands were on Dick’s throat there came a stunning crash that hurled them both to the floor.

When Dick, who had rolled under a bunk with the force of the upheaval, regained his feet, he was alone in the cabin. Dazed and half stunned, he stood still trying to collect his thoughts. Suddenly there came a mighty pounding on the wall of the cabin he had just left. This was accompanied by muffled shouts.

“Help!” was what Dick made out above the uproar about him.

He rushed to the door which Hemming had left open behind him. The lights in the main cabin were still on and showed him that the lower part of the place was awash with water. He had hardly time to realize this discovery when the lights went out and the place was plunged in total darkness.
CHAPTER X. THE CASTAWAYS.
Dick had a mind that worked quickly. It did not take him long to arrive at an approximately correct idea of what had happened. The yacht was ashore; and the water lapping about the lower part of the cabin showed that she had stove a hole in her bottom or else strained her plates so badly that the water was rushing in.

Suddenly the frantic pounding on the wall of the cabin which held Mr. Chadwick and his fellow prisoners recommenced. The shouting, too, was now plainly audible, for above the door opening into the main cabin was a small grating for purposes of ventilation.

“Help! help! The cabin is half full of water,” cried the imprisoned men.

“Gracious! They’ll drown if I don’t do something and do it quickly!” flashed through Dick’s mind.

All at once he felt his feet grow wet; the water already had reached half way up the steeply inclined cabin floor. There was not a minute to lose. He started for the cabin door, hoping to find a key in the outside of it, when footsteps sounded on the companionway stairs.

“Who’s there?” he yelled.

The response that came back through the darkness caused his heart to give a bound of delight.

“Jack Chadwick and Tom Jesson. That you, Dick?”

“Yes, yes, yes! Hurry up, fellows! Your dad and the rest of them are in that cabin, Jack, and the place is awash. The water’s gaining every minute.”

The boys groped their way to his side in a jiffy. There was no time for greetings just then. The three lads rushed for the door of the cabin in which Jack’s father and the others were imprisoned. But a shock awaited them. There was no key in the outside of the door. Nor did it yield to Jack’s furious poundings.

“Dad! dad! are you all right?” cried the boy.

“Thank Heaven it’s you, Jack!” came from within. “Get this door open somehow, will you? The water in here is rising all the time.”

“Yes,—yes,” responded Jack, feeling about desperately for some means of opening that door.

While he did so, the three boys were almost thrown off their feet by the sudden settling of the yacht as she subsided more deeply into the land which she had struck.

In the darkness some object came rolling across the cabin floor. It struck Jack’s knees, inflicting a painful blow. But the boy gave a simultaneous exclamation of delight.

“Hurrah! Here’s just the thing!” he cried, “one of the cabin chairs. They must have unscrewed it to feed the furnaces with.”

He stooped and picked it up.

“Stand back from the door inside there!” he shouted as he swung it over his head and brought it smashingly against the wood. Again and again his strong arms brought the heavy iron support of the swivel chair against the cabin door. At the fourth stroke the wood splintered, and in a few seconds the door was fairly burst from its hinges and three men rushed out from within, followed by a gush of water. The break in the yacht’s side had occurred in the plates outside the cabin in which Mr. Chadwick and his companions were confined. When Jack released them the water had already risen above the lower berth and was pouring in in an ever increasing stream. Fifteen minutes later and the boys might have been too late.

It was no time for explanations. The cabin floor was more steeply inclined than ever since the fresh subsidence of the stranded craft, and they made for the companionway stairs. As they reached the deck, Jack noticed that even in the brief space of time that they had been below, the wind had perceptibly decreased in violence.

But the lightning still played vividly, and in its glare they saw two figures advancing toward them. They were Medway and Hemming. Both had revolvers in their hands.

“Get back down below!” shouted Medway, as he drew near.

“But the whole place is awash!” cried Jack indignantly. “The deck is the only safe place.”

“I don’t care. You get below or——”

A sailor, one of the few left on board since the dereliction of the rest of the crew, approached Medway, and pulling his arm to attract attention, said something to him.

“Keep back there, you,” cried Medway with a threatening flourish of his pistol.

Then he and Hemming turned and followed the sailor to the stern of the boat. The group of rescued prisoners remained where they were. In the mood Medway was in, it didn’t appear safe to interfere with his wishes, and as they could not have bettered their condition by following the man, they made no move to do so.

While they stood there, talking in low tones and discussing their perilous situation, the storm perceptibly weakened in force. Like most tropical hurricanes it had spent its fury in a few hours and was now sweeping north, having inflicted irreparable damage to the once staunch yacht. In another hour’s time the wind had died down to a stiff breeze, and the sea was no longer raging as it had when the Valkyrie struck.

“I vunder vot has become of dot feller Medvay?” said the professor presently. “Ach! dot rascal, he has broken my beautiful yachts und ruined mein expedition.”

“It is odd that he doesn’t show up,” said Mr. Chadwick.

“I haven’t noticed anyone about for some time,” declared Tom. “I wonder what has become of him. Maybe he is up to some fresh mischief.”

“Dunno as there’s much more the pesky varmit kin do,” commented Captain Sprowl, a down-easter from Maine, and the veteran of many tempestuous voyages. “Consarn him,” he went on angrily, “he’d look uncommon well decorating the end of a yard arm, according to my way of thinking.”

“I know a few that ought to keep him company,” declared Jack, the way in which they had been treated rankling within him. “Tell you what,” he continued presently, “I’m going to have a look about the deck.”

“Be careful,” warned his father, “those rascals are capable of any mischief.”

“As if Tom and I didn’t know that!” responded Jack. “But I’ll be on the lookout, dad. Don’t worry. Come on, Tom.”

The two boys made off into the darkness which was now illumined only by an occasional fitful flash from the departing storm. It was some little time before they returned. When they did the news they brought gave the little party a galvanic shock.

“They’ve gone! Deserted! Left us cold!” cried Tom.

“What!” cried his uncle.

“That’s right,” confirmed Jack. “The stern boat, the only one that was left, is missing from the davits. They must have waited for the sea to go down and then made off, leaving us to our fate.”

“Wa’al, cuss their blue-nosed pelts!” roared Captain Sprowl. “I’d give all I have to get my hands on ‘em for jus’ erbout ten seconds.”

But neither the captain’s righteous wrath nor the just indignation of the rest of the deserted party could disguise the fact that they were left, boatless and marooned on a craft leaking like a sieve, castaways on an unknown coast.
CHAPTER XI. ABOARD THE WRECK.
The morning dawned as only a perfect tropic morning can. The sea was as smooth as glass. Not a cloud was to be seen as a reminder of the elemental fury of the preceding night. The sun, as it rose, a huge red ball above the rim of the sea, showed them some things about their situation that were calculated to give them good cause for worry.

In the first place, it must be said that there was not a sign of the two boats to be seen. For anything that appeared of them, they might never have existed. Indeed, on that calm, serene dawn the fantastic events of the wild night that lay behind them did seem very much like the distorted experiences of a nightmare. But their haggard, anxious faces, and the pitiable condition of the Valkyrie, bore eloquent testimony to the fact that all that had passed was only too true.

As a matter of fact, the night’s incidents proved to be only minor matters for consideration in view of one greater fact that now confronted them. The Valkyrie lay with her bow well up amidst a tangled mass of low-growing jungle. Her stern, from just forward of midships, was almost under water. Even a casual inspection showed that if the sea should rise again it was not all unlikely that she might slide off into deep water and sink.

But the most astonishing thing about this land which they had struck was that they could see across it and to either of its limitations. It was, in fact, an island, stranded there out of sight of all other land. In shape it might have been likened to a splash of gravy on a plate, so irregular in form was it. As to dimensions, it was probably a quarter of a mile across, and perhaps twice that in length.

“This explains something that has been puzzling me,” exclaimed Mr. Chadwick, as they made this discovery. “It’s plain enough now that the crew knew there was no land to be expected in this part of the ocean, and when we struck they at once assumed that we had encountered some uncharted rock and so took to the boats.”

This explanation threw some light on the desertion of the yacht by means of the boats, for it had occurred to all of them that if the yacht had struck on the coast of the mainland there would not have been such a precipitate rush to leave her.

“My idea is to look in the pilot house and overhaul the charts,” said Captain Sprowl, after some discussion had ensued as to the best course to follow. “Our course must be marked till noon yesterday, anyhow, and we can find out about where we are.”

Whatever may have been Medway’s other faults, he could not have been called a slovenly navigator. The course of the yacht was plainly marked up till eight bells of the day preceding, and showed that they were then off the coast of Brazil. Captain Sprowl “overhauled” the pilot house some more, and at noon made an observation with a sextant he had unearthed. After making some calculations, the results of which were awaited with an eagerness that may be imagined, he announced that the position of the yacht was about one hundred and fifty miles from shore, and a little to the south of the mouth of the Amazon River.

“Himmel,” cried Professor Von Dinkelspeil, his frog-like eyes gleaming through a huge pair of horn-rimmed spectacles, “dey vos bringing us rightd vere I vanted to go!”

“Yes,” said Mr. Chadwick, “the professor’s destination was the Amazon River, but I must await his leave before telling you what his exact object was in coming to this part of the world.”

“Treasure, wasn’t it?” hazarded Dick Donovan.

“I’m afraid you have a reporter’s love of the picturesque,” smiled Mr. Chadwick. “Yet I suppose it was treasure of a kind; but not of the sort that the misguided crew imagined.”

“It’s this pesky island that puzzles me,” grunted Captain Sprowl, bending over the chart and knitting his brows. “There isn’t anything like it marked here, and this chart is based on the very latest survey made by the British cruiser, Charybdis.”

“Maybe it was too small to mark down,” suggested Jack.

“That shows all you know about navigation, my boy,” rejoined the blunt old sailor. “An island like this, stuck right bang out in the track of ships, wouldn’t be left uncharted.”

“And yet it was solid enough to knock a hole in us,” said Tom. “It must have been here right along.”

Captain Sprowl’s rejoinder was an astonishing one.

“Now d’ye know, I ain’t so all-fired sure of that,” said he.

“You think it is of volcanic origin?” asked Mr. Chadwick.

“No sir-ee, not by a jugful. You see, we are somewhere’s off the mouth of the Amazon River. A bit to the south maybe, but the drift sets south. Did you ever hear of the floating islands of the Amazon?”

“Yes,” rejoined Mr. Chadwick, while the others said nothing, “but I always thought that they were more or less of a myth.”

“Not so’s you could notice it,” was the reply. “I’ve heard tell of bigger ones than this. They get detached from the upper reaches of the river during floods and are carried out to sea. They’ve been met with much further out than this, and a dern sight bigger, too. They’re perfectly good islands, they say, except for one thing.”

“What’s that?” asked Jack, for the captain had paused as if he expected someone to put a question.

“Why, they’ve got a mighty oncomfortable habit of sinking. You see, they ain’t much more than a sort of big door mat held together by twisted roots and so forth, and when they get good and soaked through—down they go.”

“Blitzen! Den you dink dot dis island may go py der bottom?” gasped the little professor.

“Wa-al, it wouldn’t surprise me,” rejoined the captain, producing a pipe and filling it leisurely. When it was lit and drawing, he supplemented this remark:

“We’ve got to get ashore, gents.”

“That’s plain enough,” said Mr. Chadwick, “but unless some ship picks us up, how are we going to do it?”

“Why, as I onderstand, these boys here have a sort of fly-with-me-swim-with-me boat, ain’t they?” asked the captain. “What’s the matter with our using that?”

It was odd, and goes to show how confused the average human mind may become in a big emergency, but up to that moment not one of them had thought of the Wondership. Her awkward bulk was still secured on the top of the midship cabin house, and as far as could be seen she was undamaged.

“But the rent in the gas bag?” objected Mr. Chadwick.

“I guess we can fix that,” volunteered Jack. “Some canvas and pitch will make a patch that will hold.”

“Plenty of those aboard,” said the captain. “Now, I tell you what we’ll do. We didn’t have much of a breakfast, and we’re all as empty as a whale that ain’t struck no fish. Hungry folks can’t do good work. Give me a crew with full stomachs and I’ll take a lumber raft across the ocean. I’ll turn to with Dick here, and cook up a good meal. The boys kin overhaul their Johnny-jump-up, yonder, and the professor and Mr. Chadwick can get to work selecting supplies and so on to stock the thing with. For we may land, if we land at all, in some place where they ain’t got no hotels to welcome shipwrecked strangers.”

The captain’s suggestions met with unanimous approval, and while Jack and Tom clambered up to inspect the Wondership, the others scattered on their various tasks. As they worked, Jack and Tom from time to time took a look at the island on which the yacht rested. It might have been that their imaginations were quickened by what the captain had said, but it appeared to them that the bushes at the water’s edge were gradually subsiding into the sea.

If this actually were the case, there was need for quick work, for the floating island was all that was keeping the Valkyrie above water. If, as the captain feared, the island subsided, the yacht would go with it to the bottom beyond the shadow of a doubt.
CHAPTER XII. IN DIRE PERIL.
It was mid-afternoon by the time that the ripped bag had been patched with canvas, carefully sewn with stout waxed thread and then pitched with a resinous mixture compounded by the captain. By this time, too, the lockers had been filled with provisions from the yacht’s pantry, many of them in concentrated form especially selected by the professor for his projected expedition, the object of which still remained a mystery.

When this had been done, there was nothing left to be accomplished but the launching of the Wondership. The sea remained smooth, but without question the island was sinking rapidly. This made the need for haste imperative. Yet Captain Sprowl allowed nothing to be slighted. Maps of the district where they expected to land, navigating instruments and the ship’s chronometers were placed on board. The professor’s papers were found to have been stolen from his cabin, which had been ransacked from floor to roof; but, luckily, his most important documents he carried on his person.

As for clothes, they could take only what they had on; for when the work of loading was complete, the Wondership carried a pretty heavy cargo, besides the six persons who were to travel in her. This number, too, was augmented by a seventh in the person of Judkins. Feeble groans from his cabin had led to the discovery that the injured man had been left behind by his companions. He was carried out and placed in the machine before it was launched so as to lose no time later in hoisting his helpless form over the side.

The tackles by which the craft had been hauled on board luckily remained intact, and by passing the ropes around a hand winch they found that they could hoist her into the air and drop her gently upon the water. The list of the ship aided the transfer materially, and the work of immediate preparation for their adventurous trip occupied but a small portion of an hour.

When all was in readiness and the Wondership floated alongside, they descended by the companionway, and a few minutes later the engine was started. As they glided off to the westward, they noticed that the island was almost awash. Before they had gone five miles, nothing was visible but the masts of the yacht and her yellow funnel. Within ten minutes more these, too, had vanished, and they knew that the Valkyrie had ended her last cruise. They were alone on the ocean.

Their plan was to keep on a due westerly course, which would bring them in time to land, without fail. Once landed, the proposal was for a part of the castaways to strike off and seek out a town or village where aid might be procured. Aside from this, their plans had been left to such circumstances as might confront them on the Brazilian shore.

The bulky machine did not draw as much water as might have been anticipated, owing to its broad displacement and the lightness of the metal of which it was built. In fact, under different circumstances, the voyagers would have enjoyed the novel experience. Except for the hum of the propeller at the fore-end of the craft she moved noiselessly through the water. All vibration and jar were absent, and the motion could only be compared to that of some gracefully gliding water bird.

“What speed are we makin’?” asked Captain Sprowl, who was leaning back in his cushioned seat smoking luxuriously like a magnate in his motor car.

“About twenty miles an hour,” was Jack’s reply after a glance at the speed-registering device, which formed one of numerous dials and instruments attached to the dash-board. As Tom had once remarked, the dash-board of the Wondership looked “like the bridge of a battleship,” what with its compasses, registers and meters of various kinds.

“That ought to bring us in sight of shore before very long,” commented the captain, “I’d like to land before dark. This coast ain’t very thickly inhabited, so far as I know, and them as do live there may not have a very hearty ‘welcome’ on their door mat for us.”

“We’ve got plenty of rifles and ammunition,” declared Tom boldly, “in case anyone attacks us.”

“A good way to keep out of trouble, son, is not to go lookin’ for it,” was the captain’s response, “and anyhow, what good ‘ud your rifles be in a thick forest of trees with some sort of a savage behind each of ‘em?”

Tom looked abashed and said nothing. But Dick struck in with a question.

“There are savages ashore, then?” he asked.

“Wa’al, I ain’t sayin’ no and I ain’t sayin’ yes,” said the captain evasively; “but Brazil is full of river Indians, and at certain times of the year they come down to the coast to get turtles’ eggs and fish and so forth; and I’ve got a notion in the back of my head that they ain’t just as gentle and refined as they ought to be, ‘specially where they see a chance to get a little loot.”

Nothing more was said for some time, and the Wondership forged smoothly and steadily ahead. Suddenly the captain, who had been looking over the side, drew their attention to the water.

“Look down there,” he said, “if you boys want to see a rare sight.”

They all peered over and saw, swimming slowly along in the translucent water, a large, whitish-colored fish with a huge protuberance of some kind sticking out from its head.

“By the plunging porpoises of Portugal,” exclaimed Dick Donovan, “what under the sun is it?”

“A sword-fish?” hazarded Jack.

“That’s right, lad, and an old slapper, too. My! That sword of his must be five feet long if it’s an inch. Look at the spikes sticking out from it!”

“Jimminy! I’d hate to get rammed by that,” cried Tom, gazing down at the great fish with its odd, bony sword.

“Gracious! If he ever took it into his head to attack us, he’d soon make a hole in the bottom,” cried Jack the next moment, as the sword-fish gave a quick twist of its tail and darted ahead.

“Plenty of cases have been known of sword-fish attacking ships,” declared the captain. “In 1894, the whale ship Mary Ambree came into New Bedford with a big sword from a sword-fish stuck into her port quarter. It had broken off and was rammed about six inches into the wood. The fish that owned it must have died on the voyage up and rotted from its weapon.”

“That’s a peril we didn’t count on,” said Mr. Chadwick. “It would be a mighty serious matter for us all if that fish was to ram us, either by intent or mistake.”

“Maybe so vee bedder go py de air up,” said the professor, a trifle nervously.

“It might be a good time to test that patch, anyhow,” declared Jack.

He turned on the gas inlet, and with a rush and hiss the bag began to fill. But he shut it off before sufficient buoyancy was obtained to lift them. He did not wish to waste gas unnecessarily, for although an extra supply of the gas-making material was on board, still there was not any too much of it.

The patch appeared to hold perfectly. So interested were they all in seeing if this vital part of the craft was to prove efficient, that none of them paid any attention to what was going on about them.

It was Dick Donovan who excitedly called their attention at length to a great commotion on the water ahead of them. The sea was boiling up almost as if a volcano had suddenly opened beneath it. Then from the midst of the confusion, a great spout of water shot heavenward as if it had been projected from some mighty fountain.

“It’s a whale!” shouted Captain Sprowl, who had served his time in the “fishery,” as it is called.

“Himmel! So idt is!” cried the German naturalist. “Ach! A big vun, too! Blitzen, see him!”

As he uttered these excited cries the whale leaped from the water,—“breached,” as it is called by whale-men. High into the air the huge form, fully eighty feet in length, rose much as though the colossal fish were imitating a leaping salmon. As it settled back with a mighty crash that sounded like the report of a cannon, a second and much smaller whale leaped from the water.

“It’s an old whale and her calf!” shouted the captain. “Oh! if I had a harpoon!”

“Poys, dot is a sight vot iss not possible to be seen efery day,” exclaimed the professor enthusiastically.

“Well, I hope they don’t decide to investigate us,” spoke Dick Donovan, “I’d as soon have the Flatiron Building coming alongside.”

“They’d make mincemeat of us sure enough,” declared the captain, “but I guess they won’t make trouble for us. It’s mostly the old bulls that attack boats. Cows is peaceable enough if you leave ‘em alone.”

“Be very sure that we’ll leave her ladyship yonder alone,” laughed Mr. Chadwick.

As he spoke there was a sudden swirl in the water ahead of them where the two whales were swimming side by side, the young one close to its mother. Then came a smother of foam and then the water alongside the swimming mammoth was dyed crimson.

“It’s the sword-fish!” cried Mr. Chadwick. “He’s attacked the whale!”

“No, it’s the calf he’s after!” shouted the captain. “Hail Columbia! Now look out fer squalls!”

“Say!” cried Tom, “we’d better get away from here. Look, the big whale is turning on the sword-fish! There’ll be some waves here in a jiffy that will swamp us, if we don’t look out.”

“That’s right,” agreed the captain, “get this craft up in the air if you can, Jack. There’s nothing worse on land or sea than an old cow whale whose calf has been injured.”

As he spoke, the big whale rushed at the sword-fish whose ivory weapon had impaled her young one. Her great flukes struck the water with resounding crashes, making waves that threatened to swamp their craft.

“Get up! Get up!” roared Tom. “We’ll be swamped!”

Jack turned on the gas full power, but the ship did not rise. Her heavy load made her sluggish.

“Start her!” bellowed the captain. “Start her for your life!”

“I can’t! She won’t rise!” cried Jack despairingly.

“Then we are lost. Look there!”

Coming toward them at the speed of an express train was the huge whale. On she drove, making straight for the stranded motor ship.

“She’s going to attack us! She thinks that we killed her young one!” cried Mr. Chadwick.

The motor ship lay straight in the path of the maddened whale. As they regarded the fury of the oncoming creature with apprehensive eyes, they could almost feel the terrible impact and the struggle for life that must ensue when the leviathan struck their frail craft.
CHAPTER XIII. ATTACKED BY A WHALE.
On came the whale. She was a huge, humpbacked monster, with a gigantic square head that looked as solid as the prow of a battleship. Every instant appeared to increase the speed at which she traveled. Fascinated by terror they could not take their eyes off the onrushing peril,—with the exception, that is, of Jack.

The boy was struggling with an auxiliary valve for gas supply which had been installed with the idea of quick-filling the bag. But the ordinary valve had worked so well alone that the auxiliary had not been used, and it was jammed and corroded.

“Hurry! hurry!” shouted Tom. “She’ll ram us in another second!”

But still the ship would not rise. The bag was swelling every instant, though, and it seemed that if they were granted only a molecule more of time there might be a possibility of rising before the whale struck them.

Among other things, the Wondership had been provided with conveniently placed life preservers. Jack now shouted to the others to put these on.

“When she hits, jump outwards!” he yelled.

They began to adjust the life saving contrivances, which laced on like jackets. But before they had them half ready the whale was within a few feet of the craft. Such was her speed that in front of her there was a mighty mass of blue water piled up. Her blunt, square forehead had raised the billow just as a round-bowed ship will “push the river in front of it,” to use a graphic sailor phrase.

And now an astonishing thing happened. The wave struck the frail motor ship a few seconds before the impact of the whale’s head. The great sea gave the craft just the impetus that was required. Buoyed up by the inflated gas-bag the wonder craft rose into the air as the wave rolled under her, and hung suspended in that element for some minutes. She did not rise far above the water, but the five or six feet that she reached was sufficient to clear the onrushing whale.

As the huge, humped back with its ugly rough hide passed under them Captain Sprowl picked up a rifle and pumped an unmerciful stream of lead into the monster.

Instantly she spouted, and the boys and their companions found themselves in the midst of a downpour of water and vapor. But the main danger had almost miraculously been avoided. As the Wondership settled down to the water once more, the whale could be seen rushing blindly on. A cheer went up from the boys.

“That’s the time we fooled her!” cried Tom exultantly.

But Captain Sprowl urged Jack to get the bag fully inflated as quickly as possible.

“She’ll be back afore long,” he prophesied. “She’s as mad as Pharaoh’s sow right now, and she won’t give up as easy as all that.”

Sure enough, in a few minutes the mound of water that marked the whale’s progress could be seen returning toward them at the same rapid speed. But by this time, Jack had secured a wrench and had managed to turn the stubborn auxiliary valve. As the whale neared them, he set the rising planes and started up the propeller.

The motor craft hesitated, and then like a wind-driven leaf she shot upward. It was not an instant too soon. As her rudder rose drippingly from the sea, the whale rushed viciously under her. Another fraction of a second and there would have been a different ending to this story.

“Saved, by the great horn spoon!” roared out Captain Sprowl. “Lad, that gas-meter thing of yours worked just in time.”

“It certainly did,” agreed Jack, ordering Tom to set the rising planes at a sharper angle.

“Look!” shouted Tom suddenly as they shot upward, soaring above the smooth surface of the ocean. “The sword-fish is going to attack the whale herself, now.”

They saw, far below them, the sword-fish’s ivory blade, stained red from its attack on the baby whale, rushing at the old cow. She gave battle bravely. In an instant the waters were lashed into such a fury that they could see nothing of the details of the battle.

But Professor Von Dinkelspeil, who had brought his binoculars with him from the wreck, determined, in the interests of science, to see all he could of the battle. He leaned far over the side.

“Ach! vot a sight! I nezzer saw such a dings!” he cried. “Oh! I vish I hadt a camera!”

“I’ve got mine,” cried Dick. “I’ll take a picture!”

The red-headed young journalist leaned out over the edge of the Wondership and tried to get a focus on the furious battle beneath.

“Look out, you’ll overbalance!” called Tom.

But the good advice came too late.

Without the slightest warning to give them a chance to save him, Dick Donovan’s body pitched over the side of the craft and fell like a stone downward through space.

For an instant the shock of the occurrence held them all spellbound. Then they woke into action with a series of shouts and cries that made inextricable confusion.

“Send us down! Send us down!” cried Mr. Chadwick.

“I daren’t,” declared Jack, “those creatures would certainly ram us.”

“Quick! Help him!” cried Tom, who had been leaning over watching the spot where Dick had vanished. It was not far from the place where the two monsters of the sea were battling, some two hundred feet beneath the flying ship.

Jack’s face was pale, but his manner was determined as he shut off the engine and ordered Tom to get out the grapnel rope. This was a rope some five hundred feet in length, of light but exceedingly strong fiber. At its end was a grapnel, a sort of four-forked anchor. The idea of it was to anchor the Wondership in case of a high wind or other emergency.

Tom produced the rope and Jack flung off his garments down to his underclothes. While he did this Tom had, in obedience to his chum’s orders, made the rope fast to an interior stanchion of the ship.

“See if you can spot him,” Jack said to Tom when the rope had been made fast.

“Yes! Yes! I see him!” cried Tom excitedly, as he looked over the side. “The life-jacket is floating him but he looks half drowned. He can’t strike out to save himself.”

“The fall must have stunned him,” cried Mr. Chadwick; “it’s a good thing he had that life-jacket on!”

Jack began climbing over the side, holding on to the rope that now dangled from the floating air craft.

“What are you going to do?” demanded Tom, who up to this moment had imagined that Jack meant to catch Dick by the grapnel.

“I’m going down after Dick,” was the quiet response as the boy shot down the rope toward the sea beneath. “Keep an eye on that rope, Tom, and haul up when I tell you!”

“Ach! dey vill both be killed!” cried the professor frenziedly. “Dis iss madtness!”

But Jack Chadwick was not a boy who did things without having first figured them out. As he slid down the rope he knew just what he meant to do when he touched the water.

In the meantime Dick’s body, buoyed up by the life-belt he had so luckily neglected to remove, was floating on the surface. About an hundred feet off, the whale and the sword-fish were battling furiously.

In mid-air the Wondership hung suspended, her white-faced, frightened passengers peering over the side, while between the air-buoyed craft and the sea Jack Chadwick’s body swung on the thin rope like a pendulum.
CHAPTER XIV.  THE SEA-COW’S LULLABY.
It was an anxious moment, or rather succession of moments, for those in the Wondership. Luckily there was but little air stirring, and that little was blowing from a direction which brought the big craft down over the floating boy.

Jack watched his opportunity like a mousing cat. As the grapnel in which he was standing, holding with one hand to the rope, swung above Dick, he leaned out and with a swift, sure grasp drew the lad up. They saw him disengage the life-jacket from the unconscious young reporter and envelop his own body in it.
He leaned out and with a swift, sure grasp drew the lad up.—Page 144.

This done, he deliberately secured Dick to the grapnel by looping the rope around the boy’s body and fastening it with one of the forked ends. Then he slipped off into the water and shouted to Tom, to “call all hands” to haul Dick up to safety.

“But what about you?” cried Tom in an agony of distress.

“I’ll get along till you lower the rope again. Haul up now and be quick!”

There was nothing to be done but to obey the gritty lad’s order. Inch by inch they hauled on the rope till at last Dick could be reached and pulled on board. No time was then lost in lowering the rope to Jack. It was not any too soon. Attracted no doubt by the furious flurry of the battle between the whale and the sword-fish, several fish with triangular fins were to be seen cruising about in the vicinity.

“Sharks!” cried Captain Sprowl; but it hardly needed his warning cry to apprise the boys of the nature of this new peril.

Fortunately, Jack kept his head and made a prodigious splashing in the water whenever a fin came close. This had the effect of scaring off the sharks for the time being, although had Jack delayed an instant in grasping the rope, securing himself, and giving the word to haul up quickly, there is little doubt that they would have rushed at him en masse and made escape impossible. As it was, Captain Sprowl had his rifle ready to shoot the first one that drew near the boy, but luckily there was no need of his shooting.

By the time the sharks had rallied from their temporary alarm Jack was being hoisted upward, and within a few minutes was once more on board. Congratulations on his daring act were loud and hearty and, as may be imagined, when Dick came to himself his thanks were not rendered the less sincere by the knowledge that the plucky young inventor had risked his life to save him.

When all was in readiness the engine was set in motion once more, and the machine shot ahead still on a due westerly course. Before long there was visible, on the western horizon, a dim blue line that at first looked like a bank of low-lying clouds.

It was Tom who first proclaimed it for what it was:

“Land ho!” he sung out in nautical fashion, and a ringing cheer was the response.

“What part of the country is it, I wonder?” exclaimed Jack. “I hope we will land near a town or settlement of some sort.”

Captain Sprowl looked dubious.

“Hard telling what we’ll strike,” he said, “but we’d best be prepared not to find any hotels or tably de hoteys around, unless the ‘gators and sea-cows have started one since I was on this coast last.”

“Ever here before?” asked Dick, who by this time had fully recovered.

“Shipwrecked off this coast in the Mary Anne McKim of Baltimore in ‘86,” was the brief reply.

As they drew nearer to land they saw that the coast which faced them was apparently well-wooded. The towering forms of palms and other large trees could be made out some time before any other details were distinguishable.

On closer view, however, they saw that the country was undulating and hilly. A long line of dense forest rose, seemingly, directly from the water. It stretched north and south as far as the eye could reach. It was, in fact, the great primeval forest that clothes this part of South America from the seacoast to the foothills of the Andes, two thousand miles to the west.

“Just as I thought,” grunted Captain Sprowl, laying aside the binoculars with which he had been scrutinizing the coast; “it’s a limber-go-shiftless sort of a place; but at any rate it’s better than nothing. It’s dry land, anyhow.”

They all concurred in this view. It was something to look forward to after their buffeting at the hands of the ocean,—this prospect of setting foot on what the captain called “terrier firmer” once more.

As the Wondership winged its way closer to the coast, Jack began to look about for a place to land. At first sight there was none visible. The massive dark crowns of shady mangoes, the towering forms of the palms and certain stately dome-like and somber trees, shot up everywhere above the surrounding forest, which grew as densely as weeds in a neglected pasture.

On a white strip of beach the surf hurled itself thunderously, spuming and foaming up to the very roots of the trees.

“Doesn’t look very promising for a landing,” remarked Tom, gazing about quite as anxiously as Jack for a landing place.

“I should say not,” was the reply of the boy at the steering wheel.

“Maybe the woods will open out more when we get over them,” rejoined Tom.

“I hope so.”

“Can’t we land on the beach?” asked Mr. Chadwick.

“Not a chance,” rejoined Jack. “I wouldn’t dare to come down on that tiny strip of sand. A slight miscalculation would put us in the surf. The ship would be ruined and we might be drowned.”

“Well, as the poet said, ‘all as goes up must come down,’” remarked the captain sententiously, “so I s’pose we’ll find some place to drop.”

“No bird ever flew so high it didn’t have to light,” put in Dick whimsically, whereat they all had a laugh.

“Well, at all events, it looks as if we were destined to have the place to ourselves,” remarked Mr. Chadwick.

“I wouldn’t be too sure,” responded Captain Sprowl, pessimistically.

For some reason or other the old mariner did not look entirely at ease. He scanned the tree-grown coast anxiously with his binoculars.

They were just about over the crashing surf when above its roar a most peculiar sound fell upon their ears.

It came swelling over the woods and was startlingly like the cry of someone shouting out in agony.

“What in the name of time is that?” cried Tom, turning a rather alarmed face on the others.

“Indians!” shouted Dick. “We’d better steer clear of here.”

“Idt vos somevuns in pain,” declared the German savant nervously.

Again came the cry. A long shuddering wail that fairly made their flesh creep. They no longer tried to disguise their alarm, but exchanged disquieted looks.

“It is someone suffering pain,” declared Mr. Chadwick. “Better look to your rifles, boys.”

But Captain Sprowl held up his hand to command silence. The grizzled old sailor listened intently for a minute. He was waiting for a repetition of the cry that had so disturbed them.

All at once it came once more,—a moaning, long-drawn sigh this time. It was like the cry of a suffering sinner on his death-bed.

“It’s an awful sound!” shuddered Tom nervously.

“Awful, but blamed human,” put in Captain Sprowl with a sigh of relief, like a gust of wind. “That’s nothin’ more alarmin’ than a sea-cow singin’ her evenin’ song.”
CHAPTER XV. THE PROFESSOR IN TROUBLE.
“Dancing dairy farms of Delaware!” gasped Dick. “What on earth is a sea-cow?”

“Gives salt-water milk, I guess,” grinned Tom, greatly relieved, however, to find that the blood-curdling noise was of animal and not human origin.

“That shows that you young chaps have a heap to learn,” chuckled Captain Sprowl. “The sea-cow don’t look no more like a cow than I do.”

“Ach, no! Der zee-cow iss der manatee,” put in the professor.

“That’s right, professor, and I guess we ain’t the first that’s been scared by their unholy howlings,” said the captain.

“Idt pelongs py der family Manitid?,” went on the professor, “undt is vun of der Herbiverous Cetacea.”

“In plain United States, it’s a sort of grass-eating fish,” explained the captain, “although it looks something like a big, clumsy seal. There must be a river some place about here, for they always live near the mouth of streams. I’ve seen ’em twenty feet long; but, in general, they run about twelve feet. Had one upset a canoe under me in Florida once; but there ain’t many left there now.”

“A river!” exclaimed Jack. “Well, then, that unearthly racket means that we’ve found a place to land on, for a river will do just as well as dry land so far as we are concerned.”

“By the holy poker! You’re right, lad,” declared the captain; “bear off a few points to the north there. That’s where that sea-going dairy ranch is located, to judge by the racket.”

Jack swung the air craft, as she now was, in the direction indicated. They flew above the densely growing tree tops for a short distance, and then they suddenly found themselves above the estuary of a fair-sized river. Sand-bars and small, marshy islands lay in every direction in the delta, and as the shadow of the Wondership fell upon the land below, numerous large, dark-colored animals, looking like gigantic slugs, slipped off into the water with alarmed grunts and cries.

“There’s your sea-cows,” said the captain, waving an explanatory hand downward toward the vanishing forms.

Jack swung the Wondership in a long semi-circle, and then began to glide earthwards. The descending planes were set and the ship shot downward with great rapidity. They all clung on tightly, and in a few minutes, with a mighty splash, the Wondership was resting on the surface of the river, hemmed in by the dark tangle of jungle that grew down to the water’s edge on both sides. They could see the river winding its way seaward for some distance till a bend hid its further course.

On the bar outside the surf thundered and roared unceasingly. But on the shadowy river all was silent as a country graveyard. A moist, steamy atmosphere enveloped them, strongly impregnated with the smell of rank vegetation and rotting timber.

The sun was getting low, and in the shadow of the great trees it was already twilight.

As the Wondership alighted, Jack was compelled to start the propeller once more, for the current ran so swiftly that otherwise the craft would have been borne down stream upon one of the sandy islets from which the sea-cows had vanished.

The whirr of the great screw sounded oddly amidst the solemn hush of the evening, and the Wondership began to forge ahead. It glided slowly up stream against the muddy-colored torrent that was sweeping down. The travelers’ eyes were busy in the meantime, taking in every detail of the strange scene into which they had, literally, dropped.

All at once the craft rose as though lifted from beneath and lurched so that Tom, who was standing up, was almost thrown out.

“Goodness! What’s that, an earthquake?” he gasped, gripping one of the stanchions that supported the gas-bag part of the craft.

“No, only one of those sea-cows that wished to pay his respects,” laughed Jack, as a blunt nose appeared for an instant above the turgid waters and gave a mighty grunt.

“I hope the others will be less strenuous in their attentions,” declared Mr. Chadwick. “I think that fellow must have dented his nose.”

“I don’t care about his nose so long as he hasn’t damaged us,” declared Tom. “I’m going to shoot one of those fellows if I get a chance.”

“Are they good to eat?” Jack inquired of Captain Sprowl.

“Yes, the natives like ‘em,” was the reply. “I’ve eaten Maneater steaks myself, but they’re as tough as all Billy-get-up; however, as a novelty I suppose they’re all right, as the fellow said when they asked him to eat a dish of French snails.”

Several bends of the river were made in this leisurely fashion. They had proceeded some five miles when Captain Sprowl drew attention to a lawn-like patch of ground sloping down to the river, which was hemmed in by dark-foliaged mahogany trees.

“Looks to me like that would make a pretty fair camping ground,” he said. “I don’t know how you all feel, but I know that, personally, some supper would go about as good as anything I can think of.”

This appealed to all of them, and Jack ran the craft in alongshore. The water was quite deep, even at the edge of the little natural clearing, due to the rapid course of the river which had eaten the bank away into a steep, precipitous ridge. The craft was made fast, bow and stern, to two tree trunks, and they disembarked, carrying Judkins ashore, despite his protests that he was quite able to walk.

Mr. Chadwick, who was somewhat of a doctor among his other accomplishments, took a good look at the man’s injuries. He found that his ankle was badly crushed but not broken, and with care would get all right again. His wrist was more badly hurt, but with the help of the medicine chest which they had brought along, that, too, ought to yield to good treatment.

“Now there ain’t much more of daylight,” said Captain Sprowl, when they had disembarked, “and we want to get grub as soon as possible. I’ll fix up the camp while you boys scatter and get some wood.”

The boys hailed this opportunity to explore the forest about them with a whoop of joy. But as they were starting off, Captain Sprowl hailed them sharply.

“Take your rifles along.”

“What for? We can’t shoot down firewood, and we’ve got our pocket axes,” declared Tom.

“You take your rifles,” repeated the captain. “It’s not a good plan to go snooping about in this neck of the woods without firearms.”

“We might get some game anyhow,” said Jack, as he got his weapon out of the boat; and the others did the same, Dick helping himself to one of the spare stock, for they had brought several from the yacht.

This done, the lads set off into the jungle, promising to keep within call and come back as quickly as possible.

They struck off into the closely growing vegetation and almost immediately found use for their axes. Great lianas or creepers, as thick as a man’s thigh, hung down like serpents from the taller trees, and numerous flowering shrubs and heavily scented bushes barred the way. It was hard work to find any growth that appeared suitable for firewood. Everything was too rank and green for the purpose; but at length they came to a clump of small trees that looked suitable.

“Now watch the Boy Lumberman!” cried Dick, swinging his axe with a vicious swoop at the trunk of one of the smaller ones.

The next minute he uttered an eloquent cry of “Ouch!”

The sharp steel had rebounded from the wood, hardly leaving a notch on it to show where it had struck. The axe handle, too, had “stung” Dick’s hands sharply.

“Well, by the tall timbers of Texas,” he exclaimed amazedly, “what do you know about that? Not a mark on this fellow, and I swung with all my might! They must be made of steel.”

“Something like it, I guess,” said Jack. “I wouldn’t be surprised if this was a clump of young iron-wood trees. I’ve read about them. The wood is so heavy that it won’t float, and too tough to cut.”

“No doubt of that,” said Dick with conviction.

Leaving the iron-wood trees, they made their way a little further into the twilight jungle, and before long found some trees that looked more promising. On testing, these were found to cut easily and soon all three axes were busy felling them and cutting them into lengths easy for transportation.

Jack, too, discovered some dead timber that would make good kindling wood. It was not long before each boy had a good pile of fuel at his feet.

“I guess that’s enough,” said Jack, calling a halt. “We’ll be getting back to camp. Hullo! what’s the trouble now?”

Through the woods had come a loud shout in a frightened, agitated voice.

“Another of those sea-cows,” ventured Dick, “or maybe a sea-bull.”

“No! Hark! It’s the professor!” shouted Jack, as another cry came to them.

“Ach du lieber! Help! Blitzen! Help!”

“Gracious, the professor is in serious trouble of some kind! Come on, boys, this way!” cried Jack, and he dashed off in the direction from which the frantic appeals had come, followed by the other two lads.
CHAPTER XVI. THE CAMP IN THE FOREST.
The lads hastened through the forest with what speed may be imagined. All the time the yells grew louder, showing them that they were proceeding in the right direction.

“Himmel! Ach donnerblitzen! Ouch!” they could hear as they raced along, tumbling over roots and getting entangled in long, serpent-like lianas.

“What do you suppose can have happened?” panted Tom as they ran.

“Don’t know. The professor must have been attacked by some kind of venomous beast or other,” declared Jack. “Hurry up, boys!”

“Better get your rifles ready,” warned Dick, seeing that his weapon was in order as best he could in his haste.

Suddenly they dashed into a small open space at the foot of a big tree. Half way up this tree was an odd sight. The professor, who had evidently climbed up by the aid of some small branches which grew almost down to the ground, was clinging to the trunk with one arm while the other appeared to be thrust into a hole in the tree.

As the boys came to a momentary halt his yells redoubled, and from the interlacing boughs above, a gorgeous bird swooped down and flew at the professor’s head, screeching and flapping its wings and snapping its big beak in a very menacing manner.

“It’s a macaw! A giant macaw!” cried Jack, as he noticed its gaudy, red, green and blue plumage.

“Ach! Take der bird avay! He bite me pretty soon alretty!” shouted the professor.

“Does that mean that he’s bitten him already, or that he’s going to?” asked Dick, laughing at the odd figure the professor cut.

Jack raised his rifle and took careful aim as the macaw hovered about the professor’s head. The next minute his weapon flashed and cracked sharply. There was a shout from the professor and a screech from the bird and it fell dead almost at their feet.

“Good shooting!” approved Tom, picking it up.

“You’re all right now, professor,” hailed Jack; “I’ve killed the bird.”

“Himmel! I vish you could kill its mate!” cried the Teuton piercingly.

“Why? What’s the trouble? Why don’t you come down?” demanded Jack, who noticed that the professor’s arm was still thrust within the tree.

“I can’t. Annuder macaw in der nest inside der tree has mein fingers be-grabbed.”

What was the matter now became plain enough. The professor must have wandered off in search of specimens while supper was getting ready. Seeing a macaw fly into a nest he had climbed the tree and imprudently thrust in his hand to obtain some eggs. Instantly his fingers had been gripped by the bird’s powerful beak, and he was held prisoner. To add to his troubles, the big bird that Jack had just shot had been harassing the disturber of its home in the tree trunk.

Jack felt more inclined to laugh than anything else at the little naturalist’s plight. But he stifled his mirth and hailed the spectacled German again.

“Hold on, professor. We’ll climb up there and kill it.”

“Blitzen, nein! Not for de vurld vould I haf you kill idt!” was the excited response.

“But it’s holding your hand! It will hurt you! You may get blood poisoning!”

“Nein, I haf on a gluff. Idt cannot hurdt me. Idt is a fine spezimen. Can’t you preak indo der tree midt your axes undt dig him out?”

“We might try,” said Jack rather dubiously, “but I should think it would be better to pull your hand out of your glove.”

But by no persuasion would the professor consent to do this. He declared that he was willing to stand on the tree all night if the boys would only do him a favor and dig through the bark and give him a chance to seize the macaw within. Jack clambered up to the professor’s side and tapping the wood with his axe soon saw that it was a mere shell.

“I’ll soon chop you out of that,” he said, giving the wood a hard whack.

“Chently! chently! I peg off you,” urged the professor; “he is a fine spezimen. Nodt for vurlds vould I haf him ge-hurt.”

“The bird isn’t as considerate toward you,” thought Jack as the professor broke off with a cry of pain caused by an extra hard tweak that the bird had given his imprisoned hand.

A few blows smashed the rotten wood away and as it crashed inward, releasing the professor, he lost his balance and slid down the trunk to the ground, landing with a hard bump. The macaw, on the other hand, let go of his fingers the instant Jack smashed the tree open, and with a loud shriek, as if in contempt of the fallen scientist, it flew off through the wood. Nothing about the professor had suffered any injury but his feelings, and he was soon up. But to his disappointment, no eggs were found in the nest within the tree. Apparently it was only used for a roosting place, or else it was not the season for the birds to mate.

They made their way back to camp, laughing heartily over this adventure, and stopping by the way to pick up the wood they had chopped. They found Captain Sprowl all ready for them and a bit alarmed over the shot he had heard, but matters were soon explained. Mr. Chadwick had bandaged and dressed the injured engineer’s foot while they were gone, and he declared that it felt better already.

Not long after their return the call to supper was given, a summons for which all hands were quite ready. It was a novel experience this, of eating in the depths of the dense tropical forest on the banks of an unknown river. The fire blazed up brightly and cheerfully, however, and spread a ruddy glow about the little clearing that chased the dreary forest shadows into the background. After all, their position might have been much worse than it was.

Captain Sprowl was a good rough-and-ready cook, and he had concocted a supper that, while rather mixed as to courses, was heartily enjoyed by them all.

“Well, we won’t starve, anyhow,” declared Dick Donovan, leaning back against a tree trunk after partaking of pea soup and hot crackers, hot pork and beans, jam and two cups of steaming hot coffee.

“No, and to-morrow if we’re lucky, we’ll have turtle eggs for breakfast,” declared Captain Sprowl.

“Turtle eggs,” cried Tom.

“Yes. I saw some turtles crawling out of the water on to that sandy beach above us a while back. I guess they’ll lay their eggs to-night, and in the morning we’ll make a round of the nests.”

“Wonder how some broiled macaw would go?” said Jack, mischievously eying the German savant who was busy skinning the specimen the boy had shot.

“There are many mac-causes why it wouldn’t be good,” quoth Dick solemnly, for which offense he was threatened by the boys with a ducking in the river if it was repeated.

“A macaw,—have you heard this before?—
At a German professor got sore;
It grabbed at his finger,
The prof he did linger,
And now he won’t do so no more,”

chanted Dick, who had a weakness for making up limericks.

“Stow that,” growled Captain Sprowl with mock indignation. “Now then,” he went on, “when you young fellers have quite digested your supper, we’ll set about fixin’ up for the night. You said there was a tent in the ship, Jack?”

“Yes, a light one of balloon silk. It’s seven by nine feet. Is it big enough?”

“Crullers, yes! Big enough for the crew of a down-east whaler, boy. We won’t all sleep in it at once, anyhow. I’ve been thinking that as we’re in a strange place and don’t know just what may be lurking about, we’d better keep watch two and two.”

“An excellent idea,” said Mr. Chadwick.

“Why can’t we sleep in the open?” asked Dick. “It’s plenty warm enough.”

“It’s warm enough, all right,” agreed the skipper, “but if you’d ever had black water fever, you’d know better than to sleep without protection alongside a tropical river.”

“Yes,” agreed Mr. Chadwick, “there is nothing more unhealthy than sleeping out of doors in the tropics,—that is, without any protection. We would better keep up the fire all night, too,” he added.

By the time the tent was up and their scant supply of bedding spread, the boys were quite ready to turn in. But Captain Sprowl had divided the night off into watches, each watch to be taken by one boy and one adult. The first watch from nine to twelve was to be taken by Dick and Mr. Chadwick. The second fell to the lot of Tom and the professor, and lasted from midnight till three a. m. The third watch from that hour until six was to be that of Jack and Captain Sprowl. These matters being adjusted, some green wood was piled on the fire for back logs and in half an hour, with the exception of those on watch, the occupants of the camp were sound asleep.
CHAPTER XVII. THE GIANT SLOTH.
The night passed without incident. It was true that Tom, and the others, too, when their turns came to go on watch, did receive a slight start as an occasional loud scream or cry rang through the forest. But they knew that the outcry was that of some small animal seized by a night-prowling beast, and did not worry about their personal safety so long as nothing approached the camp fire, which was kept brightly blazing.

In the morning, as soon as it began to grow light, Captain Sprowl and Jack, who were on sentry duty, went down to the sandy beach where they expected to find the turtles’ eggs. The captain’s previous experiences in the tropics had instructed him how to look for these delicacies. Nothing about the smooth sand showed where the eggs had been buried; that is, at first glance, but after a close scrutiny the captain found various places where the beach appeared to have been freshly disturbed. Digging into these areas with sharpened sticks, he and Jack soon uncovered numerous deposits of eggs; for the turtles of Brazil lay their eggs in big holes,—each one common to several of them,—filling them to within a short space of the top. The sand is carefully pushed back and the eggs left to hatch by the heat of the beach.

Returning to camp, they awakened the others. The boys would have liked to indulge in a swim in the river, but the captain warned them against doing any such thing as most of the Brazilian streams swarm with alligators and a kind of leech, that when once affixed to the skin is very difficult to remove. So they all contented themselves with a good wash in the not over-clear water. The turtles’ eggs did not prove quite such a treat as the boys had been looking forward to. From reading books of adventure they had the idea that the eggs were great delicacies; but after trying them, they came to the conclusion that the authors who wrote of them with such enthusiasm could never have tasted them. They were strong, fishy-tasting and oily, although, no doubt, in a pinch they would have tasted well enough. Captain Sprowl told them that the natives did not eat them but utilized them in another way.

At certain times a whole tribe would repair to an island known to be used by the turtles for egg-depositing. The caches of eggs were then robbed and the entire mess dumped into a canoe. The mass was then trampled upon, and after a while an oil arose to the surface, which was skimmed off and placed in jars and used for cooking and other purposes.

After the morning meal they naturally fell to discussing plans. Judkins declared himself better; but it was still painful for him to move about. Captain Sprowl could not take an observation till noon, but by a rough calculation he reckoned that they were cast away on the Brazilian coast some five hundred miles to the south of civilization.

It was in the midst of the discussion of ways and means that the professor electrified them all by a sudden proposition. He had been silent for a long time, buried, apparently, in deep thought. Mr. Chadwick had been asking Jack about how long it would be possible for them to fly on the gas-making supply they had on hand. The boy had replied that he figured they had enough on hand to carry them at least two weeks, allowing for evaporation and occasional intervals of land or water travel. Then it was that the professor spoke.

“For how much vill you charter me your machine?” he asked.

They stared at him for a moment. The question appeared so utterly irrelevant to what they had been discussing.

“Ach! I mean vat I say,” repeated the savant. “Are you villing to hire your machine oudt for a trip of say ten days?”

“Why, I—I beg your pardon, but I don’t exactly understand,” said Jack, acting as spokesman for the rest.

“Zo! Perhaps I should ought to haf madt meinself more clear, hein?”

“Well, you did give us a bit of a jump,” declared Jack. “The idea of chartering a machine in the midst of a Brazilian jungle is rather startling when you spring it as quickly as all that.”

“Dot is mein vay,” said the professor quietly, “budt ledt me make meinself plain. You know der object off mein trip down here?”

“In a general way you have already explained it,” said Mr. Chadwick. “You are to collect specimens for a zo?logical society of Germany, and also to bring home a complete account of your exploration of the country.”

“Dot is righdt. Idt vos for dot I vos hoping to gedt you to make me some sordt of a ship dot vould navigate dese vaters. Budt now dings haf fallen oudt differently. Dose foolish mens on der yacht dink dot I come after treasure. Budt neverdeless dey bring der ship chust aboudt vere I vant to go pefore she is ge-wrecked. I suppose dot dey think dot after a vile dey make me tell vere der treasure iss,—hein?”

“I suppose they had some such plan,” rejoined Mr. Chadwick. “You told us that your papers had been ransacked soon after leaving Madeira and that in that way the men discovered your destination. After the mutiny, I suppose they decided to navigate the yacht to her original destination and then, by some means, make you guide them to the treasure. But of course the wreck changed all that.”

“Egzacly, mein friends. Now der point iss dis: I am here, chust aboudt vere I vant to be. I may neffer haf such a chance again to obtain vot I am in search of.”

“Treasure?” asked Dick, his eyes wide open.

The professor gave a sort of laugh, with a note of scorn in it.

“Nodt your idea of treasure,” he said; and then, becoming very serious, he pushed back his spectacles and poised a finger.

“You haf heardt of der mammoths,” he asked, “of der huge beasts dot roamed der earth when it vos young?”

They nodded and looked at him with interest. What could be coming next? That the professor was in deadly earnest, there was no doubt. His leathery cheeks were flushed with enthusiasm.

“Undt you dink dot de mammoths is all perished from der face of der eardt?” he went on catechisingly.

“Well, such is the general opinion of scientific men,” rejoined Mr. Chadwick.

“Den dey are wrong. Dot is, I hope to prove dot dey are wrong,” declared the professor. “I pelieve, undt der are many dot agree mit me, dot in parts of de globe der mammoth still exists. Dot is, certain forms of him. You haf ever heard of der Spanish naturalist Moreno?”

They shook their heads.

“Vell, Moreno heldt der same pelifs dot I undt many savants do. He fitted oudt an expedition in 1900 undt sought der mammoth in Patagonia.”

“Did he find it?” asked Jack breathlessly, prepared for anything.

“Nein. Budt he did findt, in a cave, a skull undt der skin off a mammoth. Der hair on dot skull vos fresh undt dere vos bloodt und skin on idt, showing dot idt hadt been freshly killed.”

They fairly gasped as they looked at the little German. There was no questioning the fact that he was quoting scientific facts. In his precise mind imagination had no place.

“Undt dot skin hadt been removed py human handts, not more dan a day pefore he foundt idt,” went on the professor. “How did he know? Dot skin vos turned insidt oudt undt rolled up!”

“Well?” said Mr. Chadwick.

“Vell, chentlemen, dot skin vos der skin of der chiant sloth, der Megatherium. In past ages dey roamed the South American continent from end to end. Dey vos like der small sloths dot abound here; budt dey vos as big as elefants! Undt,” he paused impressively, “such creatures still exist.”

“Impossible!” declared Mr. Chadwick.

“Nodt at all, mein friendt. To show you how impossible der savants of Europe dink such a ding mighdt be, dey haf sendt me to find such a creature or proof positive dot dey still are living members of der animal kingdom. Dot vos de treasure I vos sendt to findt! A treasure dot dwarfs into insicnificance any mere tiamonts or goldt!”

“And you think that in some remote part of Brazil a living specimen of such an animal may be found?” demanded Mr. Chadwick, the only one of the party able to find words at the moment in the face of the professor’s astounding statements.

“I do not dink idt, I know idt,” declared the little man earnestly. “I do nodt know if I can secure a specimen. Even proof vill be pedder dan nuddings. But dot der Megatherium still lives undt roams der forest, I pelief as I pelief dot vee are here.”

“And where do you expect to find such an animal?” inquired Mr. Chadwick.

“Anyvere towardt der headvaters of der Amazon among der foothills off der Andes. If idt exists idt exists somevere in dot locality.”

“But the specimen you spoke of was found in Patagonia,” objected Jack. “Egzacly. Undt following Moreno’s death a secredt expedition vos sendt to obtain, if possible, a living specimen or proof dot der Megatherium existed. Dey were absent two years. Dere fundts hadt giffen oudt. Budt dey brought back data undt accounts giffen by Indians dot showed dot if der Megatherium existed, idt vos somevere in der solitudes of der upper Amazon. Undt now you know my mission undt vy I vant to charter your ship. Vot do you say?”
CHAPTER XVIII. IN THE JUNGLE.
From the first mention of the Megatherium, the party had become inoculated with a feverish desire to plunge into the adventurous channels the professor’s narrative appeared to open. But the matter involved was far too weighty to be decided in a moment. An hour or more of earnest discussion followed, until at last Captain Sprowl, throwing off all pretense of reserve, said:

“I’m frank to say that I’m for it. It’s two thousand miles from here to the foothills of the Andes on a rough calculation. You kin fly fifty miles an hour, kain’t you?”

“Easily,” was Jack’s reply, “but we can do better if the wind is with us and we develop full power,—say sixty-five.”

“Good enough. Then flying day and night, that brings us to the region we want to go to in about thirty-five hours.”

“That’s right,” nodded Mr. Chadwick, “but there are other things to be considered,—Indians, for instance.”

“Vee vouldt nodt vant to go vere human beings existed,” said the professor. “Der Megatherium, if he exists, vill be foundt far from any place vere peoples of any kindt lif.”

Mr. Chadwick interposed one or two more objections and then was silent for a minute. Finally he turned to the boys.

“Well,” he said, “what do you lads think of it?”

“I think that we could make the trip, sir,” rejoined Jack. “We are well armed. We have some trinkets that we could trade off to any hostile tribe we encountered and gain their good will, and then, too, the very sight of our flying-ship would overawe them if we managed things right. But from what the professor says, we are not likely even to encounter that danger. All we are required to do, as I understand it, is to fly our ship to a region he selects, and from that point organize a search for the Mega—mega——”

“Megaphone,” suggested Dick.

“Well, for the giant sloth. If you ask me, I say—yes!”

“Same here,” declared Tom, promptly, who had been waiting eagerly for a chance to announce himself.

“Yes,” thundered Captain Sprowl, “and we’ll bring that Meggy-meggy-fear-none home again, lashed to the mast.”

“Well, as I would only be in the minority, I suppose I may as well vote in the affirmative,” said Mr. Chadwick.

“I’m only an outsider,” piped Dick, “and as I’ve got no business here anyhow, I don’t suppose you’ll take me. But I say, yes; because if we do get this Mega-what-you-may-call-um and the professor lets me take pictures and write a story, it’ll be the biggest newspaper stunt pulled off for a long time.”

“You’re appointed special correspondent of the expedition, then,” laughed Jack.

“I don’t know how to dank you,” declared the professor fervently. “You haf done a service to science dot cannot be paidt in money, even if ve don’t get der Megatherium. Budt now ve gedt down to business. If vee gedt der Megatherium or proof dot he exists, I agree to pay you fifteen thousand dollars for der use of der Vundership. If ve don’t gedt him, I pay you half dot sum undt five tousandt additional for your services. Does dot suit you?”

“Suits me,” said Jack, almost at once, after a glance had passed between himself and Tom.

“Very vell, den. Dot is arranged mitout fuss or fedders. I gif you an agreement.”

“Oh, that’s all right,” said the elder of the two owners of the Wondership, but the professor tore out of his pocket-book a leaf of paper and with his fountain pen rapidly scribbled and signed a contract.

“If I die, der people for whom I am doing dis vurk vill see dot you gedt der sum agreed upon,” he said, as he handed the paper to Jack, who took it under protest.

The preparations for the trip into the unknown regions to the west of them occupied most of the rest of that day. It was decided to leave Judkins in the camp with a supply of provisions, as no more weight than was necessary was wanted in the air craft,—for that they would have to make much of their voyage by the “air route” there was no question. The engineer appeared quite agreeable to this plan and apprehended no danger. In a week at the outside they were to fly back and see how he was faring.

They decided to make the start the next morning, which would bring them into the region the professor wished to reach about daybreak of the day following. This would give them an opportunity to scour the country and fix a permanent camp.

That evening while the supper was cooking, with the addition of some turtle steaks and fish which had been caught during the afternoon by Dick, they were startled at a crashing and scrambling in one of the tree tops not far off.

Grasping their rifles, the boys started off in pursuit of the animal that was causing the disturbance. They soon arrived under the tree in which it was concealed, but owing to the dense foliage could see nothing but the shaking of leaves and branches as some heavy body moved about.

“Maybe it’s a leopard!” exclaimed Dick. “The captain says there are lots of ‘em about here and we heard some howling last night.”

“No, it’s making too much noise for a leopard,” declared Jack; “besides, I don’t believe that they ever go so high up.”

“Maybe it’s a monkey of some kind,” suggested Tom.

“That’s a heap more likely,” agreed Jack.

“Hullo! It’s moving again!” cried Tom.

“It’s swinging into the next tree. Look!” cried Dick excitedly.

“If you saw it, why didn’t you shoot?” demanded Tom.

“Got buck fever, I guess. Say, fellows, by the meandering monkeys of Moravia, that was the funniest looking thing I ever saw.”

“Why, what did it look like?” asked Jack.

Dick thought earnestly for a minute. Then he looked up brightly as if he had hit on a clever definition.

“Like nothing that I can think of,” he remarked with a grin. Tom aimed a swinging blow at the jester, which Dick dodged easily.

While they were thus engaged, Jack’s rifle spoke sharply. He had caught sight of the odd animal swinging to the tree beyond that to which it had already transferred itself.

There was a great threshing among the branches and an odd sort of squealing cry.

“You hit it, all right,” declared Tom.

“Yes; but I’m afraid it’s got entangled in the branches and we’ll lose it after all.”

“I’ll climb up and get it,” volunteered Dick.

But there was no necessity for this. After a minute’s interval a hairy body came crashing and toppling down, landing with a thud at their feet. As Dick had said, the animal was certainly unlike anything the boys had seen up to that time.

It was a hairy creature, about the size of a large monkey. Its nose was snub, its eyes large and round, and it apparently had no ears. But strangest of all, in among its coarse hairs grew a sort of moss of almost the exact hue of the vegetation adhering to the tree trunks.

The legs were long and powerful, and each foot bore three strong, curved claws, like meat-hooks. It was not until the professor saw the creature that they knew what it was.

The animal was the three-toed sloth, which travels upside down among the tree tops of tropical Brazil like a fly hanging to the ceiling. The moss-like growth amidst its coarse hair was real moss, declared the professor, and was one of those inscrutable devices of nature for protection purposes, rendering the animal almost invisible when swinging against a tree trunk.

“And the Meggy-thing-um-a-jig is the big cousin of this fellow?” asked Tom.

“He is radder de greadt, greadt, greadt gross fader,” responded the German with a smile.

“But surely the giant sloth doesn’t swing from trees?” asked Jack.

“Nein. Idt is peliefed dot he lifs in swampy places undt has a foodt broadt undt flat. Idt is only his grandchildren dot took to der trees.”

“Well, boys,” declared Captain Sprowl, when they exhibited Jack’s trophy to him, “that’s a sign of good luck. We’ve only got to find a critter like that, only forty times as big, and resemblin’ him ‘cos he’s so different, and you get fifteen thousand dollars. It’s jes’ as easy as rollin’ off’n a log—I don’t think.”

With which profound speech the captain continued his culinary tasks with vehemence.
CHAPTER XIX. INDIANS OF THE AMAZON.
The sun was hardly an hour high the following morning before all was in readiness for the start. In fact, the party waited only to despatch breakfast and make a last thorough inspection of the flying auto. All other details had been attended to the night before.

Hearty good-byes were said to Judkins, who had proved himself a decent sort of fellow, and who had had but little part in the schemes of the rascally crew of the Valkyrie. This done, the party got on board and the lines were cast off.

It had been decided to follow the river for some distance further, as the professor and Captain Sprowl had an idea that it might prove to be an arm of one of the larger tributaries of the Amazon. At five-thirty that morning Jack set the propeller in motion and the machine glided off up the river without a hitch.

With rapidly throbbing engines she negotiated bend after bend, and at last reached a spot where the stream appeared to be growing rapidly narrower. As a consequence of this, the current increased in velocity till navigation was difficult.

“This won’t do,” declared Jack, glancing at his instruments; “we have only made fifteen miles in the last hour. If you are agreeable we will go up now. We’ve come as far as we can profitably go on this stream.”

They all agreed with him, and presently a hissing sound told that gas was rushing into the big bag, inflating it for flight. Tom adjusted the hydroplanes to a position fit for aerial use, for they had found that, except on rough water, the Wondership would float as well without her hydroplanes as with them. This was doubtless due to her broad beam and general boat-like proportions.

In the midst of their preparations, or rather just as the Wondership was ready to take wing, there was a rustling sound in the bushes, and without warning a score of savage forms burst through the jungle. It was evident at a glance that they formed a portion of a hunting party, for some of them carried the carcass of a deer. The others, coppery-colored specimens, carried bows, long slender spears and another weapon that looked as if it was formed out of a long tube of bamboo.

For an instant they appeared as much astonished at the sight of the adventurers as the white men were at their sudden apparitions. They stood stock still, staring at the huge swelling gas-bag, the gleaming metal car of the Wondership and the occupants of the craft, as if they had been graven out of stone. This afforded a good opportunity for the astonished party to survey these children of the forest.

Some of them, leaders or head men, apparently, wore ornaments, collars and waist bands decorated with macaw feathers and bits of bone. Others were attired simply in sandals made of bark, and wore a sort of loin cloth made of snake skin. Their hair was thick, fairly long and inky black, their skins, as has been said, of a coppery hue. As to their general build, they were decidedly undersized, almost dwarfs, judged by Caucasian standards. They were, in fact, a hunting party of the war-like Tupi-Guaranian race which roams the forests of Brazil.

All at once, and without giving the party of travelers any opportunity for parley, several of the Indians raised the long pipes to their lips and a rain of tiny darts came about those in the craft. One of these darts struck Dick in the hand and inflicted a painful wound.

“Up, get up! Those blow pipe things may be poisoned!” cried Captain Sprowl.

He snatched up a rifle and in a minute some of the Indians would have paid the penalty of their attack, but that Mr. Chadwick caught the irate mariner’s arm.

“Don’t shoot. They know no better,” he exclaimed.

“Then they ought to be taught,” grunted the angry captain. “Look there, will you? That’s all the harm they mean!”

As he spoke, the Indians retired behind the trees and began to pour in a rain of arrows.

But luckily, Tom and the rest had by this time recovered their wits. The metal panels used to make the Wondership a water-tight craft were slid into place and locked, making the craft a cigar-shaped stronghold which no arrow could pierce.

In the sides of the rounded panels were portholes of thick glass through which they could witness the amazement of the Indians at this move. The darts and arrows, and now and then a spear, pattered and rattled against the metal like hail, but for all the damage they did they might as well not have been thrown. The tough metal turned their points like armored steel.

“Talk about bein’ snug!” cried the skipper admiringly. “Why this craft could go any place without gettin’ harmed.”

“We meant these panels to keep out water in rough weather,” said Jack, “but they do just as well as a protection against Indians. I never thought they’d be put to this use, though.”

“All ready to go up,” he said presently.

“Then let her go!” cried Mr. Chadwick.

The great craft quivered and swayed and then rose straight up from the river while the astonished Indians yelled and then threw themselves on their faces in terror. Up like a bullet from a rifle the graceful craft shot, until it was soaring high above the tree tops. Then the panels were slid back and the passenger part of the machine was once more open to the air.

They looked down at the Indians. Dwarfed to mere specks they could see the Tupi-Guaranians gazing upward and shooting their bows and arrows and their blow-pipes,—the latter form of weapon believed to be peculiar to the Amazonian tribes.

“Well, that shows us what sort of a reception the Indians of this country are inclined to give us,” commented Mr. Chadwick.

“But consarn the pesky skunks, I reckon that this sky clipper can give ‘em all the go-by if it comes to that,” declared Captain Sprowl belligerently. “That way you boys have of turning it into a fort is certainly the greatest wrinkle I’ve struck in a long time.”

“And it’s a use for those panels of which we never dreamed,” cried Tom with enthusiasm.

“What’s the matter?” he asked the next minute, as Jack struggled with the steering wheel.

“I don’t know, the rudder appears to be jammed. Climb out astern there and take a look, will you? Or let Dick do it, he’s sitting behind.”

But Dick was having his hand bandaged, so the task fell to Tom. The young reporter’s dart wound was hurting considerably, and as a precaution against poison Mr. Chadwick, before he dressed the inflamed place, had ordered the boy to suck it so as to extract what poison was in it, in case the dart had been “doctored.” As an additional precaution he tied the boy’s arm above the wound with a handkerchief, twisting it till circulation was cut off.

Tom lifted the movable seat and made his way back to where the rudder frames and braces extended behind the craft like the tail of a bird. He leaned over to ascertain the cause of the trouble Jack had complained about.

As he shoved his face over the back of the craft, something whizzed viciously past his ear, and with a yell Tom tumbled backward, almost on top of Mr. Chadwick.

“What’s up?” exclaimed Dick.

“Th-th-there’s a man out there!” stuttered the astonished Tom. “He’s clinging to the rudder. It’s one of those Indians and he threw a spear at me!”

“Gracious! He must have climbed on to attack us before we went up!” cried Jack.

“Get him inside the ship,” said Mr. Chadwick. “He’ll be killed if he lets go!”

“Let somebody else get him in,” declared Tom. “He nearly took my head off with that spear. It’s not my fault he didn’t, either.”
With a yell Tom tumbled backward.—Page 204.
CHAPTER XX. AN “EEL-ECTRIC” DISCOVERY.
Under other circumstances, the situation might have been almost ludicrous. The Indian, who had so manfully charged upon the impregnable fortress of the Wondership was, almost literally, hoisted with his own petard. Two thousand feet above the earth he was clinging with grim tenacity to the slender framework supporting the rudder. To his simple mind the occupants of the air-borne machine must have appeared as some sort of demons from another world, but he had still retained presence of mind enough to hurl a spear at the first one that approached him, although there was nothing very demoniacal about Tom’s fat and roseate face.

The problem now confronting them was to coax this redoubtable savage to relinquish his position on the rudder frames where he was jamming the steering wires. Captain Sprowl undertook this task. Taking Tom’s place he put on as winsome an expression of countenance as his grim features were capable of assuming.

“Now see here, you benighted son of a sea cook,” he premised, “ain’t you got sense enough to come in out of the rain?”

Although of course the Indian had no idea of what the valiant skipper was saying, he regarded him with some interest. Much encouraged, the captain resumed: “There ain’t no manner of sense in your sitting out there, my man. In the fust place, you’ve got a long way to drop if you get chucked off, and in the next you’re jamming our rudder wires. Savvy?”

The Indian, crouching among the wires and braces, merely stared, not without awe, at the redoubtable Yankee, who, for his part, was glad to see that the Amazonian carried no weapons. The spear he had fired at Tom had apparently exhausted his arsenal.

“That’s my bucko,” went on the skipper coaxingly, “you look almost human already. Now come home to tea like a good lad. Do you hear me, you wooden-faced effigy of a cigar store Injun?” he went on in stern tones. “Come in off that jib-boom, or whatever in thunder it’s called, or by the piper that played afore Moses, I’ll yank you in.”

The Indian didn’t utter a word.

“Better hurry up!” warned Jack. “We’re going down and I can’t do a thing with the machine till that rudder wire is free.”

“There, d’ye hear that, you rubber-snouted kanaka?” roared the skipper, growing purple with rage, his fringe of gray whisker actually appearing to bristle as he spoke. “D’ye hear that, you tree-climbing lubber you? We’re going down! down! down! The next stop’ll be the main floor,—the earth,—and you’ll get a bump that’ll jar the grin off your ugly mug.”

Still the Indian crouched stolidly amidst his “squirrel-cage” of wires and braces. The captain was exasperated beyond measure.

“You putty mugged Yahoo!” he bawled out in a quarter-deck voice. “For the third and last time of askin’:—air you a-comin’ aboard? Speak now or remain forever silent.”

Not a word uttered the quiet, copper-colored figure amid the stern rigging.

“Ve-ry well, then,” growled the captain, and a muscular arm shot out and grabbed the astonished Indian by the scruff of the neck, “I’ll have to get you, my lad.”

With a strength which none of them had guessed the peppery little New Englander possessed, the captain fairly hove the uninvited passenger into the machine. The Indian offered no resistance. He appeared to think that he was irrevocably doomed to death, and that nothing he could do would save him from his fate.

When the captain had hauled him on board, he lay flat on his face in the bottom of the tonneau and uttered not a word.

“Get up thar, and act like a Christian,” exclaimed the captain angrily. “We ain’t goin’ to hurt you, you benighted monkey.”

“I’ll go down,” said Jack presently. “There’s a patch of swamp land yonder that will make a good landing place. We’ll put him ‘ashore’ there. I guess he can find his way home.”

“The only thing to do with him,” declared the captain. “Of all the ongrateful scaramouches ever I seed, he’s the wustest.”

Jack set the craft on a downward glide and came to earth on the edge of a patch of swampy land of some extent. The spot that he had selected for a landing was slightly higher than the rest and was comparatively dry. The big craft came down without a bump, and the pumps began sucking gas from the bag to render the machine less buoyant.

“Now then, you imp of the woods, git up on your hind legs and skeedaddle,” advised the captain, yanking the Indian to his feet.

The fellow uttered a cry of amazement as he saw that he was once more on the earth. He looked wildly around him for an instant.

“Go on. Be off with you!” admonished the captain. “You’ve made us trouble enough.”

Without a word the Indian made a rush for the side of the machine. With one bound he was over it and in another minute the forest had swallowed up his rapidly retreating form. Naturally this incident, which had its serious as well as its ludicrous side, came in for a good deal of discussion by the adventurers, while the bag was being refilled.

In the midst of their talk, Tom noticed some odd-looking holes which were distributed at fairly regular intervals all over the swamp. Motioning to Dick, he slipped out of the machine and proceeded to investigate. The holes were all about seven or eight feet in diameter and filled almost to the top with muddy water. They had every appearance of having been made by man.

Considerably puzzled, the boys examined several of the holes carefully, and by the motion of the water in one of them judged that they might contain fish.

They hastened back to the ship and told the professor the result of their investigations. The little man at once became interested.

“Maybe dey vos spezimens of some kindt,” he declared eagerly. “Ve catch some, hein?”

“Don’t be too long,” warned Jack; “we’re ready to start now, but we can wait a while if you don’t take too much time.”

The professor assured him that they would hurry their investigations, and in company with Tom and Dick he moved off, armed with a big landing net which formed a part of his paraphernalia. He commenced dabbling with this in the hole where the boys had noticed the commotion. Suddenly he gave a shout.

“I godt idt! I godt idt! Himmel! Idt vos a big vun, too. Ach! mein leiber, I got you, ain’d idt?”

As he uttered the last words, the professor, with an adroit twist of his net, drew it out of the water, and the boys saw that it was filled with struggling, snake-like looking creatures of a steely blue hue.

“Eels!” yelled Tom. “We’ll help you, professor.”

As the net was hauled in both boys rushed forward and seized it. Through the interstices of the netting their fingers encountered writhing, slimy bodies.

“Ow! Ouch!” screeched Dick, dropping the net with a yell.

“Wow! They bit me!” howled Tom, shaking his fingers vigorously.

“Nonsense!” exclaimed the professor, cautiously approaching the net and poking it with his fingers. Suddenly he gave a bound backward and gave vent to a yell.

“Himmel! Dey gif me a shock!” he exclaimed dancing about, while his spectacles bobbed up and down on his nose.

“A shock!” exclaimed Tom incredulously. “They bit me.”

“No, idt vos a shock you godt. I ought to haf known bedder. Dese must be electric eels!” cried the professor.

“Electric eels!” cried Dick. “What, really electric?”

“By all means,” was the professor’s reply. “Dey is fulled mit electricidy. Nobody hass ever explained chust how idt is, budt such is der fact. Try dem again undt maype you get annuder shock.”

But Tom wouldn’t. Dick, however, was game, and touched the wriggling mass in the net gingerly with his finger tips.

“Wow! I got another shock!” he yelled. “Say, by the arc-lights of antique Arabia, these eels ought to organize an electric railroad through the jungle.”

He broke out into rhyme at the thought:
“Some electric eels feeling quite jolly,
Said, ‘Let’s run a tropical trolley;
With a motorman monkey,
A sloth for his bunkie,
The eel-lectric trolley is jolly,
By golly!”

“Say, if you do that again, I’ll chuck you into one of these holes,” declared Tom, laughing in spite of himself.

“It’s a wonder that you inventive young geniuses wouldn’t hitch a tank full of electric eels on to your ship,” continued the irrepressible Dick, dancing about at a safe distance. “You would be able to carry food and power then in the same box. When the batteries, or whatever the eels make their current with gave out, you could fry ‘em.”

The professor insisted on taking his electric eels back to the ship, where all on board took turns at “getting shocks.” But it was found that after a few shocks had been delivered the power of the electricity died out. Finally the professor threw the eels back into one of the odd pools that they had made, as it was impossible to carry them with them.

“I had an eel-lusive idea that we might have some for dinner,” said Dick, who was fond of fried eels.

“Shucks,” declared Tom, “I’d just as soon swallow a dynamo as tackle those fellows. You would just about get a dish of them down when you’d start a storage battery in your tummy. Not for me, thanks!”

After the episode of the electric eels Jack lost no time in rising once more. Again they found themselves winging their way above the mighty forest. From time to time silvery streams could be seen flashing among the trees, and here and there were patches of open swamp where tail jungle brush grew rankly, above which they could catch the hot breath of miasmatic vapors. In some of the swamps were big pools, and as the shadow of the flying ship swept over them they could see big alligators flopping off logs in alarm.

At noon, being over an open spot which appeared to be dry and fairly free from brush or obstructions, they decided to descend for lunch. Of course, cooking was out of the question in the air, the boys not daring to risk having a lighted stove under such a volume of inflammable gas as was contained in the big lifting bag.
CHAPTER XXI. THE MARCHING ANTS.
As usual, Captain Sprowl was the cook, with Dick as first aide, otherwise deputy assistant and bottle-washer in ordinary.

“What’s the matter with our strolling off and seeing if we can’t get a shot at something?” suggested Jack to Tom.

“Suits me first rate,” was the response. “Come on.”

The two lads shouldered their rifles and made off into the woods, which were not particularly thick in the vicinity of the open space where they had alighted. As they had not much time at their disposal the boys were ready to fire at the first thing they saw that looked edible. Peering intently about they made their way forward.

Suddenly there was a rush and scramble in a thicket ahead of them and some small creatures rushed out, snorting and grunting.

Jack’s rifle was at his shoulder like a flash. He fired two shots and Tom followed with another.

Having fired, they ran forward quickly, and found that two small animals that looked like miniature pigs had fallen before their rifles. They were indeed a variety of wild swine common enough in that district, and weighed about forty or fifty pounds apiece.

Highly delighted with the results of their marksmanship, the boys set out to return to camp. Tom carried one of the slain porkers while Jack shouldered the other.

“Pork chops for dinner, all right,” chuckled Tom, who was slightly in advance. “I guess——”

Jack, who was a few paces behind, and from whom Tom was temporarily hidden, noticed the abrupt breaking off of Tom’s speech.

“Well, go on,” he admonished. “I’m listening. I——”

“Jack! Jack! Come quick!”

The cry rang through the trees sharply. Jack’s heart gave a mighty bound. Tom’s shout was vibrant with terror. Could he have encountered a band of Indians? Some wild beast?

Dropping his pig, Jack saw to the mechanism of his rifle and plunged forward. The next instant he came to a standstill, literally petrified with horror.

Tom had stumbled over a root and had fallen prone. That much was evident. He was just scrambling to his feet as Jack came on the scene, but already he had perceived the same object that had caused Jack to stop short in his tracks with a sharp intake of his breath and a face that was white as ashes.

Looking upward the boy saw what at first appeared to be a supple highly-colored liana swinging and swaying from the upper branches of a fair-sized mango tree. But this “liana” as Jack had for an instant deemed it, he saw, at almost the same instant, was instinct with life!

Instead of the moving object being part of the tree, or a creeper dependent from it, its supple, cylindrical body and glittering scales showed it to be a monster serpent.

It was an anaconda, the giant boa-constrictor of the Brazilian forests, which has been known to attain the enormous length of forty feet. The monster hanging above Tom was of huge dimensions. At least fifteen feet of its scaly body hung from the tree. How much more was wrapped about the upper branches in sinuous coils, Jack could only guess.

As he gazed on Tom’s predicament his blood fairly congealed in his veins. He felt incapable of action. As if in a dream he saw Tom struggling to rise from the ground and escape the pendent terror above him. But as he moved Jack saw, to his horror, that the anaconda slowly loosened its upper coils and hung lower.

So swiftly, yet so insensibly did it manage its gliding movements, that Jack had hardly taken in the details of the alarming scene before him when the monstrous creature’s head had reached the level of the ground.

With its jaws agape and forked tongue darting, the reptile began slowly oscillating as if trying its range.

“Run, Tom! Run!” screamed Jack, aroused to life at last.

But Tom appeared to be incapable of motion. He paused on his hands and knees as he struggled to his feet and remained in this posture. The horror of his situation appeared to deprive him of the power of locomotion.

Determined to make an effort to save Tom even though he risked his comrade’s life in so doing, Jack raised his rifle and fired. But his hands shook so that his aim was faulty and the bullet flew wide.

But the bullet had one effect, and that the one that Jack least desired. It appeared to arouse the great snake from its deliberate movements.

With a swift, almost imperceptible motion, its head swept forward, and several feet of its coils loosened simultaneously from above. In another instant Jack, almost fainting from terror, saw Tom in the folds of the gigantic reptile. His comrade’s screams of deadly fear rang in Jack’s ears as he gazed on the dreadful drama being enacted before his eyes.

But this inertness only lasted for an instant. Suddenly his mind seemed to clear and he saw with startling distinctness what he must do. Rushing forward he held the rifle as close to the serpent as he dared, and fired.

The bullet took effect in the creature’s body just behind the head and caused it to loosen its folds for an instant with a furious hiss. Its hideous head lunged forward at this new enemy.

Hardly knowing what he did, Jack fired again and again. The automatic spat bullets in a continuous stream. After the magazine was exhausted, the frenzied boy still pressed the trigger. But there was no need for further shooting. The bullets had wiped out all semblance to a head, and the decapitated monster was lashing and writhing its entire length on the ground, for with Jack’s first bullet it had relinquished its grip on the boughs above.

Tom retained his senses long enough to scramble out of the deadly folds of the reptile, and then, staggering a few paces, he toppled over. As for Jack, shouting excitedly, he set upon the body of the great snake and in a frenzy beat it with all his might with the butt of his rifle.

He was conscious of a fierce desire to wipe the creature’s carcass from the face of the earth. It was at this juncture that Captain Sprowl, the professor and Mr. Chadwick came running up, much alarmed over the furious shooting they had heard.

A glance showed what had occurred, and Jack, half sobbing, told the story while Mr. Chadwick brought Tom back to consciousness. After an examination it proved that there was not much harm done beyond a terrible fright. Tom’s body was bruised and sore, however, for the big snake, as is the manner of his species, had begun to crush the boy preparatory to swallowing him, when Jack’s lucky shot turned the tables.

When Tom was somewhat recovered, Professor Von Dinkelspeil drew out a pocket tape measure and began to measure the great carcass which now lay still and cold. He found that the anaconda that had come so near to proving Tom’s end was thirty-two feet in length.

“Vun of der piggest I ever heardt of,” he declared, “although Bates, der English naturalist, says dot he heard of anacondas forty feet long, in der stomach of vun of vich de men who killed idt found a horse de snake hadt ge-swallowed.”

“Well, ‘all’s well that ends well,’ as the poet says,” quoth Captain Sprowl, “but the ugly customer yonder might have made an end of Tom, if it hadn’t been for Jack here. Shake, boy, I’m proud of you. You didn’t lose your nerve for a minute.”

“Didn’t I?” rejoined Jack with an odd smile.

At this juncture, a sudden cry from Dick made them all look round.

“The ants! Millions of ‘em!” he cried. “They’re coming this way!”

“Marching ants!” exclaimed the professor. “Annudder of der vunders of de Prazilian forests. Dey must be coming after de carcass off der snake.”

“Say, they’re covering the whole earth!” roared Dick. “Creeping carnations of Connecticut, I never saw such a sight!”

“Look!” cried Jack suddenly pointing in the other direction from that to which Dick was excitedly drawing attention. “There come some more of them!”

Advancing toward them was what at first sight appeared like a vast undulating carpet of dark brown color. It was about five feet in width and came onward through the forest like a coffee-colored river.

“Sacred cod-fish!” exclaimed Captain Sprowl. “I’ve got a notion that we’d better be doing something pretty quick.”

“What do you mean?” asked Jack, for there was an odd intonation in the captain’s voice.

“Getting out of here, for instance,” exclaimed the captain. “Each of them marching ants is two inches long and is armed with nippers like a pair of pincers. They are coming after the dead body of that snake, I guess, or they may only be out on the war-path as their custom is sometimes. But in any case, we’d better go away from this part of the woods, for if we don’t they’ll overflow us like Noah’s flood.”
CHAPTER XXII. “UP A TREE.”
The Ecitons, or foraging ants of Brazil are the terrors of the forests. Cases have been known in which these marching armies of myriads of the creatures have caused the desertion of entire villages. Animals, even the ferocious jaguar, flee before them, and birds and the minor forms of animal life give them a wide berth. They overwhelm by sheer force of numbers. One of their columns is like a stream of water. When it strikes an obstruction it spreads out till it has covered it. Then the relentless march goes on, leaving behind it devastation and death.

All these facts were known to Captain Sprowl from hear-say, and to Professor Von Dinkelspeil from his books. Yet neither of them had ever actually beheld one of the great movements of these creatures.

But Captain Sprowl’s warning to get out of the way came too late. The jungle on each side of the clearing was thick and too densely grown with thorn bushes and spined plants to permit escape in that direction.

Both paths out of the place were now blocked by the approaching armies advancing from opposite directions. To have attempted to pass by them would have been madness. In an instant anyone rash enough to face the columns would have been overwhelmed from head to foot by a tidal wave of Ecitons.

It was an awkward predicament. The armies approached closer every minute and it speedily became a matter of importance to secure some place of refuge.

The only one that offered was the mango tree from which the anaconda, whose carcass had attracted the foraging bodies, had made its last attack. Luckily, the branches grew close to the ground and it was an easy matter to clamber up into safety.

“Up with you all!” cried the skipper and then bent with a cry of pain.

One of the forerunners of the ant battalions had climbed up his leg and bitten him painfully on the calf.

“Consarn the critter!” roared the skipper, as he slapped his leg and killed his tormentor, “it stings like all Billy-go-long. I wouldn’t care to be sot on by a thousand on ‘em.”

This incident served to hasten their climb into the tree. Thanks to the low-hanging branches already mentioned, they were soon ensconced therein, and, as they thought, out of danger. From their different perches they eyed the scene below with interest.

As far as the eye could reach the ant columns extended. It was, of course, impossible to estimate the numbers in each advancing file, but there must have been millions upon millions of the tiny creatures. Insignificant enough in themselves as individuals, yet in this multiplicity of numbers they were calculated to inspire respect, even fear.

The forerunners reached the body of the snake a short time after the party had clambered into the tree. Within a few minutes the whole serpentine body of the reptile with its brilliant coloring was obscured by the moving mass of ants. They literally covered it from tip to tip and still fresh numbers appeared, till the ground seemed to heave with them, like a carpet placed on a draughty floor.

It was a fascinating sight, and the boys watched it with a deep interest not unmixed with awe. So densely were the tiny creatures packed that they appeared as one solid body rather than an enormous collection of individual Ecitons.

“Gracious!” exclaimed Tom, as they watched. “I hope none of them take a notion to come up here! They could make it mighty unpleasant for us if they did.”

“Onpleasant!” exclaimed Captain Sprowl, “that’s the word and then some, my lad. They’d drive us out of the tree and then——”

He waved his hand at the surging brown mass below in eloquent silence.

“’And the little ‘uns picked the bones—o-h-h-h!’” he sang dismally.

The professor, who was seated astride one of the lower limbs, interrupted at this juncture.

“Here iss luck!” he exclaimed. “Look, mein friends! I catch a fine spezimen!”

He held up in triumph the body of an ant that he had caught climbing up the trunk. It was fully two inches long and armed with a pair of immense forceps as related to the rest of its structure.

“Did that ant climb up the tree?” demanded the captain sharply.

“Ches! You didn’t dink dot it flewed up, hein?” asked the professor, popping the dead ant into his specimen box.

The boys laughed at this example of Teutonic wit. But Captain Sprowl did not appear amused. Instead he gave vent to a low whistle that sounded somehow indicative of dismay.

“What’s the matter?” asked Jack.

The captain, who sat next him on a bough above that occupied by the professor, placed his mouth close to Jack’s ear.

“Don’t say anything or scare the others,” he said earnestly in a hoarse whisper, “but if many of them takes a notion to climb this tree our name is D-E-N-N-I-S, Dennis.”

There came a sudden cry from the professor.

“Ach! here come some more. See, dey chase dot lizard oop der tree. Vunderful! If I haf not see it, I not belief idt!”

He drew out a fair-sized flask and dropped some liquid on the two ants he had just succeeded in capturing.

The ants shriveled up instantly. The touch of the stuff had killed them.

“What’s that stuff?” asked Captain Sprowl sharply.

“Ah! Idt iss a new sordt of insect killer,” cried the professor triumphantly; “der invention of a Cherman. Idt iss too powerful for ortinary use. Idt is only soldt to naturalists.”

“Say, let me have that bottle a minute, will you?” exclaimed the captain quickly.

“Der boddle? Vot for?”

“’Cause in about ten minutes, if we don’t do something to keep ‘em off, the ants is going to be as thick in this tree as they are below,” was the sharp reply. “Look down there now. They’re coming already. Jack, get down below and lend the professor a hand to keep them off.”

Jack did as he was told. He saw that the captain had conceived some plan of using the insect killer in case of an attack by the ants; and he soon realized that the situation called for quick and decisive action. Within a few minutes of his joining the professor, it was all he could do to brush back the invaders. His hands were stung fearfully; but both he and the professor kept bravely at their task.

“Keep ‘em back! I’ll be thar in a minute,” hailed Captain Sprowl, while a strong smell of chemicals filled the air.

With hands that bled from the tiny, powerful forceps of the invading ants, Jack and the savant kept at their task. But it was growing too much for them. In overwhelming numbers the tiny creatures were swamping them like an approaching tide.

“Hurry up!” cried Jack, “we can’t do much more.”

“Himmel! Dey are gedding vurse undt vurse!” roared the professor. “Ach! mein poor handts!”

“Never mind your hands,” admonished Jack, “we must keep them back.”

But every second the tree trunk grew more thickly covered with the ferocious little creatures. Beneath the circle that Jack and the professor managed to keep clear, they swarmed and surged furiously. Escape was out of the question. The travelers were going through an experience that has befallen many a castaway of the jungle. Bones have been found by searching parties, picked clean of flesh and bleaching, after the passing of an army of the marching ants.
CHAPTER XXIII. THE CLEVERNESS OF THE CAPTAIN.
In the meantime Captain Sprowl had obtained the loan of their handkerchiefs from Mr. Chadwick and Dick Donovan. He knotted his own ample bandana to the others and then saturated them with liquid from the professor’s bottle. This done, he lowered the dripping, reeking string of handkerchiefs to Jack.

“Tie this around the trunk of the tree,” he said. “When the ants hit it, it’ll keep ‘em back. It was like this that they used to put wool round trees to keep the caterpillars off, back home.”

“Do you think it will work?” asked Jack anxiously, for the situation was becoming critical. It seemed almost unthinkable that they could be in actual peril of their lives from creatures not much bigger than a good-sized bluebottle fly. And yet a jaguar would have been a less dangerous foe than these myriads of tiny creatures, with ten times a jaguar’s ferocity in their minute make-ups.

“Well, boy, if it don’t work, it’s all up with us,” declared the captain solemnly.

Aided by the professor, who at once saw the utility of the contrivance, Jack managed to tie the bandage of handkerchiefs around the tree-trunk.

“When it gets dry, douse it with some more of this stuff,” said the captain, handing down the bottle of chemicals.

With an eagerness that may be imagined Jack and the professor watched the first ants that swarmed up the barricade of handkerchiefs. They dropped like files of soldiers storming a fortress wall that bristles with machine guns. Thousands and thousands of them fell from the tree as they encountered the poison-soaked bandage; but still the swelling ranks behind pushed the vanguard on.

From time to time Jack moistened the bandage afresh, and after what appeared to be an eternity of waiting the ants began to slacken in their attack. By slow degrees they retreated till only the masses on the ground were left.

“Scatter some of the stuff among ‘em!” called Captain Sprowl.

Jack spattered the rest of the contents of the bottle over the still swarming myriads on the ground. Wherever it fell an immense patch of dead ants instantly appeared. But at last it was exhausted. Luckily the ants appeared to be reforming for another march, and yet it was a long time before it was deemed safe to descend. When they did so, a strange sight met their eyes. They had been imprisoned in the tree for not much more than two hours. Yet in that space of time the ants had literally cleaned the bones of the dead snake and wrought havoc with the carcasses of the pigs.

“Lucky thing you had that bottle along, professor,” remarked Captain Sprowl, soberly. He added nothing more. He did not need to. They could all supply the alternative for themselves.

A hasty return was made to the Wondership where they found everything as they had left it. A hurried meal was then eaten, and within half an hour they were once more on the wing.

All the afternoon they maintained steady flight toward the westward, and that evening beheld a magnificent sunset. Great masses of gold, purple and scarlet cloud were piled up like dream palaces in the west. Beneath this Fata Morgana of surpassing brilliancy, lay a line of deeper purple, like the crest of an advancing billow.

“See that?” asked Mr. Chadwick, pointing out this darker line.

They all nodded.

“Well, take good notice of it, for that is our first sight of the Andes,” responded Jack’s father.

The words held a thrill. Somewhere in the foothills of that vast and historic range, if the professor’s theories were not all at fault, roamed a beast that had somehow survived the march of the ages. Over toward that sunset, too, had they but known it, strange, wild adventures awaited them. But no idea of what the future held was in the minds of Jack and Tom as they tramped off in search of wood for the evening fire, after the machine had been brought to earth in a stretch of rocky ground, bordered by a river on one side. On the other fell the sombre shades of the melancholy forests.

The boys made for the edge of the river where patches of small trees grew. Here they were more likely to find the firewood for which they were searching than amongst the towering forest giants.

The stream was a melancholy, slow-flowing, muddy water course. On the opposite bank grew mighty trees with a tangle of jungle about their roots, and with long pendant creepers trailing down into the chocolate-colored river. In the evening air a dank, unwholesome smell pervaded the atmosphere. Some gray herons flapped heavily up from the muddy banks as they approached, and an alligator slipped off a log and glided into the water.

What was their surprise, then, in this desolate spot, which they had good reason to suppose they were the first to invade since the beginning of time, when on the bank they perceived a large canoe. It was a clumsily-built dug-out of unusual size, and as the boys got closer to it they soon saw that it was long since it had been used. One side was rotted away and green slimy ooze, gendered by the rank mud, had overgrown it from stem to stern.

Inside it was a big earthen jar, which might at one time have contained water or food, more probably the latter. A broken paddle was near it and another object which the boys did not investigate just then. For something else had attracted their attention.

This latter was the sight of several bones, undoubtedly human, that lay by the side of the mouldering canoe. Evidently the bones were all that remained of the navigators of the ill-fated craft; but whether they had met their death at the hands of a human enemy, or had fallen prey to a jaguar or alligator the boys were, of course, unable to decide.

“Ugh! This place gives me the shudders,” exclaimed Jack, turning away. “Let’s get busy over that wood and go back.”

“Right you are; but let’s have a look at what else there is in the canoe first,” rejoined Tom.

“That’s so. We might as well look. After all, it may afford us a clew to the fate of the poor devils whose bones lie yonder,” replied Jack.

The bottom of the canoe was inch deep in slimy ooze, and out of the stuff the boys excavated a skin bag containing some hard objects and an odd little figure of a squatting man, with a hideously deformed face, fixed in a perpetual laugh. This little idol, for such unquestionably the thing was, was about as ingenious a bit of hideousness as could be imagined. It was not more than a foot high, and was wrought out of greenish stone. It was carved in a squatting position with the legs tucked under a fat body, tailor-fashion.

But it was the face, tiny as it was, that sent a chill through the boys’ veins. There was something diabolical in that frozen laugh. It was as if the miniature god was mocking all mankind with a grin of bitter irony.

“Nice little thing to have about the house on the long winter evenings,” chuckled Tom. “Cheer a fellow up when he felt blue, wouldn’t it—not?”

“I suppose the folks it belonged to held it in enough veneration,” rejoined Jack, holding the hideous little figure up in the dying light. “Anyhow, the fact that it was in the canoe shows that those chaps must have been killed by an animal or a ‘gator. If natives had finished them off, they wouldn’t have left this thing in the canoe.”

“Unless they were scared of it,” commented Tom; “it’s enough to give anyone the shudders.”

“It’s not ornamental certainly; but it’ll make a bully souvenir of the trip. What’s in the bag, I wonder?”

“Don’t know, I’ve put it in my pocket. We’ll take a look at it when we get back to camp. Right now our job is to get busy with the axes. They’ll think we’ve run into more trouble if we don’t hurry up.”

Acting on Tom’s suggestion, they were soon making chips fly, and in a short time had wood enough for a cooking fire. The night was too warm for there to be any necessity of a bigger blaze; especially as they meant to resume their journey immediately after the evening meal.

There was so much to be discussed at supper that the boys did not have an opportunity to bring up the subject of their finds till afterward. Then they told of their discoveries, and Jack proudly exhibited his idol. The professor pronounced it to be of ancient workmanship, perhaps the handiwork of some vanished race. Some hieroglyphics were inscribed on its base, but what they stood for the professor, although a man learned in such matters, was unable to decipher. He declared that the characters did not even approximate any known form of hieroglyphics.

“Well, anyhow, he’ll make a fine mascot,” declared Jack; “we’ll call him Billikin and hang him in the front of the flying auto for good luck.”

This was hailed as a good idea, and amidst much laughter Mr. Billikin was secured to one of the forward stanchions of the Wondership.

“But say, how about that bag of yours?” demanded Jack of Tom as soon as the mascot had been triced up.

“Let’s have a look at it right now,” said Tom, pulling it from his pocket.

The pouch was made of some sort of skin. Mildew had all but obscured some markings on it that had apparently once stood out in brilliant colors. It was fringed and evidently had been wrought with much care. Tom shook it and the contents rattled.

“Give you three guesses,” he cried.

“Bullets,” came from Dick.

“Reckon that’s right,” grunted the captain; “some of those chaps may have had an old muzzle loader.”

“Sounds like rocks,” was Jack’s guess, “roll them out, Tom.”

Standing close to the firelight, Tom opened the bag and shook its contents into his open palm. Six octagonal objects rolled out.

The next instant there was a simultaneous gasp from every member of the party.

“Diamonds!” shouted Captain Sprowl, the first to recover his breath.

“Yes, and such diamonds as are rarely seen,” cried Mr. Chadwick. “Why, Tom, lad, you’ve found a fortune!”

“Supposin’ they’re fakes like those colored gems we got in Yucatan?” said the practical Tom, holding up one of the stones so that the firelight was reflected from it in a myriad prismatic tints. Its brilliance was fairly dazzling.

“If they’re fakes,” declared the captain solemnly, “I’ll tell you what I’ll do.”

“Well?” said Jack.

“I’ll eat ‘em without sass, by ginger!” exploded the mariner. “Boys, if them ain’t ‘gems of purest ray serene,’ as the poet says, you may call me a double, doll-goshed, Sauerkrauter!”

“Rather than call you any such names,” laughed Mr. Chadwick, “we’ll assume that they are veritable diamonds. Tom, congratulations; you’re a millionaire.”

“You mean we’re millionaires—or at any rate thousandaires,” retorted Tom. “You don’t suppose I’m going to hog them all, do you?”

“Vell, for my pardt, if I can findt idt a Megatherium, I vouldn’t exchange him for a bucketful of diamonts,” declared the professor.

“Well, at any rate, the stones will do us no good till we can return to civilization,” said Mr. Chadwick, decisively. “They’re of not so much good here as a tin of corned beef. And so, gentlemen, if you are ready we may as well be pressing on.”

“Suits me,” declared the captain, “but I’d suggest that one of us takes care of them gems. Mr. Chadwick, you take ‘em. If that boy keeps ‘em, he’ll be giving ‘em to an anaconda or something before we get through.”

“I guess you can take better care of them than I can at that, uncle,” said Tom, willingly handing over the bag to Mr. Chadwick, “although I don’t think there’s any chance of my getting mixed up with any more big snakes. I’ll keep too bright a lookout in future for that to happen.”

Mr. Chadwick placed the gems in a pocketed belt that he wore under his other garments and which he used for the safekeeping of his money and other valuables.

As the flying auto shot up from the ground and continued on its westerly course, there arose above the steady drone of the engine an odd, screaming sort of sound. At first the boys thought it proceeded from some defective bit of machinery or some part of the motor that was out of order. It was Dick’s sharp ears that traced the sound to its true source.

“It’s the wind rushing into old Billikin’s mouth,” he exclaimed.

“Hoo-oo-oo-oo-oo!” responded the idol, the purpose of whose open jaws now became apparent. Possibly the priests of the ancient idol used to swing him through the air, thus producing the queer sound that held a note of menace in its dreary wail. As the ship rushed on faster through the night the voice of the idol became louder and more strident.

“Whoo-oo-oo-oo-oo?” it seemed to demand.

“Who, you grinning old Billikin?” cried Tom, gleefully. “Why, us, you howling monstrosity. You’re going to bring us luck, do you hear?”

The only reply to his outburst was the melancholy, banshee-like wail of the queer image.

“I dunno know about luck,” muttered the captain to himself; “all I know is that that blamed thing gives me the shivers.”
CHAPTER XXIV. THE LION’S MOUTH.
The travelers took turns at brief snatches of sleep during the night. The course was due west and there was nothing to be done but to keep the flying craft on its track. Above them the soft tropic stars shone brilliantly. Beneath the flying car was immeasurable blackness. The altitude set by Jack when Tom relieved him at the wheel at midnight was twenty-five hundred feet. This height was maintained throughout the hours of darkness, Tom gauging his height by the barograph, which was, like the other instruments, illumined by a shaded electric light. The side lights or the blindingly bright electric searchlight were not used, as it was not deemed advisable to attract any attention to the flying craft needlessly, and for all they knew they might be flying into the country of hostile tribes.

At last the dawn began to flush redly behind Tom’s back. In less than half an hour it was broad day. What a sight met their eyes! For sublimity and beauty it was the most powerfully impressive any of them had ever beheld. Possibly the height from which they surveyed it lent it additional charm; but even the stolid captain was moved to exclamations of admiration.

Before them were wooded slopes covered with verdure of the most brilliant green. Amidst this verdant carpet were patches of cleared land on which grew what resembled corn. In other cleared patches other crops were flourishing. Directly under their keel was the mighty forest, stretching, as they knew, without interruption to the coast, two thousand miles away.

Beyond the wooded slopes the ground rose abruptly upward, piling skyward in ever increasing majesty and ruggedness to where, sharply outlined against the flawless blue sky, were the sharp peaks of the mighty Andes. The foothills beyond the fruitful slopes already mentioned were, curiously enough, almost bare of vegetation, save for here and there an isolated clump of trees.

Their slopes were cut up and criss-crossed by gullies of unknown depth, and bore the scars of what appeared to be volcanic action. From a small peak not far off, and glaringly conspicuous by its height amidst the other slowly rising foothills, smoke was curling upward in a yellowish column.

But it was the country below them that occupied their immediate attention. From the cultivated patches it was evident that they were flying above a region inhabited by a thrifty race of Indians. The point was, were the inhabitants friendly, or were they like many tribes of the upper basin of the Amazon, possessed of an unalterable hatred of the white man? Much hinged on the answer to these questions.

As they flew along, the question of descending was discussed at length, and they finally, on motion of Captain Sprowl, reached the conclusion that they would descend. But the gas was not to be exhausted from the bag, and in case of attack they were to be ready for instant flight. To attempt to oppose the Indians in their own territory would be folly of the worst sort. It was, therefore, agreed that in case they encountered hostility they were to make discretion the better part of valor and seek safety in the upper air.

They had hardly concluded their consultation before, below them, they saw a large village. It was arranged in the form of a circle, the huts, mostly thatched with palm leaves, with walls of the same material, converging to a common centre. It was, in fact, much as if the huts had been the spokes of a wheel, the hub of which was formed by a more pretentious structure, built, apparently, of blocks of rough stone, probably quarried in the volcanic-looking foothills.

From the village, roads and paths could be seen through the forest in every direction, leading to the fields. As the ship flew, droning like a giant beetle, above the village, its inhabitants were thrown into much the same flurry as possesses a chicken yard when the shadow of a hawk floats across it.

Men, women and children could be seen running from the huts and standing with upturned faces gazing at the monstrous creature of the skies. They could see that most of the men carried spears and bows, and through the glasses they also made out that many of them were armed with bamboo blow-pipes peculiar to the Amazonian tribes.

“Well, what do you think of the prospects?” asked Mr. Chadwick, turning to the skipper, who had been using the binoculars.

“I reckon it’ll be all right to go down,” rejoined the captain slowly, “but have Tom and Dick get the rifles ready first. Have them out of sight but handy and ready for instant use. We may have a tussle; but if we want to get any reliable information about them elephant sloths we’ve got to get it from Injuns. Otherwise, we might hunt about here for twenty years without getting any closer to the critter.”

Jack swung the flying craft in big, lazy circles, while Tom and Dick slipped magazines into the automatics and placed fresh ones ready to use in case there was any necessity. The weapons were then laid out of sight, as they had no wish to antagonize the Indians by a show of force. When all these preparations were concluded Captain Sprowl, who, by common consent, was leader of the adventurers at this stage of their travels, gave the word to descend.

There was a patch of cleared ground outside the village and Jack aimed the great flying auto toward this. By this time the crowd had increased till the village was swarming with humanity. Suddenly, as they shot downward, they saw an odd procession emerge from the central building. Several men in scarlet robes appeared, escorting a tall man dressed entirely in white.

“That’s the king, or chief, or whatever they call him, I reckon,” remarked Captain Sprowl. “If we can make a hit with his nibs, we’re all right.”

“Wonder what those red fellows that look like bottles of chili-sauce, are?” asked Dick, the inquisitive.

“Priests, I guess, or suthin of that nature,” was the reply of the captain, “and say, young fellow, you don’t want to get disrespectful among these folks. They might resent it and their resentment takes the form of a spear in the ribs.”

The flying auto came to the ground as easily as usual; but Jack experienced some difficulty in clearing a path for his landing. Far from running from the machine, which must have been the strangest they had ever seen, the natives appeared to be more curious than alarmed. They crowded about it and several narrowly escaped being run over.

“I don’t much like the look of this,” muttered the captain to Mr. Chadwick. “They don’t scare worth a cent, and that’s a bad sign. Look at ‘em size us up, too. Don’t a soul of you leave the machine whatever happens, till I give the word,” he added.

“Hullo! Here comes his nibs,” said the irreverent Dick, as the crowd gave way respectfully and the tall man in white, with his scarlet-robed retainers, advanced.

As he drew nearer, they saw that although he appeared to be tall, the white-robed man was only altitudinous by comparison with his subjects, as they guessed them to be. These latter were much like the Indians they had encountered the day before, only a trifle more intelligent looking. They had the same small stature, copper-colored skins, straight black hair and sloe eyes. Several of the younger ones bore a striking resemblance to dark-colored Japanese.

The red-robed men, surrounding the chief, wore circles of feathers like coronets around their heads, and several of the villagers sported the same decoration. As only those so decorated were armed with spears, or bows or blow-pipes, the travelers assumed that they formed the warrior or hunter class. In this they were correct.

“Anybody speak English?—United States?” asked the captain, as the white-robed chieftain approached. He was anxious to remove any impression that they were Spaniards or Portuguese, two races that the Indians hate with an undying resentment for their past cruelties. The captain bowed low to the ruler as he spoke and the others followed his example.

“Spanish, then? Anybody speak Spanish?” asked the captain in that language.

One of the red-robed men stepped forward. He was a fine-looking man with an expression almost of intellect which the others, even the chief, notably lacked.

“I speak Spanish,” he replied in that language, which they learned later he spoke with a most barbaric accent, “but you are not Spaniards?”

“No, we come from the north, from America,” rejoined the captain, with a sweep of his hand toward that point of the compass.

The red-robed man turned to the chief and spoke rapidly in a not unmusical tongue. The white-robed man nodded comprehendingly and then the inquisitor turned to the captain again. Of course the conversation was not understood by the boys but the captain gave them the details afterward.

“You come in that flying canoe?” was the next question.

The captain deemed it wise to reply in the affirmative. He added that having heard wonderful things of the country they had come to pay it a friendly visit.

He said nothing just then of the real object of their journey, thinking it more prudent to leave this till later on.

This reply being translated to the chief, that dignitary himself appeared to suggest a question. It was one that was to the point, too.

“What do you want in this country?” asked Red-robe.

The captain dared not hesitate, and under the circumstances concluded that the truth was the best thing to tell.

“To hunt, to study your customs and to take back to our people the friendship of this great tribe,” he replied with a touch of diplomacy.

The red-robed man appeared satisfied. He turned to his chief and spoke rapidly. The chief also appeared gratified, and the captain began to think that all was to go as smoothly as they could have desired. But suddenly their hopes were dashed, and that in an entirely unexpected way.

While the red-robed interpreter was talking to the chief and the villagers stood gaping around the flying craft, a murmur ran through the assemblage of red-robed men. One of them, a powerfully built fellow with a villainous squint, was pointing out something to the others which appeared to cause them the greatest excitement.

Suddenly the one who squinted bounded over toward the chief and tugged violently at his sleeve. He spoke rapidly, excitedly pointing at the air craft. The chief frowned and a murmur that had an unmistakable intonation of anger buzzed among the central group.

“What’s up?” asked Jack anxiously. “They’re mad about something, aren’t they?”

“Wait a bit, here comes our friend,” was the reply. “Hold your horses, now.”

The interpreter stepped straight up to the captain and spoke swiftly in his imperfect Spanish, while the others pressed closely about the machine. It was clear that a crisis of some sort was pending. But what, they could not imagine.

“Chekla, our king, wants to know, why, if you come from the far northland, you carry on your ship the god of the Iribis that was stolen from us ten years ago?” demanded the interpreter in tones that unmistakably called for a satisfactory explanation.

The captain explained that they had found the idol and that they were glad to be the means of restoring it to the tribe. It was partly for that purpose, he added tactfully, that they had made their long journey through the air.

Chekla impatiently desired to have the captain’s explanation translated to him at once. When this had been done, his brow clouded and he shot out some angry words. The red-robed man turned to the captain.

“Chekla says that the white men are liars and sons of liars,” he said in a clear, ringing tone.

At the same instant the red-robed man with the hideous squint uttered a loud yell. It appeared to be a signal of some kind, for almost simultaneously the air was filled with flying spears and darts.
CHAPTER XXV. THE TRIBE OF CHEKLA.
“Up with the panels! For your lives!” shouted Captain Sprowl, who had guessed what was about to happen the minute the interpreter opened his mouth.

It was this that saved them from the flying hail of spears and darts. As the grizzled seaman shouted his warning, they ducked down simultaneously and Tom pulled the levers that ought to have sent the panels into place, instantly converting the flying auto into an impregnable fortress. But it was just at this critical moment that an unexpected hitch occurred.

The panels refused to move!

“Up with them, quick!” roared the captain.

“Hurry!” cried Mr. Chadwick.

“I—I can’t make them work!” panted Tom, struggling with the levers, “they’re stuck or something.”

“Great dolphins!” groaned the captain. “It’s all up with us then.”

Before Jack had time to inflate the already well-filled gas-bag sufficiently to rise, a wave of humanity broke over the side of the machine. There was no time to snatch up the rifles, hardly an instant in which even to raise their hands. Within ten seconds from the time the first spear whizzed through the air above the adventurers, crouching low in their craft, they were prisoners of Chekla’s tribe.

Here was a fine ending to all their hopes! From the yells and shouts that rose about them they guessed that they might look for scant mercy at the hands of the Indians, who evidently thought that they had had something to do with the stealing of the idol.

They were hustled out of the machine by a score of hands and marched none too gently toward the central building. As they went, they had the satisfaction of seeing the little stone god that was to have brought them good luck, stripped from the stanchions by some of the red-robed men.

It was held aloft while a low, dismal sort of chant filled the air. Many of the Indians prostrated themselves before the upheld image. Evidently its return was regarded as being a momentous occasion.

“What is going to be done with us?” Captain Sprowl demanded of the red-robed Indian who had acted as interpreter and who, with two of his companions, accompanied the boys and their friends to the central house.

But the interpreter affected not to hear.

“Looks mighty bad,” muttered the captain to Jack, who was alongside him; “in fact, I don’t see how it could be much worse. These fellows were inclined to think that we were all right and some sort of little tin gods ourselves, till they saw that pesky idol. Then it was all off.”

“It was all my fault for putting it there,” lamented Jack bitterly. “Well, it’s proved a fine mascot—I don’t think.”

Nothing more was said, and the prisoners trudged along in silence in the midst of the throng that enveloped them. No attempt was made to offer them any violence, but somehow the very apathy of the crowd appeared more ominous than if they had resorted to active resentment. As Jack thought to himself: “It looks as if they had our fate all cut and dried.”

As if in answer to his unspoken thought were the next words of Captain Sprowl:

“Whatever is going to happen to us, these fellows know before it comes off. But we’ve got to put the best face we can on the matter and show them that Americans ain’t going to be scared out of their seven senses by a bunch of image worshippers.”

Insensibly the doughty little captain threw out his chest and glared about him at the capering Indians that surrounded them.

“I wish I had my hands free; I’d spoil some of your ugly mugs for you,” he grunted.

Suddenly the throng broke into a measured chant. It rose and swelled with hideous lack of harmony to the white men’s ears. But nevertheless the chorused burden of the thing was unpleasantly suggestive. The prisoners found themselves actually glad when they reached the central stone house and were escorted inside by the two red-robed priests and six of the feather-ornamented natives.

Once inside the place, the great doors by which they had entered were closed on the mob outside, shutting off their depressing chant. They noticed that the doors were formed of a sort of white stone of immense thickness but beautifully carved, although what the carvings represented they could not make out. They were hurried along too fast for that.

It was evident, however, that the stone structure was, in part at any rate, a royal residence. Within the stone doors was a circular chamber capped with a dome of really beautiful proportions, considering the fact that the Indians must be ignorant of even the fundamental principles of architecture or geometrical design. In fact, they learned afterward that the stone palace was of extremely ancient origin, the work of some forgotten and highly civilized race, possibly allied to the intellectual Aztecs. Chekla’s tribe had simply found the place there and built up a village around it.

The domed central chamber was furnished with mats and hung with skins and spears, and the walls were ornamented with crude carvings. It was without windows, being lighted by means of openings in the stones set in regular rotation around the base of the dome. At each side, however, was a low doorway, hung with curtains of some sort of plaited grass. Through one of these they were escorted and found themselves in a passage, at the other end of which was another door.

They passed through this and entered a rock-walled chamber absolutely bare of any sort of furniture or fittings. It had a damp, musty sort of odor attaching to it and this, together with the fact that the passage had inclined downward rather steeply, led them to believe that they must be underground.

But wherever they were, it was evident that they had reached their destination. The red-robe who had acted as interpreter spoke to his assistants and they released the captives. Then they backed out slowly, menacing the white men with their spears in case they might attempt to “rush” them.

They reached the doorway, and still holding their spears in threatening postures, backed out. The red-robed man was the last to go. As he vanished a stone door poised on unseen hinges swung noiselessly into place. The prisoners exchanged despairing glances. Under what conditions would that door be reopened? Would it be when they were led forth to death or torture?

A search of the rocky chamber, made as a forlorn hope, without any idea of finding a place by which an escape might be effected, showed that, with the exception of the door and a sort of lattice-work opening in the ceiling through which light and air came, the place was solidly walled in.

“Well, I don’t see what we can do except possess our souls in patience and sit down and wait for what’s to come,” declared Captain Sprowl, when the examination had been concluded.

“There’s nothing else to be done,” agreed Mr. Chadwick despondently.

“Chentlemen,” spoke up Professor Von Dinkelspeil, “dis is mein fauldt. I cannodt ask you to forgive me, budt I vould radder haf nefer seen der country dan dat dis shouldt have happened.”

“It’s not your fault, professor,” declared Mr. Chadwick warmly; “we undertook this expedition knowing what risks we were facing, and we must meet our fates like men.”

“What do you think will become of us?” asked Tom in a doleful tone.

“I can form no idea,” rejoined his uncle. “I hardly think that they will dare to proceed too far. This country is not absolutely inaccessible and Judkins, in the event of the worst happening, would take the news to the outer world and we should be avenged.”

“A lot of good that would do us,” snorted Dick Donovan.

“It’s your own fault that you’re here, anyhow,” snapped Tom irritably.

“True enough,” admitted Dick, “I didn’t mean to complain. I can face anything we’ve got to go through as an American should. At least, I hope so.”

Conversation languished after this. They sat leaning against the walls of the place, each busied with his own thoughts. But the undaunted professor was busy examining the walls. In his scientific ardor in gazing at the many queer scrawlings with which they were covered, he appeared to have forgotten everything. Suddenly he gave utterance to a sharp exclamation.

“Himmel! Vos is dis?”

And then the next minute his voice rang out sharply, trembling with suppressed excitement:

“Chentlemen! Look! I haf foundt idt!”

For one joyous instant they thought that he had discovered a way of escape. But they soon saw that it was one of the wall carvings that had attracted his attention and caused his outburst.

“What is it? Nothing but a hunting scene, ain’t it?” asked the captain, who was nearest to the excitable German.

“Precious badly done, too,” he added. “I know kids at home in Maine, eleven-year-old kids, that could do better than that.”

“Ach! Dot is nodt idt!” exclaimed the professor impatiently. “Idt is nodt a vurk of arts dot I know. Budt idt iss something bedder—idt iss a picture of der hunting of der Megatherium!”
CHAPTER XXVI. DIAMONDS VS. FREEDOM.
“If you could show us a picture of how to get out of here, I’d a heap rather see it,” snorted the captain indignantly. “What good does that critter with the merry-go-round name do us, when we’re penned up in here? Can you tell me that?”

But the professor was deaf to the New Englander’s scornful remarks. With a sheet of paper and a pencil he was busy taking a rubbing of the scrawled picture on the wall.

“Idt gorresponds in efery impordandt detail midt der pictures in der files of der society in Ber-r-r-lin,” he declared.

“Yes, and a fat chance your drawing has of ever sharing a bunk with it, if we don’t sight a change in the weather pretty soon,” growled the old sailor.

But the professor was deaf to these remarks. He worked painstakingly till he had reduced to paper a complete rubbing of the wall picture. Then he drew out a sketch book and made a carefully detailed drawing of it. As he worked, he actually hummed an odd little tune to himself. For the time being, in the glory of his discovery, he had completely forgotten in what grave danger he, and all of them, stood.

It was about mid-afternoon that the lattice-work at the top of the chamber was removed and some food, in stone jars, was lowered to them. With it came a jar of water and some coarse kind of bread made out of corn. The stuff in the jars proved to be some sort of stew, with peppers and other vegetables in it. It was not at all bad and they made a hearty meal, using a small cup in turns by way of a spoon.

They felt somewhat better after the meal, such as it was, and while the professor continued his scrutiny of the walls, the others discussed their situation in all its bearings. The captain gazed longingly up toward the lattice which had been replaced after the food had been lowered.

“If only we had some way of climbing up there,” he said, “we’d at least have a fighting chance. That is, pervidin’ these varmints ain’t bust up the flying ship by this time.”

This last was not a thought to ease their anxiety. If they were to escape at all, they knew that it must be by means of the flying auto-ship. If the Indians had demolished it, they would not be much better off even if they did escape from their prison. In that trackless jungle they could hardly go a league without getting into difficulties. It would be a simple matter for the Indians to overtake them and effect their re-capture, in which case they would be even worse off.

“I wonder if it wouldn’t be possible to bribe one of them to give us our freedom,” said Mr. Chadwick, after a long silence, during which he had been absorbed in deep thought.

“How do you mean?” asked the captain. “These chaps have no use for money, and what else could you offer ‘em?”

“The diamonds,” rejoined Mr. Chadwick quietly.

“By the Flying Dutchman, I’d clean forgotten all about ‘em! Maybe we could buy one of ‘em in that way. It’s worth trying, anyhow. Are you sure you’ve got ‘em safe?”

“Here they are,” said Mr. Chadwick, diving into his garments and producing from his belt the six glistening stones.

The captain selected the largest and balanced it in his hand, toying with it as if he found a delight in its flashing, pellucid beauty. Mr. Chadwick had slipped the others back into his belt.

“Cracky, what a stone!” muttered the captain, as he examined the diamond. “It’s a king’s ransom, that’s what it is, and here we are sitting around like bumps on a log and might as well be at the North Pole for all the good it is. Hullo! What’s that?”

A shadow had suddenly cut off the flood of afternoon sunlight that was pouring into their place of captivity through the lattice work grating. They all looked up swiftly and beheld the face of the red-robed interpreter. At once Captain Sprowl made a rapid movement to conceal the stone, but he was too late. The Indian, as had been noticed by them, had a remarkably expressive face. They could read on it as plain as print, as they looked up at him, that he had seen the diamond.

At almost the same instant his countenance vanished.

“There! Consarn it all!” grumbled the captain. “Now the fat’s in the fire for fair. He’s off to see the rest of the bunch and tell ‘em about the diamond. It’s all off now.”

“Do you think he will do that?” asked Mr. Chadwick.

“I do. Don’t you?” asked the skipper with some surprise.

“No, I don’t.”

“Why not?”

“For one reason, it wouldn’t be human nature. That fellow, if he covets the stone at all, will want it for himself. If he makes public what he knows, the stone will go to the chief. He has every reason for saying nothing.”

“Humph! I dunno but what that’s so. I reckon Injuns ain’t a heap different from other folks when it comes down to diamonds.”

“Especially in this case. I imagine from the fact that these stones were found in the canoe with the idol that they have some special significance. The thieves who took the idol must have found the stones not far from it, for it is not reasonable to suppose that having attempted such a daring feat they would waste much time in hunting for other booty.”

“Wa’al, that does sound reasonable,” admitted the captain. “I wish that chap would come back. I’d like to ‘parlez-vous’ a bit with him, or rather ‘habla Espanol,’ although it does puzzle a Christian to make out whether he’s talking Spanish or Chinee.”

Darkness came on and there was no sign of the reappearance of the interpreter. But nobody else had disturbed them, which appeared to confirm Mr. Chadwick’s theory that the man would keep his discovery to himself. It was probably some four hours after darkness had fallen that a whisper was borne to them from above.

“Se?or Capitan!” came the voice in low, cautious tones.

“That’s red-jacket for a million,” declared the skipper.

“Hullo,” he responded, “what do you want?”

From this point on, the conversation was in Spanish. But the captain’s frequent asides enabled the listeners to keep track of what was said. Not to detail the worthy skipper’s remarks, he informed his companions that “red-jacket,” as he called the interpreter, was prepared to lower a rope ladder and escort them to their machine, which he declared to be uninjured, if they on their part would give him the diamond.

As Mr. Chadwick had guessed, the stone had a religious significance. From what “red-jacket” said, it was one of six such stones, the possession of which proclaimed their owners the high-priests of the ugly idol. The state of Chekla’s kingdom was restless. There was a sort of movement against the priests; but the interpreter thought that if he could get possession of the diamond he would be able to gain great ascendency in his country, and possibly become the next ruler in case Chekla was overthrown. At any rate, they didn’t bother much over his reasons for wanting the diamond. All they knew was that he was willing to barter their liberty for it, and that he appeared to have no idea that they still retained the other five stones.

“He says that if we’ll give him the stone, he’ll be here some time during the night with a rope ladder,” said the captain.

“Do you think he’s to be trusted?” asked Mr. Chadwick.

“Well, it’s just this way,” was the response. “If we give him the diamond and he doesn’t make good, we are no worse off than we were before. On the other hand, I think we can trust him. For one thing, he’s convinced that the diamond has something to do with that idol, and probably figures that the idol would fix him if he tried any funny business.”

“That sounds reasonable,” said Mr. Chadwick. “What do you think, boys?”

“I’d give him a peck of ‘em to get out of here,” declared Tom—a sentiment which the others heartily endorsed. The diamonds were as so much dross to them beside their liberty.

The captain spoke a few words rapidly to the unseen figure at the lattice and soon a long string made of a grape vine came snaking down. It had a lump of pitch or rubber at the end, and in this the captain embedded what was, without doubt, one of the finest diamonds in the world.

“Talk about castin’ pearls before swine,” he growled as the rope was drawn upward. “But then it’s worth it. Yes, by Jim Hill, if he makes good, it’s worth it.”

The next few hours were passed in what can only be described as an agony of suspense. The chances that “red-jacket” would play them false seemed to overwhelmingly outweigh the possibilities of his making good on his word. As the time dragged slowly by, they declared again and again that they had been fooled into giving up the stone, and despair came near overmastering the younger members of the party.

But just when it appeared impossible that they could endure the suspense a minute longer, they heard the lattice-work grating being moved. Through the opening they could see the stars, and then came a rustling, grating sound and the lower end of a ladder, formed from twisted creepers, with iron-wood rungs dropped amongst them.
CHAPTER XXVII. THE PROFESSOR TRIUMPHS.
Within ten minutes the last of them had mounted the ladder and gained the open night. All about them the huts of the village showed blackly in the starlight. They soon perceived that they stood at some distance from the central stone building, and that their place of captivity had been underground as they had surmised.

But although they had escaped from their prison they were still in fearful danger. Even as they waited there, a tall form, that of a sentry, strode around the corner of the building. In two bounds “red-jacket” was on him. He must have been possessed of huge strength, for the fellow went down like a nine-pin with the interpreter on top of him. When the latter arose the sentry lay quite still.

“You ain’t killed him, have you?” asked the captain as the interpreter rejoined the group.

“He says that if he has, it’ll be blamed on us,” the captain translated to his companions when the interpreter had whispered his reply.

“That’s fine,” muttered Tom; “a good beginning I must say.”

But their guardian was motioning to them to follow him. He had replaced the grating and concealed the rope ladder in some brush and rocks that grew near by. As they silently crept after their guide down a street of huts, they were all conscious of choking heart-beats and pulses that throbbed with uncomfortable rapidity. The slightest false step might bring the whole village down on them.

In this way they reached the end of the street and saw before them something that made them choke with delight. It was the huge, bulking outline of the Wondership. There she stood, seemingly as safe and sound as when they had left her.

With a whispered word to the captain that he had done all he dared, their guide left them here and slipped off among the shadows.

“The game is in our own hands now,” whispered the captain as they crept forward. “Go as silent as cats and we’re all right.”

On tip-toe, hardly daring to draw breath, they crept on toward the Wondership. It was like carrying a lighted torch above a pit full of dynamite. At any instant an explosion that would prove fatal to them all was liable to happen.

And suddenly it did.

As ill-luck would have it, one of Chekla’s subjects, either for hygienic or other reasons, had chosen to sleep out of doors that night. Tom’s foot struck him in the ribs, and with a yell that might have been heard a mile off the man sprang to his feet. Shouting at the top of his voice, he made for the village.

“Wow-ow! Now the fat’s in the fire!” gasped the skipper aghast at this unforeseen calamity. “Jack, if you can’t git that craft inter the air in five seconds or less, we’re gone coons!”

They set off on a run for the craft. All attempt at secrecy was useless now. It was simply a race against time. From the aroused village came a perfect babel of yells and shouts. Lights flashed. Savage imprecations resounded. The whole place was astir like a disturbed bee-hive.

Into the machine they tumbled helter-skelter. Jack switched on one of the shaded lights, pulled a lever and the welcome chug-chug of the gas pump responded. The Wondership swayed and pitched.

“Let ‘er go!” shouted the captain as from the village a mass of yelling savages came rushing down on them.

“Hold on!” shouted the young commander of the flying auto. “Where’s Tom?”

“Great Scott! Ain’t he here?”

“No!”

“Good Lord!” groaned the captain. “It’s all off now!”

But out of the darkness came a shout. It was Tom.

“Hold on. I’ll be with you.”

Then came the sounds of a struggle and the next instant they heard the impact of a crunching blow, a yell of pain and a savage shout, “Take that!”

“That’s Tom in action,” shouted the captain. “Come on, Tom!”

There was a rush of feet and the boy came bounding out of the darkness.

“Got lost in the shuffle!” he gasped.

“That’s all right,” shouted Mr. Chadwick, grabbing him; “in with you, boy, quick!”

In tumbled Tom, half climbing and half-dragged. He lay on the floor in a panting heap, while Jack swiftly raised the panels. This time they worked, and they found out afterward that the temporary sticking that had proved so disastrous was caused by the expansion of the metal in the hot sun.

He was not an instant too soon. Hardly had the plates clanged together with a metallic clash before the savages were on them. Captain Sprowl opened a port in the “whaleback” superstructure and poured out a murderous fire on the Indians before he could be checked.

“Warm work!” he cried, pumping away at the mechanism of the rifle.

From without, came yells and screams. Spears, darts and stones crashed against the machine as if they would smash it to atoms. But in the midst of the turmoil the fugitives felt a sudden upward lurch. So sudden was it that they were all hurled into a heap. But they cared but little for that. The Wondership was going up, bearing them aloft to safety!

As she shot upward, her machinery whirring bravely above the yells and confusion below, Captain Sprowl turned to the others.

“A good Yankee cheer, boys!” he said.

In the deafening din that followed, the professor’s voice was heard ringing out as loudly as any of them. It was the professor, too, who cried out at the conclusion:

“Undt ein Tiger!”

But perhaps the cheers had been a little premature. It was getting toward dawn when it became apparent to all on board that the Wondership was not behaving properly. Her engines revolved more and more slowly. She began to make long swoops and dips.

“What in the world ails her?” demanded the captain.

“Don’t know,” rejoined Jack; “might be any one of a dozen things. We’ll have to go down to fix her.”

“But it’s dark. You can’t land in the tree tops,” expostulated Mr. Chadwick.

“I know that. I think I can manage to keep her going till daylight. If not, we must take our chances.”

Soon after, the first pale light of dawn dimmed the stars. Beneath them—they were heading due east—showed a river. By this time the craft was almost without motion, although, of course, there was no fear of her dropping, for her gas-bag supported her. But the wind was east, and every minute that the engine remained idle, they were being carried back toward the land of the tribe from which they had effected their escape.

With what power remained, Jack brought the Wondership to rest on the surface of the river. She was at once made fast to the bank and the two boys set to work on the engines. It did not take long to locate the trouble. The air intake, by which a certain amount of air was mixed with the explosive gas, had become clogged. To clean it out and put it in good shape would have taken quite a time. Under the circumstances they decided to have breakfast first and then get to work. During the meal a bright lookout was kept and they ate cold stuff, not knowing what hostile tribes might be about and not daring to light a fire.

It was toward the close of the meal that they were considerably startled by loud shouts from a point not far distant. They came rapidly nearer.

“Indians!” gasped Tom.

The rifles were brought from the machine and they awaited the oncoming of the natives with grim determination. But the yells were soon perceived to be those of terror rather than ferocity. As they came closer, Captain Sprowl spoke with an air of authority.

“Those fellows, whoever they are, are running away from something or somebody,” he said.

“May be a tribal war,” suggested Mr. Chadwick.

“Maybe. But hark, what in the ‘Tarnal is that?”

Upon the wind there came, loud above the Indians’ shrieks and cries, a long-drawn noise like a yapping bark.

“Sounds like wolves!” cried Jack.

He had hardly spoken before through the woods, a short distance below them, a number of Indians burst upon the river bank. They piled into some canoes that the adventurers had not perceived hitherto but which had been lying on the bank. Entering them they paddled off down the stream in mad haste, as if in mortal fear of whatever was pursuing them.

The party were still watching them when again that queer bark resounded, and from the forest, at just the point where the canoes had lain, there burst an enormous animal, the like of which none of them had ever beheld.
At the same instant, Jack’s rifle cracked.—Page 297.

It was larger than a big cow and ran with a queer, romping sort of gait, suggestive of a rocking horse. Its head was flat and hideous. Its color a dirty brownish white. A more repulsive looking creature could hardly be imagined.

As his eyes fell on it, the professor gave a gasp. He shook from head to foot as if he had been suddenly taken with a fit of the ague.

“Mein Gott in Himmel!” he gasped, and there was no irreverence in his tone, “Der Megatherium!”

At the same instant, Jack’s rifle cracked. The creature gave a loud, terribly human scream and swung toward them. Tom’s rifle barked and with a crash the huge animal sank down in a heap on the river bank. They rushed pell-mell upon it. The professor was yelling like a wild man. The others were hardly less excited.

“Be careful,” warned Mr. Chadwick, as they approached, but the animal was quite dead.

It lay on its side with its legs outstretched. On its feet were large curved claws and its hair was as rough and coarse as that of the small sloth they had shot some days before. As they stood by it, gazing with a wonder in which there was something reverential at this survivor of the age of the mammoth, the professor spoke.

“Chentlemen, ve are der only living beings besides de savages dot haf efer seen such a sighdt. Poys! Der contracdt is ge-fulfilled!”

“Mumping mammoths of Mauretania, I’ll take a picture!” shouted Dick Donovan by a happy inspiration. And there, by the side of that lonely river, was taken the photo that has since been reproduced in countless periodicals throughout the world.

And here, as you may easily guess, the adventures of the Boy Inventors in Brazil practically came to an end. Soon after the discovery of the giant sloth—which was a young and not fully grown specimen—the engine was put in order and the trip to the coast resumed. Of course the entire carcass was taken, in spite of the extra weight which the Wondership bore bravely. Every hair of the beast was precious in the professor’s estimation. When the camp was reached (where they found Judkins peaceably awaiting their return, and very much better) the carcass was skinned, and the flesh boiled from the bones, which were later articulated.

After a day or two in the camp, to allow the professor time to complete his work, they all set sail for the nearest town, Bahia de Santos, five hundred miles to the north. With the discovery of the giant sloth, even though it was not an adult specimen, the professor’s task of proving that such creatures still roam the earth, was completed.

In Bahia de Santos they found a small fruit steamer bound for New Orleans. An arrangement was soon made by which they were accepted as passengers and the Wondership, that had done them such good service, traveled as freight on the steamer’s deck.

There was a wireless telegraph at Bahia, and this was kept hot for a time conveying to friends news of their safety and of the professor’s great discovery. At Bahia, too, they learned that both the boat-loads of mutineers had been picked up a short way down the coast, and, with a luck they ill deserved, they had all managed to find berths on different ships and were scattered far beyond the reach of the authorities. As the Valkyrie was amply insured, the professor had no desire to pursue them and there the matter rested.

As to the diamonds, they fetched a surprising price in the States, and the boys decided to employ their share of them in constructing a new invention with which they seem destined to have some astonishing adventures. What this new invention of the ingenious lads proved to be, and how they used it, must be saved for the telling in another volume.

Judkins was suitably recompensed and a good job was found for him on a steamship line in which Mr. Chadwick happened to be interested. Captain Sprowl was made independent by his share of the diamonds. As for Dick Donovan, his story of the finding of the Giant Sloth made him famous overnight. He now commands a big salary, but nothing so exciting as his trip to the Amazon country has engaged his attentions since. He and the boys have become fast friends and he is a frequent visitor to High Towers.

And now we will say “Good-bye” to the Boy Inventors, wishing them well till we meet them again in the next book to be devoted to their doings.

The End