"Aft there—aft and dip your colors!" shouted Bluewater Bill.

Ben Stubbs scrambled to the stern and dipped the flag again and again as the big black craft rushed on, without, however, noticing the courtesy of the small boat. As she sped by the boys spied her name, Brazos, in big gilt letters on her stern.

"I wish we could go as fast as that," remarked Billy, as the big steamer rapidly dwindled and finally passed out of sight, leaving only a black pall of smoke to show that she had passed.

"We are doing well enough," remarked Bluewater Bill, gazing back at the Bolo's wake.

"What are we making, do you judge?" asked Frank.

"Ten knots easily," replied the sailor, squinting at the white line of foam astern.

"Pretty good for this little craft," remarked Ben Stubbs, "though you can't always judge by the wake. I remember when I was on the old Dolphin brigantine in the China Sea. One morning we all of a sudden noticed a most termendous wake ahind us. It was running like a mill-race. I peeked over the side and it was fair whooping along.

"Why, we must be going twenty miles an hour," says the skipper; "queer we can't feel any motion."

"Well, boys, to make a long story short, we was that way for three days and never moved a foot. You see, it was one of them queer currents, and the pace it streaked by made it look as though we was going ahead when, shiver my top-gallants, if we wasn't standing still, the wind being just strong enough to keep us going forward at the same pace the current drew us back—what do you think of that?"

The boys didn't know what to think, and said so, but Bluewater Bill winked at them with a portentous eye and merely said:

"That reminds me, shipmate, of what happened when I was aboard the Flying Scud off Madagascar. If so be you don't mind, I'll spin you the yarn.

"One night it comes on to blow most tremenjous, and by morning we finds we was in one of them circular storms. Wall, mates, the wind blew all around us, but we didn't move at all. At eight bells the pig-pen fetched loose and them porkers got caught in the wind and whisked off the deck by the hurricane. As I've said, it was a circular storm and them poor porkers jest kep a goin' roun' and roun' and roun' the ship all that day. It was night afore the wind died down, and then, by a freak, it reversed and blew 'em all back again; but they was so dizzy that for a week they ran round the deck in circles and when we wanted pork it was no trick at all to catch a hog. All you had to do was to find out how he was revolving and then get in his way,—what do you think of that?"

"That you are exaggerating, William," said Ben, in a tone of reproof.

"Wall, if wind and tide can hold a ship still; wind alone can give a bunch of hogs a merry-go-round, can't it?" rejoined Bill.

"It can, but it don't," was Ben's reply.

"Ah, but you never sailed off the coast of Madagascar, did yer?" demanded Bill.

"No, I can't say as I ever did," replied Ben.

"Wall, then," triumphantly cried Bill, "you don't know what a pesky wind that Madagascar one is."

How long this argument, which the boys listened to with some amusement, might have gone on is hard to say, probably all night, if Ben had not suddenly cut it short by springing to his feet with an exclamation:

"Come on, shipmates!" he exclaimed, "stop gamming and get a move on and snug down this yer awning if you don't want to lose it. Billy, you open the self-baling scuppers in the cockpit, my lad, and Lathrop and Harry, you get out forward and double lash all that top hamper."

"Why, Ben, what's the matter?" asked Frank, "the sea is just as smooth as it has been all day and the sun is shining."

"Well, it won't be in a half an hour," replied the old salt, pointing southward. "See that cloud?"

He indicated a tiny purplish bit of vapor floating against the distant blue like an argosy. "There's wind in that cloud or my name's not Ben Stubbs," he concluded.

Bluewater Bill nodded his assent.

"Mor'n a capful, too," he said grimly.

Even as the two old salts exchanged glances the cloud seemed to grow, as if by magic, and by the time the awning was snugged home and lashed and everything had been hauled taut in preparation for the blow, the whole heavens were overcast with a sullen gray veil, and the sea began to rise with a low moaning sound that presaged what Ben Stubbs termed "a bad blow."



CHAPTER XVI.

IN DIRE PERIL.

"Get that thar dory aboard," was Ben's next order to the boys, who began to feel quite tired, what with their exertions and the oppressive weather. As he spoke, a livid streak of lightning tore across the overcast sky, followed by a long roll of thunder that made the boat vibrate.

"Come on, bear a hand, there's no time to lose," he insisted, "tumble aft there—tumble aft."

It was quite a task to get the dory aboard, even with the aid of the Bolo's stern davits. The sea was rising every minute and even when they had the "falls," as they are called, secured to the little dinghy, she threatened to stave either herself or the Bolo while she was being hoisted and lashed. At last, however, even that task was accomplished and the boys began to anticipate a rest. But the indefatigable Ben would not let them loaf, even then.

"I want her to set more by the stern," he said, "shift those gasolene cans aft here, and we will trim her down in good shape."

"You see," he explained to Frank, "when the sea gets real high she's going to lift her propeller out of the water if she isn't well down by the stern, and that would make the engine 'race,' and that we don't want it to do, as it is likely to put it out of business."

The boy nodded.

"I suppose it's a good thing to have all the freeboard at the bow you can, also," he said.

"That's the idea," was Ben's reply.

And now the storm was upon them in its full fury.

The wind seemed like a wild beast filled with furious instincts and bent on the destruction of the Bolo. Half buried in the giant waves that the sudden hurricane whipped up, the little craft bravely struggled along. Bluewater Bill kept her nose pointed right into the big combers.

Her engine was cut down to half and then a quarter speed, but she was rolling so badly that Ben Stubbs was considering the advisability of putting a rag of sail on her to steady her. She wallowed in the big seas like an empty bottle, and every lurch threatened to start some of her seams.

While not exactly scared, the boys were certainly worried.

"Do you think she'll last out?" asked Billy of Ben, poking his head out of the cabin companion—for all the boys but Frank had been ordered below by Ben that there might be plenty of room for working the Bolo in case of a sudden emergency.

"Last out?" roared Ben, the wind whipping the words from his lips as fast as he framed them, "why of course she will, my boy. I've seen as bad seas as this lived out by a craft no bigger than our dory."

But although Ben spoke so confidently he was, none the less, worried. As long as the engine kept at its work he knew they were all right, but, like most old "tar hands," he mistrusted gasolene "contraptions," as he called them, and in this instance his mistrust seemed well founded, for, as he stood in the after part of the cockpit looking anxiously astern at the mountainous green combers that raced after the Bolo, as if determined to drag her down to "Davy Jones' locker," the old sailor noticed something peculiar about the motion of the boat.

She seemed to be falling off into the trough of the waves.

"Keep her up!" yelled Ben to Bluewater Bill, who sat grimly at the wheel affixed to the cabin bulkhead.

"I can't!" roared back Bill against the fury of the wind.

"What's the matter?"

"The engine's broke down, I guess; anyhow, she don't answer her helm, I can't get steerageway on her."

As he spoke a huge sea crashed broadside on against the Bolo, shaking her as an angry mother shakes a child, and sending a great volume of green water tumbling aboard.

"We've got to do something and do it quick or we'll be swamped," thought Ben to himself.

He banged on the top of the closed companion slide.

It was drawn back from inside and Harry's head appeared.

"Did we strike anything, Ben?" he asked.

"No, youngster, but a wave struck us and that's near as bad. What's the matter with the engine?"

"I don't know," answered the boy, "I'm trying to fix it, but the boat's rolling so that I can't seem to get at anything. I'm doing the best I can."

"Well, fix it as quick as you can," was Ben's reply.

"Why—are we in danger?" demanded Harry, struck by Ben's anxious tone.

"Well, I don't want to say that YET, but we've got to get out of the trough of the sea or—"

A huge wave came toppling aboard, drenching the speaker from top to toe, and almost washing him overboard. A brass handhold saved him. The cockpit was instantly flooded, but thanks to the patent self-baling scuppers, she cleared herself without much water getting into the cabin.

But it had been a narrow escape for all three of the adventurers in the open part of the boat. As the mass of water struck him, Frank had grabbed an awning stanchion, more from instinct than anything else, and thus saved himself from being swept overboard.

Bill had laid hold of the wheel, and although he was lifted from the helmsman's seat and forcibly banged down again, he was safe.

"We've got to rig a sea anchor," declared Ben, "but in the first place, Frank, get below and empty your canvas clothes bags, stuff 'em with oakum and pour all the lubricating oil you can spare in on top of the oakum and then make a lot of holes in the side with your knife."

Frank did not ask any questions, although he had no idea what the old sailor meant to do. He entered the cabin, through the slide, and was soon at work on his assigned task, although the motion of the Bolo, which seemed first to stand on her bow and then on her stern and varied this with a plunge sideways till it seemed as if she was going to the bottom, made its accomplishment difficult.

In the meantime, Ben had taken the oars and spare spar out of the dory and lashed them all together with a long rope. Carrying this bundle forward he attached it to a line and dropped it overboard. The Bolo instantly began to drift away from it as it seemed. Soon there was a distance of fifty feet or more between the struggling vessel's bow and this improvised "sea-anchor." Ben made the line fast to a Samson post and crawled aft along the cabin roof; pausing several times when an extra hard blast of wind made it dangerous to proceed.

Primitive as the device was, it answered.

The Bolo's head was drawn round toward the wind by this "drag," as sailors call it, and she no longer shipped cross seas. A few minutes later, Frank had two of the oil bags ordered by Ben ready. Once more the sailor crawled on to the plunging bow and made one of the devices fast on either side.

To Frank's amazement the seas at once began to subside—that is, in the immediate vicinity of the Bolo.

"That's what oil will do," commented Ben, gazing about him with a satisfied look. "It spreads a thin scum on the waves and prevents them breaking. Now we shall do nicely for awhile, though now the worst is about over, I don't mind admitting that I did think once or twice that we were bound for Davy Jones' locker."

After a lot of searching the cause of the engine's sudden stoppage was located. One of the bearings had become so heated in the struggle against the storm that the machine had ceased working. The cause was evidently that the violent "tumblefication" that the Bolo had gone through had hindered the proper operation of the force-feed lubrication. After giving the bearing time to cool off, Frank affixed a regular grease cup to it and no difficulty was then experienced in starting up the engine once more.

"No use in laying to," said Ben, after he had been consulted as to the advisability of going ahead. "The blow's as bad now as it will get, and we are being driven back every minute we aren't going forward. There's no such thing at sea as standing still."

The drag was accordingly hauled aboard, at no small risk; but the oil bags were left to drip their calming lubricant alongside. This done, the Bolo was put on her course again and slowly forced her way through and over the angry waves that seemed determined to prevent her progress. Owing to the heavy clouds that overhung the sky, ever and anon ripped open by a lightning flash, it grew dark at four o'clock, or eight bells, as Ben called it, and Bluewater Bill was sent forward with the lights. But they had hardly been placed in position when a huge sea swept the Bolo from stem to stern, extinguishing them instantly.

"No use putting out any more," said Ben, "we must trust to luck not to run across any vessels. I don't think that we are in the steamer track anyway."

But how wrong Ben's words were they all realized when, at about midnight, Harry, who had the wheel, thundered on the cabin top and yelled at the top of his voice:

"All hands on deck."

They tumbled out without waiting to don any more clothes than they had turned in with. The cause of the boy's sudden summons was at once plain. Not half a mile from them were the red and green lights of an approaching steamer, and judging from the height they were out above the water, the vessel was a big one.

"She's headed right for us," shouted Harry.

"That's right, we can see both lights," exclaimed Frank.

"Put your wheel over," yelled Ben.

"I can't, something's the matter with it," rejoined Harry, as the Bolo rose on the crest of another big wave and they saw the steamer driving toward them right in their path.

"Tiller rope's broken," pronounced Frank after a brief examination.

"No time to fix it up now," announced Ben, "cut out the engine. We must trust to the wind to drift us off the steamer's course."

Bluewater Bill dived into the cabin for the lantern, but the furious wind snuffed out the light in a second.

And all the time the big steamer was driving closer and closer—straight for the helpless motor-boat.

"The signal gun," suddenly shouted Frank. This was a small saluting cannon fixed to the after end of the cabin roof.

Quick as thought Billy and Lathrop ripped off the waterproof cover and Frank jerked the lanyard. Luckily the gun had been loaded with the idea of firing salutes as they left Galveston, but the idea had been forgotten in the excitement.

"Bang!"

Even above the storm the report sounded loudly, and the flash at least was visible.

Would the steamer notice their signal?

There was a moment of agonizing suspense—in which the boys saw death at sea in its ugliest form loom up in front of them.



The towering black bows seemed to be imminent above the Bolo when there was a sudden flashing of lights on the lofty foredeck, and a voice hailed through the night:

"Motor-boat ahoy!"

The adventurers shouted back at the top of their lungs.

Suddenly the black form of the great vessel, pierced by scores of lighted portholes, seemed to glide away from the Bolo, and, with a rush and roar as the waves smashed against her lofty steel sides, the big vessel raced by.

Gazing far above them the boys could see a uniformed figure on the bridge shouting questions through a megaphone. He was, no doubt, inquiring what sort of lunatics they were whom he had so narrowly escaped sending to the bottom.

"A miss is as good as a mile," was Ben's comment when they all breathed more freely, "but no more misses like that, thank you."



CHAPTER XVII.

BILLY'S NARROW ESCAPE.

By daybreak the fury of the hurricane had blown itself out and the sun rose on a sea that while still storm-tossed was moderate compared to the terrific upheaval of the preceding night; by noon, in fact, so suddenly did the wind drop, the Bolo was nosing her way along through what seemed a glittering, sunlit desert of almost perfectly smooth water.

"Let's get the lines out and troll; we might catch a shark," was Billy's sudden suggestion.

"Right you are," assented Bluewater Bill. "There's lots of them in these waters—savage critters, too. It's a charity to catch them."

Suddenly he broke into song:

"Oh, sharks have teeth and whales have tails, Cows have horns and so have snails, But of all the fish in the ocean blue The very worst is the green gaboo."

"What on earth is a gaboo?" demanded Frank, who with the others was lolling about the cockpit under the awning, which had been re-rigged.

"Why," said Bill, scratching his head, "a gaboo is—well now, let's see—ah, yes, a gaboo is a good rhyme for blue."

"If you do anything like that again we shall have to hold a court-martial and have you thrown overboard to feed your gaboos," laughed Frank.

"Well, that's what you call poetic license," protested Bill.

"From now on, yours is revoked," declared Frank, "but, seriously, Bill, do you know anything about shark fishing?"

"Do I?" demanded the old shellback. "Well, when I was in these very waters in the Scaramouch we caught one with a bit of pork that weighed—the shark, I mean, not the pork—I forget just what, and wouldn't say, for fear you might think I was prevastigating, but it was twenty-four foot long."

"Oh, come, Bill, not twenty-four," protested Harry.

"That's what it was," stoutly asserted Bill, rummaging in a locker for a shark-hook.

"Why, the biggest shark recorded is only eighteen feet in length," protested Billy.

"Don't know nothing 'bout records, Master Billy, but I do know that this yar varmint was twenty-four."

"Did you measure him?" asked Frank.

"Not much," snorted Bill, "he'd have measured us, and we'd have soon measured our length if we'd tried. But now if any one has a bit of fat pork, I wouldn't be a bit surprised but we can fish up one of them finny monsters."

Accordingly a bit of pork was secured from the galley stores and placed on the shark-hook, a huge affair as big as the hook used to hang meat on in butcher shops. To its hank was shackled a bit of stout chain, about two feet long. To this, Bill affixed a stout rope, and let the line trail out astern about fifty feet.

"Now, Billy Barnes, since you was so skeptical, you hold the line, and, when you feel a tug, take a turn around the cleat here or he'll yank you overboard."

"Yank me overboard," cried Billy, incredulously. "Oh, get out, Bill! What do you think I am—an old woman?"

Bill said nothing, but cut himself a big bit of chewing tobacco and stuffed it into his face. Frank would not have allowed such a habit on the Bolo, but he felt as he had deprived the old sailors of their pipes, he could not cut off every luxury, so Bill was allowed to chew in quiet content.

"Isn't this bully, just going right ahead like this after all the terrible things that happened in the night!" exclaimed Harry, as the Bolo cut along through the placid waters.

"Great," agreed Frank, "and yet I am glad in one way we ran into that blow. Ben Stubbs assured me that we were not likely to get anything worse in these latitudes, and the Bolo stood up to it as if she had been a clipper."

"Yes; she certainly is a fine little ship," agreed the others.

All at once there came a yell from Billy Barnes.

The startled boys look up just in time to see him yanked bodily out of the cockpit, over the counter and into the sea. To their horror, when he struck the water he vanished; only to reappear a few seconds later, however, with his head above the surface, and moving through the water away from the boat at a terrific rate.

"Good heavens, what has happened!" exclaimed Frank, horror-struck at the scene. The others were white and too unnerved at the sudden accident to speak.

Only Bill and Ben Stubbs kept their heads.

"Let go of the rope," they bellowed.

Billy gave a despairing look back and then was rushed onward through the water at a greater speed than ever.

"What is it—what has happened?" repeated Frank.

"Matter enough," was Ben's rejoinder, "he has evidently got that shark line entangled in his clothing and when the monster gave a pull at the hook it yanked him overboard."

"What are we to do?" cried Harry.

"Put on full speed and go about," cried Ben, suiting the action to the word.

At top speed the Bolo rushed through the water after poor Billy, who was still being borne along at a terrific rate by the hooked shark.

"Get ready to shoot the shark when he comes up," yelled Ben.

"But will he come up?" asked Frank.

"He's got to," was Ben's brief reply, "with that hook in him, he's as good as dead. He won't keep under much longer now."

"Hold up, Billy," shouted the boys to their imperiled companion, but the young reporter was too far gone and too choked with the water he had swallowed in trying to keep his head above water to reply.

Frank dived into the cabin and reappeared with a heavy rifle. He slipped into it a cartridge carrying an explosive bullet. Trembling with eagerness, he took up his position on the bow of the speeding Bolo, anxiously scanning the waters ahead for any sign of the shark's reappearance.

Suddenly an ugly black fin loomed up, cutting through the water like the conning tower of a submarine.

"Crack!"

The explosive bullet sped from the rifle, but either Frank's aim was bad from nervousness or the powder charge was too heavy, the ball struck the water fully a foot from the racing creature.

"Try again," said Ben consolingly, "I'll slow down the boat."

Luckily the shark had not dived and his fin still afforded a good mark. It was moving so rapidly, however, that it was going to be a difficult matter to hit the large body that moved beneath it.

Once more Frank rested the rifle and drew a careful sight on the fin. He aimed a little ahead of it this time, with the result that there was a terrific disturbance of the waters as the bullet sped home and the wounded creature convulsed with the pain.

"Another," cried Ben; "good work."

Before Frank could fit another cartridge—his rifle was a single-chambered one—the shark had dived, leaving only a crimsoned pool on the smooth surface to bear testimony that he was wounded.

The boys uttered a groan of dismay as they saw the thrashing form vanish and a second later saw Billy flash out of view.

It seemed impossible that their chum could survive being dragged to the depths of the sea.

The shark, however, did not remain down long. It soon reappeared on the surface, with Billy in tow, still thrashing the water into crimson fountains with its fins and tail. Sometimes it leaped clear out of the water in its agony.

"Bang!"

Another bullet sped from Frank's rifle, and this time the maddened animal seemed to sense from whence came the attack, for it suddenly charged furiously at the motor-boat.

Quick as thought, Ben Stubbs, who had seen its coming, leaned over the side and with his seaman's knife in hand waited the moment when it dived under the boat.

As it did so he gave a quick downward slash.

The rope that seemed to be pulling Billy to his doom severed under the blade with a crack. The next minute the young reporter was able to swim feebly to the side of the Bolo.

Badly weakened and unnerved by his experience he was pulled on board and laid on a bunk in the cabin, where restoratives were administered to him.

It was late in the evening before he was himself again, and he then explained how he had been idly twisting the line in and out of a hook on his belt when there came a sudden tug. Before he knew what was happening he found himself rushing through the air and was then immersed. Fortunately, he was a good swimmer and kept his head or there might have been a more serious termination to his adventure.

"How big do you think that shark was, Billy Barnes?" Frank could not help asking him mischievously later in the evening.

"Oh, at least fifty feet," was the young reporter's reply, delivered in all seriousness.



CHAPTER XVIII.

INTO THE SARGASSO.

The days slipped rapidly by until one fine morning, about a week after the events narrated in our last chapter, Ben Stubbs and Frank announced that their observations showed that they had doubled the southernmost cape of Florida (which had been the scene of some earlier thrilling adventures described in the second volume of this series, "The Boy Aviators on Secret Service"), and were now on a direct course for the mysterious region of the Sargasso Sea. For three days more they went steadily onward toward the rising sun, occasionally sighting a school of porpoises and scaring up whole legions of flying-fish with their sharp bow. The days were glorious—a trifle hot, perhaps, but none of the boys minded that; and at night the stars, "as big as lamps," Billy declared they looked in the far southern latitude they had now reached, gave almost as much light as the moon in our chilly northern clime.

Every day, now, some one of the party took turns with the glasses under a small shelter erected with canvas and oars in the bow of the boat, and painstakingly scanned the horizon all about for any sight of the Brigand or Luther Barr's dirigible. But although once or twice they saw distant smoke, it always turned out to be a false alarm, and they hourly grew nearer the Sargasso without having made out a trace of the rival treasure-hunters. This fact put them all in high spirits, and each of the boys was already busy building lofty air-castles concerning what he would do with the treasure when he got it.

Much of the time, too, was occupied in clearing away the lashings of the planes and other apparatus and parts of the Golden Eagle attached to the cabin top forward, and discussing plans to erect her at sea. Frank perhaps was the only one of the party who fully realized the extreme difficulties that confronted them. However, the water was at present smooth as glass almost and seemed likely to remain so, if Bluewater Bill and Ben Stubbs were to be relied on as weather prophets.

"We are getting into the Doldrums now for fair," the old sailor announced one morning, pointing to the horizon, where a big, full-rigged vessel lay motionless in the breathless atmosphere. "That ship yonder may not get out of here for a week."

The chart now showed that they were far out of the track of all ships and on a lonely sea, so that the becalmed wind-jammer had probably been driven off her course in the same hurricane that menaced them and was likely to be a long time before she got out of her melancholy predicament.

One day Billy, who was leaning over the side, gave a sharp cry and drew back from the bulwarks.

"Come here, fellows—ugh, what an awful-looking thing," he cried.

He pointed down at the sea. The others rushed to his side, and as they gazed into the water, which was as clear as crystal for a considerable depth, they felt like echoing his exclamation of repulsion.

Through the opalescent green overside could be seen a huge shadowy shape slowly settling downward, though from the depth two menacing eyes gleamed upward at the young watchers.

From every side of the creature's round, barrel-like body stretched huge arms covered with myriads of suckers. It looked like some evil spirit of the deep, and the boys estimated the length of its arms as at least twenty-five feet. It slowly waved the long feelers as if in farewell as it sank.

"That there's a devil-fish," proclaimed Ben, who had joined the group as the monster vanished, "some calls 'em octopus, but devil-fish is a better word, to my thinking."

The boys agreed with him.

"Surely that must have been an unusually large one, Ben?" exclaimed Frank, still with the feeling of repulsion with which the monster had imbued him strong upon him.

"A big one," echoed Ben. "Oh, no, not so extra big—though he was sizeable, I'll admit. I've never seen such things myself, but I've heard crews of whalers tell of having been attacked by one of them critters, and sometimes they come back to the ship several men short. Them devil-fish are as ferocious as tigers and many's the poor sponge-diver they have gobbled up."

"Are there any in Sargasso Sea?" asked Billy, who seemed fascinated by the subject.

"I should say there are," put in Bluewater Bill, "and they grow there as big as elephants to a rabbit compared to this fellow. I don't doubt that some of them has lived there for hundreds of years, just like turtles. You see it's a fine place for feeding in, among all that seaweed, and when a ship gets in there and some poor chap goes crazy and jumps overboard, why, then they have an extra nice morsel to make 'em get fat and live long."

"Well, that's a nice prospect," said Billy. "I don't know but what I should prefer their room to their company."

"Same here," chorused the others.

Hour by hour now the seaweed began to get thicker. At first spread in isolated clumps and drifting prettily on the waves, it now became so dense as to be a menace.

"We'll have to turn back," announced Frank, "we can't afford to risk snarling up the propeller."

Accordingly the Bolo's head was put about and she was headed westward again. When the seaweed became so thin as to not offer any serious impediment to navigation, the Bolo's heavy anchor was dropped. Luckily she carried six hundred feet of one inch manila, but even this was hardly enough for the depth of water and had to be eked out with every bit of chain and cable that could be spared. Fortunately under the circumstances the Bolo carried a capstan which could be thrown into a gear with the engine, otherwise it would have been impossible for her to anchor in that depth of water, as her crew could never have got up the mud-hook by hand.

The weather promised to be clear, and a consultation of the barometer showed the instrument to be absolutely steady. After breakfast the next day, therefore, the work of erecting the Golden Eagle at sea was begun. First the pontoons were lowered over the side and the boys, working from the Bolo's dory, connected them by the rigid vanadium steel framework provided for that purpose, and which fitted into brackets bolted to the sides of the tubes themselves. When connected up they formed a sort of catamaran with a space of about twenty-five feet intervening between them. The chassis of the Golden Eagle, which was in sections, was then erected on a framework previously built and which was attached to the floating pontoons. This work occupied the greater part of two days, and impatient as Frank was to be off, he would not allow it to be slighted.



The wing-supporting framework rising from the chassis next engaged the young workmen's attention, each part being screwed to the other and fixed in place with nuts locked by a spring devised for the purpose by Frank. This was necessary, as the incessant jarring of an aeroplane's powerful engines will work loose the most tightly screwed on nut if it is not locked, and, of course, the working loose of even a minor part on an air craft is a serious proposition indeed. The vanadium steel quadrangle being in place, the next task was to adjust the wide stretching wing-frames of the big plane. This was a tough job, but the boys managed to overcome the tendency of the floating craft to capsize under the uneven burden by placing a raft made of boards from the cabin floor of the Bolo under each wing tip as it was screwed in place.

Of course, as soon as the frames were bolted on on either side and the weight was equalized, the aeroplane balanced on her pontoons and there was no need for artificial support. Getting the engine in place came next, and for a time seemed to promise serious difficulties; but this problem was finally solved by towing the pontoon-supported air-ship alongside the Bolo, and then using her main boom as a derrick. Billy Lathrop and Ben Stubbs hauled on a tackle attached to the engine, and thence to the end of the boom, and the heavy bit of machinery swung outboard without a hitch. It was then an easy matter to lower the motor on to its bed, which had been previously set in place. It didn't take long to bolt the engine down, lay the propeller bearings and set the main shaft and its twin connections in place and "true" them up. The last work, before adjusting the tanks for gasolene and oil, was to affix the propellers themselves. This was accomplished by erecting a rough stand on a platform of the cabin floor boards.

At last everything was pronounced ready for a start and the finishing touches were completed. Harry even lovingly touched up some scratched places about the frame with the contents of a paint-pot he had found in a locker.

It was at this point that Billy Barnes made a great discovery.

"But say, Frank," he exclaimed, "when you start the propellers she is going to fly even though you may want her to skim the water."

"Is she, mister know-it-all?" laughed Frank, "that shows all you know. See this pump?" He indicated a small centrifugal affair geared to the main shaft.

Billy nodded.

"Well," explained Frank, "when we want to keep the Golden Eagle down on earth, or rather sea, we fill the pontoon tanks to the necessary weight with this pump. When I want to rise, I pump the water out again."

"Gee, that's simple—like all your ideas, Frank," said the admiring Billy.

"When are we going to try a trial trip?" demanded Lathrop.

"No reason why we shouldn't start right away on one," declared Frank, "if you fellows will bear a hand and fill up the gasolene, radiator and lubricator tanks."

The receptacles were quickly replenished with fuel, water and oil, and then the young aviators waited in a thrilling state of suspense while Frank tested the engine. After a few adjustments of the bed, the machine fell to work as evenly as it had at Mineola, and Frank announced that he was ready to cast off the lines that restrained the aeroplane to the side of the Bolo.

With Frank in the driving seat, Harry at the engines and the others grouped in the chassis the start was made.

At Harry's cry of "All right," the young leader started up the power and threw in the propeller clutch. A shout broke from the throats of the adventurers as the Golden Eagle began to move gracefully ahead in her new element.

Soon she began to gather speed and skim rapidly over the water as Frank increased the power; but he soon came to a stop.

"We'll have to put more water in the tanks," he announced, "she's trying to rise."

More water was quickly pumped in by running the machine pump on the engine with the propellers cut out. As the ship settled lower and lower, Frank watched her carefully.

"That's enough," he cried at length to Harry, who was filling the tanks. The pump was stopped and the automatic caps screwed on the valve opening of the pontoons.

Once more Frank threw in the propeller clutch and started up the engine. This time he ran the motor to high speed without the aeroplane rising more than enough to just gracefully skim the top of the water, like a drinking swallow.

"It's better than flying," enthusiastically cried Billy, hugging Lathrop in his excitement, "and you don't have to keep still either," he added.

"Wall, I've followed the water for a good many years, but I never went to sea on a water air-ship before," was Bluewater Bill's contribution.

"You like it, don't you?" demanded Billy, almost fiercely.

"You bet cher life, I do," was Bill's truthful, if vulgarly expressed, rejoinder.

On and on skimmed the Golden Eagle, seemingly as much at home on the surface of the gently heaving South Atlantic as in the upper air currents. So exhilarating was the sensation, that Frank kept the winged craft straight on, holding her to her course with the air rudder, which worked as well on the water as in the clouds.

Then swinging in a long circle, so that the strain on the long pontoons and their bracings would not be too great, he brought the ship about and headed her back for the Bolo, that lay, a tiny speck, on the far horizon, so far and fast had they traveled.

They came back at the same swift gait as they had taken the outward spin, and all voted this new form of water riding as enjoyable as anything they had ever experienced.

That night was spent in making final arrangements for the dash in search of the golden galleon. As the adventurers did not want to carry more weight than could be avoided, it was agreed that Bluewater Bill, Lathrop and Billy Barnes should remain on board the Bolo, while the Boy Aviators and Ben Stubbs started on the aerial search for the treasure ship.

From the latitude and longitude in which they were then anchored, Bluewater Bill judged that the galleon could not lie much more than two hundred miles to the southeast, out across the wilderness of Sargasso. Of course she might have shifted, but from an aeroplane it is possible to survey a tremendous area, and the young adventurers were confident of being able to pick up the prize.

Two more bitterly disappointed youths than Billy and Lathrop could hardly be imagined than they were when they learned that it would be impossible to take them on the scouting expedition. Frank, however, pointed out the utter foolishness of overloading the Golden Eagle—more especially as they might have to bring back a heavy load. Being sensible boys, both Billy and Lathrop, therefore, soon got over their gloom.

Early the next morning, the final provisions were loaded into the aeroplane's chassis and her barometer, auto-clock and other instruments were adjusted by the Bolo's own and set in place. A careful note was then made of the Bolo's position and noted in Frank's pocket log-book. This done there only remained farewells to be said and these were necessarily brief.

It was ten-thirty o'clock on a cloudless, breathless morning that the Golden Eagle, with her pontoons empty, except for a supply of drinking water carried in the small reserve tanks at either end, shot into the air from the glassy sea.

Had any strangers been there to witness the start they could not have forborne to cheer at the sight the noble ship presented, soaring onward higher and higher, like a mighty sea-bird winging its way toward the unknown wastes of the mysterious Sargasso.



CHAPTER XIX.

THE RAT SHIP.

Strong of wing and sound of engine, the Golden Eagle sped on through the clear, warm air, the rushing sensation of her flight sending the wind in a cooling stream against the faces of the occupants of her chassis. From time to time, Ben scanned the vast flats of ocean below them with the glasses, but for some time nothing appeared in the field of the binoculars to warrant them in changing their course. Seen from above, the mucilaginous character imparted to the Sargasso Sea by the vast acreage of flowing seaweed, inextricably entangled, was clearly perceptible, even though from the deck of a ship the shallow layer of water that overlies the seaweed imparts the blue hue of open water to it and makes its treacherous character.

"It is like traveling over a water desert," declared Harry.

Far on the horizon were piled castellated cloud masses, seemingly immoveable and changing in tint as the day lengthened. On all the vast stretch beneath them was not a sign of life. It was an ocean solitude indeed.

Suddenly Ben who had the glasses in hand gave a shout.

"I make out something!" he exclaimed.

"Where?" cried Harry.

"About two points to the starboard—change your course a bit, Frank, and we'll be bearing directly up for it."

Frank gave the wheel a slight twist and the Golden Eagle obediently swerved off to the right.

"What was it you saw?" asked Frank.

"A ship, though whether it is the one we are after is doubtful," was Ben's reply. "I reckon there are enough ships drifting about in this tangle to stock up a dockyard."

It was not long before all doubt on this point was resolved. The object Ben had sighted was indeed a ship.

As the Golden Eagle soared nearer they perceived that the vessel was a small steamer—a craft of perhaps 2,000 tons, painted black with a yellow funnel. Except that no smoke curled upward from her stack and there was not a sign of life about her, she looked as if she might have just set out on a voyage. From her mainmast a flag hung, wrapped about the spar in the breathless atmosphere.

"I'm going to drop," announced Frank.

Instantly the Golden Eagle's steady, forward motion ceased and she began to descend with a rapidity that would have taken the breath away from less experienced aviators than her occupants.

It was like going down in a rapidly falling elevator.

She struck the water with a gentle gliding impact that hardly did more than ripple the surface, and a cheer broke from the boys as they perceived how perfectly the new pontoons worked.

"As easy as lighting on a feather-bed," was the way Harry put it.

The spot where they had settled was some little distance from the steamer, so, at a pace which would not raise the aeroplane from the water, Frank steered her toward the derelict.

Viewed even in the cheerful sunlight she was a melancholy object. Although at a distance it was not perceptible that she was an abandoned craft, a near view showed that it must have been some time, perhaps even a period of years, since she had been trapped in the Sargasso.

As she rose and fell in the gentle, heaving swell, the boys could see that long green weeds grew on her sides where the water laved them and her paint was blistered and flaked off in great patches, showing the rusty red of her iron plates beneath.

In the presence of this mystery of the ocean the boys grew silent as Frank maneuvered the Golden Eagle alongside and stopped the clattering motor.

The silence was profound.

Except for the occasional creak of a block as the derelict slowly swung to and fro it was as still as noonday in the desert. Even the usually light-hearted Harry was awe-stricken in the presence of the silent derelict.

Ben was the first to break the stillness.

"I'm going aboard," he announced, singling out with his eye a dangling rope which depended from a davit.

"Look, boys," he went on; "perhaps the poor fellows got away. See, the boats are gone."

"Let's hope they did," replied Frank, making fast the Golden Eagle to another of the dangling "falls," and preparing to follow Ben's example and clamber aboard.

Soon the boys stood on the main deck of the abandoned steamer, whose name they now saw was Durham Castle.

"She was a Britisher," declared Ben.

As he spoke there was a mighty noise like that of rushing water from the forecastle and the boys started back in affright. And well they might, for on the heels of the noise came a perfect torrent of rats. Gray rats, brown rats, young rats, old rats, thin rats, fat rats. They dashed directly at the boys, seeming mad with terror, or rendered ferocious from thirst or other causes.

Their little beady black eyes gleamed wickedly and their sharp yellow teeth were exposed.

The boys ran and Ben leaped into the main shrouds by which they had been standing, but the forerunners of this avalanche of crazed creatures was upon them. The rodents with squeaks and cries swarmed after the human beings as if they meant to devour them by sheer force of numbers.

"Shoot—shoot," shouted Ben, as he dashed from his waist a big brown rat that left the imprint of its teeth in his hand as he struck at it.

Frenziedly the boys emptied their magazine revolvers at the mass of swarming creatures and they fell dead in heaps at their feet. But still the onrush came and the lads shuddered with repulsion as they felt the tiny claws of the rodents fixed in their trousers as the creatures tried to swarm up them.

They seemed to have a leader. An immense gray fellow almost as big as a rabbit. A sudden idea came into Frank's head, he did not know at the time whether he had been told it, or read of it somewhere, but it seemed to him if he could kill that old gray leader the rest might take fright.

Hastily he fired, almost blowing the creature's head off, so close was it to him.

As the others saw their leader killed they hesitated, and Ben and Harry took advantage of the pause to empty a fresh magazine full of bullets into the closely packed mass.

It was the turning point.

With shrill squeaks and cries the rats turned and dashed for the other rail. As they reached it they swarmed over it madly, unheeding of the water beneath. In whole battalions they plunged into the sea, most of them sinking immediately; but some of them swimming about in circles with piteous cries. The sea was discolored with their swarming heads for some distance about the ship.

Suddenly there shot up from the seaweed a long fleshy arm covered with what seemed to be huge excrescences. It curved like a serpent and swept deftly within its grasp dozens of the struggling rodents. Other arms appeared waving and seizing on the rats as they swam desperately about.

The boys knew that the arms were the tendons of giant devil-fish that had scented from afar the feast of rats.

They shuddered as they thought of the fate of human beings who should be cast adrift in such waters. In a short time not a rat remained on the water and the arms too subsided and sank.

White and shaky from the creepiness of the scene they had just witnessed the boys turned to Ben. The old mariner was mopping the sweat off his brow with a huge, red bandanna handkerchief.

"Wall, boys, if that's one of the sights of the Sargasso," he said, "I'd prefer Africa or even the Everglades—oof."

"How could such myriads of rats exist aboard a ship?" asked Frank.

"Easy enough, boy. This ship was a sugar ship bound from New Orleans to England with raw sugar for refining I take it.—See the remains of the sugar bags scattered about where the rats dragged 'em?"

The boys nodded.

"Well, rats swarm aboard such ships if they are not kept down, and I suppose that when this craft drifted in here to the Sargasso, and her crew deserted her, that the rats just naturally multiplied till they ate the holds clean of sugar and gnawed into the water tanks. Then we come along and they figures on making a meal out of us. They're queer things are ship rats, look how they ran when their leader was killed," went on the old sailor. "No sailor would go to sea on a ship that hasn't got any aboard though."

"Why is that?" asked Frank.

"Well, it's the old saying, 'rats leave a sinking ship,' you know," rejoined Ben.

"Let's explore the ship," said Frank, "that is, if there are no more rats about. Thank goodness, there is no chance of our meeting any devil-fish aboard here."

"No, that's one good thing," put in Harry. "Ugh!—did you ever see such horrid looking things as those waving arms?"

Peeping down into the deserted engine-room, where the machinery was rusting and rotting from long neglect, the boys made their way aft to what had evidently been the quarters of the vessel's captain.

"Ah, here's his log-book!" exclaimed Ben, opening a volume which lay on a desk attached to a bulkhead, "but first let's look into the staterooms."

There were four of these, opening off from the main cabin and in each there were evident signs of a hasty departure. Clothes, books and nautical instruments lay scattered about in confusion. The boys did not come across anything though to show them the fate of the crew of the ill-fated vessel.

They therefore examined the log-book and found that, as Ben had surmised, the derelict had started on her last voyage from New Orleans to Liverpool laden with raw sugar. Her captain was Elias Goodall, and her first mate James Hooper. The day of her entrance into the fatal Sargasso was set down as June 21st, 1898. Previous to this date there had been several entries referring to a break-down in the engine-room, which caused the steamer to be driven miles off her course by heavy gales. It was undoubtedly in this way that she drifted into the fatal seaweed.

"Have got the engine going again," read the entry, "but the sky for days has been overcast and have had no chance to make observations. Know we must be miles off our course, however."

Below was the next record of the ship's fate.

"Chief Engineer Maxwell just informed me that something seems the matter with propeller.—Later—Found the propeller matted with huge growths of seaweed. Cleared it with some difficulty by shifting some cargo forward and then revolving wheel till, blade by blade, we cleared it with axes from the small boats."

June 22nd.—"Seaweed seems to be getting thicker. With difficulty we progress at all. Mate Hooper just suggested terrifying possibility.—Are we in the Sargasso?"

June 25.—"Since the last entry in the log, have learned that our fears were only too well grounded. We are indeed in the Sargasso and there seems to be no escape. Engine stopped working long ago. The propeller so matted with seaweed that we could make no progress. What will become of us?"

June 26.—"Have tried to keep true state of affairs from the crew, but they learned of facts in some way, and made a demand to take to the boats. I told them that our duty was to stick by the ship till all possibility of aid was exhausted. They seemed ugly; but for the present at least there is no sign of mutiny. If only we had wireless we might signal our plight."

June 28.—"The worst has happened. In attempting to drive the crew back from the boats, Chief Engineer Maxwell was instantly killed with a handspike, poor Hooper so badly wounded and beaten that he died half-an-hour ago and I myself wounded in the left arm. The crew have taken to the boats and two loads are now about half a mile from the vessel. The men are shouting. Something terrible must have happened—"

June 29.—"I have not been able to nerve myself until to-day to record the frightful interruption that occurred while I was penning the last lines. I was interrupted by a fearful shriek and hastening on deck saw a sight that will not be blotted from my memory till I go to my death. The boats seemed to be in the grasp of what appeared at first glance gigantic snakes. The men, unfortunate fellows, were trying to beat the creatures off and pull back to the ship. Their vain cries for aid were pitiful. I got the glasses, the better to see what was happening. My horror at what I saw then was so great that I can hardly set it down. The creatures I had seen were not snakes at all but the arms of huge octopi. They enwrapped the boats in every direction. Even as I gazed one boat-load was drawn beneath the surface. In a few minutes more all was over."

July 4.—"On this day, at home, all are celebrating and rejoicing, and here am I encircled with horrors, and adrift, as it seems, on a doomed ship. There is one boat left. I mean to lower it and try to reach the land or at least the open sea where I may fall in with a vessel. The rats are swarming everywhere. They have attacked the cargo in the forward hold and the noise of their fighting and struggling is terrible. Last night they killed my poor cat. I found her clean-picked bones on the fore-deck this morning. I can stay no longer on this horror ship.—God be with me."

Goodall,

Captain.

Here the pathetic record ended abruptly and of the fate of the unfortunate captain the boys had of course no inkling. They, however, took the log-book with them for delivery in the future to the vessel's owners, and ten minutes later were back on board the Golden Eagle.

"It feels good to be off that 'horror ship' as her captain called her," exclaimed Frank, as he started up the engine.

"I should say so," was Harry's reply, in a sobered tone, "and I suppose scores of other ships have met the same fate."

"Undoubtedly," said Ben, "every year vessels sail from the United States and foreign ports that are never heard of again. No accounts of storms are received during their voyages, yet they never reach port; undoubtedly many of them wind up in the graveyard of the Sargasso."

"I'm glad we have a good stout air-ship to carry us," exclaimed Frank, as the Golden Eagle soared into the air and soon left the derelict far behind.



CHAPTER XX.

THE GOLDEN GALLEON.

A sharp hail from Harry, who had the glasses, aroused Frank from a reverie into which he had fallen as the Golden Eagle skimmed along. It was some time since she had left the ill-fated Durham Castle.

"Look, Frank,—here, take the glasses," the younger boy cried excitedly,—"there's a queer-looking ship dead ahead of us—can she be the Buena Ventura?"

Frank surrendered the wheel to Harry and gave the object a prolonged scrutiny. Then he handed the glasses to Ben with a quiet:

"What do you make of her, Ben."

The old sailor held the glasses to his eyes for a space of ten seconds or more and then turned to the boys with an excited look on his face.

"Whatever she is, she is no modern ship," he cried, "she's got a high stern on her like a castle, and her masts and rigging are like no ship that sails the sea to-day."

"There's another ship over on the horizon," cried Harry, "looks like a wreck."

Ben took the glasses once more.

"It's the wreck of a barque," he announced. "Guess it's the one that Bluewater Bill was cast away on. If it is, that must be the galleon over yonder, 'cause Bill said she was close to his ship, and I guess vessels don't change their relative positions much in this place."

As the Golden Eagle rapidly approached the ancient vessel the boys went nearly wild with excitement.

The glasses were constantly trained on her and when Harry, who had kept the binoculars fixed on the vessel's stern, announced in a voice that quivered with suspense:

"I can see her name—it's Buena Ventura all right," they all broke into a shout.



The goal was reached at last then.

Frank sent the Golden Eagle swinging in a long graceful circle round the galleon, from whose tall masts still hung fragments of rotting sails, and finally settled alongside her towering wooden sides, which still bore tracings of the gilding and paint with which the old Spaniards loved to decorate their vessels. Her lofty stern was a mass of splendid carving and gilt work. In its centre, in faded paint was the figure of a woman, surrounded by stars and other heavenly bodies. The vessel's stern cabin windows also were richly embossed and gilded.

"If there's as much gold inside her as there is out we'll all be millionaires!" exclaimed Ben.

"How are we going to get aboard?" questioned Frank, as he gazed at the high, smooth sides.

"Yes, that's a problem. I don't see the rope Bluewater Bill used either. It must have rotted away," rejoined Ben.

"Let's circle round her," he went on, "maybe I can see a foothold and then I can get aboard and let down a rope to you boys."

Accordingly, the Golden Eagle was steered slowly round the great hull, and finally Ben selected a place to clamber up among the fretwork below the heel of the bowsprit. With a nimble leap he was soon clinging to the heavy carving, and rapidly swarming hand over hand to the galleon's deck. When he reached it, he flung down a rope with which the Golden Eagle was made fast to the galleon's side, and in a few minutes the boys stood by his side on the moldering deck.

As it was getting dark, there was not time to do a great deal that night. All they found opportunity to accomplish, in fact, was a brief exploration of the main cabin, which was magnificently hung in silks and velvets once splendid, now mildewed and rotting. The decorations of the place had been sumptuous evidently.

In the rear of the cabin was a pile of ancient-looking chests, heavily strapped with iron, and with great brass locks curiously carved affixed to them.

"The treasure chests!" cried Harry, trembling with excitement.

All three of the adventurers hurried across the cabin. In the afternoon-light that streamed through the stern-windows Frank fell on his knees and eagerly tried to wrench one of the locks off. Aged as it was, however, it resisted his exertions.

"Hold on!" cried Ben. "I'll get it off." He raised his heavily booted foot, as Frank drew back, and brought it down with a crash on the massive brasswork. With a rending and tearing of the worm-eaten wood the lock ripped loose and the lid, operated by some concealed spring, flew open.

The boys gave a shout of disappointment. Nothing in the way of treasure lay revealed—only a faded velvet cloak edged with tarnished lace.

"Wait a bit," cried Ben tearing off the cloak. "Ah!—"

A different sort of shout came from the boys' throats then. Beneath the cloak lay candle-sticks, gold and silver, great vases, gleaming dull yellow in the mellow light of the gloomy beamed cabin, bowls of the precious metal, splendidly carved, and small parchment bags bulging with the varied shapes of the coins they contained.

The boys dragged the contents of the chest and spread it in a glittering pile.

"So it was no dream of Bluewater Bill's after all," exclaimed Harry.

So excited were they that the boys were anxious to go ahead with the work of breaking open more treasure chests that night; but they yielded to Ben's entreaties and agreed to have supper and a good night's rest before they proceeded to their task. After a meal of bacon, coffee, bread and preserved fruit, cooked on the gasolene stove of the Golden Eagle, the boys professed themselves ready for bed.

"Better sleep aboard the galleon," said Ben.

"Why?" asked Frank.

"Why, we don't want any of those devil-fish coming snooping around in the night, do we?" asked the old sailor, "and they might, if we slept so near the water."

"I should say not," exclaimed Harry, with a shudder at the bare idea.

"Say Frank," exclaimed the younger lad, an hour later, when they were snuggled under blankets—for there is a heavy dew and night chill on the Sargasso—on the deck of the Buena Ventura, "what would you do if the door of the cabin yonder should suddenly open and an old don all in armor should come stalking out and say:

"'Get hence, get hence, young marauders, and leave my treasure untroubled!'"

"I'd offer him a ride in the Golden Eagle to clear the cobwebs out of his brain," said Frank sleepily.

The treasure hunters were astir early the next day and immediately after breakfast—a hearty meal cooked on the Golden Eagle's stove,—had been despatched they were ready for work.

It had been determined to go at the task systematically, so Frank in a notebook, checked off the articles as chest after chest of valuable gold and plate was dragged from the galleon's cabin. He soon had his book full and was compelled to borrow a small pocket diary from his brother.

"I say, Frank!" exclaimed Harry, as he and Ben drew from the moldering chests piece after piece of dull golden ornaments, some of them studded with jewels that blazed as they caught the sun. "What should you say this stuff was worth, as far as we have gone?"

"Every bit of $50,000 I should imagine," replied the elder boy, "although I'm not much of a judge in such matters."

"Hurray, Ben! that will make us all rich," shouted Harry.

"Say," remarked Ben, pausing in his task of emptying a squat chest, marked, Don Ramon De Guzman, Sevilla, "you don't think I'm going to touch any of this loot do you? It all belongs to you boys and Bluewater Bill, and I've no right to a cent's worth of it. The excitement is enough for old Ben Stubbs."

"Well, you've got a nerve!" cried Frank, "to think that you are not going to get a share. Why we are all in on this, and, when we have all the stuff out and get it valued, we'll divide it up in fair proportion."

"You won't get me to take any of it," grumbled old Ben obstinately, grubbing away in the treasure-filled box.

"We shall see about that," said Frank, who knew it was useless to argue with the old sailor.

As they worked feverishly, from time to time gazing at the sky in apprehension of the appearance of Luther Barr's dirigible, the adventurers had an illustration of the manner in which the old Spaniards guarded their treasure that came very near having a tragical termination.

Ben Stubbs had hammered off the lock of a huge chest, with a semi-circular top, and was in the act of flinging back the lid, when he stopped short with an exclamation. It was fortunate for him that he paused, for as he did so, the lid, actuated by some hidden mechanism, swung back and a steel arm, tipped with sharp prongs, shot out. Had the sailor been less nimble the device would undoubtedly have caved his skull in. As it was, it missed him only by an inch.

"Well, that's a nice murderous contrivance," gasped the astonished sailor.

An examination showed the boys that the tips of the prongs were stained and they had little doubt, as they examined it, that the marks were those of human blood. The life fluid of some old-time marauder who had paid with his life for his attempt to rifle the chest. The death-bearing arm, they discovered, was actuated by levers and springs, connecting with the lifting mechanism of the lid. The boys were compelled to admit, as they examined the device, that fiendish as it was it had been designed by a master mechanic of his time.

As they worked, you may imagine, the boys swept the sky for a sign of Luther Barr's dirigible, but not a trace of her did they discover that day.

"It begins to look as if we had beaten Luther Barr this time," cried Harry, exultingly.

"Don't be too sure," was Frank's cautious reply. "He is capable of going to any lengths to satisfy his lust for gold, and I am sure he would stop at nothing to get the treasure from us. We may have a lot of trouble on our hands yet."

The treasure as it was catalogued was placed in canvas sacks brought for the purpose, and by supper time that night all the chests had been pretty well emptied and the sacks lay distributed in such a manner as not to interfere with her equilibrium on the Golden Eagle's deck.

"It's going to make a heavy load," said Frank, shaking his head as he looked at the pile.

"We've got to take it all out at once, however," said Ben, "or we would be pretty sure not to find any when we came back."

"It's very certain that Barr cannot be far off," said Harry, gazing about at the opal sunset sky.

"Well, if he comes to-morrow he'll come too late," said Frank, "for we'll be far away from here by then. I intend to sail at dawn."

"That's the idea," was Ben's comment, "no use wasting time on a job of this sort. It's a good thing the weather has kept so clear, otherwise we might have had trouble; aside from old Barr's brand."

"I must confess it was a surprise to me to find that he had not reached here ahead of us," went on Frank; "you know we lost a lot of time in that storm."

"Maybe something went wrong with the dirigible before they started," suggested Harry.

"I guess that must be it," said Ben; "otherwise you can bet he'd have gotten on more of a hustle than this."

"Well, I'm just as well content with things as they are," commented Harry, "in fact it would not grieve me much to hear that his old balloon had tumbled into the ocean, crew and all."

Supper was soon despatched that evening, and the boys turned in early. They slept soundly, but toward midnight Frank had a queer dream. It seemed to him that he was on board the rat ship once more and that scores of the rodents they had battled with were again overwhelming him. He battled bravely with the hosts but they were too many for him. Just as it seemed that all was over, however, he heard a voice say, "Hold on there!"

So startlingly clear was the voice that Frank awoke as it uttered the words and almost gave a cry, which he instantly checked, as he perceived that it was no dream-voice he had heard.

As he listened intently he heard the voice once more.

"Hold on there—this is it."

The words seemed to come from overhead.

Gazing upward, the boy saw, hovering between the deck of the galleon and the stars, a large black object.

He instantly knew it for what it was.

Luther Barr's air-ship!



CHAPTER XXI.

DIRIGIBLE VS. AEROPLANE.

A galvanic shock passed through the boy at the discovery, and he silently crawled to where Harry and Ben lay and placing his hand over their mouths he in turn awoke them.

"Don't utter a word," he whispered, "Luther Barr's air-ship is here."

From the spot in which they crouched, keeping as closely in the shadow of the stout mast as they were able, the adventurers could hear distinctly the conversation of the men in the dirigible.

"This must be the galleon," Frank heard a voice he recognized as Sanborn's saying, "it's lucky we decided to keep on."

"Well, we might as well have turned back for all the good we can do now," came another voice—that of Malvoise. "I'm not going to run a chance of wrecking the ship by making a landing in the dark."

"What, you are not going to descend?" came Sanborn's voice in a querulous tone.

"Not much," was the rejoinder. "What's the use of risking our necks and taking a chance on smashing up the air-ship. If she is damaged we would be stranded here and leave our bones in the Sargasso in all probability."

"That's so," chimed in another voice—that of the inventor Constantio. "It would be very dangerous, senor, to make a landing to-night. Let us go back to the island and start out to-morrow again."

The boys exchanged glances. So the Barr party had encamped on an island; doubtless one of the numerous little keys that abound in those waters and which, had they water on them—which few have—are ideal spots.

"That's my idea, Sanborn," went on Malvoise, "come, shall I put her about and sail back?"

"Let's circle the ship first," exclaimed Sanborn. "So far as we know we are here ahead of those Boy Aviator cubs, but we can't tell positively unless we make an examination."

Frank's heart stood still. If they circled the ship there was little doubt they would spy the Golden Eagle floating alongside; in black shadow though she was. His fingers closed on his revolver. But fortunately there was no need to use weapons then, for Sanborn's idea was overruled, and from the position in which the air-ship hovered she could not spy the aeroplane.

"No; come on, let's get back," urged Malvoise; "there is something wrong with one of the cylinders and I want to fix it before we tackle the job of taking off the treasure."

"Very well then," said Sanborn, yielding to the will of the majority. "We'll get back, but I want to be here first thing in the morning and make a thorough overhauling of the ship. There ought to be enough gold aboard her, from what I overheard Bluewater Bill say, to make us all kings."

"Ah, then I can invent more dirigibles, large ones to carry passengers across the Atlantic," the boys heard Constantio say—though of course, till Ben told them, they were not aware of the speaker's identity.

To their great relief the engine of the dirigible, which had hovered stationary above the galleon during the men's talk, was once more set in motion and the big air-ship drove off at a rapid pace.

"Phew! that was a narrow escape," exclaimed Frank. "I don't want many more like that, I can tell you."

"If they had only gone round the galleon they could not have escaped spying the Golden Eagle," said Harry.

"Fortunate for them they didn't," said Ben grimly, fondling his blue magazine revolver; "they'd have got some indigestible leaden pills, I'm thinking."

"Shooting is just what we want to avoid," said Frank. "I never want to have to fire on a human being."

"Well, if they fire at you first, what are you going to do?" was Ben's incontrovertible argument.

Naturally the Boy Aviators and their companion slept no more that night. The remaining hours before daybreak were occupied with getting everything in first-class shape aboard the Golden Eagle in readiness for what might prove a dash for life.

"Are we faster than the dirigible?" asked Harry, who realized as well as his brother that there might be a chase between the two air-ships.

"I don't know," was Frank's reply, "we ought to be; but from Ben's description, and what we saw of her, that dirigible must be at least a hundred and fifty feet long and she has a more powerful engine than we have."

"But look at her weight," argued Harry.

"That doesn't cut so much figure if you have a powerful enough engine to overcome it," was the reply; "some European dirigibles, bigger than Luther Barr's, have made eighty and even ninety miles."

"Well, we wouldn't stand much chance with an affair like that and that's a fact," commented Harry.

"We can only hope things won't come to such a pass," said Frank.

Soon all was ready for a start and Frank, taking careful bearings, headed the Golden Eagle round on the course she had followed on her way to the galleon. As the sun poked his rim above the horizon the Golden Eagle shot into the air and rapidly the hulls of the galleon and Bluewater Bill's castaway hulk were mere specks behind them.

The spirits of the boys rose. They breakfasted on cold stuff cooked before they started and coffee heated over the exhaust of the engine. Ben lit his pipe, and with Frank at the wheel and Harry on lookout, any one looking at the party in the Golden Eagle would have said that they were a trio of pleasure-makers instead of adventurers engaged on a daring dash for fortune.

It was about nine o'clock in the morning when the danger they had feared loomed up out of the clear sky as suddenly as a tropic squall.

Coming straight toward them, but a mere dot on the sky, though momentarily growing larger, was an air-ship that they could not doubt was Luther Barr's.

"What are you going to do?" asked Harry, as Frank put the wheel over and brought the aeroplane on a course which would take her far to the westward of the dirigible.

"Try to avoid her," was Frank's reply; "they are equipped with a rapid-firing gun and could make mince-meat of us in a short time."

"We have rifles," said Harry.

"They would be little use against such a weapon," replied Frank.

But as the Golden Eagle shifted her course it became clear to those aboard her that the other air-ship did the same.

"They have seen us," gasped Harry.

"Yes, and mean to pursue us, too," was Frank's reply, through gritted teeth; "well, we'll give them a long chase of it."

The Golden Eagle was speeded up to her full capacity, although with the heavy load she was carrying, she by no means attained the speed of which she was capable.

In one thing, however, she had the advantage over the dirigible. She could maneuver with twice the speed and turn and twist like a snake, while the more cumbersome air-ship took a lot of handling to navigate in any intricate movements.

As the dirigible drew nearer, the boys, critical as was the moment, could hardly restrain their admiration at the fine appearance she presented. Her distended gas-bag shone in the sunlight like silk and her cabin woodwork sparkled where brass handholds and plates were attached to it, like the main deck of a passenger liner.

Suddenly, however, her sinister character became apparent.

There was a puff of smoke from what, if she had been a "sea" ship, would have been her bow, and a projectile sang by the Golden Eagle. "That was a warning shot, Frank," cried Ben; "the next will come closer."

"I am going to watch them get ready to fire and then drop suddenly," said Frank, his face white, but with a set, determined look on it.

The man at the lanyard of the dirigible's gun, who looked like Sanborn, bent low over the weapon once more and adjusted it carefully for a second shot, the helmsman of the air-ship at the same time swinging her so that she would be on a direct line with the Golden Eagle.

Frank watched his every movement with a hawk-like intensity. Just as Sanborn stepped back, lanyard in hand, to fire a second shot, Frank dived like a sea-gull sweeping down on a fish and the missile whistled harmlessly overhead.

At the same instant Ben Stubbs, unable to restrain himself any longer, snatched a rifle from one of the lockers and aimed at the pilot-house of Luther Barr's craft.

A shower of splinters flew from the casing of a porthole as his bullet struck, but no further harm was done.

The aeroplane was now far below the dirigible, which was soaring at a height of two thousand feet. At such an angle it was impossible for those on board to use their rapid-fire gun, and Frank, setting the Golden Eagle's rising planes, soared rapidly along at an elevation of about two hundred feet.

By the time the men on the dirigible had got her round, the Golden Eagle was two miles ahead of the gas-suspended craft.

"We've escaped them," cried Harry.

"Not yet," said Frank; "don't holler till you are out of the woods. They know now we've got the treasure and they are not going to give up the chase as easily as all this."

From time to time the dirigible, which was not gaining on the Golden Eagle, fired a shot from her forward gun, but the dipping, scudding aeroplane afforded a poor mark and, moreover, the deck of a dirigible at full speed is not the steadiest place in the world. So after a few attempts more to wing the swift aeroplane, the crew of the dirigible gave the effort up and turned all their attention to getting every ounce of speed out of their craft. With sinking hearts the boys realized that she was gaining on them.

Hour after hour, above the glassy Sargasso Sea, the battle went on, the aeroplane ducking and diving and gliding and skimming whenever the dirigible got a good chance to send a fatal projectile into her.

From time to time, also, Ben got a chance to send a bullet crashing into the dirigible's gas-bag, and from the actions of the men aboard her they were evidently badly worried by this. However, as Ben knew, the gas-bag of the dirigible was constructed in sections and the gas manufactured by Constantio was so buoyant that if even one section remained intact it would still serve to sustain the dirigible in the air.

But no fight of such a character can endure long. Sooner or later one or the other of the combatants is bound to succumb, and so it was in this case.

Just as Frank was making a dive to avoid, for the twentieth time, getting within range of the dirigible's gun, a skillfully aimed projectile came crashing through the Golden Eagle's gasolene tank. The fluid poured out in a flood.

A few minutes later the engines ceased to revolve and the aeroplane was compelled to descend, Frank driving her down in a long arc that brought her to the surface of the water without accident.

Crippled as she was, the Golden Eagle could not be set going again without repairs that would take hours.

In the meantime their opponents had taken advantage of the aeroplane's plight to riddle her wings with bullets.

Brave as the boys were, they were not foolhardy.

Ten minutes after the fatal accident to the tank, Ben Stubbs, with bitter protests, waved a white shirt in token that the occupants of the Golden Eagle were driven to surrender.



CHAPTER XXII.

ON BOARD BARR'S SHIP.

"Do you surrender?" shouted a voice through a megaphone from the dirigible as it hovered above the stricken aeroplane.

"Yes, hornswoggle you," roared Ben Stubbs, "but if it hadn't been for that gas-bag of yours you'd never have got us, and I can lick any man aboard yer with my fists or any other weapon."

Luther Barr's men paid no attention to this outburst and the boys were too sick at heart at the complete failure of their venture even to hear Ben's words. Frank choked back his tears with difficulty and Harry gazed straight out over the sea.

It was defeat final and complete.

"Make fast the ladder and we'll board you," was the next hail as a trap in the under side of the dirigible was opened and a long rope ladder came snaking down.

Ben, although he would cheerfully have slashed it to bits with his sea knife, had no recourse but to make the end of the apparatus fast to the Golden Eagle's framework, and a few seconds later Malvoise came rapidly down it. To guard against any attack on him the men on the dirigible leaned over the rail and kept their rifles covering the boys and Ben.

"Hum, you saved us the trouble of packing up the treasure, I see," said Malvoise, his eyes sparkling as they fell on the sacks of treasure.

"If we'd only fixed you last night when you was in the air over the galleon we'd have done a good job," growled old Ben.

"Ah, you think so," grinned the Frenchman. "I don't doubt that it feels bad to be the conquered, but you must not grudge us the treasure, my dear Mr. Stubbs—"

The sneer on his face was unbearable and Ben started forward to fall upon him, but as he did so a bullet from above zipped down, narrowly missing his arm. In fact, it ploughed through his loose shirt-sleeve.

"You see, I am well protected," grinned the Frenchman, as Ben started back.

"Yes, I reckon we've got to give in with as good a grace as we can," grumbled Ben; "though I'd give all the treasure in them sacks to get my hands on you for just five minutes," he muttered to himself.

"Let down a tackle there, you," shouted Malvoise to the crew of the dirigible, "and you, Sanborn, come down aboard here. We must get the treasure on board before it starts to blow at all."

Sanborn came hastily scrambling down the ladder, and a few seconds later a block and tackle were lowered. Malvoise and Sanborn, who greeted the boys with a scowling sneer, first deprived the boys of their weapons and forced Ben to give up his revolver and then made fast the block and tackle to the first of the treasure sacks.

It was rapidly hauled up to the dirigible; the other treasure bags followed in the same manner. In half an hour the Golden Eagle was swept clean of the contents of the galleon's chests which the boys had loaded on her with such light hearts.

"Now, then, I guess we are all ready for a start," said Malvoise, when the last of the sacks had been hauled into the dirigible's cabin. "As a matter of fact," he went on, "I suppose I ought to leave you here, as you only will make a lot more weight in the air-ship, but I am more humane than that and I'll allow you to come on board. Up the ladder with you, and briskly now."

Ben went first, followed by the two boys; behind them came Malvoise.

"Come on, Sanborn," shouted the Frenchman to his companion, who still lingered on board the aeroplane.

"Wait a minute. I've got a job to do first. I want to sink the thing for all time," cried the other.

The boys, who had by this time gained the swaying deck of the dirigible, saw the treacherous mechanic deliberately draw a pistol and prepare to fire a hole in the pontoons, which would inevitably have sunk the gallant craft.

But as his finger pressed the trigger the man's foot slipped and he was dumped off the pontoon into the water.

His companions, far from being alarmed, shouted with laughter at his mishap, as Sanborn, cursing, prepared to climb back on to the Golden Eagle. But even as the oaths left his lips a change came over his face. It turned an ashen gray.

"Help!" he shouted.

"What's the matter?" roared Malvoise.

"Something is after me!" came the agonized cry of the man.

As the words left his lips a cry of horror broke from all on the dirigible's deck who were watching Sanborn's struggles.

A great arm, covered with mouths, like the ones the boys had seen absorb the rats, shot out of the sea. Another and another followed it, and hapless Sanborn, screaming in terror, was dragged from the structure of the aeroplane, to which he clung with a drowning man's clutch.

"It's a devil-fish," shouted the boys.

"Fire on the thing," shouted Malvoise, pouring the contents of his revolver down into the fleshy mass of the octopus.

Instantly a great cloud of inky fluid spread over the waters and into the opaque waves the waving arms sank, dragging with them to the depths of the sea the treacherous mechanic.

Shocked and sickened by the scene, the boys turned away and even Malvoise seemed powerfully affected. He hid his face in his hands as the wounded monster slowly sank without relinquishing its hold on its victim.

As for Constantio and a red-headed bushy-whiskered man, whom the boys learned later on was Sam Wells, one of the three men who helped in working the dirigible, they seemed completely unnerved by the sight they had witnessed. Malvoise's sharp voice recalled them to themselves.

"Come now, collect your wits," he shouted; "poor Sanborn's gone, and we can't save him. Cut loose from the aeroplane and haul up the rope-ladder. Constantio, you take the wheel. Wells, when you have got the ladder aboard, turn to and stow that stuff further aft."

He indicated the pile of treasure sacks.

Wells and two other men who had been standing about the deck instantly busied themselves obeying these orders. It was evident from their implicit obedience that Malvoise was master on the dirigible.

As the engine was set going and the ship forged ahead, leaving behind it the wrecked aeroplane and the watery grave of Sanborn, Malvoise called the boys' attention, in a half-joking way, to the damage Ben Stubbs' bullets had done to the gas-bag.

"However," he went on, "fortunately it does not make so much difference as it would in any other air-craft. After dinner I will send one of the crew aloft to put a patch on the hole and we can then re-inflate that section from one of the hydrogen tubes."

Precarious as their situation was, the boys, whose interest in aeronautics was a sort of ruling passion with them, could not but help being interested with the perfect working out of all details aboard Luther Barr's craft. After an excellent dinner, in which fresh meat and vegetables from a well-stocked ice-box formed the staples, they watched with interest the red-headed sailor, Wells, scramble up into the network of the bag and sew a patch over the bullet hole made by Ben Stubbs' shot. The patch affixed, it was coated with a water and gas-proof solution the sailor carried in a small pot suspended round his waist. After an interval allowed for drying, a cylinder of gas was dragged out of the after storeroom where they were kept, and the section which had been injured was refilled by means of its own inflation hose, which was provided with a nozzle adjustable to the mouth of the gas receptacle.

To the boys' surprise, when darkness fell the dirigible still forged ahead and no change of her course was observable. They had imagined that she was on her way to join Luther Barr at some nearby meeting-place, where the Brigand would take the treasure on board, but, so far, her navigators showed no intention of alighting.

At ten o'clock Malvoise stepped up to the three adventurers and said:

"It is a rule on board that all lights shall be extinguished at this hour. If you are ready for bed I will show you to your sleeping place."

He led the way to a small cabin fitted with two bunks and lounge. The boys wanted to ask a score of questions, but knew it would be useless, so remained silent.

"I wish you a good night's rest," said Malvoise as he switched on a tiny electric light with the warning that the dynamo would be cut off in ten minutes' time.

As he closed the cabin door behind him there was a sharp click.

The cabin door was fitted with a stout spring lock.

The adventurers were prisoners a thousand feet in the air.



CHAPTER XXIII.

PRISONERS IN DIRE PERIL.

"Locked in, by gosh!" exclaimed Ben Stubbs, as the lock clicked.

"What can they mean to do with us?" wondered Frank.

"So far we've been treated like lords, but I don't like the idea of being penned up in this cabin," said Harry.

Much more speculation was indulged in by the boys, but without their arriving any further at an accurate idea of what was likely to be their ultimate fate at the hands of Luther Barr's men. While they were still talking the light went out, as Malvoise had warned them it would, and they were plunged in total darkness.

Not being heroes of romance, but just healthy boys, the two lads were asleep a few minutes after they threw themselves in their bunks, which were provided with excellent springs, and bed-clothing of good material. As for Ben Stubbs, as he himself said, he could have slept on a whale's back so long as the animal didn't dive.

How long he slept Frank had, of course, no means of estimating, as it was too pitchy black in the cabin for him to see the dial of his watch, but he opened his eyes with a start and soon found out that he had been aroused by what seemed an unusual disturbance aboard the dirigible.

He heard the trampling of feet as the crew ran to and fro, and the shouting of orders in Malvoise's voice. The cabin port was closed and locked on the outside, although the cabin seemed perfectly ventilated by some other aperture; so it was impossible for Frank to distinguish what was said, but the tones of the Frenchman's voice conveyed intense excitement.