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THE AEROPLANE BOYS ON THE WING

or,

Aeroplane Chums in the Tropics



BY
JOHN LUTHER LANGWORTHY


1912



The further trials and triumphs of the venturesome aeroplane lads are
set forth in a particularly thrilling manner in the third volume of this
series, now on sale everywhere, and which is entitled, "The Bird Boys
Among the Clouds; or, Young Aviators in a Wreck."



CONTENTS

CHAPTER


    I. ON THE WAY BACK FROM THE GAME

   II. FRANK'S WAY

  III. SOMETHING ABOUT THE BIRD BOYS

   IV. A STARTLING DISCOVERY

    V. A WARM FIVE MINUTES

   VI. IN SEARCH OF A CLUE

  VII. ANDY RECEIVES A SHOCK

 VIII. THE MESSAGE

   IX. UNDER TROUBLED SKIES

    X. NIPPED IN THE BUD

   XI. OUT OF THE FRYING PAN INTO THE FIRE

  XII. A GREAT SURPRISE

 XIII. THE "DEVIL-BIRD"

  XIV. THE AIRSHIP LAUNCHED AT LAST

   XV. AN UNPLEASANT SURPRISE

  XVI. THE AIR CHASE

 XVII. THE CAMP IN THE TROPICAL JUNGLE

XVIII. WHEN FRANK STOOD GUARD

  XIX. FIREBRANDS AND JAGUARS

   XX. THE AEROPLANE BOYS ONCE MORE AFLOAT

  XXI. THE LAST LITTLE HOT AIR BALLOON

 XXII. RESCUED

XXIII. HOMEWARD BOUND--CONCLUSION




THE AEROPLANE BOYS ON THE WING

or, Aeroplane Chums in The Tropics

       *       *       *       *       *




CHAPTER I.


ON THE WAY BACK FROM THE GAME.

"But the Bird boys won the prize of a silver cup!"

"What if they did? It was by a hair's breadth, Mr. Smarty!"

"And their monoplane was proven to be faster than the big biplane you
built, Puss Carberry!"

"Oh! was it? Don't you be too sure of that, Larry!"

"Didn't it land on the summit of Old Thunder Top ahead of you and Sandy,
in the race that afternoon? Tell me that!" and Larry Geohegan bristled
up to the recognized bully of Bloomsbury, while a dozen fellows
clustered around on the deck of the big power boat, listening eagerly to
this war of words.

They were on their way home from a very exciting game of baseball that
had been played at Cranford, across the lake. And after ten innings of
hot work the nine from Bloomsbury had won. But not until they had
changed pitchers, upon tying the score in the ninth, after coming up
from behind.

Puss and Larry both wore the uniform of the home players, and there were
others on the boat who also belonged to the team. In fact, the staunch
vessel had been placed at the disposal of the baseball club for this
day, by Commodore Elliott, the rich owner.

Larry had never been one of the adherents whom Puss could call upon to
back him up when he tried conclusions with a hostile faction; in fact,
Larry had always been an admirer of Frank Bird, who was recognized as
the most persistent rival the bully had ever encountered in his whole
career since coming to Bloomsbury.

Puss allowed a contemptuous expression to take possession of his face,
and even shrugged his broad shoulders, after a nasty fashion he had,
that often angered the one he was arguing with more than words could
have done.

"Aw! rats!" he said, in a disagreeable, rasping voice. "Everybody knows
that I'd won that same race only for trouble with my engine. Frank was
lucky, just like he generally is when he goes in for anything. Look at
him today, being called in to pitch in the tenth! We had 'em badly
rattled, and they were on the toboggan sure. Yet Frank, the great hero,
gets credit for winning that game. Didn't the Bloomsbury crowd cheer
him to the echo, though, and want to ride him on their shoulders? Wow!
it makes me sick, to see such toadyism!"

"What's all this big noise about, fellows? Didn't I hear my name
mentioned?" asked a tall lad with a frank face and clear brown eyes, as
he pushed forward.

It was Frank Bird himself, who had been talking with his cousin Andy,
and several other fellows, in the bow of the launch, and by accident
heard the voices that were raised in dispute.

Percy Carberry, known among his comrades simply as "Puss," did not
flinch when he found himself face to face with the boy he detested so
thoroughly. They had never as yet actually come to blows; but Puss
believed that his muscular powers were far superior to those of his more
slender rival, and just now he was in a particularly bitter frame of
mind.

"Oh! so you're there, are you?" he sneered "I was just telling your good
friend Larry here that I considered you a greatly overrated substitute
pitcher; and that luck had as much to do with our winning that game
today as anything you did."

Frank Bird laughed in his face.

"Sure," he declared, cheerily. "I was a mighty small factor in the
victory, for I only played in one short inning. If I'd faced those hard
hitters of Cranford nine times I reckon it'd be hard to tell what they'd
have done to my poor inshoots and curves."

"But you held them in that inning, Frank, you know you did!" cried
Larry.

"Mere accident, my boy. Happened to be the weak end of their batting
list!" observed Frank, as if determined to agree with his enemy, and
thus spike his guns.

"Is that so?" demanded "Elephant" Small, who did not happen to be on the
nine, because of his customary slow ways. "Perhaps you'll be saying that
dandy two-bagger you whanged out, that brought in the winning run, was
also an accident?"

"Well, I must have just shut my eyes, and struck. I seem to remember
hearing a sound like a shot, and then they all yelled to me to run; so I
did, going on to second in time to see Peterkin gallop home," and Frank
looked as sober as a judge as he said this. The others saw the joke,
however, and, led by Larry, burst out into a laugh that made Puss and
his loyal backers scowl.

"If that bingle was an accident, don't we wish we had a few more players
who could shut their eyes and meet Frazer's terrible speed balls and
curves in the same way!" one fellow exclaimed.

"So say we all of us!" another cried.

Puss realized that the majority on board the _Siren_ were against
him. But he was not given to taking water; even his enemies, and he had
many in Bloomsbury, could hardly say that Puss was lacking in a certain
kind of grit; while stubbornness he possessed in abundance.

So he just shut his white teeth hard together, and looked scowlingly
around the bunch of fellows. And many of them felt a little chill when
those cold gray eyes rested upon them; for they knew of old what
happened when Puss Carberry made up his mind to mark a boy for future
attention.

Frank still stood there by the side of the boat, smiling. Perhaps his
very apparent unconcern served to make the other still more angry. There
had been bad blood between these two lads for a long time, and more than
once it threatened an eruption, which somehow or other had up to now
been stayed.

Although some weeks had passed since the much-talked-of race between the
rival aeroplanes, piloted by these two boys, in which Frank took his
little craft up to the lofty summit of Old Thunder Top ahead of Puss in
his biplane, as narrated in the first volume of this series, entitled
"The Bird Boys; or, The Young Sky Pilot's First Air Voyage," the latter
had never ceased to feel ugly over his defeat.

As usual he had what he considered a good excuse for his arriving
second; but few persons ever knew how Puss and his helper Sandy had
tried to injure Frank's airship when it was directly beneath them, by
deliberately dropping a sand bag, taken along, singularly enough, as
"ballast," but with this very idea in view.

"Seems to me you've gotten the big head ever since you happened to drop
on that rocky plateau on top of the mountain just three little seconds
ahead of me, Frank Bird!" he said, with a steely glitter in his eyes
that those who knew him best understood to mean coming trouble.

"Oh! I hope not, Puss," replied the other, with a smile. "I give you my
word my hat fits me just as comfortably as ever. It was a close race,
and the one who got there first hadn't much to crow about, for a
fact. We happened to be lucky not to have any trouble with our new
little Kinkaid engine, that was all."

"Huh!" grunted his cousin Andy, shaking his head, and scowling at Puss
in turn. "But we had plenty of other sorts of trouble, all the same,
sand bags full of it, in fact. They just rained down on us; but then
Frank knows how to check up his engine suddenly, and the storm passed by
without any hurt!"

Some of the fellows, who happened to know what this sly reference on the
part of the hotheaded Andy meant, began to chuckle. Of course such a
thing would only serve to make Puss more angry. He chose to believe that
they were all only trying to bait him.

Frank in particular came in for his dark looks. And Larry, who had once
run in the same company as Puss, so that he knew his whims better than
many others, took occasion to give Frank Bird a sly nudge in the side,
as he whispered:

"Look out for him, Frank; he's getting near the danger point, sure!"

But Frank did not have to be warned. He had grown tired of warding off
this ever threatening danger of a broil with Puss Carberry. Like his
cousin Andy, the other had no father; and his wealthy mother had long
since given up in despair the idea of controlling the headstrong lad. So
that Puss had his way, whenever he wanted to do anything out of the
ordinary.

Because Mrs. Carberry was one of his father's patients, and Dr. Bird
esteemed her very highly, Frank had postponed the reckoning just as long
as he could endure the insults of the bully. But he believed the last
ditch had been reached, and was determined to no longer raise a hand to
avert the threatening storm.

Puss had turned when Andy spoke, to flash a look in his direction. But
it had no effect upon the other, who could be as reckless at times as
the next one. Indeed, Frank often had to curb the impatience and daring
of his chum.

"Oh! that's what sticks in your craw, does it, Andy Bird?" demanded
Puss. "Just because Sandy happened to drop that ballast, thinking we
might make better time if we lightened ship, you choose to make all
sorts of nasty insinuations about us wanting to knock you out! Shows
where your mind is. Another fellow wouldn't ever let such a fool notion
get a grip on him. And you'd better put a reef in that tongue of yours,
my boy, unless you want to have it get you into trouble."

Andy flared up at once, and would have replied; but Frank calmly stepped
in between the two, as though he claimed first right.

"Neither of us have charged you with intentionally trying to disable our
aeroplane by dropping that sand bag, Puss," he remarked quietly. "All we
say is that it was a queer coincidence you wanted to get rid of your
ballast just when we were walking up on you hand over fist, and about to
pass under you, to take the lead. That's all!"

Again there was a low laugh from among the boys who stood around
listening. To them it was a rich treat to see the recognized bully of
Bloomsbury baited to his very face in this characteristic way; and they
were enjoying it hugely.

"Well, let me tell you it ain't all, not by a jugful!" exclaimed Puss,
his face taking on a purple hue, as it always did when he became
enraged. "Both of you fellows have got to stop speaking about that sand
bag dropping, or there's going to be a licking in store for you. See?"
and he thrust his face close to that of Frank as he said this. Larry
Geohegan fairly held his breath. "Now it's coming; don't I know the
signs?" he whispered to the boy next him.

Frank continued to stand there, close to the side of the speeding
launch. They were about half way across the deep lake at the time.
Evening was coming on, for the sun had just reached the distant rugged
horizon in the west.

"Do you refer to me when you say that, Puss?" he asked, with that same
queer little smile on his face--a look that mystified the other, who
could not understand what it meant.

"Yes, both you and that loud-mouthed cousin of yours. Just because luck
favored you, and you won that blooming race by a head, you think I can't
manage an aeroplane as well as you. Huh! perhaps you don't know that I'm
going to take my machine with me when I go down to the cocoa plantation
we own along the Amazon, and use it exploring where a white man has
seldom been seen. You can just stay here and grow up with the country,
while I'm doing great stunts. But as long as I stay here I'm going to
stop this talk about trickery and low-down dodges. You're responsible
for most of it, Frank Bird. I warn you what's coming to you."
"Perhaps," said Frank, pleasantly, "you would be kind enough to tell me
also when this awful punishment is going to fall on my poor devoted
neck?"

"Any time, hang you! Right now, if you say another word!" roared Puss,
doubling up his fists, and making ready for one of his well known and
feared bull rushes, that had brought him a speedy victory many a time.

"So? That's comforting; and with all these good fellows around to see
how you wipe up the deck with me. Suppose you begin the swabbing act,
Puss!" and Frank pretended to throw himself in a position of defense.

The other gave utterance to a hoarse cry of rage, and lowering his head
after the manner of a bull, jumped forward. But the agile Frank simply
stepped aside; and unable to check himself in time, Puss Carberry shot
over the side of the power boat, disappearing in the clear waters of
Sunrise Lake with a great splash.

"Oh!" shouted his crony, Sandy Hollingshead, standing there as if
petrified; "and Puss can't swim a single stroke, either!"




CHAPTER II.


FRANK'S WAY.

"My goodness, what a splash!"

"Served him right, that's what!"

"He's gone under, fellows! Dove just like a big frog!"

"Stop the boat! He'll drown!"

Half a dozen were shouting in unison, as the boys crowded to the side
over which the bully had pitched when Frank avoided his forward rush.

But Frank heard only that startled exclamation from Sandy Hollingshead:

"Puss can't swim a single stroke, either!"

With Frank Bird to think was to act. The two things were almost
synonymous in his mind. Forgotten was the fact that the imperiled lad
had been endeavoring to strike him in the face at the time of his
submersion in the waters of Sunrise Lake.

Not a single word did he utter, but throwing off his coat, he made a
leap over the side of the boat, already slowing up as the power was cut
off.

"Frank's gone back after him!" cried one.

"And he'll get him, too," another hastened to say; for they understood
that when the leader of the team known as the "Bird boys" attempted
anything he usually got there, as some of them said "with both feet."

Meanwhile Frank was swimming with all his might toward the spot in the
foamy wake of the boat, where he knew the unfortunate Puss must be
battling for his life.

It seems strange that occasionally a boy may be found who has never
taken the trouble to learn how to swim. In the country this is a rare
occurrence; which would make the neglect of such an athletic fellow as
Puss seem more remarkable.

He was threshing about in the deep water like a cat that has fallen
overboard; and managing to keep partly afloat after a fashion; though it
would have been all over with him long ere the power boat could be
turned around and arrive at the spot where he struggled, gasping for
breath, and sucking in much water.

Frank was wise enough to understand that it is always desirable to
approach a drowning person from the rear, so that a grip may be taken
before the would-be rescuer's presence is discovered. Once let those
frenzied fingers clutch hold of him, and the chances of a double tragedy
would be good.

So Frank was keenly on the watch as he swam toward the splashing and
gurgling that announced Puss Carberry's fight for his life.

He could see him by now, and never would Frank be apt to forget the look
of absolute terror he discovered upon the agonized face of the
bully. Puss had detected the presence of some one near by, and was
trying to shout, as well as stretch his appealing hands out, though not
with much success.

He actually went under while Frank looked; and the heart of the would-be
rescuer almost stood still with a terrible fear that that was the end.

But he kept on, and in another moment a head once more bobbed up, with
Puss threshing the water frantically. Once he had gone down. According
to what most people said, he would possibly vanish twice more, and after
that never rise again.

If anything was to be done, there was no time for delay. Frank was
within ten feet of the struggling figure when it came up. He immediately
dove, and managed to rise to the surface behind Puss. Then, just as the
other was floundering beneath the surface of the agitated water again,
Frank caught hold of his sweater close to his neck, and held on with
might and main.

He had a serious job of it, for the half-drowned lad made a desperate
attempt to turn around, doubtless with the intention of throwing his
arms around his rescuer. This was just what Frank was desirous of
avoiding. He simply wanted to keep the head of Puss above water until
the boat could come and willing hands be stretched down to relieve him
of his burden.

So he kept treading water and fighting Puss off as best he was able. It
was no easy task, since he still had his baseball shoes on; and swimming
in one's clothes is always a difficult proposition. But Frank knew no
such word as fail and continued to strive, keeping one eye on Puss and
the other on the approaching power boat.

"Steady now, Puss!" he kept saying, again and again, trying to instill
some sense in the head of the frantic boy, who still believed he must be
going down again. "Keep your breath in your lungs and you'll float!
Don't kick so; I'm going to hold you up till the boys come. It's all
right, Puss; you're safe!"

All the same Frank was mighty well pleased when the launch did swing
close alongside and half a dozen hands reached out to clutch hold of
them both.

"Puss first, fellows!" he said, with a half laugh. "I can crawl in
myself, I guess." But they would not hear of it, so willing hands lifted
him up as soon as the other dripping figure had been deposited in the
bottom of the boat.

Frank made light of the adventure, after his usual style.

"Oh, come, let up on that!" he remarked, when some of the fellows were
patting him on the back and calling him a hero and all such things that
were particularly disagreeable to Frank. "It was just a cinch to me, you
know. I'm half a water spaniel, anyway. Besides, if it hadn't been for
the way I riled him, Puss wouldn't have fallen overboard. Drop it,
please."

By the time the boat reached the landing near the dock where the lake
steamer touched, Puss seemed to have discharged his cargo of water,
swallowed unintentionally.

He made his appearance, with several cronies clustered about him. Frank
was not the one to hold a grudge. Besides, he had come out of the affair
with flying colors and had nothing to regret. So he strode up to Puss at
once, holding out his hand.

Every boy on board crowded around, eager to see how the bully would
behave, for they knew his natural disposition and wondered whether any
sort of miracle had been wrought in his disposition because of his
recent submersion.

"I hope you're feeling all right now, Puss," Frank said, pleasantly. "I
wanted to ask your pardon for treating you so roughly; but knowing you
couldn't swim, I was afraid that if you closed with me we'd both go
down."

"But you struck me once right in the face, you coward!" exclaimed the
other, as he put his still trembling hand up to where a bruise of some
sort could be seen.

"Yes, I admit it," returned Frank, quickly; "and that was what I wanted
to apologize for. You grabbed me and it was the only way I could break
your hold. I've been told by life savers that often they have to strike
a man and knock him senseless to save themselves from being dragged
down. You must understand that it was no time to be particular. I had to
save myself in order to help you!"

The other stared hard at him. Evidently Puss had not yet entirely
recovered after his close call. At any rate it was positive that he
could not understand how he actually owed his very life to the speedy
action of this boy whom he hated so bitterly.

They saw him shake his head, much as a dog might that is worrying a rat.

"Well, you only undid your own dirty work. You pushed me in and then
you got cold feet. For fear that I'd drown and you'd be hung you jumped
in to do your usual grandstand act of hero! Didn't I hear these softies
calling you that right now? No, I don't want to touch your hand. Keep
your friendship for those who can appreciate it. There's a long account
between us that's going to be settled some fine day."

And with these ungrateful words Puss Carberry strode off the boat,
surrounded by his cronies, who were doubtless pleased with the course of
things.

"Well, did you ever hear of such base ingratitude in all your born
days?" exclaimed Larry Geohegan, making a gesture of supreme disgust.

"And to think of the skunk saying Frank pushed him in!" echoed Elephant,
"when he actually risked his life to save the cur. Ain't I glad now I
didn't carry out my first impulse and jump after Puss, even before Frank
went. Why, maybe he'd have even said I tried to drown him!"

The idea of that proverbial slow coach of an Elephant ever doing
anything on the spur of the moment was really too much for the rest of
the boys and a general roar went up. "Don't bother your heads about me,
fellows," remarked Frank, quietly, when the laughter had ceased
again. "That was just about the kind of treatment I should have expected
to get from Puss Carberry. Still, I'm not sorry I did it. Life would
seem very tame without that schemer around to try and liven things up
for me. But I hardly expected him to accuse me of pushing him in when
all I did was to step aside and avoid a blow at his hands. Forget it,
please."

He walked off with his cousin Andy, who had been boiling over at the
time the rescued Puss made his astonishing accusation.

"Wouldn't that jar you some now?" remarked Andy, after his customary
fashion.

"I suppose you're referring to the way Puss turned on me after I went
and got my baseball suit wet just to give him a helping hand?" laughed
Frank, good naturedly. "Oh, I don't bear any malice. Perhaps he was
still a little stunned by that knock I gave him. But I thought he was
going to get his arms around my neck, you see, and then it would be all
up with us both. It worked, too, for he was as limp as a dishrag from
that time on. Remember it, Andy, in case you ever jump over after Puss."

"Me after that snake? Why, hang it, I'd see him in Guinea before I'd
ever lift a hand to save him! I tell you I'd--I'd--" stammered the
indignant Andy.

"I don't believe it of you," declared his cousin, quickly. "You may
think you'd stand by and see him drown, but that's all gammon. I know
you too well to believe you're half as vindictive as you try to make
out. But did you hear what he said about going down there to South
America, visiting a plantation his mother partly owns and taking his
biplane along with him?"

Andy was all excitement now.

"Sure I did," he said. "And ten to one he learned somehow that we
thought of going down in that region for another purpose. It would be
just like Puss and that sneak of a Sandy Hollingshead to try and beat us
out. That fellow wouldn't mind a trip to the other end of the world if
he thought he could get your goat, Frank. He hates you like poison.
Pity you didn't feel a cramp just when you were swimming to him--not
enough to endanger your own life, you see, but sort of make you stop
short."

"Shame on you, Andy," remarked Frank. "I hope I'll always carry myself
so that I won't be afraid to look at myself in a glass. But what do you
know about that place--didn't he call it a cocoa plantation or something
of the kind?"

"Yes," replied the other moodily; "I was told that his mother owned
two-thirds of some such place along the Amazon or somewhere down
there. But let them go. It's a tremendous big country and there isn't
the least danger that we'll ever butt into them, if we _should_ decide
to take a run down."

"Still," observed the taller lad, thoughtfully, "you never can
know. I've heard travelers say that sometimes the world seems to be very
small; when you meet your next door neighbor on the top of some Swiss
mountain. Puss may know nothing about your plans and this is perhaps
only a coincidence, as they say. Since he has had such poor luck
getting to the top of our mountains around here he wants to try his hand
on those poor South American Andes."

Andy's father had been a professor in one of the colleges, who, having
taken up aeronautics, had made many balloon voyages in quest of
scientific information, so that his name had become quite famous. Then,
about a year before, he had been lost when attempting to solve the air
currents on the Panama Isthmus, where the government had thirty thousand
laborers digging the big ditch.

Nothing had ever been heard of the professor from the day he started
from the Atlantic side of the isthmus, intending to cross the mountains
and land on the Pacific beach. And it was becoming a positive mania in
the mind of Andy, who lived with his guardian, Colonel Josiah Whympers,
to some day go down there and follow in the track of his lost father, in
the hope of discovering his sad fate.

It was with this idea in mind that he had united his forces with Frank's
inventive genius and helped build the monoplane with which they had won
the race to the top of the neighboring mountain, during Old Home Week at
Bloomsbury.

And every day he was thinking more and more of what strange things the
future might have in store for him, if he ever started on that exploring
venture.




CHAPTER III.


SOMETHING ABOUT THE BIRD BOYS.

"How about coming over tonight?" asked Frank, as the boys halted at the
gate of Dr. Bird's place, where Andy had gone to get his wheel, since
he lived some little distance away.

"I'd like to first rate, Frank, because there are some things I want to
talk over with you. But I promised Colonel Josiah to get at his books
tonight and straighten them out. It'll take me all evening, I reckon."

"Oh, well," remarked Frank, "see you in the morning anyway. This breeze
will have worn itself out by then, perhaps, and if we feel like it we
can take a little trip somewhere in the 'Bug,' as you like to call our
dandy little aeroplane."

"I hope so," replied Andy, eagerly. "It's been some days now since we
were up, and I'm more than curious to find out if that new arrangement
of yours is going to help us any in getting a quick start."

"Does the colonel still persist in having old Shea sleep outside the
shed?" asked the other, as Andy pushed in to get his wheel out from
under a side porch, where he had thrust it before starting off to the
baseball game.

"Sure," came the reply. "When Colonel Josiah once starts on a thing it
would take an earthquake to stop him. I tried to tell him that there was
no danger of our monoplane being injured now that those two men who
robbed the jewelry store were locked up at police headquarters, waiting
for some formality to start them on the road to a ten-year sentence; but
he only shook his head and said Shea had nothing else to do and might as
well be earning his salt."

The incident to which Andy referred was related at length in the
preceding volume of this series, "The Bird Boys; or, The Young Sky
Pilots' First Air Voyage," and had created a ten days' sensation in the
quiet little lake town of Bloomsbury.

Two rogues had robbed the extensive jewelry establishment of
Mr. Leffingwell and carried off the loot in a couple of suit cases taken
from the store. Unable to get clear away on account of a quick chase,
they had hidden in the vicinity of the town. One of them, named Jules,
had been an aviator at some time in his near past over in France, and
learning that the Bird boys had built a monoplane, which was even then
ready for a flight, they had attempted to steal the same, with the
intention of giving their pursuers, who were hunting the woods for them,
the laugh.

But their well laid plans were spoiled through the vigilance of the Bird
boys and the quick wit of Frank in particular. The consequence was that
both men were eventually captured by Chief Waller and his officers and
still languished in the town lock-up, awaiting the day of trial.

"Oh, well!" laughed Frank, as his cousin wheeled his bike out to the
front gate, where he could mount better, "it makes mighty little
difference, because, from what I've seen of Shea, I imagine he sleeps on
his post. I'm glad we didn't let him inside, because, like all Irishmen,
he is fond of his pipe and might have set fire to the shed. It's
dangerous smoking where there's a lot of gasoline about."

"Of course we've got that Puss Carberry and his mean crony, Sandy
Hollingshead, to consider. They tried to injure our machine once and
might again, especially after what happened today," said Andy, throwing
one leg over his saddle and standing there a minute.

"Oh, I guess not, Andy. They understand that we're keeping tabs of that
hangar, with its precious contents. Besides, they've got their hands
full of other matters, if what Puss said about that big trip to the
Amazon country is true."

The other sighed.

"I only wish I was as sure of going down there as Puss seems to be," he
observed. "I don't know how it is, but something queer seems to be
drawing me that way. Day and night I have pictures rising in my
mind. I've read every scrap concerning the Isthmus and northern coast of
South America, until I guess I'm as well posted on such things as one
who had been there."

"Yes," said Frank, softly, "and I'm afraid you let your mind dwell too
much on that subject, old chum. It's more than a year now since your
father disappeared. And the chances of your ever finding what became of
him are like searching for a lost diamond in the sand of the
seashore. It's affecting your mind, Andy. You look all fagged out. I
wish you could cheer up and be something like your old self."

But the other only shook his head sadly.

"I don't believe I ever can, Frank, until I've had my chance to go down
there and make a good try to find all that is left of my poor
father. Just as you say, it seems almost silly to think that I could
ever succeed, but no matter, I've got it arranged in my mind and the
colonel is coming around slowly."

"Well," Frank hastened to declare, "you know if it ever does get to the
point that you do go down to make that search, I'm with you. My father
would never throw any obstacle in the way, I'm dead sure. And Andy, of
course we'd take our aeroplane along. Think how many trips we could
make in her over country that no one could ever penetrate on foot."

Andy was too full for further words. He simply turned and squeezed the
hand of his cousin; but the look of affection which he gave Frank told
what was in his mind just then.

Frank watched him go spinning along the road and then with a sigh turned
into the house.

The day had been replete with excitement for him. First there was the
keenly contested game with their rivals across the lake and a tie in the
ninth inning, which gave the Bloomsbury boys a chance to win out in the
tenth. His pitching had held the enemy safe, and in their half of the
inning Frank had made the hit that brought the game to a conclusion. As
a rule the home club took the last chance at the bat, but the Cranford
manager had chosen differently on this occasion, for some reason of his
own, and with disastrous results.

Then, on the way home, had come that little diversion aboard the launch,
when his old enemy, Puss Carberry, in attempting to strike him, had
miscalculated and gone plunging into the lake, himself being unable to
swim.

Frank had nothing to regret in connection with his leap after the
struggling lad and his subsequent saving of Puss. True, the latter chose
to crush down the natural spirit of gratitude that should have made him
accept the hand Frank offered later. But Frank felt that he could afford
to smile at such an exhibition of a small nature.

At the supper table his father and Janet, his sister, just home from
boarding school a couple of weeks back, plied him with questions
concerning the game. Of course, the girl had been present and had seen
her brother carry off the honors on the diamond; but there were lots of
things she wanted explained.

And before Frank knew it he was asked point blank what had happened on
the way across the lake, for Janet had been aboard another boat, it
seemed.

"Marjorie Lee told me she heard that you jumped overboard to save some
one, she didn't just know who?" was what Janet said, and the good doctor
pricked up his ears as he looked inquiringly toward the boy of whom he
was so proud.

Frank turned red and then laughed.

"Oh, pshaw!" he said. "I had hoped that would be kept quiet. But some of
the fellows like to talk too much."

"Who was it you jumped over after? They said you held him up until the
boat got around--that he could not swim a stroke, and must surely have
drowned only for your prompt action. It couldn't have been Cousin Andy,
because he can swim nearly as well as you. Tell us, Frank," Janet
persisted.

So Frank found himself compelled to relate the whole circumstance. In
his usual generous manner he tried to gloss over the conduct of Puss and
spoke as though the other had tumbled overboard during a little boyish
roughhouse business; but Janet knew of the enmity between the pair, and
she could read between the lines.

Frank spent a couple of hours after supper in poring over a book Andy
had loaned him. And it might easily be assumed that it had to do with
the birds, animals, fauna and inhabitants of that great country lying
north of the equator, down in Central and South America.

It was about nine o'clock when his father called to him. The doctor had
just come in from a few last visits and looked anxious.

"Frank, I'm in a peck of trouble," he said, with a whimsical smile, "and
I wish you could help me out, though I dislike putting you to so much
trouble."

"Oh, don't mind that, dad, one little bit; you know I'm only too glad to
be of any assistance to you. What's gone wrong now? Machine laid off
again and garage closed? But you won't need it till nine tomorrow, will
you?"

There was a world of affection in the very way Frank used that word
"dad." It might seem disrespectful coming from the lips of many boys,
but to the ears of the good doctor it was as sweetest music.

"That's the trouble, Frank. I do need some means of getting around
tonight the worst kind. Fact is the car broke down just as I got it in
the yard. Same old trouble, and will take an hour to fix it up. And all
at once it dawned on me that I had forgotten to take the medicine out to
Farmer Lovejoy, which I surely promised tonight. It lies under the seat
of the machine. Slipped my mind entirely when I was out. And Frank,
there may be a serious turn to that child's sickness unless that
medicine gets there within the next hour or so."

"Don't say another word, dad," declared Frank, jumping up and getting
his cap. "My wheel is in fine shape and with a good lantern I can make
the run in a jiffy. Only too glad to be able to help out. The packet is
under the seat in the car and you left that in the side yard? All right,
I'm off!"




CHAPTER IV.


A STARTLING DISCOVERY

It did not take Frank many minutes to get started on his little trip.

As he had said, his wheel was in good shape, with neither tire needing
any pumping up. And even his acetylene headlight had only to be
attached, which task took but a short time.

"I declare!" he exclaimed, as he rested his wheel against the gate and
turned back, "that would have been a rough joke on me if I'd gone
spinning off and only remembered after I'd almost got there that I
forgot to take the package of medicine out of dad's little runabout. So
much for having my brain full of that wonderful scheme of Andy's."

He found the medicine, and as the packet turned out to be small enough
to be stowed away in one of his coat pockets, Frank so disposed of
it. Then wheeling his machine out into the road he took a last look at
the lantern, to see that the water might not be dripping on the carbide
too rapidly to combine the greatest efficiency. After that he swung into
the saddle, starting off with the perfect freedom that proclaims the
rider a master of his wheel.

Once he passed out of town Frank made good progress. He had a ride of
several miles before him, ere he could expect to reach the farmhouse of
Jason Lovejoy, one of his father's oldest customers and friends.

There was no help from the moon, because the sky had clouded up and
screened the young queen of the skies. But Frank needed no other light
than the brilliant glow that spread out along the road ahead of him
coming from his lamp.

It happened that he passed the home of Colonel Josiah Whympers, the
retired and lame traveler, in whose care Andy had been left by the will
which his father had made before starting on what had proven his last
air voyage.

"Guess Andy's gone to bed," he mused, as he saw the house wrapped in
darkness, for it was now after half past nine.

Frank cast a glance back toward the big field where the shed stood in
which the great little monoplane, in which they had won their victory
during Old Home Week, was stored. But he could just barely make it out,
owing to the distance and the faint light of the moon coming through the
clouds.

Naturally the hearts of both lads went out toward the gallant aircraft
which had answered every call made upon it for speed and endurance. It
was equipped with an engine of the latest make, weighing only a third as
much as the average aeroplane motor and a triumph of modern scientific
discovery. Since the Bird boys had constructed that monoplane
themselves, after patterns obtained elsewhere, surely they had reason to
be proud of their work and the gallant victory which had come to them.

Frank pedaled on, thinking nothing of the trip. He was accustomed to
being abroad at night with his wheel, and, indeed, had taken many a
twenty-mile run by the light of his lamp alone.

What was there to fear? Bloomsbury was a peaceful community. Rarely did
anything occur to indicate that a spirit of lawlessness was
abroad. Occasionally the police had some trouble with wandering tramps,
but Chief Waller's strong point seemed to lie in that direction, and as
a rule hoboes gave Bloomsbury a wide berth. The word had gone out that
they made stragglers _work_ when caught there, and nothing could be
more horrible in the eyes of these "Wandering Willies."

After passing Andy's home it was not more than twelve minutes before
Frank found himself approaching the quiet farmhouse where he was to
leave the medicine.

The doctor had told him to ask a number of questions with regard to the
little sufferer, and Frank was well enough up in medicine to know what
to say when he learned how matters were going.

A big watchdog boomed his hoarse bark upon the night air, as Frank
dropped off his wheel at the gate where the mail box was fastened.

"Hello, Kaiser! Good dog! Don't you know me, old fellow? Come here and
be friends, Kaiser! It's all right! I'm coming in!"

Frank knew how to use a wheedling voice that a dog instantly recognized
as belonging to a friend. Besides, instinct doubtless told Kaiser that
any one who had evil intentions would come sneaking around and not in
this bold fashion.

At any rate, the big mastiff began to wag his tail, and though he still
barked, it was by way of a welcome now. Frank fearlessly opened the gate
and walked in. The guardian of the farm came up to him, sniffing, and
Frank, without hesitation, rubbed his hand over the shaggy head of
Kaiser.

So side by side they advanced to the house. Already a door had opened,
showing Farmer Lovejoy with a lamp in his hand. Evidently they had been
anxiously waiting for the coming of the good doctor, and were possibly
beginning to worry because he had failed as yet to show up with the
medicine he had promised.

"It's you, Frank, is it?" asked the farmer, as the lad drew near the
stoop.

"Yes, sir," replied the boy, cheerily. "His machine broke down and I had
to come on my wheel. But father said it was very important that you have
this medicine tonight. He expects great things of it by morning."

"Well," said Farmer Lovejoy, warmly, "that was right nice of you to come
all this way on your wheel, Frank. But I guess it's on'y what we'd
expect from Doc Bird's boy. I saw ye make that trip up to the top of
the mountain in your airship, Frank. I tell ye it was wuth seein'! Won't
you come in? The missus'd like to see ye."

"Why, yes, I will; because dad asked me to explain something to you and
also get some information about Sue. A few minutes will make little
difference," Frank said.

But, although he did not suspect it just then, even seconds came very
near being of the greatest importance.

Perhaps he spent all of ten minutes in the Lovejoy home and in that time
learned what his father wished to know. The old farmer came to the door
with him, shaking hands warmly.

"Once again I say I'm obliged to ye, Frank," he remarked, with feeling,
"for comin' away out here to fetch the medicine. It may be the means of
savin' our gal to us, who knows? But I've got faith in your father. If
anybody kin fetch our Sue around he will. Good night, lad. Kaiser, mind
your manners. This is one of the best friends we've got."

"Oh, that's all right, sir," declared Frank, quickly, as he patted the
shaggy head of the big mastiff. "We understand each other, don't we, old
boy? He knew my voice, because a dog never forgets a friend, and I've
played with him many the time. Good night, Mr. Lovejoy. Keep up your
spirits. Dad says Sue is going to get over this all right in a little
time."

Once again on the road he turned his face toward home. After all, this
six or seven-mile run was only a good touch of exercise, and he would
sleep all the sounder on account of it. Besides, Frank loved nothing
better than to do something for the parent who all his life had been so
indulgent to him.

As he pedaled along, keeping his eyes well ahead, so as to glimpse any
vehicle that might loom up in his path, he was thinking of what Andy had
in mind. While the project was as yet rather uncertain, Frank seemed to
feel that his cousin could never be wholly satisfied that he had done
his duty by his father until he had spent some time down on the Isthmus
trying to get some traces of the lost aeronaut.

"I reckon I ought to know something of Andy's persistence," he said to
himself, with a chuckle. "And now that he's got this bee in his bonnet
there'll be no peace until he tries the scheme out. Sure I'm with him
from the word go. It makes me shiver all over with expectation just to
think of what glorious times we two chums might have--hello! there's
something ahead, and I'd better slow up!"

It proved to be a farm wagon, pulled by two tired nags, and headed for
home, after a day in the town market. The driver was asleep on the seat,
leaving to the sagacity of his animals the successful navigation of the
road.

Perhaps some movement of the horses or else the bright light of the
acetylene headlight falling on his face aroused the man, for he sat up
as Frank was about passing.

"Hello! is that you, Frank Bird?" he asked, leaning forward to look
closer at the rider of the bicycle.

"Sure; just been up to your neighbor's, Lovejoy's, with some medicine
for his Sue," returned the boy, recognizing the farmer.

"How is the gal gettin' on?" called the other, over the canvas top of
his seat.

"Fine. No danger, dad says!" answered Frank.

"That's good!" he heard the sympathetic neighbor remark, as he moved on.

Five minutes later and Frank once more found himself approaching the
Whympers place. As before, the house was in complete darkness, as if the
inmates were long since abed. Frank knew that the old man kept early
hours, seldom sitting up, for he read much during the day, having
nothing else to look after.

Then, as was only natural, the eyes of the bicycle boy turned once again
with more or less affection toward the quarter where he could just dimly
make out the long, squat shed out in the field, in which the precious
monoplane was stored.

As he did so Frank uttered an exclamation of surprise.

"Why, there's a light over by the hangar!" he burst out. "Now, what
under the sun do you suppose that old fool of a Shea can be doing? Oh,
my! Look at the flame jump up! Why, as sure as you live I believe the
shed's afire! And I can see the figure of a man moving about. This is no
accident, but something worse! And it looks as if the little 'Bug' might
be going up in smoke in a jiffy unless I can sprawl over the fence here
and get on the spot mighty quick!"




CHAPTER V.


A WARM FIVE MINUTES.

"Fire! Fire!"

So Frank shouted, even as he jumped over the fence, and made a bee line
for the center of the big field, where the shed lay in which the
precious monoplane was stored.

He had hastily leaned his bicycle against the fence as he made the
plunge. Nor did he cease to let out constant yells while running across
the open as fast as his agile legs could carry him. Twice he tripped
over some object and nearly fell, only to recover himself and speed on.

As he ran he kept his eyes upon the low building beyond. In this manner
he plainly saw the stooping figure of a man or boy making off in a
roundabout way so as to avoid him.

Frank's heart was burning with indignation because of this dastardly
attempt to ruin the gallant little airship that had so nobly stood all
tests and proven itself a splendid piece of workmanship.

"Oh, the contemptible coward! I'd just like to chase after him and get
my hands on him once!" was the thought that passed through his brain.

But he knew he could not. The scoundrel, no matter who it was, must be
allowed to escape in order that he turn his attention to the burning
shed and try to save the airship from destruction. Once the fire got
inside, there was enough of the dangerous gasoline about to insure the
speedy burning of the whole flimsy fabric, all but the motor itself.

So Frank kept headed straight for the hangar, trying to shut out the
sight of that crouching, fleeing figure. He continued to lift his sturdy
young voice in repeated shouts:

"Fire! Fire!"

Those in the house must hear; yes, and the neighbors, too. He might not
be able to master the flames alone and single handed, and would need
help. Besides, it was only right that Andy, being part owner in the
monoplane, should be made aware of its sudden peril.

As he thus drew near the low building he saw that the fire had already
gained considerable headway, just as if the incendiary might have used
kerosene or some other inflammable fluid, to hasten matters.

Frank's heart grew cold as ice as he contemplated the rapidity with
which those hungry flames were crawling up the dry boards that
constituted the side of the shed.

But he did not lose his head in this sudden crisis. It was
characteristic of Frank Bird that, no matter what the emergency, he was
always cool enough to think out the proper thing to be done or else jump
at it through instinct.

And Frank had foreseen just some such possible need as this. He even
kept several buckets of moist sand handy, where it could be snatched up
at a second's warning, knowing that most fires can be smothered, when
quenching them with water is out of the question.

"The buckets!" he gasped, as he arrived close to the building, one part
of which was now fairly covered with the creeping tongues of ruddy
fire. "I must use them on it!"

He had to turn the corner of the shed to get to where they stood. And as
he did so he ran plump into a figure that was coming toward him. Just in
time did Frank dodge a big fist that shot out. And in that second he
recognized in the other Shea, the Irishman who had been hired to keep
watch of the shed.

"Hold on, Shea!" shouted Frank. "It's me, Frank Bird. Somebody has set
fire to the shed! Grab up a bucket of sand and carry it around here. We
can put it out yet if we're busy!"

Shea had evidently only been aroused from a sound sleep by the
approaching cries of the boy and was still in a daze. He had discovered
the fire, and hearing Frank running toward him, supposed that this must
be the one who had done the evil deed.

But he had sense enough to do as he was told now, snatching up one of
the sand buckets and following the boy. Frank immediately commenced
fighting the flames with a vim. He slapped the wet sand at the creeping
fire, and wherever it struck there seemed to come a quick abatement of
the conflagration. But it was by this time so extended that as fast as
he succeeded in knocking it out in one place it cropped up afresh
somewhere else.

His ammunition would not last if this kept up.

"Get busy, Shea!" he cried. "Find something and slap at the fire for all
you're worth! Fight it, man, fight it!"

As Frank happened to turn his head to learn what the other was doing he
saw something that made very little impression on his mind just then,
but which had considerable bearing on the matter later.

A light was speeding along the road, heading away from town, and Frank
realized that the firebug had seized upon his convenient wheel and was
making his escape.

Later on he might figure out the meaning of this movement. Just then he
really had no time to give it a thought, no matter if a dozen wheels
were concerned. The fire demanded every atom of his attention.

Shea did get busy. Once he became stirred up, and he proved a valuable
helper. He went for the flames tooth and nail, smothered them with his
coat, regardless of consequences, after he had slipped that article of
wearing apparel off; kicked and tore and fought until it became evident
that between them they were certainly making a decided impression on the
threatening conflagration.

All this while it seemed to Frank that his heart was in his throat. Not
so much because he feared that they would fail to gain the mastery over
the fire as that some spark might find ingress to the shed and happen to
alight upon a can of the dangerous gasoline.

If such a thing occurred he knew that it would be all over. The hangar
must be completely destroyed and, of course, their little darling
airship would share in its fate.

So, even though he saw the end of the conflagration in sight, Frank knew
he had no reason to breathe easily until every spark had been trampled
under foot.

By now he was conscious of loud shouts coming from points near at hand
and realized that doubtless Andy as well as others had been awakened by
the racket and were coming on the run to assist. Had the safety of the
airship depended on their reaching the shed in time, though, its chances
would have been next to nothing.

Frank was just stamping on what seemed to be the very last vestige of
the fire when Andy came galloping to his side.

"W-what's all this mean, Frank? Where in the wide world did you come
from, and who set our hangar afire?" he gasped, almost winded from his
exertions, for he had dressed in about a minute, despite his trembling
fingers, and was barefooted even then.

"Don't know who did it, but he ran off on my wheel a few minutes ago. I
was on the way home--carrying medicine to Susie Lovejoy. Saw flames and
gave alarm. Got here on the jump and we managed to get the better of
it. But it was a close shave, all right, I tell you, Andy!"

Frank himself had no breath to spare, nor could it be wondered at,
considering the recent valiant fight which he had made against big odds.

"So the ornery skunks _did_ try to burn us out, after all!" burst forth
the other part owner of the monoplane, bitterly. "Say, where was Shea
all this time? What use was he as a watchman?"

"He helped me good and hard at any rate. Only for Shea I'd never have
got the better of it, I'm afraid," said Frank, always ready to cover up
any little failing on the part of another, though never hesitating to
denounce his own shortcomings.

"But just to think of the meanness of it all," continued Andy, shaking
his head in the aggressive way he had. "That Puss Carberry ought to be
shut up behind bars, that's my opinion straight from the shoulder, and
if I could only find out for sure that he was in this I'd get Colonel
Josiah to prosecute him to the limit."

"But we have no proof that it was Puss," remarked Frank. "The fellow who
stole my wheel went off along the road _away_ from town. And he
went licketty split, too, as if he had business over in Shelby or
Newtown. Perhaps it was only a hobo. He may have started the fire by
accident, and was trying to put it out when I saw him first. Then, when
I shouted, of course, he had to scoot."

"What's this?" demanded Andy, kicking some object, and then seizing hold
of his foot, for he had forgotten that he had no shoes on.

Frank uttered a cry and picked it up.

"Look here, don't you recognize this?" he asked, as he held a can up.

It was Andy's turn to give vent to a low exclamation.

"Why, it's our kerosene can, Frank!" he said.

"That's what I thought. And it is kept on a bench just outside the
kitchen door, isn't it?" demanded the other, quickly.

"That's a fact. And neither of us ever brought it here. Shea, did you
ever see this oil can before?" and Andy dangled it before the eyes of
the watchman who had slept on his post.

"I niver did the same, sor," replied the man,
as he surveyed the can.

"Then that settles it, Frank. The mean skunk grabbed that can and
fetched it over here to spray the wall of the shed with oil and making
the fire jump."

"True as you live," said the other. "Do you know, I thought I smelled
burning kerosene. And that was why the flames kept crawling up
everywhere so fast. Well, it was a good job that we saved the place. And
ain't I glad I didn't wait just five minutes longer at Lovejoy's
place. Nothing could have helped then, and we'd just have to build
another airship. But here comes the colonel stumping along, Andy!"




CHAPTER VI.


IN SEARCH OF A CLUE.

"Heigho! what's all this fuss and feathers about?" demanded the old
retired traveler, as he came limping along, with his crutch and cane.

Several neighbors accompanied him, having been aroused by the clamor.

"Same old story, sir," remarked the disgusted Andy, still clutching his
bruised toe tenderly. "They've been trying to beat us one way, if they
couldn't another."

Frank gave him a nudge.

"Be careful what you say, Andy," he remarked. "There is no proof as yet
that any one we knew had a hand in this business. You may get in trouble
if you mention names offhand. Go slow now. We'll find out the truth
later on, perhaps."

So Andy, taking heed, managed to tell what had happened without directly
accusing any one. Nevertheless, it was not difficult for those who
listened to guess where his suspicions lay. And perhaps they thought,
after all that had occurred in the past, with the hand of Puss Carberry
moving the pieces on the chessboard, that Andy was justified in
believing as he did.

After a while the excitement died away. The boys had opened the shed
and made sure that no lingering spark remained to threaten their beloved
little aeroplane with destruction. But it was all right and they
feasted their eyes on it, as if they never before realized how precious
it had become.

"Getting to be a regular thing, seems to me, these night alarms, boys,"
remarked one of the neighbors, for not long before they had been aroused
in the middle of the night when the two jewelry thieves tried to steal
the aeroplane and were baffled in their design by the two boys, sleeping
at the time in the shed, so as to guard their flying machine.

"If one watchman ain't enough I'll get three--half a dozen if
necessary," declared Colonel Josiah, as he glared at the offending Shea
and pounded on the turf with his heavy cane. "But these lads are going
to be protected, if it takes my last dollar. I'll get a Gatling gun and
train it here, so we can blow the rascals to smithereens if they try
such a dastardly job again."

But everybody knew that the genial old colonel did considerable talking
and blustering, but was harmless withal.

Shea promised to remain awake the balance of the night. He even went to
the house and armed himself with a big horse pistol that the colonel
owned and which had many a story connected with its keeping company with
the traveler in foreign lands.

"Huh! I've got half a notion to camp right here again, like we did that
other time, Frank," said Andy, before they locked the wide doors of the
shed. "Here's my cot and blankets, you see, just as I left 'em."

"No need of that, Andy," returned his chum, smiling. "After all this
rumpus you couldn't hire that fellow to come back here tonight. He may
be ten miles away by now. Wonder if that's the last I'll see of my
wheel?"

"Now," continued Andy, "if you're addressing that to me I'd like to
prophesy that you'll find the bike somewhere off the road a mile or two
away, where the fellow pitched it when he concluded to make a sneak
_back_ to town."

"There you go, barking up that same tree again. I never saw such a
positive fellow as you are," declared the other, smiling. "Your name
ought to be Thomas, for you seem to doubt everything that you can't just
understand."

"Well, if not Puss, who, then?" demanded Andy, aggressively.

"I confess that I don't know at this minute," admitted Frank. "But I
hope to discover the truth in some way. Remember how that other time,
when some one tried to injure us by sneaking in here and cutting the
canvas wings of our monoplane all to flinders, I picked up a playing
card and we afterwards traced it to the owner?

"Yes," cried the other, instantly, "and wasn't that party Puss Carberry
all right?"

"It sure was," laughed Frank. "But forget this thing for now. Perhaps
tomorrow we may be able to find some clue that will tell which way the
wind blows--it might be the print of a shoe in the earth or something
like that. Lots of ways to pick up information, if only you keep your
wits at work."

"Yes," returned Andy, "and if it's Frank Bird who's doing the
thinking. But perhaps it would be silly in me sleeping out here tonight.
I'd better be traipsing back to bed right now, because, you see, I'm
only half dressed and it's chilly."

"Good. I'll see you to the house, because I've got to walk home, now
that my wheel has gone up the flume," remarked Frank.

"What's the matter with you using mine?" demanded the other. "That plug
you put in holds dandy, and there's nothing the matter with it right
now. Same old place, under the side porch here. Guess the lamp is on the
bum, but you hardly need that. If a cop holds you up, explain what
happened."

"All right, I guess I might as well ride as walk. But I hope I get my
wheel back. It's nearly new, you know, and cost a heap," Frank remarked,
as he dove under the stoop, to presently appear dragging the other
bicycle.

"Apply to Puss and Company for further information," called Andy,
holding the door open a crack to shoot the words out and then closing
it.

Frank, laughing at the obstinate ways of his chum, pushed the machine
out to the road and was soon moving along. Evidently he lacked the same
confidence in Andy's wheel that he felt in his own, for he made no
attempt to speed as he went toward town and home.

Fortunately he met no policeman, who might ask impertinent questions as
to just why he was riding after dark without a light. And reaching home
he found his father sitting up in his office waiting to hear his report.

Dr. Bird was quite satisfied with what Frank had to say in regard to the
condition of the sick girl. He knew that the boy was well up in
medicine, even though he had never tried to push him in the least. Frank
gave evidence of being what is known as a "natural born doctor," keenly
alive to everything pertaining to surgery. More than once he had set
broken limbs for dogs and cats and done it in a manner that aroused the
warmest praise from his father, who, deep down in his heart, knew the
boy had it in him to become a famous surgeon, if he kept along in this
path when he came to take up his life pursuit.

Frank believed he ought to tell about the dastardly attempt to destroy
the monoplane. And, of course, the good doctor, who always thought the
best of people, was horrified to hear his story.

He shook his head sadly after Frank had finished.

"I don't know what people are coming to nowadays," he remarked. "No
matter who did that mean act, it was wicked. Man or boy, he ought to be
severely punished for it. The rights of property seems to be getting
less respect every year. It puzzles me to lay the blame for this spirit
at the right door. But things were not so in my young days, Frank. We
live in fast times, my boy, fast times!"

Frank thought so himself, as he went off to his room. Imagine his
father, some forty years ago, ever dreaming of building an air-ship and
speeding through the upper currents, perhaps thousands of feet above the
earth, at the rate of a mile a minute! And yet that was what he and Andy
had been doing, thinking nothing of the feat, as they became accustomed
to its performance.

Fast times, indeed!

Frank did not allow the startling incidents of the night to keep him
awake. He knew just how to get a grip on himself and put all these
things out of his mind, once his head touched the pillow.

Time enough in the morning to begin worrying about that lost wheel and
trying to figure out who the firebug could have been.

At breakfast Frank had to go over the whole story again for the benefit
of Janet, who had heard enough about it from the doctor before her
brother came down to whet her appetite for more.

Frank could see that she shared the suspicions entertained by
Andy. Janet knew Puss Carberry of old and despised him most heartily. At
one time he had taken a great liking to Frank's pretty sister, but when
she learned what his nature was Janet had cut him dead on the
street. And from that day on she had believed Puss capable of almost
anything.

"Even after you saved his life yesterday, too!" she exclaimed,
indignantly.

"Hold on there, sis," cried Frank, laughing. "You're as bad as Andy, who
is ready to condemn on general principles. We haven't got a scrap of
evidence to prove Puss guilty. Just as like as not he would show an
_alibi_ if we accused him of it, and prove that he was at home all
evening. So please don't mention his name to anybody or I may get in a
scrape."

"But you're going to find out, aren't you!" demanded Janet.

"I surely hope to, and recover my poor bike in the bargain. Luckily I've
got my name and address scratched on the underpart of the frame, if the
finder only takes the trouble to look. And now I'm off downtown, to
speak to Chief Waller about it."

Ten minutes later Frank dropped off in front of police headquarters. And
no sooner had he alighted than the lad discovered that there was a buzz
of excitement about the place, for several men were conferring and the
chief himself seemed disturbed. He looked eagerly at Frank as the boy
came forward and started to relate what had occurred on the preceding
night out near the residence of Colonel Josiah Whympers.

Immediately the face of the chief began to light up and an eager glow
shine in his eyes. It seemed as though what Frank was telling must have
given him a connecting link that he had found himself badly in need of.

"Now we know where he went!" he exclaimed, calling to one of his
men. "Go out to Colonel Josiah Whympers', Green, and see what traces you
can get of him." Then once more turning to the astonished boy, he went
on: "You see, we had a jail delivery here last night. A desperate
scoundrel managed to slip away undetected and we only found it out this
morning. And the man who got out was your old friend, Jules Garrone, the
French aviator, who was caught by the help of the Bird boys and their
bully little aeroplane! Get that, Frank?"




CHAPTER VII.


ANDY RECEIVES A SHOCK.

"Then it was Jules who set fire to our shed!" exclaimed the boy,
astounded.

"None other, you may be sure," replied Chief Waller, nodding his head.

"And made off on my wheel?" continued Frank, beginning to grasp the
truth.

"That's just what he did," went on the official. "Found he couldn't
steal your aeroplane and was bound to lay his hands on something
belonging to the Birds that would carry him out of danger. Glad you
came, Frank. I'll just call up all the surrounding towns and ask if a
bicyclist has been seen there. I hope you can describe the wheel so they
might know it."

"Yes, I even know the number. Besides, I've got my address scratched on
the under-part of the frame. But whatever do you suppose Jules wanted to
set our hangar on fire for?" Frank asked.

"Huh!" replied the chief; "don't know, unless it was a spirit of
revenge. Some of these French rascals have the same nature as the
Corsican or the Sicilian and hug the idea of revenge to their hearts."

"Revenge!" Frank cried. "But when did we ever injure them? Oh, yes, I
forgot! We chased them off at the time they tried to steal our
aeroplane, and they even neglected to take those two suit cases of
jewelry with them, so the stolen property was recovered."

"Yes," the chief went on, "and that wasn't all, either. Remember that it
was you Bird boys who discovered that they were hiding in the old shack
deep in the forest. You saw them near there when you were sailing over
that region in your airship and reported to me. And so we surrounded the
cabin and nabbed our game. It may be they learned who gave them away,
and Jules, on finding himself at large, made up his mind to get even
before running off."

Turning to the phone on his desk the chief now started to call up
several of the neighboring towns. Some were only six or eight miles
away, while others might be double that and more.

Frank knew where the road ran that passed the Whympers place and when
finally the police head got Shelby he pricked up his ears. Immediately
he saw Chief Waller show signs of sudden interest. A smile crept over
his face as though he were hearing news that pleased him. Then he
engaged in a hurried conversation with the police official at the other
end of the wire, after which he turned to Frank.

"I think I've located your wheel, Frank," he observed.

"Over at Shelby, you mean?" queried the other.

The chief nodded in the affirmative.

"Yes, over at Shelby," he said. "It seems that early this morning a
wagon belonging to a countryman coming in to market was stopped by
something lying on the road. Getting down, the farmer found that it was
a man, badly injured, as if he had taken a header from a wheel. And,
indeed, a bicycle was found close by, with some parts of it damaged, as
if it had been run at full speed against a rock, sending the rider ten
feet away, where he landed on his head and was knocked out."

"Was it my wheel?" asked Frank.

"He described it, for the farmer brought both man and wheel to police
headquarters, and there can be no doubt but that it's yours. And the
unfortunate rider answers to Jules. Now, I'm going to get an automobile
at the garage and go over. If you want to go along I'd be glad to have
you, Frank."

"I certainly would," replied the boy, quickly. "I hope the poor fellow
didn't go so far as to break his neck. But let me go after a machine for
you, chief. I've got an errand at the garage anyhow, as my dad wants a
mechanic sent up to potter at his little runabout, out of commission as
usual. He's ordered a better car, you know, and is only waiting for it
to be delivered. Shall I go?"

"Yes. Tuttle will know which machine I generally use when on official
business, for you see the town pays the bill. Be back as soon as you
can, Frank."

"Yes, sir," replied the other, hastening away.

The mystery was now solved, and, after all, Puss had been proven
innocent on this last count. Frank laughed to think how amazed Andy
would likely be when he heard the news.

"I only hope he doesn't happen to run across Puss before I get a chance
to open his eyes," he was saying to himself, as he headed for the nearby
garage. "Because I really believe Andy is mad enough to challenge our
old enemy and throw the accusation in his teeth. Then there would be a
high old mix-up, with Puss in the right for once."

It did not take him long to deliver both messages. He saw a mechanic
start off to tackle the disabled runabout for the doctor, so he could
carry out his round of morning visits by ten o'clock. And then a
chauffeur ran a car out of the garage into which he invited Frank to
jump.

When they arrived at police headquarters the chief was awaiting
them. Evidently he was not at all averse to this delightful spin across
country on a fine July morning and with nothing to pay. Official
business might sometimes prove worth cultivating.

Presently they were off. Frank, of course, knew every rod of the way. He
had more than a few times made the trip over to Shelby on his wheel in
company with Andy. And since they had taken to the air they had looked
down upon that road for miles, as they whirled along hundreds of feet
up, discovering features about the landscape that they had never dreamed
of before they had this "bird's-eye view," as Andy delighted to call it,
playing upon their own name.

In due time they reached Shelby and drew up in front of the building
where the police held forth. The first one to meet their eyes as they
entered was a familiar figure seated in a chair and attended by a doctor
and a couple of officers.

"It's Jules, sure enough!" said Frank, as, despite the many bandages
about the head of the man, he recognized the dapper little French
aviator with whom he had had more or less trouble in the past.

And Jules grinned as he saw them. His spirit was not crushed, even
though it began to look as though he might be the football of fate.

"It ees ze fortunes of war, messiers," he said, wincing at the pain
speech caused him. "And after all, it was ze machine of ze young
inventor zat downed me. I am von lucky man not to haf been five thousand
feet up in ze air when it occur. Had eet been ze monoplane zat kicked
me, pouf! poor Jules he would haf been as flat as ze pancake. As eet is,
after I haf serve my time I am yet alive."

Frank found his bicycle badly damaged. In fact, the front wheel was
smashed beyond recovery, for it had been driven against some stone at a
tremendous pace. Strange to say, the lamp had gone through it all
without any apparent damage.

"A few dollars will fix it up, all right," he said, cheerfully. "And I
guess I ought to be thankful ever to see it again."

So he placed the wheel in the back of the big touring car. The doctor
announced that Jules might be moved without danger if they were careful,
and this Chief Waller promised he would be.

"You're giving us a heap of bother, Jules," he said, after the captured
rascal had been safety stowed away in the tonneau of the car, with the
chief beside him and Frank mounting to the front with the
chauffeur. "But this winds you up. I understand your trial comes off
tomorrow and you'll soon be snug in the pen."

"Zat was ze knowledge zat urge me to break out," remarked the prisoner,
blandly.

"Well," remarked the other, with a tightening of his lips, "we'll make
sure you don't get another opportunity, that's all."

Frank watched as they drew near the place of Colonel Josiah. He
anticipated that the prisoner would be eager to look across the field to
where the shed stood. Nor was Frank surprised to hear him give a low
cry.

"Eet is wonderful, ze luck zey haf!" Jules remarked, as he discovered
that the hangar had not burned to the ground as he expected, and after
that he relapsed into gloomy silence.

Frank had caught sight of Andy passing along the street ahead and
entering the Bloomsbury postoffice. So as soon as he could get his
broken wheel into the bicycle store, where he left orders for its being
fixed at once, he hurried off, in hopes of intercepting his cousin and
breaking the great news.

He was just in time to see Andy coming out of the building and staring
hard at something he held in his hand. Frank could see that it was a
letter and he also noticed that his chum was unusually pale.

"Now I wonder what he's got?" asked Frank, talking to himself, as many
boys often do at times. "Looks like a letter, too. Once in a while the
colonel asks him to go down when the mail comes in and see if there is
an important one for him, which he can't wait for the carrier to bring
out. And Andy has got one this time, sure."

A moment later and he came upon Andy, who at sight of his chum showed
signs of relief.

"I'm awful glad you came along, Frank," he said, seizing the other by
the sleeve; "I was at your house and they told me you had gone downtown
somewhere. Then, as the mail was in, I remembered Colonel Josiah was
expecting one of his letters from London, and so I dropped over. But
there was nothing for him. Mr. Guthrie handed me out this and said he
guessed it was for me. Oh, look where it is from, Frank! Do you
think--can it be possible that it means some news, after all this time,
from my father?"

Frank saw it was rather a bulky letter and that the postmark showed a
station in South America. Remembering all that had passed between them
in connection with this country he understood the cause of Andy's great
emotion.

"I was almost afraid to open it, Frank," said the other, brokenly.

"Well, do it now," remarked Frank, and Andy tore the end off hurriedly.

He appeared to read hungrily for a minute, and then gave a cry of
amazement.

"Oh!" he said, taking in a big breath, "how strange! how wonderful!"




CHAPTER VIII.


THE MESSAGE.

Frank Bird could restrain his curiosity no longer.

"What is it, Andy?" he asked, as he laid an affectionate arm across the
shoulders of his cousin.

The other turned his eyes upon Frank, and there was something in their
depths that stirred the other tremendously.

"Is it about your father, Andy?" he demanded, eagerness plainly showing
in his whole manner; for he understood what a hold the subject had on
his chum.

Andy nodded, and as soon as he could command his quivering voice, said:

"Yes, nothing more than a letter from the grave, I fear! See, Frank,
written in his own dear hand. Oh! to think of it, that at least three
months ago he was alive, even though a prisoner, the sport of fate."

"A prisoner!" echoed Frank, astonished. "Whatever can you mean? Did he
fall into the hands of some of those strange Indians we have been
reading about, who have their homes around the headwaters of the Orinoco
River in Venezuela?"

This time Andy shook his head in the negative.

"It is stranger than that--almost beyond belief!" he replied. "My poor
father has for months been imprisoned in a great valley, surrounded by
impassable cliffs. Don't you remember something of the sort occurred in
one of Captain Mayne Reid's books, where the young plant hunters found
themselves prisoners in that way? But here, Frank, look for yourself."

"Where does the letter come from, in the beginning?" asked the other,
quietly, wishing to advance by slow degrees, so that he could understand
everything.

"A town in Columbia, called Barranquila," replied Andy, readily
enough. "I'm not sure, but I think it lies at the mouth of the big
Magdalena River, and is upon the coast. You know I've just devoured the
map of that region for months, and every name is familiar to me."

"Besides this queer communication, which you say is from your father,"
Frank went on, "there seems to be another letter?"

"That is from Señor José Almirez. Read it, Frank, and you will begin to
understand."

The letter was in a crabbed hand, apparently unused to writing in
English, though grammatically correct. And this was what Frank saw:

"To Señor Andrew Bird:

"I received the enclosed from a correspondent and customer, one Carlos
Mendoza, located in the vicinity of Manangue, a town about one hundred
and fifty miles up-river.

"He is a grower of cocoa in the rich valley. I do not enclose his
letter, because it is written in Spanish. But it simply says that he
found the written communication close to his plantation house one
morning in April of this year. At first he could not understand how it
came there. Then, upon having the writing translated, he noticed that
the missive was attached to what seemed to be a little parachute, or
balloon, made up of a fragment of silk belonging to a balloon. Knowing
that I had spent several years in Washington, in the service of my
country, he finally concluded to send the same to me. I have the honor
to transmit it to the address given in the communication.

"With respect, and expressing a willingness to help you all I may, Señor
Andrew Bird, believe me to be most sincerely yours,

"José Costilena Almirez."

Frank read this amazing communication, and then turned to stare at his
cousin.

"No, don't stop yet!" exclaimed the trembling Andy. "Read the other, the
missive that Carlos Mendoza picked up on his cocoa plantation, in the
valley of the Magdalena River."

And so Frank again turned his attention to the enclosure that had been
sent on by the friendly merchant of Columbia.

It seemed to be a sheet of thin but pliable bark from a tree, and in
some respects reminded Frank of birch bark, which he had often used in
lieu of paper, when in the woods. The juice of some berry had afforded
ink; and doubtless the college professor had easily made a pen from a
bird's quill. And this was what Frank read, a small portion of the
communication being missing, as though it had received rough usage
somewhere, en route:

"Whoever finds this, I pray that it be forwarded to Andrew Bird, in the
town of Bloomsbury, State of New York, U. S. A. In my balloon I was
carried away by a sudden storm while crossing the Isthmus of Panama. As
near as I can calculate I was swept some three hundred miles, more or
less, in a south-easterly direction, much of the time above the
clouds. Then something happened, and I felt myself falling. Giving
myself up for lost, I awoke from a swoon to find myself in the branches
of a tree, with the wreck of the balloon near me. A merciful Providence
has saved my life, but I fear only to prolong my agony of soul. For
months now I have been a prisoner in a remarkable valley, a sink-pit,
enclosed by inaccessible cliffs. Many times have I struggled to climb to
their top, but only to meet defeat.

"All this time I have sustained life by means of fruits that grow in
abundance in this tropical valley. In the hope that I may manage to
communicate my horrible condition to the outside world I have made
scores of small parachutes, and when the breeze at the top of the cliffs
appeared favorable, send them up by means of hot air, each carrying a
message to my son. God in His infinite wisdom only knows if one of these
will ever reach him. I shall continue to have hope, and sustain life as
long as my mind remains--

"Professor Philip B----"

When he had finished this astonishing document Frank turned to his chum.

"Oh! what a remarkable thing! I never heard its equal in all my life. To
think that your father has been alive all these months, though a
prisoner in that cliff-bordered valley! But Andy, don't you see that
now nothing is going to keep us from going down there, and finding him?
Here is the clue you wanted, only instead of discovering his sad fate
you are going to rescue him, and bring him home again!"

They reached out and gripped hands. There was something in that act to
stamp the more than brotherly feeling existing between them.

"Do you think we could do it, Frank?" exclaimed Andy, more than ever
willing that his clear-eyed chum should take the lead in this most
eventful moment of his whole young life.

"Sure I do," answered the comforter, readily. "Didn't we conquer one
battery of cliffs that were said to be insurmountable, when we sailed in
our dandy little monoplane up to the crown of Old Thunder Top, and
snatched that silver cup for a prize? Make up your mind, my boy, that
that was just meant to get us in practice for better things. The time's
come for us to show what we're made of. And instead of a silver cup, the
prize this time will be--"

"My father's life!" murmured Andy, tears in his eyes, as he again
squeezed that faithful hand which held his so firmly.

"That's right," Frank continued. "We can go straight to this fine
Spanish gentleman, Señor Almirez, and get all the points he knows. From
there we'll get up-river to this valley town and visit Carlos Mendozo on
his cocoa plantation. Depend on it he'll be able to set us on the track,
somehow or other."

"Oh! it seems like a strange dream," said Andy, as he raised the piece
of bark to his young lips, and passionately kissed it, regardless of the
fact that some one passing the post office might notice him.

"Well, you want to wake up right away then," remarked Frank, smiling,
"because we've just got to get a hustle on us, if we're going to start
on this wonderful trip. Here's where our aeroplane is going to help us
out. Just imagine how we can pass over regions where it would be next
to impossible for us to navigate on foot--mountainous country, tropical
valleys where wild beasts roam and poisonous snakes abound; and jungles
where the natives have to cut a passage foot by foot, I understand, with
their _machetes_. And to think that we can sail freely over it all,
looking for that spot where that bark letter came from."

"Come, let's go home!" exclaimed Andy. "I'm sure Colonel Josiah will be
tremendously interested in what we've learned. He'll be the most
disappointed man in the whole U.S. just because he's so crippled that he
can't go along. For many years he's traveled in every country under the
sun. Perhaps he might tell us more about the interior of Colombia than
we know right now."

Accordingly they hurried away. Frank came near forgetting the news he
had been bearing at the time he met his cousin. But then, that was
hardly to be wondered at. The capture of the escaped robber was of minor
importance when compared with this wonderful business connected with
Professor Bird.

And just as Andy had said, Colonel Josiah _was_ tremendously interested
when he heard about it, and with his own eyes looked upon the letter
that had come from a living tomb.

"Somebody pinch me," he said, looking at the boys almost helplessly. "I
surely must be asleep, and dreaming this. It seems too strange to be
true. Philip alive all these months, and in that terrible situation,
while we were enjoying the good things of the world up here. It is
monstrous! You must go down there with as little delay as possible,
Andrew. Who knows but what it may be your blessed good fortune to rescue
your dear father, and bring him back with you. Money--all you need; and
the prayers of an old man go with you."

"But think," said Andy, uneasily, "this was written three months
ago. What may not have happened in all that time? There must be beasts
in that sunken valley, and doubtless many poisonous reptiles. Perhaps--"

"Hold on!" cried Frank, interrupting him, "don't you go to imagining all
sorts of terrible things. He had been there at least nine months
already. Nothing had happened to injure him. He does not even hint at
such a thing; but says he means to sustain his life as long as he
retains his proper mind. Your father was not in the least like you,
Andy. He possessed a wonderfully well-poised mind, and laid out his
plans with deliberation. Believe me, the chances are ten to one he is
still there, and waiting. We are going to find him. Don't allow any
other idea to take possession of your head. Find him, do you hear?"

Of course that sort of talk had its effect on Andy, and he braced
up. They began to make preparations and plans without delay. The
monoplane was taken apart, and carefully crated. Then Frank ran down to
the city and returned with several duplicate parts, secured at an
aeroplane agency he knew of, and which would come in handy in case of an
accident in that strange country, where they must depend entirely on
themselves.

For two days there was a tremendous lot of bustle around both
homes. Dr. Bird had no longer any valid excuse for refusing Frank
permission to go, since it was a mission of mercy that beckoned the boys
on to that South American mountainous region. Besides, he had always
been very fond of his elder brother, who had done so much to make the
name of Bird famous, in college and out; even though the professor had
thought best to make his old friend, Colonel Josiah, his boy's guardian
instead of the physician.

The aeroplane had been shipped to New York, to be put upon a steamer
sailing for Maracaibo, in Venezuela, and which they expected to take
also. From this port they would have to make their way to the mouth of
the Magdalena River by means of some smaller craft. But with virtually
unlimited means to back them, the boys did not fear but that they could
overcome any difficulties that might arise in their path. Indeed, Frank
had a disposition that would never allow anything to balk his plans, if
it were at all within the power of human nature to accomplish results.

The last thing they heard, just before leaving Bloomsbury, was that Puss
Carberry and his crony, Sandy Hollingshead, had gone away, taking their
biplane along; and it was said that they expected to do wonderful stunts
with their airship somewhere in the South. But our two boys were too
deeply interested in their own fortunes to give more than a passing
thought to the flitting of their rivals. Besides, it would not seem
that there could be one chance in a thousand that they would ever run
across Puss and Sandy in all that great country, lying south of the
Caribbean Sea, and north of the mighty Amazon.

And one morning Frank and Andy said goodbye to those whose best wishes
were wafted after them, taking train to New York City, so as to go
aboard the steamer, that was scheduled to sail that P.M.




CHAPTER IX.


UNDER TROUBLED SKIES.

"Oh! how glad I am to think we've arrived at last!"

Andy uttered these words as he stood at the rail of a small but staunch
steam yacht, of rather ancient vintage, that he and Frank had leased
when arriving at Maracaibo, the city on the bay of the same name, from
whence so much of Venezuela's coffee is shipped to the States.

It had belonged to some Englishman who, becoming stranded at this South
American port while on a globe circling trip, was forced to let it go;
and the agents gladly secured a crew for the adventurous young
Americans, who were bound up the Magdalena River for some unknown
purpose.

"Yes," observed Frank, who leaned on the same rail close beside him,
"there's the town of Barranquila, all right. We've navigated the five
hundred miles in this little steam craft" with only a few break-downs of
the machinery, and just two days' delay. And the second step on our
journey comes to a close."

"The third ought to take us to that valley town up the river; ain't I
right?" asked the anxious Andy.

"Sure. As near as I can make it, Magangue must be not over two hundred
miles upstream. With good luck we can cover that in a couple of days,"
returned Frank.

"But why do you say good luck?" demanded his cousin, suspiciously.

"Oh! well, we are now in the land of tomorrow, you remember," laughed
Frank.

"You mean where they put off everything they can, saying 'no hurry;
plenty of time, señors all; the world was not made in a day'? Is that
it?" Andy went on.

"Partly. I was also thinking of another thing," admitted Frank.

"Yes, and I bet I can give a mighty good guess what it is, old fellow."

"Perhaps you can," Frank said, a little gravely. "Suppose you spout it
out."

"You've been pondering on what old Quito was telling us, in his broken
English, about this little revolution that has been slumbering around
the region of the Magdalena River of late. You have a hunch that we may
just be unlucky enough to run across some of those ragged chaps, who
want to upset the present government of Colombia, and seat some old
ex-president fossil in the chair again."

"Anyhow, you're a fine guesser, Andy," admitted Frank.

"Then that's what was on your mind?" asked the other. "I've noticed you
frown a whole lot lately, which is unusual for my cheery pard, Frank."

"Oh! well," observed Frank, calmly, "I acknowledge the corn. I was
wondering whether we might be troubled by any of those fellows while we
were navigating this river. I hope they'll just let us severely
alone. But you know, Andy, just as Colonel Josiah warned us, these
Colombians don't have any too much love for Yankees, ever since that
Panama rebellion, when, as they believe, our government openly assisted
the people of the Isthmus throw off the Colombian yoke, because we just
had to control that strip of territory for the canal."

"But why should the revolutionists want to stop us?" insisted his
cousin. "We are here only on a private quest. We seek no gold mines or
cocoa plantations. Our only object is a mission of mercy. And besides,
if these men are in open rebellion, they ought to be glad to see anybody
that their government detests, Yankees or not."

"Well," pursued Frank, with a cautious glance around, "I was thinking
that some of the people in Maracaibo took altogether too much interest
in our little monoplane. A lot of dark-faced men hovered around, and
asked many questions. They have heard and read much about the wonderful
things being done today in aeronautics, but have seen little or
nothing."

"Frank, that's so!" exclaimed Andy, quickly. "Please go on. You are
gripping my attention a heap, I admit. Tell me, do you suspect that some
of those same chaps may have been Colombians?"

"I'm dead sure of it, and more than that, old Quito gave me to
understand he believed they were connected with the junta that was
pushing this new revolution in Colombia."

"Yes?" Andy said, in a way that plainly invited further explanation.

"Stop and think," Frank continued. "Suppose now, they conceived the idea
that it would further their forlorn cause a heap if they only had such
an airship, and could threaten to drop all sorts of bombs into the camps
of the government troops!"

"Good gracious! I suppose that is so. I never thought of that, Frank!"

"You know how nervous and excitable these people are? Don't you think
they'd give the government the worst scare it ever had? And couldn't
they make almost any sort of terms of settlement?" Frank demanded.

"Yes, that's true. Then you imagine those fellows may have planned to
somehow steal our aeroplane, and that they've sent word ahead to their
friends along the Magdalena to look out for us?" was Andy's startling
question.

"Partly that. But don't you see, Andy, the little monoplane would be
utterly useless to them unless they had some one who knew how to run
it?"

The other gave utterance to a low whistle, just to indicate how his
feelings had been stirred.

"You mean they might try to capture _us_ in the bargain, and force us to
operate the aeroplane? But suppose we did, what would hinder our just
sailing away, once we got up in the clouds? Tell me that, Frank?"

"Oh! well, I'm not looking that far ahead," smiled the other. "Possibly
they might only let one of us go up, keeping the other as a hostage. Or
perhaps, there might be a fearless revolutionist officer aboard with
that one, sworn to shoot at the first sign of treachery. But don't let
us cross a bridge until we come to it."

"That's right. We don't want to fall into the hands of any ragtag
revolutionists, and we won't! We've got our work laid out for us, and
nothing must stop us. All the same I'm going to keep an eye on that
precious case in which our aeroplane is boxed, as well as the
engine. And Frank, I'm carrying the little shooting-iron Colonel Josiah
gave me as a parting present."

"Ditto myself," replied the other, in a low tone, as one of the crew
happened to draw near, while getting ready to make a landing at the
wharf. "He told us that down in this country it paid to be ready for
trouble; though I keep hoping we're not going to have anything of the
sort."

It was toward noon when they steamed up to the town that nestled near
the mouth of the great Magdalena River. Of course it was hot, for the
season of the year made that a foregone conclusion; but both boys were
dressed in suitable attire, and also wore pith helmets calculated to
allow a current of air fan the head.

Andy was shivering in a mixture between hope and fear. In this city they
would meet the writer of that pleasant letter, Señor José Almirez. What
if he had received further intelligence from the correspondent up-river
since the time he had mailed that letter? What if some terrible news
awaited the coming of the daring young Yankees, who had ventured to this
faraway country, bent on solving the mystery connected with the long
absence of Professor Bird?

But, as usual, it was Frank who buoyed his spirit up. There never was a
chum more devoted to the interests of his friend. Andy would long since
have succumbed to his fears but for the cheery words of the other.

It was said to be the rainy season in this country that lay in the
tropics. Up on the high mountain peaks lay snow the year around; but in
the low lands, and along the valleys and sides of the uplifts, they
could grow coffee, cocoa, bananas pineapples, oranges and all manner of
similar products.

A small crowd gathered at the wharf to see the little steam yacht come
in. Perhaps the former English wandering owner had been here before, and
some of them even recognized the vessel.

Scowls greeted her passengers when it was discovered that they were not
English but Americans. Frank and Andy paid little heed to these
frowns. They did not mean to leave the boat, if so be it were possible
to have Señor Almirez come aboard. And for that purpose they had written
to him ahead of time, telling him how they expected to reach Barranquila
about a certain date.

Several breakdowns of the engine had delayed them, so that they were
even now two days behind time. On this account, as well as through
prudence, they meant to stop here as briefly as possible.

Immediately their purser went ashore to make inquiries, and purchase a
lot of fruits that could be taken on the river voyage; though for that
matter they might expect to get anything they wanted at various villages
along the route.

Frank was looking the crowd over closely.

"I think I see him, Andy," he remarked, presently.

"You mean Señor José?" asked his cousin, eagerly. "I've been watching
that middle-aged gentleman who seems to be pressing close in on the
flank of the crowd. There, see, he is speaking to Manuel, our purser,
now, asking him some question. He looks up here at us; yes, and waves
his hand, with a smile! That must be Señor José, all right, Frank."

"I'm going down to meet him, to fetch him aboard," declared Frank, after
both boys had answered the signals of the dark-faced gentleman in the
white linen suit, and who was also wearing a Panama straw hat.

Three minutes later and Frank reappeared, having the other in tow.

Just as both of them had suspected it was Señor José. Receiving their
communication from Maracaibo, he had been on the watch.

"And he tells me, Andy, that there has been no new development since he
wrote. So that fear of yours must be set at rest. Just depend on it,
we're in this game to win out, and your dear father is going to be
found," Frank went on.

Presently they were deep in conversation. The boys found Señor José a
very intelligent gentleman indeed. He had spent some years in Washington
in connection with the embassy of his government, so that he not only
spoke and wrote English well, but had a high opinion of Americans;
something that the vast majority of his fellow-countrymen failed to
acquire, being possibly fed on stories that may have had their inception
in German or English trade sources.

From him Frank extracted all the information he could concerning the
wonderful country lying between Magangue and the Isthmus of Panama,
covering possibly some three hundred miles. It was little enough. Most
of it, he declared was a _terra incognita_, being utterly unknown land.

"But," continued the obliging señor, "you will certainly be able to
learn more concerning this when you see my fellow-countryman, Señor
Mendoza; for all his life has he lived there at Magangue, and surely he
must know something of that country to the south."

"We shall leave here with as little delay as possible," observed
Frank. "I have sent our purser, Manuel, to comply with the custom
duties, and secure us a few supplies. When he comes aboard again we
expect to start."

"It is just as well," remarked the other, significantly, and seeming to
be relieved. "Because, there is an uneasy feeling in Barranquila just
at present. Agents of the revolutionary junta have been here. They are
very active. And from secret sources I happen to know that they are
aware of the strange cargo you are bringing with you."

"You must mean our aeroplane, Señor?" remarked Frank, quickly.

"Si, Señor Bird," the other continued, nodding his head. "It has become
known that the two young Americanos are of the new and wonderful
aeronauts, with whom nothing is impossible. And if you remained here any
length of time I fear lest even my government might seek to find some
excuse for appropriating your little airship. The talk is all in that
direction now. Colombia is ripe to take a forward step, and have an
aviation corps."

"Well," said Frank, "under the circumstances we would seriously object
to having our monoplane confiscated now, because upon it we depend
wholly in our search. But I thought you were perhaps about to warn us to
look out for these revolutionists while passing up the river."

"It would be wise, Señor," observed the amiable Colombian
ex-diplomat. "They have agents here; and I happen to know that one is
even now on the wharf, observing. Possibly he seeks to communicate with
some spy who chances to be a member of your crew. So you see, it must
pay you to be always on your guard, and prepared!"




CHAPTER X.


NIPPED IN THE BUD.

"There comes Manuel!" remarked Andy, after they had been nearly an hour
talking on the deck of the little power boat.

"Yes," remarked his cousin, who was also on the watch, "and trailing
behind him I can see several native carts containing fruits and new
supplies. Manuel surely means that we shall not go hungry while on the
river."

"Then I shall be going, my friends," said Señor José. "I have told you
all I know. I have warned you to beware of the revolutionists along the
river bank. I have even given you a hint that to delay longer in
Barranquila might endanger your enterprise; since the government is just
now very anxious to acquire such wonderful modern agents of warfare, as
your aeroplane. It only remains to shake your hands, both,
_amigos_, and wish you every good fortune your valor deserves."

They squeezed the hand of the fine old Colombian gentleman with
vigor. Never would Andy forget how he had spoken concerning his interest
in the sacred duty that had brought the son of the missing aeronaut to
his country.

Frank had given strict orders that none of the crew should go ashore,
and also that no strangers be permitted to board the craft while they
lay there at the old wooden wharf.

"But," said Andy, when they were speaking about this matter, as
preparations began to leave the port, "that hasn't prevented the crew
from holding an animated confab with those ashore. There has been a
constant jabbering and laughing between our fellows and those others."

"Yes," admitted Frank, "and I've seen several of the crew talking
mysteriously with some of those chaps. I wish now the señor had thought
to indicate which was the secret agent of the revolutionists he saw on
the dock. But all the same I've marked the two fellows I suspect, and
I'm going to keep a close eye on Enrique, and the little fellow with the
quick motions we call 'Cospita,' because he's forever ejaculating like
that."

"And if you find out that they're meddling with the boxes?" asked Andy.

"H'm! I guess it'll be a bad day for Enrique and the jumping-jack,
that's all," laughed his cousin. "But there goes the cable, and it looks
like we might be off at last."

"I'm not sorry, for many things!" declared Andy, with a sigh of positive
relief. "The good señor got me scared by what he said about his
government wanting just such things as our little 'Bug'; and that the
officials might have orders to find some sort of ridiculous excuse for
grabbing it."

"Same here," admitted Frank. "In fact, that bothered me a whole lot more
than the chances of trouble along the river from the boys who want to
get their man seated in the president's chair, where he could hand out
the loaves and the fishes. We can resist them, and be backed by
authority; but if the government officers once took us in we'd have to
give up our job. And that would break your heart, Andy."

"Yes," said the other, drawing a long breath, "I'm afraid it
would. Listen! There goes the whistle. I told the pilot not to make more
fuss than he could help when we drew out."

"Which was quite right. I'm watching that little chap, Cospita. See him
wave his hand to some one ashore? Yes, and that surely looked like a
signal the fellow returned. We are going to have trouble with that boy
yet, Andy."

"Well, that will be bad for Cospita," was all the other remarked; for he
was eagerly watching the growing space between the boat and the shore.

"Look, Frank," he remarked, after a little time had elapsed, "as sure as
you live, there is an officer in uniform just arrived on the dock, and
backed by a squad of soldiers! He seems to be surprised at discovering
that we have gone! Now he beckons, and waves his hat! Listen to him
shouting something in Spanish through his hands. I guess we didn't get
away from Barranquila five minutes too soon!"

"It looks like it," said Frank, grimly. "But we've complied with the
law of the land, and nothing short of a cannon could make us turn back
now. All the same, I'm going to the pilot house, and keep an eye on
Felipe. I think he's trustworthy; but an ounce of prevention is better
than a pound of cure always."

"Good for you!" Andy shot after his departing chum; though he himself
remained there by the rail, watching what took place ashore.

Frank quickly entered the pilot house. Here a dark-faced, middle-aged
man handled the wheel. Frank immediately noticed that he was listening
to what the gold braided officer ashore was shouting angrily. He also
looked a bit troubled.

"What does he say, Felipe?" demanded the young aviator.

"He commands us to return, señor," replied the other.

"Well, pay no attention to him, Felipe. We have complied with all the
regulations and red tape necessary. The American consul will back us
up. It is your business to simply steer this boat up the river until we
arrive at Magangue."

"Si, señor. But when I return they will surely make the trouble for me,"
replied the pilot, shrugging his narrow shoulders.

"Not at all, Felipe," declared Frank. "You can swear that we made you
do as we wished; that you dared not turn back, since your life was in
danger. We stand ready to shoulder all the blame there is."

The dusky face of the old river pilot, whom they had fortunately run
across in Maracaibo, became wreathed in a smile.

"Perhaps the young señor would not mind showing the Capitan?" he
suggested.

Frank grasped his meaning; and pretending to scowl darkly, he drew out
the revolver which Colonel Josiah had made him promise to carry while
down in this explosive country.

"Now, Felipe," he said, as he clapped the weapon deliberately against
the head of the pilot, "your gay Capitan can easily see what I am doing,
and will understand what it means. You keep right on up-river; and if
you dare disobey it will be bad for you, Felipe!"

The shrewd old pilot tried to smother an expansive grin as he replied:

"Si, señor, I am in your hands; do with me what you will. I dare not
refuse longer. See, I have made one effort to turn about; but you
threaten, and I give it up. He no longer calls. He knows old Felipe is
powerless. It is well!"

Frank stood by him until the wharf was dimmed by distance. Then he
hastened to rejoin his cousin and chum, who was mightily pleased to hear
all about it.

"Do you think they will chase after us?" queried Andy, still worried.

"Oh! I guess not. It isn't so serious as all that. They know they can
get us when we come down the river, no doubt," replied Frank,
carelessly.

"Then I'll care precious little what becomes of the Bug," observed Andy,
with a sigh of relief.

"I suppose you mean that by that time you'll either have found your
father; or else given up the search as hopeless. Is that it, old
fellow?" Frank asked.

"Yes, one or the other. And now, we've got time to remember the other
warning good old Señor José gave us."

"About the revolutionists trying to stop us on the way and get our
cargo? Yes," Frank went on, "that must be on our minds constantly. I'm
going to talk with old Felipe about it soon. I have a hunch that he can
be depended on to back us up, for he's got a grudge against the man
these fellows want to send back into the presidential chair. Señor José
told me Felipe lost all his family through the persecution of that man
and his party."

"A bully good thing to know," assented Andy. "For we can be dead sure of
Felipe all the time; and through him get pointers about the rest of the
crew. There are a few goats among the sheep, and when we make sure of
it, I'm just going to pay them off, and chuck them ashore in any old
place."

"Now that's what I call a clever scheme," Frank declared. "They would
have no kick coming, because, you see, no Spanish American could ever
complain of getting his wages without having to do any work!"

"I guess not," Andy remarked, grinning assent.

Upon further conference it was decided to divide the day and night into
watches, so that one of them could be on deck and alert all of the time,
while the other secured some sleep.

Treachery, they knew, would be likely to crop out during the night
time. Those on board may have found some means of telling their
confederates ashore about what time the boat would reach a given
point. And by means of some native method of telegraphing, such as by
means of wigwag flags, or "smokes," the news could be hurried up the
river much in advance of the vessel that was butting against the strong
current of the swollen Magdalena.

Then Frank went forward to have a long talk with the trusty pilot. He
took Felipe into his confidence, telling him for the first time all
about their sacred mission to this region of Colombia. And in this way,
as well as by promising to double his regular wages, Frank quite won the
old fellow's heart.

In return Felipe was able to give his employer considerable valuable
information connected with the crew. Frank mentioned no names, and hence
he was satisfied that he had made no mistake in his calculations, when
among the list of "suspects" given by the pilot, both Enrique and little
"Cospita" were included.

"We must get rid of them both as soon as possible," he announced. "So
just before night sets in, draw the boat to shore near some village or
town. Then I shall pay both men off, get their signatures to the fact,
and insist on their going ashore. Meanwhile, as you find opportunity,
post a few of the faithful ones to the fact that we suspect them of
being insurrectoes."

Felipe declared that the idea was superb. He was growing more and more
fond of these venturesome young Americanos, who were so generous, so
brave, and who had come all this great distance, actuated by such a
noble purpose. So many a man may easily feel when his salary has been
unexpectedly doubled.

During the balance of that afternoon the two young aviators continued to
alternately sit upon the deck, and wander about the boat, watching
things. Frank had the precious aeroplane locked up in the spacious
lazerette, which being also used as a storeroom for extra supplies, that
the circumstance need not be looked upon as singular.

"I'm determined that no ill may happen to that machine, if I can help
it," he said to his chum, when speaking of what he had had done.

And Andy, of course, fully endorsed his course.

So the sun began to draw closer to the western horizon, represented by
the distant mountains where the chief inland town of the province,
Sabanalarga, lay.

Felipe had spoken of a place on the eastern bank of the river, where
they could draw in, and put the two suspects ashore. And Frank told Andy
to back him up in what he was about to do.

"There's the town ahead, only a little place, but it answers our
purpose, for they can never say we deserted them in the howling
wilderness," and Frank, who had been counting out some money, started to
make his way down to the waist of the vessel, where most of the crew had
gathered, wondering what the object of the landing might be.

Enrique and "Cospita" were surely very much astonished and alarmed when
told that their services were needed no longer--that it was ascertained
they were carrying too many men; and also that they were to receive full
pay for the time they had engaged.

Of course they started to make objections, and the air was filled with
various excited exclamations; but Frank proved as firm as adamant, and
showed the automatic revolver sticking from his pocket all the while, a
fact that kept the two men from venturing to do more than shout.

Clutching their money they were pushed ashore by members of the crew,
who doubtless could give a pretty good guess as to what the whole thing
meant, since they had talked with Felipe.

"A good riddance of bad rubbish!" declared Andy, as the boat again
started up the river, leaving a pair of yelling natives behind, making
all sorts of furious gestures with both arms.

"Yes," pursued Frank, reflectively, "and if we wanted any more evidence
that we nipped a conspiracy to seize the vessel in the bud, there it is
in their anger at being paid for not working. Nothing like that was ever
known before down in this country, as Felipe says. And now, Andy, I
feel that we're another step nearer the carrying out of your great
task."

"Oh! I hope so," said the other, his face marked by an eagerness that
told of the one sole wish of his youthful heart.




CHAPTER XI.


OUT OF THE FRYING PAN INTO THE FIRE.

Frank took the first watch.

It was to begin about ten o'clock that night; for both of them had
remained on deck, talking, up to that hour. The night was so comfortable
after the hot day that they disliked going into the sleeping
quarters. These happened to face the deck, however, so that the vessel
was admirably suited to cruising in tropical regions.

"Every thing seems to be going on decently right now," remarked Andy,
yawning, as he prepared to have a few hours' sleep.

"That's so," returned his chum. "But while we've got some of the
faithful ones on duty, we mustn't forget that there may be other snakes
aboard. Enrique and the little shouter may not have been all the
sympathizers with the revolutionists. And not for a minute will we relax
our vigilance."

That was Frank's way; and just now Andy fully approved of it. His heart
was so set upon having a chance to use the monoplane in the endeavor to
discover that strange cliff-enclosed valley, where his father was
imprisoned, that he did not mean to take any chances of losing out
through over confidence.

So he packed off to his berth, while Frank prepared for three hours of
lonely vigil. He expected to make the rounds just about once in so
often, and have a few words with the man at the wheel. Felipe had
declared that it was his intention to keep busy himself through the
night, since he dared not trust the wheel in the hands of an
inexperienced pilot while darkness lasted.

In the morning he could give directions, and allow an assistant to do
the work, while he secured some rest.

There was no moon after early in the evening, when the young queen of
the night disappeared in the west, leaving the bright stars to control
the skies.

The boat continued to make good headway against the current, though at
this season of the year the Magdalena is bank full with the summer
rains, which fall almost every afternoon in a deluge.

A searchlight sent a dazzling shaft of light far ahead on the troubled
surface of the booming flood. This was an absolute necessity, for
otherwise it would have been too dangerous bucking against that tide;
laden as the river was with floating tree trunks of gigantic size, that
had been swept from their resting-places in the lowlands above.

Once Frank had seen a wild animal crouched on one of these great
logs. The boat passed so very close to the floating refuge of the beast
that ere darkness claimed the strange craft with its stranger cargo,
Frank had been able to see the tawny hide of the crouching beast, and
note the quick, jerky motion of its long tail.

Upon hurrying to the pilot house and making inquiries of Felipe he
learned that, just as he suspected, the animal was a jaguar, the most
feared inhabitant of the tropical forests away off at the headwaters of
the Magdalena and Orinoco rivers.

There was a spice of peril hovering over the progress of the little boat
during every hour of that night. It might come in the sudden leap of a
wild animal, that judged any port would be better than a floating
log. Then there was a chance of their running afoul of a monster
derelict, in the shape of a drifting snag, that might punch a hole in
their bow, and bring about trouble.

On top of all was this unseen peril from the revolutionists, who were
making the Magdalena country the center of their renewed activity, for
some reason or other, and had their minds set on securing the first
aeroplane ever known to be in Colombia.

The time passed away. When three hours had really gone, and all seemed
well, Frank awoke his chum. Generous to a fault, he might have held out
much longer, for he did not feel exhausted; but Andy, who knew him like
a book, had made him promise faithfully, on his word of honor, that he
would arouse him at exactly the time agreed upon.

"Everything lovely, and the goose hangs high!" Frank said, as the other
joined him presently on deck.

"That's good," replied Andy. "And as it is now one o'clock, with no
trouble doing, looks good to me that we'll pull through the night
without a mess."

"You never can tell," observed the careful Frank. "And the only way to
do is to act just as if you felt positive something was bound to crop
up."

"I know it," came the reply, as Andy started to walk up and down a bit,
so as to get the last remnant of drowsiness out of his system.

For an hour he found little trouble in keeping awake. He made frequent
trips to where Felipe stood at his wheel, his keen eyes keeping constant
vigil ahead, in order that he might steer clear of such snags as
threatened to stove a hole in the hull of the steam yacht.

Now and then Andy could see one of the crew moving about; but as some of
them must have duties to perform, even in the night, he did not look
upon this as a suspicious circumstance. Only, he made sure that no one
wandered in the near vicinity of the locked lazerette, where the
precious monoplane lay, securely crated.

In some places the river proved much narrower than in others. And, of
course, it was here they had their greatest trouble. The current was
increased, for one thing. Then the floating objects swept forward with
more speed, so that it required additional dexterity in order to avoid
them.

But old Felipe knew his business well. Andy believed they had made no
mistake in leaving matters fully in his hands.

It was about the end of his second hour that the pilot volunteered some
information that gave Andy more or less uneasiness.

"Just ahead, young señor," he said, when for the fifth time the boy
entered his deck pilot house, "we come to the narrowest place in the
whole river at this section. And there, if anywhere, I expect that they
will be waiting for us."

"Do you mean the revolutionists?" exclaimed Andy, interested instantly.

"No other, señor. If we manage to get past there, all will be well. But
they may be encamped on both shores, and demand that we draw in under
penalty of being fired on," Felipe went on, without removing his
snapping black eyes for even a single second from the ever-moving
panorama of shifting water and floating debris, that the searchlight
disclosed ahead of the laboring boat.

"But nothing must tempt us to obey; no matter if they send volleys
aboard. The distance is too far for them to do much damage; and I hear
they are as a rule pretty punk shooters."

Felipe may hardly have known what that word meant, but he could give a
guess.

"But sometimes, young señor, they even have cannon!" he remarked.

"You don't say!" ejaculated Andy, in new alarm; but he quickly caught
himself, and went on. "Let 'em try it then. We'll just shut off the
searchlight, and take our chances for a while with the old floaters on
the river. Then perhaps they won't see anything to bang away
at. Anyhow, just make up your mind, Felipe, we don't haul in, not while
the blessed old tub keeps above water."

"It is good to hear such brave talk," said the old pilot,
chuckling. "Me, I will keep going straight ahead, no matter what comes,
until I have the order from you to turn the boat. Yes, let them shoot,
señor. After all, I do not believe they could hit the side of a palace
in this dark."

All the same Andy thought he ought to arouse his cousin, and make Frank
aware of the new threatening peril.

On hearing the facts, Frank agreed with all the one on guard said, even
to being ready to extinguish the useful searchlight when the critical
moment arrived.

"We'll just have to take chances, that's all," he declared. "Even if we
came swat up against one of those floaters, that's no reason we'd be
snagged and sunk. They make these boats pretty strong, over there across
the big pond, and I guess our hull could stand a hard punch."

"Yes," remarked Andy, feeling easier, now that Frank was on deck, ready
to take matters in his able hands; "and after all, it's a choice between
two bad things, in which we pick out the lesser. Hang the old
insurrectoes, I say! Why can't they just pay attention to their own
business, and let us two peaceful Bird boys alone?"

"Well," laughed his chum, "you know how it is yourself, when you want
something pretty hard. And they've got the notion in their stubborn
heads that if they only had a modern, up-to-date aeroplane, they could
just make the miserly old government come to terms instanter. Don't
blame them too much, Andy. Maybe you and I would do the same thing--if
we were Colombians, and on the outs."

"Looks to me like there was something like a fire ahead, Frank!"
declared Andy, right at that juncture.

"I say, you're on the spot every time, old fellow," observed the other,
as he shaded his eyes to look. "There's a sharp turn ahead, where Felipe
says we enter the narrow place. And I honestly believe they've got a
bonfire burning on the right-hand bank."

"Then, after all, shutting off our bully little searchlight won't do us
much good," complained Andy, regretfully.

"Don't you believe it," Frank hastened to remark. "A fire isn't going to
reach all the way across the river, which is pretty wide, even at its
narrowest part. And depend on it, our clever old wheelsman will keep
just as snug up against the left hand shore as he dares go."

All the same, despite these assurances from his cheerful chum, Andy
confessed to a secret feeling of apprehension as they drew closer to the
point of land beyond which the danger possibly lay in wait.

It seemed to him that every conceivable species of peril threatened the
sacred enterprise, upon which he had so eagerly embarked. From various
sources did harm hover over their heads. And even though they passed
safely through all these, there must be many more to come, after they
had launched their little airship, and started to explore the strange
regions of this tropical land.

"It's a fire, all right, Frank," he said, as they negotiated the bend,
and opened up a new vista ahead.

"Yes, that's so for a fact," returned his chum. "And notice, will you,
Andy, how old Felipe has managed to keep over well toward the port
shore. He sized up the situation all right, and knew how to act."

"Yes, Felipe tells me he used to serve in the army. Many a battle he has
been through, not only in Colombia, but in other countries as well. He
was once something of a soldier of fortune. But where are you going,
Frank?" as his comrade started to leave him.

"I must warn the crew to keep out of sight, or they may be hit, if there
happens to be any shooting going on," called the other, over his
shoulder.

He found that every member of the crew seemed to be awake, as if they
had talked the situation over, and also guessed where the trouble would
lie in wait for the venturesome young Americano señors.

So Frank gave his warning, and saw that they obeyed. While they were in
his employ he felt a certain degree of interest in these ragged fellows,
and did not wish to be held responsible for any damage they might
receive, if inclined to be reckless at times.

When he once more reached Andy's side the latter was looking through a
pair of marine glasses they had fetched along, thinking they would prove
especially valuable in scrutinizing the country over which they might be
passing in the aeroplane.

"They're our friends, the revolutionists, I reckon," he announced. "I
can see several who carry big swords that dangle around their heels. And
the common soldiers, while they have little if any uniforms, and some of
them no shoes, seem to all have guns in their hands. Here, look and
tell me what that is on the little rise. I'm afraid our worst fears are
going to come true."

"Well, you're right, Andy," replied the other, after he had clapped the
binoculars to his eyes. "That's a cannon, all the same, and they're
getting ready to shoot!"

"Oh! my! It makes a fellow's flesh just creep, to think of being banged
away at with a great big cannon!" declared Andy.

"This one isn't so very big, I think. And now we're nearly opposite
where the fire burns. They're going to make a move to show their
hand. Drop down flat on the deck, Andy--quick with you!" and Frank, as
he spoke, set the example himself.

Hardly had the two boys thus thrown themselves down than there was a
heavy boom, accompanied by a brilliant flash of fire from the shore.

The revolutionists had fired upon the little steam yacht!




CHAPTER XII.


A GREAT SURPRISE.

"Wow! now, what do you think of that?" exclaimed Andy, raising his
head, just as one of the big turtles native to these warm waters might
thrust his out of his shell.

"Why, that was only a warning to bring us up short, and pay attention!"
declared Frank. "Because, as you saw, the ball splashed the water ahead
of our bow."

"But Frank, we don't mean to head across?" cried Andy, getting up on his
knees, the better to see.

"To be sure we don't. That was all settled long ago; and you notice that
our good Felipe is still keeping her nose headed straight upstream. Now
out goes the searchlight, just as we arranged. Wonder what they'll think
that means!"

"Perhaps they'll believe they knocked it overboard with that shot!"
suggested Andy, who could joke, even when facing troubles as thick as a
sea fog.

"Listen!" Frank exclaimed, "there's a chap with a pair of leather lungs,
shouting a lot of gibberish. I suppose he's demanding our surrender, and
threatening to blow us to smithereens if we decline to believe him."

"One good thing is that each minute takes us further up the river, and
every foot counts in this game of runaway. Already we're past where the
gun stands; and those fellows are working like fun to get her turned
around, so as to point after us. While they load we're doing more
stunts. Yes, and Frank, we're leaving 'em in the lurch, I do believe."

"Sure thing," returned Frank, composedly, "only both of us want to duck
when it looks time for the blamed old gun to bang again. They mean
business from the word go, now, and will shoot to hit! By some accident
it might run afoul of the boat, and splinters fly. There, get ready to
drop, Andy! It's coming!"

It certainly was, for immediately another flash sprang up, accompanied
by the same deep bellow, as the fieldpiece was discharged. No doubt,
while it may have been rather out of date in pattern, the cannon was
good enough to have done savage execution, handled by expert German or
French gunners.

But there did not seem to be any such among the rag-and-bobtail army of
the new aspirant for the presidency of Colombia. At any rate, the
missile whizzed and whined past the retreating boat, missing her by
yards.

"Bully!" shouted Andy, jumping up and cutting a few pigeon wings on the
deck to illustrate just how pleased he was. "By the time they're ready
to let her off again we'll be nearly out of range. And from the looks of
the bank I feel pretty sure they never can catch up with us, toting
their old gun along."

Three minutes later there came the third report, and they heard the ball
pass high overhead, proving that the marksmen had entirely lost all
traces of the boat and simply fired at random.

"That settles it," said Frank, decisively.

"Do you think so?" asked his chum, joyously.

"No question about it, Andy. Like the government official on the wharf
at Barranquila, they realize that the game didn't work, and if they want
to get us they'll have to lay some new plans when we come back
again. But we're not bothering our heads about that, you know."

"Never even cut a chip off our boat!" declared Andy.

"Well, I'm going back and get the rest of my nap. Wake me up at four,
remember. I want the last watch," and Frank dove within his stateroom
with as much seeming indifference as though this thing of being fired
upon with fieldpieces might be an everyday occurrence in his experience.

Morning dawned upon the Magdalena. Frank was on duty at the time and
drank in the lovely picture. Birds flew overhead, cranes arose from
along the shallows in near the shore, where they had been fishing for
their breakfast, and there were many strange feathered creatures to be
seen, such as the boy had never up to now set eyes upon.

Some of the crew were trailing fish lines astern and every now and then
a prize would be hauled aboard, which later on might afford a meal for
passengers and workers.

Andy soon made his appearance, the rising sun having sent a few slant
rays into his sleeping quarters and aroused him by falling on his face.

"This is something like, eh, Frank?" he remarked, as he drew in a big
breath of the bracing morning air.

"I should remark, yes," was the other's reply.

"We've apparently left all our dangers behind," Andy ventured. "That is,
I mean there's little likelihood of our being robbed of our precious
machine now, with both government officials and envious revolutionists
left in the lurch."

"I was just asking Felipe and he says we shall have another day and
night of bucking up against this nasty current. You see, Andy, it's on
an unusually big bender right now, which makes it doubly hard to fight
it."

"Oh, well, what can't be cured must be endured, I guess. So I'll try to
take it as easy as I may and be thankful it's no worse," Andy replied.

The morning passed without any event worth mentioning. And all the while
they kept steadily at the business of eating up some of the two hundred
miles that Felipe assured them lay between Magangue and the city at the
mouth of the big river.

Another thing was worrying Andy, however. He finally broached the
subject to his comrade knowing that in this way he would get relief.

"That blessed old engine has been doing bully for a long time now,
Frank, but judging from past experiences, she's due for another sulky
fit soon. Whatever would we do if she let down all of a sudden, while we
were right in the worst kind of a swift current? My! we'd be carried
miles downstream before we could do anything."

"Oh, no we wouldn't!" remarked the other, smiling.

"Then you've been thinking it all over and made ready to offset a balk,
I bet anything," declared Andy, with vehemence.

"Do you see that anchor forward?" asked Frank, pointing from where they
stood on the raised deck aft. "Well, that's got a good long stout chain
attached and is placed where a kick will send it over. Notice old Quita
squatting close by? Think he's taking a snooze, he seems so quiet? But
all the time the old chap's on the alert, and he has his orders, too."

"To upset the anchor over the bow, you mean?" asked Andy.

"Just that," came Frank's reply. "If anything happens to the machinery
you'll hear a series of quick whistles from Felipe. The boat won't even
have a chance to lose headway before over plumps the big mudhook, and
we'll just take a rest out in the river until repairs can be made again
by Engineer McClintock and his assistants."

Andy looked at his chum admiringly.

"Blessed if you don't just think of everything!" he said; "and get
ready long before it happens. However do you do it, Frank?"

"Oh, it's easy, once you make up your mind," laughed the other. "I took
to it long before this new Boy Scout movement started. You know they've
got as their leading motto the words: 'Be prepared.' And there never was
a better slogan ever given to boys. Think how many things might be
avoided if we were always prepared."

"Yes, I've given the subject much thought," grumbled Andy; "but somehow
I seem to slip up when it comes to the critical time. I stay awake
eleven hours, and just when I doze off in the twelfth watch the blamed
thing happens! It's always that way, seems to me. How can a fellow stay
awake all the time, tell me that?"

"Oh, rats! There's no need of that. Just fix things so you'll be aroused
when it comes along, and be ready to turn the tables."

So they talked away into the afternoon. The engine seemed to be on its
best behavior. McClintock, the Scotch engineer, who was the only
foreigner aboard besides the boys, reported that he was beginning to
have more faith in the machinery. The work of the last twenty odd hours
had certainly been a pretty heavy tax on it and everything seemed to be
going like clockwork.

"I only hope it'll keep up, then," said Andy. "One more night is all I
ask. Then Felipe promises to have us at our journey's end, when I can
see and talk to the very man who picked up that wonderful little
parachute, with its message from the unknown valley among the cliffs. I
wish the time was here right now."

"Felipe, by the way, is taking his rest now," said Frank, after a little
time; "for he expects another night on duty. We still meet many tree
trunks sweeping down on the current. The man at the wheel has to keep on
guard constantly. Look at that tremendous one, will you, Andy? And just
notice how dense the forest is ashore around here. How any one can get
around at all beats me. I should think they'd have to keep their
machetes busy all the time cutting the matted vines away."

"I understand they do," the other went on. "And I rather guess that
there's hardly a country under the sun where an aeroplane would be of
more real benefit than right here in the tropics. Think of avoiding all
that tangle--of floating along, a mile a minute if you wanted, far above
the tree tops and away from all such a muss."

"You're right," agreed Frank, fervently. "And it's the only way any one
could ever hope to discover this strange prison of your father. From a
distance of a thousand feet we can have a big range of vision. With our
good glass it will not be hard to discover the cliffs, if only we figure
out in which direction we can have the best chance. And I think I've got
a scheme ready to manage that."

"I depend on you to do it," said Andy. "Alone by myself I would simply
despair of ever learning anything worth while. But while you are along I
just feel that we're going to succeed."

"I ought to thank you for saying that, but I won't," Frank
declared. "Because it makes me tremble for my reputation as a prophet."

"But you have seen nothing to make you less confident, I hope?" cried
the other.

"To be sure I haven't," replied Frank, readily enough. "On the other
hand, I ought to feel better satisfied than ever, because we've managed
to outwit every cause for trouble that has cropped up this far. We'll
get through this coming night without accident, because we're ready for
anything. Then, when another day dawns, we'll haul in at Magangua, to
hunt José Mendoza up and hear what he can tell us about the parachute
that fell among his cocoa trees."

"Hark! what ails the men forward?" exclaimed Andy just then.

They sprang to their feet and rushed to where they could see what was
going on.

"Perhaps a mutiny!" exclaimed Frank, who could not tell what queer thing
was ever going to happen down in this land, the people of which were so
different from all whom he had ever known before.

Andy uttered a low cry of alarm and began to fumble for the revolver
Colonel Josiah had made him promise to always carry on his person, once
they reached the country of revolutions.

The first sight they obtained told them that something unusual had
indeed happened. A number of the native crew were in range of their
vision, but every man had fallen flat on his face and seemed to be
cowering there as if afraid.

"What in the dickens is it?" gasped Andy.

"I don't know. They are a scared lot, that's sure! Perhaps they saw a
sea serpent alongside! It couldn't be that a jaguar has boarded us. No,
look at old Quito, how he lifts his head and takes a terrified look!
Why, he seems to be observing something up above in the heavens as sure
as you live!"

As Frank shot out these words he, too, bent his head back to scan the
brazen sky above. A cry broke from his lips.

"Why, what under the sun does it mean?" exclaimed Andy, who had also
turned his eyes heavenward to discover a strange thing speeding over the
tops of the trees, one, two thousand feet high, and at the same time
there came to his ears a familiar throbbing that could have but one
meaning.

"An aeroplane!" he burst forth in thrilling tones; "and the sillies down
there think it's just a frightfully big bird about to carry them
off. Hey, Frank, perhaps the government has got one of the new
contraptions after all!"

"Go slow," said Frank. "Suppose you look a bit closer, my boy. Isn't
there something familiar about that same craft up yonder?"

"It's--it's a biplane, Frank!" gurgled Andy.

"Yes, and one you've set eyes on before, too, old fellow. It belongs
to--"

"Puss Carberry!" burst from Andy's quivering lips, as he continued to
stare, as if almost unable to believe his own eyes.




CHAPTER XIII.


THE "DEVIL-BIRD."

"Yes, Puss Carberry and his crony, Sandy Hollingshead!" declared Frank,
positively.

"But, it seems impossible! All these hundreds and hundreds of miles away
from old Bloomsbury and Puss Carberry floating over us! Sure I must be
dreaming, Frank!" stammered the other, still gaping up at the rapidly
passing aircraft.

"No, you're just as wideawake as ever you were in all your sweet life,"
said Frank. "Take a better look, Andy; don't you see now that it's the
same biplane we raced with the day Sandy dropped that bag of sand,
hoping to break our winning streak in the dash for Old Thunder Top?"

"Anyhow it's a ringer for it, I give you my word!" muttered the stunned
boy.

Frank, with an exclamation of impatience, sprang forward and snatched
something up that had just caught his attention. This proved to be the
fine field glasses that had been brought along on the adventure.

These he clapped to his eye, and as they were already fitted and adapted
to his sight, he lost not a second in covering the passing aeroplane.

"Look for yourself, my boy!" he cried, handing the binoculars over to
Andy, who hastily raised them.

"Well, I declare, that settles it!" ejaculated that individual
immediately.

"You recognize them, then?" asked Frank.

"It's Puss as sure as thunder. I can see him plain. The other is just
out of line, but there's something about his figure that makes me ready
to say it's our old friend, Sandy," Andy replied, amazement still
gripping him tightly.

"Well," Frank observed, "after all, the only queer thing about it is our
glimpsing them so soon. We knew they were headed down this way
somewhere, but they made quicker time than our best. And just to think
that they're the first to fly an aeroplane along the region of the
Magdalena."

"Huh! they beat us up in the air that other time, yet when it came to a
showdown, we left 'em at the stake!"

Andy was beginning to recover his breath, and with it came renewed
confidence.

"Do you see anything in the actions of Puss that would indicate he had
recognized us aboard this boat?" asked Frank, for the other still kept
the glasses glued to his eyes.

"No, I don't," replied Andy, presently. "You see they're awful high
right now, and without glasses they could never make us out down here."

"I guess you're right," was Frank's decision. "Perhaps it's just as
well, for there's never any telling what mean trick those fellows have
got up their sleeve."

Andy suddenly removed the glasses and a sudden pallor seemed to cross
his face.

"Oh, Frank!" he cried, "you don't believe they'd ever be so wicked as to
try and stop us from searching for my father, do you? Bad as Puss
Carberry is, I can't just believe he'd ever do that."

"Well, I hope not," returned the other, but there was a trifling vein of
doubt in his voice, for he had long ago ceased trying to figure to what
depth of depravity those two schemers might descend.

"But where do you suppose they came from right now, Frank?"

"That would be hard to tell," Frank replied. "The first you saw of them
they were sailing up over yonder. Then the chances are they have
quartered themselves at some town, perhaps on the river, and that this
is just their first flight--a sort of look over the country."

"Yes," said Andy, "they're circling right now as though they mean to
head back again."

"Well, you can't blame them much," Frank ventured, watching the actions
of the aviators above with keenest interest. "Night isn't so very far
away, and I should think a fellow would hardly feel like being caught
out after dark down here in an airship."

"Well, hardly," Andy smiled. "Curfew must ring for us every time. Fancy
dropping plump in the middle of such a jumble of forest as that is
yonder, and I bet you it's just cram full of snakes, jaguars and
everything else that would want to snuggle up to a poor birdboy dropped
out of the clouds. Me for daylight when I go sailing down in this
blessed region."

"Look, the men are beginning to recover from their fright," remarked
Frank in low tones. "There's old Quito sitting up now and commencing his
everlasting jabbering with the others. See him point to the biplane and
then to us, Andy."

"Say, the sharp old coon is getting a pointer on us. He's telling his
chums right now that the thing we've got stored away in the lazerette is
just such a big bird as that going away over yonder. Am I right, Frank?"

"You never said a truer thing. But they were certainly a badly rattled
crowd for a time. And we can hardly blame the poor fellows, for what
could they think but that it was a tremendous bird of prey, looking them
over with an eye to grub?"

Frank laughed a little as though the recollection of the fright of the
crew would always seem more or less ludicrous.

They sat there and watched until the mysterious biplane had completely
disappeared in the hazy distance that marked the coming of evening.

"You don't think then," asked Andy, when it had vanished from view,
"that Puss and his biplane could have fallen into the hands of the
Colombia authorities and that they're using it for scouting to learn the
movements of these ragged revolutionists?"

"No, I don't," was Frank's quick response. "You said you could
positively make out Puss at the wheel, and I'm almost sure it was Sandy
with him. They must have slipped into the country without giving their
secret away. Trust sly Puss for knowing how to do that sort of
thing. He never goes around with a brass band, telling what big things
he has on tap."

"That's right. Why, just think, not a soul knew about his old biplane
until he had it about done. We were working in the open almost, telling
much of our plans, but Puss pretended to be mighty envious and asked
questions, when all the time he was meaning to beat us out. Of course,
he could get into Colombia without giving his secret away. You don't
need to tell me, Frank, you're surprised at that."

"No more I am. But there goes the sun. How quick it seems to drop out
of sight down here," Frank remarked.

"Sure," laughed his cousin, "but all the same I fail to hear any
bang. You remember the Irish immigrant who heard the sunset gun at a
military post in America for the first time and on being told that it
denoted sunset, innocently exclaimed, 'Sure, the sun niver goes down in
Ould Ireland wid a bang like thot!" But already the dusk is creeping
out of the dense woods on to the river. And I'm getting hungry. It must
be near supper time. I wonder what the folks up home are doing right
now?"

"Just what we are, likely--waiting to hear a welcome sound that will
call them in to feed. And there comes little Pepito to blow the conch
shell that he uses for a dinner bell. Come, Andy, get a move on
you. Another night and then we are going to do business at the old
stand. It will be just fine to soar above this strange country and see
for miles and miles--mountains, valleys, rivers, tropical forests, and
everything that we've never looked down on before."

The two young aviators went into the cabin for supper. They fared very
well insofar as food was concerned. Of course, both of them missed the
home cookery. The native who attended to this part of the program did
his level best to please, and he certainly had plenty to work with. But
his Spanish style of serving even the most ordinary dishes of tinned
meats with a dash of garlic was beginning to pall upon the taste of the
American lads.

Frank had even started to show him other ways of cooking, and they had
hopes of converting the cook by slow degrees.

The night was in one sense a repetition of the preceding one. True, they
would not have to consider being halted by a gathering army of the
revolutionists, and that was a comfort all around. At the same time
Frank deemed it necessary that he and his cousin keep watch. And Andy
was perfectly willing to sacrifice some of his personal comfort for the
sake of insuring the safety of the precious aeroplane.

It proved just as well that they had so determined. During Frank's
second term on guard and somewhere around four o'clock, while darkness
covered the land, he thought he caught a glimpse of a shadow crossing
the deck, headed in the direction of the lazerette.

He had been lazily reclining on a soft cushion made of several blankets
and looking up at the silvery stars, but immediately he became fully
aroused. This might mean danger in some shape toward the aeroplane. And
no matter, it behooved him to investigate.

So he softly arose to his knees and crept after the shadowy figure.

Cautiously he approached the place where the door belonging to the
storeroom was to be found. As he advanced thus he could occasionally
catch a peculiar clicking sound, which he believed must be made by some
one trying to pick the lock!

The engine of the boat kept up considerable of a racket as it steadily
worked along without the dreaded hitch. Besides, there was always more
or less splashing of water against the sides, as they pushed against the
swift current of the Magdalena. All these things combined to muffle the
clicking sound frequently, yet during little lulls Frank could catch it
again.

The tumult also served to deaden any shuffling he may have made while
creeping toward the lazerette door, and for this Frank was thankful.

It was very gloomy here. A hanging lantern some distance away only
served to accentuate the gloom apparently. Still, by straining his eyes,
Frank believed he could just manage to make out a stooping figure at the
door. Yes, he was certain that it had just moved, and now the peculiar
clicking was much plainer.

When it stopped he remained perfectly motionless, nor did he again
commence his creeping forward progress until it started once more.

Frank no longer had the slightest doubt concerning the cause of that
suspicious clicking. One of the crew was endeavoring to force an
entrance into the locked lazerette, doubtless with the intention of
destroying the valuable aeroplane. He might be in league with the
revolutionists and in this way hoped to prevent the government from
eventually securing possession of the machine which would put the
insurrectos out of the running.

But Frank had conceived another idea. He now believed that his fellow
might have been sent by the crew to destroy the "devil-bird," as they
undoubtedly considered a contraption that could soar through space as
fast as the fleetest condor.

No matter. It was his business to put a sudden stop to the action. And
while doing so he must not be too rough in his dealing with the fellow,
lest the entire crew rise in revolt.

When he had reached a point that allowed of a leap, Frank suddenly
sprang forward. He did not know just what he might be up against and had
even taken from his pocket the splendid new pistol which Colonel Josiah,
himself a world traveler, had insisted upon giving each of his boys
before they started on their trip south.

"Surrender!" cried Frank, believing that the very sound of his voice
would do much toward frightening the would-be traitor.

But he hardly expected such a tremendous upheaval as followed. The man,
believing that possibly the "devil-bird" had broken out of its cage and
was about to carry him off in its gigantic beak, gave a shrill scream of
terror, and bouncing up, broke the slender hold Frank had secured upon
his person.

Not to be outdone, Frank, recovering, chased after him. He believed it
his duty to at least learn the identity of the rogue, so that he might
understand just how deeply the conspiracy had taken root in the crew.

Between himself and the hanging lantern he could make out the fleeing
figure of the fellow, and hot in pursuit he followed as fast as his feet
would let him. The man undoubtedly heard him coming, for, if anything,
his fright increased. Out upon the open deck they flew, Frank just a few
feet in the rear. He had even stretched out his arm and touched the
garments of the runner, when with a screech the fellow made a furious
plunge straight over the side of the boat.

He evidently chose to take chances in the swift current of the Magdalena
rather than trust himself in the power of the unknown pursuer, which
doubtless he believed to be the dreaded "devil-bird" that had been
confined in the box cage!




CHAPTER XIV.


THE AIRSHIP LAUNCHED AT LAST.

Frank came near following after the unknown member of the crew, when the
other made that flying leap over the side of the boat. Not that he
wanted to take a bath just then, but his forward progress had been
rapid, and he only saved himself by banging up against the taffrail,
which was unusually high for so small a vessel, and holding on sturdily.

He had heard the splash as the fellow reached the water. Doubtless he
was a good swimmer, as about all these natives seemed to be, and barring
his falling a prey to some loitering alligator or other reptile, he
would be able to gain the neighboring shore further down.

At any rate it was folly to think of looking for him.

"What's all the row?" cried Andy, as he came plunging forth from his
stateroom.

Some of the crew were even then looking over the side, and Frank
imagined they could give a pretty good guess as to what it meant. But
he heard not a word from even old Quito, and while the absence of a man
must be noticed in the morning, there would probably be no complaint.

When Andy heard about the attempt to injure the monoplane he was in a
tremble.

"Did you ever?" he exclaimed. "Why, it seems as though everything just
wants to knock us. When we give the government officials the merry ha!
ha! and even slip past the revolutionary army, after being bombarded by
their old cannon, here even our own men want to smash our precious
aeroplane, under the belief that it's an evil bird, come to bring bad
luck to the people."

"Better go back to your bunk and forget it," remarked Frank, who was
tenderly rubbing his elbow where it had come in contact with the hard
taffrail at the time he stopped so suddenly, balking at a bath.

"Me? Not on your life, Frank!" declared Andy, with much emphasis. "I'm
going to take a blanket and just lie down in front of that blessed
door. Nobody can get in then without walking over my body. And if I
catch a fellow trying it on, believe me, I'll give him something he
won't forget in a hurry. It'll be touch and go with him, I bet you."

Which he actually did, much to Frank's secret amusement, camping out
there on the floor as close to the locked door as he could get, and
bracing his back up against the same.

But then, fortunately, morning was not so far away and Andy would have
only a couple of hours, more or less, of his self-imposed labor.

They knew that if the pilot of the river expedition said truly, they
must even now be drawing near the town of Magangue. Possibly it would
break upon their vision with the coming of dawn.

Frank himself had no more intention of retiring to his bed than had
Andy, but continued to keep watch and ward until he saw the first peep
of daylight over the port side of the vessel.

Then he communicated the glad intelligence to his chum, and together
they stood there, watching the slow unfolding of dawn. From an ashen
gray the sky began to be marked with brighter hues; pink flushes
traveled along in lines that centered in the spot where the sun would
presently appear, and the gloom of night retreated once more back to its
hiding places among the mountain passes.

"There's the dinky old town!" cried Andy, pointing with trembling
finger.

"It is and no mistake," replied Frank, himself experiencing a sensation
of considerable relief, for at times it had seemed more than doubtful
whether the little expedition could ever overcome the many difficulties
that beset its passage up the swollen river.

And so they came to land just as the glorious sun showed his smiling
face. Andy declared that this was a harbinger of good luck, and his
cousin chose to readily agree with all he said, for it pleased him to
see Andy look more like his old self than he had been for many a day.

"Remember, only one of us ashore at a time until we land this cargo,"
remarked Frank, as they came to bring the boat to the bank, where a
group of natives waited to see what it all meant, surprise written
largely on their dark faces.

"That's right," responded the other traveler. "But I'm going to have
the aeroplane carried out on deck at once, so it can be taken ashore as
soon as we find where we are at. What we want first of all is to hear
about our friend, Carlos Mendoza, the cocoa planter. Perhaps he lives
miles away and we'll have to get some sort of conveyance to tote our
machine out to his place."

"Yes," observed Frank, "I've been laying out plans along that line. If
you don't mind I'll drop ashore while you're having the crates brought
on deck and make inquiries. Even away down here in this wilderness money
talks. Colonel Josiah told us it did for him in the heart of darkest
Africa, you know. And a few bolivars will hire all the help we want."

Andy was perfectly agreeable that his companion should have taken upon
himself the task of engineering things.

"You can always discount me when it comes to bargaining," he said,
laughingly; "so go ahead and fix things to suit yourself, Frank."

Upon reaching shore, Frank, who had taken old Felipe along with him to
serve as interpreter, found that Carlos Mendoza had his home just on the
border of the town, though it was a little distance away. He soon made
arrangements for hiring a native cart to be used in transporting the
precious aeroplane.

In less than half an hour they were on the way. The boat had been left
in charge of McClintock, the Scotch engineer, who would make sure that
the crew remained on board or lost the wages coming to them.

Both of the boys were so excited that they paid little attention to the
strange scenes which now surrounded them in the valley town far back in
the interior of tropical Colombia. Indeed, one might even have suspected
that they had always been accustomed to living in a region where all
manner of tropical fruits abounded, coffee and cocoa were raised as
crops, and birds of brilliant plumage flew overhead.

The truth of the matter was, they knew they would presently come face to
face with the planter who had actually picked up the little messenger
sent out of his cliff bordered prison by Professor Bird. And this fact
set their nerves to trembling with eager anticipations.

In due time the cart on which the aeroplane had been secured, together
with the luggage which the young aviators wished to carry along, drew up
before a long, low white building, back of which could be seen orange
trees and other evidences of a real tropical home.

Their coming must have been noted, for a gentleman was advancing from
the grove at the rear. Señor Carlos looked surprised at seeing the
caravan bringing up before his door, but that was as nothing in
comparison with his amazement upon learning how one of the two young
Americanos was the same Andrew Bird to whom he had desired his friend,
Señor Almirez, to forward the strange message picked up in his cocoa
grove one day several months back.

The boys had learned from Señor José that the owner of the plantation
could understand English and even speak it fairly well. Thus they had no
need of fetching Felipe along to act as interpreter.

"Oh, please first of all let me see the remains of the silk parachute
that was attached to the bark letter!" said Andy, after they had
conversed for a short time and some of the planter's hired servants had
unloaded the boxed aeroplane, which was stowed away in a place of
security.

Doubtless the planter understood the reason for the boy's solicitude. He
immediately took them inside the house and in another minute had thrust
into Andy's eager hands a discolored piece of silk, such as is used in
the making of balloons.

Nor did either Frank or the Colombian planter think it strange that the
boy should press the token again and again to his lips, while tears ran
down his face. They could understand the feelings that filled his heart,
and no matter what the nationality may be, the honest love of a lad for
his father cannot but provoke admiration and respect.

"And now," said Frank, presently, when his cousin had in a measure
recovered from his first emotion, "will you tell us, Señor Mendoza, just
how you found this strange communication? I hope you remember the exact
day, because it is of the greatest importance to us that we learn, as
near as possible, from just what quarter it came."

"Si, señor, I understand that," replied the planter, eagerly, his dark
face aglow with enthusiasm. "I made note of the day in my diary, also
the fact that it was the third day in succession when the wind blew
direct from the south, with just a faint turn to the west."

"Splendid!" cried Frank, turning to give his chum a reassuring
nod. "What did I tell you, Andy? The forethought of Señor Carlos has
made our task much easier. There can be little doubt, then, that the hot
air balloon must have started in a region that lies almost due south of
here, possibly with a slant, as he says, toward the south by west
quarter, as a sailor would call it. And now, señor, can you tell us just
where a direct line that way would bring us?"

"First over the lowland and the forests. Then, if you go far enough
amigos, it is the Sierra San Jeronimo mountains you would strike,"
replied the planter.

"Yes, I remember them on the map we have, and that corresponds exactly
with all I had in my mind," Frank observed, his forehead wrinkled with
serious thought.

"What sort of country is it up in those mountains?" asked Andy.

The planter shrugged his shoulders.

"That I am unable to tell you, amigos, since I have never been
there. From all I have heard I believe it is one of the wildest and most
inaccessible regions in all our country. Lofty peaks warn back the most
daring explorer. Few have ever ventured to attempt to go among
them. Some never came back, they say. The superstitious declare those
mountains are filled with evil things. Nothing on earth could tempt one
of my peons to accompany an expedition thither."

"Then it is lucky that we will not need any assistance in our
adventure," remarked Frank. "With an aeroplane one may be independent
of help. And now, Andy, what shall we do? It will take us the better
part of the day to assemble our little flier and get things ready for an
ascent."

"That means another horrible night of waiting before we can make a
start," said Andy, looking quite forlorn.

But he soon understood that it could not be helped. Both boys were
presently hard at work, with the deeply interested planter watching
every move. All the while they conversed and the subject of pretty much
all their talk had more or less to do with the country, the
peculiarities of climate, what sort of weather they might expect to have
and dozens of similar matters.

Doubtless Señor Mendoza would like to hear of things connected with the
great outside world, which he seldom saw anything of, but he realized
that these would keep until after the brave young señors had completed
their task of humanity.

Before evening came they had everything arranged to suit the critical
Frank. Both boys were pleased to find that the monoplane had come
through its long journey without any damage having been done.

That night they were uneasy about the precious airship, and at their
request the planter had their beds made up in the shed where the "Bug"
lay. But there was no attempt made to injure it in the least.

Then came the morning. Andy could hardly eat a bite of breakfast, for
the eagerness that possessed his soul. Every servant on the plantation
had gathered to look with awe upon the wonderful bird-like machine, on
which, it was whispered, these two venturesome young Americanos meant to
soar among the clouds.

Finally the last word was spoken, the planter shook hands with each of
his visitors, Frank turned on the power, the aeroplane with the motor
exhaust sounding like a volley of musketry started to run along the
level ground, and presently, to the consternation of the entire
gathering, began to climb upward, just like a creature of magic!

Cries of awe arose from scores of throats and to a man the peons threw
themselves flat on their faces, hardly daring to look at the terrifying
spectacle.




CHAPTER XV.


AN UNPLEASANT SURPRISE.

"At last, Frank, we're on the move!"

"Yes," replied the one at the wheel, as the cries and cheers from below
were drowned by the volleying motor explosions; "and did you see the
señor kissing his hand after us, while his men were flat on their
faces?"

"It was a queer sight," Andy remarked. "And no wonder these ignorant
peons call our little monoplane a 'devil-bird.'"

"Look down now. Just to think of two Yankee boys being allowed to swing
over a tropical scene like that," said Frank.

Both of them were deeply interested. In the valley they could see the
little town, with the river stretching off toward the south. Then there
were the patches of tropical vegetation, the fruit trees and the cocoa
plantations--all those interesting things which neither of them had ever
set eyes on before.

Señor Mendoza had told them how the coffee was grown upon a certain part
of the mountain slopes, since it did not do well in the valleys,
preferring a higher altitude.

They followed the course of the river generally, intending to cover
possibly something like eighty or ninety miles before trying to comb the
land from side to side, in the endeavor to find the strange cliff
enclosed valley.

From time to time Andy would call the attention of his aeroplane chum to
some striking feature of the landscape far below. The little Kinkaid
motor was humming merrily, without ever missing a stroke, and Frank,
having the utmost confidence in its steadiness now, after so many trial
spins, could take a few seconds at a time to observe these things.

"When we've gone something close on an hundred miles direct," remarked
the pilot of the craft, presently, "I think we'd better make a descent,
if given the chance."

"You spoke of that before," remarked his companion, anxiously. "What is
the reason for doing it, Frank?"

"Oh, nothing serious," replied the other. "We will then be at the
parting of the ways, you know."

"You mean we'll be about to leave the river that will have been our
guide up to then?" asked Andy.

"Yes," Frank admitted. "And from that time forward we must simply depend
on our judgment for everything. In that event it might be well if we
looked over the entire plant, to make sure everything was in apple-pie
shape."

Andy breathed freer.

"Oh, I agree with you there," he hastened to say; "and I'm glad you
hadn't any more serious reason. But did you ever see such a picture in
all your born days? Just look at the forest bordering the river. Think
of trying to push through such a dense mass of over-grown jungle. And I
bet it's just full of snakes, poisonous spiders, lizards and all such
things."

"Not to mention such trifling citizens as jaguars, ocelots, tapirs,
alligators, crocodiles and their kind," laughed Frank.

"Ugh! what lucky fellows we are to be away up here, where we can skim
along at the rate of thirty miles an hour easily, without half trying,
and snap our fingers at all those things. I tell you, Frank, this
aviation business is the greatest thing that ever came down the pike."

So they continued from time to time to converse as they kept pushing
along, following the winding course of the swollen river that could be
plainly seen below, between its banks of forest.

Frank did not soar high at this time. There seemed no need, and besides,
both of the boys were deeply interested in watching the various changes
that kept taking place in the checkerboard landscape below.

Several times during the first hour they passed over hamlets or
villages. On such occasions it was ludicrous to observe the excitement
that occurred. The Bird boys would not have been true to their nature
had they not enjoyed the tremendous sensation which the sudden and
unheralded appearance of the aeroplane caused in these river
settlements.

Loud shouts floated up to them that constantly grew in volume. Men
yelled, women and children screamed. Many fell flat on their faces;
others tried to conceal themselves, as though they belonged to a covey
of wild ducks over which a hungry eagle hovered, picking out his
contemplated dinner.

And the last thing Andy would see, as he looked back, would be wildly
running figures gesticulating furiously and evidently next door to crazy
with excitement. Apparently these natives believed that the aeroplane
must be a visitor from another world, or else some monster bird of a
family long understood to be extinct.

The second hour had nearly ended and everything seemed to be moving
along smoothly. Frank saw not a cloud on the horizon thus far. Surely
this augured well for the ultimate success of their strange expedition.

Suddenly he heard Andy give vent to a cry of alarm.

"What is it?" he demanded, quickly.

"Turn her upward, quick! They are going to shoot at us!" shouted the
other.

Frank instantly started to obey, and while their forward progress still
continued unabated, the aeroplane commenced to head toward a higher
altitude.

Immediately he heard the dull report of a gun from below. He dared not
bend his head to look, since all his attention was needed to take care
of his machine at such a critical moment. But the whine of the bullet
as it passed close by was very plainly heard.

Then came other shots, many of them, and the air seemed full of strange
hissing sounds. Twice Frank felt a slight shock that told him some part
of the aeroplane had been struck by one of the flying missiles. His
heart seemed to jump almost into his mouth, as he trembled for the
result. But nothing happened. The motor kept up its insistent humming,
and there was not a quiver to indicate that a vital part of the
monoplane had been injured.

"Andy, are you hurt?" he called, after the volley had ceased, the
marksmen below having evidently exhausted their ammunition.

"Only a scratch," came the reply. "Hardly drew blood. Think a splinter
from the wood where a spent bullet zipped past must have hit me. It's
all right, Frank! We ran the gantlet just fine. But all the same I guess
it would be better for us to keep a little higher after this."

"Did you make them out and were they government troops, do you think?"
Frank asked, for though he managed to turn his head, already had they
made such speed that only the interminable forest could be seen in their
rear.

"No," returned his comrade. "I just reckon it was another camp of these
insurrectos. You remember the señor said there were apt to be more than
one crowd of them up the river. It's the only way to get in and out of
this country, and everything that happens has to count on a water
route. I guess the Magdalena is about the same to this part of Colombia
that the old Nile is to all Egypt."

"Well, it was a narrow escape, all right," Frank declared. "I don't just
like the sound of those bullets all around when you're six or eight
hundred feet up in the air."

Andy had recovered from his recent fright by now and could even laugh.

"I should say nix," he observed; "especially when you know that one
little clip on either wing would upset us like a stone. Excuse me, if
you please. I'll never be fully happy when flying until we invent some
sort of little parachute that in case of a drop will give a fellow a
chance for his money."

Another hour passed, when Frank declared they had now reached the point
where a descent would be advisable in case they found an opening that
looked suitable.

"There are the mountains over yonder on the right," he said, "and from
now on we had better begin to scour the country, covering every mile
just as though we had a comb and meant to explore it all."

The chance to drop came presently, and as the opening proved everything
they could desire, a landing was made without the least trouble. Here
they rested and partook of a light lunch, having brought plenty of
provisions along, together with a gun of the latest repeating type, with
which Colonel Josiah had presented them.

Frank, upon looking the aeroplane over a little later, discovered that
he had been wise in deciding to make a halt. There was need of some
attention. Certain parts had become weakened by the strain, either in
the long voyage and handling on board the steamer, or else in this new
flight.

He was determined to be thorough in all he did, and this consumed more
or less time, so that when he finally pronounced the monoplane in
perfect condition the afternoon was half gone.

Still, they must go up and put in an hour or two searching. Andy was too
wild with impatience to hear of anything else, and Frank saw no reason
for not complying.

"But we must be sure to get down again before night comes," he remarked,
after they had made a successful rise and were speeding above the top of
the thick forest. "If we should be caught out at night I rather guess it
would be a serious piece of business." And Andy agreed with him.

For quite a time they soared aloft, Andy using the binoculars almost
constantly, watching the country below and occasionally sweeping the
distance.

Frank was thrilled to hear his chum suddenly give utterance to a cry,
but it was more of amazement than delight that gave birth to this
ejaculation.

"What is it now, Andy; more insurrectos?" he demanded, ready to
manipulate the planes and strike for higher regions.

"No, no, not this time," came the quick reply; "but Frank, as sure as
you live, there's that plagued old biplane just rising up yonder a mile
away. And somehow I seem to feel that it spells trouble for us."




CHAPTER XVI.


THE AIR CHASE.

One hasty glance told Frank that there could be no mistake. Only too
well did he know the construction of that same biplane that had in the
near past competed with them for honors in the race for Old Thunder
Top's crown.

"You're right, Andy," he said, earnestly; "and it seems to me they're
heading for us right now. What do you make them out to be? Can you see
who is handling the wheel? Is it Puss Carberry?"

"Yes, I'm dead sure of that; but Frank, there's somebody else with him!"

"Sandy?" asked his chum.

"No, it can't be. There, I had a good look at him, and Frank, he's got a
beard! It's a man!" answered Andy, in tense tones.

Frank's first action was to move a lever that would change their course
and place the biplane directly behind them. His next was to throw on
more speed, so that the faithful little motor started to humming with
the old-time rapidity that reminded Andy of the occasion when they put
it to its best efforts in order to rush ahead of their rival of the air.

"Then we must guess from that Puss and Sandy have fallen into the hands
of the rebels, since there are no government troops up here, the señor
said," he observed, presently. "Are they gaining on us now, Andy?"

"I don't think so," replied the one who held the glass, "though Puss
seems to be getting a whole lot of speed out of his Gnome engine right
now. Reckon he must have overhauled it, or else found some way to put
her up another notch."

"How strange to think that our old rivalry is being renewed away down
here in this country, thousands of miles from home," remarked Frank,
after a while.

"Huh! seems to me there would be something doing if you happened to run
across Puss Carberry at the other side of the world," declared Andy.

The race kept up for some time, neither seeming to gain to any
appreciable extent. Of course both boys were keyed up to a state of
intense nervousness. Passing through the air at this fearful speed fully
five hundred feet above the ground was surely enough to excite them. One
little accident and they would hardly know enough to give a single shout
of horror before the end must rush upon them. And yet Frank appeared as
cool as though sitting beside a camp fire, laying out some contemplated
air cruise on paper.

Andy was full of complaints.

"Aw, now, whatever do you suppose those measly old insurrectos want to
chase us for in this style?" he growled. "We're attending to our private
business and not bothering them one little bit. Why don't they leave a
fellow alone? Goodness knows we've just got trouble enough on our hands
without this."

"I don't know," said Frank, reflectively, "but I reckon they either want
our monoplane or else believe we're in the employ of the government, and
have been sent up here to spy on their movements. Anyhow, it seems plain
that they mean to make a big effort to get us."

"Which they won't, if we know it!" cried Andy. "But see here, Frank,
that chap is nervy, all right, going up with Puss and standing all this
racket. A tenderfoot is generally rattled even with a slow flight. He
seems to be holding out."

"I've been thinking about that," replied his chum. "And Andy, it looks
to me as if that fellow must know something about aviation. If I could
only glimpse him through the glasses I'd soon tell, for he'd show it by
the way he sits there alongside Puss. A new beginner would be hugging
the upright for dear life, and showing all the signs of fear."

"Yes, I know, because I did that same," answered Andy, once again
raising the binoculars as he twisted his head around.

"How is it?" asked Frank.

"Not much signs of fright about him, as far as I can see," came the
ready reply.

"Then make up your mind he's been up in an aeroplane before. Perhaps
he's some French or German, who has thrown his fortunes in with the man
who wants to sit in the presidential chair at Bogota, and in his own
country he must have seen something of aviation. Oh, well, it doesn't
make much difference to us. We just have to keep them at a distance and
take our chances."

"But Frank--"

"Yes, I know what you're going to say, Andy; that night will soon be
coming swooping down on us. That's so, and I'm sorry in one way, for
it's going to be a tough old job finding a suitable place to fold our
wings on in the darkness. But we're up against it good and hard, you
see, and it's what you might call Hobson's choice."

Andy showed more positive signs of anger.

"What business have they got bothering us this way?" he grumbled. "Say,
don't you suppose it would be all right for me to try a few shots at 'em
with the fine Marlin repeating rifle we're carrying? Perhaps I could
give 'em a scare anyhow and make 'em haul off."

"No, I wouldn't think of it," replied Frank, hastily. "You might cause
trouble to our own delicately balanced little aeroplane by firing. And
then again, what if you brought about an accident and sent them down to
the earth like so many stones?"

"But you know those other chaps banged away at us and they didn't bother
their heads a cent whether they upset our whole business or not,"
objected Andy, belligerently.

"Two wrongs never make a right, Andy."

"But when they opened fire on us," the other went on, complainingly,
"that constituted a declaration of war, and so you sec, we'd be quite
justified in giving 'em back the same kind of medicine."

"You forget that one of those two in the biplane is a former schoolmate
of ours and that perhaps he's just being compelled to chase us right
now," said Frank.

"Think so, do you?" growled Andy, above the rattle of the exhaust;
"well, I'd like to warrant you that Puss Carberry is grinning right now,
because of the fright he thinks he's giving us. No, sir, he's only too
willing to do anything to upset our plans. I know him pretty well, and I
wouldn't put any meanness past that fellow."

Frank in secret did begin to feel more than anxious. The afternoon was
almost over and the sun perilously near the western horizon. Too well
did he know how rapidly darkness came after the disappearance of the
king of day.

He bade Andy pay more attention to the lay of the country ahead of them.

"We're keeping well ahead of the biplane," he observed, "and there's
little danger of their overtaking us. But in case they drop out of the
race we must try and know something of the chances for a landing
ourselves."

"Gee! it looks pretty punk down there!" admitted Andy, after he had
carefully turned the glasses forward and down.

"That's what is bothering me," Frank said. "We've sure got to drop,
sooner or later, because it would be utterly impossible for us to keep
afloat all night. And if there happens to be no opening in that dense
forest, how can we land?"

"Listen! as sure as you live they're trying to wing us with a shot!"
cried Andy.

"Well, I wouldn't bother about that. The fellow only has a revolver, if
I know the sound of one, and he could never reach us at this
distance. It tells me that he's got to about the limit and that
something is going to change pretty soon, mark my words, Andy."

Of course one of Frank's objects in saying this was to encourage his
chum, for he knew that in all probability Andy was getting pretty close
to what he himself would call a "blue funk."

Sure enough the reports continued until just six had reached their ears
faintly.

"That ends it," observed Frank, complacently.

"And he never touched us," echoed his cousin, evidently with more or
less relief.

"Now take a look back and see what they are doing, Andy."

"H'm! still coming right along at top-notch speed," replied the other.

"All right. There's going to be a change soon. Look down, Andy."

"Oh, Frank, what a dandy open space! If only that plagued biplane was in
Guinea, how easy we could spiral down and make a landing there!"

"Yes!" said Frank, "And, mark me, that is just what they intend
doing. As for us, we'll have to move along further into the wilderness
and hope that another chance will come to let us out before everything
is blotted from sight by utter darkness."

"Frank, they've just sighted the open spot!" cried Andy, a few seconds
later.

"All right, what did I say?" demanded his cousin.

"They've given up the chase, sure!"

"And are about to drop down to make a landing for the night; is that
so?" asked Frank, eagerly, for their own chances were getting poorer
with every passing minute and secretly he was more worried than he chose
to admit.

"Just what they're doing right now, beginning to spiral down. Puss and
his old biplane weren't in it again with our dandy little Bug. There
they go, Frank. Don't I wish we had as good a place to grab hold of the
old earth!"

"Well," Frank continued, gravely, "turn around and look your prettiest
for it, then. Don't let even a half way decent spot go by. Any port in
a storm, the sailor says, and that ought to apply to the airship tar
just as well. See anything yet, Chum Andy?"

"N-no, can't say that I do," came the reply, as the other eagerly bent
his gaze on the tree tops that they were beginning to approach closer,
for Frank had turned the lever of the deflecting rudder in order to
start the monoplane earthward.

And the more they dropped the lower the sun seemed to get, until part of
his glowing disc appeared to touch the horizon.

Already it was growing dusk below them, and the dense foliage of the
interlocked branches of the trees seemed to offer an insuperable barrier
to a successful landing.




CHAPTER XVII.


THE CAMP IN THE TROPICAL JUNGLE.

"Frank, this is tough luck!" Andy exclaimed, presently.

"Keep up your spirits, old fellow!" called out the other, cheerily. "Has
the biplane succeeded in making a landing yet?"

"I guess so," replied Andy, moodily. "Can't see any sign of her back
there. And besides, it's actually getting dark down below, even while we
can see a bit of the sun up here."

"That's because of the contrast. I'll drop still lower, so we'll just
clear the top of the forest. Then you won't need the glasses, Andy.
Both of us must keep a clever lookout for a chance. Every now and then
there happens to be some opening in the forest, you know."

"Don't I hope we find one, though," declared the other. "Oh, wouldn't
it be too mean for anything, Frank, if we smashed the precious little
machine just when we are at the last stage of our big undertaking? If I
lived through it I'd be broken hearted sure."

"Look, then," said Frank, earnestly, "and you take the right, while I
keep an eye on the left. Both of us can watch out ahead. If it comes at
all to be of any use, it's got to be found inside of the next five
minutes!"

"So soon as that?" echoed the other, in distressed tones. "Oh, I'm
afraid we're in for the very worst experience we ever met up with."

"Ha! hold on, Andy. What's that dead ahead?" cried Frank, who suddenly
decreased the speed of the little motor.

"It's an opening of some sort, though awful little!" ejaculated
Andy. "We can never do it, I'm afraid, Frank."

"We've just got to, no matter what chances we take. Hold hard now and if
you can jump out in time, help stop her before we wreck her against a
tree."

Even while speaking the air pilot was starting to drop down. He had made
a specialty of this part of the business, knowing how very important it
must always be to aviators. The rise was nothing compared to the
descent, for many a gallant aircraft has been injured or even wrecked by
clumsy manipulation, want of room or some other cause while landing
after a flight.

Andy gripped hold of an upright. He tried to see down into that little
slash in the great forest, as though it might hold every hope connected
with his fortunes and the success or failure of his mission of mercy.

"Oh, be careful, Frank!" he called, as they just barely missed the top
of a great tree.

There was no need of saying this, as Andy ought to have known. No one
could possibly be more careful than Frank Bird. And yet this was one of
those times when daring had to go hand in hand with caution. The space
in which they meant to try for a landing was so very small that it
seemed necessary for the aeroplane to come down almost as lightly as a
feather.

Fortunately the youthful pilot possessed a good pair of eyes. And the
gloom had not as yet entirely blotted out all features of the landscape,
now that they were so close to the earth.

Andy was holding himself in readiness. He knew that there would perhaps
be an opportunity for him to drop to the ground and by pulling back,
help to bring the little airship to a full stop before they banged up
against a tree at the further side of the little glade.

Never before had Andy found himself compelled to do such a queer
"stunt," as he afterwards termed it; but he was braced to exert himself
now to the best of his ability.

"Jump!" shouted Frank, as they came roughly in contact with the ground.

And Andy went. He never knew whether he jumped purposely or lost his
grip of that upright after the shock of the collision; but the next
thing he realized he was straining himself with might and main to hold
back the monoplane, already gliding along with sundry violent bumps, on
the three bicycle wheels.

"Hurrah! What did I say?" cried Frank, as the aeroplane came to a
complete standstill close to the other border of trees.

There was a frightened series of grunts close by and some big unwieldy
animal went rushing away through the dense undergrowth, crashing along
as though badly frightened at this queer thing that had dropped down
from the sky.

"Wow! whatever was that, do you know, Frank?" cried the one on the
ground.

"I don't know for sure, because I only had the least peep of something
that looked like a small elephant making off," replied the other, also
alighting.

Andy was already reaching for the repeating rifle, which had been
securely fastened in the frame of the monoplane.

"But Frank, they don't have such things as elephants down in South
America?" he expostulated.

"Sure they don't," laughed Frank, feeling particularly good over the
grand success that had attended their perilous landing. "Nor a
rhinocerous, nor a hippopotamus; but they do have the next largest
beast, and that's a tapir. He's something like a big pig and not very
dangerous, the señor said. That was what we frightened off just now, I
reckon."

"Well, here we are on land again and mighty lucky to get down without
some sort of a smash. Frank, you don't think anything was broken when we
struck, do you?"

"Of course I can't say for sure, but I believe not. But all the same I
must give a good look in the morning before we make another start," was
the reply Frank returned.

"And now we're just got to stay here all night?" remarked Andy, who
still held the gun in his hands.

"That isn't anything. We'll soon have a cheery blaze started that will
keep the prowlers away, I guess. Get busy, Andy, and see what we can
do. But we'll start it some distance away from our gasoline tank,
remember."

"But won't they be apt to see a fire?" asked the other, as he
reluctantly placed the rifle down and started to gathering wood, no easy
task in the increasing darkness.

"Do you mean Puss and that other fellow?" Frank asked, with a
laugh. "Oh, they're a mile or two off, and even if they could see the
biggest of fires I'd defy them to get half way here if they took the
whole night to cut their way through that mass of trailing vines and
brush. Don't bother your head about that crowd, Andy. I hope we're done
with them for good."

His reassuring words seemed to have considerable effect on his cousin,
who up to recently had himself been a most cheery fellow.

"Well," he said, "we've sure got a whole bunch of gratitude on tap for
the lucky way we dropped in here. Chances looked twenty to one it
couldn't be done. And I'd like to wager that no other air pilot could
have made the ripple so well."

"You're prejudiced, old fellow, because I'm one of the Bird boys,"
laughed Frank as he struck a match and applied it to the bunch of dead
grass he had gathered in the spot selected for their fire.

It was a dozen yards away from the aeroplane and about the same from the
nearest line of great bushy trees. Immediately the flame sprang up,
dispelling the darkness to some extent.

"Shucks! but that makes a big improvement and no mistake," said Andy,
stooping to drop some wood on the fire. "I always like to see what I'm
doing. And more than ever when I'm in a strange place. Hark! what was
that, do you suppose, Frank?"

A sound had come from the depths of the forest not unlike the wailing of
a babe. Frank could give a guess what made it, but he did not
immediately say so.

"Say, we must have landed close to some native shack, and that's a baby
crying!" Andy declared.

"Hardly," came from Frank. "That's only one of our cat friends giving
tongue, perhaps calling to his mate to come and see the funny objects
that dropped from the skies."

"Wow! reckon now you must mean a yellow boy, a jaguar! I bet you, Frank,
there's a heap of 'em around us right now. How do we know but what every
tree hides one of the critters, watching everything we do? I can tell
you right now that I don't wander far from this jolly little blaze
tonight. And besides, one of us has just got to keep a grip on this gun
all the time. I don't hanker after being carried away and made a meal of
by a big hungry cat."

"Oh, the fire will scare them away all right, I believe. There isn't an
animal that doesn't dread fire. Always keep that in mind, Andy, when
trouble comes," said Frank, earnestly.

"I mean to," replied the other, as he once more started to pick up wood,
but it could be noticed that while doing so Andy always kept on eye on
the alert, as if he really believed what he had said about the chances
of their being watched by an army of jaguars.

"There's another sort of cry, Frank," he remarked, presently.

"Yes, and although I couldn't say for sure, I believe it is made by a
colony of monkeys, traveling through the woods at night," the other
replied, after stopping to listen for a minute to the odd sounds.

"Monkeys!" cried Andy, smiling broadly. "Well, I declare I had
forgotten that they have them all through the tropical regions around
the Orinoco, the Magdalena and the Amazon. And so that's a menagerie
traveling over the treetops, is it? Wish I could just get a look."

"Well, I don't think they're far away," remarked his chum.

"Not for me. I know when I'm well off. This camp looks good enough,
without my wandering around in that awful place. Let 'em jabber, and the
yellow cats snarl; but Andy Bird stays right at his fireside tonight."

"And I guess you're right," said Frank, as more noises arose all around
them.




CHAPTER XVIII.


WHEN FRANK STOOD GUARD.

Pretty soon things began to look fairly cheerful in that lonely glade
situated in the heart of the tropical forest. A fine fire crackled and
shot up its red flames, lighting up the opening in which the young
aviators had so luckily alighted.

Andy was bending over the fire making a pot of coffee, for they had
brought along with them the necessary cooking utensils, including a
frying pan, not knowing how long they might be adrift in the wilderness,
far from the domicile of any human being.

"How do you find it?" he sang out, for his chum had been examining the
aeroplane as well as possible under the circumstances.

"Everything seems to be hunky-dory," came the reply. "I'm going to start
up the engine now to see if it works without a hitch."

"Don't I hope so," was what Andy said, as he paused in his task to
watch.

A minute afterward he gave a little cheer, as the familiar throbbing
sound was heard, making the sweetest music that ever greeted the
listening ear of an aviator.

"That sounds good to me, Frank!" he cried.

"Nothing wrong about it, thank goodness!" came the reply of the other,
as he again shut off power, because they could not afford to waste a
drop of their valuable supply of gasoline.

"Well, suppose you drop in here and sample this brand of coffee. What
with the cold snack we brought, and which still holds out, we ought to
get along right decently, Frank."

"I tell you right now," replied the other, as he came up, "I'm hungry
enough to eat anything going; yes, even some of our native cook's worst
garlic-scented messes. And that coffee just seems to make me wild. Shove
a cup over this way as quick as you know how, brother. Yum, yum, that
goes straight to the spot. And this cheese and crackers isn't half way
bad, even if it is pilot biscuit."

"Well," said Andy, "ain't you a pilot all right, and don't they feed
sailors on this hard tack generally? Sure we've got no kick coming.
Everything is to the mustard, and if you asked me my opinion right now
I'd say things are coming our way."

"Listen to that chorus, would you?" remarked Frank, as various sounds
arose all through the dense timber around them; "they seem to be heading
this way sure enough."

At that Andy reached again for the gun on which he seemed to depend so
much.

"Well, if any of 'em take a sneaking notion to look in on us, why I'm
meaning to use up a few of these flat-nosed cartridges in this six-shot
magazine," he remarked, sturdily, as he glanced cautiously around.

"No fear of that now," said his chum, reassuringly. "The danger will
come, if it does at all, later on, when we have more trouble keeping the
fire going. So after we get this supper down we shall have to gather
fuel. It may not be quite so nice to go after it when we see a line of
yellow eyes watching all around."

"Oh, shucks! You're just stringing me now, Frank. If I really thought
they'd be as bold as that, why I'd climb a tree, that's what."

"What good would that do, tell me?" jeered the other. "Why, these cats
just live in trees and can leap twenty feet if they can one. Perhaps if
you found a hollow tree now you might feel safe, but in the branches of
one--never! Why, the monkeys would come and laugh at you. The ground
is the best place for us, after all, Andy."

"More coffee in the pot, if you ain't afraid of staying awake,"
suggested the cook.

"That would just suit me, for you see I'm more afraid of going to sleep
than anything else while on guard duty," Frank remarked, soberly.

By degrees Andy realized that this business of camping in the heart of a
tropical forest was no laughing matter. Still, they had escaped so many
threatening perils that he was beginning to believe they must be under
the protecting wing of some favoring god and that success lay just
ahead.

They sat up and talked for a long time. Neither would admit being at
all sleepy, and yet Frank caught his chum yawning ever so many times.

"Here, you, just make up your mind to turn in and get seven winks," he
said, pretending to be giving orders with all the airs of a commanding
officer.

"I suppose I'll just have to," came the reply, as the other started to
roll up close to the fire, for they had no blankets with them this
time. "Do you know I was just thinking about Puss."

"Well, what of him?" asked Frank.

"What if they start to chase us again in the morning? Are we going to
put up with that funny business right along? I say no. Let's warn 'em
that we're armed and can bore a hole right through their jolly old
biplane, upsetting them any time they get close enough. I'm drawing the
line on tomorrow, because somehow I feel it in here that it's going to
be the greatest day of my life," and Andy laid his hand on his heart as
he spoke.

"Yes, that would be our best plan," admitted Frank. "We've already stood
quite enough of that funny business, as you call it. They even fired at
us. Depend on it, Andy, they won't follow us very far next time."

And Andy, seeing the way his chum's mouth was firmly set, made up his
mind that Frank had reached the end of his patience. Contented with the
prospects for the morrow he therefore lay down to get some sleep.

"I say, Frank," he called out presently.

"Well, what now?" asked the one on guard, who had possession of the
rifle and had taken up his position so that he could have a clear view
of the open space all about the camp.

"If one of the prowlers tries to drag me off, remember I've got my leg
tied to this stake I knocked into the ground. While he's tugging you can
have a bully good chance to knock him over, see?"

"All right," grinned Frank. "I'll remember. But let out a whoop if you
feel yourself going. I might be looking the other way."

"You just bet I will," mumbled Andy, curling himself up as near the fire
as he dared creep.

And in three minutes Frank knew from the heavy breathing coming from
that quarter, that his chum had found no trouble in getting to sleep,
regardless of the various sounds welling up from the neighboring forest,
and the fears that possessed his boyish soul.

Frank sometimes sat down; and again, feeling cramped in this position,
he would rise to his feet, and walk back and forth. But all the time he
kept the gun in his possession, with the hammer pulled back, ready for
business. And constantly did he maintain a close watch along the nearer
border of the undergrowth that lay there, so dense and filled with
mystery.

Time passed on.

It seemed as though a thousand things flitted through the active mind of
the young aviator as he thus stood guard over the camp. Once again he
was back in good old Bloomsbury, where he had spent so many happy
days. He could see the faces of his boyhood friends, Larry, Elephant and
others.

Frequently he would detect a movement here or there among the trees; and
at such times he could easily imagine that some animal belonging to the
forest was creeping closer in. The question was, whether simple
curiosity urged them to do this thing, or a design upon the occupants of
the camp.

Frank had been in other situations calling for considerable pluck, and
never failed to meet the emergency, nor did he now.

It must have been some three hours back that Andy lay down to
sleep. That had been the limit of time arranged upon; but Frank did not
show any signs of intending to awaken the other.

"Let him sleep," he said to himself, as he walked up and down, for by
now he was beginning to feel very drowsy himself, in spite of the
coffee. "He needs it more than I do. And besides, I'm a little dubious
as to what sort of watch Andy would keep. Anyhow, I can stand it a while
longer. Hello! what's that mean?"

His attention had been attracted toward a movement in the brush at the
nearest point of the forest. It was not thirty feet distant. Could one
of those long-bodied muscular jaguars cover that distance in a wild
leap? What if without warning he should see a tawny figure flashing
through the air, and headed straight for him?

Frank threw the gun up to his shoulder as if to try and see how readily
he could cover such a flying form. As he did so he heard a low and
ominous growl, which undoubtedly sprang from the very spot where he had
just caught that suspicious movement.

He bent his head to look closer, and as he did so an exclamation fell
from his lips.

"And that's no owl staring at me, either," he said to himself, as he
caught the singular glow of what seemed like two balls of fire, just
under the lower growth.

Frank knew what they undoubtedly must be. He had seen the orbs of a cat
shine in this phosphorescent way in the darkness. There could be no
doubt but that he was being surveyed by one of those savage beasts whose
whining he and Andy had heard around the camp for hours.

"And I declare if that purring sound doesn't come from there, too," he
muttered, as he sank down upon one knee, the better to aim his
rifle. "What was that the old señor was telling me about these beasts?
Didn't he say they jerked their tail to and fro like a pendulum, and
made a queer noise just before they jumped? If that is so then this
fellow is getting ready to leap over right now. Time I was doing
something, if I don't want him to drop on my chum like a rubber
ball. Well, here goes to take him between those yellow eyes. Steady now,
my boy, steady!"




CHAPTER XIX.


FIREBRANDS AND JAGUARS.

"Bang!"

"Wow! are they coming in on us?" shouted Andy, suddenly aroused by the
sharp report of the repeating rifle.

He bounded to his feet, and from his manner of action it was plain to be
seen that he remembered exactly the condition of affairs at the time of
his taking passage for the Land of Dreams.

Frank had aimed straight between those glowing eyes at the time he
fired. And as he was perfectly calm at the time, it stood to reason that
his bullet went direct to the mark he meant it should.

He saw a yellow object threshing about under the dense growth, and
realized that he had given the adventurous jaguar something that was apt
to wind up his career as a terror to the monkey hosts of the forest.

But this was not all Frank saw. Another figure had appeared just ten
paces farther along, and he realized that a second jaguar had crept out
of the copse, evidently bent on charging the camp.

"There's two more, Frank! Oh! my, it's a dozen I guess!" whooped Andy,
who had found a better opportunity to see in other quarters.

"Grab a firebrand, quick!" shouted Frank, trying to get a bead on the
second slinking figure; and yet hesitating about firing, because of the
great risk that must ensue should he only wound the fierce monster.

He saw out of the corner of his eye that Andy made a plunge toward the
fire and was snatching a brand out in each hand.

"Wave them around your head, and shout like thunder!" he cried, at the
same time starting in to do this latter himself.

Perhaps it was a comical thing in some respects. Andy often laughed over
it afterwards; but just then it seemed serious enough. The way both of
them let loose with their strong young voices would have made a football
cheer captain turn green with envy. They fairly awoke the echoes
slumbering in the depths of the forest.

And Andy waved those two torches like a good fellow, back and forth, in
and out, weaving them as an expert Indian club athlete might do with his
heavy weights, until the rushing flames roared again and again because
of their rapid passage through the air.

"They're licked already, Frank!" whooped Andy, as he daringly began to
advance with his flaming beacons swinging around and around. "Look at
the coward moving back, would you? Talk to me about your guns, they
ain't in it with these things, when it comes to scaring off a pack of
wild beasts. Scat! you terror, or I'll just swat you one alongside your
jaw. Growl at me, will you? There, take that, hang you!"

To the astonishment of Frank, Andy, who had rushed straight at one of
the retreating animals, suddenly hurled a blazing brand straight at the
jaguar. In his palmy baseball days Andy had never amounted to a great
deal as a pitcher; but all the same he made a beautiful throw right then
and there.

The whirling, blazing fagot of wood struck the slinking beast full in
the side. Frank threw up his gun, ready to shoot should the jaguar, as
he feared might be the case, leap at his chum. But there proved to be no
need. Instead, the brute was evidently alarmed at this novel weapon,
something entirely beyond his ken.

Frank heard him give a snarl that told of mingled rage and fright. Then
he made a spring, but _away_ from the fire, and into the dense
undergrowth from whence he had just issued so bravely.

Looking around Frank saw that the glade was deserted of four-footed
foes. The whirling torches had done the work.

"Bully for us!" shouted the excited Andy, ready to dance in his delight
over the success of his labors. "Didn't we send 'em a flying, though?
Perhaps they just dare to come snoopin' around here again, when they're
not asked! Frank, I guess you nailed that critter, all right. Dast we
look and see?"

"Sure we will," returned Frank, instantly. "Pick up another bit of
burning wood. Then let me go just ahead of you, so that I can shoot if I
have to."

They thus boldly advanced toward the spot where Frank had first sighted
the blazing yellow orbs.

"I can see something there!" declared Andy, who possessed sharp eyes.

"Yes, it's the beast, all right. But I can't say for sure whether he's
down on his back, or crouching for a spring. Careful, not so fast,
Andy." And Frank kept covering the object with his rifle as foot by foot
they kept on.

"He's lying on his side! He's a dead duck, all right!" sang out Andy,
waving his fire vigorously to and fro.

"You're right, he's stone dead!" observed the other, a touch of natural
pride in his voice; for it was no mean feat to kill so ferocious a beast
as a jaguar, after seeing only his two eyes shining in the darkness
beyond the fire-light.

Frank stooped down, and catching hold of one of the dead animal's hind
legs, started dragging it toward the fire.

"Hold on there," said Andy; "don't tell me we're going to have a steak
off that old cat? I can stand for a good deal, but I'd go hungry a long
time before I'd eat any of _him_!"

"Don't worry about that," laughed Frank. "But think what a bully old
rug his hide will make some day. I'm going to try and take it off, if I
can, while you're getting breakfast in the morning. It's worth while."

Andy looked as though he doubted the ability of his chum to accomplish
the feat; but then he was counting without his host; for when the chance
came Frank deftly removed the pelt, and kept it for a reminder of his
hazardous shot.

Andy insisted on taking his turn at playing guard, when he found out
what time it was. First of all Frank saw that the fire was revived,
with plenty of fuel handy. Then, after giving his chum a few last
instructions, he consented to lie down. But his sleep could not have
been very sound, for frequently he would raise his head, and take a look
around; seeing nothing suspicious he would again lie down.

So the night passed away.

Frank was on deck an hour and more before the dawn came. He felt too
anxious concerning the possibilities of the coming day to sleep much.

So Andy started to get breakfast, such as it was, before the night had
really gone. He excused himself by saying that while he was not at all
hungry, the operation had to be gone through with, and the sooner he was
at it the quicker they might be free to mount upward.

Frank knew what a terrific load was on his chum's mind, and how he
thrilled with suspense, now that they were so near the realization of
his highest hopes or worst fears.

And so he too set to work to remove the jaguar skin, for it would make a
pretty decent rug, if it could be properly preserved.

Morning was just breaking as they sat down to partake of the simple
meal. Neither of them seemed to care for much. It was indeed no time for
feasting, or making merry, when the day had probably dawned that was to
settle their mission, one way or the other.

"One thing good," remarked Andy, hopefully, "there doesn't seem to be
any strong wind blowing this morning."

Frank had been studying the lay of the land in the glade.

"I tell you we're going to have all we can do to squeeze up out of here
without scraping against any tree before we can rise above them," he
observed, presently.

"But don't you think we can do it?" demanded his chum, anxiously
watching his expressive face.

"I think it is possible," came the slow reply; which after all gave Andy
new cause for distrust; since his cousin was so cautious a fellow that
he seldom if ever gushed over anything; at the same time he never
expressed doubts when he felt positive.

"But!" cried Andy, "there's no other way to fly; we couldn't take the
aeroplane to another place; and I reckon there isn't a cleared field
within ten miles of here."

"No, it must be done right where we are. Now, I'm going to measure the
opening to find out its widest dimensions. Then we will take the
monoplane as far back as we can, and make all arrangements for a rapid
start. But to rise above those trees, even the shortest of them, is
going to call for considerable management, and some great good luck in
the bargain."

"But, Frank, you've done it before," declared Andy. "You know you made
lots of short starts that beat all the records. That's your best
hold. And, Frank, we've just got to get out of here. Everything depends
on it."

"Sure," responded Frank, cheerily enough; "and we'll manage somehow,
never fear. Now to foot off the space. Count to yourself, and we'll
compare notes when I get to the other side. This looks the widest range,
according to my eye."

So they both started off, Frank placing one foot close in front of the
other, and Andy keeping alongside in order to do his own counting. In
this way they passed from one side of the glade to the other; and Frank
was secretly pleased to find that the distance was considerably more
than he had judged possible.

Besides, the trees happened to be much lower on this side, which fact
would be of considerable benefit to them when they started to make the
run, and rise.

Frank was still muttering the number of feet to himself, and had arrived
within something like five yards of the nearest trees, when, without the
slightest warning, he heard Andy let out a screech that could have but
one meaning.

He had surely sighted something that spelled peril to one or both of the
Bird boys. Frank had wisely kept the rifle in his hand, and instinct
caused him to throw this up to his shoulder, though as yet he had not
the slightest suspicion as to what the nature of the danger might be,
nor the quarter in which it lay.




CHAPTER XX.


THE AEROPLANE BOYS ONCE MORE AFLOAT.

"Frank! Oh! Frank!"

More than a few times had it fallen to Frank Bird to drag his cousin and
chum, Andy, back from some impending danger. Now the shoe seemed to be
on the other foot.

Even as he looked hastily up, startled by these sudden cries, Frank felt
his arm seized in a frenzied clutch, and himself jerked backward.

"What is it, Andy? Here, hold on, let my arm free, and tell me!" he
exclaimed.

"Look there; and you were going to walk right up against it! Oh! Frank,
what a horrible monster!" Andy replied, in trembling tones, as he strove
to point toward something that he had seen just in the nick of time.

"Whew! I should say you were right! Ain't he a dandy, though? And if I
saw him at all, I thought it was a great big vine hanging from that
tree! Ugh! look at him stretch his mouth, would you? Andy, thanks to
your sharp eyes I'm here, instead of in his slimy folds. I guess he
could crush an ox. They say nothing can stand the pressure, once they
get a couple of folds around."

"Is it a python?" gasped Andy, his horrified eyes glued on the spectacle
of the slightly swaying ten feet of snake that hung from the limb of a
great tree, in part as thick as Frank's thigh.

"About the same thing," replied Frank. "Down here they call them
anacondas, and in other parts of the world they're boa-constrictors. I
guess the whole bunch belongs to the same family of squeezers. But that
fellow is in our way."

"Well, yes, if you're still determined to run the aeroplane across lots
toward this side of the opening," Andy remarked with a shudder. "Why,
perhaps that old chap might get gay, and grab hold, just when we
expected to go sailing off. That would be a calamity, not only for him,
but the Bird boys in the bargain."

"All right. Then he's got to get his," Frank observed.

"What are you going to do?" demanded the other, nervously.

"Take a crack at his head," came the reply. "Once let a flat-nosed
bullet from this little Marlin hard shooter smack him on the coco, and
there'll be a funeral in the anaconda family."

"But for goodness' sake make sure work of it, Frank. What if you just
wounded the monster? He'd come whirling along at us like a
hurricane. And I'm sure he must be thirty feet long, if he's a
dozen. Look at the thickness of his neck, would you? Be mighty careful,
for his head's swinging a bit, you notice. That was what made me get
sight of him. Say, Frank!"

"Well, hurry up. He may take a notion to move off, and I'd lose my
chance, Andy."

"How'd it do for me to get some fire, and shoo him away?" suggested his
cousin.

"Don't know how it would work," replied Frank, smiling a little,
however, at the faith Andy seemed to have in a blazing brand, now that
he could look back to his late experience with the jaguar. "Never heard
that snakes were afraid of fire. And besides, there's no need. Now keep
quiet, and watch. You'll see something worth while; but be ready to jump
clear."

He had already dropped down on one knee. The Marlin stock rested
against his cheek, and his eyes sighted along the barrel. Andy fairly
held his breath, his startled eyes glued on that swaying head of the
monster.

Then came the sharp report as Frank pulled the trigger. He instantly
jumped back, and by a rapid motion of his hand sent another cartridge
into the chamber, the clever mechanism of the gun proving that it was
built so as never to fail in an emergency.

Andy had accompanied his chum in that backward movement; but never for
an instant did he remove his eyes from the strange spectacle that was
taking place there in front of them both.

Undoubtedly the well aimed bullet had crashed through the fearful head
of the suspended anaconda. Instantly it released its many coils above,
and a tremendous length of writhing snake could be seen whipping over
the ground. Nothing in the way of small vegetation could stand in the
path of those powerful springy coils, as they shot this way and that.

"Oh! my!" gasped the astounded Andy, as he moved farther back, so as to
avoid any chance contact with the flying destructive force that was
leveling everything in the glade for twenty feet around. "Did you ever
see anything to equal that? Talk to me about your harvesting machines,
here's one that's got 'em all beat to a frazzle. Ain't he ever going to
give up the ghost, Frank? Guess these anacondas must have the nine lives
of a cat!"

"Well," remarked Frank, "you must have forgotten that among boys it's
said that a snake won't die till sundown. I've seen one's tail wiggle
hours after we thought the thing was stone dead. There, he's moving off
into the forest, and a good riddance. While I'd like to measure the
serpent just from curiosity, we've got no time to waste waiting for him
to kick the bucket."

"That's right," assented Andy. "And as for going anywhere near such a
whirlwind, you'd have to excuse me."

They watched the dying anaconda gradually vanish in the depth of the
forest; and both boys were glad that it had turned out that way, since
they were anxious to depart from the place.

"Don't I wish I'd had my little camera along, so I could have snapped a
shot at that dandy chap! The fellows would believe me then, when I told
about what happened to us here. And anyway, Frank, I don't think we'll
forget this camp, do you?"

"Well, hardly," replied his chum, smiling broadly. "Because we've sure
had enough happen to us here to make us remember. But I'm glad to find
there's going to be more space for the run than I thought at first."

"We'll need every inch of it," declared Andy, as he looked dubiously at
the tops of the lower trees about the place where the snake had held
forth. "Don't I wish we'd brought a few sticks of dynamite along,
though."

"For goodness' sake, what would we want with dynamite? Think you could
have blown up that snake, do you?" asked Frank, as they started to cross
the glade toward the waiting monoplane.

"Oh! shucks, no. I was thinking how we could plant 'em under a bunch of
those trees and enlarge the gap!" declared Andy.

At that Frank burst out into a hearty laugh.

"What a fellow you are for wild notions. Think of us blowing up the
forest to make an aviation field! I reckon, however, seeing that you
haven't got the dynamite, Andy, we'll have to do the best we can. Take
hold here and we'll push the machine just as far back as it will
go. Perhaps we can gain a few yards at this end that will count in the
long run."

Frank was particularly careful about every little detail. He knew just
what he had to depend on. In the past he had made it a pet hobby to rise
in as short a space as possible; and now this faculty seemed destined to
prove a valuable asset in their speedy climbing up.

"All ready?" he asked, grimly.

Andy took one last look at the face of his chum. He saw that Frank's
mouth was compressed in that firm way that stood for so much; and
somehow Andy's wavering confidence returned in full measure. When Frank
Bird looked like that, things always had gone according to his will; and
they must now!

"Yes, I'm fit, Frank," he said, quietly. "Let her go when you're ready!"

In the many times that the two boys had made ascents, Andy could never
remember that his pulses throbbed with one-half the suspense they did
now. Not even on that never to be forgotten initial performance, when
for the first time they felt the strange sensation of leaving the solid
ground in a flying machine, had he been so excited, so nervous, so
filled with alternate hope and fear.

Frank had taken every possible precaution. He had thoroughly studied
the ground, and made sure that no obstacle would be apt to cause the
running gear of the aeroplane to swerve, and thus throw them off their
course.

All he could do was to start the machinery, get a rise at the quickest
possible second, and be ready to shut off power if he realized that the
feat they were about to attempt were impossible, so as to avoid smashing
the planes against a tree.

"Then here goes!" he said, calmly.

Andy held his breath as he heard the engine start off at a tremendous
speed. He felt as though a giant hand had plucked them from the spot
where the aeroplane had been planted for the start. Across the glade
they went speeding. His heart almost jumped into his mouth he believed,
as he felt the little craft start to leave the ground, as Frank
manipulated the planes, and elevated them so as to catch the air under
the broad blades.

They were rising rapidly now! Would they manage to clear those terrible
treetops that stood like a grim barrier in their path?

Higher yet did Frank throw the planes, so that they actually seemed to
be climbing straight upward, according to the vivid imagination of Andy;
who, clutching the upright at his side, waited for what was going to
happen.

It was too late now to retreat! They had gone too far to stop, and try
again! No matter whether for good or ill, their kite had been tossed to
the winds of heaven, and they must abide by the consequences.

Andy gave one little squeal, for it could not be termed anything else
under the sun. This was when they shot past the most prominent branch of
the tree that happened to stand directly in the way of the rising
aeroplane. Andy believed that the wheels below must have actually
brushed through the foliage, for he always declared that he heard a
fierce "swish" as they passed.

Had they caught even one little bit, something dreadful might have
happened, and the precious aeroplane, on which everything depended, meet
its sad fate; not to speak of the nasty fall the Bird boys would have
suffered.

But Fortune was once more kind to the young adventurers. They passed
safely through the peril, and were speedily fully launched upon the wide
open expanse of space!

"Hurrah!" shouted the exultant Andy; but it might be noticed that his
voice was a bit husky, even as his face seemed chalky white.

"A close shave," remarked Frank; who himself had been rigid while they
were thus taking such desperate chances; "but we made it, thank
goodness! I hope that will be a lucky token of what the day has in store
for us."

"Amen!" echoed his chum; and there was no levity in his tones, either.

The sun was just rising. Below them lay the dense foliage of the almost
impenetrable forests, from which they had just made this almost
miraculous escape. And both young aviators, as if by common consent,
started to sweep the horizon around with their eyes.

"See anything of it?" asked Andy, eagerly.

"I thought I did away over yonder toward the mountains; but I guess it
must be a big bird hovering high up, a condor perhaps," Frank replied.

"Well, there isn't any sign of the biplane, that's sure," Andy went on
in a relieved voice. "Perhaps they didn't have as good luck in landing
as we did, and had a nasty spill. Don't I hope they busted some of the
planes, or part of the little old Gnome engine, so we won't have to be
bothered with 'em again?"

Frank made no remark. While as a rule he refused to let anything like
bitterness dwell in his heart, still, this was a case where everything
was at stake; and if the bothersome revolutionists kept chasing them in
the biplane they were apt to give a great deal of trouble. And secretly
he could echo Andy's wish that the biplane might be temporarily
crippled, so as to be unfit for flying.

"Now, what's the programme?" asked Andy, when they had covered several
miles.

"We've just got to head for the mountains yonder," replied his
chum. "You know, he declared it was a valley that lay among the
mountains; and it must be, to be surrounded by high cliffs. Once we get
among the hills, we'll sail back and forth, combing the whole region,
and hoping sooner or later to discover his queer prison."

Andy lapsed into a state of silence; but he kept watching ahead as they
drew gradually nearer the uplifts. Doubtless but one thought held
dominion in his mind, and this was that somewhere amidst those same
mountains the father whom he loved so dearly was waiting, and hoping for
an answer to his appeals for aid.




CHAPTER XXI.


THE LAST LITTLE HOT AIR BALLOON.

"Did you ever see a wilder region?" asked Frank, about the middle of the
morning, when they had alighted on a broad, level plateau, so as to
allow him to look over some little matters connected with the engine,
that he believed needed attention.

Andy had been using the binoculars pretty much all the time they were
aloft, but without any success. Many times be began to think he had
sighted something that looked like cliffs rising up, and a wild hope had
seized upon his devoted heart; but upon Frank bringing the airship in
that quarter, in answer to his frantic appeals, it had proven to be a
false clue.

Cliffs they saw in plenty, but as yet none enclosing a valley so as to
imprison an unfortunate aeronaut, whose runaway balloon had dropped with
him into its depths.

Still, the day was not nearly half over. And the monoplane behaved
splendidly; so that they could hope to continue the search as long as
their supply of gasolene held out.

"I'll never give up hunting," Andy declared, as he stood there, watching
his chum potter with the engine and examine things in general. "No, not
as long as this fine little machine stands by us. We can get more
gasoline if necessary, for we brought a good supply aboard the
boat. When we've gone as far as we dare down this way we'll make another
start further on."

"I'm with you, Chum Andy, and you don't need to be told that," observed
Frank, quietly, while he worked on.

"As if I didn't know that and counted on you through thick and thin,"
declared the other, with a look of sincere affection.

"Well, now we're ready to go up again," remarked Frank; "and there's no
use asking if you feel like it. So pile in and we'll make a flying start
from the top of this rocky plateau."

"What a difference from our last start," observed Andy, with
satisfaction, for they were on an elevation with a valley far below, and
the air was decidedly bracing for the tropics.

"I should say it was," laughed Frank. "Do you know what it puts me in
mind of?"

"I bet you're just thinking of when we won that race to the summit of
Old Thunder Top, where nobody had ever been able to climb before, and
how we had to make our start for home from that little plateau, plunging
off into space."

"Just what I was," declared Frank. "But here we have a longer swing and
it's going to be a snap of a launch compared with some we remember."

"Ugh!" grunted Andy, "will I ever forget the one this morning. But let
loose, my boy. I had just sighted a likely looking place away over
yonder, at the time you said we ought to take advantage of this fine
landing stage, to look things over. Just head her that way when we get
going, will you?"

"Sure; anything to oblige," assented the other.

The launch was just as easy as they had anticipated. Indeed, Frank
seemed to have gotten this part of the programme down to a fine point
and could accomplish it apparently as well as a Wright or a Curtiss.

Ten minutes later and the monoplane was soaring toward the region which
Andy had denominated as a "likely spot."

"Look at that big bird watching us from that pinnacle yonder!" exclaimed
Andy, as he lowered the glasses for a moment.

"I see him," replied his comrade. "And there's no doubt now but what
that is a condor of the Andes. He thinks we must be some sort of bird,
which we are, of course, and is wondering whether he ought to flap his
wings and go up higher or hide behind that church steeple of rock."

"I only hope he don't take a measly notion to fight us, that's all,"
remarked the other, as he glanced anxiously toward where the Marlin was
secured to the framework of the airship.

"No danger of that," Frank continued. "A condor is like our vulture or
buzzard, a scavenger; and he lacks the bravery of the bald-headed eagle
that attacked us when we came near his nest on the tip of Old Thunder
Top. Look there, he's off, Andy, and at a good lively clip,
too. Good-bye, old chap, and good luck!"

Andy had lost all interest in the great bird of the western Andes. He
was focusing his attention upon the place that he had marked as a likely
spot.

"Frank," he said, presently, in a husky voice, "could you drop a little
lower and slow down some?"

"That's easy," replied his chum, readily enough. "What has struck you
now, Andy?"

"It looks more and more promising to me," came the slow reply, as Andy
kept the glasses up to his eyes.

"Then you can glimpse something like cliffs?" asked Frank.

"Yes, and there's no doubt about that part. I'm waiting now to see if
the wide valley is wholly enclosed!"

"And if it is, you think--"

"It must be the place! Oh, Frank! What if we are near the spot? Would he
still be alive, or has he given up the fight? That condor perched up on
the pinnacle--was he only waiting for the time to come when he could fly
down? Perhaps--oh! what is that moving yonder? Look, Frank, Frank,
something is coming up above the top of the mountain! Can you see it? If
you could only take the glasses and tell me, for my hands are shaking so
I can't hold them!"

"Brace up, Andy. I can see what you mean without the glasses. There, now
it has risen above the line of rocks--something that bobs to and fro
like no bird ever flew--something that floats, now this way and now
that, just as the wind blows. Andy, upon my word I believe it is, it
must be--"

"Oh, say it for me, please, because I just can't find words!" cried the
other.

It was a wonder that in their tremendous excitement something disastrous
did not happen to the aeroplane, but Frank had wisely cut off some of
the power, so that they were just making fair headway at the time.

"It is a little parachute balloon, just like the one that carried that
message into the cocoa grove of Carlos Mendoza!" ejaculated Frank.

"Then it means that we have found the valley prison!" gasped Andy.

"Sure, that's a fact. The cliffs yonder are on one side of it!" Frank
cried.

"And Frank, don't you see, the fact that another of those little
messengers of hope has just come up out of the valley _shows that he is
alive_!"

"You just bet he is, Andy; and we're going to be with him in three
shakes of a lamb's tail!" declared the other.

Andy could not utter another word; he was too full of emotion. So he
just sat there and stared and waited, his heart doubtless thumping
against his ribs as it had never done before.

Of course, when Frank gave utterance to that boast he did not really
mean it, and only had the encouragement of his chum in view. He knew
that it was apt to prove a difficult task, landing in that enclosed
valley, where the vegetation must be of a tropical order.

First of all they must circle around over the wide expanse to take in
its features and discover the prisoner. Then Frank could lay his plans
accordingly.

Gradually they began to see more and more of those marvelous
cliffs. They seemed to stretch in an unbroken cordon completely around
the valley. If they were as near like adamant as they looked it would
take a man years to cut steps to the lofty top, even though he were
given proper tools for the work.

And presently they cleared the near side, so that the monoplane floated
directly above the valley itself.

"Careful now, Andy!" warned the cautious Frank. "Hold yourself tight
while we circle around, dropping lower all the time. Suppose you shout,
though I should think he'd have heard the noise of our exhaust before
now!"

He had hardly uttered these last words when there came a cry from below.

"Look, look, Frank, there he is! Oh, what a blessed sight that is! My
father, and alive after all! See how he runs and waves his hands! What
will he say when he knows that it's his boy in this airship come to save
him?"

"Call out and tell him!" said Frank, hardly able to control his own
feelings, though he knew he must or they might meet with an accident in
this supreme moment of victory.

So Andy did shout, calling upon his father wildly and waving his cap to
him. The prisoner of the enclosed valley seemed dazed at first. Perhaps
he had been deceived so many times by his dreams of being saved that he
feared this might prove only another delusion. They could see him stand
there and put his hand to his head as he stared. It was so very
wonderful, this coming of a modern aeroplane to snatch him from his
living grave. And then that voice, how like the one he had never
expected to hear again!

But by degrees, as the little Bleriot monoplane sank lower, and the
forms could be more plainly seen, he began to grasp the truth. Again he
showed the most intense excitement, waving his arms and running to keep
up with them.

"Wait," said Frank, presently, as he saw that Andy was so excited he
could not carry on an intelligent conversation. "I'm going to speak with
him and find out if there's any clear spot where we can land."

"Uncle Philip!" he shouted presently, when Andy had subsided. "This is
Frank, your nephew, and Andy, your own son. Is there any clear place
where we can land?"

The aeronaut understood, because all this was right in line with the
profession which he had been following at the time of his vanishing from
mortal sight.

He indicated the quarter where a landing might be risked and upon
investigating by hovering over the same, Frank decided that it promised
success.

So the aeroplane dropped down and touched ground. It bumped along for a
little distance and then Andy, leaping out, managed to bring its
progress to a halt. They were in the enchanted valley, from whence those
wonderful messages had floated, one of which, by a strange freak of
fate, had eventually reached the boy thousands of miles away, for whose
eyes it had been intended!

And immediately Andy was clasped in the arms of his father. He knew him
despite the long gray beard, which had grown during his many months of
confinement, with hope daily choked by despair. His clothing was almost
in tatters, and he seemed thin and peaked; but the look upon his drawn
face now was of supreme happiness.

Then, after they had in some measure recovered from all this intense
excitement, the boys sat down to tell what a miracle had been wrought,
bringing the message to the home in far away Bloomsbury. With an arm
still encircling the form of his boy Professor Bird listened and asked
many eager questions.

"And to think," he said, finally, "that little messenger you saw going
up just now was constructed of the very last fragment of the old balloon
silk. I made a fire with flint and steel, filled it with hot air and
sent it up with prayers, believing that it was my forlorn chance. And
then I heard the exhaust of your motor. I feared my mind was giving way
under the terrible strain. When I looked up and saw an aeroplane sail
into view I fell down on my face, believing I had gone mad. But it was a
blessed reality, thank God!"

Plans were soon under discussion looking to leaving the valley as soon
as possible. About this time Andy happened to think of something and
began to fumble at his pocket.

"Oh, how I hoped and prayed when I bought that, father, that I might
have the happiness of seeing you smoke some of it," he said, as he drew
out a little packet of tobacco, on which the late prisoner pounced with
all the delight of an inveterate user of the weed, who had long been
deprived of a pleasure.

"I have been using dried leaves of a wild grape and some other things,"
he admitted; "but after all they were only vile substitutes. It was
thoughtful of you, my boy, to remember my weakness."

And Andy snuggled up close to him as he commenced to puff at his pipe,
using a match for the first time in many moons and smiling whimsically
when he struck the same, as memory played queer pranks within.

Meanwhile Frank wandered around to survey the scene of the professor's
imprisonment and figure how they were ever going to get out with the
aeroplane.




CHAPTER XXII.


RESCUED.

"What's the hurry?" asked Andy, when once they began to talk over their
plans for leaving the valley.

For once Frank agreed with his chum. They had plenty to eat along with
them and it might be just as well to wait for another day. By that time
all of them would have recovered to a great extent from the excitement
that had told upon them, particularly the professor, none too strong.

So it was finally concluded to stay right where they were until another
morning, when one at a time Frank would endeavor to convey them out of
the valley, not daring to risk two passengers at once with such a poor
field for the start.

The time passed quickly enough, for there were a thousand things to tell
on both sides. The aeronaut described his accident and related how he
had lived through all the dreary months that had gone. Fortunately there
did not happen to be any fierce wild beasts in the cliff bordered
valley, and while he had had adventures with venomous serpents, fortune
had stood by him.

He showed numerous little contrivances by means of which he had secured
game enough to supply his needs. There were nuts in abundance and some
wild fruits which, as a scholar, he knew the value of.

Water could be had in plenty, as a lovely stream flowed through the
valley, diving down at one end and vanishing in the rocks, to find an
outlet such as the human prisoner prayed for daily in vain.

Why, it was evening almost before Andy realized it, so quickly had the
hours sped along. How proudly had his father asked all about the
monoplane, which he examined with the most intense interest, knowing it
to have been mostly made by the two enterprising Bird boys.

Prom the way in which he smiled and nodded his head after this survey it
was evident that he was very well pleased with what they had done. And
he also made them tell all about that famous race through the air to the
hitherto unsealed crown of Old Thunder Top, which he remembered very
well.

"And now, let's think of having a jolly little meal," said Frank, as the
shadows began to lengthen down below the lofty cliffs, which was a
pretty good indication that night could not be far away.

"Count me in," said Andy, jumping up, for it was his duty to get busy
when the time came to make a fire and prepare a repast. "I guess we've
got coffee for a few times yet, and I smuggled a can of Boston baked
beans along when Frank wasn't looking, knowing that father used to be
right fond of 'em."

"Coffee! Beans! Why, you fairly take my breath away!" exclaimed the one
who for so many months had been deprived of all the comforts of
civilization and forced to sustain his life in the most primitive
manner.

When supper was cooking the professor made some excuse to wander
off. Frank knew, though, what ailed him.

"It's the aroma of that blessed coffee, that's what," he said to Andy,
who had looked a little troubled at this action on the part of his
father. "It's been so long since he's smelled it that it just makes him
wild. I know, because I had a little experience that way myself once,
only it was two weeks I had to go without when we were camping and not
many months. When supper's ready he'll come with a rush, mark me, Andy."

And he proved to be a true prophet, for no sooner had Andy lifted up his
voice to call that the meal was ready than the professor broke through
the bushes and hastened to take his place.

Frank lost not a second in filling a tin cup of the amber liquid and
handing it to the late prisoner of the valley.

He tasted and then nodded his head.

"Nectar for the gods, my boys!" he declared. "One never knows how
little things like this go to make up a portion of one's life until a
cruel fate has deprived him of them all. And to think I have a boy so
thoughtful as to fetch along a packet of smoking tobacco and a can of
the real Boston baked beans. Thank you, Frank, that's a heaping pannikin
you've given me, but I suspect I'm equal to the job."

They made a happy trio as they ate and chatted and laughed. Perhaps that
was the first hearty laugh Professor Bird had given utterance to since
the day he started in his ill-fated balloon from Colon on the Caribbean
coast to cross the Isthmus of Panama.

Before they went to sleep that night all preparations had been concluded
looking to getting out of the trap in the morning. Frank had made his
estimations and knew to a nicety just what his engine could do. Once
free from the valley he believed they could head direct for the distant
Magdalena, carrying two passengers and making short flights. It was true
that as yet he had never taken up any second passenger and it entailed
an additional tax upon the motor, but he had great faith in the little
Kinkaid engine and felt that it would respond nobly to any additional
demand made upon it.

But it would be advisable that he carry the professor out of the valley
and land him on that plateau where they had made their last halt, ere
going back for Andy. Then, from that elevated place they could start on
the return trip, with everything favorable for a successful flight.

The night passed at length, though it must have seemed interminable to
Andy. Frank knew that often his chum would rise up on his elbow and put
out a hand gently, just to touch the form of his sleeping father close
to him. And Frank did not wonder at it, for there were times when even
he found it difficult to realize that their remarkable mission had
actually proven successful.

At length the day came.

They were early astir, for much remained to be done. And there would
needs be deft manipulation of the gallant little monoplane by its clever
pilot, if two separate flights out of the enclosed valley were to be
undertaken.

Finally all was ready.

The professor had really next to nothing he wished to bring away. The
valley had grown hateful to him because of his enforced stay and he
never wanted to see it again.

He took his place in the seat usually occupied by Andy. His face was
grave, for he knew what risks they were running. But surely the lad who
had piloted the frail craft through so many perils would not fail now!

"Good-bye, both of you!" said Andy, beaming upon them, as he prepared to
assist in the launching. "Please don't forget me down here and let me
root, hog, or die for months. Birds of a feather flock together, you
know, so come back again, Frank."

Then came the start. It was anything but an easy job to get going in the
small space allowed by the character of the valley, but Frank had
figured it all out, measured the ground, removed such obstructions as
promised to give trouble and had perfect confidence in his ability to
make it.

And he did.

After that other ascent in the heart of the tropical forest he declared
he did not mean to let anything appal him henceforth.

Once they started circling the valley, low down and just missing the
tops of the trees growing there, Andy, sent vigorous whoops after them,
and his father answered by waving his hand, for hat he had none.

So, guided by the master hand of Frank Bird, the aeroplane rose above
the line of those hateful and cruel cliffs and for the first time since
his captivity the man of science saw the blessed outside world again.

There was no trouble landing him on the accommodating plateau, after
which the aeroplane started back for its second passenger.

Frank abated his vigilance not a particle. He knew that constant
watchfulness must be the price of safety when one is venturing to
imitate the birds and soar through the upper currents of the air.

Down into the valley he dropped, the monoplane behaving beautifully. And
presently he was shaking the hand of his chum again.

Once more was a start made. Frank breathed easier after it had proven a
success, for there were narrow escapes from a collision with some
obstacle, and he knew only too well what that stood for.

"Now we're all right, I guess!" sang out Andy, as they came out of the
depths and Frank turned the airship in the direction of the distant
plateau.

Naturally Andy was as happy as a lark, singing and calling as they
glided along, and finding scores of causes for attracting the attention
of his chum. Finally Frank had to caution him to slow down and not try
to make him look so much.

The trip was made in perfect safety. Indeed, Andy was now so confident
of the capacity of the monoplane, as well as the skill of its pilot,
that he expressed himself as ready to go anywhere in such a craft with
such a driver.

It required some planning to arrange matters so that both Andy and his
father could be carried at the same time; but Frank had been figuring on
this and fixed it in his mind.

Even after the start he felt more apprehensive than he allowed the
others to see, for this was after all an experiment. Aviators have gone
up with two passengers and in monoplanes, too, but the limit of their
stay aloft had never exceeded two hours, for the strain is very great.

So Frank hoped to find places where they might drop down to rest, thus
making the journey in easy stages.

He believed they had plenty of gasoline to see them through, for an
additional supply had been carried when starting from the neighborhood
of the boat.

But once they were afloat he realized that he had been borrowing
needless trouble, for the gallant little aircraft just acted beautifully
and seemed to be able to speed merrily along with two passengers almost
as well as with but one.

Of course there were many chances for trouble. There always are when
traveling in an aeroplane, since the least thing that goes wrong means a
descent or a fall.

Frank tried no lofty flight. He kept close above the tree tops, content
to make steady progress in the direction where his little compass told
him they would find the river.

Once away from the mountainous country and they were able to descend to
still lower levels, where the chilly air changed to hot, and there were
signs of life among the trees below--birds, monkeys and other natives of
the wilds showing themselves at times.

It must have been a glorious sensation to the old aeronaut to be thus
speeding along in a modern, up-to-date airship, after his enforced
idleness for so long. Again and again did he express himself in that
way, as he gazed over the expanse of country, and then allowed his eyes
to rest fondly on the form of his boy, more dear to his heart than ever
after what had happened.

"I think I see an open place beyond," remarked Frank, after they had
been moving something like two hours after leaving the high
plateau. "And it might be wise while we have the chance to go down and
look things over. Then we will feel fit for another spell of work."

Accordingly the aeroplane was headed downward. They circled the opening
once or twice in order that the pilot of the aircraft might get his
bearings perfectly, and then he headed for the ground.

Even as they were just approaching the earth Frank heard Andy give one
of his customary exclamations, such as announced an important discovery.

"Frank, there's the biplane in the opening!" was what he cried.

Yes, Frank himself had sighted it now, but the discovery came too late
to have any effect upon their movements, since they were bound to land,
not having room to rise again, even did they wish to do so.

And Frank, as he felt the wheels under the aeroplane touch the earth,
also heard a loud cry and some lusty Spanish expletives as a pistol was
discharged.




CHAPTER XXIII.


HOMEWARD BOUND--CONCLUSION.

As was his usual habit, Andy jumped before the monoplane had
stopped. Frank on his part had no sooner seen that everything was going
well than he snatched the Marlin rifle from its fastenings. He realized
that they were up against trouble of some sort, for those Spanish
exclamations told him there must be one revolutionist at least close by
ready to do battle.

"Frank, look out, he's got a pistol!" cried a voice, which he recognized
as belonging to Puss Carberry.

Just then he caught sight of a figure rushing forward. It was the same
man no doubt whom they had seen with Puss in the biplane. They had
evidently broken some important parts in landing and ever since must
have been busy trying to mend the same.

"Stop!"

When the advancing revolutionist heard this sharp command and saw that
he was being covered by a rifle in the hands of the determined looking
pilot of the monoplane, he sized up the situation and then raised his
hands in a way that meant he surrendered.

"Drop that gun then!" ordered Frank, and as he did so Puss seized upon
it with a snarl of joy.

"Now we'll see how two can play at that game, you skunk!" gritted the
other, as he snapped the pistol straight at the head of the man.

"Here, none of that, Puss. You leave him to us. He's our prisoner, not
yours!" ordered Frank, horrified at the rage which the other had shown.

So Puss found that he did not have any authority in the matter, and that
if he wanted to get assistance from his old-time rivals in order to
finish mending his airship and get away from so dangerous a locality he
must do what they said.

He told about how he and Sandy had been out for a trial spin two days
before. That was when Frank and his chum had sighted them from the
river. But that very night some of the revolutionists had made a descent
on the home of his uncle, who had a cocoa plantation not many miles away
from that of Mendoza, seized him and carried him away, as they also did
the little airship.

Threatened with dire things if he refused to obey, he had been compelled
to go up in company with the man who was now their prisoner, a Spaniard,
who had once sailed in a balloon and knew something about that type of
aviation, though having much to learn in connection with modern
aeroplanes.

Sighting our two Bird boys, of course Puss had known who they were. But
the man was positive that they must be spies sent out by the government
to learn what the revolutionists might be doing up the Magdalena. And he
had threatened all sorts of things, Puss declared, unless a hot pursuit
were carried on. Secretly Frank was of the opinion that it would
require very little urging to make Puss Carberry do his level best to
overtake any aerial craft piloted by one Frank Bird, toward whom he had
always felt the most bitter animosity.

After about an hour's hard work Frank managed to get the biplane in
decent trim for a flight. He was also able to spare the other some
gasoline.

Had he been allowed to have his own way Puss would have left the
Spaniard in the forest, where he might have died, being unable to make
his way to civilization. But Frank would not hear of it. He obtained a
solemn promise from the man that he would not make any further effort to
obtain control of the biplane, and then Puss was made to take him
aboard. Of course, Frank had made sure that the man carried no weapon
and that his revolver was thrown away.

They left the glade in the forest soon after the biplane had
started. Puss managed to keep close to the others while they headed off
toward the northeast. He did not wholly trust the passenger he was
carrying and wanted to remain within call of the three who relied upon
the monoplane to carry them to safety.

They could even shout out to each other as they sailed along. Thus Puss
warned them when they were approaching a camp of the revolutionists as
they drew near the region of the river, and they were able to change
their course, not wishing to again run the perilous gantlet of gun-fire.

When another descent was deemed necessary it was close to the Magdalena,
though many miles south of the town where the cocoa planters lived.

There was no reason why Puss should also descend, save that he wished to
be rid of his unwelcome passenger. The revolutionist might now make his
way to camp and electrify his fellows with a stirring account of his
various adventures. And one could easily guess that they would lose none
of their zest in the telling.

Puss did not expect to halt again when the monoplane was brought
down. He could make one flight of it now and reach the home of his
uncle, where doubtless Sandy was mourning him as lost.

Just as Frank had expected, Puss on saying good-bye tried to appear as
though something along the order of gratitude might be striving to gain
a foothold in his crooked nature.

"Say, Frank, I'm sorry now I ever tried to do you dirt," he observed, as
he held out his hand. "Let's forget the past and start all over again."

"Sure," replied Frank, as he readily took the offered hand; but it lay
like a cold toad in his grasp, as Andy afterward expressed it, for Puss
insisted on also bidding him good-bye ere he made a start in his
biplane.

"Well, now, what d'ye think of that?" said Andy, as they stood and
watched the other mount upward and caught the wave of his hand ere he
started down river, being fully five hundred feet high. "Did he mean it,
Frank? Would you really want to go so far as to trust that snake if the
chance ever came again for him to do you a bad turn?"

Frank shrugged his shoulders.

"Say, ask me something easy, won't you?" he remarked. "Because you know
how hard it is for a leopard to change its spots. Perhaps Puss _has_
seen a light; but excuse me if I doubt it. Naturally he felt kind of
cheap, because we got him out of a bad hole and placed him under
obligations. But that will wear off in a short time."

"Right it will," declared Andy. "I give you my word, Frank, that the
next time we see him he'll have a fine story all fixed about how he was
just going to jump on that Spanish revolutionary fellow, and twisting
his gun out of his hand, shoot him down, and then fly away. Oh, don't I
know Puss in Boots, though? He'll hate us both worse than ever just
because he's beholden to us. Rats! him reform? Not much!"

By the middle of the afternoon they had advanced far enough to know that
another lap ought to carry them to town, and of course all of them were
anxious to have the journey completed.

"If it could only be written up and sworn to," said Andy,
enthusiastically, "I reckon it'd go down in the annals of aeroplaning as
the most wonderful stunt carried out up to date. But people won't take
our word for it."

"We've got the evidence of it, though, in the person of your good dad,
and people may believe what Professor Bird says over his own honored
signature, however much they might doubt the yarn of a couple of boys,"
Frank remarked, as he took a last look, to see that both his passengers
were snugly settled, ere starting the motor.

"We're on the home stretch now!" declared Andy, after they had again
mounted up into the realm of space and found their course northward.

"Yes," observed Frank, "we're homing pigeons now, if any kind of bird."

"At any rate," laughed the professor, "we're birds of passage, and one
of them is mighty glad of the opportunity to get back into the old world
again."

In due time they sighted the town, and as before, the greatest
excitement followed as they headed across the place, looking to land
where the journey had begun--in the yard of the cocoa planter's place.

Of course Señor Carlos was delighted with the success of the
mission. For two days the Bird boys were the center of an enthusiastic
demonstration. Frank was a little nervous lest they be visited by some
of the revolutionists, but such did not turn out to be the case. And on
the third morning the little steam yacht once more headed down the
turbulent Magdalena, with a heavy rain promising more water to add to
the flood, as wet weather had seemingly set in again.

They met with no difficulties on the way down. Apparently the camp of
the revolutionists had been moved from its former position at the
narrows of the river. It might be those in charge had taken the alarm
and feared lest a government force must be on the way to capture them,
after being informed about the camp by the spies they had sent up the
river.

And Barranquila was finally reached, where they halted only long enough
to chat a short time with Señor José, who met them as before on the quay
and wanted to shake hands with the professor.

Knowing just how anxious the government was to get possession of
airships just then, Frank did not want to give them any further chance
to confiscate his neat little craft, under some pretense or other. So
they left the city at the mouth of the Magdalena and steamed away, bound
once more for Maracaibo, where they meant to take steamer for New York,
New Orleans or any port in the States.

The last glimpse they had of the river was the flood that was pouring
out between the jaws of land marking one of the mouths of the Magdalena
and making a distinct yellow area in the salty waters of the tropical
ocean.

The beloved little aeroplane had been safely boxed again and was making
the homeward voyage in their company. What strange and wonderful things
it had been through! Andy declared that they almost passed belief, and
he expressed his doubts as to their ever having an opportunity to pilot
that same aircraft through atmospheric seas as tempestuous as those they
had experienced in the tropics while rescuing the prisoner of the cliff
bordered valley. But then Andy was not gifted with second sight and he
could not foresee what the wonderful future might have in store for the
Bird boys.

They had by this time experienced enough of the fascinating new methods
of cruising in cloudland to want to continue. And it stands to reason
that other adventures would be lying in wait for lads so constituted.

For the present it must be enough to say they arrived safely at good old
Bloomsbury in due time and that the entire population was on hand to
greet the party when they stepped from the train. Also, the wonderful
little monoplane, the same that had been equal to the test in the race
for Old Thunder Top, had to be placed on public exhibition for several
days in the town hall, where every man, woman and child in all the
country around could examine and comment on the construction of the
airship that had brought fame and happiness to Frank and Andy Bird.

In due time Puss and Sandy turned up, minus their biplane, which the
government of Colombia had seized on some plausible pretext, though
paying liberally for the same. But they were soon at work constructing
another, which they claimed would far exceed the one that had been lost.

Professor Bird by slow degrees recovered his health that had been sadly
shattered by his experience down in that country. But he declared that
his days were over so far as aviation went, and that in the future he
must be content to take a back seat and see the honors of the family
carried off by the younger generation--the Bird boys.

THE END.