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Title: The Boy Aviators in Africa

Author: Captain Wilbur Lawton

Release Date: November, 2004 [EBook #6905]
[Yes, we are more than one year ahead of schedule]
[This file was first posted on February 10, 2003]

Edition: 10

Language: English

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*** START OF THE PROJECT GUTENBERG EBOOK THE BOY AVIATORS IN AFRICA ***




Produced by Sean Pobuda




THE BOY AVIATORS IN AFRICA

OR

AN AERIAL IVORY TRAIL

By Captain Wilbur Lawton





CHAPTER I

A REUNION


"Here, Harry, catch hold."

"Ouch--I dropped that cartridge box on my pet corn."

"Say, you fellows, are we going to Africa or are we on a Coney
Island picnic?"

"Be serious now, Billy Barnes, you may be all right as a reporter,
but as a shipping clerk you're no more good than a cold storage
egg."

"Well, I'm doing the best I can," was the indignant reply,
"here--I've got it all down: Box 10--  One waterproof tent, one
rubber-blanket, tent-pegs, ropes, more ropes.--Say, Frank, what in
the name of the 'London Times' and jumping horn-toads do you want so
much rope for?"

"To tie up a certain young reporter named William Barnes when he
gets too fresh," was the laughing reply.

The three boys sat about a heaped, confused collection of ammunition,
cooking-utensils, rifles, and camp "duffle" in general, one evening
late in May.  The eldest of the group, a sunny-faced, clear eyed lad
of about sixteen, held in his hand a notebook from which he called out
the inventory of the articles piled about him as his brother, a youth
of fourteen, sorted them out.  The third member of the trio was a
short, stocky chap of possibly seventeen, with sharp, blue eyes that
gleamed behind a pair of huge spectacles.  He was examining a camera
with care; from time to time turning his attention to an open notebook
that lay beside him in which he was supposed to be entering the list
as the other called it off.

The place where the boys were busying themselves was the upper floor
of a large garage in the rear of the Chester residence, on Madison
Avenue, New York City, which had been turned into a workshop for the
two young Chesters--Frank and Harry--already well known to our
readers as The Boy Aviators.  The well set-up lad who was so
industriously calling off the equipment that lay scattered about was
Frank Chester, and the ready classifier of the mixed-up outfit was
Harry, his younger brother.  The third member of the group was Billy
Barnes, the young reporter, already down to us as the chronicler of
the Chester boys' adventures in Nicaragua and the depths of the
Everglades of Florida.  Since the boys' return from Florida on the
U. S. torpedo boat, the Tarantula, they had been busy putting into
shape the rough working plans of the African hunting expedition they
had planned as a sort of vacation.

The ample bonus the government had awarded them for their singularly
clever work in rescuing Lieutenant Chapin, the inventor of
Chapinite, by their aeroplane Golden Eagle II, had supplied them
with ample funds for their trip.  As for Billy Barnes (or "Our
Special Staff Correspondent, William Barnes," as he was now known),
besides the sum realized from the sale of the rubies the boys found
in the Quesal Cave in Nicaragua, the money the youthful scribe had
made on writing up the boys' Florida adventures had provided him
with a good fat nest-egg.

The natural stimulus given to the red-blooded Chester boys by Mr.
Roosevelt's hunting adventures had a good deal to do, with their
resolution to go to Africa.  And now--after several weeks of work on
getting together as good an outfit as was procurable--they were
putting what Billy called "the finishing touches" on their
accoutrements.  Stacked in corners of the room were big chests
painted blue and marked with the boys' names and neatly numbered in
white painted characters.  These cases contained the different
sections of the Golden Eagle II, the aeroplane equipped with
wireless, that had made history in Florida.

There were twenty of these cases besides the ones labeled "Camp
Outfit," "Medical," "Armory Chest," "Grub Chest," and several
nondescript ones containing the odds and ends that an expedition of
the kind they planned would find indispensable.  In some smaller
boxes also were packed yards and yards of bright-colored cloth and
calico, spangles, cheap jewelry and brass ornaments for use among
the natives.  In making up their outfit the boys had taken the
advice of a well-known African traveler who had retired from his
adventurous life to purchase a place in New Jersey, where he
intended to spend his remain days.  Through a mutual friend the boys
obtained an introduction to him and his advice in selecting the
outfit had been simply invaluable.


"Go easy, carry lots of quinine, don't waste ammunition, and count
ten before you pick a quarrel with a native," had been his simply
laid-down rules for getting along in Africa, and these rules the
boys had determined to adhere to strictly.

"Say, is this going to be a hunting trip or an invasion of Africa?"
inquired Billy, quizzically as Harry sorted out and Frank read off
ceaselessly the apparently interminable inventory of the supplies of
the Chester party.  "I'm getting writer's cramp."

"A hunting party of course," laughed Frank, "but you know that
hunters who go into the bush depending on their rifles usually come
out a good deal thinner than when they went in.

"That's so," assented Billy, "but when we have a sixty-mile
aeroplane like the Golden Eagle II we can easily fly out to
civilization in case of necessity."

"Yes, if we have enough gasoline," assented Harry, "but how much can
we carry into the bush?"

"Just enough for our purposes and no more," replied Frank, readily,
"fortunately the soluble tablets of picric and glycerine will help
out our supply materially.  A few of these tablets dissolved in
gasoline render the efficiency of one ordinary gallon equal to
three; but I don't care to use them except in a case of absolute
necessity as they are very hard on an engine."

"Then we can count on every gallon we carry being of triple
efficiency?" asked Billy.

"Certainly," replied Frank, who had invented the tablets in
question, and which were an extremely useful addition to the
equipment of the modern aviator.  As the boys worked on and the
equipment, as it was classified, was packed away in the cases
assigned to each class of articles, there came a sharp knock at the
door of the garage building and a servant entered with a special
delivery letter to Frank.  The boy tore it open eagerly and then
gave a low whistle of astonishment.

"Read it out, Harry," he said, handing the missive to his brother.
"It concerns all of us."

Harry took it and read as follows:

DEAR FRANK AND HARRY:

Shall be in town to-morrow morning with my father and Mr. Luther
Barr, the well-known ivory importer.  He has a communication of
importance for you.  What it is I am afraid to trust to writing, but
you will know full details when you see us.  Will you call at the
Waldorf at ten-thirty and have breakfast?  We can discuss the matter
over the meal.  All I can say now is that if the Golden Eagle is
still in shape for her old-time stunts there is work ahead of her
that will prove harder than anything she has yet tackled.  However,
I know you are not the chaps to balk at a little danger--particularly
when exciting adventures are in the wind.

So long, then, till to-morrow:

                        "LATHROP EASLEY"

"Well, what do you know about that?" gasped Billy Barnes, here we
are fixing up for a nice little holiday trip to rest our shattered
nerves, and here comes, a job along that looks as if we should have
to work all summer."

"It certainly is curious," replied Frank musingly.

"What can Lathrop mean?  Who is Luther Barr?  I have heard the name
but I cannot place him."

"Lathrop says he is an ivory importer," suggested Harry.

"Easy to find out," said the resourceful Billy.  "Where's the 'phone
book?"

Frank handed the volume to him from its hook beside the instrument.

"Ah--here we are," exclaimed Billy, as he ran his finger triumphantly
down the "B" list.  "Barr, Luther--that's our man, eh?  Ivory
importer, offices No. 42 Wall Street--home, White Plains."

"White Plains, that's where Lathrop's folks live," exclaimed Harry.
"That's where he first became associated with the Golden Eagle."

"And turned out to be a good partner," added Frank.

"A jim dandy," agreed Billy.  "I tell you boys, I've got a good nose
for news and if there isn't some sort of a story back of Mr. Luther
Barr and Lathrop's letter I'll eat my hat without sauce."

Any acceptance of the young reporter's generous offer was interrupted
by a sudden noise in the usually quiet street.

"I tell you the fare's a dollar!" the boys heard an angry voice
declaim.

"'Tain't nothing of the kind or I'm a lubber--fifty cents is all
I'll pay.  I'll be horn-swoggled if you get a cent more, yer
deep-sea pirate," was the indignant phrased reply.

Something in the voice was strangely familiar but the "horn-swoggled"
settled it.

"Ben Stubbs," gasped all the, boys simultaneously and rushed out of
the garage to the street.

Here they found a stoutly-built, crisp-bearded man with a face
tanned to what Billy called a "weathered oak finish," arguing loudly
with a taxicab chauffeur.  The man was obdurate over his fare and
just at, the boys came on the scene was suggesting that his equally
determined passenger get back in the cab and take a ride to the
police station.

"The sergeant will settle our dispute," he said angrily.

"What's the trouble, Ben?" exclaimed Frank, giving the angry man on
the pavement a hearty slap on the back.

"Why, this here piratical craft," the other was beginning when
suddenly he dropped the battered bag he carried and burst into a
mighty roar--a regular Cape Horn hail.

"Back my topsails if it ain't you, Frank," he cried, wringing the
other's hands till the boy's arms were almost dislocated.  "And you
too, Harry, and keel haul me ef here ain't Billy too.  Well, if it
ain't good to see, you Chester boys again."

"Say, are you the Chester Boys--the Boy Aviators?" suddenly cut in
the chauffeur in a respectful tone.

"We are," replied Frank, "why?"

"Oh, well," said the chauffeur, "then I'll let your friend off with
fifty cents.  I thought he was a 'greeny'."

With that, he calmly twisted the dial of the cab which registered
$1.00 back to the fifty cent mark and coolly pocketed the coin the
indignant Ben handed.

"Does that thing work backwards?" demanded the amazed old
adventurer, as the taxi whizzed off before he could frame words to
express his indignation.

"Not often," replied Billy with a laugh.  "I guess that chap reads
the papers and thought it wouldn't do him any good to try to fool a
particular friend of the Boy Aviators."

"Well, boys, what are your plans?" demanded Ben, as--after the
rugged fellow had been introduced to Mrs. Chester, a sweet-faced old
lady, and Mr. Chester, a fine-looking, gray-haired man of about
fifty--he and the boys sat in the garage discussing the African
outfit.

"We hardly know now," replied Frank, and then in a few words he
described Lathrop's letter and its contents.

"Wherever that boy is there's bound to be doings," remarked Ben,
sententiously, when the young leader had finished.  "Down in Florida
when he wasn't tumbling into alligators' mouths or getting bit by
serpents he was allers up to some mischief--you mark my words
there's something in the wind now."

The boys talked late and long that night over the letter and what
possible plan Mr. Barr, the ivory importer, could have to discuss
that would be of interest to them, but they were able to arrive at
no definite conclusion except that there was nothing to be done
about it till morning.

As for Ben with his usual philosophic attitude toward mysteries, he
filled his pipe and silently smoked.  To those of our readers who
have not met Ben this phase of his character may seem inexplicable,
but to the boys Ben's passive acceptance of any situation had become
quite familiar.  Ever since they had rescued the rugged old
adventurer from a marooned treasure-mine in Nicaragua and he had
shared their strange adventures in Florida on the Chapin Rescue
Expedition, the old man had become as much a part of their necessary
equipment as the Golden Eagle itself.  He had arrived that night in
response to a telegraphed request to his cottage at Amityville on
Long Island, where he cultivated an extensive farm--also part of the
Quesal ruby profits--and devoted himself to fishing and hunting.

'The Boys' mere word, however, that they were off to Africa had been
sufficient to arouse the old man's roving instinct and here he was
on deck once more as active as a boy and almost as impatient for the
start for the Dark Continent.  Ben slept at the Chester's home that
night and if his dreams were not as populated with visions of
elephants, leopards, deer, huge snakes and pigmy savages as theirs
it was not any lack of interest in the coming expedition that was
responsible for it.




CHAPTER II

THE STOLEN IVORY


"Will you please send this card up to Mr. Beasley's rooms and tell
him that the visitors he was expecting are here?"

It was Frank Chester who spoke early the next day, as the boys, in
response to Lathrop's letter, stood at the Waldorf desk.  The clerk
looked at them a little disdainfully.  Frank and Harry Chester were
not the sort of boys who devoted much time to thinking about clothes
and while they both wore dark neat-fitting suits they certainly did
look a little out of place among the pasty-faced, cigarette-smoking
youths in loud-looking garments who constituted most of the young
men with whom the clerk was in the habit of coming in contact.

"I don't think that Mr. Beasley can see you now, call later," he
began, superciliously turning round to the letter-rack and sorting
out the mail and putting each guest's letters in the proper box.

For a second an angry flush rose to Frank's face.  The man's manner
was enough to irritate any high spirited boy.  But Frank Chester was
not given to what Bill Barnes called "flying off the handle."  He
calmly took another card from his pocket and in a rather sharp
voice, though his tones were even enough said:

"Are you going to send that card up at once or shall I call the room
on the telephone?"

The clerk faced quickly about.  The two youths he had looked upon as
rather awkward country bumpkins, judging as he did from their tanned
faces and broad shoulders, were evidently not to be trifled with.  He
glanced at the card as he rolled it up and handed it to a boy to be
placed in a pneumatic tube and shot up to the fourth floor, on which
Mr. Beasley and his party had taken rooms.

"Oh, you are the Chester boys?" he exclaimed with a strong accent on
the "the" and in markedly more respectful tones.

"We are," said Frank with a smile which was reflected on his
brother's face.

"I beg your pardon for keeping you waiting, I'm sure," said the
clerk with an apologetic leer, meant to be an engaging smile.

"That's all right," said Frank shortly, turning away from the desk.

"Well, having your name in the paper does do you some good after
all," remarked Harry with a laugh.  "That fellow certainly turned a
flip-flop, when he found out who we were."

Five minutes later the boys were ushered into the Beasley rooms and
were busily engaged shaking hands and exchanging all sorts of boyish
exclamations of welcome with Lathrop Beasley, a tall, rather slender
youth who had been their companion in Florida.  Like the boys,
Lathrop was an accomplished aviator and wireless operator, although
he had not the initiative or the sturdy pluck to perform the feats
that they had.  He was, however, a boy of considerable brain and
skill and among the boy-aviators of the country held an enviable
position.

"About your letter," began Frank when the first greetings were over.

"In a minute," replied Lathrop, "here's father now."

As he spoke, the portieres parted and a stout, fresh complexioned
gentleman, ruddy from his bath and shaving, appeared.  He had the
pompous manner of the successful man of business and seemed to the
Chester boys to be the least bit patronizing in his manner.

"Mr. Barr will be here in a minute," he said, after introductions
had been made by Lathrop, "he will explain to you his idea.  I am
merely a partner in the enterprise.  You will, of course, be glad to
accept any restrictions he may impose?"

"We hardly care to discuss that yet," said Frank, rather nettled by
Mr. Beasley's pompous manner, "until we know what he requires."  He
exchanged glances with Harry.

"In fact," he went on, "we were planning to take a complete rest and
follow in Mr. Roosevelt's foot-steps, by taking a hunting trip in
Africa, only," he added with a smile, "we meant to hunt by aeroplane."

"Wonderful," said Mr. Beasley, evidently much impressed by Frank's
ready manner, "when I was a boy, if a lad had a "bone-shaker"
bicycle he thought he was doing something fine, and as for flying--why,
we never thought of it."

"Perhaps the boys of to-day are further sighted," said Frank with
quiet note of sarcasm in his tone that was quite lost on the
well-meaning old merchant.  Indeed at that moment Mr. Beasley rose
heavily from his chair and stepped forward to greet a new arrival
who appeared from another room of the suite.

"This is Mr. Luther Barr, the famous ivory importer," he said, with
far more respect in his tones than he had used to the boys; whom
indeed, he looked upon as talented chaps, but still boys--which to
men of his caliber is an infallible sign that anything such youthful
persons may attempt is extremely likely to go wrong.  How erroneous
such an opinion is, those of our readers who have followed the
adventures of the Chester boys know.

Mr. Luther Barr deserves a new paragraph.  Long, lean and hollow
cheeked, the term "gangling" fits him better than any other.  Mr.
Luther Barr's black suit hung on him as baggily as the garments of a
cornfield scarecrow and Mr. Luther Barr's sharp features were not
improved by a small growth of gray hair; of the kind known as a
"goatee" that sprouted from his lower rip.  For the rest of the boys
noticed that Mr. Barr was gifted with a singularly gimlet-like pair
of steely blue eyes that seemed to bore through you.

"As sharp a man as ever drove up the price of ivory," added Mr.
Beasley as he introduced the boys to this singular figure, "he can
scent an ivory bargain--"

"From here to Africa," struck in Mr. Barr in a sharp nasal tone that
grated unpleasantly, "and you and I are going to be Kings of Wall
Street if these boys put this deal through for us," he added with
what was meant to be an amiable smile, but which, as a matter of
fact, distorted his face till it looked uncommonly like an old
Japanese war mask.  Indeed the boys, who had seen the collection in
the Metropolitan Museum, could not help smiling to themselves, as
the same thought struck each of them.

"Well, Beasley," exclaimed Barr suddenly, "I'm as sharp set as a
Long Island fox.  Let's have a bite of breakfast and then we can get
down to business."

From Mr. Barr's manner of dispatching his breakfast and the
remarkable skill with which he wielded his knife, in conveying
various morsels to his mouth, it was evident that he had spent so
much time piling up money that his social education had been sadly
neglected.  Once or twice the boys caught Lathrop's eye and they saw
that the lad was blushing with shame at the uncouth manners of his
father's friend. For this reason the boys refrained from paying any
apparent attention to Mr. Barr's actions, although--as, they
remarked afterwards--he was as well worth watching as the "sword
swallower in a circus side show."

"Yes, boys," said Mr. Barr with his mouth full of buttered toast and
ham and eggs, "I guess I know more about Africa than any man alive."

"You have crossed that continent?" asked Frank..

"No, sir," replied the old ivory merchant with some contempt.  "I
wouldn't waste my time where there ain't no ain't no money.  What I
mean is, I know more about the Gold Coast, the Ivory Coast and the
Slave Coast than any man in this or any other country and have got
more good solid coin out of them."

Mr. Beasley looked up admiringly from his plate.  Here was evidently
a man after his own heart.

"The Slave Coast?" echoed Harry inquiringly, "I thought--"

"Thought there wasn't no more slaves, eh?" inquired Mr. Barr
amiably, swallowing his coffee with a noise like water running out
of a bath tub, "wall, that's because yer young.  When yer git older
you'll larn that there's money in everything here's a demand for,
and there's just as big a demand for slaves on some rubber
plantations I could tell yer of as there ever was in the old days of
the South--and more money in 'em on account of its being more
dangerouser."

"Do you mean to say that there is slave-running now?" asked Mr.
Beasley, while both Frank and Harry wondered and Lathrop looked
uncomfortable.

"Sure I do," chirped Mr. Barr, "but no more for me.  There's too
many British gunboats and 'Merican gunboats and Dutch gunboats and
what not about now to make it comfortable or healthy.  No, I've
retired from that business--but there's money in it," he concluded
with a regretful sigh.

Immediately Mr. Barr had concluded his breakfast--and with his
apparently slim accommodations it was a wonder to the boys where he
put it all--he snapped, with a flinty glint of his small pig-like
eyes:

"Now, let's git down to business.  You boys want ter make a bit of
money?"

"'To be sure we do," replied Frank, "but we don't want to make any
that isn't honest money."

"We'll, there's no accounting for boys nowadays," sighed Mr. Barr,
"however, you needn't worry about this money--there'll be plenty of
it and it'll all be good honest coin."

"What do you wish us to do?" demanded Frank.

"Just this: Mr. Beasley here and me is in on a deal in ivory.  That
is, we were, but the big cache we had hoarded up in the Kuroworo
Mountains in the Bambara country has been stolen by a rival trader,
an Arab named Muley-Hassan.  We know where he's hidden it and we
know, too, that he won't dare to bring it out till he thinks that we
aren't watching him.  Now the time is ripe for a big deal in Ivory.
There is a shortage in the market.  Prices will go up sky high.  If
we get it out in time we'll make a barrel of coin, but if we don't
we stand to lose heavily."

Mr. Beasley gave a groan; to the boys' amazement he seemed to be
about to collapse.  Lathrop too looked ill and anxious.  Old Barr
paid no attention, however, but went on.

"Now, I heard about you boys and your air-ship, and I heard, too,
that you was planning a little trip to Africa and thought you might
like to combine business and pleasure."

He drew from his pocket a much-thumbed, crudely drawn map and spread
it out on the table.  How he obtained it, the boys never learned
exactly, but they heard later that a treacherous attendant of the
ivory dealer had sold it to him for a good round sum.

"This country down here," he said, indicating it with a black rimmed
finger nail, "is the Southern Soudan.  Here's the Bambara country to
the north of Uasule.  Now right at this point, in the Moon Mountain
range,"--he pointed to a red-marked trail zigzagging across the map
to the range and terminating in a red star--"right at that thar
point, old Muley-Hassan, the Arab, has hidden our ivory cache.  You
see the latitude and longitude is marked and furthermore--and here's
the most remarkable part of it--you will know the spot when you see
it by the fact that the mountains above the cache present an exact
facsimile of an upturned human face.  In a direct line drawn from
the nose of this face, where you see the red star, lies the ivory."

The boys were deeply interested.  Unpleasant as was the impression
old Barr had made on them, yet what he was disclosing was
impressive; but as yet they did not show that they were anything
more than casually struck by it.

"Well, Mr. Barr?" said Frank, as the old matt paused impressively.

"Well--" said Mr. Barr, "the scoundrel stole it and it's up to you
to get it out of there, if you will undertake it."

"How does it depend on us?" asked Frank.

"In just this way.  Muley-Hassan has his eye on us---we can do
nothing toward locating the ivory.  You can pitch a camp there and
scout about for it in your aeroplane or dirigible or whatever you
call it."

"But even if we do find the Arab's hiding-place, what good does that
do?" objected Frank.

"We can arrange with the French government to send soldiers up into
the country and get the stuff out, if necessary," readily replied
the wrinkled old ivory dealer, "but we can make no move till the
cave is located.  If they suspected we were after it, they would
soon move it to another hiding-place or even pack it cross-country
to the Nile and ship it out by the Mediterranean."

Frank and Harry asked leave to hold a brief consultation at the
conclusion of which, they announced that they would think the matter
over, and see Mr. Barr at his office the next day.  The old man was
far too shrewd to insist on a decision then and there, and so he
left the hotel with the boys' promise to consider the matter
carefully.  As for Frank and Harry, they had pretty well made up
their minds not to have anything to do with Mr. Barr, but an
unforeseen circumstance altered their determination.  As Barr left
the room with Mr. Beasley, Lathrop turned on them with troubled
eyes.

"Will you do it, Frank?" he asked anxiously.  "Please say yes."

"Why, Lathrop, whatever is the matter," asked Harry, noticing the
almost painful anxiety, with which the boy looked at Frank and hung
on his decision.

"It's just this," said the boy in a voice that shook, as he tried to
steady it, "if that ivory isn't found, we shall be ruined.  My
father will be beggared."

"Beggared," exclaimed both the Boy Aviators who had regarded Mr.
Beasley--as indeed did his friends in general--as one of the "best
fixed" business men in New York.

"It's true,"' said Lathrop, despairingly.  "He has been speculating
foolishly and entered into an agreement with this man Barr to borrow
money for still further stock deals.  The only hope he has of paying
his debts is the realization of the profits he could have made on
the ivory.  Its theft was a bitter blow to him, not so much for his
own sake, as for my mother and sisters.  Myself I don't care, I can
get out and work, but it would break my heart to see them reduced to
poverty."

The situation was a difficult one for the Chester Boys.  They had
taken a hearty dislike to the crafty old ivory merchant and had made
up their minds not to enter into any enterprise in which he was
interested.  Here, however, was a new complication.

"Give us half-an-hour, Lathrop," said Frank at length, and the two
boys withdrew to another room to talk the matter over.  It was ten
minutes past the agreed time when they came back.

In the meantime Lathrop had been joined by his father and the two
had waited in painful anticipation for the Boy Aviators' verdict.

"Well--," began Lathrop eagerly as the two boys with grave faces
reentered the room.

"Well," said Frank, with a smile, "I guess we'll help you out,
Lath."

Tears stood in the eyes of both Mr. Beasley and his son, as in shaky
voices they endeavored to thank the Chester Boys.

"That's all right, Lathrop," said Frank at length--"turn about's
fair play.  You drove the aeroplane to Bellman's island you remember
and saved us--now, we'll save you and your father, if we can--how
long can you give us, Mr. Beasley?" he asked, briskly turning to the
thoroughly humbled merchant.

"Eight weeks--if I hear from you by cable in eight weeks I can keep
things going," was the reply.

"Phew!" whistled Frank, "that's not an awful lot of time."

"Can you do it, Frank?" asked Lathrop eagerly.

"We'll try as hard as we know how," was the modest answer.

"And--and you'll take me along?" faltered Lathrop.

"Sure, you can come as your father's representative at large,"
laughed Frank.




CHAPTER III

THE DARK CONTINENT


About a month after the events related in the last chapter the
bluff-bowed French coasting steamer, Admiral Dupont, dropped anchor
in the shallow roadstead off the steamy harbor of Fort Assini on the
far-famed Ivory Coast.  A few days before, the boys had left Sierra
Leone and engaged quarters on the cockroach-infested little craft
for the voyage down the coast.  It was blisteringly hot and from off
the shore there was borne on the wind the peculiar smell that every
traveler knows as "African."  It is the essence of the dark
continent.  Our young voyagers and Ben sniffed at it eagerly.

"Smells like marigolds," said Billy at last--and it did.

But there was soon plenty more to discuss than the strange
appearance of the town, which in reality was little more than a big
village with here and there one, or two houses of some pretension
scattered about.  For the rest, it consisted of the wickerwork huts
of the natives.  Back of the town were dense forests and beyond
these again a long blue line of hills.  An unhealthful looking lagoon
lay between the houses and the mainland, into which the boys had been
told the Bia River, up which they were to begin their voyage to the
interior, emptied.

A broad yellow beach stretched in front of the houses and from this,
as soon as the little steamer dropped anchor, whaleboats and canoes
in great numbers were launched through what looked to be a thunderous
surf.  They were navigated by Kroomen--or Krooboys as they are
sometimes called--and who are a superior race to most of the natives
of Africa.

Some of the paddlers and oarsmen in the boats that surrounded the
Admiral Dupont were almost six feet in height and splendidly built.

"Good looking fellows those," said the captain, who had joined the
group of wondering young adventurers, "but in spite of their good
looks they are petty thieves, if they get the chance."

Of this quality, the boys were soon to get an example.  Frank had
laid down his field-glasses on a deck chair and didn't give them any
more thought, even when the decks were fairly swarming with
half-naked, chattering, laughing Kroomen.  When he looked around for
them, however, for the purpose of making out more clearly the
outline of the distant mountains, the glasses had vanished.

The young leader quickly divined what had occurred and stepping to
the rail he held above his head an English sovereign and a pair of
glasses, borrowed, from Billy.

"I'll give this money to the man who finds my field glasses," he
shouted.

"It's a long chance," he remarked to Harry, "there may be some one
there who understands English.  Anyway they can see that I'm willing
to give money for something like the object I held up."

As much to Frank's astonishment as anyone else the next minute they
heard a hail from a canoe containing two particularly black Kroomen.

"Hey, boss;" one of them was shouting, "what you lost, eh?"

"Some one stole my field-glasses," shouted back Frank.

"All right, American massa," hailed back the Krooman, "I sail long
time 'Merican ships.  I catch him for you."

"Well, what do you think of that?" demanded Billy.  "If the Statue
of Liberty had come off her perch and done a song and dance you
couldn't have astonished me more than to hear that sack of coal talk
English."

"They take several of those fellows to sea on trading ships, that
stop in here for logs from the interior," struck in Ben.  "It
wouldn't surprise me but what that fellow there has been in New York
harbor, yes, and in San Francisco too."

The boys looked their astonishment.

"They are good hard workers," went on Ben, "and make good sailormen.
They always come back here though in the end.  They are as home
loving as a house cat."'

While the boys talked, their baggage was being hoisted into a
lighter that lay alongside, ready for shipment ashore.  They were
about ready to quit the ship when their attention was attracted by a
terrific uproar among the natives alongside.  Two or three canoes
had been upset and in the water half a dozen Kroomen were splashing
about like big, black fish.

"They'll drown," gasped Harry, as he watched the furious water
battle.

"Not them," sniffed Ben, "they are as much at home in the water as
they are ashore.  Hello!" he exclaimed, suddenly pointing, "there's
your field-glasses again, Frank."

Sure enough, from the hands of a spluttering, half-drowned native,
the Krooman who spoke English had just wrested a dripping pair of
black morocco-covered field-glasses.  He held them aloft in triumph,
treading water while he held the other's head under the sea as a
punishment for his thievery.

"I catch 'um, boss, I catch um," he kept shouting triumphantly.  A
few seconds later, having half drowned the unfortunate thief, he
stood dripping like a figure cut out of black basalt before the boy.
As he received his recovered property Frank presented its rescuer
with the sovereign.  If it had been a fortune the man could not have
been more overcome with gratitude.  He sank on his knees.

"You come ashore my boat?" he begged.  "Cost nothing to United
States boys."

The adventurers assented and, having seen their baggage properly
stowed on the lighter, they landed through the surf a short time
later and found themselves on the flat, yellow beach facing the
rather dreary  looking row of Europeans' houses.  The method of
landing the surf boats and the wonderful dexterity with which the
natives handle them is worth a whole chapter to itself.  But it
might prove tedious reading, so suffice it to say, that with one man
standing erect in the stern with a steering oar, and the others
paddling like demons, the Ivory Coast boatmen invariably land their
passengers, in a smother of foam which seems overwhelming, without
spilling a drop of water on them.  Not a visitor to this coast but
has been impressed by their wonderful skill.

"Well, here we are," remarked Billy, looking about him at the novel
surroundings.

"The first thing to do," announced Frank, "is to go to the house of
Monsieur Desplaines, to whom Mr. Barr gave us a letter of introduction,
and talk over our plans."

Monsieur Desplaines was the consular agent of the United States
government at Assini, which is a French port, and had promised by
cable to Mr. Barr to give, the young travelers all the advice that
his experiences could suggest.  He had also volunteered to select
for them a train of native baggage carriers, and hunters that would
be reliable.  There are no roads into the heart of Africa and
everything is transported by human pack-trains.  The natives of this
part of the coast are strong, muscular men not easily fatigued and
are capable of carrying burdens on their heads twenty-five miles or
more a day without exhaustion.

As the boys started to make their way up the beach a trim figure
with neatly waxed black mustaches, almost extinguished in a huge
pith helmet and dressed in white duck with a red sash about the
waist, emerged from the nearest house and hastened toward them.

"Welcome to Africa!" cried the newcomer as he approached and who, as
Frank at once guessed, was M. Desplaines himself.  "Come with me to
the house and make yourselves at home."

The boys shook hands warmly with the little Frenchman who seemed so
hospitably inclined and followed him eagerly toward the whitewashed
house from which be had emerged.

"I would have been at the steamer to meet you," he exclaimed
apologetically; "but she got here a day ahead of time and I was not
prepared."

Inside the house, which was delightfully cool and darkened by
jalousies from the glaring heat outside, the young adventurers were
introduced to Madame Desplaines and two little girls, who
constituted the family of the consular agent, who also kept the
general supply store at Assini.

After dinner that evening, M. Desplaines talked long and earnestly
to the boys.  Of the real object of their mission, he had of course
no knowledge.  That was kept a secret even from Barr's intimates.
There was too much at stake to let it leak out.  His idea was the
boys had come on a hunting and exploration, much of which was to be
performed by aeroplane.  He informed the boys that, acting on cabled
instructions, he had laid in a good supply of gasoline by the last
steamer from Sierra Leone and that arrangements for a train of
carriers and for boats up the river had been made.  There was a
wheezy steam launch belonging to the trading post which would tow
the boats up the Bia River as far as they desired.  The Kroomen the
boys engaged would take them to that point would then be abandoned,
as they refused to go far from the coast.  Such was the outline of
M. Desplaines' conversation with the travelers.

The evening was far advanced when already the little party was ready
for bed and already their imaginations had been fired by the tales
that the consular agent had told them of the interior of the wild
Bambara country.  As they were saying good night to their hospitable
host and hostess, there was a knock at the door.  In response to M.
Desplaines shouted: "Come in," a tall coal-black figure stalked into
the lamp-light.  The glow shone warmly on his black skin and lit up
the mighty muscles that played beneath it.  The strength of the man
was evidently tremendous.  The boys, to their surprise, recognized
him at once, as the rescuer of Frank's opera-glasses.  He paid no
attention to Desplaines or his family, but walked straight up to
Frank.

"Hi boss, you go hunt, you go far into land of Bambara," he said,
raising his mighty arm and pointing to the northeast.

Frank nodded.

It was a strange scene.  The boys and Ben in their hunting costumes
and stout boots, M. Desplaines, short and inclined to be fat and as
neatly barbered and tailored as if he had just stepped off the
boulevards, Madame Desplaines and her little girls in cool, white
frocks--and in the center of the group--dominating it by his
impressive manner and mighty form--the huge, ebony Krooman.

"In the land of Bambara much game," went on the Krooman.

"So we have heard," replied Frank.

"In the land of Bambara much danger," continued the Krooman, fixing
his dark eyes full on Frank, "much danger to the white boys, who fly
like birds."

"Why, how do you know that?" exclaimed Frank, amazed that the
Krooman should not only know their destination--which might have
been a guess--but have divined the fact that they had an aeroplane.

"Krooman know much that white man not know!" replied the giant
black.

Then, rising his finger, he counted the amazed group of adventurers
who stood transfixed at the scene.

"One--two--three--four--five go to Bambara," he intoned.  "Come back
one--two--three.  Two die.  Sikaso, know."

Before any of the astounded party could frame a question or open
their lips, the huge figure had stalked to the doorway and vanished.

"He'd make a nice, comfortable house-pet that fellow," said Billy,
who was the first to speak.  "One, two, three, four, five go to
Bambara," he mimicked.  "Come back one, two, three.  Two die.
Sikaso know.  Br-r-r-r-r, he gives me the creeps."

They all laughed at Billy's absurd aping of the stately negro, but
nevertheless none of them felt inclined for more talk that night.
Somehow, the Krooman had cast a gloom on the party.  Had they known
how nearly his prophecy was to come to fulfillment they might even
have been tempted to abandon the expedition.





CHAPTER IV

THE WITCH-DOCTOR


Bright and early the next day Frank and Harry were up and stirring,
and the other members of the party were not long in joining them.
The almost innumerable packing cases and chests containing the
duffle, ammunition, armament and the sections of the Golden Eagle
were scattered about the little "compound" or garden of M.
Desplaines' residence, having been brought ashore overnight by a
crew of Kroomen.  M. Desplaines appeared while the boys were still
contemplating their outfit and wondering if it would be possible to
accommodate it all in the little flotilla which, it had been
arranged previously, was to take them up the river to the camping
place from which they were to strike out for the Ivory Mountain.

"I really almost envy your trip," he said, "although it will be
fraught with danger.  Still you go well armed and provisioned, and
from what I have heard of you, you are not the sort of boys to let a
few obstacles upset you."

While they were still talking and waiting for breakfast to be
announced they were joined by a singular figure.  It was that of a
white man in rather shabby ducks and crowned, as was M. Desplaines,
with a huge, white pith helmet.  Over one shoulder he carried a
green butterfly net and under one arm he had tucked a tin box.
Round his waist was a leather belt from which hung, in addition to a
revolver and cartridges, a glass bottle with a wide stopper with a
chloroformed sponge reposing in the bottom.  It did not need the
introduction of the newcomer by M. Desplaines as Professor Ajax
Wiseman, to tell the boys that Dr. Wiseman was a naturalist.

"My dear professor, what are you doing here?" exclaimed M.
Desplaines as soon as the introductions were over.

"I arrived this morning from Grand Bassam on a coasting schooner,"
replied the professor, carefully setting down his tin box.  "I have
a remarkable specimen of the Gladiolus Gorgeosi in there," he
remarked importantly.  "I am contemplating a trip into the interior
via the Bia River and came to you to see if you could arrange
transportation."

M. Desplaines looked at the boys.

"These young men have engaged the steam launch, to tow their
expedition up the river," he said hesitatingly; "they are going on a
hunting trip, into the interior, and have, I venture to say, one of
the most complete outfits I have ever seen."

The naturalist looked wistfully at Frank.

"I suppose there would not be the least objection to my availing
myself of your assistance in getting up the river," he said,
blinking behind his spectacles like an old bat who has unexpectedly
emerged into the sunlight.  "I have only two canoes and as I carry
my own attendant I shall be no trouble."

"We shall be delighted to accommodate you," rejoined Frank heartily,
"but I shall have to place one restriction on you.  When we reach
our destination we must part company as we have work to do of a
confidential nature.  Our employer, Mr. Barr--"

"Old Luther Barr," burst out Professor Wiseman suddenly.

"Why, yes," rejoined Frank, rather taken aback, "you know him then?"

"I--I have heard of him," replied the other with a slight hesitancy
which was, however, so faint as to be hardly noticeable.  The voice
of Madame Desplaines summoning them to breakfast broke off any
opportunity for further questions on a matter that plainly, for some
strange reason or other, seemed to have heartily interested--even
disturbed--the naturalist.  Frank felt troubled for a moment at the
idea of having let Professor Wiseman form a portion of their party
even for a short distance.  But he dismissed the idea almost
instantly.  The queer expression that passed over Professor
Wiseman's face at the mention of the ivory trader's name might have
simply been due to astonishment at hearing it again.  Still Frank
decided to keep an eye on Professor Wiseman.

The conversation at breakfast naturally enough dealt with the little
known country the boys were to penetrate.  Then it was for the first
time that they heard mention of the mysterious tribe of the Flying
Men who were reported to be equipped with rudimentary wings--like
those of an undeveloped bat with which they managed to flit from
tree top to tree top like true flyers.

"Oh, come," laughed Billy, "I've heard of tailed men and white
Africans with red top-knots like Lathrop, but a race of winged men
is coming it too strong."

"Laugh if you like," declared Professor Wiseman who had brought up
the subject, "but some time ago I articulated a skeleton brought me
by an Arab slave trader and found extending from the shoulder blade
two distinct bony frames which had in life apparently been covered
with a thin fleshy substance of leathery like tenacity stretching
thence to the wrists.  I asked the slave trader where he had found
the skeleton," went on the savant, "and he told me he had come
across it at the foot of a giant silk cotton tree in the Bambara
country."

The boys exchanged glances.  It was to the Bambara country--the
country of the legendary Flying Men--that they were bound.

"Is any more known of this tribe?" inquired Frank.

"Very little except what you can pick up from the natives, which is
little enough," replied Professor Wiseman, "they seem to have a
dislike to speaking of the Flying Men--to whites at any rate.  I
think, too, they fear them.  Report has it that they live in
cave-like holes in the side of a giant, black basalt cliff reached
by a subterranean river.  They reach the ground by taking short
flights from the holes they live in and regain the cliff dwellings
by means of rope ladders formed of twisted creepers."

"Then they cannot fly upward?" asked Frank.

"It would seem not," replied the naturalist, "their wings only serve
as gliders.  Possibly once in the remote ages they could fly as well
as great birds but with the course of the ages and disuse their
wings have dwindled."

As may, be imagined the idea that within a short time they were to
be in the country of the mysterious tribe caused a tremendous stir
among the boys and when after breakfast their strange friend of the
night before, Sikaso, appeared they at once overwhelmed him with
questions.  But strangely enough Sikaso made no reply to their eager
queries.

He shook his great bead and seemed to be embarrassed, if not by fear
at any rate by reticence.

"In Misoto Mountains many strange Ju-jus (fetishes)," he said in an
awed tone, "Misoto Mountains no good for white boys--white boys stay
away."

"Not much," chimed in Harry, "that's just where we are going."

"You go Misoto Mountain," said the giant black in an astonished
tone.

"That's what we are," exclaimed Lathrop.

The black gazed at the ground and drew a small circle on the dust
with his toe.  In the center of it he made a cross.

"That my dukkeri (fate)," he said slowly, "you go, Sikaso he go too.
I see it in the smoke."

"Saw it in the smoke?" repeated the amazed boys.

"In smoke of Ju-ju fire I see it written.  I see five go, three come
back, in smoke too.  I have spoken."

He stalked off as I suddenly as he had the night before and left the
boys to gaze in a bewildered way after his huge figure as it swung
down the road.

"That fellow's the best disappearer I ever saw," said Billy Barnes
at length.

"I wish he'd stop that stuff about 'five go three come back,"' said
Lathrop, "it gets on your nerves."

"What could he have meant by seeing it in the smoke?" asked Harry
bewilderedly.

"Just this," broke in a quiet voice behind them.  It was Professor
Wiseman, who had glided up to them as silently as a cat.  "It is a
common trick among the witch doctors--of whom our friend yonder
seems to be one--to divine events by means of the smoke from a fire
built to the accompaniment of special incantations."

"Well, that's cheerful," commented Billy, "but tell us, Professor,
how often do they hit it right?"

"Nine times out of ten, young man," said Professor Wiseman
impressively fixing Billy with his gaze just as he would have
impaled a bug or grasshopper, "and the tenth time they come so near
the truth as to be uncomfortable."

"I have heard of such things, but I always put them down as
impossibilities," gasped Frank.

"Just travelers' tales," said Billy.

"There are many things for the young to learn in Africa," remarked
Professor Wiseman coldly and gazing at Billy with squashing
intentness; "the young do not believe many things merely because
they are young--and foolish."

"Gee! that was a nailer for fair," said Billy afterward.  "I felt as
if the Doc was running a big blue pin through me and sticking me on
a bit of cork,"

That morning, as the start for the interior was not to be made till
the next day, M. Desplaines asked the boys if they would care to try
a little fishing at the foot of the famous Jumbari Falls which lay
on a branch of the Bari river a short distance from the town.  Of
course the boys assented eagerly, but as it was found that only
Frank and Harry were expert canoeists, it was agreed that the others
should fish from the bank while the two young leaders trolled their
lines from a native built craft.  This canoe was kept at the falls--to
which they tramped the two miles overland by a narrow trail.

The falls were a magnificent sight.  From a dark red rock, fully two
hundred feet in height, a great volume of water poured its roaring
current into a boiling pool below.  The cliffs shot up sheer on all
sides and were covered at the bottom with luxuriant green growth
like seaweed, while higher up, ferns, as big as rose-bushes at home,
and trees of a hundred varieties clung wherever they could find a
root-hold.  As the party arrived at the top of the ravine and gazed
down, the uproar of the water was so terrific as to render any
speech inaudible.  M. Desplaines, who led the party, pointed to a
hole in the rocks and a second later vanished into it.

At first, consternation seized on the boys who thought that an
accident had happened, but seeing not hearing Professor Wiseman's
reassuring laugh and noticing him plunge after M. Desplaines, the
boys rightly concluded that the aperture was a subterranean entrance
to the foot of the falls.  And so it proved.  A steep flight of
steps was cut in a deep cleft of the cliff down to the water's edge.
A few minutes after they had begun the descent, the little party stood
on the brink of the whirling pool into which the mighty falls roared
their thousands of tons of water.  Following M. Desplaines, they
advanced down the stream to a  point where a bend shut off like a
rock curtain the deafening uproar of the cascade.  Here a canoe lay
moored and Frank and Harry stepped into it and shoved off.  Their
lines and other equipment they had in their pockets.

As they shoved out M. Desplaines shouted something that they did not
catch and pointed down the stream.  How near the fact that they
could not hear his words was to come to costing them their lives
neither of the boys guessed.




CHAPTER V

THE POOL OF DEATH


"Say, Frank, have you noticed that we are going to have a hard
paddle back against this current?"

The boys had been fishing about an hour when Harry spoke.  So
engrossed had they both been pulling in fish of a dozen strange
varieties and brilliant hues that neither of the lads had noticed
that the canoe had drifted down stream far from the starting point
and that in fact when they looked up they were in an entirely
strange part of the river.

"You are right, Harry," rejoined Frank, as he looked up at the steep
banks on either side of them, "we have drifted a considerable
distance.  Come on, out with the paddles and we'll be getting back."

But it was one thing to talk of getting back and quite another thing
to do it.  The boys, after an hour of paddling, were dismayed to
find that although their arms ached with the exertion and they were
dripping with perspiration, they had made hardly any progress
against the current.

"It's too much for us," gasped Frank.

"What on earth are we going to do?" asked Harry with blanched
cheeks.

Frank glanced at the shore on either side.  For a minute he had
entertained a thought of landing and walking back along the beach.
But there was no beach.

The river boiled along between narrow walls which shot sheer up from
the water.  There was not even a niche in their smooth surface to
afford a foothold to a mountain goat.  They were caught in a trap.

The only thing to do was to drift down the river and trust to luck
to find a landing-place.  In their extremity they shouted at the top
of their voices to let their comrades know of their plight, but
their cries were unanswered and they began to wish that they had
saved their breath to use in the task of keeping the canoe steady in
the current.

While they had been pondering their situation, moreover, they had
been swept with almost incredible rapidity down the river.  The
walls here grew narrower and narrower and the water fairly boiled in
its narrow confines.  Its dark surface was flecked with white foam,
and to make matters worse, as the walls closed in the light became
fainter, till the boys were being carried downward through almost
subterranean darkness.

In the intense gloom their white strained faces shone out like
pallid beacon-lights.

"Hold her steady," said Frank in a tense voice as the canoe wobbled
crazily in the swollen current.

"I'm doing the best I can," gasped out poor Harry desperately plying
his paddle.

It the canoe was to get broadside onto the current, even for the
fraction of a second, Frank well knew that nothing could save them.
It was a terrible situation.

Helplessly they were being borne at dizzy speed to what seemed
almost certain death--for certain it was that they could not hold
out much longer.  Already their overstrained muscles were only
mechanically doing their duty, but before long Frank realized that
even his-well-trained young body must collapse--and then, what?

Suddenly there was borne to their ears a sound that made both boys
chill with terror.

It was a mighty roaring like the furious boiling of some giant
kettle.  A thousand shouting voices seemed blended into one to form
the music, of this ominous orchestra.  Louder the noise grew and
louder, as the pass through which the river now tore like a runaway
race-horse grew narrower and blacker.

What could the awful uproar mean?

They had not long to wait before the truth burst upon them.  They
were nearing, at what seemed express speed, a whirling, roaring mass
of waters that shouted at them like some animal calling for its
prey.  The boys' cheeks blanched as they realized that nothing but a
miracle could save them from being sucked into this watery abyss.

Desperately they plied their paddles but if they had been useless
further up the stream they were doubly inefficient now.  If they had
stroked against the rushing current with feathers they could not
have had less effect in checking the death rush of the canoe, which
was tossed along on the racing tide like a chip of wood.

Suddenly the canoe was struck a terrific blow.

Before either boy could realize what had happened they were both
struggling in the water.  So dazed were they by the mishap that it
was several minutes before they understood that they were clinging
to the to the trunk of some huge tree.  It was this trunk that had
wrecked the canoe and thrown them overboard.

In reality, though, they were little better off now than they had
been while the canoe was being whirled down the river.  It looked as
if they had been saved from one death only to face a worse.  With
all their might they clung side by side.  Dripping wet, half-blinded
and bruised by the battering they got as the trunk smashed from side
to side of the narrow passage, the indomitable American pluck of the
two lads yet held good in this extremity.

"Is it good-by, Frank?" Harry found strength to murmur.

"While there's life there's hope," came Frank's brave reply in his
favorite axiom.  "We'll live to fly the old Golden Eagle yet, let's
hope."

There was no time for further talk, even had the boys been in any
position to consider conversation.  The trunk was rapidly nearing
the whirlpool--and death.

Small wonder that brave as the boys were a despairing cry burst from
their throats as they saw what seemed the end of their ride close
upon them.  It was as if they could feel the breath of the Pale
Horseman already blowing chilly in their faces.

But suddenly a strange thing happened.

Both boys had closed their eyes and only moved their lips in prayer
as they saw that inevitably in a few minutes they must be sucked
into the maelstrom.  Now, however, they opened them in amazement.

The swift rush of the log to which they clung like drowned rats had
stopped.

It took them only a few seconds to take in what had occurred.  The
great log swinging one end toward the swirling current had jammed
clear across the stream and for a time at any rate they were saved
from immediate death.  In their joy they clasped each other's hands
warmly but their first rush of relief did not last long.  As a
matter of fact they were not any nearer safely than they had been a
few minutes previous.

The log, it was true, was jammed across the stream, but the
consequent backing up of the impetuous current caused it to rush
across the boys' refuge in such volumes as to almost sweep them from
their perches.

It was very evident that they could not hold put indefinitely in
this position.

Their attention was attracted as they clung to their water-swept
tree-trunk by a dark object whirling about in the boiling pool.  It
was swept dizzily round and round in ever decreasing circles toward
the middle of the fatal vortex.  Suddenly it shot downward out of
sight, but as it did so Frank had seen something that kindled one
ray of hope--though a feeble one.  Before the canoe had taken the
fatal downward plunge it had hesitated for a minute as though caught
on something; and then the boy leader saw for the first time that in
the center of the pool there was a rock, although the water that
submerged it to the depth of an inch or so prevented its being seen
at first glance.

Frank turned to Harry and told him of his discovery.

"If we are cast into the pool let us make up our minds to get to
that rock.  Keep your mind concentrated on it.  Don't let the idea
leave you for a second and perhaps--I say 'perhaps'--we can make
it."

Harry shook his head despairingly.

"I can hardly keep my grip on this tree.  I don't believe that I
could possibly manage to swim even a few yards," he groaned.

"You must," said  Frank sharply.  "Don't give in now, Harry.   Stick
it out."

Then as a sudden thought struck him he continued.

"See here, it's no good our wasting our strength clinging to this
trunk any longer.  Sooner or later we shall be swept off and the
longer we wait the less reserve strength we shall have.  Let us
leave go now and swim for it."

Whatever reply Harry might have tendered to this desperate proposal
he was spared making, for at that moment a wave of more than
ordinary force--caused by the backed-up water striking the log--struck
him full in the face and before he knew it the boy had been washed
from the tree trunk and was being carried like a straw down the stream.

As Harry felt himself being carried along there was only one thought
in his mind.  It was not of death.  When death is right upon a man
or a boy he rarely thinks of it, but casts about for the best means
of saving himself.  Nor does--as some imaginative writers have told
us--a man's whole past life come before him at such moments.
No--the instinct of self-preservation is strongest when a human
being is in the direst need, and so it was that in Harry's mind one
thought kept hammering away like the strokes of a tolling bell.

"Try-and-make-the-rock.  Try-and-make-the-rock."

Frank's insistence had done this much.  It had caused the boy to
recollect the one hope of salvation that the desperate situation
held out.  As he was swept down the torrent Harry made no effort to
swim.  It would have been worse than useless and besides he needed
to husband his strength for the final struggle he knew was upon him.

The next minute he felt a sickening swirling sensation and realized
that he was in the whirlpool's death-grip at last.

Faster and faster the boy was hurried in ever decreasing circles.
Dizzy, half-choked with water, blinded and almost exhausted Harry,
with the tenacity of a bull dog, still clung tenaciously to the one
idea:

"Try-and-make-the-rock.  Try-and-make-the-rock."

Suddenly, he was flung against a hard substance.  With outstretched
fingers he clutched at the slimy surface as of what he realized was
the end of his journey at last.  The great stone was covered with
slimy weed, however, and his grasping fingers refused to clutch at
any friendly niche in its surface.

With a despairing cry the boy was being swept in to the terrible mouth
of the pool when he felt himself seized and pulled up out of the grip
of the torrent.  He knew no more till he opened his eyes and found
Frank by his side.  Both boys were on the rock--sitting on it in two
inches or more of water.  Fortunately in that climate the water was
not so chilly as to cause discomfort, but this was about the only
crumb of satisfaction the situation held for them.

"Well done, old fellow," said Frank as Harry opened his eyes.  "You
had a narrow escape, though."

Harry could only look at his brother gratefully.  How deep was his
debt of gratitude to him both boys realized without their talking of
it.

"How did you gain the rock, Frank?" asked Harry.

"When I saw you swept off the tree trunk I slipped off too," replied
Frank, "and when I felt myself dragged into the pool I struck out
for the rock.  I confess, though, I didn't have much hope of
reaching it till I was slammed into it with a blow that almost
cracked my ribs and knocked all the wind out of me.  I managed
however to grab hold of a depression in the surface and maintain my
grip on it.  I had hardly dragged myself up when you were hurled
against it.  I thought I had lost you, for the water pulled like a
draught-horse, but I managed to hold on to you and here we are."

"And a worse position we could not possibly be in," added Harry.

"Unless we were in there," retorted Frank pointing, not without a
shudder, to the whirling open mouth of the pool which had sucked
down the wreck of their canoe.

"What is it do you suppose?" asked Harry wonderingly.

"The mouth of a subterranean river I guess," replied Frank.  "I have
read of such things."

"But why didn't Desplaines warn us of our danger," said Harry
bitterly, "if we ever get out of this I shall tell him my opinion of
him pretty strongly.  We might have been killed and we may yet."

"He did warn us," replied Frank calmly.

"He did?"

"Yes."

"I should like to know when?"

"When we shoved off."

"You mean when he shouted something we couldn't catch and pointed
down the river?"

"That's it."

"I thought he meant there was better fishing down, here," snapped
Harry indignantly, "what idiots we were."

"Yes; not to notice how we were drifting," rejoined Frank quietly,
"it's no use to blame Mr. Desplaines for this pickle.  We have only
ourselves to be angry with.  I don't suppose he ever thought that
two boys would not notice how they were drifting in a ten mile
current."

"The point is how are we ever going to get out of it?"

How indeed?

As the boys looked about they saw little to encourage them.  The
chasm in which they were beleaguered was not more than fifteen feet
across, but on either side shot up walls of rock so steep and smooth
that not even a fern could find root on their polished surfaces.

Where the whirlpool sank into the bowels of the earth the walls came
together at an angle forming a sort of triangular prison.  At the
top of this trap the boys could see a strip of blue sky and the
outlines of the graceful tops of some bulbous stemmed palms but
nothing else.  Once a vulture sailed across the strip and sighting
the two boys came lower to investigate.  The sight of the carrion
bird made both of the boys shudder.

"Ugh, he scents a meal, he thinks we're dead already," cried Harry
disgustedly.

The sound of his voice echoed gloomily among the rocks.

"We're dead already," came back in sepulchral tones.

"I shan't try to wake that echo up again," said Harry in a low tone
and shivering at the uncanny voice of the rock.

Neither of the boys spoke for a long time.  They sat there silently,
occasionally standing up to get the stiffness out of their limbs
till the strip of sky above began to darken to gray.

"Well, here goes!" exclaimed Harry suddenly.

Frank glanced sharply up.  He did not like the wild tone in which
the words were spoken.

"What is it?" he asked sharply.

"I'm tired of this, I'm going to swim for it," replied Harry with a
foolish, hysterical laugh.

Frank saw what had happened.  The boy had become half-delirious
under the mental strain he had undergone.

"Sit down, old fellow," he said kindly, "help will come soon I am
sure."

"Yes, a steamboat will come sailing down the river and take us home
in the captain's cabin I suppose," said Harry foolishly.

But nevertheless Frank's stern command to "shut up" and not make a
foot of himself brought him to his senses and he said no more till
the stillness was broken by a sudden cry from above.

"Bosses--oh, bosses."

"Ahoy there; castaways!"

Frank looked up.

The cry of joy he gave set the echoes flying in the gloomy canyon.

It was the black face of Sikaso that was gazing down on them and
beside it was Ben Stubbs' weather-beaten countenance.  Behind them
were Billy, Lathrop and the rest.

"Hold on there and we'll get you out of that in two shakes of a
duck's tail," cheerily hailed the old adventurer.  "We guessed you'd
be here and we brought a rope as long as a man of war's cable with
us.  Lucky thing we did."

The next minute a long rope of vegetable fiber came snaking down the
side of the cliff and to one end of it clung Ben Stubbs.  As he
reached the bottom--the rope being cautiously paid out from above by
his companions--the old seaman swung himself outward from the face
of the rock and "in a brace of shakes," as he would have said, stood
alongside the two boys.  In a second his sharp eye took in Harry's
wild looks and hysterical greetings and realized what had happened.

"Now, Frank," he ordered, giving the young aviator the end of the
rope--"catch hold tight and when you are ready give the word."

"But Harry--" gasped Frank, "I can't leave him.  Let him go first."

"I'll bring him up.  He can't look after himself in the shape he's
in and you are too weak to attempt to help him.  Now no talking
back.  I'm boss now.  Up aloft with you.  Haul away there!"

The next minute Frank, clinging to the rope, was being hauled
cautiously up the side of the sheer cliff by careful hands and
shortly he was in the arms of his friends.

Ben Stubbs--to whom the rope with a weight at the end of it had been
swung pendulum wise--next appeared at the summit with Harry in his
strong grip.  But it was a white faced inanimate burden he carried.
The boy had swooned.

"He'll be all right in a few minutes," said Ben Stubbs as M.
Desplaines and the others all tried to explain at once to Frank how
Sikaso had guessed what had happened when the boys did not return.
The Krooman had led the party by secret native trails to the cliff
top.  Frank clasped the huge black's hand with real gratitude and
tears of thankfulness brimmed in his eyes.

"How can I ever thank you," he said.

"Um--white boys keep away Pool of Death, Sikaso much pleased,"
replied the Krooman turning slowly away with a sad expression on his
face.

"His own son was drowned in it several years ago," said M.
Desplaines briefly.




CHAPTER VI

A SNAP-SHOT FIEND IN TROUBLE


The morning after the events recorded in the last chapter was one of
these sparkling ones that are occasionally to be met with on the
West African coast and was the forerunner of a day of great bustle
and activity for the boys.  With the vitality of healthy youth Harry
had completely recovered and was indeed surprised to find himself
feeling so good after what he had been through.  Privately he
inspected his hair in the mirror to see if it had turned white and
was secretly much astonished to find it the same color as before.

"I wish mine would turn white or potato color or something," said
Lathrop, to whom Harry confided his expectation, "this red thatch of
mine is a nuisance.  At school I was always Brick-top or Red-Head
and out here the natives all look at my carrot-colored top-knot as
if they'd like to scalp me and keep it for a fetish."

Both boys laughed heartily over Lathrop's half-assumed vexation.  As
a matter of fact he had been the butt of many jokes in school on
account of his blazing red hair and in Africa the natives with their
love for any gaudy color had already christened him Rwome Mogo or
Red-Top.  Of this, however, he was fortunately ignorant, as he might
have been tempted to go out and dispatch half a dozen of them if he
knew of their term for him.

Down at the river bank, cross the evil-smelling lagoon at the back
of the town, Frank and Harry had their hands full directing
shouting, laughing Kroomen how to load up the canoes.  From the
canopied steam launch that lay alongside the rickety wharf the black
engineer--an American Negro--watched with great contempt their
labors, which they enlivened with songs from time to time.

"Them's de mos' good fur nuffingest niggahs I ever did see,"
remarked Mr. Rastus Johnson--that was his name--with undisguised
contempt.

Nevertheless by noon the canoes had all been leaded and the
farewells to the kind M. Desplaines and his family said.  After a
swift final inspection Frank pronounced everything ship-shape and
even Doctor Wiseman who had been fussing about as Billy said "like a
hen with one chicken--and that a lame duck," over his tin cases and
poisonous looking bottles, announced that he was ready to start.
The twelve chattering Kroomen who were to go as far as the Bambara
country with the expedition were seated two in each canoe.  They
were along simply as camp attendants and packers and would by no
means go any further than the borders of the Bambara country which
they said was the dwelling-place of "bery bad man sah."

Just as the little launch, flying the stars and stripes out of
compliment to the boys, was drawing out into the stream with a long
blast of her whistle, a tall, black form came racing along the bank
and with one bound cleared the five feet or so between the launch
and the shore.  It was Sikaso.

"So you came after all," said Frank, turning to him, after a bend in
the, river had hidden the waving Mr. Desplaines from sight and they
were settling down in the launch.

"Sikaso see in the smoke I come--I come.  If I see in smoke I no
come--I no come," remarked the Krooman.

"He's traveling light anyhow," remarked Billy.

Indeed the giant negro's only bit of baggage was a huge axe, the
handle of which was dented and scarred as if by many combats.  Billy
was about to run his thumb along its edge when with a gesture the
mighty negro waved him aside.  Instead he took Billy's handkerchief
from the young reporter's pocket and drew it gently along the axe
blade.

It fell in two pieces on each side of his blade, severed by its
razor-like edge.

"Sikaso is a good fellow to be friends with when he can make little
ones out of big ones like that," remarked Billy, picking up the two
fragments of his handkerchief, "that's a fine way to cut up a
gentleman's wardrobe."

Bit by bit as the launch drove steadily up the muddy river--from
whose jungle-grown banks arose a warm, moist vapor--Frank drew from
the grim-faced old Krooman some of his history.  He had been a
mighty warrior in the old days, he said, and the weapon be carried
was his war axe with which he had killed uncounted enemies.  A rival
tribe, however, had killed his father and mother and driven him to
the coast with the few survivors of his village.  Here he had
shipped on an American trading brig for New York where he had picked
up the knowledge of English he possessed.  He also worshiped America
as "free man's country."  But Africa had called to him and some
three years before he had returned on another ship and meant to die
there, he said.

"Why did you wish to go with us?" asked Frank as the native
concluded his story.

"It was written so in the smoke, white boss," replied the veteran
simply.  "The ju-ju in the smoke strong ju-ju.  He knows many
things."

"Is that the only reason you have for coming?"

"No, boss, I tell you truth," replied the old warrior, "some day I
find the chief who kill my father and my mother and kill my
friends."  He glanced significantly at his axe.

"In the Moon Mountains maybe I find him--maybe not.  But some day I
shall and then--"

He said no more, but as Frank remarked to Harry when the former
recounted his conversation to his brother later:

"I shouldn't much like to be that man when Sikaso meets him."

The launch and the small flotilla she towed forged steadily up the
stream all that day and at nightfall drew alongside the bank at a
spot where a clearing planted with bananas clearly indicated the
presence thereabouts of a native village.  As soon as the launch was
moored to the bank the adventurers scrambled out--not sorry of a
chance to stretch their legs--and looked about them wonderingly.
They were really in equatorial Africa at last, and even as they
looked there was a sound borne to their ears that brought home to
them strongly how very far away they were from old New York.  It was
a pulsing, rhythmic beating something like a drum and yet unlike it.
They looked questioningly at Sikaso.

"Tom-tom," said he briefly.

"Is it a friendly village, Sikaso?" inquired Doctor Wiseman.

"Friendly to some--not to all," replied the Krooman, who for some
unaccountable reason had taken a strange dislike to the professor.
"Come," he said, intoning to Frank and Harry, "we go see get
chicken, maybe pork."

"Say, can't we come along, Frank?" asked Billy and Lathrop their
faces falling.

Frank consulted Sikaso who merely said:

"Little fat white boy, with round, glass four-eyes talk too much."

"Well," laughed Frank, "I think I can promise for him that he won't
do any talking that will cause any harm this evening."

"Talk too much, indeed," grumbled Billy highly offended, "why at
home my folks were thinking of having a doctor treat me for
bashfulness I'm so retiring in my disposition."

As soon as the laugh that this remark of the disgruntled reporter
had caused had subsided--even old Sikaso giving a grim smile as he
took in the purport of it--the little party set out down a native
trail toward the village.

As the tom-tom beating increased in loudness as the village drew
near, the boys' hearts began to beat a little faster.  At last they
were about to see a real African village--such as they had read
about in Stanley's and Livingstone's books--and other less authentic
volumes.  They almost stumbled on the place as they suddenly emerged
into a clearing.  It was a strange sight that met their eyes.

Arranged in a circle were fifty huts that resembled nothing so much
as a collection of old-fashioned straw covered beehives, enlarged to
shelter human bees.  All about them women and children were
bustling; setting about getting the evening meal.  Before one hut
sat a woman, pounding something in a stone pestle--"like the
drugstore men use at home,"--whispered Lathrop to Billy.

The arrival of the little band created a stir.  The hideous old man,
with a sort of straw-bonnet, who had been beating on the antelope
skin drum called by Sikaso a "tom-tom" saw them and instantly picked
up his instrument and waddled off with as much dignity as his age
and a much distended stomach would allow him.  The younger men,
however, advanced boldly toward the party.  Some of them carried,
spears, others held Birmingham matchlocks of the kind the British
and French Governments have in vain tried to keep out of the hands
of the West African natives.  These guns are smuggled in by
hundreds, by Arab traders who exchange the "gas-pipe" weapons worth
perhaps two dollars a-piece for priceless ivory, and even human
flesh for the slave dhows.

"Seesanah (peace)," said Sikaso gravely, advancing in his turn.

"Seesanah," echoed the tribesmen, who evidently recognized Sikaso
from their greetings.  The boys stood grouped in the background--
Billy Barnes and Lathrop even viewing with some alarm the advance of
the savage-looking natives.

"Well, he seems to have fallen in with several members of his club,"
remarked the irrepressible Billy as old Sikaso and the natives
talked away at a great rate.

"I'm going to get a picture of some of these niggers when they get
through," he continued aside to Lathrop.

"What; you brought a camera?" asked the other boy.

"Sure thing," replied Billy, "and if their ugly mugs don't break the
lens, I mean to get some good snaps."

He drew a small flat folding camera from his pocket as he spoke and
got it ready for action.

"Do you think Frank would stand for it?  It might make trouble you
know," said Lathrop.

"Pshaw," retorted the cocksure Billy, "what trouble can it make?  I
wish I knew bow to say 'Look pleasant, please,' in Hottentot, or
whatever language these fellows talk."

By this time old Sikaso's 'pow-wow' was over and he motioned Frank
and Harry forward.  After they had been introduced to the chiefs and
headmen of the village, the "big chief," a villainous-looking old
party with only one eye and his legs thrust into a red shirt--into
the armholes that is, with the rest of the garment rolled round his
waist--announced he was ready to give fresh provisions for calico,
red and blue, and several sections of the brass rod that passes for
currency on the West Coast.  While Frank, Harry and Sikaso were
bargaining behind a hut, over the price to be charged for a
razor-backed porker of suspicious appearance the village suddenly
became filled with an uproar of angry shouts and tumult.

"What can be the matter?" exclaimed Frank, as the boys, followed by
the old chief and Sikaso, rushed from behind the hut to ascertain
the cause of the disturbance.

Standing in the center of a crowd of excited villagers was Billy
Barnes, his helmet knocked off and an arrow sticking through it.  He
looked scared to death as well he might, for by his side was a
stalwart young African, brandishing a heavy-bladed spear above his
head.  At the young reporter's feet lay the ill-fated camera that
had caused all the trouble.

What had happened was this.  As soon as Frank and Harry and their
companions had left him and Lathrop alone, Billy had started to
carry out his determination to take some pictures.  The first
subject he selected was a serious-faced little baby, innocent of any
clothing, that sat playing with a ragged dog at, the entrance of one
of the beehive huts.  He had just clicked the button and exclaimed:

"This will be a jim-dandy," when he felt something whistle through
the air and the next minute his hat lay at his feet with an arrow in
it.  In an instant the child's father--convinced that Billy was
putting Ju-ju medicine on the child--was upon him, armed with his
big hunting spear and followed by half the village.  Even
Billy--scared as he was--did not realize how very near to death he
actually came to being.  Sikaso's shouted words in a native dialect
caused the tribesmen to fall back but they still muttered angrily.

Stepping swiftly up to the camera Sikaso with a single blow of his
axe smashed it to pieces.

"Here, that's no way to treat my camera!" Billy was indignantly
beginning, when Frank gripped his shoulder in an iron-clutch and
whispered:

"Shut up; if you don't want to make more trouble."

Billy was starting on an angry remonstrance when he caught Frank's
eye.  The young leader was really angry and Billy prudently
refrained from saying any more.

As for Sikaso--after demolishing Billy's machine, he turned to the
tribesmen and addressing them in stately tones said--as he afterward
translated it to Frank:

"Village fools.  You see there is no magic in the little black box.
It is nothing but a child's plaything for the fat, spectacled
idiot."  (This part of the oration Frank did not communicate to
Billy.)  "You see I have smashed it.  Do I fear?  Do I look now like
a man in terror of the white man's medicine.  It is nothing.  It is
broken and gone like the cloud before the wind, like the shadow on
the mountain side."

The effect of all this was soothing and the boys left the camp, to
order some of their packmen to bring home the provisions, with light
hearts.  As for Billy his ears burned by the time Frank got through
reading him a lecture.

"I'm sorry," he said bravely, "and I won't do it again.  Gee! talk
about 'press the button and we'll do the rest.'"

"They nearly did it--didn't they," laughed Frank, his good humor
quite restored.




CHAPTIER VII

A TRAITOR IN CAMP


It was a week later, and the launch having towed the expedition as
far up the river as Frank decided was necessary--before they struck
out into the unknown land of the cannibals, winged men, and the
ivory hoard--had returned to civilization several days before,
carrying with it letters from all the adventurers which they felt
might be the last they would write for some time.  The spot selected
for the permanent camp was a sort of park-like space covered at its
edges with masses of manioc and banana bushes.  Beyond towered huge
tropical trees and beyond these again the blue outlines of the
distant Moon Mountains in which, according to old Barr's map, lay
the ivory cache.

It had been a busy week.  The Golden Eagle II had been re-erected
and her own wireless and the field wireless apparatus put in order.
As our readers who have followed this series are familiar with the
manner of setting up the great Chester aeroplane and her fittings,
it would be tedious to repeat the description of the process.
Suffice it to say that thanks to the clever simplicity of the
"knock-down" arrangement, by which the ship could be taken apart and
set up again, the operation of equipping her for active work was a
comparatively light one.  The extra gasoline and supplies for the
camp in general were stored in a separate tent removed from the
circle in which the boys' tents and those of Ben Stubbs and
Professor Wiseman were pitched.

There was, too, a newcomer in the camp--a Portuguese named Diego de
Barros.  He was not a particularly well-favored individual, but he
bore the reputation of having great power over the natives and of
being very friendly to the white traders who penetrated into the
interior.  Once or twice there had been ugly talk about his being in
league with the Arab slave and ivory traders, but he had managed to
clear his name and along the Ivory Coast enjoyed the reputation of
being an honest, reliable man.  He had joined the boys' camp a few
days before and his manner of coming was this.

While everybody was busy getting things in shape there had come a
loud hail from the quarters of the native helpers, just outside the
white man's encampment, announcing that a canoe was coming up the
river.  All hands had hastened to the river bank to find de Barros
just putting his foot ashore from the canoe in which two natives had
paddled him from the coast.  He had with him some bales of cotton
goods and a few gewgaws of various kinds and was bound, so he said,
on a trading expedition into the back country.  Further down the
river he had heard, he explained, that the boys were camped where he
found them, and he had determined to pay them a visit.  The brief
stay that the boys had interpreted this as meaning, however, had
extended itself into three days and still Diego showed no
inclination to leave.

"If he doesn't move on soon I shall be compelled to ask him to go,"
said Frank in an annoyed tone to Harry.  "I don't want to be
inhospitable, but we can't afford to have strangers hanging round
the camp, there is too much at stake."

Harry agreed with him and the two boys decided to tell the Portuguese
that evening as tactfully as possible that they were on a private
enterprise and could not accommodate strangers.  This decision
arrived at, Frank turned to the steel strong box that was never out
of his sight and drew from it the precious map of the Moon Mountains.
Seated at the little camp-table--(the conversation just related had
taken place in the Boy Aviators' tent)--the two pored over the
document for hours.  With dividers, compass and parallel rulers Frank,
who was a skilled navigator, laid out an aerial course that would
bring them, he calculated, unerringly to the spot marked by a red
cross where--so old Luther Barr declared--lay the ivory that was to
save Mr. Beasley from financial ruin and disgrace.

Frank laid his finger on the spot and exclaimed enthusiastically:

"There it is, Harry, and we are not so far from it now.  In a few
days we shall know whether we are on a wild-goose chase or not."

"Why, no doubt has ever entered your head that the ivory is there?"
questioned Harry.

"Well, old fellow, you know there are others interested in this
ivory beside ourselves--Muley-Hassan for instance."

"You think he had got ahead of us?"

"I did not say I thought so, I only say that it is possible that he
may have done so."

"How could he have got wind of our coming?"

"In Africa there is a sort of underground wire for news," replied
Frank.  "I have no doubt that hundreds of natives far in the
interior are by this time apprised of our coming."

Harry looked alarmed.

"That's bad," he said.

"Well, it couldn't be helped: but we may have other enemies nearer
at hand."

"What do you mean?"

"That I don't like the looks of that Portuguese fellow.  If he got
wind of what we are doing he would be likely to ruin the whole
object of our expedition."

"That's so.  We'll have to get rid of him."

"Well, we are going to, and if he won't go for gentle means we'll
try rough ones."

"Hullo, what's that?" exclaimed Harry suddenly.

The flap at the end of the tent toward which both of their backs had
been turned had been suddenly drawn aside and in one quick, backward
glance Harry made out the smiling figure of de Barros standing in
the doorway.  It might have been fancy, but he thought for a minute
that the Portuguese had a peculiarly villainous expression on his
dark, handsome features.

"Ah, senors," he said, as Frank, with a quick movement swept the map
off the table--but not before de Barros's quick eyes had spied it.
Fearing to replace the precious chart in the strong box, while the
Portuguese lingered, Frank tucked it into his pocket.

"Ah, senors, good afternoon," grinned the unwelcome visitor.  "I
have come to say 'adios.'  I am going up the river to-night and may
not see you again for a long time."

"I am sorry to have you leave," said Frank with a heartfelt wish
that de Barros would hasten his departure.

"I knew you would be," smiled the Portuguese, "but it is the lot of
man to meet and part.  Adios, senors, I go to make ready."

He vanished as suddenly as he had come upon the scene.

"What do you make of that?" inquired Harry.

"I don't know what to think.  I have an idea that he was listening
to every word of our conversation just now and that he saw the map
before I had time to sweep it off the table."

Harry looked vexed.

"That's tough luck," he said.  "If he overheard even a part of our
talk he must realize the object of our presence in Africa.  And," he
went on, "I don't know a man on the Dark Continent whom I would
trust less than Diego de Barros, even the little we've seen of him."

"It can't be helped now," said Frank briefly; "come on, let's go and
put the finishing touches on the good old Eagle."

They worked the rest of the afternoon putting the big aeroplane in
shape for her flight to the Moon Mountains which it had been
determined to make the next day.  It was almost dusk when Harry, who
was working over the engines, asked Frank for the reserve park-plug
box.

"It's in one of the canoes.  I'll go and get it," said Frank, and at
once set off toward the river bank for that purpose.  His path led
through a thick grove of bamboos which hid him from the view of the
camp after he had traversed a short distance.  As he merged on the
river bank, whistling softly to himself, the young leader suddenly
felt himself pinioned by arms that seemed of enormous strength--
though, as the attack had come from behind, he could not see the
faces of his assailants.  The next minute he was lying flat on his
back, bound and helpless with a bit of greasy cloth shoved in his
mouth for a gag.

"Keep still, senor, and you shall not be hurt;" said a quiet voice
near at hand, and Frank saw bending above him the sallow features of
the smiling Portuguese.

"I just have to trouble you for that map I saw you put in your
pocket, that is all," went on his captor, while the two huge negroes
who had made Frank prisoner stood to one side immovable as carved
figures,

"It is lucky for me that you came down to the river bank," grinned
the Portuguese as he ran his hand over Frank's clothes, to ascertain
the hiding-place of the precious map of the ivory cache, "otherwise
I should have had to delay my departure till to-night, and possibly
have cut your throat while you slept."

Frank felt as if his heart would burst with rage and mortification
as the greasy, smiling Portuguese deliberately drew out the
priceless document and gazed at it in triumph.  He laid it on the
ground beside him while lie resumed his search for other clues.

"That ivory belongs to my master--Muley-Hassan--now," he sneered;
"did you think for a minute that we would ever let you white fools
get it back again."

It was well for the Portuguese that Frank's hands were not free
then.  Had they been the dark-skinned traitor would have had a fight
on his hands in a few seconds.  But suddenly events took a strange
turn.

The two blacks uttered a sharp cry of warning as the bushes parted
and a huge form dashed out, whirling about its head a glistening
axe.

It was Sikaso!

The next minute would have been Diego's last but that his two
followers lifted him to his feet and, picking him up like a child,
ran for his canoe with him.  With a few rapid strokes they were in
midstream and paddling up the river with powerful strokes while
Sikaso raged impotently on the shore.

"Oh for one of the white men's fire-tubes!" he sighed, and even as
he spoke a sharp reminder of the efficiency of these same
"fire-tubes" whizzed past his ear in the shape of a bullet from
Diego's revolver.

In a few steps the old black was beside his young leader and with a
couple of strokes of his keen blade had set him free.

"Quick, Sikaso; the canoes--we must pursue him.  Call the boys and
Ben while I cast off the canoes.  Quick, we have not a minute to
lose."

Although Diego in his hurry had not carried off the map but left it
lying on the ground, still Frank realized that the Portuguese had
not actually needed the document to aid Muley-Hassan to find the
cache.  The Arab was no doubt familiar with the location anyway, but
to head off all danger of the boys getting there first, it was vital
to stop Diego at all costs.  In a few bounds Frank reached the
little indentation in the bank where the canoes were kept.

As he gained it he fell back with a groan and, brave boy as he was,
he leaned weakly against a tree for support as the true extent of
the crushing disaster that had occurred was borne in on him.

The canoes were gone!

The cunning rascal, Diego, had devised his plan well.

The painters of all the craft had been cut, and by this time they
were doubtless miles down the stream.




CHAPTER VIII

A BATTLE IN THE AIR

The consternation with which the news of the loss of the canoes was
received by the young adventurers may be imagined.  It meant that
they were cut off from communication with the coast entirely unless
some unforeseen circumstances arose.   But in spite of the oppression
that naturally affected them at the first news of their serious loss,
Frank's confident manner had its effect in restoring some sort of
hope.  Like the born leader that he was, Frank, the minute he
recovered from the first effects of his bitter dismay, set about
cheering up the others.

"We've always got the Golden Eagle," he comforted, "and anyway it's
likely if no one stops them, that some at least of the canoes will
drift down the river to the coast.  M. Desplaines will no doubt be
able to surmise something serious has happened when he hears of
their arrival and will send aid.  In the meantime we have to
consider what we are to do about the ivory cache."

As a matter of fact, as the boys learned later, none of the canoes
ever reached the coast, being intercepted by river-tribes.

"I vote for going ahead," cried Harry, catching the optimistic note
that his brother's words conveyed.

"That's the stuff," cried the young leader, "that is exactly what I
was going to propose."

"How about you, red-top?" asked Billy turning to Lathrop.

"Of course I'm on," was the reply.

"I hate to dash your enthusiasm," said Frank, "but you fellows must
see that it is impossible for all of us to go.  My plan is to take
Ben Stubbs along and leave you fellows and Sikaso here to guard the
camp.  Then, too, there is the possibility of a relief expedition
arriving as soon as they discover that we have lost our canoes."

Old Sikaso leant apart on his mighty war-axe.  He seemed to regret
heartily that he had not had an opportunity of testing its metal on
the head of the knavish Portuguese.

"What do you say to that plan, Sikaso?" asked Frank, who already
placed a high value on the old warrior's judgment.

"That it is good, my white brother.  Sikaso will stay with the
four-eyed one and the ruddy-haired one and we will see that no harm
comes to the camp of the young white warriors."

"It is well," replied Frank, who was falling into a trick of
addressing the stately Krooman in the same grandiloquent fashion as
the latter was in the habit of using, "I place my trust in you."

"Hum," snorted Billy, "four-eyes and red-top that's a nice
combination for you!  I'd like to do something to show that old chap
that we can do just as much as anyone else when it comes to a
show-down."

This remark, however, was made sotto voce to Lathrop, as Billy
really stood in great awe of the six foot-two of ebony flesh and
muscle that was Sikaso.

But Stubbs was delighted at his selection to accompany the boys in
their aerial dash for the ivory cache.  He spent half the night by
lantern light pottering about the great craft and stocking her up
with provisions and equipment for the journey.  By the time he had
finished it was almost midnight and he turned in to join the boys in
the land of dreams where Frank and Harry, and doubtless the others,
too, were already busy shooting down Diegos and hippopotami and
flitting through the air above the great African forest and
performing all sorts of wonderful feats.

At dawn everybody was up and about and after farewells had been said
the Chester boys and their sturdy old companion clambered into the
chassis of their craft.  Frank had already laid out his course,
which lay about two points west of north.  The boy calculated that
this direction would bring them within a few miles at any rate of
the cache.  To find it they would have to trust to persistence and a
modicum of luck.

Old Sikaso, who had, of course, never seen anything even remotely
resembling an aeroplane, stood apart from the excited group
clustered about the big craft and gazed at it with astonishment, not
unmixed with awe.  The other Kroomen--the packers and camp-workers,
however, gathered close about the machine and the boys had a lot of
trouble keeping their busy fingers from unscrewing nuts and
loosening turnbuckles.

"Anything more like a pack of monkeys on a picnic I never saw,"
exclaimed Billy as for the twentieth time he chased a long, skinny
native away from the propellers, where he would have assuredly been
decapitated if he had remained till the engine was started.

A few turns with the clutch thrown out showed the engine was running
as true as on the day the Golden Eagle made her trial trip.  The
muffler was cut out and the effect of the wide-open exhaust on the
Kroomen was magical.  Within a second from the time that Harry threw
in the switch and the gatling gun uproar of the exhaust made itself
manifest, not a solitary one was to be seen.  From the greenery of
the jungle that rimmed the clearing, however, their frightened faces
could be seen peering, like some strange sort of fruit among the
tropical growth.  Only old Sikaso stood his ground.

But even that stolid old warrior grasped his great war-axe a little
tighter and stood erect as if about to face an unknown enemy as jets
of blue flame and smoke shot from the detonating exhaust.

"All ready, Harry?" cried Frank to the younger boy who was at his
old station by the engines.

"Ay, ay!" came the response in a hearty tone.  "Then let her go."

With a quick movement Frank threw in the clutch.

The mighty propellers began to beat the air with the whirring sound
of a swarm of gigantic locusts in full flight, and after a short run
the great aeroplane took the air in a long graceful rising arc.
Half an hour later, to the watchers in the camp, she was little more
than a speck against the sky.

Frank, his eye constantly on the compass, kept the ship on a true
course for the Moon Mountains which, now that they were flying far
above the dense forest region, lay a rugged mass of blue and brown,
piled like some giant's playthings--on the northwestern horizon.

Even from the distance at which the boys viewed them they conveyed
an almost sinister impression in their rugged shapes.  Their harsh
outlines cut the sky in a serrated line like the teeth of a huge
saw.

"Look, look, Frank!" shouted Harry suddenly as they were passing
high over a small clearing.

Both Frank and Ben peered over the side in answer to the boy's
excited hail.

Far below them was a strange sight.

In the center of the clearing were four huge African elephants
solemnly conducting a sort of Brobdingnaggian game of tag.  One of
the great beasts would tap the other with its trunk and then would
scamper away till it in turn was "tapped" by a blow that would have
swept a small regiment off its feet.

Frank pushed over a lever and swung the ship in a circle so that
they might watch the great animals to better advantage.  Suddenly
the boys saw one of the elephants, evidently seized by sudden rage,
start goring one of its companions with its huge tusks.  The
attacked animal had no chance, and but for the boys would speedily
have been killed.

"I'm going to give that big bully a shot," exclaimed Harry, and he
got out one of the heavy rifles from the rack under the starboard
transom.

"Wait, I'll drop a bit," said Frank.

In response to his manipulation the aeroplane dropped till she
hovered not more than two hundred feet above the great animals.
Then a strange thing happened.  The shadow of the craft fell upon
the center of the clearing in front of the dueling beasts and the
on-looking pachyderms, and as it did so the bully stopped goring its
mate and gave a snort of astonishment.

Its note of surprise quickly changed to a loud trumpet of terror as
the great pachyderm saw swooping above it what must have appeared to
it an aerial inhabitant even larger than itself.  Its note of fright
was echoed in a chorus that sounded like an assemblage of cracked
trumpets as the others also sensed the impending danger.

"Now let him have it," shouted Frank.

Harry's rifle cracked and the big bully staggered.  Twice more the
boy fired and the huge creature staggered on to its knees and then
with a mighty groan rolled over on its side.  The others, even the
wounded one, had made off as soon as they had caught sight of the
hovering Golden Eagle.

Even from the height at which they were the boys could see that the
dead animal had an enormous pair of tusks, no doubt extremely
valuable.

"We ought to have them there figure-heads," commented Ben Stubbs.
"What do you say if we drop down and get them?"

Frank looked at his watch.  It was half-past nine.

"We cannot be more than a hundred miles now from the foot of the
range," he said, "and I suppose we have plenty of time.  We might as
well drop and get them as let some native tribe have the find and
then get skinned out of them by an Arab trader."

As he spoke the boy set the planes for descending and the Golden
Eagle settled down--after a few minutes rapid falling--fairly in the
center of the clearing.  It was almost a fairylike spot.  On every
side it was hedged in by the densest jungle vegetation, the solid
walls being broken here and there by elephant paths leading off into
the green tangle.

The little glade in which the Golden Eagle had settled was covered
with short, yellow grass and had been trampled almost bare of
vegetation, apparently by the gambols of countless generations of
elephants.

"This must be one of the elephant playgrounds I have read about,"
exclaimed Harry, looking about him.

"No doubt it is," replied Frank.  "But look at those tusks, why
there's ivory enough there alone to give us all a nice wad of pocket
money."

Ben Stubbs, with one of the small axes, at once set about hacking
out the dead elephant's huge tusks and a long job it was.  Finally,
however, he managed to cut them free and clear and the boys loaded
them into the aeroplane.

"Now we are all ready for a fresh start," said Frank as they
clambered in after him and settled down in their places; but a
startling interruption occurred.

With a wild yell, that struck a sudden chill to the heart of every
one of the little group, a band of beings that at first sight looked
like nothing so much as huge gorillas, burst from the forest on
every side.

Their heads were misshapen and flat and their protruding lips were
daubed with white and red clay which gave them a ghastly unearthly
look.  From their ears hung huge ivory pendants.  They carried
elephant skin shields and were armed with spears and bow and arrows.
As if they did not consider themselves sufficiently hideous, several
of the tribe had cut their faces in long stripes and the hardly
healed scars of these wounds rendered their already sinister faces
terrifying indeed.

Desperately Harry threw over the wheel and the engines started
faithfully to respond but not before half a dozen of the savages had
thrown themselves on to the aeroplane.

Their weight held her down although she scudded over the ground; and
in the meantime the other natives started pouring a shower of arrows
and spears into her.  Fortunately none of these struck the boys
although Frank felt an arrow whiz through the loose sleeve of his
shirt.

"Get those fellows off or I can't get the ship up," he yelled.

Harry and Ben Stubbs fired their automatics into the clinging mass
of savages.

Two dropped and the aeroplane began to rise but the others
desperately clung on.

"Get 'em off," shouted Frank, as he desperately strove to raise the
air-craft.

As he spoke he fell back with a cry of pain.

An arrow had struck him on the shoulder inflicting a painful wound.

Like a flash Harry took in the situation and leaped to the steering
wheel.  As he did so the savage with whom he had been contending
clambered clear into the chassis.  At the same instant Ben Stubbs'
revolver dispatched the last of the men clinging to the planes and
the Golden Eagle began to rise.

As she shot upward the savage who had climbed into the chassis gave
a wild shriek of real terror.  But his outburst didn't come before
he had made a savage lunge at Ben Stubbs with a short heavy knife.
The solo adventurer dived under the black's arm and struck it upward
as he lunged and the weapon went whirling groundward out of the
air-ship.

With a cry of despair the savage rushed to the edge of the car and
was about to throw himself into empty air when Ben leaped forward to
try to restrain him.

But it was too late.

As the boys' sturdy companion gallantly attempted to save the
savage's life a flight of arrows whizzed up from below.

With a groan the man on the edge of the car pitched forward into
open space, pierced to the heart with an arrow sped by one of his
own tribesmen.  Down he shot like a stone to the earth below, while
the Golden Eagle--as if rejoicing in her escape, shot upward and
onward.




CHAPTER IX

THE VOICE OF THE MOUNTAIN


Frank's wound fortunately turned out to be nothing very serious--
though painful enough--and after it had been treated with
antiseptics from the medicine chest he declared that, aside from the
stiffness and soreness, he felt no ill effect.

"Those fellows certainly gave us a sample of what we may expect,"
remarked Harry, examining the hole in his shirt where the arrow had
ripped through.

"It was quite as narrow an escape as I care to experience," agreed
Frank.  "How about you, Ben?"

"Wall," said the old adventurer, "I don't know as how I think that
kind of excitement is as beneficial fer the health as the rest
cure."

Meanwhile the Golden Eagle, plowing through the clear African air at
fifty miles an hour, rapidly drew nearer and nearer to the
mysterious Moon Mountains.

As they neared the range the extraordinary character of it was
revealed more and more clearly.  Seamed with deep gloomy abysses and
almost bare of vegetation, except a few scanty groves of palms and
the hardier tropical trees, they seemed indeed fitted to be the
theater of dark mysteries and the haunt of savage tribes.

"Well," exclaimed Harry, as be scrutinized the strange mountain mass
through the glasses, "I should say that if those Winged Men are to
be found anywhere, here is where they'd reside."

"I should think they'd use their wings to get out--a nastier looking
lot of mountains I never saw," was Ben's reply.

Frank made no comment, but the sinister character of the mountains
they were so rapidly approaching impressed itself on his mind
nevertheless.  Eagerly he scanned the range for the first sign of
"The Upturned Face."  Harry and Ben, too, gave quite as eager
scrutiny toward the discovery of this striking mark of the ivory's
hiding-place.

All at once it shot into view with a suddenness that made the boys'
beads swim.

It was as clear as daylight.  The line of the mountain for which
Frank had the Golden Eagle II now directly headed was unmistakably
the outline also of a hawk-nosed facet.

If the mountains themselves had an evil, menacing look, the stone
face possessed this same quality in an infinitely greater degree.

"Well, if we've got to go looking for ivory right under that face
the sooner we find it the better," exclaimed Ben.  "I'd hate to be
shipmates with the fellow who sat for that portrait."

"No human being ever sat for it, Ben," laughed Frank; "it's a mere
freak of nature which has so disposed the mountain mass at this
point as to give the semblance of what the map-maker terms The
Upturned Face."

"Well, if I had a mug like that I'd turn it down instead of up
before some one did it for me," was Ben's comment.

The Golden Eagle landed on a plateau about halfway up the mountain,
beneath the upturned face.  It made an almost ideal camping-place,
considering the rugged nature of their surroundings.  In one part of
it a small grove of bananas and palms had taken root, and their
smiling greenery offered a refreshing contrast to the dark
oppressive gloom of the giant rock masses piled all about.  From the
center of this oasis in the rocky range bubbled a tiny spring of
water as clear and cold as if it had been filtered and iced.
Frank's first act was to send out a wireless to the River Camp,
telling of their arrival.

"Well, thank goodness, we've got something green and pleasant to
look at," remarked Ben, as they set about transforming the chassis
of the Golden Eagle into a comfortable tent by means of running up
the canvas curtains on the aluminum frames provided for that
purpose.  Thus equipped, the chassis served the uses of an improved
tent, as the floor was well above the ground and out of all danger
of the unwholesome, vapors rising from the ground and also the
scorpions and other reptiles.

But if the oasis itself was a pretty spot, it was made doubly so by
the contrast it afforded to the scenery surrounding it.  On all
sides shot up frowning walls of rugged black rock which seemed to
have been torn and ripped in some remote period by a terrific
convulsion of nature.  In places, too, the rock masses seemed to
have been seared by subterranean fires.  Frank gazed upward at the
terrific character of the scenery about them.

"We shall need the rope-ladder," he announced suddenly after a long
silence.

"The rope-ladder?" inquired Harry, "what for?"

Frank laughed.

"I mean the rope-ladder we use in the Golden Eagle.  As you know,
the only way to locate the cache is to strike a direct line down
from the nose of the upturned face.  That will bring us to the small
cairn or pile of rocks that marks the Arab's hiding-place."

"He could hardly have chosen a better," remarked Harry.  "Who would
ever guess, unless they had the key to the mystery, that these
mountains held such a fortune in tusks."

The rest of that day was spent in overhauling the outfit which they
would need to use on their expedition of the morrow.  Luckily the
boots they wore had been fitted with "hob-nails" so that they were
ideal for the tough climb that they had ahead of them.  Each member
of the three was to carry a pick and of course they all were to be
armed, carrying several rounds of ammunition each in their
cartridge-belts.

That night after a supper of fried ham, canned corn and pancakes--all
cooked by the skilful Ben over a fire of wood collected from the
little grove--Frank sent out a wireless to the members of the camp
on the river bank and felt much reassured when Lathrop's "All
well--good luck," came back through the air.  It was delightfully
cool on the mountain-side after the oppressive fetid air of the
river and its neighborhood, and as Ben had remarked before they
turned in:

"Fine weather for sleeping."

But sleep would not come to Frank.  He tossed and turned on his
transom bed and several times gazed out into the night through the
canvas curtains.  An unaccountable feeling of unrest possessed him.
Could they get the ivory out of the cache before Muley-Hassan and
his band arrived by land?

Fast as they had traveled through the air Frank realized that the
Arab, who doubtless by this time had been informed by the
treacherous Diego of the boys' bold dash, would push on at furious
speed in order to head them off.  That he would come accompanied by
a well-armed band Frank could not doubt.  He and Harry and Ben could
only put up a feeble resistance against such an attack.  There was
only one chance to secure the ivory and that was to get at it before
the Arab arrived.  It all depended then on how quickly they could
find the cache. Frank lit the lantern and shielding it so that it
would not strike in the eyes of his sleeping brother, drew out the
map and scanned it attentively.

Yes, here were the directions written in the queer hand of
Muley-Hassan's follower.

"A line from the nose straight down to the cairn of stones."

It seemed simple enough and certainly the nose of the Upturned Face
was as clearly to be made out as a ship at sea. But Frank had been
too long trained in the hard school of adventure to underestimate
the difficulties of any piece of work.  They faced a hard job and
none realized the fact better than the young leader.

At last he blew the lantern out and once more composed himself to
sleep.  He was just dozing off when a sufficiently startling
interruption occurred.  One which drove all further thoughts of rest
from his head.

It was an extraordinary sound that brought the boy out of his bed
with a bound and caused him to clutch his revolver with a heart that
beat loud and thick in spite of himself.

Clutching his weapon the boy rushed to the door of the chassis tent
and gazed out.

There was a bright moon which threw into inky blackness the
depressions of the rugged mountains and threw up their projections
into a blue glare.  It was almost as light as day under that
wonderful African moon.  Had there been any one near the boy must
have been able to see them.

But look as he would there was not a soul in sight.  All about him
stretched the barren frowning mountains sleeping under the moon.

But the sound that he had heard?

There was no mistaking it.  It had been too like the low humming of
a human voice for him to have been misled.  Perhaps he had been
dreaming?

But as if to give the lie to any such supposition the strange sound
that had so alarmed him at that moment made itself manifest once
more:

"A-hooo-A-AH-HOOO-00-a-ho-ho-ho-o-!"

It started softly and gradually ran up the scale till it reached a
crescendo shout and then died out in a soft sound like a woman's
wail.  Heard anywhere the sound would have been alarming enough, but
coming as it did in the midst of these unknown, mysterious Mountains
of the Moon it struck a chill to the boy's heart and caused his
scalp to tighten in a manner that even the bravest man or boy in the
world would have had no reason to feel shame over.

A human enemy, a foe he could see, Frank would have faced with iron
nerve; but this strange wailing noise coming from what quarter of
the compass he could not judge--was so uncanny that he was really
disturbed.  He bounded into the chassis and roused Ben and Harry.
He had hardly whispered to them the extraordinary intelligence when
again the voice arose.

"A-ho-ho-h-o-o-o-A-h-hoo-ho-AH-HO-HO-O-O-O-AH-ho-h-o-o-o-o-o-o!"

"Well, who?" roared Ben angrily, "come out and show yourself, you
human hyena, and I'll put so much lead in your system you'll be
worth a nickel a pound.  Come, you old Ah-Hoo, and I'll show you who
I am quick enough--shiver my topsails!"

But the only reply to Ben's tirade was the dismal echo of his voice
among the rocky chasms.

"Shiver my topsails!" roared the echo and then the hills bandied the
cry about from ridge to ridge till it died out in a whisper:

"My topsails!"

"Hum," remarked Ben, "I don't think I'll talk so loud around here.
There seem to be a lot of folks listening.  Such a dreary hole as
this I never--"

"Never," sighed the echoes, "--never."

"Here, I can't stand this," cried Harry.  "I'm going to send a
bullet up there the next time that fellow starts 'Ah-hooing."'

But as the strange mournful cry rang out once more the boys paused
in bewilderment.

There was no locating the sound.

It seemed to fill the air.  To come from every quarter of the
compass at once.




CHAPTER X

THE ARAB'S CACHE


The mysterious cries were not repeated that night although the boys
laid awake till daylight listening for any repetition.  No theory
they could advance, although these ranged all the way from cannibals
and gorillas to ghosts, had any effect on the solution of the
mystery.  They finally agreed to trust to solving it in some chance
way, and like sensible boys did not continue to worry themselves
over the unsolvable.

Frank's first action was to send out a wireless to the river camp
and to his great relief he found that events there were still
proceeding with the same regularity as before.  Nothing had occurred
to mar the even life of the young adventurers left behind.  This was
the tenor of the message, but there was something about it that
worried Frank.  Lathrop, he knew, was an expert wireless operator,
but the sending that he performed that morning was so jerky and
irregular that the rankest amateur might have done better.

"What is the matter?" asked Frank sharply after the sending had
become even more unskilled and shaky.

There was no answer; which caused Frank a vague feeling of
apprehension.  He speedily drove this impression from his mind,
however, with:

"Pshaw! the sleepless night I passed has made me nervous."

After breakfast there was so much to be done that there was no more
time to waste on gloomy forebodings and the boys started, as soon as
the camp had been put in order, on their expedition up the
mountain-side to the Upturned Face--which was to be the starting
point for the uncovering of the secret ivory hoard.

The climb was quite as stiff as Frank had anticipated and, laden as
they were with the rope-ladder and the other equipment, it was
rendered even tougher.  All three carried water-canteens covered
with wet felt, containing half-a-gallon each.  Frank had insisted on
this as it was doubtful if they could find water at the summit of
the mountain.

As the sun rose higher in the sky and beat down on the bare rock
ridges over which the adventurers were making their way, it became
as uncomfortable as any expedition on which the boys had ever beer
engaged.

"Talk about New Mexico or Death Valley," exclaimed Harry, "I feel
like a piece of butter rolled up in a paper and I've melted."

"I feel like a Welsh rarebit myself," laughed Frank, "how about you,
Ben?"

"I feel like a pot of boiling tar with a fire lighted under me,"
growled the veteran angrily; "consarn these rocks, I'd give a whole
lot for a bit of that shade we left behind us."

Despite the discomfort and the heat, however, they struggled on up
the mountain-side, frequently using the rope-ladder to get over
rough places, and at about noon they stood beneath the steep rock
cliff that formed the nose of the upturned face.

It was easy enough then to reach a spot below the tip and Frank,
with a long cord he had brought for the purpose, laid out a straight
line from the point down the southern slope of the mountain-side.
While they were busy about this they were startled by a repetition
of the same strange cry, half-warning, half-savage, that they had
been so alarmed by the night before.

"A-ho-o-o-o-AH-H-O-O-O-a-h-o-o-hoo-o-o-o-o!"

"Great Scott," yelled Harry, "what on earth do you think of that?"

Frank--considerably startled himself--had, however, made a
determined effort to ascertain the source of the sound as it rose
and fell in its strange cadence.

"I've got it!" he shouted; now with a cry of triumph.

"Got what?" cried Harry, as if he feared his brother had suddenly
become infected with some strange complaint--"rabies or the pip?"

"The noise--I mean I know where it comes from," cried the excited
boy.

"Where?" chorused Ben and Harry.

"From somewhere about the Upturned Face," cried Frank triumphantly,
"Hark!"

The strange wailing cry rang out once more.  They all listened
intently.

Sure enough it seemed to proceed from the sinister countenance
carved in the living rock above them.

"Well, here's where we end this mystery for all time," shouted
Frank, drawing his revolver, "who is game to follow me?"

Of course Harry and Ben rushed to his side, and while the echo of
the mysterious cry was still sobbing and sighing among the crags
they dashed back up the mountain-side utterly oblivious now to the
heat or anything but their determination to discover who or what had
uttered the extraordinary cry.  The side of the nose--or the nostril
so to speak--was formed of a wall of rock fully twelve feet in
height.

"You fellows give me a boost up there and I'll travel right along
the face till I find out where the racket comes from."

On Ben's strong shoulders Frank was soon hoisted up to a height
where he could lay hold of a projecting bit of rock and shin himself
up on to the top of the nose.

"Look out he doesn't think you are a fly and try to brush you off,"
laughed Harry from below.

"No danger of that," shouted back Frank, "unless I lit on him in the
Golden Eagle."

The surface of the face was as remarkable as its profile.

Apparently some forgotten tribe had at some time or other been
struck by the facial outline of the rocks and had cut into the flat
surface, which was upturned to the sky, eyes and a mouth, the latter
well provided with teeth, in each of which was drilled a tiny
triangular hole.

While Frank was puzzling over the meaning of these apertures there
came a repetition of the weird cry, but this time the lad was so
startled that he almost lost his balance and fell backward.

The call seemed to proceed from his very feet.  Then, all at once,
he realized what it was.

The strange sounds proceeded from the mouth of the stone face.

Frank ran to the edge of the steep declivity that formed the nose.

"Say, Harry, and you too, Ben, examine the surface below there very
carefully for any holes.  They will probably be small ones and in a
row."

"None this side," announced the searchers after a lengthy quest.

"Try the other," ordered Frank.

They did so and after a few minutes of careful scrutiny Harry
shouted that they had found a row of small holes pierced in the rock
just below where Frank stood.

"Then we have solved the mystery of the voice," exclaimed Frank.

"What do you mean?" demanded Harry.

"That it is nothing more or less than an arrangement of holes
through which, when the wind blows in a stiff puff, air is forced
with violence enough to cause the cry that disturbed us so much last
night," was the reply.

This indeed was the solution, and had the boys known it there are
many such rocks in Africa, carved out by some forgotten race, and
the weird cries that the vent-holes give out in the wind doubtless
acted as a powerful "fetish" to keep away troublesome enemies.

"No wonder the niggers down below don't come near the Moon
Mountains," said Harry, as they all buckled over the simple
explanation of the phenomenon that had caused them so much alarm.
"I wouldn't care to, myself, unless I knew just what made that cry."

"It certainly was as depressing as anything I ever heard," said
Frank, "and now having solved the great mystery--let's get back to
work."

The three adventurers went at the job with a will.  The line was
about a hundred feet long and the method of procedure was this:
Frank tested the straightness of the line, as accurately as possible
with his eye, while Ben and Harry carried it stretched between them.
The end of each hundred feet was signalized by a stone, and Harry,
who was at the end of the line, carried his end to this mark before
they laid out a fresh hundred feet.  In this way they must have
measured off very nearly half-a-mile of the mountain-side when Frank
gave a sudden sharp cry and pointed to a depression in the dark
range immediately below them.  As the others looked they echoed his
cry and gave a dash forward.

Directly beneath them, about in the center of the little dip, was a
cairn of rough stones perhaps four feet in height.  In a few bounds
they had reached the pile, which they knew meant the discovery of
the ivory cache and the end of the most difficult part of their
expedition.  Little did they imagine the amazing things that were
yet to happen to them and of which they were but on the threshold.

"Good Lord, look at that, boys!" exclaimed Frank, as they stood at
the foot of the cairn.

There was a good reason for the boy's exclamation.

Distributed around the base of the pile were a dozen or, more human
skulls.

"Are they those of white men?" asked Harry in an awed tone.  Frank
shook his head.

"No, they are those of negroes I believe," he replied after a
careful examination, "and I imagine that Muley-Hassan killed them
after they erected the cache so that they would not be able to
spread the knowledge of its whereabouts to any of the marauding
tribes who might even brave the ghostly voice when such a great
treasure of ivory tempted."

A shout from Ben, who had been walking round the pile examining it
from every view-point interrupted them.  They looked up and saw the
old adventurer pointing to the mountain summit where it cut the sky.
Outlined against the deep azure was the object that had caused his
exclamation.  It was the figure of a man that had apparently been
watching them intently.

But as they gazed the strange, crouched form suddenly vanished.




CHAPTER XI

THE AGE OF SIKASO

It was late afternoon of the day that Frank, Harry and Ben had left
the River Camp.  Lathrop, Billy, Barnes and old Sikaso had wandered
into the jungle with their rifles, intent on bringing down some sort
of game to replenish the camp larder.  For hours they tramped about
in the thick jungle and a fair measure of success had fallen to
their rifles.  Shortly before sundown the trio met in a glade not
more than a mile from the camp and compared notes.  To Billy's gun
had fallen a plump young deer and Lathrop had brought down, not
without a feeling of considerable pride, a species of wild hog which
Sikaso proclaimed with a grunt was "heap good."

Flushed with triumph and carrying their own bag, the young hunters
set out for the camp, arriving there at dusk.  As has been told, it
was not long after that that Frank's wireless from the Moon
Mountains winged its way through the air and Lathrop was able to
flash back in response an "all-well" message.  The boys turned in
early, Billy and Lathrop to their tent and old Sikaso to the rough
shelter he had contrived for himself and which he declared was far
more comfortable than any tent.  Like a wild beast the savage old
warrior disliked to have anything approaching a roof over him.  It
appeared to savor too much of a trap of some kind.

Billy might have been asleep five hours or so and it was approaching
midnight when he heard a noise outside the tent door and a second
later old Sikaso announced his presence by a whispered:

"Awake, Four-eyes, there is danger."

"What do you mean, Sikaso," demanded the half asleep reporter,
"danger to our friends?"

"No; to us, and here and soon," was the disquieting response,
"arouse your friend.  We have no time to lose."

Billy was wide awake now and made a motion as if he would light the
lantern.

Sikaso stopped him with a quick gesture.

"Do not light the lamp, my white brother," he whispered in the same
tense tones, "to do so would be to reveal to those who are now
approaching that we are awake and expect them.  Rather let us
pretend that we are unaware that they come and spring upon them like
the leopard when she is least expected."

"Yes, but--" exclaimed Billy in a bewildered tone, "what do you
mean, Sikaso, what enemies are coming?  How do you know that they
are approaching?"

"I have seen it in the smoke," was the somber reply; "the smoke
never lies.  After I lay down on my skins I could not sleep, I felt
there was danger approaching us.  From where I knew not.  So I made
the "fetish" fire.  In it I saw a band of men coming toward us down
the river and at the head of them was a dark man--a man you know
well, my white brother with the four eyes."

"Diego!" exclaimed Billy divining the other's thought.

"Yes, Diego; cursed be the day that my war-axe did not cleave his
ugly skull; but beside Diego there is another.  Hearken to the words
of Sikaso, the elephant in his rage is not more merciless, the
serpent not more cunning, the crocodile not more savage in onslaught
t