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[Illustration: "Suddenly I heard the Professor's voice just as if he
were right out there on the desert."]




                             THE RADIO BOYS
                         SEEK THE LOST ATLANTIS


                         By GERALD BRECKENRIDGE

                               Author of
   _"The Radio Boys on the Mexican Border," "The Radio Boys with the
  Revenue Guards," "The Radio Boys on Secret Service Duty," "The Radio
 Boys Search for the Inca's Treasure," "The Radio Boys Rescue the Lost
        Alaska Expedition," "The Radio Boys in Darkest Africa."_

                         [Illustration: Radio]

                              Frontispiece


                           A. L. BURT COMPANY
                         Publishers    New York


                                  THE
                           RADIO BOYS SERIES

                A SERIES OF STORIES FOR BOYS OF ALL AGES
                         By GERALD BRECKENRIDGE

  The Radio Boys on the Mexican Border
  The Radio Boys on Secret Service Duty
  The Radio Boys with the Revenue Guards
  The Radio Boys Search for the Inca's Treasure
  The Radio Boys Rescue the Lost Alaska Expedition
  The Radio Boys Seek the Lost Atlantis
  The Radio Boys In Darkest Africa

                            Copyright, 1923
                         By A. L. BURT COMPANY
                           Made in "U. S. A."




                                PREFACE


Dear Boys:

One of the greatest, if not _the_ greatest story of all the ages, is the
legend of Atlantis. According to this legend, there existed at one time
a great continent in the Atlantic Ocean not far west of the Pillars of
Hercules, those two great rocks of Gibraltar in Spain and Jibel Kebir in
Morocco which guard the entrance to the Mediterranean.

The legend says that this continent was the first region in which man
rose from barbarism to civilization, and that in the course of ages it
became a populous and mighty nation from whose shores immigrants went
out to settle the shores of the Gulf of Mexico, the valley of the
Mississippi, the valley of the Amazon, the Pacific coast of South
America, the shores of the Mediterranean, of the Baltic, the Black Sea
and the Caspian and the western coast of Europe and Africa.

From this continent, continues the legend, the first colonists
penetrated western Africa clear to Egypt where they took root in the
Nile valley and developed what is today conceded to be the earliest
known civilization.

Many other startling statements are made in this legend. For instance,
it is said that the civilizations of the Incas in Peru and the Mayas in
Central America, like the civilization of Egypt, were derived from
Atlantis through immigration; that the Atlanteans were the first
manufacturers of iron, and that the implements of the "Bronze Age" in
Europe were derived from them; that the Phoenician alphabet, parents of
all European alphabets, was derived from Atlantis, bearing a startling
resemblance to the alphabet of the vanished race of the Mayas in Central
America, whose ancient cities are just this very day, as you can read in
your papers, being unearthed; that the gods and goddesses of the ancient
Greeks, the Phoenicians, the Hindus and the Scandinavians were merely
the kings and queens and heroes of Atlantis, about whose real historic
actions the migrating Atlanteans remembered stories which eventually
went to create the mythology of their descendants.

There is much else of this sort, all culminating in the great
outstanding feature of the legend which is that Atlantis was destroyed
in a terrible convulsion of nature, and sank beneath the ocean with
almost all its inhabitants, leaving only a few of the loftiest peaks
sticking above the water, which today comprise the islands of Madeira,
the Azores and the Bermudas.

From this cataclysm a few Atlanteans, it is related, escaped to
neighboring shores in rafts and ships, bearing their tale of horror. And
from these tales arose the legend of a great Flood or Deluge, which has
survived to our own time in the Book of Genesis in the Bible and in the
mythologies of all peoples of both the Old and the New Worlds.

This is the legend, then, and that for thousands of years it was
regarded as a fable proves nothing.

People used to believe the legends of the buried cities of Pompeii and
Herculaneum were myths. They believed so for a thousand years, before
archaeologists exposed the ruins. The historian Herodotus was called
"the father of liars" for a thousand years, because he wrote of the
wonders of the ancient civilizations of the Nile valley and of Chaldea.
But now it is known he spoke the truth.

It is so with this legend of Atlantis, of which the great Greek, Plato,
has left us the most detailed account. All these thousands of years
since Plato wrote his account of Atlantis, 400 years before the Birth of
Christ, he has been regarded as a poetizer. But in the light of recent
researches, which really are just beginning, it appears as if what he
wrote was not legend but history, and as if, indeed, his story is one of
the most valuable documents which have come down to us from antiquity.

Some day you must hunt up and read for yourselves a book entitled
"Atlantis or the Antediluvian World." Written by Ignatius Donnelly, it
was published by Harper & Brothers in 1882. In it are collected Plato's
story of Atlantis and a wealth of evidences which go to prove, in the
author's opinion, that Atlantis did actually exist, that it was the home
of the white race, the Semitic race and, perhaps, the Turanian, and that
it was destroyed by a convulsion of Nature.

Since Donnelly's book, investigation has gone further. Savants uncovered
near the southern edge of the Sahara Desert about the time of the
outbreak of the Great War the ruins of two great cities of an unknown
civilization, believed to have been seats of a migration from Atlantis.
The war, however, halted their research, and up to a recent period the
investigation had not been resumed. In one of these cities, people of an
unknown white strain resided in a semi-savage state. I, therefore, have
made them the background for this story, and that you will like it is
the hope of

                                                             THE AUTHOR.

  Emerson Hill,
  Staten Island, N. Y.
  1923.




                                CONTENTS


  I. Introduction.                                                     3
  II. A Cry for Help.                                                 11
  III. The Mystery at the Oasis.                                      17
  IV. The Mystery Deepens.                                            23
  V. Allola's Story.                                                  32
  VI. The Tale of the Slave Trader.                                   41
  VII. Chasing Ostriches.                                             50
  VIII. Bob's Fight Against Odds.                                     58
  IX. A Puzzling Prophecy.                                            67
  X. Squelched by an Ostrich.                                         76
  XI. The Stranger Revives.                                           85
  XII. Amrath Speaks.                                                 94
  XIII. Korakum Reached.                                             101
  XIV. A New Radio Station.                                          110
  XV. Meeting the Revolutionists.                                    119
  XVI. Revolt of the Exiles.                                         129
  XVII. The Fight for the Pass.                                      136
  XVIII. A Dark Hour.                                                147
  XIX. At Low Ebb.                                                   153
  XX. An Old Friend Appears.                                         159
  XXI. Reunion.                                                      166
  XXII. Frank to the Rescue.                                         176
  XXIII. The Fliers Warn Korakum.                                    182
  XXIV. Into the Coliseum.                                           190
  XXV. A Surprise for the Janissaries.                               199
  XXVI. The Revolutionists Succeed.                                  207
  XXVII. Athensi Falls.                                              213
  XXVIII. Conclusion.                                                219




                 THE RADIO BOYS SEEK THE LOST ATLANTIS




                               CHAPTER I.
                             INTRODUCTION.


Jack Hampton wearily passed a hand across his eyes. Would they never
sight the oasis at which Ali had promised they would arrive at the end
of the day's march? Even after many days of travel on camel-back, Jack
had not become sufficiently accustomed to the soft-footed swaying brute
to make a long day's ride a pleasure.

And this was a long day's ride indeed. Except for a brief halt at noon
the caravan had been on the march across the lifeless sand dunes of the
desert, unbroken by trees, rocks, animals or human beings, unbroken by
anything, in fact, except occasional stunted bushes, since dawn. In
another half hour the sun would descend, and if the promised oasis were
not sighted by then, they would be forced to spend another night on the
desert.

Looking back from his position at the head of the column, Jack could see
Bob Temple and Frank Merrick, both mounted as was he, behind them a half
dozen shuffling camels with astride each among the bundles a swarthy
Arab enfolded in the inevitable jillab, from the folds of which stuck
out a long-barrelled rifle, and bringing up the rear Jack's father and
Ali, his head man, both engaged in conversation.

The loop aerial rigged up on Frank's camel caught Jack's gaze, and his
eyes brightened. He decided he would break the monotony of this desert
travel by kidding his friend. And with that purpose in view, he halted
his camel, to await Frank's approach.

To himself Jack chuckled as he thought of the bewilderment and wonder
which Frank had aroused amongst the camel drivers by his aerial.
Attached to a light frame strapped to the camel's hump, ground wire
trailing between the animal's feet, Frank had rigged up the set the day
before upon Ali's declaration that another day would see them at the
Oasis Aiz-Or. He wanted to be in a position to receive any message which
Professor Souchard, a Swiss savant, who awaited their coming, might send
out. For with him Professor Souchard had a duplex radio apparatus for
both sending and receiving, which the boys jointly had devised.

Many months before Professor Souchard had entered the Sahara to prepare
for their coming. Not that it was his first visit to the Great Desert,
however. On the contrary, twenty years of his life had been spent in
poking about its endless reaches in search of the ruins of an incredibly
ancient city which he had reason to believe had been founded in
prehistoric times by colonists from the lost continent of Atlantis, that
fabled land in the Atlantic ocean which had been the seat of all
civilization and had been swallowed up in a tremendous cataclysm of
Nature giving rise to the universal legends of The Flood.

Toward the end of his period of explorations, Professor Souchard had
come to an oasis lying far from the few known routes, the Oasis of
Aiz-Or, inhabited by a small desert tribe. From it he had glimpsed far
to the southward the peaks of a mountain range. When he asked the Arabs
what mountains lay there, they had replied it was the Land of Shaitun,
which in English means Satan. The mountains were accursed said the
Arabs, and all who ventured near were never heard of again.

At least five days' travel intervened, said Professor Souchard's hosts,
with no water holes in the direct route, although three small springs
bubbling from beneath great rocks lay somewhere between the oasis and
the mountain wall. But without guides, a traveller would be unable to
find them.

Nothing daunted, Professor Souchard accompanied by his faithful
companion, Ben Hassim, had set out. For the mountains of Shaitun, he
believed, were unknown to geographers. And the ancient Egyptian
inscriptions which spoke of the great city of the past for which he had
been searching through the years referred to the mountains surrounding
it. Perhaps, therefore, the city he sought was within that mountain
wall.

The scientist and Ben Hassim finally did manage to attain to the foot of
the mountain wall, which rose unbroken from the plain, on the fifth day.
But their supply of water was exhausted, they were semi-delirious. For
two days they travelled along the base of the wall, seeking some pass or
valley which pierced the barrier.

At length on the seventh day they came upon a stone-paved road and,
scarcely able to believe the evidence of their senses, they began to
follow along it into the mountains. Before proceeding far, however, they
were overcome by fever and thirst and fell insensible. In this
condition, they were found and rescued.

Upon recovery they found themselves amidst great stone ruins of
ponderous architecture, in the midst of a luxuriant valley watered by a
broad stream encircling one side, which emerged from a tunnel in the
mountains and disappeared again into the mountains, not to reach the
surface more.

Their rescuers were kindly men, several of whom possessed a good command
of English, and they were white. But as Professor Souchard's knowledge
of English was strictly limited, they could not understand each other
well.

However, while being nursed back to strength, the scientist managed to
make out that his rescuers were political refugees from another city in
the heart of the mountains known as Athensi, and that in this city and
the plateaus surrounding it dwelt a white race of semi-civilized people
ruled over by a religious Oligarchy. His rescuers were men of superior
intelligence and a high state of culture and that they had travelled
about the world was apparent. With his slight knowledge of English and a
smattering of their tongue which he picked up, he was able to come to
that conclusion.

To him it became apparent that the ruined city of Korakum, overgrown by
rank jungle growth and in the midst of which the Athensian exiles
cultivated little patches of garden, was the city he had been seeking.
But the little he could learn of Athensi fired his imagination.
Apparently, at some dim age in the past the settlers of this ruined city
which had been called Korakum had withdrawn into the mountain country
and built Athensi, where were palaces, temples, a vast Coliseum, above
all, a great Library housing thousands of papyrus rolls.

If he could only gain access to Athensi, thought Professor Souchard,
what wonders and mysteries of the ancient world, perhaps of a
civilization existing in Atlantis before the Flood, would be revealed.

However, on his recovery, the exiles told him it was best for him to
depart before the Athensian authorities discovered his presence, as they
wished to preserve isolation from the outside world and did not want
their secret discovered. Therefore, after supplying him with water and
food, they started him and Ben Hassim on the return journey.

Well did Jack recall the arrival of Professor Souchard at his father's
home on Long Island with this tale. Mr. Hampton, himself an explorer and
engineer of wide reputation, had been enthusiastic. He had promised the
scientist, whose funds had become exhausted and who was unable to obtain
backing for further explorations in war-exhausted Europe, to finance an
expedition to Athensi.

With this promise, Professor Souchard had returned to Africa, and as
soon as he could put his affairs in shape for prolonged absence, Mr.
Hampton had followed. With him he had taken Jack and the latter's close
chums, Bob Temple and Frank Merrick.

Those of our readers familiar with the three Radio Boys by reason of
following their adventures chronicled in "The Radio Boys on the Mexican
Border," "With the Revenue Guards," "On Secret Service Duty," "In Search
of the Inca Treasure" and "Rescuing the Lost Expedition," will realize
that three more reliable young fellows in just such a situation could
not be found.

Jack and Bob were both six feet tall, and Bob in addition was possessed
of extraordinary strength. As for Frank, an orphan, who made his home
with Bob on the Temple estate, adjoining that of the Hamptons' near
Southampton, Long Island, what he lacked in inches and girth, was made
up in quickness of intellect. All three were students at Yale.

This was the way matters stood, with the party at length after its trip
across the Sahara from Khartum drawing near the Oasis Aiz-Or, when Jack
paused to await the approach of his comrades.

As Frank drew nearer, Jack smiled. He was thinking of the other's
comical appearance. Wrapped in the voluminous jillab which all wore as
it provided greater protection against sand and heat than European
clothing, Frank was crowned by a sun helmet, startling by contrast, and
beneath it wore headphones clamped over his ears.

Jack was on the point of calling out some laughing remark about the
latter's vain wait for a message from Professor Souchard, when Frank's
face suddenly betrayed alarm. And with a shout he tore the headset from
his ears, sending the sun helmet spinning out on the floor of the
desert. Turning about, he beckoned wildly for Mr. Hampton and Ali to
approach.

"What is it?" shouted Jack. "What did you hear?"

For, that Frank had received some message filling him with alarm was
apparent.

Frank did not reply. His face grew pale beneath the heavy tan.




                              CHAPTER II.
                            A CRY FOR HELP.


The long rays of the setting sun, which almost touched the horizon, were
flung across the desert, turning it into dazzling gold, as Mr. Hampton
and Ali pushed their camels close to where the three boys had come
together. The camels stood with feet spread apart, seemingly asleep.
Jack and Bob, who also had drawn close, were bombarding Frank with
questions and, almost inarticulate at first, he had just begun to answer
when Mr. Hampton and Ali arrived.

In the background crowded the half dozen Arab guards, sensing something
amiss.

"A cry for help," Mr. Hampton heard Frank say. "The Professor was
sending out an appeal to us." Frank looked wildly around at the group.
"Great Scott, can't we do something?" he appealed.

"Calm down, Frank," said Mr. Hampton. "Tell us about it, and then we can
decide what to do."

Frank nodded as he got a grip on his emotions.

"Well, maybe, I was a little inarticulate," he said, with a rueful
smile. "But, just think. Here I was, bumping along on my camel, and half
asleep. I had the headpiece on, the phones to my ears. But I hadn't any
real idea I'd hear anything. What's there to hear, way out here, away
from all the world? The only chance was that Professor Souchard would
take a notion to broadcast something for our benefit.

"Then it happened."

He paused and looked at the others, before swallowing and resuming, with
his face still pale.

"Suddenly I heard the Professor's voice, just as if he were right out
there on the desert."

Frank pointed off into the sunset, and involuntarily, so strong was the
impression created by his words, the others stared, too. All, however,
in a moment restored their gaze to Frank's face--that is, all except
Ali. He continued to stare through the sun wrinkles about his sharp,
dark eyes. He even raised a strong brown hand to shield his eyes from
the sun. The others, however, paid him no attention. They had eyes only
for Frank.

"Yes, sir," re-iterated Frank, "it sounded as if the Professor were
right out there on the desert. His voice was agonized, he was stammering
as if in a frenzy of terror.

"'If you hear me, my friends, come. This is Souchard. I have run fast to
get to this little instrument. It is a raid. I think they are white. I
think they are Athensians, and----'"

Dramatically, sensing the breathless interest of his auditors, Frank
paused.

"And," he said slowly, "that was all. No, not really all, for there was
a sudden sharp crash that almost broke my ear drums. Then silence."

He stopped. They continued to gaze at him. Nobody spoke for a long
minute. Every face was pale. Every one of Frank's three white auditors
breathed faster. Even the Arab guards, bunched in the background, unable
to understand Frank's rapid narrative in English, still understood
something was amiss. Only Ali paid no attention.

"This is terrible, Frank," said Mr. Hampton, breaking the weighty
silence. "You're sure you could not have been mistaken?"

Frank shrugged his shoulders under the flowing burnoose such as they all
wore, finding it more effectual to keep out the heat and wind-whipped
sand than any European costume.

"Just as I told you, Mr. Hampton," he said. "The Professor's voice might
have been coming from no farther than you."

"Ah, I thought so."

The interruption came from Ali, whose command of English was fluent. Ali
was a cosmopolitan from the teeming streets of Cairo, a man of many
languages.

Now he turned to Mr. Hampton, pointing off to the west, straight into
the eye of the sinking sun, which now was half below the horizon.

"See," he said.

Faintly limned against the shining disk of the sun, yet as clear as an
etching, could be seen a tracery of lines that might, by active stretch
of the imagination, be considered palm trees.

"The Oasis of Aiz-Or," said Ali.

"What. That close," cried Mr. Hampton. "Come, perhaps, we can still be
in time to help. That cannot be far."

"Five miles at least," said Ali. "But we shall hurry."

Turning, he addressed the Arabs in their own tongue. On each face came a
gleam of determination. These were men who could be depended upon, men,
moreover, not only ready but eager, in all likelihood, for a fight.

Those whose only knowledge of camels has been gleaned from circus or zoo
cannot appreciate the speed of which these desert travellers are capable
under urging. A clatter of grunts, punches and camel cries succeeded
Ali's command to his men, and then the caravan was under way.

Lurching this way and that, clinging for dear life, the boys and Mr.
Hampton managed not only to retain their seats, but also to keep up with
the others. On galloped the camels, every moment exhorted to further
efforts. For a few minutes, while the sun still held, the trees of the
oasis outlined against it seemed literally to hurl themselves forward,
so rapid was the pace of the approaching party. Then the sun dropped out
of sight, literally fell away, and was succeeded at once by darkness.

Still the party kept on without abating its pace, the long legs of the
camels eating up the miles at an unbelievably rapid rate. Jack, Bob and
Frank had no time for thought. They were wracked in every limb. They
felt as if they were being torn apart on a torture machine. Still they
clung, while their camels surged forward with the rest.

Then Ali's voice was raised in a sharp command, and at once the other
Arabs repeated certain cries to their camels which slowed them down. The
boys had the good sense to realize what was wanted, and they, too,
emitted the necessary grunts which seemed to constitute the language of
camels.

What was the explanation of this maneuvre? Simply that Ali saw looming
ahead the shadowy outlines of the tall feathered palm trees constituting
the little oasis, and had no desire to charge blindly without
preparation or plan.

Mr. Hampton urged his camel alongside that of Ali, and the boys also
approached. Although twenty-five years older than his son, Mr. Hampton
had an iron frame inured to fatigue through years of roughing it in the
out-of-the-way places of the world. He was less blown as a result of the
wild ride than the young fellows.

Long since he had given up any idea of keeping the boys out of danger.
All were strong and cool-headed in emergencies, and he had received
plenty of evidence during recent years that they could take care of
themselves.

Rapidly he outlined what was to be done. Let all dismount, hobble the
camels and leave them in charge of two of Ali's men, and the balance of
the party, consisting of Ali, four Arabs, the three boys and himself,
nine in all, would advance afoot. In this way, the noise of their
approach could be minimized. Besides, so far as four of their number
were concerned, they would be better able to render a good account of
themselves than if on camel back.

Ali acquiesced, the necessary commands were given, and all caused their
camels to kneel while they dismounted. Then two of the number were left
adjusting hobbles and guarding the animals, while the others spread out
a yard apart, and began to steal forward.




                              CHAPTER III.
                       THE MYSTERY AT THE OASIS.


There is something wonderfully exhilarating in night on the open desert.
The boys felt it, so did Mr. Hampton. Who knows? Perhaps Ali and the
Arabs were subject to this mysterious influence, too. Shortly, a little
after seven as they knew from experience, the moon would be up,
silvering the plain. All now, however, was in darkness except for the
dim light of the stars. Yet it was a darkness filled with caressing
breezes and the feeling of beauty.

Despite the adventurous quest upon which they were embarked, despite the
possibility, nay, the probability, that in a moment the night would be
shattered with strife and death, each found himself yielding insensibly
to this softening influence.

Suddenly the howling of a dog broke the stillness. It was a long wailing
cry that made the nerves quiver and caused each member of the party to
grow tense. When does a dog howl like that? Ali and the Arabs knew. The
rest, with their sensitive intelligences, guessed at the meaning. That
howl meant mourning over a fallen master.

As if it were a signal, other dogs joined in. A whole chorus of wailing
notes effectively shattered the stillness of night.

"Forward."

Mr. Hampton's whisper ran along the ragged line.

Again they advanced. Still not a sound from the oasis except the howls
of dogs.

The trees were closer now. Their leafy tops stood out stark against the
sky. Abruptly as the seashore meets the land and ends, sand, the desert
sand, met the thick grass of the oasis and ended. They were under the
trees, in the grass, pushing forward.

Suddenly the moon rose, and a new weird light fell over everything,
bringing out the outlines of the trees, shedding a silver radiance
between their tall trunks. Jack, who was in the middle of the advancing
line, paused, startled. Some huge objects, black and indefinite in
shape, seemed to rise out of the ground in front of him.

What were they? He glanced hastily at the shadowy forms of his
companions, whom he could discern among the trees right and left of him.
Evidently, they, too, had seen, for they also had paused.

The line moved forward, Ali and the Arabs taking the initiative. Jack
advanced, too. If Ali felt no alarm, certainly he was not going to
exhibit any. Bob and Frank experienced similar feelings.

Then, in a moment, the nature of those strange objects became apparent.
They were tents--great rambling horsehair tents of the Bedouins or
desert Arabs.

The howling of the dogs continued, at no great distance now, seeming to
come from the other side of the tents which were a half dozen in number.
Not a light was apparent. Not a human sound fell on their ears. A low
command from Ali to his Arabs, from Mr. Hampton to the boys, drew in the
scattered members of the line to a central group. They were at the rear
of one of the Bedouin tents, the largest of all, probably that of the
tribal sheik. So close were they that they could have put out their
hands and touched it.

"Strangest thing I ever saw," muttered Mr. Hampton. "Not a soul around
apparently. Out with your flashlights now, fellows, and we'll make a
search. Keep your rifles ready to deal with emergencies."

Around to the front of the tent they stole. The trees were thinned out.
In the weird glow of the moon which penetrated to this open space,
everything was plain to be seen. The five tents stood a little apart
from each other, clustered to one side. On the other side could be seen
a well, its water gleaming in the moonlight.

Not a soul advanced to meet them. Not a light showed in any tent.

The howling of the dogs continued, Ali with a muttered word of command
to his Arabs strode forward, passing the well on his left. Two of his
followers went at his heels. In a moment he was among the dogs, kicking
them aside, as their sharper yelping testified.

Before Mr. Hampton or any of those left behind could begin an
investigation of the tents, Ali came flying back, leaving his two Arabs
behind him.

"Three men dead," he declared tersely. "One the Professor, another Ben
Hassim, the third a strange white man in strange clothes."

"I'll have a look," said Mr. Hampton. "In the meantime, do you
investigate the tents to see if there is anybody here."

Ali nodded and Mr. Hampton strode away, calling the boys to follow. Jack
turned as he passed the well. Already Ali, flashlight in hand, was
diving into the biggest of the tents, with an Arab at his heels, while
another was stationed in the open space on guard. The cautious Ali was
taking no chance of being surprised in the rear.

A little beyond the well, they came upon the two Arabs left in charge of
the dead by Ali, while the dogs, reduced to low whines, crouched or
circled at a distance. The bodies of the fallen men had been
straightened. They lay on their backs, their faces upturned to the
moonlight.

Mr. Hampton knelt beside the body of the Professor, placing one hand on
his forehead and the other on his wrist. He shook his head sorrowfully
and raised a heavy glance toward the boys.

"Dead," he said.

No sign of life could be discovered, either, in the body of Ben Hassim.

Then that of the third man was approached. As Ali had said, he was a
white man, of medium height, with a sharp, hawk-like cast of features.
Even in the weird moonlight, the strangeness of the white toga-like
garment, belted in at the waist with a dark heavy cord, falling to a
little below the knees and leaving the legs bare, could be seen. Unlike
the others, whose eyes were opened in death, this man lay with his eyes
closed. Mr. Hampton bent forward with a sharp exclamation.

After making a quick examination, during which the boys whispered to
each other in comment on the man's unusual dress and appearance, Mr.
Hampton got quickly to his feet.

"This man shows signs of life," he said. "Two of you carry him back to
the tents."

He turned to the Arabs and directed them to take up Ben Hassim's body.
Then he and Jack lifted that of the Professor. Bob and Frank, bearing
the body of the third man, led the way, and the little procession moved
back to the clearing.

They were met by Ali, who in the short time of their absence had managed
to search all the tents, and had succeeded in finding neither living nor
dead except for one old woman who could hardly be said to be either.
Although alive, she was half dead from fright.




                              CHAPTER IV.
                          THE MYSTERY DEEPENS.


The old woman was given in charge of the Arabs to be questioned later.
She was so old that she went without a veil when in the presence of men.
Reduced to a state of abject fear by events yet to be learned, she was
left in charge of two Arabs placed on guard by a fire lighted in the
middle of the open enclosure.

The first thing to be done was to look after the wounded man. Mr.
Hampton ordered him carried into the large tent, which had been that of
the Sheik Abraham, leader of this little tribe of Arabs which inhabited
the Oasis Aiz-Or. Grass mats were scattered about the roomy interior,
and there was a divan covered with faded rugs. On a little tabouret
burned a lamp of palmolive oil which gave off a not unpleasant odor.

The boys who followed close at the heels of the Arab bearers looked
around with curiosity, while the body of the wounded man was laid on the
divan and Mr. Hampton began making a critical examination to determine
the extent of his injuries.

Casting their flashlights into the shadows not penetrated by the feeble
rays of the lamp which Ali had found and lighted, the boys discerned a
heavy curtain cutting off one part of the tent. Ali came up to them.

"That is the women's quarters," he said. "Sheik Abraham kept his three
wives there. I have never been here before. The oasis is far from all
travel routes and Sheik Abraham rarely, if ever, got to the bigger
desert towns and villages. But I believe he must have had three wives,
for there are that many divans. Ordinarily it would be death for an
unbeliever to penetrate into the women's quarters. Sheik Abraham is a
Mohammedan, of course." He shrugged. Ali was a cosmopolite and to the
boys spoke cynically of all religion. Yet they had seen him spread his
prayer mat and perform his devotions night and morning with the other
Arabs.

"Now," said Ali, lifting the curtain, "you can see an Arab sheik's
selemlik without fear. Behold."

After all, the boys were disappointed. Desultory reading about Arab
sheiks had led them to expect they knew not what. Certainly, handsome
tents, softly carpeted, filled with silks and perfumes, with shining
lances and silver-mounted rifles. As for the selemlik, or women's
quarters, they believed such a place would be a nest of beauty.

Instead, there were three or four divans covered with rugs of faded
patterns and colors, a cheap cracked mirror hanging askew on one wall of
the tent, a veil thrown awry over one divan, and that was all.

Ali explained.

"The women left in haste," he said. "Perhaps, they were carried off by
the attackers. Yet they had time to bundle their clothes and take them
along."

Questions burned on the boys' lips, and they flung them at Ali. Who had
attacked? Had the whole tribe been carried off into captivity? Why had
the Professor and his faithful servant, Ben Hassim, alone been killed?

Ali shook his head. They must wait until the old woman was in a state to
be questioned. Perhaps, too, some information could be wrung from the
lips of the wounded captive, although it was possible from his
appearance that he did not speak Arabic. Never had Ali seen a man
dressed as he, and a white man, too. It was all a nightmare,
non-understandable. Let the boys wait until Allah sent an
interpretation.

With this they had to be content. Dropping the curtain, they emerged
into the main portion of the tent, finding Mr. Hampton absorbed in his
attempt to revive the wounded prisoner. He looked up only long enough to
explain he had been unable to find any wound from bullet, sword or
spear. The man had been felled by a blow on the head. Mr. Hampton was
not certain whether concussion of the brain had followed.

One of the Arabs he had despatched to bring up the two guards and the
camels, left in the desert. When the caravan arrived, he would be able
to get his medical and surgical supplies. Then he would see what further
could be done. Possessed of a knowledge of rude surgery acquired in his
out-of-the-way expeditions, Mr. Hampton was able to set broken limbs and
perform minor operations, but trepanning was beyond him. Should that
prove necessary, he would be helpless to aid the fallen man.

"We're going to have a look at the Professor's tent, Dad," explained
Jack, following his father's remarks. "We'll be back soon. Want to see
what happened to his radio outfit, for one thing."

Mr. Hampton nodded, and the boys trooped out at Ali's heels. Three Arabs
hunkered over the fire, for the night had turned chill, as it invariably
does on the great desert. Beside them was the figure of the old woman.
They were not speaking, but sat motionless, staring into the flames. The
fourth man had gone for his two comrades left in charge of the camels.

Ali led the way into another tent. While the boys played their
flashlights about the interior, he found and lighted an oil lamp, a
shallow copper vessel with a spout that held a wick. When this was
lighted, they examined the place more closely.

Smaller than Sheik Abraham's tent, there was no dividing curtain, as
here was no need for a selemlik. On two divans had slept the Professor
and Ben Hassim. Everything was in wildest confusion. Three long narrow
trunks were broken open and their contents of clothing, books, maps and
scientific instruments were scattered about. These things the boys put
aside for later inspection.

"Where was his radio?" asked Jack.

A cry from Bob answered.

"Look here, fellows," called the big husky. "Smashed as if with an ax. A
perfect ruin if ever I saw one."

They hastened to his side. The broadcasting set which the boys had made
themselves and which had been their gift to Professor Souchard, had been
made to fit into one--the smallest--of the three shallow trunks. It had
included a folding table on which it was to be mounted.

The table had been set up in one corner of the tent. Instead of dry
cells, the current was supplied by a motor. Everything had been properly
set up in the method into which the boys had drilled the Professor. The
key had been screwed to the middle of the table and near the front edge.
Back of it had been placed the high tension condenser, with the
oscillation transformer still farther in the rear. To the left of the
oscillation transformer had been placed the alternating current
transformer and in front of it was the quenched gap.

Even though the table and its contents had been smashed, as if with an
ax, this much could be seen. Doubtless, too, the wiring had been done
according to directions. Otherwise, the Professor would not have been
able, of course, to communicate with Frank. But the wrecking of the
station had been so thoroughly carried out that it was impossible to
tell.

Where the wires from the motor had been connected with a single-throw,
double-pole switch, which in turn was connected with the primary coil of
the alternating power transformer and with one post of the key, the
other post of which was connected with the switch, there was now only a
mass of tangled and chopped wires. As for the connections between the
motor of the rotary spark gap to the power circuit, and between the
secondary coil, the quenched spark gap, the condenser and the primary
coil of the oscillation transformer, thus completing the closed
oscillation circuit, they too, were a tangled mess.

The telephone instrument wired as an alternative to the key, thus
permitting the sending either of telegraph or conversation, had been
ripped away and ground into the hard-packed earth of the floor. At first
it could not be found, but Frank stubbed a foot against it finally.

The three boys looked at each other, while Ali stood to one side.

"If you can make anything out of that, you fellows," said Bob, "you'll
be going some. That's all I can say."

Jack shook his head dubiously.

"Oh, come," expostulated Frank, who never liked to take a dare, and this
looked like a dare to him, "give me time and I'll have that fixed up.
We've got all sorts of radio supplies in our luggage, you know, and as
long as the motor hasn't been wrecked we can fix this up. I'll bet on
it."

The motor had not been subject to the general attack, as a matter of
fact. Standing below the table, perhaps it had been overlooked. At
Frank's words, therefore, the others nodded.

"That's right, old thing," said Jack, slapping him on the back. "We'll
pitch in on this tomorrow, and we'll have it fixed up in no time. That
is," he added, pausing, "if something else doesn't come up for us to do,
like----"

"Like what?" demanded Bob.

"Well, either defending ourselves or pursuing the raiders."

"Pursuing them?" asked Frank.

Jack nodded.

"When that old woman is able to talk, we'll find out what happened here
tonight," he said. "If Sheik Abraham and his few tribesmen and women
were carried off captive, and there is a chance we can help them, I know
father will want to do it."

"And I'll want to do it, too," said big Bob, gruffly. "Darned shame
these people getting into trouble, and perhaps on our account, too."

"Our account?" It was Jack's turn to look surprised.

"Sure thing," said Bob, slangily. "Why not? How else can you figure it?
Who was killed? Nobody but the Professor and Ben Hassim, the two men who
had penetrated the Shaitun Mountains and found this old city and learned
about a way to get to Athensi. Who killed 'em? Well, by the looks of
that wounded fellow your father is doctoring, it was a raiding party of
Athensians."

Everybody looked thoughtful. As for Jack, he felt increased respect for
his big friend's powers of reasoning.

"But, great Scott, Bob, what would bring them six or seven days across
the desert?" he demanded. "As far as the Professor ever could discover,
they never left their hidden strongholds. Oh, of course, once a year a
party went to Gao. But I understood that lay in an opposite direction
from this oasis across the desert."

Ali, who had been an interested listener to this discussion,
interrupted.

"Perhaps, these strange people learned the Professor meant to disturb
their privacy and bring the world to their doors," he said. "And they
resented, and took this method of putting a stop to it."

"But how could they have learned about him or his plans?" demurred
Frank. "Oh, this is a mess. Well, when that wounded chap finds his
tongue, maybe we'll learn something. Or when the old woman becomes able
to answer questions. Anyway, let's look around here for any letters or
papers or other things the Professor might have left, and then go back
to your father, Jack."




                               CHAPTER V.
                            ALLOLA'S STORY.


Several days passed, however, during which the wounded Athensian, for
such they all considered him to be, lay in a stupor resembling death.
Little enough had the party to go on toward solving the mystery of the
raid on the Oasis Aiz-Or.

The old woman whose name was Allola, and who proved to be the Sheik
Abraham's mother, recovered the use of her wits and her tongue, but what
information she was able to supply was only scanty.

She knew the Professor and Ben Hassim, not alone from their most recent
stay with her tribe, but from their former visit. "The Crazy One," she
described the Professor, bowing her head and hushing her voice in
reverence as she did so, for among all primitive peoples those afflicted
with insanity are regarded as under the special protection of
Providence. And, although the Professor in reality was far from insane,
yet these desert Bedouins so considered him because of his
eccentricities and his search for a lost city and his invasion of the
dread Shaitun Mountains.

When the Professor with Ben Hassim had arrived a second time at their
isolated and almost forgotten oasis, Allola said the Sheik Abraham, her
son, together with the dozen men of the tribe and twice as many boys
greeted him with joy, while she and the women with their faces veiled
watched curiously from the tents.

A welcome visitor was the Professor to this little tribe living apart
from the world which rarely saw or entertained anybody from the outside.
For the men he brought cigarettes, for the women many cakes of sweet
chocolate. They were very grateful, and a tent had been set aside for
him, and women assigned to look after his needs.

Days had slipped into weeks and weeks into months, while the Professor
and Ben Hassim stayed on. Frequently they would depart on long
expeditions, leading two fine camels which they had brought with them,
carrying food and water, and bestriding their own fine animals. Allola's
sharp eyes regarded Mr. Hampton. She did not know why they made these
expeditions. Perhaps, he----

Mr. Hampton smiled a little at her curiosity. Then he turned to Ali and
the boys who were attentive listeners like himself.

"The Professor and Ben Hassim were scouting around the base of the
Shaitun Mountains," he said. "When he left me to come on in advance,
Souchard said he intended to put in his time prospecting the mountain
wall in both directions from the old stone road up which he had stumbled
into Korakum in the first place.

"You will remember that the men of Korakum told him the only way to gain
entrance to Athensi was along the course of the subterranean river
passing around the walls of Korakum. This river had its rise in the
heart of the mountains behind Athensi, passed through the valley in
which that city was situated, then disappeared again into the mountains
and after passing through a series of natural caves or tunnels
interspersed by open stretches of canyon, emerged into the plains of
Korakum. Then it dived into the outer ring of mountains, never to
reappear above ground. Probably, eventually, it reaches the Niger far to
the west of us.

"Well, it was my friend's belief, based on hints dropped by one member
of the exiled Athensians living in Korakum, that the heights above the
hidden city could be gained by another method. Very long ago, he
gathered, there had been another great road leading out from these
heights to the desert, but the Athensians had destroyed it in order to
preserve their isolation. It had been a great engineering feat to build
it, but they had ruthlessly destroyed bridges across chasms and stone
viaducts along the faces of steep cliffs, thus ensuring the
impregnability of their city. However, Souchard understood, although his
informant never would make a positive statement, that some of the exiles
had been busy patching up the gaps in this road, flinging rude rope
bridges across the chasms, and so on, to the end that men might pass
single file. Doubtless, this was for purposes of accomplishing a coup of
their own."

"And he was seeking that old road?" asked Jack.

"Yes," said Mr. Hampton. "And my guess is that, perhaps, he was
discovered at it, and was tracked here and disposed of, in order that
the secret might not escape."

"Wow," cried big Bob, letting a long breath escape. "Pretty mess we're
planning to go into. I thought this was going to be a gentlemanly
expedition, with overtures made to the Athensian rulers to let us come
in and study their habits and history."

"And here we are stepping into a hornet's nest," supplemented Frank.

Mr. Hampton smiled slightly.

"Professor Souchard gave me to believe that it would be possible to
approach the Athensians peaceably," he said. "Otherwise I would not have
undertaken this expedition, and brought you boys into danger, of course.
But I'm beginning to believe now that he exaggerated the ease of
approach, and minimized if he did not entirely ignore the dangers.
Remember, he knew nothing much of the real Athensians. The exiles living
in Korakum were his sole source of information. And, although he learned
their language enough to converse with them haltingly, so short was his
stay that there were many vital facts which he was unable to learn.

"I pointed this out to him," he added, "but he said that when we
arrived, we would stay at Korakum examining the ruins, which in
themselves are worth any scientists' time and study, and in the meantime
learn the Athensian language from the exiles and gain a good working
knowledge of the manners and customs of the people of the hidden city
and the interior plateaus.

"That, as you know, was to be our first step. Afterwards, we were to
proceed as our increased knowledge dictated. If it seemed the proper
thing to do, we planned to send an embassy to the Athensians, asking
permission to visit their city."

"Could it have been the exiles of Korakum, Dad, who were responsible for
this raid?" asked Jack.

Mr. Hampton shook his head.

"I do not believe so," he said. "Souchard described them as friendly to
him, and as you know they aided him to return to civilization. But
enough of that," he added. "Let us hear the rest of Allola's story." And
turning to Ali, who acted as interpreter, he asked him to bid the old
woman continue.

Nothing loth, for she relished being the center of attention and had
resented this conversation in a tongue she could not understand, Allola
described events on the day of the raid. "The Crazy One" and Ben Hassim
had been absent more than two weeks from the oasis, but as they had
stayed away equally long if not longer in the past, nobody worried. On
leaving they had taken food and water on their led camels sufficient for
a protracted stay, and it would not be necessary to feel anxiety about
them for at least another week.

In the morning, however, on looking at a calendar which "The Crazy One"
had given him and which was a source of much satisfaction, as he had
never before been able to keep track of the passage of days, Sheik
Abraham had noticed a black mark drawn around the date. Then he had
recalled that long before his friend had told him that on this day, the
thirtieth of the month, friends would arrive from the east.

"That's right," said Mr. Hampton, while the boys nodded. "We had
arranged with Professor Souchard to time ourselves so as to arrive on
this day. Leaving Khartum on such and such a day, if all went well, we
would spend so many days in desert travel and reach the oasis on the
thirtieth."

Allola proceeded. Noting the date and recalling "The Crazy One's" words,
the Sheik Abraham had told the tribesmen to keep a sharp look out across
the southern desert, for the return of him and Ben Hassim. All day the
men and women, working about the oasis, in their little farm patches or
grinding oil, had paused now and again to glance to the south.

Not until late in the afternoon, however, had they descried the
looked-for figures approaching. They had gone out a little way into the
desert to welcome them, and it had been a triumphal procession homeward.
Everybody had crowded around to hear the tale of "The Crazy One's"
latest wanderings, as explained by the merry Ben Hassim, and it had not
been dreamed necessary to keep watch. No watch ever was kept, anyway, as
the tribe had no enemies and few, indeed, were the travellers who came
this way.

Suddenly, a body of white men, strangely-clad (like that other, said
Allola, nodding toward the tent within which lay the wounded Athensian)
and mounted on swift camels, dashed into the midst of the encampment.
They bore short heavy swords and lances, but made no effort to harm
anyone.

In number they were, perhaps, two score. Dividing, they encircled the
enclosure where the whole tribe was gathered. The dozen men and the
score of half grown boys of the tribe, caught without arms, were
helpless to resist. All were made prisoner, the Sheik Abraham was
dragged from his tent where he was conversing with "The Crazy One." The
women were brought forth. Only "The Crazy One," rolling quickly beneath
the wall of the Sheik Abraham's tent, managed for the moment to escape.
Allola saw him from her retreat beneath the Sheik Abraham's divan, where
she had thrown herself. She was overlooked.

"Then I heard his voice screaming into the devil machine," said Allola.
"And I knew he had fled to his tent and was calling upon his gods for
protection. The strangers heard, too, and pursued and caught him. There
was a fight. I heard, but I could not see. I lay hidden then until you
came."

Mr. Hampton looked thoughtful. "That explains some things," he said.
"Professor Souchard hurrying to get back to meet us was tracked by
Athensians. Probably he had aroused some watcher's suspicions on an
earlier scouting expedition along their mountain wall, and when he
appeared this time a war party was summoned. Before it could arrive,
unconscious of his impending fate, he had departed. But his trail across
the desert was followed, the war party pushed its animals and, although
he may have had a whole day's start, they caught up with him an hour
after his arrival at the oasis. He was cut down as he called for help."

Jack groaned. "Poor old Professor. If only we had been here. Our party,
with guns, could have put the Athensians to flight in a twinkling."

"Well, boys, that's all for the time being," said Mr. Hampton, at
length, after some further discussion. "When we buried Professor
Souchard and Ben Hassim, as you will recall, there was no mark of
bullet. They had been garroted, their necks broken, in the fashion of
the Hindu Thugs. Now Allola says she saw no guns among the Athensians.
These two circumstances would seem to indicate they are without
firearms. Nevertheless, I cannot believe that a people, keeping up an
annual contact with the outside world, would be without knowledge of
firearms. Besides, those of the tribesmen were taken, for there isn't
one in the oasis. Would they have taken guns without knowing their use?
No, they might have suspected they were weapons and have smashed them,
but they wouldn't have carried them away. Then, too, there is this
matter of carrying off the whole tribe of Sheik Abraham. What was the
reason for that?"

"Probably the raiders planned to use them as slaves," said Ali, to whom
the dark secrets of the slave-raiders who still practice their trade in
many places in the heart of the Dark Continent from the Abyssinian
borders on the east to the Niger and Kongo territory, were not unknown.

"Perhaps," said Mr. Hampton, slowly. "If the tribesmen were to be used
as slaves, that would indicate why their lives were spared. But it is
also possibly the Athensians suspected Professor Souchard might have
imparted information regarding their country, and they were taking no
chances on leaving any witness against them behind."




                              CHAPTER VI.
                     THE TALE OF THE SLAVE TRADER.


Days succeeded during which the party marked time. Mr. Hampton was
resolved to take no further steps until first having a talk with the
wounded Athensian. He was showing signs of recovery, and was being fed
broth at intervals, but was delirious. Should he return to his senses,
Mr. Hampton planned to question him in his own tongue. From Professor
Souchard he had acquired an elementary vocabulary in that language as
taught the latter by the Athensian exiles in Korakum.

In the meantime, after exhausting the possibilities of the oasis and its
small vegetable farms and flocks of sheep and goats, which had been left
behind by the raiders, the boys found time hanging pretty heavy on their
hands.

Frank had more to occupy him than his comrades, as he was intent on
making good on his boast that the radio station could be repaired.
Almost every waking hour he spent in this occupation.

Ali's stories of African life helped somewhat to while away the time for
all. This swarthy-cheeked, hawk-nosed Arab had poked his nose into every
corner of northern Africa. And, when one considers that the Sahara
Desert alone is more than 3,250,000 square miles in extent, or the size
of all of the continent of Europe, that meant Ali had done a lot of
poking. He was intimately acquainted with the life of every
Mediterranean city from Tangiers and Morocco to Port Said. He had
crossed the desert by every camel route. He knew the great mountain of
Asben in the middle of the Sahara. He had travelled to Timbuktu. He had
penetrated to Lake Schad and the sources of the Nile, and had voyaged on
the Niger. In a word, Ali was a mine of information on northern Africa.

Putting two and two together, he was able even to say he had heard of
the Athensians before the Professor brought their existence to his
attention. Not that he heard of them by that name, however. He told
about it at the camp fire one night, while Jack threw on the blaze
several handsful of dried coarse grass and the light leaped high,
bringing out the curious faces of the boys and Mr. Hampton and the
impassive features of the Arabs.

It was from another Arab, a slave trader who had been to Gao, that Ali
had the tale. This man Ali encountered at a desert oasis one night. It
had been years before.

"We were the first travellers who had visited that oasis in a long
time," said Ali. "Some of these isolated oasis are the homes of robbers
who raid caravans. But like Sheik Abraham, this sheik was a harmless and
pleasant old fellow. He made us feel welcome. We sat on little grass
mats on each side of him in front of his tent. Before us was a blazing
fire on which his favorite wife now and then, would throw a stick of
wood or some grass. She was young, veiled, and her hands were
elaborately tattooed. Silver bracelets and ankle-rings jingled at every
step. Yes, evidently she was the old patriarch's favorite wife.

"It was very pleasant sitting there, and the woman brought us bowls of
_kous-kous-soo_ and tiny brass cups of sweet Moorish coffee on a tray.
After eating, we lighted cigarettes and began to talk. We felt it was
our duty to tell strange stories of our adventures in order to repay our
host's courtesies. He was a man who did not travel, and it was our duty
to entertain."

All paused a long time, staring impassively into the fire. At length he
resumed:

"Well, the talk passed from this to that, and presently this slave
trader began to tell of a strange people from whom every year came to
the slave marts of Gao a delegation seeking strong men.

"'With them,' he said, 'comes a man who can speak to Frenchman, Arab,
Berber, Tuareg, all the peoples of the desert, in his own tongue, a man
who speaks many Negro dialects, too. He is the leader. There are two
minor chieftains and a guard of two score men armed with short swords,
lances and Arab rifles. The rifles have very long barrels and much
silver work on the stocks. They are worth a great deal of money.

"'On the outskirts of Gao this party encamps, while a picked force of
ten warriors accompanies the three leaders into the slave bazaars. As
you know, we dealers traffic in all sorts of human cattle. We have
Negroes from many different tribes, captured in battle and sold us by
the victors. Arabs, Tuaregs, Berbers, also come to us from those who
have captured them in the fight. Even white men, Frenchmen and
Spaniards, captured in Morocco and Algiers and Tripoli by fierce
tribesmen, like the Riff tribes who are forever fighting the Spaniards
in the Atlas mountains, reach us for sale into slavery--'"

"Oh, come, now, Ali," interrupted Mr. Hampton, good-naturedly, "that's a
bit too thick."

Ali shrugged. "Many things go on in Africa which the whites cannot
stop," he said, simply. "It is true, this I tell you."

"But white men," protested Mr. Hampton.

"What think you, then, becomes of the men taken prisoner from the French
and Spanish and Italian foreign legions when detachments are trapped in
the desert?" asked Ali. "They are not butchered. No, they are too
valuable. Some desert sheik or the kaid of some desert city buys them
for slaves."

"All right," said Mr. Hampton. "Go on."

He was quite convinced, yet he knew enough of the mystery of this vast
land to many parts of which white men never even had penetrated to this
day, to realize what Ali described was not impossible.

"'Then,' said this slave trader," continued Ali, "'these strangers
select the very strongest and youngest of the men, be they white, black
or brown. Unless a man is of exceptional strength he is not chosen.
Sometimes they select only two or three, sometimes a dozen.

"'Only once have I been at Gao when these strangers appeared. Much had I
heard about them. My curiosity was excited. That time I had among my
slaves a very strong man, a man of the Kongs. He was a full six feet
tall, beautifully proportioned, with a fine intelligent head and a brown
body like mahogany. He was only twenty-one.

"'The leader of the strangers came to me and pointed out this man. He
spoke in Arabic. He wanted to know the Kong's antecedents, and I said he
had been taken in battle only after he had slain five Bakus, being
finally entrapped in a net thrown over his head and arms.

"'He took the Kong without even asking my price, which was high. As he
turned to go, I said on the impulse, "Whence come you?" He stared at me
haughtily. For a moment I thought either he would not answer or else
would order his guards to cut me down. Then he laughed, a wild, reckless
laugh. My blood chilled. "I come from the country of the past and of the
future," said he. Then he was gone.

"'I made inquiries. But from none could I learn more than I have told.
Slave traders come and go. Within the memory of the oldest of us,
reaching back fifteen or twenty years, this stranger had come once each
year to the slave marts. For how long before that he had come, I do not
know. None ever had pursued him into the east, to see whence he came.
That is all.'

"So," concluded Ali, "I have since been thinking. That man was a big
chief among the Athensians, if not the greatest leader himself. Who he
is, how he has acquired a knowledge of many languages, I do not know.
That he and his people are white, of course, is not so marvellous, as
the Berbers and Arabs are white races, and so are the Kabyles who
inhabit the mountains of Morocco."

Mr. Hampton nodded. "An offshoot of the white race which has maintained
a splendid isolation in those mountains south of us, undoubtedly. Yet
how this leader acquired his knowledge of civilization puzzles me. And
why, Ali, are these annual expeditions to Gao made? And only the
strongest slaves selected?"

Ali shrugged. "It is for Allah to say," he replied, and lapsed into
silence. Evidently, for that night, the loquacious Ali had said all he
intended to say.

His story, however, furnished Mr. Hampton with food for reflection and
on several occasions he discussed the matter with the boys. Especially,
did he note that the slave trader's account, as repeated by Ali,
betrayed that the Athensians possessed rifles. This made them more
dangerous enemies.

"In fact, boys," he concluded, one day, after a lengthy discussion, "I
have become pretty firmly convinced that these Athensians cannot be
peacefully approached as had been our original intention. Therefore, we
shall have to abandon the expedition. I shall wait a few days more to
see whether this man recovers sufficiently to be moved, and then, if we
can gain nothing from him in response to questioning, we shall set out
to return."

"What," cried Jack in dismay, "leave without attempting to learn what we
came all this way to discover?"

His father nodded gravely. "Professor Souchard and Ben Hassim have been
slain," he said. "Sheik Abraham and all his tribe have been carried into
slavery. Quite evidently, the Athensians want no intruders and we would
only imperil our lives by pursuing our investigations further."

"But what'll you do, Dad?"

"I shall lay the matter before the French and British governments. Now
that the Great War is over, it may receive attention. They can send
embassies, supported with sufficient power to compel recognition. Then,
it is possible, the Athensians will yield on being shown no menace to
their freedom threatens, and may admit scientists to their mountains to
study the ruins of Korakum and the library of Athensi, if such really
exists."

"Dad," asked Jack, after a pause, "I know I've spoken of this before,
but I can't get it out of my mind. Isn't it possible the Professor may
have been deluded, that all he told you was a creation of fancy?"

"No, there was this raid on the oasis, the description of the raiders,
this wounded captive, and Ali's story of the annual visit of the
Athensians to the slave marts of Gao."

"Granted all that," Jack stubbornly objected, "yet it does seem nothing
short of miraculous that a city such as Athensi should exist unknown to
the rest of the world."

"Well, but, Jack," interrupted Bob, while Mr. Hampton approvingly
nodded, "look at Llassa, the Secret City of Thibet. Only one white man
has ever penetrated it and lived to tell the tale. And that is in the
heart of Asia, the oldest continent known to civilization, while here is
Athensi in the heart of a continent which is still in many parts
unexplored."

Jack threw up his hands in token of surrender. "All right, old thing,"
he said. "I'm just as keen as you to carry this through, and I was just
arguing. I do wish father would continue with it, but I suppose his plan
is the best."




                              CHAPTER VII.
                           CHASING OSTRICHES.


"Ali, come here. Take a look through these glasses and tell me what you
see," called big Bob early one morning.

As he spoke he was approaching the encampment, where the Arabs were
preparing breakfast, at a run.

Ali looked up inquiringly, and Bob grasped him by an arm and urged him
forward, past the well, through the patches of garden stuff, down among
a grove of fig trees, to the edge of the oasis. They were facing
eastward, and the sun which had not been up long cast a dazzling
radiance over the sand dunes. These latter lay scattered
indiscriminately, like the waves in a choppy sea--great bare swellings
of sand, with here and there low stunted clumps of bush.

At first, gazing into the path of the sun, Ali could descry nothing, but
under Bob's direction he finally located what had attracted the other's
attention. This was a number of dark black objects seeming like bushes
in motion. But Ali's better-trained desert eye solved what had merely
been a puzzle to Bob, and without taking the glasses from his eyes he
exclaimed

"Ostriches."

"Ostriches?" Big Bob could hardly believe he had heard aright. "Why, you
don't find ostriches here, do you? I thought the only ones left in
Africa were the domesticated ones on South African farms."

Ali smiled.

"They run wild in the waste places and on the desert," he said.

"Great Scott," cried Bob, in high excitement, a sudden thought striking
him. "Can't we break the monotony by having an ostrich hunt? Even if we
don't catch any, it'll be fun."

"To hunt those birds we should have horses," said Ali, dubiously. "They
run very swift. With horses, the hunters pursue them in a great circle,
relays of horsemen relieving the tired ones."

"But won't camels do?" Bob was eager to put his scheme into effect and
an appealing note crept into his voice which caused the kind-hearted Ali
to smile.

"We can try," he said. "Only you must not be too disappointed, if you
see them run away from you."

"All right," promised Bob. "I won't. Come on, let's tell everybody,"

They hurried back to the encampment and Bob's bellow quickly caused the
others to assemble. Then the news was told. It aroused less enthusiasm
than Bob had looked for. None of the Arabs was keen, to go, believing
that with camels it would be next to impossible to run any ostrich to
ground. Besides, what would they stand to profit? Ostrich meat is tough,
stringy and practically inedible. The great bird's sole good to man is
to provide feathers for women's adornment. As for Frank, he planned to
put the finishing touches to the restored radio set and could not be
turned aside from his project. Mr. Hampton intended to stick by his
patient who was beginning to mutter in his delirium. Most of his
mutterings were in Athensian, which Mr. Hampton could recognize as such
but which was meaningless to him. But in the midst of Athensian words,
he believed he could distinguish an occasional French word, and this
puzzled and interested him.

"Well," said Bob, disappointed, "if nobody else goes, Ali and I will go
it alone."

Jack grinned. "Count me in, old thing," he said. "I'm as keen as you for
a little excitement. Only thing is, I hate to ride those dratted camels.
But what must be, must be. Let's go."

Three camels were brought up, accordingly, and saddled, and then Ali,
Bob and Jack mounted and ambled away. Mr. Hampton accompanied them to
the edge of the desert, warning them to look out that they did not come
to close quarters with an infuriated ostrich, especially if by any
chance they were unarmed.

"These African ostriches stand seven or eight feet tall, boys," he
warned, "and they have tricky tempers. If by any chance you become
dismounted and an ostrich charges, throw yourself flat on the sand and
stay there. Then the ostrich can't kick you. He'll probably sit on you,
but hold your position until one of your comrades can come up and shoot
him. Remember, the ostrich kicks forward or sidewise, and a blow from
his powerful leg can cave in a man's head or break a horse's leg."

"All right, Dad, we'll be careful," promised Jack, "but it's hardly
likely we'll ever get to close quarters. I imagine when the ostriches
see us coming, they'll give a flirt of their tails and sail away."

During the time taken for saddling up and getting started, the ostrich
herd had moved eastward and now was out of sight, even through the
glasses. Ali led for the place where they had been seen, and as they
rode gave the boys a little homily on the great birds they hoped soon to
stalk.

Ostriches are found throughout Africa, except in the central and coastal
regions of great forests. Especially do they haunt the waste places and
deserts, where stunted bushes furnish sufficient food for their needs.
Their hardihood and fleetness makes life possible where other animals
could not exist. Even sand and pebbles apparently can be digested by
them, and it is a fact that the domesticated ostriches of farms and zoos
have been known to swallow glass, barbed wire, bright-colored bits of
metal, bed springs, and other similar objects.

Unfit for food, these great birds are valued because of their beautiful
feathers, which can be plucked at certain seasons of the year without
harm to them. For this reason, the Arabs of northern Africa and the
colonists of South Africa for long have domesticated ostriches. In South
Africa alone, latest estimates were that the number of domestic
ostriches was between 800,000 and 900,000. Ostrich-raising also has been
introduced into California and Arizona with varying success. One of the
chief worries of the ostrich raiser is proper incubation of the eggs,
which take at least forty days to hatch and more frequently a full seven
weeks.

In their wild state, the ostriches lay their nests of great eggs--ivory
white in color among the birds of the Sahara, mottled among those of
Basutoland and South Africa--on the top of a sand dune, whence they can
see in all directions and guard against surprise. The male takes his
turn with the female in sitting on the nest. Jackals, drawn by the
chance of obtaining some of these eggs, almost invariably haunt the
ostriches. When an unguarded nest is found, the jackal pushes a big egg
up the sand slope with his nose and then lets it roll down into the
nest. Coming into contact with another egg, usually both become cracked.
Then the jackal sucks the contents. There is so little on the desert to
feed the jackal that the dangers he runs from the attack of an
infuriated ostrich are braved in order to obtain such a succulent feast.
Observers have reported seeing a jackal pursued by an ostrich and
running in zigzag fashion for his burrow. If he fails to reach it in
time, one swipe of the ostrich's leg tosses him yards away and
disembowels him.

When the desert people conduct an ostrich hunt, it is for the purpose of
capturing birds to be incorporated into their herds. They go out in
numbers on fleet horses, circle widely to fixed stations, and the chase
begins. The fleeing ostrich for a time can outrun the swiftest horse.
Therefore, the pursuer keeps going until his horse lags, whereupon he
gives way to another horseman. A desert creature, strangely enough the
ostrich is not inured to great heat, and sometimes when being pursued
under a hot sun will suddenly keel over, dead of apoplexy.

Some of the above Ali explained to the boys as they lurched forward on
camel-back. It was not their intention to kill an ostrich, but, if
possible, to capture one. For this purpose, Ali had provided lengths of
rope, weighted at each end, which if well cast would wrap around the
legs of an ostrich and bring it down. Bags to be clapped over the head
also had been provided. Ali smiled discreetly to himself, however,
realizing that on camel-back and without practise, it was next to
impossible that either Jack or Bob would succeed in bagging an ostrich.

The latter pair, however, while resolved to do their best, given the
opportunity, were under no illusion, either. They did not count on
capturing an ostrich. What they sought was a closer view of them, a
chase and the attendant excitement. That would repay them for the trip,
would provide a welcome break in the dullness of their days.

Before leaving, each had taken with him a small radio receiving set,
fastened in the crown of the solar topee or sun hat. It differed
materially from the set Frank had borne on camel back as they approached
the oasis, and over which they had received Professor Souchard's last
message. This set was built on a small panel fastened on the inside of
the sun helmet. To use it, it would be necessary to halt and set up an
aerial and bury a ground. The ground, a small mass of zinc, was carried
slung to Bob's saddle, and the aerial--seventy-five feet of thin wire,
hung coiled in the same place. A pair of jointed steel rods, of special
construction, both light and durable, was strapped to his rifle
scabbard. Before returning, it was planned to set up the aerial, and
test whether Frank had succeeded in repairing the Professor's sending
station.

Presently, surmounting a sand dune slightly in advance of the others,
while Bob and Jack still struggled up its sliding slopes, Ali placing
the glasses to his eyes saw the ostriches due east and about a mile and
a half away. He dropped back at once, cautioning the boys to stay beside
him rather than surmount the dune.

"Ostriches have very good sight, and almost as good hearing," he
explained. "I will stay here, and do you two work to right and left of
me under shelter of these sand dunes until you judge we have the herd
encircled. Then I'll approach and start them. You keep your stations
until I turn over the chase to one or other of you. The ostriches will
run in a wide circle."

"All right," said Bob. "I'm off." And he started away to the left.

With a wave of the hand, Jack set out to the right, little dreaming of
the momentous events to occur before he saw Bob again.




                             CHAPTER VIII.
                       BOB'S FIGHT AGAINST ODDS.


As Bob rode along on camel-back in the lee of the sand dunes, there was
never a thought of danger in his mind. The Sahara is not like the great
grassy steppes of Siberia or the plains of western America, which are
flat and level as a table top and across which one can see for miles in
every direction. On the contrary, this great African desert is filled
with shifting sand dunes, low hills of sand, which are whipped away when
the strong winds blow and change their position, piling up in new
drifts.

In appearance it was now to Bob's eye like the sea when waves were
kicking up. In the trough of these sandy waves he made his way forward,
exercising care in advancing from the shelter of one dune to another to
keep below the crests.

It was lonesome riding, under the baking sun, in that land of stillness,
without sign nor sound of any human being. He had an eerie feeling, as
if something were about to happen. But he shook this off, and laughed at
himself. Merely a touch of nerves, he thought, due to the loneliness of
the surroundings.

Before setting out, it had been decided he and Jack would have to ride a
good half hour away from their starting point, from the place where Ali
was posted, before they would be in the proper position. Therefore,
looking at his watch now and again, he kept on without exposing himself
to gain sight of the ostrich herd, until the full half hour had elapsed.
It seemed to him a much longer time, and if it had not been for his
watch he would have been tempted several times to clamber up a sand dune
and look around.

When at length, the allotted time having elapsed, he did urge his camel
up the top of the nearest sand dune, there was no sign either of
ostriches or of his companions. Far in the distance could be seen the
tops of the palm trees of the oasis, dwarfed and beautiful as a painting
against the blue sky. All else was hidden from his sight.

"Shucks," thought Bob, "in dodging to keep below the tops of the sand
hills, I must have gotten off my course."

That, in reality, was what had occurred. Instead of the small circle he
had planned to make, which would have put him on the point of an arc a
third of the way around the herd from Ali's station, he had borne off
the course gradually but surely in his attempts to remain hidden.
Moreover, he had gotten into a region of larger sand dunes, so big they
amounted to low hills.

"Who knows," he grumbled aloud, wanting to hear his own voice for the
sense of oppression had grown stronger, "who knows, the ostriches may be
over the next dune or so, and I just can't see them from here. Well,
there's the oasis, and I can make for it if worse comes to worse. But
I'd feel like a jackass to go back and say I went and got myself lost."

As he spoke he was swinging the glasses slowly over the surrounding
country.

"Confound the luck," he grumbled again, when unrewarded, "believe I'll
fire a shot or two. If Ali or Jack hears, he'll answer."

Unlimbering his repeating rifle, he threw it to his shoulder, aiming for
the crest of a nearby sand dune, and pressed the trigger. The report
followed, and a spurt of sand showed the accuracy of his aim. Again he
pressed the trigger. But this time the gun failed to be discharged.

In surprise, Bob bent down to examine it. What could be the matter?
Evidently, the mechanism had become jammed. Must have forgotten to clean
it, and, perhaps, the all-pervasive desert sand had clogged it. A pretty
note, he thought, and experienced a momentary feeling of panic. What if
it had happened at a time when he needed it to protect his life? The
thought made him shudder, and glance around quickly.

Then a sight met his eyes at which words failed him. For a moment, he
sat as if paralyzed, unable to move or even to think.

Ten horsemen had filed silently, soundlessly, from behind the shoulder
of the sand dunes in his rear. They were already almost upon him. From
momentary paralysis, Bob's mind leaped into lightning-like activity. He
saw his escape toward Ali and Jack was cut off on one side, and on the
other his retreat toward the oasis.

It would be useless to attempt to flee, for his camel soon would be
overtaken by the swifter horses, if he were not shot down in the
meantime. For that first swift appraising glance assured him these men
were armed with long Arab rifles.

In the same glance, he noted something else which made his heart skip a
beat. These men, tanned though they were, were recognizable as white
men. And they were dressed exactly as was the wounded Athensian, lying
delirious at the oasis, in fact they were Athensians, in short toga-like
garments, bare legs and soft leather moccasins.

All these observations and thoughts passed through Bob's mind in a
moment. He had a wild idea of throwing himself from his camel, causing
the latter to kneel, and from behind it, as from behind a bulwark,
fighting off the attackers. For, that they intended harm to him, Bob
felt assured. But even in the moment of leaping from the saddle, he
realized the futility of such procedure. His rifle was out of
commission.

What should he do? The party was closing in. Bob gave one wild searching
glance to the south, where he had left Ali and Jack. They were nowhere
in sight. Neither, for that matter, were the ostriches.

Under other circumstances, Bob would have made a fight for his liberty
with his bare hands. Those of our readers who have followed his career
under other skies know well what a superb wrestler is Bob. And with the
additional weight and strength of an added year or two, Bob was now a
wrestler and boxer second to none. But even as the thought of grappling
with the leader entered his head, he saw by the loosening of rifles in
the hands of others that his first movement would bring a swarm of
bullets his way.

Or would they shoot? A new idea came to Bob. In this still desert air,
the sound of shots would carry far. If his one lone shot of a minute
before were to be succeeded by a volley, Ali and Jack would take alarm,
and perhaps even back at the oasis the alarm would be given. This party
consisted only of ten men. Perhaps, they preferred moving soundlessly
rather than run the risk of bringing a party of equal strength upon
them. Perhaps, they would not use their rifles at first, should he
attack their leader, expecting to see him overcome. Well, if they only
withheld their fire until he could grasp the rascal and seize his rifle,
Bob wouldn't care. With a weapon in his hand, he could go down fighting.
What a fool he was, anyway, to have left the oasis without his
automatic.

One phase of the situation which Bob did not take into account was that,
even if Ali and Jack managed to discover his predicament and either came
to his rescue themselves or set out to rouse the oasis, the attacking
party could escape because of the greater swiftness of their horses as
compared to camels.

Instead, as the leader of the attackers approached--a strikingly
handsome young man, with a round firm face, hawklike nose and crisping
brown hair, Bob set himself for a flying leap from the camel. The leader
rode slightly in advance of the others, who mounted the sliding sand
hill in a semicircle behind him, toward Bob sitting his camel on the top
of the hill. Then an astonishing thing happened.

"_Attendez, monsieur_," called the leader, in French. "It will be
useless to resist."

Now Bob had studied French. In fact, he could manage a conversation both
in French and Spanish, although somewhat better in the latter language
because of the opportunities he had to learn it at first hand when in
South America, as narrated in "The Radio Boys Search for the Inca
Treasure." But hearing French from the lips of this Athensian almost
bowled him from his seat in surprise.

Yet Bob was not so certain of the folly of resistance. He believed he
had weighed the situation, and he was willing to take a chance. He was
sitting his camel sidewise to the approaching party. The off leg he had
slowly brought up to the point where a quick fling would free it of the
saddle. Pressing his left foot down hard into the awkward stirrup, he
suddenly gave a spring upward and outward. At the same time he brought
his right leg over the saddle. Forward he launched, as if shot from a
catapult. His one hundred and ninety pounds of bone and muscle struck
the young Athensian on the shoulder with irresistible force, as Bob
hurtled the five-foot gap separating them.

Simultaneously, the big fellow sent his useless rifle crashing into the
face of the nearest Athensian rider to the rear and slightly to the
right side of the leader. The latter was knocked out of his saddle.

Bob's arms went out as he struck the body of the leader, and they closed
convulsively about him. Thus, as the young Athensian was hurled from his
saddle by the force of the blow, Bob was dragged along. He fell on top
of his victim, knocking all the fight out of him. The other lay still
and inert.

A bit dazed himself, but with his wits still about him, Bob scrambled to
his feet as the frightened horse of the Athensian leader dashed wildly
into a rider approaching from the left. In a twinkling there was a
pretty mix-up of horsemen, shouts and shrill screams. But in his primary
object, which was to possess himself of the leader's rifle, Bob had
failed. The weapon had been tossed some distance away in the impact, and
as he gazed around him it could not be seen.

Three or four horsemen were in a tangle where the bolting animal had
created panic, and evidently were devoting their attention not alone to
regaining control of their own mounts but also to securing the runaway.
Another man lay writhing on the ground, where he had been knocked by the
force of Bob's rifle flung into his face. The leader lay at Bob's feet.

But four horsemen still remained clear of entanglements, and they were
closing in on Bob on three sides. He would have to act quickly. What was
to be done? Retreat to the summit and attempt to regain the saddle of
his camel, which over his shoulder he could see standing immovable
despite all the commotion? No, too awkward to get back on that clumsy
beast, and besides he could not outdistance the pursuers.

Now, if he only had a horse. Quickly as thought, Bob with a tremendous
tensing of his leg muscles beneath him, and gathering up his flowing
burnoose about his waist, leaped a full five feet in the air, as the
nearest of the approaching horsemen came broadside on and reached out to
clutch his hair. The meaning of the man's movement did not escape Bob,
even in this crisis. Evidently, he was to be taken prisoner, but he was
not to be killed. Otherwise a shot could quite easily have ended the
fight.

Bob's leap disconcerted the other, and Bob's arms, closing about his
waist from the rear, almost pulled him from the saddle. But the
Athensian clung desperately, knees gripping tight and one hand clinging
to the high horn of the saddle, and thus, as the horse leaped ahead in
fright, the Athensian retained his seat while Bob pulled himself up
behind him.

"Whoop-ee," yelled Bob, enjoying himself to the full, and taking an
animal delight in the fight. The blood in his veins sang in exultation.
The heady wine of success against odds had intoxicated him.

Now to turn the horse for the oasis and flee, with his captive.

The next moment a crashing blow descended on his head from the rear, and
he pitched forward against the Athensian. In a unconquerable haze
against which he fought but without success, he felt himself falling,
and then felt strong arms encircle him from the side and lower him to
the ground. The next moment he lost consciousness.




                              CHAPTER IX.
                          A PUZZLING PROPHECY.


For a long time before regaining full consciousness, Bob was confusedly
aware of pain. He had nightmare impressions, the sort of feelings one
experiences in a dream when undergoing frightful experiences from which
he is unable to free himself. To Bob it was as if he lay on a torture
wrack, arms and legs pinioned, and head held in a vise. Try as he would
to reach up a hand to free his head of the oppression it was impossible
to do so. The stars seemed to whirl around him, each with the face of an
Athensian, mocking him, while a red devil in a filmy cloud who seemed to
bear a striking resemblance to the fallen Athensian leader hovered just
above the tip of his nose, laughing at him.

All around the edges of his world--this world of pain of which he was
the center--lay a thick cloud which his vision could not pierce. In it
came and went the Athensian-faced stars.

Once he struggled back to full consciousness. His eyes opened and he was
able to note his surroundings. Then he saw that he was bound to the
saddle of his camel, lying forward, almost on his chest. His hands and
feet were tied, and many lashings around his body prevented him from
slipping off. He even was able to note that the lashings consisted of
the rope lassoo with weighted ends with which he had planned to bring
down an ostrich, supplemented by the coil of wire for aerial and ground,
which had hung looped to his saddle.

On his head was his solar hat or sun helmet, at which he wondered
dazedly. Evidently, the blow which had felled him had been broken by the
helmet. Perhaps, even, it had fallen on the jutting rear brim, and thus
had not crushed against his skull the little radio receiving set
cunningly inserted in the crown so that to a casual glance it seemed
merely a part of the helmet. If so----

But then consciousness failed, and Bob sank again into the nightmare of
the wrack and the torture.

When again he was restored to consciousness, the rope and wire bindings
holding him in the saddle had been loosed and strong hands were lifting
him to the ground, which was no great distance away as the camel had
been compelled to lie down.

As his feet touched the ground, Bob attempted to stand, but his legs
buckled under him and he would have fallen were it not for the hands
beneath his armpits. He was lowered to the ground, and lay there with
eyes closed while those who had assisted him moved away. He could hear
the soft swish of their moccasined feet in the sand.

Cautiously, when he believed himself alone, Bob opened his eyes and
found himself staring up in the crown of his sun helmet, which had been
placed on his face. Yes, the blow had not wrecked the little radio set,
which he could see in the crown. At least, he could discern the panel on
which the instruments were placed, and which formed the bottom of the
set. The blow had fallen on the rear brim, which was crushed and
splintered.

Bob still felt excruciating pain on the back of his head, but came to
the conclusion that the softening of the blow had saved him from a
crushed skull and that in a day or two he would be all right.

Through this hole in the brim, resting on the tip of his nose, he could
see a portion of his surroundings. The light was fading. Evidently,
twilight had come. Bob wondered at that, which meant he had been riding
all, or at least the better part of, the day.

A halt had been called, and in the line of his vision Bob could see a
fire just beginning to blaze, and the bare legs of men coming and going
about it. There were no tents, and Bob's first conclusion, namely that
they had halted at an encampment of other Athensians, evidently was
incorrect. The few figures, and the absence of such noises as would
attend a large camp, were assurance that no additions had been made to
the party.

Speculation as to what would be his fate took possession of Bob, as he
again closed his eyes to ease the pain behind them. That he had been
captured for a purpose was apparent. Otherwise, when he had put up his
heroic fight, he would have been killed. Well, at least he was to be let
live; for a while, anyhow. That was something. While there was life, he
told himself, there was no need to despair.

Bob wondered what had become of Jack and Ali. Were they aware of his
predicament? Had they seen him captured and carried away, and would Mr.
Hampton set out to rescue him? Or was his fate unknown, and the outcome
of his adventure dependant solely on his own exertions? Would Mr.
Hampton give him up for lost and eventually carry out his plan to
abandon the expedition and return to civilization?

All these questions and many more passed through Bob's brain as he lay
there on the ground, while the blood slowly worked its way through his
cramped limbs and he felt every minute a return of strength and even
noted a diminution of the pain in his head. He was thankful that, at
least, he had not been incapacitated physically, that apparently his
strength and the use of his body was left him. When the time came for a
break for freedom, he told himself grimly, he'd show these Athensians.

At that moment, through the hole in the brim of his sun helmet, just as
he again opened his eyes, he saw the legs of a man approaching. Then a
hand grasped him by an arm and shook him, and the hat was lifted from
his eyes. Bending over him was an Athensian, a sturdy, stockily built
fellow, who jerked at his arm and indicated by signs that he was to rise
to his feet.

Bob struggled to comply, pretending to greater weakness than really
possessed him. He figured that if he appeared to be in a weaker state
than was the case, his chances for escape would be increased.

The man passed an arm around Bob and placed one of Bob's arms over his
shoulders, and then walked him the few steps toward the fire. The other
Athensians were seated about it, among them Bob noted with a grim
reflection of satisfaction one with his face almost entirely obscured by
a bandage. That must be the fellow who had felt the weight of his rifle,
and had, in fact, been bowled from his saddle by it. To their rear,
among a patch of stunted bush, were hobbled the horses. The leader, the
one whom Bob had leaped upon in his jump from camelback, sat a little
withdrawn from the others, leaning against a saddle.

Bob was led to him, and with a word in an unknown tongue the leader
dismissed the Athensian who bowed profoundly and withdrew.

"Sit down," commanded the leader, again employing French, and indicating
a spot at his feet.

Bob complied. For several moments there was silence, while both young
men studied each other. Bob's first thought was that this Athensian was
little older than himself, a man of perhaps twenty-three or twenty-four.
Bob was twenty-one.

In appearance, the Athensian had a pleasing face. His eyes, bright blue,
twinkled. The bold hawklike nose gave him an air of command, even of
nobility. It was hard to judge from the seated figure, but Bob's surmise
was that the other was over the middle height, probably five feet nine
or ten.

In his eyes was an expression of satisfaction as the Athensian ran his
glance over Bob's figure, and the first words uttered by either was his
sudden remark, shot at Bob:

"Monsieur is very strong."

Sounded as if he were going to be a good sport about that leap upon him,
thought Bob, and he grinned.

"Did I muss you up much?" he asked in his best French, in reply.
"Nothing personal, you know. I was fighting for my life."

The Athensian nodded.

"Two ribs were broken when monsieur fell on me," he said.

"Say, that's pretty tough," commiserated Bob. "Makes it hard for you
when riding, doesn't it?"

A shrug of the shoulders was the other's sole reply, while he continued
to stare at Bob.

"Monsieur is, perhaps, an athlete, yes?" he asked, with rising
inflection. "He participates in college sports?"

Mighty chummy of him, thought Bob.

"Oh, a little," he said.

"Monsieur is too modest," the Athensian said suavely. "Doubtless, he is
a great man among the youth of his land. Is it England? Monsieur is not
French nor Spanish. Then he must be English. I have heard the English
are fine sportsmen."

"Huh," blurted Bob. "I'm an American. In our country we have as good
sports as in England."

"An American?" queried the Athensian, in a tone of enlightenment. "Then
how comes monsieur in this far country?"

Bob did not reply. What could he say? He was puzzled by the Athensian's
attitude? Asking him about sports first, and then demanding how he came
to be here in the Sahara. Besides, how did this Athensian happen to be
speaking French, when he lived in a hidden city unknown to the world?
Bob decided it would not come amiss for him to ask a question or two by
way of continuing the conversation. So he smiled at the other, and said:

"How do I happen to be here?" With a laugh: "Oh, just hunting ostriches
when you bagged me. What was the meaning of that, anyway? You don't look
like a robber. And how is it you speak French so well?"

The Athensian bent a stern gaze on Bob. The twinkle died out of his
eyes.

"Monsieur was not merely hunting ostriches," he said. "Yes, perhaps, at
the moment. But he came here to meet a scientific man who had blundered
upon the secret of those mountains, _ne c'est pas_? Is it not so?" With
a quick wave of his hand he indicated the Shaitun Mountains on the
southern horizon, just dimly seen in the last of the fading twilight.

"Now," continued the Athensian, "monsieur will be well advised to answer
me truthfully. We do not want intruders in those mountains, whence I
come. We are not ready yet to receive visitors. And monsieur came to pry
into our privacy. Yet it was not for that he has been captured, but for
his thews."

"My what?" Bob stared open-mouthed, scarcely able to believe his ears.

"The strong men among the slaves were not satisfactory this year," said
the other cryptically. "Monsieur is a good fighter. Yes, he will fight
well. He will be well cared-for and be given his chance to distinguish
himself."

Bob stared at the cynical, laughing face of the other.

"What do you mean?" he demanded.

"Monsieur will learn all in good time," replied the Athensian. "Now he
shall eat, and afterwards he shall answer my questions about his
companions." He clapped his hands, and an Athensian guard approached.
The leader indicated Bob was to be led away and fed. "Remember," he
called, "monsieur will answer truthfully, or----" He left the sentence
unfinished. But Bob smelled the threat of torture, just the same.




                               CHAPTER X.
                        SQUELCHED BY AN OSTRICH.


Unlike Bob, Jack after leaving Ali took cautious observations from time
to time to enable him to keep the ostrich herd in sight. He realized the
possibility of being deflected from his course in passing behind the
sand dunes, but by frequent halts when he would compel his camel to
kneel and, retaining the long led rope so as to prevent the animal's
wandering, climb to the top of a sand dune, and lying there, swing his
glasses on the distant birds, he managed to make a wide arc about the
herd without going astray.

When a half hour had elapsed, he rose into sight as agreed and a moment
later saw, through his glasses, Ali making for the ostrich herd. Then he
swung his glasses again over the horizon in the direction where Bob was
supposed to have taken post. But he was unable to see any sign of his
comrade.

A somewhat higher mass of dunes far off the course and more distant
caught his eye, and he entertained the fleeting thought that, perhaps,
Bob in wandering behind the sand dunes had gotten mixed up among the
distant hills. But he had little time for reflection because at that
moment he saw Ali start off in pursuit of the ostrich nearest him who,
seeing his approach, headed away fleetly into the desert.

Jack's first impulse was to dash forward and join in the chase himself,
but he remembered Ali's caution and held his position. Ali's camel was
on a tangent to the flight of the ostrich, and Jack could see his
companion's intention was to head off the big bird and chase it toward
him. In the meantime, the more distant members of the herd, a dozen
great birds, had taken alarm and were galloping away on a course that
lay midway between Ali and Jack, whom apparently they had now sighted.

What a picture it all made, thought Jack. For a while, he sat his camel,
lost in admiration of the sight. The vast waving floor of the desert,
with here and there low clumps of bush; the great birds, black-bodied,
beautiful under the flood of golden, dazzling sunlight, fleeing fleetly
in twenty-five foot bounds; apart from his fellows the one great
ostrich, gradually drawing closer to Jack, with the ungainly camel
humping along in the rear and to one side, continually turning the
ostrich so he could not gain the open desert behind Jack's camel.

In the midst of his absorption, Jack started. Was that a shot? He
listened. But no repetition came. So faint had been the sound that,
perhaps, his ears had deceived him. Certainly, if it were a shot it
could come only from Bob, yet Bob was not in sight. And just as
certainly as Bob would shoot, if he were lost, he would fire a whole
volley. Jack listened with strained attention. Not a sound. He swept the
whole northern horizon, in the direction Bob had taken, with his
glasses.

What was that on the far sand dunes? On those slightly higher hills? A
sudden, quick uptossing movement, and then nothing further. He gazed
fixedly at the spot, but without reward.

A sudden shout from Ali recalled Jack to his surroundings. Great Scott,
what was that! Yes, Ali's camel had stumbled and pitched to its knees,
and Ali had been thrown forward onto the sand. And the ostrich! What in
the world was it doing?

"Lie down, Ali, lie down," screamed Jack, remembering his father's
warning of what a man must do if attacked by an ostrich.

For the great bird which Ali had been pursuing had turned in wild fury
and was dashing headlong for the fallen man, literally skimming the
earth, seeming to touch it only at long intervals. Jack knew the ostrich
cannot use its wings to fly, and employs them only to aid to pivot and
make sharp turnings or to bring its body to a sudden halt. But the great
bounds made by the creature gave it the semblance of flight.

Jack's face went white. Ali's camel had scrambled to its feet and was
heading back across the desert toward the distant oasis. Ali lay still,
outspread on his face. Was he knocked out by the fall, or had he adopted
the customary attitude of hunters when attacked by an ostrich? Jack
could not tell.

One more swoop the ostrich took, and then it folded its great legs
beneath it and sat down on Ali's body. Only the man's feet and lower
legs projected. The big bird's body covered even his head, and Jack knew
he must act quickly or Ali would be smothered.

He was less than a thousand yards distant and well within the range of
his Winchester, but so nervous was Jack, his hands shook so much, that
he decided to approach closer before venturing a shot.

As he moved up, the ostrich began to hiss. A strange hissing note it
was, with the beak not opened and the air from the bird's lungs swelling
its throat and flowing over the vocal organs. Still it continued to
maintain its position on Ali.

Now was the time. Jack knew it was up to him to save Ali's life, and the
thought exerted a steadying influence. He lifted his rifle, took careful
aim, and pressed the trigger. He had aimed not at the body, for he
feared that, unless struck in the heart, the ostrich would not be
killed. Then it would writhe convulsively, and its movements would
increase Ali's danger. Instead, he aimed at the small head.

The next moment, he saw the head droop like the head of a flower broken
from the stem but still hanging by a shred. Then the great bird fell
over on its side, and twitched while its long legs kicked convulsively.

Ali rolled quickly away, turning over and over, instead of first
regaining his feet. By the time Jack arrived, Ali was on his feet and
composedly shaking sand from his burnoose and straightening his turban.
The swarthy face with its gleaming black eyes and black mustache, was
filled with gratitude as Jack approached.

"You saved my life," said Ali. "I'll not forget."

They looked at the body of the great bird, which lay still. Jack
experienced a revulsion of feeling. Why had they ever come out on this
ostrich hunt, anyway? To kill so beautiful a thing seemed a crime. Ali
looked up at him and said:

"We may as well take the plumes now."

"Oh, I don't want them," said Jack. "Let's find Bob."

Ali smiled slightly. He could understand his companion's distaste. As
for him, inured to hardships, was he to be so shaken up by one that he
neglected to pick a small fortune, a tidy sum, in ostrich plumes? Death
of his life, no. He strode to the body of the ostrich and began
methodically to pull out the barbs of the plumes.

In the meantime, Jack through his glasses scanned the horizon, searching
for signs of Bob. Now that the danger to Ali was past, recollection of
the fact that no sign of his comrade had yet appeared, flooded back on
him. What could have become of Bob? Jack was filled with anxiety.
Certainly, no matter whither he had strayed he would have given some
sign ere this. Could his camel have thrown him? Did he lie stunned
somewhere on the desert? That seemed the most likely possibility.

"Hurry, Ali," he called, still sweeping his glance around the desert.
"We must go and look for Bob."

Ali completed his task, having picked the best of the plumes, and left
the rest to fortune, stirred by the peremptoriness of Jack's tone. As he
walked nearer, Jack suddenly voiced a low exclamation.

"What it is?" Ali asked. "Do you see Mister Bob?"

"I thought I saw a man on horseback over there," said Jack, pointing
toward the northeast, where the ridge of higher sand dunes which earlier
had caught his gaze, lying to the north of him, stretched eastward.

"A horseman?" Ali's tone grew alert. "We have no horses here."

"Now I can't see any more," said Jack. "Look here, what'll we do? We've
got to go and look for Bob. He's strayed, that's all there is to it."

Rapidly he outlined to Ali his fears that Bob had strayed from his
course and became enmeshed among the higher sand hills, perhaps had been
pitched from his camel. Ali, whose glasses had been lost in his fall,
scouted around until he recovered them beneath a bush. Then he, too,
examined the sand dunes Jack indicated.

"That horse you saw," Ali said presently. "I don't like it."

"What do you mean?" Jack demanded quickly. "Desert robbers?"

"Perhaps," said Ali. "Although this is off the caravan routes and is not
rich ground for robbers. Perhaps, the Athensians."

"Oh, come now," scoffed Jack. Nevertheless, he, too, experienced a
sudden sense of fear.

"Well," said Ali, "take me up behind you, and we'll investigate. Mister
Bob's trail ought to be easy to follow."

Obediently, Jack caused his camel to kneel and Ali scrambled up behind.
Then, with its double load, Jack turned the beast's head toward the
point where the three earlier had separated. The indentations made in
the sand by the pads of Bob's camel were easy to follow, and in his
anxiety Jack pushed his own animal ahead at a shuffling run. Ali perched
precariously behind him had hard work holding on, but said nothing. He
was as anxious as Jack.

In less than the half hour Bob had taken to reach his station, they
arrived. Then the sorry story lay before them. To Ali's desert-trained
eyes, it was easy to read.

Both Ali and Jack flung themselves from the camel and went scouting
around. Bob's camel tracks, the hoof marks of horses, a broken piece out
of the shield of Bob's sun helmet, and the mass of zinc for a ground for
his radio set, which had become detached from his camel's saddle, all
told what had occurred.

"I'll bet old Bob put up a whale of a fight," said Jack. "But why didn't
we hear any shots?" He explained about the one shot which he had heard.

"Whoever was here," said Ali, gauging the situation correctly, "wanted
to take Mister Bob prisoner, not to kill him."

"But Bob had his Winchester," objected Jack. "Why didn't he use it?
Either they closed in on him too fast, or else it became jammed."

Ali nodded, but did not reply. He was engaged with other thoughts and in
a moment gave Jack the result of his cogitations.

"A half hour for Mister Bob to arrive here, a half hour for us to
arrive," he said. "Not to speak of the time lost in our ostrich hunt.
These men have more than an hour's start of us. They are on horses, and
eight or ten in number. We have a camel, which is slower, and we are
only two. It would be folly to pursue."

"Follow or not," said Jack hotly, "I'll not let old Bob be carried off
without doing my----"

Ali held up a hand and interrupted.

"It will be a long chase," he said. "We must organize for it. Let us
return to the oasis. There are ten of us left. Armed, provisioned,
mounted on our camels who have had a long rest, we can return and pick
up the trail before nightfall. Camels need less rest than horses. Even
though they are slower, by pushing them we may yet cut off these others,
if----"

He gestured toward the distant Shaitun Mountains. Jack nodded
understandingly.

"You mean if they are Athensians and are heading home?" said Jack.
"Well, you are right, Ali. I want to start right away, but your way is
better. Come on, mount, and we'll get back to the oasis as fast as a
camel ever made it."




                              CHAPTER XI.
                         THE STRANGER REVIVES.


Some distance from the oasis, Mr. Hampton and Frank were encountered,
riding to meet them.

"Where's Bob?" called Frank, in an anxious tone. He and the big fellow
were very close. Frank's mother had died when he was a baby, and his
father, business partner of Bob Temple's father, had followed her a few
years later. Ever since, the orphaned Frank had made his home with the
Temples, and he was engaged to Bob's sister, Della.

To Frank's anxious inquiry, Mr. Hampton added:

"When Ali's camel came in alone we knew something had happened and set
out to meet you at once."

"Well, Dad, something has happened all right," said Jack, dejectedly.
"Or rather it's all wrong. Bob has been captured. We don't know how."

Thereupon, while they all made their way back to the oasis, he proceeded
to explain events as they had occurred so far as he knew them. What
actually had happened in Bob's case, of course, was not known. But as
our readers know, Jack and Ali had guessed at the truth.

By the time the account was concluded, they had arrived at the
encampment and dismounted. Mr. Hampton looked very grave and care-worn.
The deaths of the Professor and Ben Hassim already had weighted him
down. Now the capture of Bob, whom he loved as if he were a son, filled
him with grief. A malignant, unseen power seemed pursuing this
expedition, which had started out peacefully intent only on establishing
amicable relations with the mysterious dwellers of the Shaitun Mountains
and on adding to the sum of the world's useful knowledge. Truly, he
thought, gazing out through the trees of the oasis across the vast
reaches of the desert toward the mountains on the far northern horizon,
truly, they were well named the mountains of Satan.

Had he had any premonition of the reception with which they would meet
at the hands of the Athensians, Mr. Hampton never would have financed
nor launched the expedition. But he realized the futility of vain
regrets. Now was not the time to devote to such thoughts. One thing must
be done, one thing alone, and done at once; that was, to start swift
pursuit for the purpose of rescuing Bob.

Turning to the boys, he bade them pack up at once the few things
absolutely necessary, but not to incommode themselves with articles
which could be dispensed with. As they leaped to obey, he ordered Ali to
summon the Arabs. The men who already had received from Ali a brief
account of what had occurred on the ostrich hunt, quickly assembled.
Their swarthy determined faces formed a group at which Mr. Hampton
looked with approval. Picked men all, he could not ask for better
support at his back. Nevertheless, he felt it was only fair that they
should be appraised fully of the dangers attendant upon the proposed
expedition, and should be allowed to exercise their own choice as to
whether to accompany him or not.

"Ali," he said, when all the men were assembled, "I want you to tell
these men that I am going to start at once in pursuit of the band which
has taken Bob prisoner. If we can cut the fugitives off before they
reach the Shaitun Mountains or catch up with greater numbers, as it is
possible another band awaits them, we stand a good chance of rescuing
Bob. But, as I say, it is quite possible this small band of ten men was
merely an offshoot of a larger band. In that case, the others may turn
on us and we could not outrun them and would have to make a fight for
it. Against any such band as that which swept the oasis the night the
Professor was killed, we would stand little chance for our lives.
Therefore, I think it only right that the men should make their own
choice as to whether they go with me or await my return here. If none
go, I'll still make the attempt at rescue with my son and Mr. Frank."

Ali listened impassively, and on the conclusion of Mr. Hampton's little
speech turned to his comrades whom he addressed briefly. Mr. Hampton
watched their faces as Ali was speaking. What he saw pleased him
mightily. A sharp fierce cry, coming as if from one throat, issued from
the group at the conclusion of Ali's words. He turned to Mr. Hampton
with a satisfied smile.

"They all go," he said simply.

"Good," said Mr. Hampton, not a little affected. "Good."

"They say Mr. Bob is worth dying for," added Ali. "Every man loves him.
If there is a fight and they die, well, you know, sir, Paradise awaits
the Arab who falls in battle."

Mr. Hampton nodded, unable to trust himself to speak for a moment, as he
thought of Bob and the devotion of these Arabs to him. Then when he
found his voice he added huskily:

"If any man dies, I'll provide for his family, Ali, if he has a family.
And to all I'll give double wages for the entire trip should we get
safely back to civilization. Tell them that, please. Also, I'll give
each man right now, or as soon as I can write it, an order on the Cairo
bankers for 25 pounds (about $1,250). Thus, if I fall, the men still
will be provided for."

Ali repeated Mr. Hampton's words, and a hum of approval rose from the
half dozen Arabs. The sum mentioned was more than any one of them ever
dreamed of possessing at one time, and would represent affluence,
indeed.

While the Arabs, under Ali's direction, sorted out the equipment to be
taken and baled up the remainder to be left at the oasis in charge of
old Allola, Mr. Hampton retired to his tent to write the necessary bank
drafts. Also, he drew up a document for his Cairo bankers, incorporating
the provisions of his pledge to the Arabs, which he intended to leave
with Allola, with explicit instructions that it should be sent out of
the desert by the first trustworthy rider who should appear at the
oasis.

To Allola, he made a handsome present in money. As for the old woman's
welfare, she had the sheep and goats, the garden patches, the fig trees,
and would not suffer for sustenance, should they fail to return. Soon or
later some Bedouins of the desert would arrive at the oasis, moreover.
And, as, despite her age, the old woman was spry and could get about
easily, she had little to fear.

Disposition of the wounded Athensian puzzled Mr. Hampton. All day the
man had been tossing and muttering at a great rate, and Mr. Hampton
believed that the fever was leaving him and that in another day or two
he would recover consciousness and could be questioned. Even as he
wrote, he was conscious of the other man muttering on the divan behind
him.

Going to the door, Mr. Hampton called Allola to him and into her care
gave the papers he had drawn with explicit order for their disposal,
together with a sum of money not only for herself but for the messenger
she should select. Of the old woman's honesty and willingness to carry
out his orders, he had no doubt whatsoever, as gratitude for her rescue
made her slave-like in devotion.

He noted the Arabs loading the camels lightly, and storing the balance
of their equipment in one of the tents. With approval he saw Frank and
Jack putting the Professor's radio sending apparatus, in its shallow
trunk, on one of the camels. There was always the possibility that it
would come in useful, and Frank had finished restoring it to order only
that morning.

Then while he still talked to Allola Mr. Hampton heard a sharp cry from
the tent, and whirled around. It had come from the wounded Athensian.
With Allola at his heels, Mr. Hampton hurried to the other man's side
and bent down to look at him. He gave an exclamation of surprise. The
man's eyes regarded him in puzzled bewilderment, filled with the light
of returning reason. Putting a hand on his forehead, Mr. Hampton noted
it was cool and moist, indicating the last of the fever had fled.

The other continued to stare at him, unbelievingly, and Mr. Hampton
decided to see if his prisoner really had been restored to his senses.

"Do you know where you are?" he asked, slowly, in the Athensian words
taught him by Professor Souchard.

Almost it seemed as if fear leaped into the man's eyes. Certainly they
were filled with amazement.

"Who are you?" he demanded.

"I am a stranger who was passing by and saved you when otherwise you
would have died," said Mr. Hampton.

"You do not speak my tongue well," replied the other slowly. "How is it
you speak it at all?"

"That explanation can wait," said Mr. Hampton. "In the meantime, I have
a question or two to ask, which I hope you will be good enough to
answer. Excuse me, first."

With a whispered injunction to Allola to stay or watch, he hurried out
of the tent and called Jack, Frank and Ali to him. Briefly, he explained
the prisoner was conscious, and that they must delay a few minutes in
order that he might be questioned. It was possible that from him some
information of great value might be obtained.

Returning, Mr. Hampton found Allola giving the Athensian a drink from
the canvas water jar which always was kept hanging in the draught at the
doorway so that evaporation kept the water cool. He was turning over in
his mind the possibilities, and wondering which of the many questions
crowding for answer he should put. His small stock of Athensian words,
moreover, complicated the task. But the other, palpably refreshed and
strengthened by his drink, solved a portion of his problem by addressing
him in French as he approached.

"Monsieur, doubtless speaks French," said the Athensian cooly. "This
knowledge of my language is deplorable. Let us speak therefore in
French."

"Agreed," said Mr. Hampton. "Only, let me say that your surprise at my
partial knowledge of your language was no greater than mine at hearing
such excellent French from your lips."

"How long have I lain here?" asked the man abruptly.

"Ten days," said Mr. Hampton.

"And you have cared for me all that time? I must have been very ill."

"I have cared for you," said Mr. Hampton gravely. "And you were ill,
very ill, you came close to death."

"Ah," muttered the Athensian, his eyelids fluttering shut. They remained
so a moment, then snapped open with the effect of a camera shutter's
quick flicker. Mr. Hampton was surprised at the vigor of the other's
glance. "And has no attempt been made by others to come and get me?"

"None," said Mr. Hampton.

"Ah," said the man once more. Again his eyes closed. Again they opened,
and this time they seemed filled with ferocity.

"Would monsieur say I had been left as if it were believed I was dead?"
he demanded.




                              CHAPTER XII.
                             AMRATH SPEAKS.


What all this was leading to Mr. Hampton could not surmise, but he was
content to bide his time a moment longer, pretty well convinced by now
that the other was leading up to some denouncement.

"Yes," he stated judicially, "I would say that whoever saw you would
have considered you dead. I myself believed so when we discovered you.
It was only after various tests that we were convinced you still lived,
and since then I have had a struggle to bring you back to sanity and
consciousness."

"I suspected it," said the man, grimly. "Let me think a moment
monsieur." Again he closed his eyes. For not only one but several
minutes he continued to lie with his eyes closed, but that he not only
was awake but thinking tumultuous thoughts was apparent to Mr. Hampton
from the flush that mantled the man's cheeks and from the labored rise
and fall of his chest.

"Monsieur," said the man, snapping his eyes open again, "you have been
good to me. I can see that. I am not ungrateful. My people attempted to
kill me. They left me for dead. I am convinced of it. Now I shall
foreswear them. I shall be your friend, as I was the friend of Professor
Souchard."

It was Mr. Hampton's turn to exhibit surprise.

"Professor Souchard's friend?" he queried in amazement.

"Another drink I beg you, monsieur," pleaded the Athensian. Mr. Hampton
obediently poured water from the jar into the cup, and set the latter to
his lips. "Ah," said the Athensian, satisfiedly, "that is delicious.
Already I feel myself growing much stronger."

"And now," said Mr. Hampton, "my time presses. Some of your people have
captured my son," he added, to avoid needless explanation of Bob's
identity. "And I was about to set out in pursuit and attempt his rescue
when you became conscious."

"Tsst, tsst," clucked the other, sympathetically. "That is bad."

"A big fine fellow, six feet tall, an athlete," said Mr. Hampton,
thinking of Bob's fine appearance. "Well, I imagine he mussed up a
number before they took him."

"An athlete?" queried the other, alertly. "And they did not shoot but
took him prisoner. Monsieur, that is very bad, very bad, indeed."

"Why, what do you mean?"

"I have been here ten days," said the other thoughtfully, seeming to
disregard Mr. Hampton's question. "Yes, the Sacrificial Games, them, are
five weeks, no, six weeks, distant."

Again Mr. Hampton demanded, this time a sharper note of anxiety in his
voice, what the Athensian sought to convey.

"Just this, monsieur," said the other; "that your son is destined to
take part in the annual Sacrificial Games of my people. Every year
twelve of the strongest men from the outside world who can be found,
either taken prisoner by us in battle or raid, or bought in the slave
mart of Gao, are pitted in single combat against an equal number of
Athensian youth. The victor in each contest is then pitted against
another victor. Thus the competition is narrowed until only two remain.
These combats are to the death. The winner is worshipped one whole year
as the embodiment of the God of Strength. At the time of the annual
Sacrificial Games of the succeeding year he is killed as a sacrifice."

"Good heaven," said Mr. Hampton. "And is that the reason for this
purchase by your people of the strongest slaves in Gao, of which I have
heard?"

"Monsieur has heard?" queried the other, surprisedly. "Yes, that is the
reason."

"I can't stay any longer to talk to you," said Mr. Hampton,
emphatically, springing to his feet. "I must set out at once to rescue
Bob."

"But a moment, monsieur," pleaded the other. "I would like to go with
you, but I am not strong enough. See, I cannot more than lift my arm,"
he added, suiting action to word.

"Yes, yes, I know," Mr. Hampton said, impatiently. "But I must be off.
Allola, this old Arab woman, will look after you until my return. And if
I fail, well----" A shrug of the shoulders completed his sentence.

"Monsieur must not fail if he would see his son again," the Athensian
said. "But before you go, let me explain. I shall be brief."

Mr. Hampton unwillingly returned and the Athensian continued:

"I met Professor Souchard on one of his scouting expeditions about the
base of our mountain wall. I am an exile from Athensi, monsieur. How I
come to speak French is easily explained. I am of the priest clan, and
our young men for ages have been sent into the outside world for a
certain period of study. Always this has been so. We made our way into
Egypt under the Pharaohs. When Carthage rose, we were represented there.
At the height of Rome's power, our young men were at her court, learning
the secrets of her civilization and power. Through each succeeding age,
we have gone out across the desert and entered the halls of learning of
the dominant races of civilization. I was one of those selected to study
the French, and I have served in the French Foreign Legion in Algiers.

"Then we return after a certain time, not to give the benefit of our
acquired knowledge to our people, who are steeped in ignorance, being
little better than the Kabyles of Northern Africa, who, as monsieur
doubtless knows, are a semi-savage white race living in the mountain.
No, we exercise this knowledge to retain our power. Some day there will
come a revolution. I was one of those not contented with this abuse of
power. I felt our country should be developed, and opened to
civilization, surrounded though it is on every side by the desert. For
this, I was an exile to Korakum.

"Another drink. I beg, monsieur. Ah, that is better. I draw near the
finish of my words. Monsieur, I see, is anxious to be gone. Well spies
of the Oligarch saw me converse with Professor Souchard whose first
escape from Korakum had been regretted by the priest clan as a mistake.
And heavily did they punish those who aided him then. Heavily monsieur.
They paid with their lives. For the priest clan does not wish
civilization from the outside world to enter our mountains, lest the
power of its members be shattered.

"But I have friends. Knowledge that I had been spied upon in my
conversations with Professor Souchard was not unknown to me. It was only
recently I had met him, on the next to last trip he made into our
region. When he came the last time, I met him out on the desert and
warned him the expedition which he and you, monsieur--for I suppose you
are the comrade he awaited--must turn back. He had not known before of
the priest clan, nor of all this I have told you so sketchily. He said
he would meet you at this oasis, and that he would tell you what I told
him and go back with you across the desert.

"On returning to the mountains, monsieur, I hid beside the outbound
trail. Hours later, a friend came to me with word that the Athensian
spies were starting with an expedition for the oasis, determined to kill
Professor Souchard and his man, Ben Hassim, rather than let them escape
and bring the world about our ears.

"I had a horse. I mounted, and with a bag of food and several water
bottles, set out to overtake my friend. Five days I rode, not sparing my
horse. Then he dropped dead, and I staggered on the last half day afoot.
But the Athensians overtook me.

"I was not killed monsieur. I was carried along to the oasis with them.
At its edge, the world went black to me." He paused. "That is all,
monsieur. What has happened since, you know better than I."

Mr. Hampton drew a long breath. The spell of the man's tersely told
story had held him enthralled.

"They garroted Professor Souchard and Ben Hassim," he said.

The Athensian's lips compressed. "A trick of the priest clan's followers
for disposing of enemies," he said.

"And you were hit a blow on the back of the head, and left for dead
beside them. It was there we found you."

"Ah," said the other, composedly. "They lied to me. They said my life
would be spared." A long pause followed, during which he raised a
languid hand to brush his eyes. "My name, monsieur," he added, "is
Amrath. I have delayed you, but not for long. Go now, and luck be with
you. In the Valley of Korakum, should you reach it, you will find true
men named Jepthah, Amonasis and Shilluk. Should it be your fortune to
meet them, call upon them for help in my name. And now, luck be with
you. I shall await your return."




                             CHAPTER XIII.
                            KORAKUM REACHED.


The Athensian's lengthy conversation palpably had tired him, and Mr.
Hampton summoned Allola who had gone to the door of the tent to watch
the final stages of the Arabs' preparations for departure, and ordered
her to prepare broth at once for Amrath. He also left with the latter
one of his precious bottles of brandy, advising him to sip it sparingly.

Good-byes were said, and he was on the point of departure. In fact,
already he had left the tent when Allola came running after him,
summoning him in dumb show to return.

"A bit of advice, monsieur," said Amrath. "Your one opportunity to
intercept the party bearing away your son lies not in following their
trail. It will be circuitous in order to pass by three small water holes
in the desert of which we Athensians know. That is necessary because of
the horses. But you, with your camels, need not strike those water
holes. Take a supply of water in your water bottles, and strike due
south. The only way to enter the mountain wall is through the old stone
road leading into Korakum. There is another trail, which was destroyed
ages ago, and which we revolutionaries secretly have been rebuilding.
The spies set upon us recently may have reported that to the Athensian
authorities. But, doubtless, this party will take the easier route.
Therefore, I would advise you to seek the old road, which lies due south
of this oasis and enters the mountains by the only accessible pass.

"If you arrive in time, seek out Jepthah, Amonasis and Shilluk in
Korakum and with their aid make an ambush. That is all," he concluded,
faintly, his exertions beginning to show on him. He clasped Mr.
Hampton's outstretched hand and pressed it to his forehead. "Believe me,
monsieur," he said, "I am not ungrateful. Amrath wishes you well. And,
who knows? Together we may yet bring happiness to my backward country."

Making a mental note of the directions given and especially of the names
of the three friendly exiles of Korakum now twice repeated, Mr. Hampton
bade Amrath farewell. Drawing Allola with him, he ordered Ali to lay
upon her the strictest injunctions for looking after the Athensian's
welfare, stating the man was a friend. Further, he advised her that
should he fail to return she was to give Amrath on his recovery the
documents left in her possession and destined for the Cairo bankers,
feeling assured the Athensian would deliver them.

Everything now being ready and Frank and Jack especially being wild to
start, the party set out. Amrath's advice was repeated to Ali, who
nodded agreement.

"That is good sense," he declared. "If we followed the trail, as your
man says, we might and probably would be too late. They would escape on
their fleeter horses. But by shortening the distance to the mountains,
we may arrive ahead of the raiders."

Day after day the party now pushed on south into the desert, resting two
hours in the hottest part of the day but making up for the delay by
riding far into the cooler night. The camels were pushed almost to the
limit of endurance.

Daily the Shaitun Mountains loomed larger on the southern horizon. A
sharp lookout was kept for sight of other travellers, but none was seen.
Except for the gray shape of an occasional jackal scuttling off through
the bush into his sand burrow, or a herd of ostrich seen at a distance,
nothing alive appeared in that vast waste of sand dunes and stunted
bush. No trees broke the horizon, once the oasis of Aiz-Or had been left
behind.

This failure to sight the raiders carrying Bob into captivity was
variously interpreted by members of the party. Mr. Hampton and Ali,
older and less optimistic than the boys, were inclined to believe it
meant that the raiders had too great a lead, due to their several hours'
start and their swifter mounts, and had completely outdistanced them.
Jack and Frank, on the contrary, scorned this interpretation. To them
the absence of any sight of the raiders meant that the route the others
followed was so circuitous as to be completely below the horizon and
that, accordingly, the chance of reaching the mountains in advance of
the raiders was good.

"And, believe me," said Frank, during the course of one discussion,
"when we spring our ambush, if they show any signs of resistance, I'll
have no compunctions about shooting."

"Same here," said Jack. "For once in my life I'll shoot at human beings
without a qualm. The bloody scoundrels. Carrying off old Bob to make a
Roman holiday for 'em. Either he'd be killed in one of their single
combats, or, if he won, he'd be fattened up for a year and then
sacrificed to their idols. Brr."

Mr. Hampton nodded.

"I agree with you boys," he said, quietly. "If we get the opportunity,
we must not throw it away through faint-heartedness or misplaced
kindness. These Sacrificial Games of which Amrath spoke constitute a
bloody rite which is out of tune with modern times. The idea of Bob
being compelled to fight for his life, without any real chance of
winning, even if he conquers all others, makes me shudder."

Jack and Frank were silent a long time, filled with oppressive thoughts.
Yet in the end, a grim smile spread over Frank's face and he appealed to
his comrade with:

"Just the same, Jack, it would be a great sight to see old Bob doing the
gladiator. He's an expert fencer, wrestler and boxer. Let them arm him
as they will, he'll put up a real battle. I wouldn't be surprised if he
beat all contenders."

"You bloody-minded barbarian," said Jack. "I believe you'd like to see
such a contest."

"Well," said Frank, "if it can't be avoided, I want a ringside seat,
that's all."

Mr. Hampton's lips twitched, although he shook his head in deprecation.
Youth must be served, he knew well. The delight of the three young men
in sports always had seemed to him wholesome and worth while. From their
earliest knee-pants days he had encouraged them in all sorts of athletic
exercises. They swam like water dogs, ran like Mercuries, fenced like
D'Artagnan, and as non-professional boxers and wrestlers stood high. But
of them all, Bob was the most expert boxer and wrestler, due in a
measure to his greater physical strength, while, as Frank had said, he
was no mean hand with the foils. Should he be pitted with sword and
shield against almost any warrior, he would give a good account of
himself.

Frequently, these rest-period discussions turned on the question of what
should be done if they failed to intercept the raiders and effect Bob's
rescue, as well as on what plan to follow if the small raiding party
joined hands with a larger Athensian force.

Mr. Hampton was of the opinion that the latter contingency was quite
likely to arise. Apparently, secure in their sense of isolation, the
Athensians had not maintained outer guards of their mountain land at the
time Professor Souchard first arrived at Korakum. Otherwise, it would
not have been possible for him to escape. But that now such a guard was
maintained seemed to Mr. Hampton more than likely.

Against this assumption, however, Jack argued with great good sense that
Amrath would have been aware of such a guard, and would not have advised
them to attempt to enter Korakum and seek out his comrades had a guard
existed.

The only plan they could reach for use in case of attack by superior
number was to compel the camels to kneel in a circle and from the
interior of such a fort of living flesh put up the best fight possible.
With their repeating rifles and plenty of ammunition, it was possible
they could inflict such damage as to compel the withdrawal of the enemy.
If not, well----

"If old Bob has got to go, I'd just as soon go with him," said Frank.

Jack nodded solemnly.

As for the Arabs, said Ali:

"When we die in battle, we are sure of Paradise. The Prophet so
promised."

In case they failed to intercept the raiders and rescue Bob, Mr. Hampton
planned to hunt out first the Korakum exiles whose names had been given
him by Amrath, and whom he took to be leaders of the revolutionaries. It
was possibly that they could be induced to aid in some plan for stealing
Bob from Athensi before the holding of the Sacrificial Games, which
Amrath had said were six weeks away. Failing to gain such aid, Mr.
Hampton believed it possible the exiles might at least supply
information which would enable them alone to penetrate the enemy's
stronghold and try to rescue Bob. For to this course, Jack and Frank had
declared openly they would commit themselves, come what would.

And Mr. Hampton knew it was useless to try to dissuade them. Both were
of age and, although guided by him ordinarily, in this matter they would
act as they saw fit. Either they would rescue Bob or die in the attempt.
The bond of union between the three inseparables was so sure and firm
that Mr. Hampton would not attempt to go against it, even though it
might mean the loss of his own son. As a matter of fact, he himself was
equally determined to go the limit in attempting to rescue Bob.

As matters fell out, they were enabled to make the last march bringing
them to the Shaitun Mountains entirely under cover of darkness. By
saving their camels the latter half of the day, they covered the
remaining distance at night, and arrived at the pass--plainly discerned
through Mr. Hampton's night glasses--in the early morning hours, before
the sun was up.

Should they enter and hunt cover, or reconnoitre the mountain wall to
either side first? This question had been left until the last moment for
decision, as naturally the lay of the land would influence them.

On arrival, so gradually did the great stone road rise out of the sand
and pierce the mountain pass, with bare steep walls on either side,
devoid of verdure, that Mr. Hampton believed it was safe enough to push
ahead. On those great rocky slopes, where the levelling process of
Nature had been assisted by man in that dim age when the road first was
built, by no possibility could men lie hidden. At this point they could
neither ambush nor be ambushed.

Before proceeding, however, the sand was inspected by Arabs afoot for
any signs that would indicate the recent entrance of horsemen into the
pass. None was found. Then the marks left by the scouts were carefully
obliterated.

For a considerable distance, as they approached the pass, the camels
were made to walk in single file, and two Arabs, walking backward at the
rear of the procession, smoothed out all signs of their passage. In
broad sunlight, anyone hunting for a trail, would find it. But to a
cursory glance it would remain invisible.

Satisfied that everything possible had been done to prevent the raiders
whom he now felt assured had not yet entered the pass, from discovering
he was ahead of them, Mr. Hampton ordered the party to proceed
cautiously along the great stone road.




                              CHAPTER XIV.
                          A NEW RADIO STATION.


The moon had been down for two hours or more. They had so timed their
approach as to make the last part of their journey come at the darkest
time of night, in order to minimize the risk of being seen by any spies
on the mountain.

In the distance, on either hand, stretched away to the horizon a great
mountain mass, the outer walls of which Mr. Hampton estimated to be
2,000 feet at least in height. Steep precipitous slopes of rock, as far
as they could judge, made ascent next to impossible. Here, in this pass,
however, the mountain walls were slightly lower. Yet, as they proceeded
slowly up the stone road, which ascended gradually but steadily, going
carefully, with an Arab well in the lead as they approached each turn in
order to give warning against surprise, the walls were steep enough in
all seeming.

Conversation had been forbidden, and only the soft padding of the camels
broke the silence. Yet each man thought to himself that it would be
impossible to scale those slopes, and prepared to fight to the death
where he stood in case of attack.

It was even darker in the pass than it had been on the desert, where the
soft diffusive light of the stars gave a faint illumination. They rode
two abreast, and Jack and Frank, who rode together, could make little
out of their surroundings. They were in the middle of the line and could
barely see the men ahead and behind them--dark, hooded shapes all. For
Mr. Hampton and the boys wore Arab burnooses and, except for their sun
helmets, which they wore in place of the Arab turban, resembled their
companions in appearance.

Of the road itself little could be seen, except that it was smooth and
without breaks, composed of immense rocks which could have been moved
from a quarry and put in place only at the expense of Herculean labor,
especially in that dim bygone age when laid down. Filling the pass from
wall to wall, it was a road built for the ages. How deep it went, who
knew? Certainly, it must have been yards in depth. Over the surface, one
would have expected sand from the desert to have collected, but so free
was the stone from any such accumulation that it seemed to be
newly-swept. Winds playing up and down the pass like the draught in a
chimney were responsible.

Suddenly the Arab riding far in the lead to guard against surprise, as
similarly rode a single Arab well in the rear of the main body, fell
back beside Mr. Hampton and Ali who headed the procession.

"What is it?" asked Ali, low-voiced. "Men ahead?"

The other whispered softly to him, and Ali turned to his anxious
companion, and interpreted in a relieved tone.

"Akmet says there is a little pocket ahead in the canyon wall," he
whispered. "He cannot see well because of the darkness. There are trees
and bushes. He will not go in alone. Akmet," said Ali, in a tone of
scorn, "does not fear to find men, but he is afraid of spirits. He wants
the Master to accompany him because he is a great wizard."

In the darkness, unseen by Ali, Mr. Hampton smiled. This child-like fear
of _djinn_ or spirits he had noted among the men on other occasions.
Early in their association, whiling away hours in camp as they crossed
the Great Desert toward the oasis, he had performed some intricate
tricks of magic which had made a great impression on the men. That they
believed him a wizard, he knew.

"Very well," he said, "tell Akmet to lead, and I'll follow. Do the rest
of you remain here until we return."

Then the forms of the two men melted into the darkness. A considerable
time elapsed before their return and Jack, alarmed despite the absence
of shots or other sounds which would indicate his father had encountered
trouble, was arguing with Ali who barred the way to be permitted to go
in search, when his father and Akmet returned.

"Just the place for us," said Mr. Hampton, in a tone of satisfaction,
still speaking in a low voice. "A little grassy plateau, slightly above
the level of the road and stretching back under a steep overhanging
bulge in the rocky wall of the mountains as far as we could judge. Some
wild fig trees have grown up there and the grass is luxuriant. There is
a spring of water at the rear. The plateau is about an acre and a half
or two acres in extent, running back under the rock rather than
alongside the road. The trees will screen us, there is water, grass for
the camels, and we will be protected from attack overhead. We could make
a stand there against an army, if necessary."

Expressions of satisfaction greeted this announcement, and with Akmet
and Mr. Hampton in the lead, the whole party, which the rear guard had
joined during its halt, proceeded to the retreat.

Things were as Mr. Hampton had described and, after bedding down the
camels at the rear, and rearranging the screen of bushes where they had
entered in order to hide signs of their passage, all lay down to snatch
a few hours' sleep except the two guards. Jack and Frank begged so hard
to be given the task of keeping guard that Mr. Hampton, knowing their
anxiety regarding Bob, gave his consent.

Two hours later came daylight without an alarm having been sounded. Then
the two boys reluctantly summoned Ali and another Arab, as had been
arranged, and rolling up in their burnooses flung themselves on the
grass. They were firmly convinced that sleep would be impossible but
nature had her way with their overwrought systems, and they sank fathoms
deep in slumber. It was well past noon before Mr. Hampton aroused them,
and their looks of astonishment at discovering they had yielded to sleep
were so comical that he chuckled with silent laughter.

Before they could speak he laid a finger on his lips, enjoining silence,
and then in a low voice added:

"We haven't seen anybody nor heard a sound. But it is well to be
careful. So keep your voices down."

While they breakfasted, Mr. Hampton sat beside the boys, and a sudden
thought came to Jack which caused him to jump up excitedly.

"Look here, Dad," he said. "We've got the Professor's radio apparatus
with us. Frank put it in good shape. Now, it just occurred to me that
when Bob left the oasis with me to go on that disastrous ostrich hunt he
had a receiving set--our little pet set--tucked away with him. The
instruments were in his helmet. The phones and the wire for antenna and
ground, were on his saddle.

"It sounds crazy, I know, but it's just possible that he may have
managed to persuade his captors to let him fiddle with the contraption.
They wouldn't know what it was for, and they might let him amuse himself
with it. Why not set up the sending apparatus, and try to send him a
message. It's just a chance, I know. But still, if we should manage to
let the old boy know we were waiting to rescue him, it would cheer him
up, and it would put him on his guard, too, so that he could look out
for himself when the attack comes."

Mr. Hampton, thus appealed to, was tempted to smile tolerantly. It
seemed to him, indeed, crazy to believe Bob would be able to receive a
message. Yet he was too kind-hearted to hurt the feelings of his son and
of Frank, who also hung on his decision. Their anxiety about Bob was
known to him. In fact, he shared it. To be doing something, anything,
would help relieve the tension on their nerves.

"All right, Jack," he said, "go ahead and try it. Can't do any harm, and
if you do manage to reach Bob, even though he can't let you know you
succeeded, you certainly will be of comfort to him."

When he thought of Bob's predicament, of the mental torture the poor
fellow must be undergoing, Mr. Hampton was filled with despair. He
turned away to keep the boys from reading his thoughts in his face.

Jack, however, was very close to his father in spirit. Many a time, he
showed an uncanny ability at reading his thoughts. As Mr. Hampton strode
abruptly away, he turned to Frank and whispered:

"Dad's in the dumps. He doesn't really believe we can rescue Bob. I can
tell, all right. But, somehow, I have a different feeling myself."

Frank nodded soberly.

"I can see how your father feels, too," he said. "I don't quite share
your optimism. Things look pretty black to me. After all, you must
remember, that fellow Amrath told your father there was another way
beside this to pass through the mountains to Athensi. Bob's captors may
have learned about the exiles having repaired it, and may take it."

"I wonder," said Jack, thoughtfully, "what measures Father has taken to
keep watch for the approach of Bob and his captors. Think I'll ask him,"
he added, rising.

"Go ahead," said Frank, draining the last of his coffee. "I'll be
getting to work on the radio in the meantime."

Presently Jack returned with word that one of the Arabs had been out to
the mouth of the pass where, posted with glasses, he could maintain a
sharp lookout over the desert, while another had been sent scouting up
the Great Road toward Korakum.

"I had a look at that road, Frank," added Jack. "Believe me, it is a
wonder. It is composed of great slabs of quarried rock two or three
yards square. The road is all eighty feet wide, Dad estimates. And the
ruts! Man alive, you ought to see them, not deep, but innumerable, from
the passing of chariots in the ancient days Dad believes. He says that
at one time, undoubtedly, the road led out into the desert, perhaps
clear to Egypt. But of course the shifting sand has covered it deep by
now."

"Hand me that coil of No. 14 wire, will you?" asked Frank, absorbed in
the business of connecting up his motor with the double-pole switch.
"There," as he leaned back, to contemplate his work with satisfaction,
before resuming.

"Have you thought, Jack," he asked, "of how fascinating it is to camp
beside this Great Road? Think of the history it has made. History so
ancient there is no record of it left."

"Oh, yes, there is a record," corrected Jack. "Wait till we start
deciphering the papyrus rolls in the library of Athensi."

"I'm afraid we'll wait a long time for that," commented Frank,
completing the connection between one pole of the switch with a post of
the primary coil of the alternating power transformer. "A long time."

"Pessimist," said Jack, stooping down and connecting the other post of
the primary coil with one of the posts of the key, then connecting the
other pole of the key with the second pole of the switch. "Pessimist,"
he repeated, "you've got a bad day, that's all."

"I have," said Frank, with conviction. "Wish I could feel as optimistic
as you. But it strikes me poor Bob is in one fix, and we stand a poor
chance of rescuing him."




                              CHAPTER XV.
                      MEETING THE REVOLUTIONISTS.


While the boys continued their operations, they talked continually in
lowered tones over the possibilities of the situation. No matter what
turn the adventure should take, they were firmly determined not to leave
the desert alive without Bob. Each felt in his heart that he would never
dare face life if he deserted their comrade in his hour of peril.
Despite his more buoyant spirits, Jack realized the difficulties of
effecting a rescue should Bob ever get inside Athensi as well as did
Frank.

Presently they became silent, to some extent by reason of absorption in
their work, but also because their thoughts had strayed elsewhere. Frank
in spirit was back at their peaceful home on the far end of Long Island.
He could see the great house of the Temples, homey and comfortable,
among the spreading elms and maples. He could see the tennis court where
so often he had performed, and flying over it was a familiar figure in
short white skirt, hair bound back with a bandeau, vigorously wielding
the racquet against an unseen opponent. Della.

It would be tough to pass out without seeing her again. But tougher
still to have to go home and acknowledge that he had let her brother be
captured and carried away to certain death without having done his
utmost, even to life itself, to rescue him.

"If I don't come back, old scout," he muttered, soundlessly, "maybe word
of it will get to you some way."

"Here," said Jack, "quit talking to yourself."

Frank looked up guiltily. "Did--did--you hear what I said?" he asked.

"No," said Jack. Then he regarded him fixedly. "Della's the real stuff,
Frank," he said. "She's worth everything."

Frank dropped his eyes, but reached out to squeeze Jack's hand.

Mr. Hampton slid into position beside them. His approach had been
soundless. He appeared worried, and laid a finger on his lips to enjoin
silence and, as Jack half rose, pulled him down beside him. Then
motioning Frank to draw near, he whispered the startling information
that a troop of horsemen was approaching along the Great Road from the
direction of Korakum.

"The scout sent up the Great Road brought back the information several
minutes ago," he whispered, "and as he said the horsemen still were some
distance off, I sent him down the pass to bring in the man stationed
there, who, otherwise, would have been cut off. Both have just returned.
I suppose you fellows were too busy to notice what was going on. Get
your rifles and come along."

Without further words, he turned and walking bent over made his way back
toward the front of the plateau where Ali and his Arabs awaited. The
boys, with beating hearts, seized their rifles and followed.

What did this portend? Was the band of horsemen coming to attack them?
Had they been discovered? Or were the Athensians riding out to meet and
escort back the raiders? Either contingency spelled disaster to their
project for Bob's rescue. Frank and Jack felt their hearts sink.

The front of the plateau, at the edge of a terrace sloping ten feet down
to the road, was narrow. Their force of ten was sufficient to defend it,
as Mr. Hampton had said, against an army. Lying down, a yard or two
apart, they were able to cover it completely. Moreover, the thick
underbrush afforded an effective screen against detection. Unless it
were known they were there, or unless their presence was betrayed by
some noise made by the camels, they could lie securely hidden.

Little time for speculation was afforded. Barely had the boys crept into
the holes left for them in the center of the line, between Mr. Hampton
and Ali, when the ringing sound of horses' hoofs, echoing between high
walls, announced the near approach of a considerable body of horsemen.

Then around the next bend above them came the leaders of the troop,
riding four abreast, with loose rein, and followed by rank on rank,
until a full hundred men appeared. In the lead rode the captain on a
splendid black horse, not large, but beautifully built, a perfect
thoroughbred. This captain was a young man, still in his thirties,
beardless, bronzed, with the same hawklike nose of Amrath. The men in
rank were some young, some middle-aged, and their appearance was
startling. No two were dressed alike, although some form of the
knee-length toga was worn by all. Some wore leggings, others rode
bare-legged. Some wore remarkable helmets, not on their heads, but
dangling at saddle bow, helmets of curious and exquisite workmanship.
Some wore shirts of mail, of very fine links. One or two wore steel
corslets. For arms, all carried long bows, quivers of arrows slung
across their backs, short heavy swords by their sides like those carried
by the ancient Roman centurions, and heavy spears. Perhaps a third also
carried rifles.

Rank on rank this troop rode past the plateau without conversation in
the ranks, each man sitting easily in the saddle, grim faced or
thoughtful. On every face was a look of fine intelligence, and quite
evidently the force was composed of superior men.

Jack and Frank were in a daze, lying with eyes glued to the strange
sight, unable to puzzle out the meaning. Was this a troop of Athensian
cavalry? Then why the ragged dress of the riders? As for Mr. Hampton,
he, too, wondered, recalling that Amrath had said the common people of
Athensi were steeped in ignorance. So, too, would be the Janissaries of
the priest clan. Yet these men, stern and grim-faced all, looking like
fighters, yet also had an appearance of great intelligence which he
could not reconcile with his preconceived opinion of what the soldiers
would be like.

Bathed in the sunlight which fell into the canyon from almost directly
overhead, so that the windless air was close and languid, the troop
passed quickly, and the last rank came in sight. Only three men rode in
it, and as they came abreast of Mr. Hampton one of this number, a fine
looking young fellow of medium height, with crisp curling hair lying
damp on his bared forehead, turned in the saddle and called to the
fourth man some distance in the rear:

"Jepthah, close up."

Mr. Hampton's heart seemed to turn over in his breast. As for Jack and
Frank and Ali, to whom he had repeated his conversation with Amrath,
they, too, recognized the name of one of the exiles of Korakum described
as "true men."

"Coming, Amonasis, coming," called a voice merrily, and the man
addressed as Jepthah came in sight. "A stone in his hoof," he said
patting the neck of his horse.

Again the repetition of a proper name caught the ears of his listeners.
Amonasis. Another of those true men of Amrath's tale. Only to Mr.
Hampton, with his partial knowledge of Athensian, was the import of the
conversation between Jepthah and Amonasis understandable, however.

"Let us halt a moment and await him," said Amonasis to his two comrades,
and they nodded.

All drew their horses toward the grassy terrace of the plateau, and the
animals, dropping their heads, begun to nibble the grass. Not six feet
from the screen of bushes behind which lay Mr. Hampton, to whom they
were nearest, were they. An illuminating idea which had been struggling
for birth in his mind from the first sight of the horsemen burst into
full being. These were not Athensian Janissaries. On the contrary, they
were revolutionaries exiled to Korakum. Simultaneously with the thought
came the decision to speak to them, and Mr. Hampton called cautiously in
the Athensian tongue:

"Don't move, Amonasis. Our rifles cover you. See."

He poked the barrel of his rifle through the screen of bushes almost
into the face of the stupefied man who he addressed.

"Call Jepthah," Mr. Hampton continued. "I have word for you two and for
a third man, Shilluk, from your friend Amrath."

"I am Shilluk," spoke up another of the three, while Amonasis beckoned
Jepthah to approach and rapidly repeated what Mr. Hampton had said,
"Besides," added Shilluk, "this is my brother, Shedrach"--pointing to
the fourth. "We be all true men. What sayeth Amrath?"

"Come forth that we may see you," said Amonasis. "Be not afraid."

"What of the others who have gone before?" asked Mr. Hampton, with
difficulty mastering all this Athensian.

"They be true men, too," said Jepthah, in a tone of satisfaction.
"Amrath should have been with us these last two days. There was a great
hunting out of spies and informers in Korakum. Now all are hanged."

At these words, Mr. Hampton arose and stepped forth, at the same time
beckoning his companions to do likewise. Deepest astonishment was
visible on the faces of the four Athensians at this unexpected sight.

"Who among you speaks French, Spanish or English?" Mr. Hampton asked.
"Or Arabic, either?" he added, thinking of Ali. If Amrath had spoken
truly in saying the revolutionaries all were young men of the priest
clan who had been sent abroad in the world to study among various
civilized peoples, it was possible that one of the four was capable of
conducting the necessary conversation in a language more familiar to Mr.
Hampton than Athensian.

Jepthah smiled.

"You are an Englishman?" he asked, in English with only a trace of
accent. "I have served in the Egyptian armies of England and know the
language, perhaps a trifle better than you, sir"--with a deprecatory
bow--"know our native tongue."

"Not English," said Mr. Hampton smiling, "but American. However, our
tongue is the same and I'm mighty glad to meet a man who can speak it."

Jepthah bowed. Politeness among these men seemed unfailing.

"If you are a friend of Amrath," he said, "we can speak plainly. We are
on an important mission and must not delay. What message does he send,
and where is he? We feared he had been done away with."

"He was attacked by Athensian soldiers," said Mr. Hampton, coming at
once to the point, "and left for dead at a desert oasis six days journey
distant to the north. We found him and nursed him back to life. He was
still weak and could not move, but was out of danger, when we left him a
week ago. His message to you was that you should help us. My son," he
added simply, "has been captured by Athensian raiders, and from what
Amrath told us we fear he is destined to take part in the Sacrificial
Games. We are here to attempt his rescue."

Jepthah looked along the line.

"Ten men to assail Athensi," he said. "You are very brave."

Mr. Hampton flushed.

"We love him," he said. "He is a great athlete and undoubtedly has been
captured for the Games. At Amrath's direction we came directly to this
point in order to arrive in advance of my son's captors who, said
Amrath, would take a circuitous course in order to touch at three water
holes. My son's captors were only eight or ten in number, we believe.
And we feel certain we have arrived ahead of them. Here we lay in ambush
since before dawn, when by chance as you passed I heard repeated the
names of those true men Amrath told me to seek in Korakum, and so
appealed to you."

During the course of this recital, Jepthah's face betrayed increasing
excitement, and barely had Mr. Hampton concluded than the young
Athensian turned to his companions and began translating in their own
language at a rate far too rapid for Mr. Hampton to follow.

Immediately Shedrach and Shilluk whirled their horses and started down
the Great Road at a breakneck pace.

"They go to tell our captain, Amanassar, what you have said," explained
Jepthah, again falling into English and addressing Mr. Hampton. "If the
troop has not yet debouched into the desert, he will turn back and in
the pass will await your son's captors."

"What if the troop did get into the desert, and happened to be seen by
the raiders," asked Jack, anxiously. "Would the fellows who hold Bob
prisoner realize your people are enemies and flee?"

"I do not know," said Jepthah. "Revolution has been brewing for long,
but this is our first open move. Yesterday we hung all spies and
informers among us. Athensi is unapproachable by this direction except
through a subterranean river, which is heavily guarded. Today we are on
our way to approach the city through the mountains by another entrance
over the Mountain Wall. We plan to raise the standard of revolt against
the priests and their Janissaries, among the peasants and country
people."




                              CHAPTER XVI.
                         REVOLT OF THE EXILES.


The noonday heat was oppressive in the open, and the faces of the two
Athensians glistened with perspiration as they sat their horses in the
sun. Mr. Hampton noting this, suggested they enter the shade of the
grove on the plateau pending the return of their comrades, and Amonasis
and Jepthah willingly spurred their horses up the sloping terrace. Eager
to be of service, Jack hastened to the rear of the plateau, returning
presently with a bucket of clear cold spring water which proved very
refreshing to the travellers.

"You found an admirable place for an ambush," remarked Jepthah, looking
about approvingly. "I have not been here before. Korakum is a
considerable distance up the Great Road, and we seldom have come down
here as it was unnecessary, we thought, to keep watch on the desert.
Only as we passed through, in order to gain the other trail and labor on
repairing it, have we gone up and down."

"Then you did not know of the passage of the raiding party?" asked Jack,
surprised. "Does that mean they left Athensi over the other road of
which you speak?"

"I don't know," confessed Jepthah, frankly. "We have been questioning
ourselves as to whether the spies among our number betrayed our work on
that trail to the authorities. The men who captured your friend may have
gone into the Great Desert over that trail. Again, however, they may
have passed down this road without our being aware of it. As you may see
for yourselves some day, the valley in which Korakum lies is of great
extent, and the ruined city where we dwell lies some distance from the
subterranean river by which men are accustomed to come and go from
Athensi. This party may have passed to the outside quite easily without
being seen."

"Have you been living long at Korakum?" asked Mr. Hampton. "Your friend,
Amrath," he explained, "told me that in retaliation for sheltering and
speeding the departure of my friend, Professor Souchard, a number of
years ago, the kindly exiles of Korakum were slain by the Athensian
authorities."

Jepthah threw up his hands in a gesture of anger.

"That happened before our arrival, before the arrival of any of us in
this band," he said. "Every year a new levy of youth of the priest clan
is sent into the world to gain knowledge. Each man is bound by the most
solemn of oaths not to betray knowledge of his country and to return on
a certain day.

"I have heard the story of your friend, and of the exiles who were
punished with death for permitting his escape. It was horrible. I and my
friends were among those who returned home since that occurrence, and
because of our criticism of the practises of our people, we were exiled
to Korakum."

"But I saw some middle-aged men in the troop of Captain Amanassar,"
protested Frank, taking a voice in the discussion.

Jepthah turned toward him, as he answered:

"That is true. They were men living quietly in Athensi who rebelled at
the slaughter of the exiles who aided Professor Souchard. That act of
barbarism and ruthlessness completed their distaste for life under the
Oligarchs, and they fled to join us younger men who were exiled as a
disciplinary measure. Ah," he said, bitterly, "we have been steeped in
the traditions of our caste which reach back into ages more remote than
any recorded history known to you. To break away from those caste
instincts and traditions is very difficult. But we cannot stand the
Oligarchs any longer."

"Why do you not invite outside aid?" asked Jack, who had listened with
intense interest.

Jepthah shrugged, and his face darkened.

"My dear sir," he replied, "if you know the history of Africa of today,
you will realize why we have not done so. Outside of our own country,
the existence of which is not even suspected by the great mass of
humanity, although a few savants like Professor Souchard and a few
adventurers and slave traders have some knowledge of it, what portions
of all this vast continent retain their freedom today? Egypt? Morocco?
Algiers? Tunis? Tripoli? All ruled by interlopers. South Africa, Central
Africa, the West Coast, the East Coast, all are subservient to one or
other of the Powers. Only Abyssinia of the ancient states retains its
independence. Liberia is a free country, too, but a republic created by
Negro slaves and supported by your land."

"But the tribes of the Great Desert," suggested Ali, speaking for the
first time.

"Yes, you Arab and Berber nomads know how to retain your freedom," said
Jepthah, tolerantly. "But if you dwelt in a rich and fertile land such
as lies within this vast ring of mountain, the conquerors would not let
you retain your independence. Your desert protects your oases from their
grasp.

"No," he added, after a moment's pause, "we have no desire to bring
outsiders in to our aid, we revolutionaries, knowing too well what that
would mean. You see"--with a sad smile--"we have only recently returned
from your own world, and our opinion of the disinterestedness of your
governments is not the highest. No, we prefer to drive out the Oligarchs
ourselves and then--with a stable government established, democratic and
just, to invite civilization to bring us its benefits and leave its
evils behind."

Mr. Hampton nodded emphatic agreement.

"That is, indeed, the wise thing to do," he said. "And now that we are
on the scene, if we can be of any help whatsoever, you have only to
command us. The cause in which you fight is, so far as I can see, one
worth enlisting to support. What you have said interests me profoundly,
and I would like to talk with you and your friends more at length about
this mysterious land of yours. But, if I am not mistaken, here come your
friends returning, and in haste, too."

The clatter of rapid hoofbeats ascending the Great Road from the
direction of the desert was dear to all.

"They'll wonder what has become of us," said Jepthah. "I'll give them a
call."

Rising, he put one hand over his mouth and emitted a peculiar call,
obviously an understood signal, for immediately the sound of hoofbeats
ceased as the horses came abreast of the plateau. Then the screen of
bushes parted and Shilluk and Shedrach pushed their way into the grassy
enclosure toward the rear to which the party had retired.

A rapid conversation between Shilluk and Jepthah, carried on in
Athensian, followed. Turning to Mr. Hampton, Jepthah betrayed an anxious
face.

"I'll not seek to hide your son's danger from you," he said. "Shilluk
reports that before he could reach Captain Amanassar the latter had
sighted a party of horsemen in the distance, apparently heading for the
other entrance through the Great Mountain Wall. He set out in pursuit at
once with a score of our number comprising the best mounted, leaving the
others to follow more at leisure. This Shilluk learned from the main
body, which already proceeded a short distance into the desert, but
which he overtook."

"But, Bob--" began Mr. Hampton, when Jepthah interrupted.

"I know, sir, how you must feel," he said, sympathetically. "Yet Captain
Amanassar will do his utmost to aid, just as if he knew the
circumstances of your son's captivity. You see, from the main body
Shilluk gathered that Captain Amanassar believed our troop had been
sighted, and that it was on that account the raiders headed for the
other road. He recognized them as of the Janissaries, and will do his
utmost to cut them off to prevent word of our approach reaching Athensi.
Not but what the Oligarchs, whose spies riddle the country, will hear
soon enough," he concluded bitterly.

"Mr. Hampton, you've just got to let us go at once," broke in Frank.
"I'll go crazy if I don't have a hand in this. Poor old Bob." He was
unable to continue because of a lump that rose in his throat.

The elder man's hand dropped on his shoulder.

"What do you say?" he asked Jepthah. "Won't your friends be surprised if
these young fellows come dashing along on camels?"

"If you are willing," said Jepthah, "you shall all come. Shilluk and
Shedrach already have prepared some of our comrades for sight of your
party, and they will have spread the word. All will be eager to have
your aid, and equally eager to aid your son if possible. We heartily
detest the holding of the Sacrificial Games, which is a part of the
detestable religious practices kept alive by the Oligarchs. Come, then,
at once. Leave your equipment here."

"Quick, Jack," cried Frank.

His comrade nodded. They were first of the troop to mount, and soon were
flying down the Great Road with the four Athensians, their camels moving
at a pace that astonished the horsemen. Not far behind them came Mr.
Hampton, Ali and the Arabs.




                             CHAPTER XVII.
                        THE FIGHT FOR THE PASS.


When they emerged from the Great Road, the Great Desert lay shimmering
before them. Under the sun, standing directly overhead in a cloudless
sky, the irregular floor of sand stretching illimitably in three
directions like gently-rolling waves of the sea arrested in motion,
seemed radiating heat waves like the top of a stove.

In the fourth direction, at their backs, stretched away on either hand
the Great Mountain Wall. For the first time by daylight they had a good
look at it, and involuntarily both Jack and Frank drew in their breaths
at the sight.

Steep, precipitous, verdureless, the mountains rose in great masses of
rock directly out of the sand, just as the Pillars of Hercules, guarding
the Strait of Gibraltar, rise out of the sea at the northwestern
extremity of the African continent. The sand was like a sea dashing
vainly against these gigantic masses of rock.

One mountain overlapped another, so that only narrow, unscalable clefts
broke the face of this tremendous bulwark. Truly, it was a Mountain
Wall. Ahead this wall stretched to the horizon, and, looking over their
shoulders, the boys saw no end in sight behind them. A full two thousand
feet towered the serrated summits, jagged and sawtoothed, forming
grotesque shapes that resembled crumbling turrets and, in some
instances, crouching animals of gigantic proportions.

The previous evening, before the light failed, and while they still were
hours away, they had been able to see that beyond this wall lay a
tumbled mass of mountain tops rising higher and higher to a lofty summit
far to the south, which Mr. Hampton had estimated at 14,000 or 15,000
feet in height. Apparently, then, the mountain country was of
considerable extent, with many interior valleys and plateaus.

Somewhere behind that Mountain Wall and in the heart of that great
upland country lay mysterious Athensi, while through the rich valley and
plateaus were scattered the dwellings of the peasants comprising the
last of a prehistoric white race whence had sprung, if Professor
Souchard was correct, all mankind.

But to these reflections Jack and Frank, unable because they rode close
to the foot of the Mountain Wall and could not see the peaks of the
country behind it, gave only passing reflection. Almost immediately on
debouching into the desert they had discerned far in the distance a
number of tiny figures drawing away from them to the west. These
undoubtedly were the horsemen of the rear guard of Captain Amanassar's
rebel troop.

"Come on, Jack," yelled Frank, "I'll race you for them."

Jack yelled agreement, and away went the two boys, jouncing and bumping
in the awkward camel saddles, their animals eating up the ground, while
beside them galloped the four young Athensians. The boys had all they
could do to hold on, but once or twice managed to steal a glance over
their shoulders which assured them Mr. Hampton, Ali and the Arabs were
close in the rear.

The Athensian revolutionaries ahead were riding at a brisk pace and the
distance between decreased slowly. Yet steadily the boys overhauled them
until, at the end of a half hour, they were up with the rear ranks. That
term, however, is a misnomer, as the revolutionaries had broken ranks
and were riding without formation.

Jepthah brought his horse alongside Frank's camel as they drew near and,
when the rearmost revolutionaries turned to glance back inquiringly, he
called to them in their own tongue. They nodded, and several waved their
hands to the boys in airy salute.

"Follow me. Let me take the lead," Jepthah called in English to Frank
and Jack. Then he and Amonasis, putting their horses together, passed
through the loose ranks of the revolutionaries, with Jack and Frank on
their swaying camels close behind. Shilluk and Shedrach, following a
quick interchange of words in Athensian with Jepthah, fell back to await
the approach of Mr. Hampton and the Arabs.

As the boys rode headlong among the revolutionaries, who parted to let
them pass, many curious glances were thrown at them. Several times
Jepthah or Amonasis called out in Athensian, evidently spreading the
announcement of their identity, and frequent salutes were given. As for
Jack and Frank, however, they were too busy clinging to their swaying
camels to accord acknowledgment in kind.

Once through the ranks of the revolutionaries, the boys began glancing
anxiously ahead to catch sight of Captain Amanassar's troop and,
perhaps, of the Janissaries with Bob. But neither group was in sight.
Was it possible, they asked themselves, that already the pursuit had
drawn so far ahead as to be lost to view? Or had the two parties already
entered the break in the Mountain Wall of which they had heard so much?

Frank could not stand the anxiety without attempting to obtain an answer
to these questions and called to Jepthah. After repeated attempts, he
managed to obtain the latter's attention. Jepthah who had drawn
considerably ahead, pulled up his horse until Frank came alongside. The
latter shouted his queries, and received a shake of the head in reply.

"Not out of sight down the desert," cried Jepthah. "But into the old
trail. Follow swiftly. We may be needed."

Before he could spur his horse ahead, Frank called another question:

"Do you mean the Janissaries reached the pass ahead of your men?"

His voice was filled with horror.

"I'm afraid so," replied Jepthah, with a look of sympathy. "Come on. All
is not lost yet."

Leaning forward until he lay on the neck of his splendid horse, he
whispered into its ear. The animal already running swiftly seemed to
leap ahead, gaining on Amonasis flying along in the lead.

Jack had drawn close during this brief conversation carried on in
shouts, and had gathered the import of Jepthah's remarks.

"Come on, Frank, come on," he shouted. "Never say die."

Faster and faster under shouts and blows ran the camels, and for a time
the boys had all they could do to retain their precarious seats. For a
time Jepthah set their course well out into the desert, in order to
avoid the jumbled mass of rocks and boulders lying at the foot of the
Mountain Wall. But presently he headed again toward the great bulwark
and the boys, following him, saw ahead a break appear in the wall.

Narrower than the pass through which ran the Great Road, it seemed as
their eyes pierced deeper with each forward lurch of the camels that it
was choked with fallen boulders over which it would be difficult to make
their way. But even as this thought entered their minds, and while yet
they were a matter of a hundred yards distant, with Jepthah and Amonasis
somewhat nearer, around the nearest bend of this pass came a fleeing
mass of horsemen.

Down toward the desert leaped the horses, surefooted as goats, over the
mass of boulders and debris. Involuntarily, Frank and Jack pulled up
their camels, whose great padded hoofs slid in the sand as they braced
their legs to come to a halt. Then they saw Jepthah turn in his saddle
and wave wildly for them to approach, after which he and Amonasis flung
themselves forward, unlimbering their rifles as they ran.

At the same time, from beyond the bend in the pass, came the rattle of
rifles, and this time three horses with empty saddles and a fourth
dragging the body of a fallen man whose foot was caught in the saddle
and who bumped sickeningly over the rocks, came down the rock-choked
pass.

In one illuminating flash the meaning of the situation appeared to Jack.
Shouting across the gap separating him from Frank, racing beside him, he
called:

"Rebels followed 'em into the pass and were ambushed, I'll bet."

Frank made no answer. His face was white. Undoubtedly, he thought, Jack
had read the situation aright. Then what of Bob? Had he been killed in
the fighting? Or had his captors escaped with him into the interior?

Another man and another tumbled down the pass, his horse taking the
rocks at a sickening pace, until ten were gathered at the foot, where
Jepthah and Amonasis could be seen rallying them. Just as Frank and Jack
gained the group, one more revolutionary turned the bend, from beyond
which the sound of firing had drawn closer, and came down the pass. The
boys gasped in mingled admiration of his daring horsemanship and fear
for him.

He sat loosely in his saddle, the reins lying on his horse's neck,
leaving the sagacious animal to pick his own way over the rock-strewn
course. Half-turned about, he held rifle to shoulder. Not thirty feet
behind him another horseman suddenly appeared rounding the sharp turn in
the pass, and the rifle of the revolutionary cracked and almost
simultaneously the other pitched from his saddle.

A cheer went up from those in the plain, and with a wave of the hand in
acknowledgment, the lone revolutionary continued the descent.

"Who is he?" asked Jack of Jepthah, beside whom he had pulled up his
camel.

"Captain Amanassar on his wonder horse, Sheelah," replied the other in a
tone of pride. "Here they come. Give them a volley," he added, and
raising his voice shouted a similar command in Athensian.

Only five of the Athensians carried rifles, and none was a modern arm.
They were long barrelled Arab weapons. However, with these they shot
over the head of Captain Amanassar, while their comrades loosed a flight
of arrows, and Jack, Frank, Jepthah and Amonasis also joined in. The
repeaters of the boys worked deadly execution, and the head of a
tumultuous mass of Athensian Janissaries which, pushed forward
apparently by the weight of numbers in the rear, swept around the bend
in the pass on the heels of the fallen leader whom Captain Amanassar had
shot down, melted away. Men and horses fell in a writhing heap on the
narrow, rock-strewn causeway, and effectually blocked the advance of
those behind.

Bewildering events succeeded almost too rapid, in fact, for Jack and
Frank to follow. Captain Amanassar took charge of the situation,
shouting his orders in Athensian which the boys could not understand.
They saw him cast a surprised, frowning glance at them, and turn to
Jepthah who pushed to his side and spoke rapidly. Then his eyes, which
had not been taken from them, lighted up with a rare smile, and across
the intervening horsemen, Jack and Frank saw him lift his hand to his
forehead in a semi-formal salute.

After that, for a time, in the press of more urgent matters, he paid
them no attention. Mr. Hampton with his Arabs arrived, and sharp on
their heels the vanguard of the main body of revolutionaries, with the
others continually spurring forward. Rapidly the dimensions of the force
at the foot of the pass grew.

Mr. Hampton withdrew to one side with the boys and his Arabs, and Jack
and Frank in broken sentences recounted what had occurred before his
arrival. All watched the disposition Captain Amanassar was making of his
forces, seeing groups of horsemen detach themselves from the main body
and go whirling away to the westward along the Great Mountain Wall,
while those remaining dismounted and handed over their horses to a small
guard.

"I must see about this," said Mr. Hampton. "It looks as if they planned
to attempt to retake the pass, probably attacking afoot directly while
others go to hunt paths up over the rocks which will permit them to take
the enemy in the rear. Perhaps we can be of help. Let everybody await me
here."

So saying he went forward toward Captain Amanassar who, like the others,
had dismounted, and by whose side stood Jepthah. The boys saw Mr.
Hampton join the two Athensian revolutionaries in conversation and,
after a vigorous interchange of words, turn and make his way back to
them.

"It is as I suspected," he reported. "So I have offered to take over the
duty of looking after their horses, which will permit all their forces
to engage. Also, we are going to lend our repeaters to the
revolutionaries, as Jepthah says there are a number of men in the ranks
familiar with their use. Here they come now to receive them," he added,
as Jepthah advanced with two others to receive the rifles of Mr. Hampton
and the boys. "So hand them over, along with your ammunition."

"But Mr. Hampton," protested Frank, "I want to have a hand. Think of old
Bob." His voice broke.

"I know," said the older man, kindly. "But the pass must be forced if
the revolutionaries are to gain the interior. The raiders, they tell me,
were met here by a force of two score Athensian Janissaries, who beat
off Captain Amanassar's first attack. If we are to be of any help to
Bob, we must let these men clear the way. And in doing that, you might
lose your life uselessly, if you were to take active part in the attack.
Come, now, hand over your rifle."

Reluctantly, Frank and Jack consented, after which with the Arabs they
went to relieve the horse guard. Mr. Hampton, however, joined Captain
Amanassar, who stayed in the plain directing operations.




                             CHAPTER XVIII.
                              A DARK HOUR.


Much of the fight for possession of the gateway to the pass was out of
sight of the boys. For a time, they could see the figures of the
dismounted revolutionaries creeping over the rocky road, hugging the
walls, until they reached the barrier of fallen Janissaries and horses.

Across this barrier there flashed a continuous fire of weapons for some
time, with no advantage to either side, so far as was apparent to those
left in the plain.

Then a new element entered the situation with a distant sound of rifle
fire, as the party of revolutionaries who had been sent to the west came
into action at the rear of the Janissaries. These revolutionaries, the
boys later learned, had clambered like goats up the face of the cliff
and gained a position on the rocky western wall of the pass, from which
they were enabled to assail the Janissaries in the rear.

A sudden burst of cheering in the distance was followed by the swarming
of the revolutionaries in the pass across the wall of dead and wounded.
Man after man disappeared without opposition, passing across the fallen
and vanishing into the pass beyond the bend. Then for some time the
sound of firing continued, growing ever more distant, until it no longer
came back to those below.

Once more stillness descended in the hot desert and the narrow pass, now
lying in shadow as the sun wheeled to the west and the steep western
wall of rock cut off its rays. Only the horses, the Arabs on camel back
circling slowly about them, Captain Amanassar, Jepthah and Mr. Hampton,
three tiny figures afoot at the base of the pass, and the dead,
remained.

Eaten up with anxiety as to the fate of Bob, a prisoner in the midst of
the fighting so far as they knew, the boys no longer could contain their
impatience. They saw a revolutionary return down the pass, making his
way over the barrier of men and horses at the bend, picking a careful
passage over the rocks below, and moving to report to Captain Amanassar.

"Come on, Jack, let's hear what he has to say," begged Frank. "I know
your Dad told us to stay here, but the Arabs can look after the horses
and I'll go crazy if I don't do something."

Jack felt pretty nearly as cut up over the failure to rescue Bob, as did
his comrade, and nodded in sympathy.

"All right," he said. "We'll go up and ask Dad what the messenger
reports. Hardly likely, though, that he has any word of Bob."

When they reached Mr. Hampton's side, the messenger already had made his
report. Jepthah, interpreting the reason for their approach, turned to
them with a grave face.

"There is no sign of your comrade," he said. "I asked the messenger
particularly. He is not among either the prisoners or the fallen. Some
of the Janissaries escaped, and evidently they have borne him with them.
They will make their way to Athensi. We cannot stop them. They have
broken down a bridge which we recently rebuilt across a deep chasm and
for a time our advance is held up. Athensi lies many miles away,
however, and we shall be able to gain the interior before fresh forces
can be thrown against us. The Sacrificial Games still are more than a
month away, and in the meantime something can be done toward effecting a
rescue."

With this, Jepthah returned to Captain Amanassar's side, while Mr.
Hampton joined the boys.

He reported that Captain Amanassar was going forward to join the
revolutionaries, a portion of whom would be sent back to clear the pass
so that the horses could be taken into the mountains. Aware now that
betrayal of their plans by spies of the Oligarchy in their ranks had
been more general than supposed, Captain Amanassar found it necessary to
re-arrange his campaign.

Originally, he had intended entirely to abandon Korakum. Its peculiar
position, in an outer valley, leading only by the Great Road to the
desert and by the subterranean river to Athensi, made it a poor basis of
operations from which to conduct a revolution among the countrymen of
the many interior valleys and plateaus against the central authority of
the Oligarchy. All this he and Jepthah had explained to Mr. Hampton. By
placing a guard over the pass just captured, the revolutionaries would
be able to prevent any forces sent out from Athensi via the river and
Korakum from attacking them in the rear.

A chance suggestion made by Mr. Hampton had taken root. If the spies, as
now was apparent, had betrayed the revolutionists' plans, then the
Oligarchs would not be looking for attack from Korakum along the
subterranean river. Therefore, Mr. Hampton had suggested the possibility
of making such an attack at a later date in conjunction with an attack
in force from the field.

"They expect," he told the boys, "to be able to raise a considerable
army of ten thousand or more countrymen, for the country groans under
the misrule of the Oligarchs and is ripe for revolution. It awaits only
the coming of a leader supported by determined captains, and in Captain
Amanassar and his hundred men I feel certain such leaders have been
found."

Accordingly, it had been decided not to abandon Korakum entirely, but to
place a guard over the subterranean river for the purpose of capturing
any Janissaries who might negotiate its passage from the interior, and
of retaining control of that underground water thoroughfare to Athensi.

Mr. Hampton, the boys and the Arabs were to form a portion of this
guard, as Jack's father had assured Captain Amanassar he would
co-operate with the revolutionaries, at least as long as there was a
possibility of effecting Bob's rescue.

"It is pretty certain," he explained, "that Bob was captured to
participate in the Sacrificial Games. Such being the case, his life will
be jealously guarded until the time of the Games arrives. That gives us
a full month more. Certainly, some way of saving him will develop in
that time. Perhaps, the revolutionists will be successful and then, of
course, the men destined to participate in the Games will be set free."

Jack and Frank could do nothing except acquiesce gloomingly.

"But think of Bob's feelings all that time, as he sees the end draw
nearer with no word of hope from us," said Frank.

"Maybe," added Jack "when he is in prison he will be able to rig up his
radio set and we can send him a message of comfort, something to tell
him we are working to rescue him."

"Maybe," said Frank, sadly. "But we wouldn't know whether he got our
message or not. Well, come on. If it's back to Korakum, we'll finish
putting the radio apparatus in shape."

Side by side, silent, each immersed in sad thoughts, Jack and Frank led
the way on the return, followed by their companions.




                              CHAPTER XIX.
                              AT LOW EBB.


Now began a period of waiting, during which the boys saw little of
Jepthah. A guard of ten revolutionists was sent back to Korakum to
supplement their own force under command of a cheery young man named
Horeb who, like Jepthah, had served in the British Sudanese army, and
had a good command of English. Thus the two parties had a common medium
of expression. From Horeb, who each day sent a messenger to the main
body, they received fragmentary accounts of the progress of events in
the field.

Things were going well with the revolutionists, they learned. The
Janissaries, numbering 5,000, so far had failed to take the field
against them, for what reason was not known. In the meantime, Captain
Amanassar was rallying the sturdy peasants of the valleys and plateaus
and the herders of the mountains to his standard. He had advanced twenty
miles into the mountains in three days and already a force of fifteen
hundred men had assembled. He lay at the village of Sharpath, on a high
plateau, well guarded against surprise, and intended to maintain this
position for a week or more while the countrymen continued to come in.

Sharpath, the boys were told, stood in the center of a broad plateau
comprising one of the richest agricultural districts of the mountain
country and the road approaching it from Athensi, along which the
Janissaries would have to move to attack, passed through a deep gorge
which already was in possession of the revolutionists.

"All right for them," muttered Frank. "But the longer they stay there,
the nearer draws the day of the Sacrificial Games. I'm worried about
Bob, Jack, and I want to do something. Can't you put your mind on it.
I've been thinking of ways and means until I feel as if I were growing
insane."

Frank was seated at the table on which the radio sending apparatus had
been set up in the little grove off the Great Road where originally they
had taken shelter. When surprised by the revolutionists he and Jack had
left their work of putting the radio into shape uncompleted. Since their
return they had been wandering over the ruins of Korakum for two days
without again thinking of the radio, lost in admiration of this ancient
city--the oldest, undoubtedly, in the world.

Only a few of the buildings had survived the ravages of thousands of
years, here a temple, there a palace. They jutted up among the vegetable
gardens of the exiles, and, when the boys expressed to Horeb their
surprise at not finding even a trace of other ruins, he shrugged and
smiled.

"The houses of the common people were not builded of enduring
materials," he said. "It is so in Athensi today. The common people live
in mud huts with wattled walls and thatched roofs, little better than
those of African savages. But the temples and palaces of Athensi, ah!"
He made a gesture indicative of his despair at attempting to
characterize them.

"Some day soon, I hope, you shall see for yourselves," he added. "And it
was so in Korakum. These temples and palaces, as you can see, were built
of granite hewn from the mountains, and are of immense solidity. Even
they have fallen into ruins now, as you see, for this city was founded a
full thousand years before the first of our people entered Egypt.

"We came from the great island continent of Atlantis, lying west of the
Pillars of Hercules, west of the Strait of Gibraltar, and our city was
the first Atlantean colony. Our people pushed south along the African
coast, into the Gulf of Guinea, up the Niger river, and thence eastward.
Here was their first permanent settlement, and Korakum was a flourishing
capital before we dreamed of entering Egypt. History?" said he. "Wait
until the world receives the translations of the stories in the Library
of Athensi. It is the history of the world before the Flood submerged
Atlantis, giving rise to all the legendary stories of the Flood which
persist in the literature of all people. It is the history of a mightier
civilization, extending farther back into the years, than your wildest
dreamers ever conjured out of their imaginations."

Through echoing stone halls of vast breadth and height, up stone
stairways, under gaping roofs, for two days, the boys had wandered at
will, staring at the shell of that ancient civilization of which Horeb
spoke, marvelling at the tremendous labor involved in these buildings,
involuntarily dropping their voices to a whisper in the presence of the
ghosts of uncounted centuries.

But now, on the third day, having seen all there was to see and not
being scientists who could pore forever over the meaning of faded and
worn inscriptions found here and there upon a fallen block of stone,
they were back in the grove, and Frank was seated at the radio and
voicing his desire for action, immediate action, looking to the rescue
of his chum.

This apparatus, devised by the boys working in conjunction in their home
laboratories at the Temple and Hampton country homes, adjoining each
other, on Long Island, was a duplex sending and receiving station. In it
they had departed from the accepted methods of duplex operation, of
which the best known is that of Marconi, regulated by a receiver coupled
to the coils of a transmitting antenna and a balancing antenna, by means
of which one signal may be cut out completely while another is retained
undiminished, thus insuring reception and transmission simultaneously.

Instead, they had worked out a system whereby the voice exercised full
control. When speech was not being used, the set was receptive to
messages from other points. But the moment one began to speak, a
sluggish contact device consisting of mercury in capillary tube was
closed by the vocal vibrations and the set at once thrown into
transmission. This controlling device was located in the microphone
transmitter, and that it had escaped destruction in the vandalism
practised on the set by Professor Souchard's murderers was little short
of a miracle.

After voicing his request that Jack put his mind to work to evolve some
plan for rescuing Bob, Frank picked up the headphones and idly clasped
them to his ears, and sat silent, gloomily regarding the instruments on
the table, although in reality not seeing them. By some chain of
thought, he was once more back on Long Island, standing on the lawn of
the Temple home, and watching for Della to emerge from the doorway. It
seemed to him, so powerful was the impression, that he had arrived to
tell her Bob had been slain in the Sacrificial Games in Athensi, and----

"Jack," he cried suddenly, in so startled and excited a voice that his
chum, sprawled on the grass, leaped to his feet. "My--my--"

Words failed him, his face grew white as a sheet, and his eyes seemed
actually to bulge out of their sockets.

"What is it?" demanded Jack, anxiously. "Are you sick? Speak. Tell me
what's the matter."

Frank could only wave his hands feebly and shake his head.

Then he seemed to change into new life under Jack's gaze. Color returned
to his cheeks, his eyes grew bright and joyful, and, leaning forward, he
drew the telephone transmitter toward him and began to speak. In Jack's
mind, stupefaction succeeded bewilderment as he listened.




                              CHAPTER XX.
                         AN OLD FRIEND APPEARS.


"Mr. Hampton isn't here, but this is one of his men speaking," Jack
heard Frank say.

As in a daze, Jack stood open-mouthed while Frank continued:

"What's that? Roy Stone?"

Frank's voice was joyful, unbelieving.

"I can't believe it's you, Stone. I just can't," Frank continued. "This
is Frank Merrick speaking. But how in the world? Where did you come
from? Wait a minute, wait a minute."

He turned to Jack.

"It's Roy Stone," he cried. "Remember?"

Did Jack remember? A flood of memory engulfed him. All the details of
that fight in the cave a good four years before came sweeping back. Mr.
Hampton had been held prisoner by Mexican rebels in a stronghold in Old
Sonora, across the border from New Mexico. The rebels also had stolen
the airplane which was the pride of Bob and Frank, who were its joint
owners. Setting out with Tom Bodine, an ex-cowboy, to rescue Jack's
father, the three boys had put up one night in a mountain cave to which
Tom led them.

They found it outfitted as a radio station by the Mexican rebels.
Shortly after their arrival, one of the Mexicans named Morales, a German
named Von Arnheim, who was stirring up trouble on the border in the hope
of embroiling the United States in war, and a young American aviator
named Roy Stone, a stormy petrel, a soldier of fortune, who had cast in
his lot with the rebels, arrived. More to the point, they arrived in the
airplane stolen from the boys.

In the fight which followed in the dark cave, the boys and Tom Bodine
had won. The three others had been made prisoners. Learning their story
and realizing the Mexican rebels were being employed as pawns by Von
Arnheim, to the detriment of his own country, the American Stone had
swung his allegiance to the boys and had been of material aid in
effecting the subsequent rescue of Mr. Hampton.

All this came back to Jack in a flash, and he wondered if he had heard
Frank aright. How in the world could Frank be speaking with Roy Stone?
Frank was listening in wrapt attention to whatever message was coming
over the radio, and Jack could not bear the suspense. He grasped Frank
by an arm.

"Are you dreaming?" he asked. "Tell me what all this is about?"

"Wait a minute, Roy, wait a minute," Frank again said, speaking into the
telephone transmitter. "Jack Hampton is here and he thinks I'm going
crazy." Then he turned to Jack with shining eyes.

"It's Roy Stone all right enough," he said. "He's flying for the Spanish
government, which is having one of its numerous wars with the Riff
tribesmen of Morocco. At least, he'd been flying for the Spaniards but
decided to quit fighting the Moors who had a better right to their own
country than the Spaniards. Now he is crossing the desert to Abyssinia,
where somebody told him there's a war he could have a hand in. Anyway
that's what I gather. He was forced to descend at the Oasis Aiz-Or, and
there found Amrath who told him of us. He recognized the names and wants
to know if he can be of help."

"Can be of help?" shrieked Jack. Seizing the transmitter he called into
it:

"Hello, old scout. This is Jack Hampton. Come a-flying. You'll be an
angel from heaven."

Releasing the transmitter, Jack darted away, calling to Frank:

"Keep him till I get back. I'm going to round up Dad."

Mr. Hampton was not in sight in the grove, and Jack dashed out into the
hot sunshine and up the Great Road toward Korakum. Despite the
oppressive heat in the pass, he ran as if he had wings on his heels. So
great was his sense of elation at finding an airplane and a friendly
pilot near enough to be of aid, though just how that aid could be
employed he had not yet decided, that he would have been able to run all
the way to Korakum without feeling fatigue.

As matters turned out, however, that was unnecessary. Before he had gone
far, Jack saw Mr. Hampton appear in sight on camel-back. He waved an arm
frantically for his father to hurry, and the latter, alarmed, put his
animal to a trot.

"What's happened now?" he called, as he drew nearer.

"Hurry along to the grove, Dad," panted Jack. "I'll follow as fast as I
can. The radio's working and we've got an angel on the wireless."

"Jack," demanded his father, "have you gone crazy? Out here in this sun
without your helmet, too."

"Crazy, yes, Dad," Jack laughed merrily, "crazy with joy. Now do hurry
along. Frank's got word for you, and someone for you to talk with over
the radio who'll give you your best hour for many a day. No, I'm all
right, really. Just go on to the grove."

Seeing that Jack was really serious, despite his exuberance, Mr. Hampton
wonderingly continued. When Jack arrived later he found his father
seated at the phone.

"He's talking to Amrath now," said Frank. "Hear him, speaking French."

Drawing Jack to a sufficient distance so that their conversation would
not disturb Mr. Hampton, Frank explained. Only a short time before, Roy
Stone had arrived at the oasis where, as Frank had earlier told Jack, he
was hospitably received by Amrath who had recovered his strength in a
considerable measure. Learning he was an American, Amrath had spoken of
the other Americans who recently stayed at the oasis. Then, as Stone
recognized Mr. Hampton's name, the whole story, even to the kidnapping
of Bob, and the setting out of the rescue party, had been related to
him.

At once he had gone to his airplane, which had been forced to descend
because of a leak in the radiator, and had tuned up his radio and
started calling for Mr. Hampton on the slim chance that he would be able
to reach his old-time friends.

"If he hadn't heard from us," added Frank, "he intended to get
directions from Amrath for finding Korakum and fly south in search of
us."

"Luckily, he did get us," said Jack. "Think Frank. With an airplane we
may be able to work out some plan of getting into Athensi and rescuing
Bob."

"That's just what I am thinking of," said Frank. "And what I was
thinking of all the time."

"Dad has finished talking to Amrath, I reckon," Jack pointed out. "Let's
hear what he has to say."

They made their way to the side of Mr. Hampton who, having taken the
headphones from his ears, sat with his head bowed into his hands.

Jack laid a hand on his father's shoulder, and the older man lifted a
face unashamedly wet with tears.

"Why--why--" began Jack, startled.

His father smiled.

"It's all right, Jack," he said. "Only I have been so worried about Bob.
And this sudden discovery of Roy Stone in this part of the world, and
with an airplane, seems like an answer to prayer. If there is any way of
saving Bob, I begin to believe it must be by airplane, because the
campaign of the revolutionists will take too long. Athensi may fall in
time, but the Sacrificial Games would be held long before the city's
capitulation. And that would mean----"

"I know Dad." Jack's hand gripped his father's shoulder hard.

"Well, things look immeasurably brighter now," Mr. Hampton added. "And
for the revolutionists, too. Stone is a quixotic fellow or he would not
have left the Spanish service because he thought the Moors were
receiving a bad deal. It may be, he will be glad to help the
revolutionists. And an airplane could certainly be of use to them. But,
first of all, he said he would do his best to help rescue Bob.

"They'll be here at sunset. The oasis is three hundred miles away, but
what it took us six days to travel, Stone can cover in three hours."

"They?" asked Frank.

"Yes, Amrath is sufficiently recovered to come, too. Now I must go and
tell Horeb. He'll be glad. Amrath is a big man among these
revolutionists."




                              CHAPTER XXI.
                                REUNION.


When Roy Stone, having repaired the leak in his radiator, descended in a
long spiral, bringing his airplane to rest on the desert not far from
the mouth of the Great Road, he found as strange a reception committee
awaiting him as ever greeted an aviator's landing.

It was near the hour of sunset. The last rays of the descending sun,
balanced on the edge of the world and about to sink below the horizon,
shot almost straight across the desert. Low sand dunes of so little
height as to seem almost invisible at noon, now shot lengthy grotesque
shadows to the east. The face of the Great Mountain Wall, solid unbroken
gray rock, glowed in a misty golden light. The far peaks of the interior
country, rising from pools of purple shadow, seemed like lighted cones.
The shadows of those standing grouped on the desert floor and waving
hands and burnooses in greeting, wavered to extraordinary length to the
eastward along the desert floor.

In that group were the majority of the dozen revolutionists of the
Korakum guard, only four having been left to patrol the spot where the
river broke through the interior mountains to run swift and wide around
the valley of Korakum. Bare-legged, togaed, they alone made a
sufficiently strange effect. But added to their number were Ali and four
of the Arabs. Akmet having been left to aid the Korakum guards, and they
were dressed in their flowing burnooses while beneath their turbans
appeared swarthy faces, hook-nosed and bearded. To cap all, were Mr.
Hampton, Jack and Frank, who had discarded burnooses in favor of soft
tan shirts, khaki pants and sandals. They still wore their sun helmets.

Descending in a long spiral, the airplane--a four-passenger bomber
type--struck the sand lightly, skimmed lightly across a sand dune and
came to rest on a smooth hard floor of sand.

From it stepped first Roy Stone, tearing leather helmet and goggles from
him and exposing a tanned face beaming at the greetings of the boys who
were approaching at a tearing run, and then Amrath whom Stone assisted
to alight. At sight of the latter Horeb who followed the boys let out a
shout of joy, and the next moment the two revolutionists were clasped in
each other's arms, while their countrymen flocked about them, and from
the mass came a confused clatter of Athensian language for all the world
like an ignited pack of firecrackers.

"Listen to 'em hit their bloomin' language on the nose," ejaculated Roy
Stone, grinning. "Well, me lads," he added, pumping away vigorously, for
Jack and Frank each had seized a hand, "I'm tickled to death to see you,
but if you let go a paw for a minute I'd like to shake Mr. Hampton's
hand, too. If you don't mind, y' know."

Whereat the boys released his hands and proceeded to thump him
enthusiastically on the back, a procedure which Stone answered by
whirling quick as a cat, and with a stoop and a sudden twist catching
both by the legs and dumping them unceremoniously on the sand. A burst
of laughter came from the Arabs.

"Glory be that you arrived," said Mr. Hampton, as he clasped the
aviator's hand and looked deep into his steady gray eyes. "For one
thing," he added, in an undertone, "you've already done them good. What
they both need is a little play. They're breaking their hearts over
Bob's predicament, and that trick you just played on them has made them
laugh for the first time in many days."

Stone nodded understandingly and then, as the boys having risen to their
feet joined him, still laughing, he said in a calm matter-of-fact tone:

"No need to worry about Bob, any more. We'll snake him out of any old
mountain city in a matter of minutes. The old buss can go anywhere, and
if you lads and Uncle Roy can't turn a simple trick like that, why, by
golly, we ought to be sent back to school. How about it?" he concluded
challengingly.

"Right," said Jack, catching Stone's spirit of optimism.

"No question about it now," Frank firmly declared.

"That's the spirit," approved Stone. "Well, give me a couple of trusty
men to place on guard over the old buss so that nobody gets curious and
steals the engine or something, and then lead me to a bite to eat. I
could sink a tooth in some food without a qualm."

"We've thought of the matter of guards," said Mr. Hampton. "These
Athensian revolutionists and the Arabs all have seen airplanes before,
the Athensians having served in the various Spanish and French Foreign
Legions of Northern Africa or the British Sudanese forces. So none is
scared of it. Lieutenant Horeb has promised to put two men on guard, and
I think we can safely leave it to their charge. Yes, as you see"--he
added, pointing--"two men already have taken up their posts."

"All right, then, come on," said Stone nodding. "I've taken the keys,
and nobody can fly away with her. And out here on the desert, it's
hardly likely there will be visitors, so lead on. I'm a starving man."

Amrath approached to greet Mr. Hampton, whom he thanked again very
earnestly for having saved his life, and to be introduced to the boys.
His deep eyes glowed as he clasped the older man by the hand, and
promised his compatriots would spare no effort to rescue Bob from
Athensi. Then he departed with Horeb and the other revolutionists, while
the Hampton party with Roy Stone in the center, fell in behind, for the
walk up the Great Road to Korakum.

"Just the same," said Mr. Hampton, as Amrath passed beyond earshot, "I'm
banking more on your efforts to save Bob by means of the airplane,
Stone, than on those of the revolutionists. Their leader is proceeding
cautiously, so as to rally the whole country around him before he moves
up to attack the walls of Athensi. Unless he executes a coup, gains
possession of the city by a trick, it will take months to bring about
its fall. Of course, he may not be successful at that, as the Oligarchy
has a powerful trained army of 5,000. No, it's the airplane that must be
our salvation, or, rather, Bob's, for it is quite possible the
Sacrificial Games in Athensi may come and go before the rebels succeed."

Stone nodded.

"This fellow Amrath has been explaining the situation to me," he said,
"so I know what you're talking about. And I'm inclined to agree with
you. But I feel confident we can snake Bob out in the airplane. Amrath
has given me a minute description of the situation of Athensi and of the
location of the gladiators' training camp, so to speak. He's even drawn
me a kind of a rude map which I'll show you later. It'll be touch and
go, quite likely, but we'll do it all right. I've got an ace in the hole
which I'll tell you about later."

Mr. Hampton dropped a hand on the aviator's shoulder and pressed hard.

That night in Korakum there was a feast and merrymaking. Horeb had sent
word to Captain Amanassar of the expected arrival of their comrade
Amrath and of a friendly aviator with an airplane which he would place
at their service, after first attempting the rescue of the young
American captive from Athensi. This word he had sent as soon as learning
from Mr. Hampton of the message the boys had received by radio. Captain
Amanassar would not be able to come to Korakum, but Jepthah who
commanded at the entrance to the other pass, appeared as the feasting
began, and an affecting scene occurred on his reunion with Amrath.

Goats were killed, a skin of native wine was produced by the
revolutionists, there was a profusion of vegetables from their garden
plots, and the mingled Athensians and Arabs made merry, Mr. Hampton, the
two boys and Roy Stone, sitting at one side of the great fire, in the
light of which stood out not only the startling faces of Athensians and
Arabs but also the many-pillared front of an ancient temple at their
backs, looked on in delight at the scene. They were talking over plans
for the rescue of Bob, and examining the map of Athensi drawn by Amrath.
But even in the absorption of this pursuit, one or other would now and
again lift his eyes to gaze in artistic appreciation at the strange
sight.

Finally, even the map was put away, and the four turned all their
attention to their surroundings, for Akmet had been persuaded by his
fellows to tell a story and, once he began, although his language was
understood only by his fellows, the Athensians and the Americans alike
fell under the magic of his spell.

Many times before, at night encampments, Mr. Hampton and the boys had
heard Akmet recite stories. For, among Arabs, Moors, Berbers, and the
Negroes of the Sahara, the poet and the story-teller are held in high
esteem. And, although none of his American auditors could understand a
word of the Arabic, yet he had the gift of portraying by tone and
gesture the very spirit of the words.

At such times the three, with their sensitive imaginations, had been
stirred deeply. As for the Arabs, Akmet never failed to hold them
spellbound.

"You have a treat in store," Mr. Hampton whispered to Stone.

But tonight Akmet was not the story-teller, but the composer of verses.
From a fold of his burnoose he drew out a beautifully worked small lute
upon which he struck with an eagle quill. For a moment or two he
thrummed idly, without tune, seeking a chord that appealed to him. At
the same time he stared all around the group which had drawn closer
about him, looking through vacant eyes at each in turn. There was a
pause, during which Ali drew close to Mr. Hampton and whispered:

"He is a poet--sometimes a great one. You will see and hear."

Suddenly Akmet struck a new chord, one evidently to his liking. He
repeated it several times--a chord so deep and sad it sent a thrill of
emotion through every man there. Then he began to sing in a pleasing
barytone. At first he went slowly, awkwardly, but soon crowding thoughts
expressed themselves in words fluently and with grace. When he finished,
with a crash, there was not a dry eye.

Ali snuffled and leaned closer to Mr. Hampton.

"He was great that time," he whispered. "He sang of his home in the
Sous. That is Berber land, far to the west of us. He has not been home
in many years, and that was a song of home sickness."

"Great it was," returned Mr. Hampton, "but," he added, with a sidelong
glance at the solemn faces of his son and Frank, "tell him to give us
something more cheerful."

Ali nodded and made his way to the side of Akmet who sat expressionless
in the midst of the storm of enthusiastic applause from his countrymen
in which the Athensians joined generously. Stooping, he whispered some
words in Akmet's ear at which the latter nodded imperceptibly and cast a
swift reassuring glance toward Mr. Hampton before again dropping his
eyes.

Then Akmet's fingers struck the lute again. A new note clanged--a
warlike note, and Akmet began. There was no need for translator. The
Arabs knew what he said. They sat big-eyed, open-mouthed, scarcely
breathing, under the spell of the poet. Nobody else knew, but they did
not need to know. It was as clear to them as if they understood every
word. Clear, not alone from the emotions Akmet aroused within their own
breasts but also from the story written on the faces of the singer's
countrymen.

It was a tale of war. And the swarthy face of the singer, played upon by
the leaping flame, portrayed every mood. His audience could see the
warriors riding across the barren wastes of the Great Desert, could hear
the clash of scimeters, the crackle of rifle fire, the whirring flight
of arrows and, at length, the women wailing of death. When the climax
came, it left all tense and wrung dry of emotion. As for Akmet, his face
sunk into an expressionless mold, he put the lute away, and stared into
the fire, while the Athensians applauded wildly and the Arabs flung
themselves upon him as if merely to touch his robe would bring them
happiness.

Ali was lost in this wave of emotion like the rest. Presently he
extricated himself, and made his way to Mr. Hampton's side.

"That," he said, "was the finest story I ever heard. But I can't
translate it for you."

He turned abruptly and strode away.

"Whew," ejaculated Roy Stone. "The beggar is cocky."

"No," said Mr. Hampton, "just stirred profoundly. Well, so was I. The
Arabs, I have heard, are the greatest story tellers and poets in the
world. They never write their stories, but sing or recite them, and thus
they put into them infinitely more than the peoples who merely write."

"Well," commented Jack, "no story I ever read held me so enthralled as I
was tonight."

"And no play or movie I ever saw," added Frank. "I guess that must be
true about the Arabs if Akmet is a fair sample."

After some further desultory conversation, the four Americans retired
for the night. Two Athensians were sent to the desert to relieve the two
on guard over the airplane, and the little encampment amidst the ruins
of Korakum sank into slumber.




                             CHAPTER XXII.
                          FRANK TO THE RESCUE.


All the Americans arose early the next morning, for they were resolved,
if possible, that the day should see Bob's rescue carried out; at least,
should see it begun.

Nothing untoward had occurred during the night; the guards at the river
reported no danger from the direction of Athensi, and those in charge of
the airplane, when relieved by two Arabs whom Stone and the boys
accompanied, reported the night had been uneventful. Leaving the two
Arabs in charge, the three young Americans returned to the grove, where
their own camp was maintained, and found Mr. Hampton and Ali had
breakfast ready, consisting of coffee, bacon and flapjacks. All ate with
relish, and then turned their attention to plans for the day.

It had been decided that, if in the gladiators' quarters at Athensi Bob
had managed to set up his radio receiving apparatus, he would already be
aware of plans under way for his rescue, for he would have been able to
listen in on the conversation between Stone and the camp the day before.
Nevertheless, Frank broadcasted a message, telling Bob to look for them
that day, in the hope that it would reach him, and adding that he would
call later to give him definite details. Then he rejoined the group,
poring over the map of Athensi drawn by Amrath.

The latter, accompanied by Jepthah and Horeb put in an appearance while
the Americans were bent over the map, and a lengthy discussion of ways
and means followed.

Athensi lay in a high interior valley. On one side it was built right up
to the edge of a steep precipitous bluff at the foot of which flowed the
river, which, rising in the mountains behind, flowed through a series of
natural tunnels through intervening mountains until, emerging in the
valley of Korakum, it disappeared under the Great Mountain Wall to
reappear none knew where.

On this side there was no need for walls, as the bluff itself could be
scaled only by means of a series of ramps constructed in zigzag fashion,
with towers at every turn. On the other three sides it was enclosed by
high stone walls, which the revolutionists said were kept in a good
state of preservation.

In the middle of the city, a crowded mass of poor huts and houses
sheltering fifty thousand people reduced by the Oligarchy to a state of
serfdom, was a great open space, two-thirds of which was occupied by the
citadel, the library, the temple, a pyramid on top of which stood an
altar where the sacrifices were held, and the half dozen great palaces
of the court, all surrounded by a wall. The remaining third of this
great space, outside the wall, was taken up by the Coliseum. It was of
stone, oval in shape, and in it were held the annual Sacrificial Games.

"Under those tiers of seats are the gladiators' quarters," explained
Amrath, dabbing at the map with a forefinger.

"Then to get Bob, we've got to alight in the Coliseum?" asked Jack,
drawing in a long breath as he realized the difficulties. "Whew."

Mr. Hampton's face was grave. Should he give his consent to such a
procedure? Would it not be merely to throw away the lives of whoever
made the attempt without effecting the rescue of Bob? It began to appear
so.

"Amrath explained all this to me at the oasis," said Stone. He sat back,
quietly regarding Mr. Hampton. "But I've got a trick up my sleeve," he
added, "which puts a different complexion on the matter. I didn't speak
of this last night because there was no need or opportunity. But now let
me explain.

"Amrath tells me," he went on, "that the gladiators destined to
participate in the games are taken out into the arena every morning and
every afternoon for exercise. In the morning, the young Athensians who
are to be paired with the outside gladiators are exercised. In the
afternoon, the others."

"Yes, that is so," said Jepthah, and Horeb, who also spoke English,
nodded.

"On a tower or platform in the middle of the arena a group of a dozen
Janissaries mount guard," continued Stone, looking to the young
Athensians who confirmed him with nods. "If the gladiators should plan a
concerted revolt and attack the Janissaries, they would be out of luck.
Without firearms, they would be shot down by the Janissaries without a
chance.

"Now," he continued, "if I had no means of combatting the Janissaries,
of putting them out of commission, in fact, I'd be out of luck, too. The
minute I landed in the arena, they'd open fire. But--" He paused and
glanced about at the tense faces of his audience, every man of which
hung on his words. "But," he continued, "what would you say to dropping
gas bombs on them?"

This was the "trick or two up his sleeve," of which he had spoken. Its
effect was magical.

"Have you any such?" demanded Frank, excitedly.

"A half dozen of 'em," said Stone, complacently. "Enough to put the
Janissaries to sleep with lots left over. I'll drop a gas bomb on their
platform, and if I miss I'll drop another. I can fly low above them,
because I'll have nothing to fear except their rifle fire, and the old
buss is sheathed to protect it against that. So there will be no reason
to miss."

"But where did you get these gas bombs?" asked Mr. Hampton, recovering
from his surprise, and beginning to show the relief he experienced as
the possibility of effecting Bob's rescue again grew bright.

"Hooked 'em from the Spaniards," said Stone, unashamedly. "I had a
run-in with my commander over the justice of his cause, and as I had to
leave without my pay, I took along the bombs and an extra supply of gas
to compensate. Loaded the drums of gas in the old buss. The plane's
mine, you know. Bought it in France at an auction of surplus war
supplies, but that's another story."

The eyes of Jack and Frank sparkled.

"Come on, let's go," shouted the latter, leaping to his feet.

"Hurray," yelled Jack. "We're on our way."

"Wait a minute, wait a minute," said Roy Stone. "It's only a sixty-mile
flight to Athensi, and we'll be there in less than an hour. We have got
to wait, and to time our departure so as to arrive at the hour of
exercise this afternoon. Even then our friends here"--indicating the
young Athensians--"may have guessed wrong as to the time of exercising
the alien gladiators, and then we'd be up the spout."

Jepthah shook his head in negation.

"Procedure in Athensi never changes," he said. "Two hours after midday
the alien gladiators are taken into the arena for exercise and training.
It has always been so."

"Good," said Stone, "then we start at half past one to the dot. Now to
settle who goes. One of you boys will have to go to fly the plane. I'm
the only one who can drop the gas bombs, so that lets me out of the
flying. And one of the Athensians will have to go as guide. Amrath wants
the job, and, as I can _parlez vous francais_ and so can understand him,
that's all right. Now which of you two fellows takes the stick?"

"Frank," said Jack instantly.

He himself was dying to undertake the flight, but he knew the depth of
affection between his two comrades, and not for worlds would he have
deprived Frank of the chance to rescue Bob. Frank, who had remained
silent, regarded his chum gratefully and reaching out squeezed his hand
hard.

"All right," said Stone. "Frank it is. We can take only three, because
we need the fourth seat for Bob coming back. And now," he added, rising,
"let's go down to the old buss and tune her up, give her a good
overhauling, and run her around a little with you at the stick, Frank,
so you learn her tricks."




                             CHAPTER XXIII.
                        THE FLIERS WARN KORAKUM.


After a hectic morning, all was ready for the take-off as one-thirty
o'clock approached. Right up to the last minute, Frank was kept by Stone
at practising landing and taking-off within a limited space for,
although the description given by the young revolutionists of the
tremendous size of the arena promised sufficient space for the delicate
work of alighting and re-ascending, yet Frank must be perfect.
Otherwise, if the plane smashed, the expedition would be wrecked. Once
inside of Athensi and the Coliseum, the only way to escape would be by
means of the plane.

Understanding full well the responsibility resting upon him, Frank
concentrated on the task in hand. An expert aviator with four years of
flying to his credit, he won the approval of Roy Stone as he managed the
plane in masterly fashion and as his landings and ascents approached
perfection. Finally, when twice in succession he had landed and
re-ascended within an oval traced on the desert sand which all the
Athensians, who could not recall the exact measurements of the arena,
declared according to the best of their recollection was even smaller
than that of the Coliseum, Stone ordered him to cease his efforts and
rest for an hour.

At the end of that period, sharp at one-thirty, the take-off was made.

What a cheering and hullabaloo there was as, with Frank at the stick,
and Stone and Amrath riding as passengers, the start of the flight was
made. Brilliant sunlight flooded the desert and, gathered in a group a
bit out from the Great Mountain Wall, revolutionists, Arabs and Jack and
Mr. Hampton waved farewells and called Godspeeds to the expedition.

Amrath occupied the seat beside Frank, for his was the task of piloting
the flight. Stone, sitting in the rear pit from which had been removed
the drums of gasoline which formed his surplus fuel supply, in order to
make room for Bob on the return trip, had his gas bombs nicely adjusted.
A grim smile crossed his features as he regarded them. Let one of those
bombs light on the stone platform of the Janissaries in the middle of
the arena, and those gentlemen would give no trouble to anybody for
quite some time.

Jack and Frank had clasped hands just before the latter clambered to his
seat, and the look in his eyes told better than words could have done
the gratitude he felt because his chum had stepped aside unselfishly and
given him the opportunity to fly the plane.

A running start out over the desert, away from the Great Mountain Wall,
a spurning of the sand, a turn in the air, and then higher and higher
mounted Frank seeking altitude. Those watching from the sands saw the
plane grow smaller and smaller until it seemed to their sun-dazzled eyes
only a mote dancing in the sun. Then away toward the Great Mountain Wall
headed Frank, crossed its serrated summit and disappeared.

Mr. Hampton's eyes were moist and his lips moved soundlessly in a prayer
from the heart for the success of the expedition and the safe return of
all concerned.

Jack's eyes were unashamedly moist, too, and, as they trudged back apart
from the others, Mr. Hampton's arm went across his son's shoulders and
stayed there. The two were very close in that hour.

A guard of six, four Athensian revolutionists and two Arabs, had been
left in the valley of Korakum to watch the river approach. Accordingly,
it was deemed unnecessary for the balance of the party which had
witnessed the start of the flight, to return at once and, instead, a
halt was made under the trees of the grove where the radio station had
been set up.

Jack took his seat at the instruments, while the others crowded around,
eager to hear the first word received from the plane with which, of
course, constant communication could be maintained. Earlier, before
going down to the desert after his rest period to begin the flight,
Frank had broadcasted a message of cheer to Bob, in the faint hope that
he might be able to receive it, telling him of the effort to be made
that afternoon for his rescue.

At once Jack began calling, and back came Stone's voice in re-assuring
accents almost immediately, telling that they had cleared the Mountain
Wall in handsome style, that the plane was performing flawlessly, and
that even the cross-currents of wind which tugged at them, sweeping down
valleys and canyons and around mountain peaks, seemed to make no
difference to Frank. To the latter's skill, Stone paid handsome tribute.

All this Jack repeated to his auditors and Ali and Jepthah interpreted
for the Arabs and the revolutionists respectively. Jepthah had stayed to
witness the start of the expedition instead of rejoining his command and
now intended to wait the few hours more which would tell its outcome.

Suddenly, excitement seized Jack. His brow contracted, his eyes blazed.

"Say that again," he shouted into the transmitter.

A moment of concentrated listening, then:

"All right, I'll tell them. How far away, did you say? Twenty-five miles
of straight flying. All right, all right. We'll be ready for them."

Tearing off the headset in his eagerness, he whirled around to the crowd
which, alarmed by his tone even though the words were not understood by
most, had drawn close about him. His eyes sought and found Jepthah and
him he addressed:

"There's an attack against Korakum coming by way of the river. As the
airplane crossed a gorge twenty-five miles from here through which the
subterranean river ran exposed, Amrath counted three boatloads of armed
men making their way toward Korakum. There may be more. He didn't see
them. About twelve men in a boat."

"Perhaps, they are not advancing on Korakum," suggested Mr. Hampton.

Jepthah shook his head in negation.

"They could be going nowhere else," he said. "Well, thanks to our
friends, we are warned. We shall be ready for them."

Turning, he issued a crisp order in Athensian which caused the
revolutionists in the group to dart away at once. Their bare legs
flashed as they raced through the grove, then they leaped over the
underbrush at the edge of the terrace without even seeking out the path
which had been cut through it, and started running up the Great Road.

"Your Arabs," said Jepthah, tersely, to Mr. Hampton, "can we count on
them?"

"They are free agents," said the latter. "I'll ask Ali."

The latter, standing close at hand, did not wait to be appealed to.

"We are at your command, sir," he said to Jepthah.

Between this educated Arab with his cosmopolitan experience and air of
mystery, and all the young Athensian revolutionists, had developed a
warm feeling of mutual liking and respect.

"I knew it," said Jepthah. "Good. Would you take your men and report at
once to Lieutenant Horeb."

The latter had not gone down the Great Road to witness the start of the
flight, but had remained in command of the tunnel guard.

Ali gave a quick nod, more eloquent than words, said something in Arabic
to his four companions, whose eyes gleamed with satisfaction at the
prospect of a fight, and without more ado the five set out in pursuit of
the revolutionists.

Only Jack, Mr. Hampton and Jepthah were left in the little grove. Even
the camels were missing, having been taken to the valley of Korakum to
graze. Hardly had the last Arab disappeared up the Great Road than the
clatter of hoofs was heard approaching, and a man on horseback dashed by
making for the desert at a break-neck pace.

"Twenty-five miles away," explained Jepthah. "The river flows swiftly,
and they will row besides. Yet they cannot reach Korakum for an hour or
more. I ordered one of the men to ride to the other pass and bring help.
Thirty-six men will outnumber us two to one, and it is more than likely
there will be many more."

"Can help arrive from the other pass in time?" asked Mr. Hampton,
anxiously.

"Not before the attack begins," answered Jepthah. "But we will have the
advantage, and can hold the enemy off, for a time."

The defenders of Korakum had thrown up earth works at each bank of the
river, where it broke from the interior mountain range into the valley.
Besides, for a considerable distance along the river, inside the tunnel,
they had dumped heaps of big rocks which rose close to the surface and
against which, in the gloom, carried along by the swift current, boats
approaching from Athensi would be smashed. Where the river emerged into
the open, strong nets had been spread under the surface, staked down to
the banks, and sharp stakes also had been driven into the river bottom.

The result was that boats approaching from Athensi would have a perilous
gauntlet to run. Smashed against the rocks inside the tunnel, their
occupants would be carried along into the nets and, if they managed to
get through these, they would be involved in the sharpened sunken stakes
below. All the time, rifle fire would be playing on them from the
earthworks, and showers of arrows would be whirring into their midst.

Determined men, of course, could effect a landing, but only at a
tremendous loss of life. It was said of the Athensian Janissaries,
however, that they were absolutely fearless. Their ranks were recruited
from the sturdiest, strongest sons of the peasants, seized from their
homes before old enough to have imbibed the popular hatred of the
Oligarchs and trained in the practise of arms at Athensi. They never saw
their relatives again and became mere creatures of the Oligarchy.
Knowing they were hated and despised by the people as traitors to their
blood, and that if captured they would be slain without mercy, they
fought with unparalleled ferocity when employed to quell the numerous
rebellions.




                             CHAPTER XXIV.
                           INTO THE COLISEUM.


"We're approaching Athensi. Boy, what a place. We can see the arena.
We're over it and Frank is dropping the old buss. Now he's pancaking,
and they're beginning to shoot at us from the platform, and the--Well,
say, I'll talk to you later."

Roy Stone's voice ended abruptly. Jack turned to his father, who was
pacing up and down the grove, listening for word from Jack, listening
too for sounds from Korakum which would indicate the arrival of the
Janissaries and the beginning of the attack, torn between conflicting
emotions, eager to hear of the outcome of the attempt to rescue Bob, and
desirous also of doing his part to beat off the Janissaries, and called
to his anxious parent the purport of Stone's last message.

The two looked at each other. At that moment, the sound of rifle fire
came to them from the direction of Korakum. Mr. Hampton seized his rifle
and started up the Great Road.

"Take care of yourself, Dad."

Jack was to stay and hear the outcome of the daring attempt to rescue
Bob. He felt a strange tightness of the throat as his father
disappeared. Would he ever see him again? Would he ever see Bob and
Frank again? What was to be the outcome of it all?

                            * * * * * * * *

Less than an hour from the time of taking-off, Frank nosed the airplane
through a gorge between towering mountains the sides of which were
cultivated in terraces half-way to the summits. Men, women and children,
at work in the fields, stood paralyzed with terror, unable to move, this
strange monster of the air zoomed along. But those in the plane paid
them no attention.

They were watching a point ahead, where the two sides of the gorge drew
closer together until they were less than a quarter-mile apart. Beyond
they glimpsed a great open plain, in the distance, beside a pencilled
cleft, the walls of a city at the heart of which rose a clump of great
buildings. Only a glimpse they caught, and then the converging walls of
the gorge shut out the sight.

Steady as a rock, seemingly without a nerve in his body, Frank whipped
the plane between the narrowest point of the mountain walls and found
that the valley opened out abruptly at once. In a minute or two, as they
zoomed along, the mountains had retreated miles away on either hand,
they were flying over an intensely cultivated plain, the river flowing
below in a gorge that cut through the heart of the plain, and the walls
of the city seeming to leap into gigantic size ahead.

No longer did Frank require directions from Amrath as to how to proceed.
Everything lay clear below--the city walls, the crowding hovels within,
and in the middle the walled inner city of the Oligarchy with the
Coliseum at its gates. Over the Coliseum he passed, began to spiral, and
then pancaked. It was then Roy Stone called his last message to Jack, as
with gas bomb ready, he prepared to do his part.

Against the metal bottom of the plane came the tiny ping of a rifle
bullet or two, but for the most part the shots of the Janissaries on the
tower went wild. The ground seemed rushing up to meet them. Throughout
the vast oval, surrounded by its banked tiers of empty stone seats,
little groups and pairs of men paused in their movements as if stricken,
turned into stone, at the sight of this strange monster overhead.

Only, from one group, a figure darted away, running along the
hard-packed sand of the oval, eyes uplifted, arms waving wildly. As
Frank glanced down, his eyes as if drawn by the force of that ant-like
figure's gaze, singled it out of all below. In his heart he knew it was
Bob, and that, whether he had received their radioed messages or not,
Bob realized friends were at hand.

Then below him there was a crash, followed by another, and he knew Roy
Stone had landed his gas bombs on the stone platform of the Janissaries,
in the very center of the arena. Had they fallen into the sand, no such
sound would have followed.

He could not delay to gauge the effects of the gas bombs. He must take
it for granted they had put the guards out of business, and proceed to
land. Even if any Janissaries were left to shoot at them, the chance
must be taken. The airplane could not hover longer without being brought
into descent, or it would crash. Further, they must operate swiftly, or
the gas wave would sweep over the arena and put them out of business,
too. Against this contingency, Frank was guarded, but not the others.
Roy Stone had one gas mask, but only one, and Frank had been provided
with it, as upon him as flier depended the ultimate safety of all.

For one thing he was grateful. The Athensian revolutionists, if
anything, had underestimated the vast extent of the Coliseum. The arena
oval alone was longer than a city block, and between the stone platform
of the guards and the sides was room for three planes.

Down swept the plane and Frank, even though his eyes were glued to the
course, out of the tail of them saw a thin vapor mushrooming above the
guard's platform which he knew must be the released cloud of gas. Not a
shot came from the platform as they swooped past. Ahead, the gladiators
had run from the path of the oncoming plane to throw themselves prone at
the base of the surrounding wall.

All except one. He--a strange figure cumbered in heavy armor, of
breastplate, and greaves on thighs and calves--was running parallel to
them and waving. Evidently, too, he was shouting, but even though the
motor was shut off his words could not be heard. There was no doubt,
however, of his identity. He had torn off and cast aside a helmet with
overhanging crest, and his yellow hair was bare and gleaming in the sun.

It was Bob.

The wheels of the plane touched the oval, but likewise the end wall
seemed rushing to meet the charge. Frank set his teeth, worked the tail,
and the big machine swung gracefully in a circle, the outer wing not a
foot from the stone wall above which rose the tiers of seats, and came
to rest.

From the middle where he had thrown himself flat on the sand while Frank
executed his maneuvre, Bob regaining his feet sprang for the plane.

"In with you, quick," cried Stone, lending a hand, and Bob
half-clambered, half was dragged into the rear pit.

Frank pressed the starter, and the engine, still on compression, resumed
operations with a roar.

"Hold your noses," yelled Roy Stone, "I smell the gas."

Sweetish acrid fumes, in fact, were in their nostrils. Frank set the
plane in motion down the arena, himself immune because of his mask,
while the others sat with noses pinched between thumb and forefinger and
eyes screwed shut. Down the sand tore the plane and when near the
platform in the center it began to lift. Up, up, it went, yet not as
swiftly as Frank could have wished. As the far end of the Coliseum was
approached, he experienced a sick panic that they would not be able to
rise fast enough to clear the banked-up seats.

Banking as steeply as possible, he began to swing obliquely, and this
maneuvre, dangerous to equilibrium, though it was at such a low
altitude, and before speed had been picked up, had the desired effect.
The widening arc of the Coliseum gave him just enough room for
operations so that as he drew near the side he was able to drag the
plane over the top tier of seats.

Yet how little room there was to spare was brought home to all with
ominous significance, for, as they cleared the top of the lofty stone
seats, there came a shock, and a quiver shook the plane which caused
Frank to struggle desperately. The next moment they were free and
mounting rapidly and the danger was passed.

"We bumped with our wheels," cried Stone. "Don't see 'em behind us, so I
guess they weren't torn off, but you'll have a sweet time landing."

A little nod of the head was all Frank's reply. What cared he about a
messy landing? He could manage not to hurt anybody seriously. And any
damage to the plane would be more than compensated for by Mr. Hampton.
The big thing was that Bob was safe, safe; that he, Frank, had been able
to fly a plane in and out of the Coliseum and rescue his big chum.

A hand closing hard on his shoulder from the rear sent a thrill
throughout his body, and a bellowing voice shouted:

"Got your message, old kid. Knew you could do it."

That was all, but that was enough. No matter what praise others might
bestow, Frank cared naught.

High over Athensi he circled, seeking his bearing for the mountain pass,
before darting away, true as a bird. And from their lofty altitude, the
others looked down. Now that it was all over, the experience seemed like
a dream. In the minds of both Amrath and Roy Stone, still lingered
thankfulness for their amazing escape from disaster and wonder at it,
too, yet exultation over the success of the daring attempt rapidly
replaced all other thoughts.

As for Bob, it would be hard to describe the chaos of his thoughts. He
had never quite despaired of being saved by his friends, yet when once
his captors had reached and entered their mountain country he had
realized that nothing less than a miracle could save him. Practising at
arms day after day with trainers, cooped at other times in the
gladiators' quarters deep beneath the great stone pile of the Coliseum,
he had seen no possible way of escaping. Heart and brain had turned sick
at the thought of giving up his life to make holiday for semi-savages.

One of his trainers he had bribed with the gift of his gold watch to
bring him the coils of wire and the collapsible standards for setting up
the antenna. This same trainer had erected the antenna amid the tiers of
empty seats, which would not be occupied until the Sacrificial Games and
so, finally, Bob had managed to get his little radio set to working.

Only very faintly had he heard the messages sent out by the boys from
Korakum, and numbers of the words could not be heard, try as he might to
tune up. The trainer, receiving his bribe, had shown no further interest
in the radio, the use of which was altogether unknown to him. As for the
other prisoners, Negroes of various tribes, they were either sunk in
apathy and paid Bob no attention, or else out of some vague notion of
respect for the white man kept their distance.

Thus Bob was not spied upon nor reported. And, faint though the words he
did hear, yet he understood enough to realize an effort to rescue him by
airplane was to be made that afternoon.

How he had seized the opportunity is known.




                              CHAPTER XXV.
                    A SURPRISE FOR THE JANISSARIES.


As, flying over the rugged mountain country, they whirled back toward
Korakum, Roy Stone bethought him of Jack. Thereupon he opened
communication, and Bob himself announced to his other chum the tale of
his own rescue.

From Jack the party in the plane learned that the attack on Korakum via
the subterranean river had begun fifteen minutes before, and was
proceeding fiercely so far as Jack could tell from the distant sounds of
rifle fire. His anxiety regarding the fate of his father and of the
small band of Athensian rebels and Arabs communicated itself to them.

Instead of flying straight out to the desert and landing, it was decided
to follow a route which would bring them over the scene of conflict, if
for no other reason than to learn how affairs progressed. Should the
revolutionists be forced to flee, it would not be safe for the airplane
to land on the desert near the Great Road, inasmuch as, with damaged
wheels, it would not be able to re-ascend and would be captured, even if
they escaped.

Besides, as Roy Stone pointed out, there was the bare possibility that
they might be able to render help. Four gas bombs remained. If the
Janissaries had managed to effect a landing and were in considerable
force, dropping of the gas bombs amongst them would wreak havoc.

Accordingly, under Amrath's guidance, Frank altered his course and
presently, after scaling the mountain range blocking the upper end of
Korakum valley, dropped down spiralling above the plain.

Amrath had glasses to his eyes and was studying the scene below.
Evidently, the fight had gone against the revolutionists. No longer did
they hold the earth works at the tunnel mouth, although heaps of bodies
entangled among the stakes in the river and lying thick along the river
bank and up to the top of the ramparts showed they had wreaked deadly
execution before retiring.

Retiring now they were, however, but in good order. The horses of the
revolutionists and the camels of Mr. Hampton and his party had been
brought up in readiness for a quick retreat, and mounted upon them the
defenders were fleeing down the valley, well in advance of the
Janissaries. The latter, afoot, were rapidly being outdistanced.

That there had been losses amongst the defenders was only too sadly
apparent. Of the gallant little band of eighteen, ten Athensians and Mr.
Hampton, Ali and their six Arabs, only a dozen were left. But Amrath's
glasses showed him bundles being borne away with them by the living, and
he knew them for the bodies of those who either had been wounded or
slain. Perhaps, they had only been wounded.

Where the walls of the pass through which ran the Great Road out from
ancient Korakum to the desert drew close together, the revolutionists,
anticipating the necessity for falling back in case of attack, had
thrown up a strong barricade across the pass from wall to wall. For this
they were making and even as he watched, Amrath saw them pass in single
file through a breach left for that purpose. He knew that they would
drop into place a sheath of timbers and prepare for a final stand.

Rapidly the result of his observations were communicated to his
companions, and Roy Stone radioed them to Jack. The latter was wild with
anxiety for his father, and announced he would take his rifle and go to
the barricade to offer his assistance. He explained a messenger had left
for the other pass on receipt of the warning from the airplane of
impending attack, but that so far help had not arrived.

"Tell the fellows at the barricade to keep up their courage," was
Stone's last message to Jack, before the latter abandoned the radio
station. "Tell them to watch. I'm going to drop our gas bombs among the
Janissaries. They're marching bunched up and we ought to put a lot of
them to sleep. Although we saw only three boatloads on their way here,
there must have been a lot more, because there's a thousand at least on
the march below us. Well, here goes."

Jack did not stay to hear Roy Stone's closing words, however, for at the
report of the danger to the revolutionists he was off to see about his
father, and Roy spoke to the empty air.

Frank swooped low above the close-packed mass of the Janissaries,
streaming down the Great Road. High in the air he shut off his engine,
and not many had warning of his approach. Even those who did merely
gaped at the strange and terrifying sight instead of scattering.

Straight down the line of the Great Road flew Frank, and in succession
Roy Stone released and dropped the gas bombs. Into the crowded ranks
they fell. Not one missed the road. And, as they struck, the clouds of
vapor were released.

The airplane passed on and Frank, switching on the engine, mounted and
then turned to go back over their course and observe what effect their
bombs had caused.

Deadly, indeed, the execution wrought. Where a few minutes before the
Great Road had been alive with marching men, now it was a chaos of
writhing forms strangling in the powerful fumes. Many already lay still.
Ahead and behind the main body, others fled, stumbling, falling, rising,
dashing on, to get away from the unseen enemy that had laid their
comrades low. To either side fled still others.

Although Roy Stone had assured him in advance that the gas was not fatal
in its effects, the spectacle caused Frank to experience a sickish
feeling. How terrible it was, he thought, that men should thus be struck
down in masses. Even the fact that the Janissaries were atrociously
brutal, and richly deserved the worst of fates, was no comfort.

Abruptly, he turned and started to mount into the air, heading for the
desert. As they passed high above the barricade, Amrath through his
glasses could see the defenders busied closing the breach and preparing
for a last desperate stand. Not yet were they aware of what had occurred
in the valley, for the scene was hidden from them. A little figure,
speeding up the Great Road, was seen and was presumed to be that of
Jack. Well, he would let the defenders know in a moment that the
airplane had done its part, and that an attack in force from the
Janissaries need not be looked for, at least not for some time to come.

Now for a landing. Emerging from the pass, Frank mounted high and then,
with engine shut off, began to descend on a long gradual slide,
intending to pancake at the end and to drop as lightly as possible. With
the wheels torn loose, as they suspected, any other method of alighting
would be impossible. They would be shaken up, but would have to brace
themselves for the shock and take things as easily as possible.

While they were still in the air, they saw in the distance dashing along
the base of the Great Mountain Wall, a score of mounted revolutionists,
followed by a considerable number afoot, and knew that aid for the
defenders of the barricade was on the way. Well, thanks to Roy Stone's
gas bombs, the effects of which had incapacitated a large portion of the
Janissaries, the re-inforcements would be in time.

In fact, sweeping into the valley of Korakum, they would be able to turn
the tables on the enemy. These thoughts rushed through the minds of all,
as Amrath communicated the meaning of the tiny figures which, as he
alone carried glasses, were plainest to him.

Then came the pancake, and the final drop. But in the end the plane
received little damage nor were its occupants much thrown about. The
carriage holding the wheels, torn loose in front when the wheels scraped
the upper edge of the Coliseum's tiers of seats, was still firmly
fastened at the rear. Thus, the wheels hung slantwise. Had Frank,
ignorant of what had occurred, attempted the usual landing, the results
would have been disastrous. But by pancaking and dropping, the wheels
were pushed up against the bottom of the plane and held firmly in place,
instead of being torn entirely from the fastenings.

The result was that the plane, although racketted about a bit, suffered
no more than in a bumpy landing, and came to rest without burying nose
or wings in the sand as had been feared would be the case.

All climbed stiffly out, and the next minute Frank and Bob were hugging
each other like a couple of kids, and thumping each other on the back
with terrific whacks. In the meantime, Roy Stone and Amrath stood aside,
and it was not until Frank and he had pummelled each other to their
mutual satisfaction that Bob turned to the aviator.

"Haven't had much chance for personal conversation with you up there in
the plane, Stone," he said, as he wrung the other's hand. "But I want to
tell you--Oh, shucks, what's the use? I can't sling language much. Only,
I will say I never got more benefit out of a fight in my life than out
of that one with you in the cave back in Old Mexico."

Roy Stone grinned through the sun-wrinkles about his eyes. He knew Bob's
reference was to the affray between the two parties in the lonely
mountains of Old Sonora, when the boys were striving to rescue Mr.
Hampton from the hands of the Mexican rebels. At that time, as recorded
in "The Radio Boys on the Mexican Border," Stone had been in the rebel
forces. But later he changed his allegiance, and warm, indeed, had been
the friendship between him and the boys, particularly between him and
Bob, who had been his own individual opponent in the fight in the cave.

"You like fighting so much," said Stone, "that it's a wonder you
consented to let us take you away from the Coliseum back there in
Athensi."

Bob shook his head and threw up his hands.

"A fellow can get too much of any good thing," he said. "Well, let's
snap into it and go back to this place where our friends are fighting.
Maybe we can help a little. But first I'm going to leave this hardware
here."

Whereupon he stripped off the various pieces of heavy armor and tossed
them into the pit of the airplane, standing revealed in nothing but a G
string--a superb figure who caused Amrath, for one, to draw in a breath
of admiration.

"Monsieur would have been a hard man to beat in the Sacrificial Games,"
he said in French.

"Aw, forget it," said Bob. "Come on. Got to give Jack and Mr. Hampton a
hand."




                             CHAPTER XXVI.
                      THE REVOLUTIONISTS SUCCEED.


In advance of the mounted re-inforcements from the other pass, which
still were some distance in the rear, the four adventurers entered the
Great Road and started at a trot up the gradual ascent, Bob in the lead.

"Don't hear any firing yet, do you?" he shouted over his shoulder to the
others. "You fellows have got revolvers, but I'm going to hop ahead and
root for one in the luggage."

Frank had explained about the grove where their own party was encamped
and where the radio had been set up. It was here Bob intended to look
for his automatic, which he had not taken with him when departing from
the distant oasis on that memorable ostrich hunt.

"Not much use this, unless at close quarters," he called, waving a
short, heavy sword of hard wood--a dummy weapon which he had been using
against a trainer when rescued from the Coliseum. "Might brain a man
with it, but that's all."

With a farewell wave of the wooden sword, Bob's naked figure drew away
from the others. It was late afternoon, and the Great Road already lay
in the shadow cast by the western wall of the pass. Hot though it was,
the relief from the heat of the desert was instantaneous, and the others
felt it at once and began to increase their speed.

As they passed abreast of the grove, Bob emerged, flourishing his
automatic, the dummy sword left behind. As he fell in beside them he
cried with a grin:

"Well, I'm all dressed up now."

Despite their labored breathing, the others could not restrain a laugh
at the ridiculous idea of a naked man considering himself dressed with a
revolver.

After all, their services were not needed. When they arrived at the
barricade, they found the defenders still awaiting the attack which had
failed to materialize. Jack's earlier arrival with Roy Stone's message
that he intended to drop gas bombs in the midst of the Janissaries had
given them the solution of the mystery, and the explanation of the
fliers regarding the damage wrought was greeted with delight.

The little band had suffered slightly by comparison with the terrible
execution they had worked among the Janissaries at the tunnel exit of
the subterranean river. Yet their losses had been severe enough.
Lieutenant Horeb and one of his men had been killed; Akmet, two other
Arabs, and three revolutionists had suffered dangerous, though not
fatal, injuries, and not one had escaped without some slight wound.

To the boys the fact that Mr. Hampton, praised by all for covering the
retreat with his repeater, had come through safely with no more than a
flesh wound in the calf of his right leg, was a matter for the greatest
thankfulness. As the three of them foregathered with Mr. Hampton and Roy
Stone, a little to one side of the main group, the thought occurred to
all that they had reason, indeed, for gratitude at having passed
practically unscathed through their numerous and deadly perils.

Mr. Hampton, who was not given to outward religious manifestations, said
simply:

"Almighty Providence has looked after us all, fellows, and we mustn't
forget to give thanks."

And for a moment, each bowed his head and voiced the thankfulness in his
heart in his own way.

A clatter of approaching hoofs rang in the road, and up dashed the score
of hard-riding horsemen from the other pass, for whom Jepthah had
despatched the messenger.

A condensed account of events was given their leader, a lean hard-bitten
man older than the majority of the young revolutionists whom, the boys
later learned was Maspah, a nobleman whose gorge had risen at the
terrible punishment meted out by the Oligarchy to those earlier exiles
who had shown kindness to Professor Souchard and aided his return to
civilization, and who forthwith had fled to join the little outlaw bands
which finally concentrated at Korakum under Captain Amanassar and
launched the revolution.

His eyes gleamed when he was told of the demoralization wrought among
the Janissaries by the dropping of the gas bombs. While waiting the
arrival of the footmen, peasants armed with bows and arrows and
numbering 200, he had the breach re-opened to admit the passage of his
horsemen.

In the meantime, too, scouts were sent ahead with glasses furnished by
Amrath and Mr. Hampton, who had worn his in a case slung over his
shoulder, to mount into the tops of a grove of date palms just beyond
the mouth of the pass and inspect the valley. They returned presently
with word that in the distance, where the gas bombs had fallen, the
Great Road was still littered with men, but that to the left of this
spot, in the cleared space in front of the ruins of the ancient temple,
where the revolutionists had been accustomed to hold their meetings,
officers were re-assembling the scattered Janissaries not struck down by
the gas. A considerable number, perhaps four or five hundred, were
collecting.

Lieutenant Maspah looked thoughtful.

"They will be better armed than we," he said. "Yet we have thirty
horsemen, which gives us a big advantage and if we strike at once we
shall have the advantage of surprise, while if we delay they will
recover from their demoralization. Ah, here come the footmen," he added.
"I shall attack at once."

Only four of the camels of the Hampton party had been brought in, the
others having lumbered away to their grazing grounds in a distant
portion of the valley when their masters had been wounded. Akmet and his
two companions had been carried to the barricade on the camels of their
comrades. But from mounting these four camels, Ali and his remaining
Arabs could not be dissuaded. Their blood was up and they wanted a hand
in the last phase of the battle.

This left no mounts for the boys and Roy Stone, which caused Bob, who
wanted to "take a crack" at the bloody rascals, as he expressed it, to
grumble exceedingly. Mr. Hampton, however, was pleased that it should be
so, as he felt the lives of all had been risked sufficiently. Besides,
he had undertaken to look after the wounded, who as yet lay on the
roadside in the shadow of the western wall, and he needed aid to
transport them to the shade of their own camp in the grove where, with
medical instruments and drugs, he could make shift to probe wounds,
extract bullets, bandage and do his best to ease pain.

"The four of you," he said to his son and Frank, Bob and Roy, "can do
vastly more good helping me than out there in Korakum. We need litters
to move these fellows to the grove, so hurry back, cut down some of
those young trees coming up in the brush, and then return. Make your
best speed, too. I'll go along and get out my supplies and have
everything ready to do what I can when you bring me the wounded."

An hour later, word arrived by messenger sent back by Amrath, who knew
Mr. Hampton would be anxious to hear the result of the battle, that the
Janissaries had put up only a feeble resistance in their demoralized
state and that, after being badly cut up by the horsemen, they had
surrendered. A little later Ali and his Arabs returned, unwounded,
swaggering a bit, and gave them a lurid account of the fight.




                             CHAPTER XXVII.
                             ATHENSI FALLS.


After all these events culminating in the rescue of Bob and the
disastrous rout of the Janissaries at Korakum, Mr. Hampton decided
instead of returning to civilization without having accomplished his
main objective--namely, the exploration of the ruins of Korakum and the
gaining of entrance to Athensi--to stay and await the result of the
revolution.

The Korakum expedition had been timed by the Oligarchs to coincide with
an attack in force launched through the mountains against Captain
Amanassar's main body of revolutionists in the field. There, too, the
Janissaries had been unsuccessful. Though not beaten so decisively as at
Korakum, they had been unable to penetrate the strong position held by
the rebels and, sullen and alarmed at the unexpected strength of the
opposition, they had fallen back to the shelter of the walls of Athensi.

In their retreat they carried off all the livestock for miles from the
country between Captain Amanassar and the city, stripping the poor
peasants of everything, and herding the young men into the city while
leaving the children and the old people to live as best they might.

Mr. Hampton made a trip to Captain Amanassar's camp, into which the
stricken country people from the devastated districts were making their
way, and on his return reported many pitiable sights. The rebel leader's
assurance that the fall of Athensi, in view of the two disasters to the
arms of its defenders, was inevitable, caused the American to decide to
stay.

He was moved by more than an explorer's interest, moreover. Deeply
stirred by the ideals of these young Athensians, sons of a semi-savage
race dating from the dawn of time, who were resolved to redeem their
country from the rule of the Oligarchs who so long had held it in
thrall, he felt that his engineering experience would be valuable in the
final siege of the city and that later his knowledge of world affairs
would be worth much to Captain Amanassar when the latter and his
compatriots came to the point of opening communication with the outside
world.

Week by week the lines about Athensi grew tighter, with every sally of
the Janissaries repulsed. Reports from friends within the city, where
the revolutionists had many adherents, continued to reach the rebel
camp, and all were to the effect that famine was beginning to raise its
head amid the crowded population.

That great numbers of his countrymen should be starved to death or die
of plague, for sickness also broke out in Athensi, was not Captain
Amanassar's object. On several occasions, he made overtures to the
Oligarchs looking to the surrender of the city on terms which would
spare their lives, but these were all rejected. The rulers of the priest
clan could not bring themselves to a realization that at last the power
they had exercised through uncounted centuries was seriously threatened,
and seemed bent on involving all in ruin rather than continue to live
shorn of power. To storm Athensi was an impossibility for Captain
Amanassar's numerous but ill-equipped army, and apparently the only
thing to do was to play a waiting game.

Such a course, however, was repugnant to the rebel leader, whose heart
bled for the miseries of the cooped-up population, and he sought by
every known method of appeal to prevail on those residents who managed
to steal out of Athensi and reach his camp, to bring about an uprising
in the city which would open its gates to his forces.

At length, when the miseries of the city reached a point too great to be
borne any longer, his arguments prevailed. A half dozen of his
stoutest-hearted aides entered Athensi with a drove of lean cattle,
announcing boldly they had been burned out by the rebels and came to the
city for shelter. They disappeared amid the city warrens after being
admitted at the great gate, and then scattered to rouse the city to
fever pitch.

That night the Janissaries, going to change guard on the walls, were
attacked as they passed through the streets, and were driven back to the
shelter of the Inner City. The guard at the great gate was surprised and
overcome, and the gates opened to admit a force of picked warriors from
the rebel ranks, who had stolen up under cover of darkness.

The Janissaries posted on the walls in the vicinity of the gate were
overcome, although fighting desperately, and before help could reach
them from other parts of the walls, the main force of the rebels, which
had moved up by forced marches, entered the city.

Many of the Janissaries were cut down as they fell back to the Inner
City, where their heartless comrades refused to open the gates to admit
them lest the rebels also force their way in.

Dawn found Athensi in the possession of Captain Amanassar's forces, with
the Inner City beleaguered on every side, and its fall only a matter of
time. Three weeks it managed to hold out and then its defenders weak
from hunger, were forced to seek unconditional surrender. The Oligarchs
were imprisoned to stand trial later for their crimes, and the surviving
Janissaries were disarmed and, although their lives were spared, they
were put to work as state peons repairing the ravaged countryside.

Bob, Jack, Frank and Roy Stone followed the first wave of the attack
into Athensi in a company of 200 rebels commanded by Jepthah. At Bob's
special request, this group made its way through the tumultuous streets
to the Coliseum. It was a moonless night, and the great amphitheater lay
dark and mysterious outside the walls of the Inner City.

Around those walls raged a furious battle but in the Coliseum itself,
which the Janissaries had no idea of defending, all was silent. That is,
until the rebels with Bob at their head, clad again in the gladiator's
armor he had worn on being rescued, entered the arena with their
wavering torches.

The tumult of the desperate fighting within the city was reduced to a
murmur down there, on the sand, at the base of those towering tiers of
seats. Yet here, too, it had penetrated and the poor captives, locked in
their quarters for the night, and awaiting the coming of the Sacrificial
Games, now only a week away, were awake and moving about restlessly.

As the light of the torches fell through the massive bars of the great
door set in the solid stone of the wall, and penetrated the interior of
the single great room where all the alien gladiators were quartered and
where Bob, too, had lived, the poor fellows crowded forward.

They did not know what the tumult in the city and now the arrival of
this armed force portended, but Bob was easily recognizable in his armor
and made friendly signs indicating he had come to release them. At the
same time, men armed with stout axes and wrenching bars attacked the
gate. It was stubborn and resisted all assaults a long time but
eventually gave way, and then the slaves threw themselves at Bob's feet
and tried to kiss his hands. To these men, most of whom were Negroes,
although a few Berbers and Tuaregs were in the number, Bob's sudden
rescue by airplane had appeared as a miracle. And now his return to
release them had an even greater effect on their primitive
intelligences.

While this was going on Jepthah headed another party which broke down a
similar gate on the other side of the arena, behind which were confined
the young Athensians destined to fight the slaves in the Sacrificial
Games. To one or two of them he was known, and when he spread the word
of the success of the revolution the joy of these young fellows,
snatched from their families by the Oligarchs to go to death, knew no
bounds.




                            CHAPTER XXVIII.
                              CONCLUSION.


After the final capitulation of the Oligarchy, Mr. Hampton and the
members of his party went to live in quarters assigned them in one of
the palaces of the Inner City. It was an age-worn stone structure of
immensely thick walls, two stories in height, and covering five acres of
ground. In it were hundreds of rooms and apartments, sumptuously
appointed with many luxuries.

"It's all right, this business of living in a palace," said Bob, one
day. "Just the same I for one can never accustom myself to living in a
tomb. And that's what this seems like, with its old stone walls and
courts and secret passages, and what not."

With this opinion, Jack and Frank were in hearty agreement. Likewise Roy
Stone, who after repairing his airplane had flown it to the plain
outside Athensi where it rested now with just sufficient fuel to carry
him out of the desert when the time came to depart. Departure, however,
he kept putting off from time to time at the insistence of his friends.

Ali and his Arabs continued to stay with Mr. Hampton, the wounded
members of the party now fully restored to health.

In the Great Library of Athensi, the biggest building in extent within
the Inner City, were found as the revolutionists had predicted many
thousands of manuscripts or papyrus rolls written in the ancient mother
tongue of Atlantis of which Athensian was a corruption. Few of the young
nobles among the revolutionists ever had been within the library before,
as the ancients of the Oligarchs had guarded it jealously. They were
even more eager than Mr. Hampton to browse, if that word can properly be
employed in this connection. But when they came to examining the rolls,
they found that it was only with difficulty they could here and there
decipher a word.

However, the similarity of languages was such that in time the mother
tongue could be learned and the treasured knowledge of this most ancient
of libraries in the oldest living city on earth, could be unlocked and
given to the world. To the task of learning the language and of putting
the library in order, Captain Amanassar who had been elected President
of the new republican government, assigned Amonasis, Amrath and two
dozen assistants, comprising the best educated of the young
revolutionists. Eagerly, they began their task.

At length, with a story that later was to astound not only the
scientific world but all civilization, Mr. Hampton, finding his advice
no longer was required, decided to depart. They had been absent from
home five months. Bob and Frank were overdue for their Senior year at
Yale. Mr. Hampton was to be the unofficial representative of the
Athensian government to the United States, and was to pave the way for
official representatives to be sent to the various world capitals by
making public his account of events.

In addition, he was to interest capitalists in developing the resources
of the country, and in building a railroad linking up Athensi with the
Cape-to-Cairo Railroad.

He promised to return the following year, estimating it would require
that length of time at least to perform his various commissions. On his
return, the boys planned to accompany him and to build a great radio
station at Athensi, which would put the mountain people in touch with
all the world.

True to his promise, they did return the following year, carrying to
Athensi a great caravan of supplies for the erection of a completely
equipped radio sending and receiving station. These supplies were taken
up the Niger by boat and finally across the desert by camel.

But after finishing the erection of the station, the three Radio Boys
set out on an exploring expedition through the heart of Africa in the
interests of a new motion picture producing corporation among the
backers of which were both Mr. Temple and Mr. Hampton. And the
adventures which befell them upon this 5,000 mile journey through jungle
wilds and in coming into contact with savage men and beasts, were
numerous and varied.

All will be duly chronicled in "The Radio Boys in Darkest Africa." Until
then, let us bid them good-bye.


                                THE END.


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Frank Chadwick and Jack Templeton, young American lads, meet each other
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In this series we follow the fortunes of two American lads unable to
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  CAPTAIN JACK LORIMER; or, The Young Athlete of Millvale High.

  Jack Lorimer is a fine example of the all-around American high-school
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  JACK LORIMER'S CHAMPIONS; or, Sports on Land and Lake.

  There is a lively story woven in with the athletic achievements, which
  are all right, since the book has been O. K'd. by Chadwick, the Nestor
  of American Sporting journalism.

  JACK LORIMER'S HOLIDAYS; or, Millvale High in Camp.

  It would be well not to put this book into a boy's hands until the
  chores are finished, otherwise they might be neglected.

  JACK LORIMER'S SUBSTITUTE; or, The Acting Captain of the Team.

  On the sporting side, this book takes up football, wrestling, and
  tobogganing. There is a good deal of fun in this book and plenty of
  action.

  JACK LORIMER, FRESHMAN; or, From Millvale High to Exmouth.

  Jack and some friends he makes crowd innumerable happenings into an
  exciting freshman year at one of the leading Eastern colleges. The
  book is typical of the American college boy's life, and there is a
  lively story, interwoven with feats on the gridiron, hockey,
  basketball and other clean honest sports for which Jack Lorimer
  stands.


                         The Girl Scouts Series

                            BY EDITH LAVELL

              [Illustration: The Girl Scouts' Canoe Trip]

A new copyright series of Girl Scouts stories by an author of wide
experience in Scouts' craft, as Director of Girl Scouts of Philadelphia.

               Clothbound, with Attractive Color Designs.
                         PRICE, 65 CENTS EACH.

  THE GIRL SCOUTS AT MISS ALLEN'S SCHOOL
  THE GIRL SCOUTS AT CAMP
  THE GIRL SCOUTS' GOOD TURN
  THE GIRL SCOUTS' CANOE TRIP
  THE GIRL SCOUTS' RIVALS


                      Marjorie Dean College Series

                           BY PAULINE LESTER.
         Author of the Famous Marjorie Dean High School Series.

            [Illustration: Marjorie Dean, College Sophomore]

Those who have read the Marjorie Dean High School Series will be eager
to read this new series, as Marjorie Dean continues to be the heroine in
these stories.

                  All Clothbound.    Copyright Titles.
                         PRICE, 65 CENTS EACH.

  MARJORIE DEAN, COLLEGE FRESHMAN
  MARJORIE DEAN, COLLEGE SOPHOMORE
  MARJORIE DEAN, COLLEGE JUNIOR
  MARJORIE DEAN, COLLEGE SENIOR


                    Marjorie Dean High School Series

                           BY PAULINE LESTER
           Author of the Famous Marjorie Dean College Series

          [Illustration: Marjorie Dean, High School Freshman]

These are clean, wholesome stories that will be of great interest to all
girls of high school age.

                  All Cloth Bound    Copyright Titles
                          PRICE, 65 CENTS EACH

  MARJORIE DEAN, HIGH SCHOOL FRESHMAN
  MARJORIE DEAN, HIGH SCHOOL SOPHOMORE
  MARJORIE DEAN, HIGH SCHOOL JUNIOR
  MARJORIE DEAN, HIGH SCHOOL SENIOR


                       The Camp Fire Girls Series

                          By HILDEGARD G. FREY

         [Illustration: The Camp Fire Girls in the Maine Woods]

A Series of Outdoor Stories for Girls 12 to 16 Years.

                  All Cloth Bound    Copyright Titles
                          PRICE, 65 CENTS EACH

  THE CAMP FIRE GIRLS IN THE MAINE WOODS; or, The Winnebagos go Camping.
  THE CAMP FIRE GIRLS AT SCHOOL; or, The Wohelo Weavers.
  THE CAMP FIRE GIRLS AT ONOWAY HOUSE; or, The Magic Garden.
  THE CAMP FIRE GIRLS GO MOTORING; or, Along the Road That Leads the
          Way.
  THE CAMP FIRE GIRLS' LARKS AND PRANKS; or, The House of the Open Door.
  THE CAMP FIRE GIRLS ON ELLEN'S ISLE; or, The Trail of the Seven
          Cedars.
  THE CAMP FIRE GIRLS ON THE OPEN ROAD; or, Glorify Work.
  THE CAMP FIRE GIRLS DO THEIR BIT; or, Over the Top with the
          Winnebagos.
  THE CAMP FIRE GIRLS SOLVE A MYSTERY; or, The Christmas Adventure at
          Carver House.
  THE CAMP FIRE GIRLS AT CAMP KEEWAYDIN; or, Down Paddles.

For sale by all booksellers, or sent postpaid on receipt of price by the
                               Publishers

                           A. L. BURT COMPANY
                  114-120 EAST 23rd STREET    NEW YORK




                          Transcriber's Notes


--Copyright notice provided as in the original--this e-text is public
  domain in the country of publication.

--Silently corrected palpable typos; left non-standard (or amusing)
  spellings, punctuation, and dialect unchanged.

--Added a Table of Contents based on chapter headings.

--In the text versions, delimited italics text in _underscores_ (the
  HTML version reproduces the font form of the printed book.)