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[Illustration: THE DUEL IN MIDAIR.]




AIR SERVICE BOYS OVER THE ENEMY'S LINES

OR

THE GERMAN SPY'S SECRET

BY

CHARLES AMORY BEACH

Author of "Air Service Boys Flying for France"

ILLUSTRATED BY

ROBERT GASTON HERBERT

THE WORLD SYNDICATE PUBLISHING CO.

CLEVELAND, O. NEW YORK, N.Y.




Copyright, 1919, BY

GEORGE SULLY & COMPANY

Printed in the United States of America

by

THE COMMERCIAL BOOKBINDING CO.

CLEVELAND, O.




AIR SERVICE BOYS OVER THE ENEMY LINES

CONTENTS
 Chapter                                              Page
       I.  Back of the Trenches                          1
      II.  The Winged Messenger                         10
     III.  A Spy Baffled                                19
      IV.  Praise From the General                      27
       V.  The Strange Warning                          35
      VI.  Looking Backward                             45
     VII.  The Great Day Arrives                        53
    VIII.  Over the Enemy's Lines                       61
      IX.  Winning His Spurs                            70
       X.  After the Battle                             78
      XI.  A Show on the Front                          85
     XII.  Clowns on the Wing                           94
    XIII.  More Work in Prospect                       103
     XIV.  Off on a Daring Mission                     113
      XV.  The Moonlight Flight                        120
     XVI.  Landing Close To Metz                       129
    XVII.  More Trouble for the Chums                  137
   XVIII.  The Lone House by the Roadside              144
     XIX.  A Nest of Spies                             153
      XX.  Jack Climbs a Wall                          162
     XXI.  In the Old Lorraine Château                 171
    XXII.  Facing More Difficulties                    181
   XXIII.  Left Behind in the Enemy's Country          191
    XXIV.  Troublous Times for Jack                    200
     XXV.  Back to Safety--Conclusion                  208




AIR SERVICE BOYS OVER THE ENEMY'S LINES




CHAPTER I

BACK OF THE TRENCHES


"Tom, what do you suppose that strange man who looked like a French
peasant, yet wasn't one, could have been up to late yesterday
afternoon?"

"You mean the fellow discovered near the hangars at the aviation camp,
Jack?"

"Yes. He seemed to go out of sight like a wreath of smoke does. Why, if
the ground had opened and swallowed him up, once the hue and cry was
raised, he couldn't have vanished quicker. I wonder if what they say
about him can be true?"

"That he was a German spy? Anything is possible in war times."

"I guess you're right there. German secret sympathizers, and spies in
the bargain, seemed to bob up all over the United States before we
crossed the ocean to do our fighting for France as aviators."

"They certainly were busy bees, Jack, blowing up munition-works, trying
to destroy big railroad bridges so as to cripple traffic with the Allies
over here; burning grain elevators in which France and Great Britain had
big supplies of wheat stored; and even putting bombs aboard ocean liners
that were timed to explode days later, when the boat would be a thousand
miles from land."

"Over in France here they make short work of spies, I've heard, Tom!"

"Yes, it's a drumhead court martial and trial. Then, if the man or woman
is found guilty, the spy goes out with a firing squad to the most
convenient stone wall. They never return, Jack."

"Whee! that sounds like war times, doesn't it? And to think the two of
us are right on the firing line, in the midst of all the scrapping. But,
Tom, tell me, why should a tricky German spy want to hang out around the
aviation field? He could hardly expect to pick up any news there that
would be worth taking across the lines to the headquarters of the Crown
Prince before Verdun."

"Don't be too sure of that, Jack. Perhaps he might learn of some
contemplated bombing expedition, like that one we went on not so long
ago." And Tom Raymond smiled slightly.

"They are a mighty clever bunch, those spies," admitted Jack Parmly.

"Why, Jack, half of the successes of the Kaiser's armies on all fronts,
Russia, France and Rumania, can be laid at the door of his secret
agents. They seem to be everywhere, trying to foment internal troubles,
strikes, and discontent, so that when the Germans strike hard they meet
a divided enemy in front."

"Well, I certainly wish we had caught that fellow."

"You were in the crowd, you told me, that scoured the whole neighborhood
in search of him."

"That's right, I was. But say, he proved too foxy for us all. Anyway, we
failed to find the rascal. Then night came on, when we had to give our
man-hunt over. And to think that I even glimpsed the fellow's face in
the bargain before the alarm went out!"

"Then you'd know him again perhaps, Jack, if ever you met him?"

"I think so. Though I suppose these spies have ways of changing their
looks at times. But, to change the subject, Tom, it strikes me neither
of us is groaning under the weight of game so far on our little side
hunt." And Jack Parmly grinned.

"Oh, I didn't really expect to run across anything, though that French
peasant assured us there were still some rabbits in the burrows over
here, three miles back of our sleeping quarters. That's why, with a day
off-duty, I took a notion to borrow an old Belgian-made double-barrel
shotgun he owned, and walk out here."

"More to stretch our legs and get the kinks out, than anything else, eh,
Tom?"

"That's it, Jack. Don't you remember that while we were training at the
aviation school at Pau we used often to walk from the town, eight miles
distant, until we sighted that famous little old red barn at Pau, where
the Wright Brothers conducted some of their experiments in flying
heavier-than-air machines. That was some little hike."

"Then too, Tom, I guess we wanted to get together by ourselves for a
change, so we could talk about our folks at home in little old
Bridgeton, U. S. A.," went on Jack Parmly with a sigh. "All the fellows
of the Lafayette Escadrille are mighty kind and sociable, but there are
times when a fellow gets homesick. Just remember that we have been over
here many months now. It seems years to me, Tom."

"Say, I hope you are not homesick enough to want to go back, old
fellow?"

"Not me, Tom. I made up my mind to stick it out until we whip the
Kaiser. But already I can see it'll never be an accomplished fact until
Uncle Sam throws his sword into the scales. And any day now something
may drop."

"Yes, matters are at an acute stage in Washington, that's sure. All
France, bled nearly white in two-and-a-half years of war, is praying
that the day may come soon."

After that the two athletic looking young Americans, dressed in the
uniform of the French aviation corps, fell silent for a brief time.
They, however, continued to trudge over the devastated fields, looking
this way and that for any sign of a stray rabbit that had escaped the
general slaughter.

It was just previous to the world-stirring session of Congress, when the
President made his thrilling speech that sounded almost from end to end
of the world, and put America in line for the cause of democracy.
Anxious days those were across the ocean, anxious not only in France,
Italy and Great Britain, in Serbia, Rumania, Greece and Russia, but in
the Central Empires, also.

For well did those in Teutonic authority know, in spite of their vain
boasting, that once great America decided, the thing was bound to be
done, sooner or later. Never in the course of her history has our
republic been on a losing side. Her wars have invariably brought
eventual victory to her arms, because she has never once fought for an
unjust cause.

These two vigorous young fellows were fair samples of those enterprising
Americans who found it impossible to sit idly by. They could not await
the slow course of events that was bound to carry our country into the
world war on the side of the Allies, in spite of all the powerful
counter currents among the pro-German citizens at home.

Dozens of the brightest of flying men from the States had gone over and
offered their services to France, the country they loved. In time there
came to be so many, that from the ordinary French Flying Corps there was
formed a unit entirely made up of Americans.

This, in honor of the one great Frenchman whom Americans most honor at
home, was called the Lafayette Escadrille. Some of its members had
become famous at their profession. Names like those of Lufbery, Thaw,
McConnell, Chapman, Prince, Rockwell, Hill, Rumsey, Johnson, Balsley and
others became household words among readers of the great dailies in the
States.

Tom Raymond was the son of a man who had gained fame as an inventor.
When the war broke out he started work on numerous inventions, some of
which were calculated to become terrible agents for the destruction of
human life. Then Mr. Raymond's mood changed, and he set to work to
conceive a wonderful stabilizer for airplane use that would save myriads
of lives, and if adopted by Uncle Sam was likely to help win the war for
the Allies.

Just when this invention was finished a drawing of one of the parts was
stolen by a German spy. Later on, after Tom and his chum, Jack Parmly
had decided to become war aviators, having already had considerable
aviation experience, they went to the flying school conducted by the
Government in Virginia.

From there in course of time they crossed the Atlantic and entered the
famous French school at Pau. Then, having mastered the science of flying
sufficiently to be sent to the front, they had joined the Lafayette
Escadrille, as related in a previous volume entitled "Air Service Boys
Flying for France; or The Young Heroes of the Lafayette Escadrille."

Tom in particular seemed to have a great career ahead of him, unless
some unfortunate accident, or possibly a Teuton pilot, cut it short, as
had happened in the cases of Rockwell, Prince, McConnell and Chapman.
Every one knew he possessed genius of a high order, and that it would
not be long before Tom Raymond might anticipate gaining the proud title
of "_ace_," which would indicate that he had defeated five enemies
at different times, and put them entirely out of the running.

Tom was already a corporal in the French service, and expected before a
great while to be given the privilege of wearing the chevrons of a
sergeant. Jack had not progressed so rapidly but was doing well.

And now to return to the young aviators during their walk.

"I reckon we've gone far enough, Jack," Tom remarked presently. "Our
friend Jean may have been telling the truth when he said there were
still a few bunnies left alive in this war-racked section of country,
but I can see they've got the good sense to stick to their burrows
during the daytime. We won't be burdened with our bag of game on the
return trip."

"Yes, that's always the trouble, when you go out after rabbits and
haven't any hound along to get them up and bring them within gunshot,"
grumbled Jack.

"But we've had a good walk," returned his companion; "and for a time we
managed to get away from that terrible explosion of shells, and big-gun
firing. We ought to be thankful for our little time off, Jack."

"Oh! I'm not really complaining," remarked the other young aviator, with
a whimsical expression on his good-natured face. "But don't you know I
hate to go back without having fired even one shot." He stopped short
and pointed upward. "Hold on, Tom; there's some kind of bird going to
pass over right now! Crow or anything, please bring it down! I'll
promise to eat it, no matter what it is."

Laughingly Tom threw the gun up to his shoulder, and the next instant
the report sounded. It seemed almost contemptible, after listening to
the roar of those monster shells exploding for so long.

The bird fell fluttering in a heap. Tom evidently was a fair marksman,
for it had been moving swiftly over their heads at the time he fired.
Jack ran forward and picked the game up. As he did so he gave utterance
to exclamations that naturally excited the curiosity of his chum. So
Tom, after reloading his gun with a fresh shell, waited for Jack to
rejoin him, which the other did, his face full of mystery.




CHAPTER II

THE WINGED MESSENGER


"What do you call this, Tom? A queer sort of crow, I'd say. Looks more
to me like the blue-rock pigeons Sam Becker used to raise at home," and
so saying Jack held up the still quivering bunch of feathers.

Tom took one quick look, and then a startled expression flitted across
his face.

"Just what it is, Jack!" he hastened to say. "A homing pigeon in the
bargain! You can tell that from the bill and the ring around the eyes."

Jack in turn became aroused.

"A homing pigeon, is it?" he ejaculated. "Why, birds like that are used
for carrying messages across the lines! Some of our airplane pilots have
told me that sometimes they take a French spy far back of the German
front. When he had made an important discovery he would write a message
in cipher, enclose it in a tiny waterproof capsule attached to a ring
about the pigeon's leg, and set the bird free. Inside of half an hour it
would be safe back in its loft, and the message on the way to French
headquarters."

He lifted one limp leg, and then the other.

"Look here, it's got a message, as sure as anything!" Jack exclaimed.

Tom leaned forward and took the bird in his hand, dropping the gun
meanwhile. He carefully took off the gelatine capsule, and from it
extracted a delicate piece of tough paper, which he spread open. There
were a series of strange marks on the paper, of which neither of the air
service boys could make anything.

"Looks like hieroglyphics, such as you'd expect to find on an Egyptian
tomb or in the burial places under the pyramids," complained Jack, after
he had stared at the lines in disgust for a brief period of time.

"It's a cipher of some kind," explained Tom, seriously. "With the key
all this would resolve itself into some sort of communication, I
suppose, connected with valuable information concerning the French
armies here at Verdun."

"Then it was made by a spy!"

"No question about that part of it," came the ready reply.

"This carrier pigeon with this message, was on its way across to some
point in the rear of the enemy line when you fired, and brought the poor
little thing down in a quivering heap, I'm sure that's it," continued
the other.

"Yes. And so after all it's turned out to be a lucky thing you chanced
to see the bird coming along, Jack, and begged me to knock it down so we
could show some sort of game when we got back to camp."

"What ought we do with this message?" asked Jack, accustomed to
depending on his more energetic chum in many cases; though when left to
his own resources he could think for himself, as had frequently been
proved.

"I shall see that it gets to French headquarters, with an account of the
singular way we ran across it," Tom told him.

"Do you think it would be possible for any one there to translate this
cipher of the German secret code?"

"Why not?" Tom demanded. "They are clever people, these wideawake
French, and I shouldn't be at all surprised if they turned this incident
to some good use."

"How?"

"Oh, it could be done in many ways. Suppose they found the key to the
code. Don't you see how a fictitious message could be sent on in some
way, if they could bag another pigeon from the same coop? They might
even coax the Germans to deliver a furious attack at a supposed weak
place in the line, which would of course be heavily guarded."

"That would be something worth while!" exclaimed the other with glowing
eyes. "Lead them into a trap, where they would be mowed down like ripe
grain, terrible as that sounds!"

"Yes, that's the idea I had in mind. But it would depend on several
things. First of all would come the successful solving of this cipher
code."

"Yes, and then the finding of another homing pigeon," added Jack. "I
wonder if the fellow who released that bird could have a lot more of the
same kind hidden away somewhere around back here."

"I was just going to suggest that we take a turn toward the south, and
look around a bit before going back to camp. Do you feel equal to it,
Jack?"

"What, me! Tom? Why, I'm as fresh as a daisy! This business has made me
forget there's such a thing as getting tired walking."

"Let's see, we stood here when I fired," continued Tom reflectively,
"and you walked straight to where the bird dropped. That would make the
direction due northwest by southeast. How about that, Jack?"

The other took a survey, and then pointed with his hand.

"When I saw the bird coming first of all, Tom," he finally remarked, "it
was just showing up over that clump of trees killed by gunfire. And it
was heading as straight as can be for us."

"Yes," Tom went on to say, "because a homing pigeon on being released
will rise to a certain height and take its bearings. Then it starts in a
bee-line for its loft, whether that is five miles away or hundreds of
miles. Some peculiar instinct tells it in which way home lies. It seldom
if ever goes astray. Sometimes birds have made a thousand miles, and
shown up at their home coop days after being set free."

"Well, then, the man who threw it into the air, after fastening this
cipher message to it, must be over to the southeast of us," affirmed
Jack.

"The bird was released within five minutes or so of the time I fired,"
Tom told his chum. "It's even possible the spy may have heard the report
of my gun."

"Tom, why not try to capture that spy?" asked Jack, eagerly, ready for
any sort of excitement.

The young aviators started off, walking briskly. They kept their eyes
alertly open as they proceeded. At the same time, on Tom's suggestion,
they continued to act as though still looking for game, even
investigating at a burrow that certainly was used by rabbits, as the
tracks plainly indicated.

Tom never deviated from a direct line due southeast. He knew that their
best chance of making a valuable discovery lay in finding the place
where the carrier pigeon had been released, to fly across the lines to
its home loft. This might be many miles to the rear of the fighting
front, even on Lorraine territory, in the neighborhood of the fortified
city of Metz itself.

The two passed over a mile without making any sort of discovery, Jack,
who did not possess quite as determined a nature as his comrade, was
already commencing to make certain sounds akin to complainings, as
though he felt keenly disgruntled because of their lack of success.

"Guess we'll have to give it up, Tom," he finally remarked.

"Wait," said Tom. "Before doing that let's investigate that old
shattered farmhouse over yonder."

"Hello!" exclaimed Jack, plucking up some fresh interest, "have you
located one of those remains of a building, then? I was coming to
believe there wasn't so much as a broken wall left standing for a space
of five square miles, so complete has been the destruction. But I see
what you mean, Tom."

They walked ahead again, and approached the ruined farmhouse. It had
been riddled through and through by shot and shell. Three-fourths of the
original building lay in piles, the stones heaped up as they had fallen.

"Queer, isn't it, that the kitchen part escaped the smashing fire, and
still stands," observed Jack. "I warrant you this is the only part of a
building left around here. Tom, would our spy be likely to take up his
headquarters in such a place as this, do you think?"

"I don't know," came the answer. "We can soon find out."

"He might feel desperate enough to open fire on us," suggested Jack,
though he did not shrink or hold back when Tom advanced; for Jack Parmly
did not have a drop of cowardly blood in his veins.

Tom turned and waved his hand as though beckoning to others who might be
coming after them. He even called out in his best French, as if there
were a dozen back of him, that there was a possibility of securing at
least a drink of cold water at the old-fashioned well with a sweep that
stood near the kitchen of the ruined farmhouse.

"Good idea, Tom!" commented the other, chuckling with amusement. "If he
gets the notion in his head that we are legion he won't be so apt to
blaze away at us, knowing it would mean a short shrift for him. He may
prefer to play the poor French peasant part, and try to pull the wool
over our eyes."

Presently they arrived at the door. It was hanging from one hinge, and
the entire place presented a vivid picture of the utter desolation cruel
war always brings in its train.

Tom's first act before entering was to look down at the ground just
before the door. Some intuition told him that if the place had been
recently occupied they would possibly find some evidences of the fact in
the earth.

"See there, Jack!" he suddenly exclaimed, as he pointed down close to
his feet. "Fresh tracks, and made by a man's shoes in the bargain!"

"Some one has been in here for a fact, Tom, and I wouldn't be afraid to
wager he saw us coming and cleared out in a hurry. He could have skirted
those bushes, and got clear easy enough. Do you think it could have been
the same chap who freed that pigeon?"

"No doubt about it," and Tom, stooping, picked up some small object.
"See, here's a feather that was sticking to that dead weed. It's from a
bird of the same color as the pigeon, perhaps from the very one I've got
in my pocket."

"That settles it," snapped the pleased Jack. "I must say you're a clever
hand at finding these things out. I'd have never dreamed of looking down
at my feet, but blundered right into the shack to see if----Oh! What do
you think of the luck we're in this day, Tom? See what stands there on
that poor old three-legged table!"

Jack's excitement was natural, as Tom readily understood when he looked;
for there was a small basket or cage made from oziers or willow wands;
and inside this they could see two blue gray homing pigeons, mates to
the one Tom had shot only a short time before!




CHAPTER III

A SPY BAFFLED


Both young aviators stared at the wicker cage containing the two
pigeons. The birds had been still up to then, but now commenced to make
cooing sounds, as though pleased at having human company. Apparently
they were inclined to be sociable, as Jack afterwards put it.

"So he discovered us coming along," Jack went on to say, "and skipped
out in such a hurry he didn't have time to carry away the cage with
him."

"He must have climbed out of this window in the side of the wall,"
observed Tom. "We could have seen him if he had used the door. Yes,
there are footprints underneath the window. He ran down behind those
bushes and reached the stone wall that leads to the broken country and
what is left of the woods."

"The chances are he had all that mapped out beforehand," suggested Jack.
"Surely a spy has always to keep a door open for retreat."

"Yes. Why not? They take their lives in their hands every time they
enter the hostile lines, and you can't blame a man for wanting to live a
little longer, especially if he believes he can serve his country."

"Perhaps he hasn't got such a good start but that we could overtake him
if we went after him now," suggested Jack.

"We might take a turn that way," his chum agreed. "But not too far
afield. We didn't start out to search for spies, and we've only got a
single gun between us. Even my automatic was left behind, because I
didn't expect to have any use for it, and get tired carrying the thing,
with its belt."

"But these pigeons here, Tom?"

"We can leave them until we get back. That's one reason why I don't want
to get out of sight of the place. He might make a round, and carry the
birds away while we were engaged in a hunt half a mile off. And it may
be of much more importance that those live birds arrive in the French
camp than that we should bag the spy."

"I get you, Tom; so let's commence our little man-hunt right away."

The two friends set off. Tom tried to follow the course he believed the
spy must have taken on quitting the old farmhouse ruins. That his
reckoning was clear he proved several times by pointing out to his
companion plain evidences that some other person had passed along the
way before them.

Here the marks of shoes could be detected in the soft earth. A little
further on, and at a point where the man must have crawled in order to
keep from being seen, they found tracks where his toes had dragged
along, as well as the indentation of his knees in the soil.

Presently they arrived at the terminus of the stone wall, about the only
thing remaining intact connected with the French farm. There was not a
single tree showing signs of life in that patch of sombre forest; where
shell-fire had failed to do the work of destruction a malicious hand had
girdled the trunk with a keen-edged tool, and thus encompassed the doom
of the trees.

Tom came to a pause.

"I reckon we've come far enough," he said, taking a look over toward the
fragment of a house on the slight elevation, which could just be seen
from their present position.

"I'd have liked to catch up with that duck and march him back to camp,
along with his feathered messengers," Jack grumbled disappointedly.
"Somehow I hate and despise a spy above all created things."

The youths set their faces once more in the direction of the ruins,
where they soon arrived. Jack half feared that in spite of them the cage
and its feathered inmates had been spirited away. He hastened inside
ahead of his companion and then called out cheerily:

"It's all right, Tom, and nobody at home. Here's the wicker cage and the
pigeons, just as we left them!"

"As the afternoon is passing, and we have a long distance to go, we'd
better be making a start," Tom remarked, when he reached the open door.

"Let me carry the pigeon cage, Tom, as you have the gun," suggested
Jack, after slipping his hand through the ring at the top. "Say, perhaps
the boys won't give us a laugh, to see what queer game we've brought
back from our hunt!"

They left the ruins of the once peaceful farmhouse behind them, and
commenced retracing their steps. Tom was too old a hand at hunting to
get lost. He had kept his bearings through the whole tramp, no matter
how many turns they took in examining some promising ground where rabbit
burrows might be found. On this account then he would have no difficulty
whatever in leading his comrade straight back to the villa in which the
entire Lafayette Escadrille of American fliers was quartered.

They were passing along about half a mile from the wrecked farmhouse
kitchen, and not far from the spot where Tom made his successful shot,
when without warning the report of a gun came to their ears. Jack
involuntarily ducked his head.

"Say, did you hear that whining sound just over us, Tom? That was caused
by a bullet skipping past!"

Tom for answer dragged his chum down behind a fringe of dead bushes that
chanced to lie close by.

"It was a bullet, all right, Jack," he replied, not without a tremor in
his voice, for this thing of being made a target by some murderous
unseen person was a new and novel experience.

"Do you suppose it was fired by the man who owns these pigeons?" further
questioned Jack, though showing no intention of loosening his grip on
the wicker cage.

"It could hardly be any one else. He has dogged us this far, or else
just happened to catch sight of us. That shot was fired from a distance,
and if we take a notion to run he couldn't possibly hit us. But we might
as well make use of this fringe of bushes to creep some way off. Then
we'll get on our feet and put out for home at full speed."

This they proceeded to do without further delay. When it was no longer
possible to utilize the bushes for cover, they sprang to their feet and
ran. Jack fully anticipated hearing other shots--yes, and perhaps having
more leaden missiles singing their vicious songs about his head. But he
was agreeably disappointed in his expectations, for not a report came.

Evidently the spy had gone away, thinking discretion the better part of
valor. He may have noticed that they were in uniform, and armed in the
bargain.

Later on the air service boys moderated their mad pace, and as there
seemed to be no further signs of danger they finally fell into a walk.
Still neither of them lagged, but kept up a brisk pace, Jack casting
numerous apprehensive glances over his shoulder, haunted by a lingering
suspicion that the spy might yet give them trouble.

They came through safely at last. The villa in which the American fliers
were quartered was reached, and seemed to be deserted at that hour in
the afternoon. Everybody must be busy at the front, the boys concluded,
for the din was more distracting than usual.

"We picked out a bad day for getting off, I'm afraid, Tom," Jack sighed.
"They told us there was nothing big in prospect; but since we started
out on our hunt I guess the Huns have put up something of size. And the
boys will be in the thick of it all too! We might have had a share if
we'd been on duty to-day."

"Brace up, Jack," chided his chum. "For all you know, what we've done
may turn out to be ten times more important than all the work of the
entire escadrille to-day. These captured birds and that cipher message,
represent possibilities beyond anything you or I can know. Leave all
that to the general."

"When do you mean to see him, Tom?"

"As soon as I can arrange it. And you're coming with me when I get the
summons to his headquarters, depend on that, Jack. Your part in this
affair is just as important as mine."

Tom put the cage with its cooing inmates in their room. Then he started
out to try to get into communication with the commanding general. He had
met him once by mere chance, but he hardly believed General Petain would
remember him in the least.

The action was about over for the day. The Crown Prince had once again
thrown a heavy storming party forward in the endeavor to make a breach
in the French lines, through which he could pour the veteran reserves he
had in waiting. But, as had often happened before, he counted without
his host; and when the sun went down all he had to show for his stroke
was a greatly increased casualty list.

The French could not be moved.

Tom understood how to go about it, and in the end managed to get an
obliging French captain whom he knew very well, to carry a message to
the commander-in-chief to the effect that he had news of great
importance to communicate. Just as Tom expected would be the case, this
brought back a speedy answer.

"You are both to come with me, young Messieurs," said the captain, his
eyes sparkling with interest, for Tom had told him enough to excite his
curiosity, and he knew the Americans would not aimlessly take up the
precious time of the general. "Our valiant commander is tired after a
strenuous day; but never is he too weary to attend to duty; and he
already finds himself interested in everything you brave young airmen
attempt. So please accompany me to headquarters."

Shortly afterwards the boys found themselves face to face with General
Petain.




CHAPTER IV

PRAISE FROM THE GENERAL


General Petain received the pair with his accustomed kindness. He loved
youth, and his eyes sparkled with pleasure as he gave each of them a
hand.

"My time is limited, I regret to say, my gallant Americans, or I should
gladly ask you all manner of questions concerning your own country. We
are all anxious to know when the great republic across the sea will
decide to cast her decisive influence into the scales to bring us the
victory we await with much patience. Tell me now what this strange thing
is you have come across to-day."

Tom waited for no second bidding. He realized how tired the general must
be after a strenuous day in keeping his finger on the pulse of the whole
front, where the fierce German attacks had been hurled without success.

Accordingly he started at once his tale of how they had been given a day
off for rest, and, having a love for hunting in their veins, had
borrowed an old shotgun and started forth. Without wasting any time in
useless descriptions he quickly reached the point where the pigeon was
shot.

Jack, having nothing to say just then, contented himself with watching
the various shades of expression that flitted across the face of the
commander. At mention of the pigeon his eyes sparkled, and he leaned
forward with an air of expectancy, as though anticipating what would
come next.

Then, as Tom produced the message written on the thin but tough paper
and handed it to the general the French officer eagerly scanned it. Jack
also noticed that he did not appear disappointed because he could not
immediately read the baffling communication. Of course it would be
written in some secret code; that was to be expected.

"It is fortunate," remarked the French officer, "that I have on my staff
one who is considered an expert at solving any and every species of
cipher code. He will speedily figure it all out for me, and then we
shall see what news this spy was transmitting to his commander. Please
continue your story, which is very interesting, and in which your part
does you both credit."

Tom, thus encouraged, went on. He told of their further search for the
mysterious man who had set the homing pigeon free after attaching the
secret message to it.

When he presently told of coming on the ruined farmhouse, and
discovering the ozier cage containing two additional pigeons, just where
the spy had left them in his hurried flight, the general fairly beamed.

"It is splendid news you have brought me--you aviators from our sister
republic across the sea," he remarked exultantly, as though already in
his fertile mind he could see great possibilities looming up whereby
those pigeons might be made to serve a purpose.

The story was soon finished. Tom, of course, thought it necessary to
tell of having been fired on while on their way back to the aviation
post, though no harm had resulted. He did this not for the purpose of
impressing the general with the idea that they had run any great
personal risk, but because it might have some influence on the plans the
officer probably had in mind.

After all had been told the commander again shook hands with both of the
air service boys. This indicated, as Tom well knew, that he had given
them all the time he could spare and that a dozen important things were
awaiting his attention, so he saluted and turned to depart.

"This may prove to be a most important thing you have discovered," the
general halted the aviators to say warmly. "The cipher will be solved,
and then, if the facts warrant it, we may have another written that can
be sent forward by one of your birds. You will give them over into the
charge of an officer whom I shall dispatch back with you to your
quarters. That will be convenient, I suppose?"

Tom hastened to assure him that they had expected just such a thing, and
had hoped that the two captured pigeons might prove the means of leading
the Crown Prince's forces into some sort of trap.

The general's black eyes snapped on hearing Tom say this.

"Ah! I see that you too have thought it out!" he exclaimed
enthusiastically. "Some day perhaps you may have command of an army, and
exercise that talent with glorious success. France thanks you."

Both boys were deeply moved by their brief interview with the busy
commander-in-chief of the French forces. They did not feel any
humiliation at being addressed as "my children," knowing that it was a
term of endearment used freely by officers high in command when
addressing, those in the ranks. In fact, the French army is very much
like a big family, the men loving those they serve under.

"Well, that job's over," remarked Jack, heaving a sigh of relief when
they were on their way to their quarters, accompanied by a jaunty
captain who, Tom believed, must be a member of the general's staff.

"I'm glad to have had such a fine opportunity for meeting General
Petain," Tom returned, for the captain at the time was walking a little
in the rear, conversing with a courier who had come running after him,
as if on important business.

"He was fine, wasn't he, Tom?"

"Next to Joffre I understand General Petain is the most beloved
commander the army has ever had," replied the other. "I'll always feel
proud that he shook hands so heartily with both of us."

The air service boys were soon in the automobile that had carried them
to the general's headquarters back of the French lines. Here the captain
joined them, having finished his hasty consultation with the courier. On
the ride to the aviation camp he chatted pleasantly with the young
Americans. He, it appeared, had spent several years attached to the
French Embassy at Washington.

He asked particularly concerning the feeling of the common people in
America, and what influence the powerful cliques of naturalized but
pro-German citizens were apt to have on the Government.

Tom was able to assure him that slowly but surely the people of free
America were becoming aroused to the deadly menace of German
imperialism, and that presently--it might come at any day, according to
the latest advices--Congress would assemble to hear a ringing appeal
from the President, urging them to declare war upon the Kaiser, war to
the finish.

Apparently what the boys said had much in it to comfort the French
captain. He knew only too well how eagerly his wearied nation was
listening to hear just such a message of hope. He knew, also, just what
it would mean for the brave defenders of France.

In due time the three arrived at the villa, Several of the American
pilots saw the trio leave the car, wondered much what was in the wind
that Tom and Jack should return with a member of General Petain's
personal staff. Their curiosity was considerably heightened when later
they saw the captain come out of the villa carrying a small ozier cage
containing two blue-rock carrier pigeons, and effusively shake hands
with both Tom and Jack, calling out to them as the car moved off:

"In the name of France and General Petain I thank you for what you have
done this day, my brave Americans!"

As the chums were about to pass into the building there was a hail.

"Wait a minute, Jack!" called one of their fellow pilots, hurrying up
with some object in his hand at which the two boys stared with rising
curiosity. "I've got something here for you!"

"For me?" cried the youth addressed. "I'm ever so much obliged, but it
strikes me I've got beyond the point of playing with a toy balloon;
though honestly now, when I was a kid I used to be pretty fond of
sailing one of 'em at the end of a long string, until it would get away,
and leave me staring up while it climbed toward the clouds."

"Oh, this one is about past doing any climbing, I should say," replied
the pilot, laughing at Jack's description of his childish woes. "In
fact, it's been out during the night, and the heavy air forced it to
come down. Listen, and I'll tell you a strange story that will make you
believe in fairy tales."

"Go on then, please," urged Jack. "You've got me all worked up already.
So there's a history attached to this little balloon, is there?"

"There was _something_ attached to it, something that may mean much
or little to you fellows," came the reply. "This thing was found by a
French dispatch bearer on his way across country. Out of curiosity he
stepped aside to look at the bobbing red object he had noticed among
some bushes in an open field. When he found that it had a paper fastened
to it, which on the outside had an address, he concluded to bring the
whole business along with him. He came here half an hour back inquiring
for Jack Parmly, and on finding you were away at the time left the
balloon and the paper in my charge. Take it, and see what the message
is, Jack!"




CHAPTER V

THE STRANGE WARNING


"Open it, Jack, and see what the message is," urged Tom, as his chum
stood with the scrap of damp paper held between his fingers, having
allowed the sagging little toy balloon to fall at his feet.

Jack was thinking just at that moment of the other message his companion
and he had found attached to the homing pigeon. But of course they could
not possibly have any sort of connection!

He opened the small bit of paper. It had some writing in lead pencil.
Once it had doubtless been plain enough, but the dampness must have
caused it to become faint. Still, Jack could make it out without much
difficulty. This was what he read aloud, so that Tom and the other pilot
could hear:

    "_Look carefully to your planes; examine every part. There is
    treachery in the air!_"

"That's all, fellows," said Jack, much puzzled, as he turned the paper
over and over, looking for some signature.

"No name attached, Jack?" asked his chum.

"Nothing whatever to tell who wrote that warning. Here, take a look at
it, Tom. Your eyes may be sharper than mine and see something I've
missed."

But Tom and the other pilot both failed to throw any light on the matter
after examining the paper thoroughly. They exchanged stares. Then Jack
laughed, a little queerly.

"This is certainly a mystery," he went on to say, trying to take the
thing as a joke. "Some kind friend sends me a solemn warning, and then
neglects to sign his name. Do you think any of the fellows of the
escadrille could be up to a prank?"

Tom shook his head. The other pilot also exhibited positive signs of
doubt in connection with such a thing.

"The boys often have their little jokes, and we are a merry bunch much
of the time, just to change off from the nervous strain we're living
under," the man observed. "But I'm sure not one of them would dream of
doing a thing like this. It would be a mean trick."

"Then both of you are inclined to believe this warning was meant in all
seriousness, are you?" continued Jack, no longer grinning as before.

"Yes, I do," Tom instantly announced. "It seems a bit childish, sending
it in such a queer fashion; but then perhaps it was the only way open to
the person. There was one chance in ten that it would be found; but you
know sometimes we can't choose our way of doing things, but must
accommodate ourselves to circumstances. This toy balloon being handy
suggested a possible way of getting the warning to you, Jack."

"But why me any more than you, Tom, or any other fellow in the
escadrille?" continued Jack, sorely bewildered.

"That's something we can only guess at," he was told. "Evidently this
person had your name, and knew you were working here with the Lafayette
boys. Try to think of some one you may have done something for to make
him feel grateful to you. Could it have been that boyish-looking German
prisoner we talked with the other day, and for whom you bound up a badly
damaged arm, Jack?"

"Oh! that boy!" exclaimed the other, and then shook his head. "No, it's
impossible. You see the poor chap could hardly talk halfway decent
English, and I'm sure he never could write my name like this. Besides,
Tom," Jack went on triumphantly, "I never bothered to mention to him
that I had a name. To him I was simply an American flying for France."

"Anybody else you can think of?" persisted Tom, for it seemed to him
that it meant considerable to try to discover who had sent the message
by such a strange channel.

Jack pondered. Then all at once he looked up with a light in his eyes.

"You've thought of something!" exclaimed the other pilot eagerly.

"Well, it might be possible, although I hardly believe she'd be the one
to go to such trouble. Still, she had children, she told me, at her home
in Lorraine, back of Metz; and this is a child's toy, this little
hot-air balloon."

"Do you mean that woman you assisted a week or so ago? Mrs. Neumann?"
asked Tom, quickly.

"Yes, it was only a little thing I was able to do for her, but she
seemed grateful, and said she hoped some day to be in a position to
repay the favor. Then later on I learned she had secured permission to
cross over to the German lines, in order to get to her family. She is a
widow with six children, you know, a native of Lorraine, and caught by
accident in one of the sudden furious rushes of the French, so that she
had been carried back with them when they retreated. At the time she had
been serving as a Red Cross nurse among the Germans. It was on that
account the French allowed her to return to her family. They are very
courteous, these French."

Tom was listening. He nodded his head as though it seemed promising at
least.

"Let's figure it out," he mused. "Which way was the wind coming from
last night, do either of you happen to know?"

"Almost from the north," the other aviator instantly responded. "I
chanced to notice that fact, for other reasons. But then it was almost
still, so the little balloon could not have drifted many miles before
the heavy atmosphere dragged it down until finally it landed in the
field."

"Well, that settles one thing," asserted Tom. "It came from back of the
German lines, don't you see?"

"Yes, that seems probable," admitted Jack.

"Your unknown friend was there at the time," continued Tom, in his
lawyer-like way, following up the trail he had started; "and hence
apparently in a position to know that some sort of plot was being
engineered against one Jack Parmly. Don't ask me why _you_ should
be selected for any rank treachery, because I don't know."

"And this person, this unknown friend of mine," Jack added, "wishing to
warn me so that I might not meet a bad end to-day, sent out this message
in the hope that it might fall back of our lines and be picked up. Tom,
it makes me have a queer feeling. I almost think I must be asleep and
dreaming."

"No, it's real enough. We may never know who the writer of this note is;
but we can heed the warning just the same, and go over to examine our
planes minutely. Whoever it was, spelled your name correctly. I've
studied the writing, but it seems to be assumed, and clumsy. There was a
reason for that too, as well as the writer failing to sign a name."

"What sort of reason?" queried Jack.

"Fear that in some way the message, and the balloon, might fall into
German hands and lead to unpleasant results," Tom continued. "We know
about how those Huns would serve any one who tried to spoil their plans.
They believe in frightfulness every time, and it might mean death to the
writer. This she evidently knew full well."

"Just why do you say 'she' when you speak of the writer?"

"Oh, I have an idea that Mrs. Neumann may be the mysterious friend who
is taking such desperate chances to send you a warning. Anyway,
something about it seems to say it isn't a man's handwriting. Besides,
neither of you may have noticed it, but there's a faint odor, as of
perfume, adheres to that bit of paper, though the dampness has taken it
almost all out."

Jack looked astonished at such shrewd reasoning.

"Well, you are certainly a wonder at seeing through things, Tom," he
hastened to say. "And so of course that settles it in my mind. Mrs.
Neumann sent this message to me; though how she could have learned that
there was anything treacherous going on beats my powers of reasoning."

"But don't you think it would pay to learn if there's any truth about it
all?" asked the other pilot, whose curiosity had been stirred up by such
a strange happening.

"Yes, let's all go over to the hangars and have the planes out for a
regular inspection," said Tom. "If mischief has been done the chances
are it would be in a part not usually examined by the mechanician before
a flight. Then again the damage, if there is any, might be so covered up
by the shrewd schemer that it would not be noticeable."

There were always cars going to and fro, for pilots came and went from
time to time; so the trio quickly found themselves being whirled along
over the road so often traveled in their daily work.

"How about that fellow they chased late yesterday afternoon, who was
loitering about the hangars and acting in a suspicious way?" asked the
friendly pilot, as they rode along. "More than a few of the fellows say
he must have been a spy, and up to some mischief, because he slipped off
so slickly."

"I had him in mind all the while," said Tom. "And if any mischief has
been done, of course we can lay it at his door; though just how he
managed to work we'll perhaps never know."

"I caught sight of him, too," Jack remarked; "and I only wish now I'd
had a good look at the chap who owned those pigeons to-day, so as to
tell if they were one and the same, which I believe to be a fact."

Just then Tom gave his chum a kick with the toe of his shoe. This
suddenly reminded Jack that he was treading on forbidden ground, since
they had resolved not to say anything to a third person concerning the
adventure of that afternoon.

The other member of the escadrille was looking interested. He understood
that Tom and Jack must have met with some singular adventure; but since
they did not see fit to take him into their confidence he was too polite
to ask questions, feeling there must be a good reason for their silence.

Presently they arrived at the hangars. It was now almost sunset. The
fliers were coming down one by one, their labor for the day having been
accomplished. It had been a pretty arduous day, too, and two members of
the escadrille had new honors coming to them, since they had dropped
enemy planes in full view of tens of thousands of cheering spectators,
after thrilling combats high in the air.

One had also passed through an experience that few aviators can look
back to. He had started to drop rapidly when, at almost ten thousand
feet altitude, his motor was struck by a missile from a rival pilot's
gun. When halfway down, either through a freak of fortune or some
wonderfully clever manipulation on the part of the pilot, the machine
righted, and he was enabled to volplane to safety, though considerably
bruised and cut up through hasty landing.

Jack quickly had his little Nieuport out of the hangar, and the three
airmen began a minute inspection. For a short time nothing developed
that had a suspicious appearance. Jack, in fact, was beginning to
believe the warning might after all be in the nature of a fake, or else
the spy had not found a favorable chance to do his foul work before
being frightened off.

But presently Tom gave utterance to an exclamation.

"Found anything, Tom?" asked Jack eagerly.

"Yes. Come around here, both of you!"

When the others joined Tom he pointed to where an important wire stay
had been dextrously filed so that it must snap under a severe wrench or
strain, such as commonly comes when a pilot is far afield, and wishes to
execute a necessary whirl.

Jack shivered as he took in the meaning of that partly severed stay. If
it gave way while he was far above the earth it must spell his certain
doom!




CHAPTER VI

LOOKING BACKWARD


"Just see the fiendish cleverness of the fellow who filed that stay!"
Tom cried, as they all stared. "He filled the indentation his sharp file
made with a bit of wax or chewing-gum of the same general color. Why, no
one would ever have noticed the least thing wrong when making the
ordinary examination."

"Then how did you manage to find it, Tom?" asked Jack, breathing hard,
as he pictured to himself the narrow escape he had had.

"I suspected something of the kind might be done; so I ran my thumb-nail
down each wire stay," came the answer. "And it turned out just as I
thought."

"There may be still more places filed in the same way," suggested the
other pilot, looking as black as a thunder-cloud; because such an act
was in his mind the rankest sort of treachery, worthy of only the most
degraded man.

"We will find them if there are," replied Tom, resolutely. "And when
this thing is known I imagine there'll be a general overhauling of all
the machines on the aviation field. One thing is certain, Jack. You were
playing in great luck when you suggested that we ask for a day off and
then picked out this particular one."

Jack shrugged his shoulders as he replied:

"That's right, Tom."

Nothing could be done just then, with night coming on. Tom talked with
several of the attendants at the hangars, and left it to them to go to
work with the coming of morning. He even showed them how cunningly the
work had been carried out; so they might be on their guard against such
a trick from that time forward.

Then the three returned to the villa. Others of the members of the
escadrille were in the car with the trio, so the talk was general,
experiences of the day's happenings being narrated, all told in a
careless fashion, as if those young aviators considered all such risks
as part of the ordinary routine of business.

Later on the news concerning Jack's singular warning, and what came of
it went the rounds. He was asked to show the brief note many times; but
in answer to the questions that came pouring in upon him, Jack could not
say more than he had already said with regard to his suspicions
concerning the probable writer of the message.

That night Tom and Jack preferred the quiet of their own apartment to
the general sitting-room, where the tired pilots gathered to smoke,
talk, play games, sing, and give their opinions on every topic
imaginable, including scraps of news received in late letters from home
towns across the sea.

"Do you know, Tom," Jack said unexpectedly; "I'd give something to know
where Bessie Gleason is just at this time. It's strange how often I
think about that young girl. It's just as if something that people call
intuition told me she might be in serious trouble through that
hard-looking guardian of hers, Carl Potzfeldt."

Tom smiled.

Bessie Gleason was a very pretty and winsome girl of about twelve years
of age, with whom Jack in particular had been quite "chummy" on the
voyage across the Atlantic, and through the submarine zone, as related
in "Air Service Boys Flying for France." The last he had seen of her was
when she waved her hand to him when leaving the steamer at its English
port. Her stern guardian had contracted a violent dislike for Jack, so
that the two had latterly been compelled to meet only in secret for
little confidential chats.

"Oh, you've taken to imagining all sorts of terrible things in
connection with pretty Bessie and her cruel guardian. He claimed to be a
Swiss, or a native of Alsace-Lorraine, which was it, Jack?"

"Uh-huh," murmured Jack Parmly, his thoughts just then far away from Tom
and his question, though fixed on Carl Potzfeldt and his young ward.

Bessie Gleason was a little American girl, a child of moods, fairylike
in appearance and of a maturity of manner that invariably attracted
those with whom she came in contact.

Her mother had been lost at sea, and by Mrs. Gleason's will the girl and
her property were left in Potzfeldt's care. Mr. Potzfeldt was taking her
to Europe, and on the steamship she and Jack Parmly had been friends,
and as Potzfeldt's actions were suspicious and, moreover, the girl did
not seem happy with him Jack had been troubled about her.

"I'm afraid you think too much about Bessie and her troubles, Jack; and
get yourself worked up about things that may never happen to her," Tom
went on after a pause.

"I knew you'd say that, Tom," the other told him reproachfully. "But I'm
not blaming you for it. However, there are several things Bessie told me
that I haven't mentioned to you before; and they help to make me feel
anxious about her happiness. She's a queer girl, you know, and intensely
patriotic."

"Yes I noticed that, even if you did monopolize most of her time,"
chuckled Tom.

"How she does hate the Germans, though! And that's what will get her
into trouble I'm afraid, if she and her guardian have managed to get
through the lines in any way, and back to his home town, wherever that
may be."

"Why should she feel so bitter toward the Kaiser and his people, Jack?"

"I'll tell you. Her mother was drowned. She was aboard the
_Lusitania_, and was never seen after the sinking. Mr. Potzfeldt
was there too, it seems, but couldn't save Mrs. Gleason, he claims,
though he tried in every way to do so. She was a distant relative of
his, you remember."

"Then if Bessie knows about her mother's death," Tom went on to say, "I
don't wonder she feels that way toward everything German. I'd hate the
entire race if my mother had been murdered, as those women and children
were, when that torpedo was launched against the great passenger steamer
without any warning."

"She told me she felt heart-broken because she was far too young to do
anything to assist in the drive against the central empires. You see,
Bessie has great hopes of some day growing tall enough to become a war
nurse. She is deeply interested in the Red Cross; and Tom, would you
believe it, the midget practices regular United States Army standing
exercises in the hope of hastening her growth."

"I honor the little girl for her ambition," Tom said. "But I'm inclined
to think this war will be long past before she has grown to a suitable
size to enlist among the nurses of the Paris hospitals. And if that Carl
Potzfeldt entertains the sentiments we suspected him of, and is secretly
in sympathy with the Huns, although passing for a neutral, her task will
be rendered doubly hard."

"That's what makes me feel bad every time I get to thinking of Bessie.
If only we could chance to run across them again I'd like to engineer
some scheme by which she could be taken away from her guardian. For
instance, if only it could be proved that Potzfeldt was in the pay of
the German Government, don't you see he could be stood up against a
wall, and fixed; and then some one would be found able and willing to
take care of the girl."

Tom laughed again.

"How nicely you make your arrangements, Jack! Very pleasant outlook for
poor Mr. Potzfeldt, I should say. Why, you hustle him off this earth
just as if he didn't matter thirty cents."

"It isn't because I'm heartless," expostulated the other hurriedly. "But
I'm sure that dark-faced man is a bad egg. We suspected him of being
hand-in-glove with Adolph Tuessig, the man who stole your father's
invention, and who we knew was a hired German spy over in America. And
from little hints Bessie dropped once in a while I am certain he doesn't
treat her well."

"Still, we can't do the least thing about it, Jack. If fortune should
ever bring us in contact with that pair again, why then we could perhaps
think up some sort of scheme to help Bessie. Now, I've got something
important to tell you."

"Something the captain must have said when he was chatting with you in
the mess-room immediately after supper, I guess. At the time I thought
he might be asking you about our adventures of to-day, but then I
noticed that he was doing pretty much all the talking. What is on the
carpet for us now?"

"We're going to be given our chance at last, Jack!"

"Do you mean to fly with the fighting escadrille, and meet German pilots
in a life and death battle up among the clouds?" asked Jack, in a voice
that had a tinge of awe about it; for he had often dreamed of such
honors coming to him; but the realization still seemed afar off.

"That is what we are promised," his chum assured him. "Of course our
education is not yet complete; but we have shown such progress that, as
there is need of additional pilots able to meet the Fokker planes while
a raid is in progress, we are to be given a showing."

"I'll not sleep much to-night for thinking of it," declared Jack.




CHAPTER VII

THE GREAT DAY ARRIVES


By the time the pilots of the American escadrille began to assemble on
the field where the airplane hangars were clustered, (these being more
or less camouflaged by means of paint cleverly applied to represent the
earth), the news concerning the air service boys' narrow escape had
become generally known.

Great was the indignation expressed by all. Up to this time there had
appeared to be considerable honor exhibited among-the flying men on both
sides. In fact many curious little courtesies had been exchanged that
seemed to put the aviation service on a plane of its own.

One thing was certain. After that there would be no taking things for
granted. Each pilot meant to satisfy himself as best he could that his
plane was in perfect order before risking his life in the upper
currents.

Jack was besieged for a full account of the matter. He, being an
obliging person, gladly told everything he knew. Naturally the mystery
attached to the discovery of the message of warning tied to the poor
little partly collapsed child's balloon aroused considerable curiosity
and speculation among the aviators.

The way some of them pumped Jack made him laugh; but he assured them he
was just about as "deep in the mud as they were in the mire."

"I've told you all about the woman named Mrs. Neumann," he repeated for
the tenth time. "And she's the only one I can think of who would be apt
to care a cent whether Jack Parmly happened to be alive or dead. If
anybody can give a better guess I'd like to hear it."

They did considerable "guessing," but after all it became the consensus
of opinion that the grateful Mrs. Neumann was responsible. And so
finally they let it go at that; for the day had begun, and there was an
abundance of work to be accomplished before the sun set again.

"But this is certain," said one of the leading flyers of the escadrille,
seriously; "if the Boches mean to stop playing fair it's bound to
demoralize the service. Up to now there's been an unwritten set of rules
to the game, which both sides have lived up to. I shall hate to see them
discarded, and brutal methods put in their place."

Others were of the opinion that there might have been something personal
connected with the attempt to kill Jack, through that shabby trick. The
German spy might have had a private grievance against the youth, they
said, which he meant to pay off in his own dastardly way.

No matter which turned out to be the truth, it was not pleasant for Jack
to believe he had become an object of hatred to some mysterious prowler,
and that possibly other secret attempts on his life might be made from
time to time.

That day passed, and another followed. There did not seem to be much
stirring on either side of the line; but such a lull frequently proved
the precursor of some gigantic battle, for which the armies were
preparing.

Of course, when the wind and weather permitted, there was always plenty
of excitement among the airplane escadrilles. All manner of little
expeditions were organized and carried out.

Now it was an attempt to get above that string of "sausage" balloons
used for observation purposes only, so that a few well-dropped bombs
might play havoc among them.

As these were always defended by a force of fighting planes hovering
above, all primed to give battle on the slightest provocation, the
result of these forays was that a number of hotly-contested fights were
"pulled off" high in air.

One pilot brought down another enemy, and increased his score a peg,
always a matter of pride with a pilot of a fighting plane. And another
of the escadrille had the honor of getting above those observation
balloons before a couple of them could be hastily pulled down.

Two of his companions engaged the defending Teuton pilots, and fended
them off purposely, in order to permit the raid. The selected man
swooped down like a hawk, passed the Gotha guard, and managed to shoot
his bomb downward with unerring aim. One of the balloons was seen to
burst into flames, and the second must have met with a like fate, since
it was perilously near at the time, though the dense smoke obscured
everything.

All these things and more did Tom and Jack witness through their glasses
as those two days passed. Tom especially was waiting to have his wish
realized with as much calmness as he could summon.

"I think it will come to-night, Jack," he told his chum, on the second
afternoon, as they prepared to return to their lodgings.

"Then you believe there's some big move on tap, and that to-morrow a
battle will be commenced? And all for the possession of some old ruined
fort, perhaps, that is now only a mass of crumpled masonry and debris!"

"You mustn't forget, Jack, it is the famous name that counts with these
romantic Frenchmen. Douaumont and Vaux mean everything to them, even if
there is nothing but a great mound of stone, mortar and earth to tell
where each fort once stood."

"Yes, I suppose you're right, Tom; and then again I was forgetting that
the retaking of a prominent position which the Germans had captured
means a heartening of the whole army. I've heard them talking of
Mort-Homme, and Hill Three Hundred and Four, as if those were the most
precious bits of territory in all France."

"These are sometimes strategic points, you know, keys to a further
advance. But there comes the captain now, and he's got his eye on us, as
sure as you live!" ejaculated Tom, giving a little start, and turning a
shade paler than usual, owing to the excess of his emotions, and the
anticipation of hearing pleasant news.

The leader of the Lafayette Escadrille smiled as he drew near. He waited
until he could speak without being overheard, for it was not always wise
to shout aloud when dealing with matters in which the High Command had a
deep interest, such as a pending advance movement.

"It is to-morrow, Raymond," he said quietly, yet with a twinkle in his
eye.

He had taken a great liking to these daring lads who had already made
such strides toward the goal of becoming "aces" in time, granting that
they lived through the risky period of their apprenticeship.

"Both?" gasped Jack eagerly.

The head pilot shook his head in the negative.

"Sorry to disappoint you, Parmly, but you'll have to wait a bit longer,"
he announced, whereat the other's face fell again, though he gulped, and
tried to appear content. "There are several things you must correct
before you can expect to take such chances. We are short a fighting
pilot for to-morrow, and I thought it was time we gave Raymond his
initiation."

Then as he walked alongside the chums he entered into a minute
description of the duties that would devolve upon Tom in his first time
up to serve as a guardian to the heavier planes acting as "fire-control"
and scouts, or "eyes of the army."

"Of course you are only to butt in if we are outnumbered," the leader
explained in conclusion. "The experienced and able fliers must take care
of such of the enemy as venture to attack our big machines. Some of
these Boches will be their best men, with records of a dozen or two
machines to their credit. It would be little short of suicide to send a
novice up against them, you understand."

Tom was ambitious, and would of course be delighted to prove his metal
when opposed by a famous ous "ace;" whose name and reputation had long
made him a terror to the French and British airmen. Nevertheless he
recognized the wisdom of what the captain was telling him, and promised
to restrain his eagerness until given the prearranged signal that his
chance had come.

It made Tom feel proud to know he had won the good opinion of such a
brave man as the captain, as well as the friendship of those other
gallant souls composing the American squadron of aviators fighting for
France.

"Still," he said to Jack later on, when they were together in their room
getting into their ordinary street clothes, "it made me feel a bit cheap
when he spoke of my being pitted against just an _ordinary_ pilot,
some fresh hand as anxious as we are to achieve a reputation. At the
same time that's what we must seem to these veterans of scores of air
combats, all of whom have met with the most thrilling adventures again
and again."

Jack managed to hide his bitter disappointment. He realized that he
would never be in the same class as his more brilliant chum. Tom fitted
for becoming an expert in the line had chosen for his calling. On the
other hand Jack began to believe that he was a little too slow-witted
ever to make a shining success as a fighting aviator, where skill must
be backed by astonishing quickness of mind and body, as well as
_something else_ within the heart that is an inherited birthright.

"Anyhow," he consoled himself by saying, not aloud, but softly, "I can
be the pilot of a bombing machine, and perhaps in time they'll give me
charge of a plane used as fire-control during the battle. That is as far
up the pole as I ought to aspire to climb. These chaps in the Lafayette
are one and all picked men, the very cream of the entire service."




CHAPTER VIII

OVER THE ENEMY'S LINES


"I say, Tom, it looks like a poor day for flying I'm afraid," Jack
called out in the chill of the early dawn the next morning, he having
been the first to get out of bed and step over to the window of their
sleeping room.

It was of course in the villa placed at the disposal of the escadrille,
many miles back of the first line of trenches.

Tom, however, did not bother his head about the weather to any
appreciable extent.

"It's likely to turn out a fair day for work," he told his chum, in his
cheery way, as he followed Jack to the window. "You know that's happened
lots of times. So far we've been lucky enough not to get caught in a
storm while aloft. Yes, I can already see that there isn't going to be a
stiff breeze; and what would a sprinkle of rain amount to?"

"I suppose the thing has to be pulled off, no matter what the weather
is," mused Jack, as he proceeded to dress, since breakfast had been
ordered at an unusually early hour that morning.

"Well, the High Command has made all arrangements for a big time. You
know what that means, when tens of thousands of poilus have to be
transferred during the darkness of night, so that the enemy pilots can't
glimpse the movement and give warning? So, unless the skies fall, we are
bound to get busy this morning."

The air service boys were soon at the hangars, where an animated scene
was taking place. Any one could see that something unusual was about to
take place, because of the numbers of men rushing this way and that,
while motors were popping and machine-guns being tried out so as to be
certain they were in prime condition for service. Scores of
mechanicians, chauffeurs, observers, as well as other helpers, went
about their work of getting "ready for business."

The air fighters were dressed in their fur-lined union suits, with fur
overcoats, gloves, and caps; for they would soon be soaring to great
heights, where the atmosphere was almost Arctic in its intensity.

They were examining their automatic pistols, seeing that their airplane
compasses, speed indicators, special airplane clocks, mounted on wire
springs, and altitude barometers were in their proper places and in
working order. Their very lives might depend on a little thing, and no
one could afford to neglect even trifles.

Every few minutes one of the planes would roll over the surface of the
level ground in front of the long line of hangars. Then, when sufficient
momentum had been attained, it would commence to climb swiftly upward.
Soon the machine would get into spirals like a winding staircase, and
mount toward an altitude of perhaps four thousand feet, there to await
the coming of companion craft before heading toward the battleground,
far distant.

Jack squeezed the hand of his chum, and gave him one last look. There
was no need of words to tell the deep feelings that gripped his loyal
heart; indeed, Jack was utterly unable to utter a single sentence.

Then Tom was off.

He made the ascent with his customary brilliancy, which had won him the
admiration of the entire escadrille. The air seemed to be filled with
various types of planes. Some were already moving off toward the front,
from which came the roar of battle, showing that already the action had
begun by an intense bombardment of a portion of the German trenches
which the French longed to retake.

Tom spent some little time "knocking around" while awaiting the coming
of those members of the Lafayette Escadrille who were the last to leave
the ground.

What is twenty or even thirty miles to a pilot in a speedy Neiuport
capable of going two miles a minute when pressed? They could be over the
lines in a very brief time after leaving the aviation camp.

Tom looked at the scene below him, which was spread out like a gigantic
map. He never wearied of observing it when simply "loafing" up in the
air, as at present. The sun was fairly above the eastern horizon, though
clouds drifted along in scattered masses, and it was as yet impossible
to tell what the day might bring forth.

Then the last of the squadron arrived, and the signal was given to start
for the front. Away they went with a whirr and a roar, seven strong.
They overtook a number of clumsy two-seaters on the way, observation
planes, bombing machines, or it might be those included in the
"fire-control" units going to relieve some of their kind already doing
their appointed bit in the battle.

Tom looked far beyond. He could see great oceans of smoke arising that
told of innumerable high explosives bursting, and enormous guns being
discharged. Both sides seemed hard at work, though the French were
certainly sending ten shells to one that came from the forces of the
Crown Prince. This told plainly enough which army expected to do the
attacking that day.

And yet while all this wonderful panorama of war was spread beneath
them, the seven pilots moving onward in wild-geese formation, with the
captain at the head of the V, they heard nothing of the tumult raging.
In their muffled ears sounded only the loud whirr of the propellers, and
the deafening explosions of the engines. It was almost as noisy as a
boiler shop in full blast.

The fire-control planes were already sending back their signals, the
observer aboard intently following the course of each monster shell to
note exactly where it landed, and then communicating with the gunners,
so they might correct their faults and make each missile count.

German pilots were in the air also, sometimes in swarms. Theirs was the
task to attack these heavier machines and try to cripple or destroy
them.

Of course each one of these machines of the French "relage," or
fire-control, was armed with a quick-firing gun; and there was an
observer aboard, as well as a deft pilot. They carried such a large
assortment of material, consisting among other things of a complete
wireless outfit, that they had to be built with unusually large wings.

This makes them slow to answer to the call of the pilot; and when
attacked by the more nimble Fokkers they have a hard time to keep from
being shot down. That is why a number of the Nieuports with well known
"aces" in charge, must always be hovering over the fire controls, ready
to fly to their assistance in case they are attacked.

"Things are surely beginning to happen," murmured Tom. "The Boches seem
to be in an unusually fierce and aggressive humor on this particular
morning."

The youth was right in this. The Germans had been thrown out of numerous
hard-won positions lately, and this gave them cause for feeling bitterly
toward the French.

By the time the American unit reached the field of battle, several
furious combats had already taken place with disastrous results. Two of
the enemy machines had been sent down, one of them in flames, after the
pilot had fallen at his post, fairly riddled by the gunfire of the
Frenchman. A birdman had also paid the great debt on the side of
Petain's men. As the score was two against one there seemed no cause for
depression.

The Americans would not be kept out of the fight for long. No sooner
were three adventurous Teuton pilots seen climbing up to attack the big
fire control machine when Tom's companions dropped down from the
"ceiling" to engage them.

Tom watched everything as though photographing the thrilling happenings
on his brain forever. He had a greater interest in these things than at
any previous period of his life, for was he not also hovering over that
observation Caudron, upon which the movements of the advancing French
troops depended? At any minute might he not receive the signal from the
captain to attack some fresh Boche, who had climbed high above the
battle lines to join the general scrimmage, or else "get" the big French
machine while its defenders had their hands full with his comrades?

Had Tom been able to use his binoculars just then, which was out of the
question of course, and look back to where the monster French guns were
firing, he might have noticed various white sheets spread out in
fantastic patterns on the ground, the picture varying every little
while.

These were used to "talk" with the observer who was sending those
messages from the fire-control plane, telling the gunners just how many
metres their fire was short, long, to the right, or to the left of their
intended objective.

Then again information was being sent by another observer to the
advancing infantry, warning them of perils that lay in their way, which
might have cost them great and grievous losses if they remained unknown
until the German trap was sprung.

The morning was advancing. Tom had seen his comrades chase off several
flocks of enemy aircraft that endeavored to interrupt the deadly work of
the observers. As yet his anticipated chance had not come. He was
beginning to feel impatient. Could it be that he must stay there almost
up among the clouds, and only be a "looker-on?"

How eagerly did his heart throb with renewed hope each time he
discovered signs of another attempt on the part of the enemy pilots to
engineer a raid that might check this observation work. They knew what
it was doing to advance the cause of the battling French; and that, as
often proved to be the case, the airplanes were again the "vigilant eyes
of the army."

It was well along in the morning when Tom Raymond's time came. The
fighting below had been going on for some time, and from fugitive
glimpses Tom snatched every now and then as he looked down, he had
reason to believe things were moving successfully for the assailants. At
least the French troops occupied a long line of trenches where the
Boches had been in possession at the close of the previous day.

Yes, there was another burst of ambitious fliers rising to take a
chance. The fact that already seven of their men had been dropped,
several with their planes ablaze, did not deter them; for those German
airmen had often proved their courage and were known as stubborn
fighters.

Soon another battle below the clouds was in progress. Besides Tom, there
were now only three of the Americans in the air, the remainder having
been driven down, some in trouble of some kind, others to replenish
their supplies. And there were _four_ enemy planes, Tom noticed,
even as he watched the machine of the captain and received the signal to
attack the latest arrival in the enemy squadron.




CHAPTER IX

WINNING HIS SPURS


"At last!"

Those were the expressive words that broke from Tom Raymond's lips when
he saw the commander give him the long-anticipated signal. Tom had
already discovered his intended antagonist. A fourth plane was coming up
quickly. It had held back to await the chance that would be offered when
the three defenders of the fire-control machine were hotly engaged with
the trio of skillful Boche pilots.

The game was very apparent. It was likewise exceedingly old. The French
commander was too experienced an aviator to be so easily caught. That
was why he had signaled to Tom to take care of the fourth and last
German airman, and guard the important observation plane.

Tom started down with a rush, just as a hungry hawk might swoop upon a
pigeon it had marked for its intended prey.

"I've got to make good!" the young aviator told himself. "I've got to
make good!"

The German pilot saw him coming. He had more than half expected to be
interfered with in his designs; but it would please him first of all to
riddle this ambitious young airman, and his Nieuport, and then to
accomplish his main purpose.

Now the two were so close that Tom could plainly see the black Maltese
crosses on the wings of the Teuton plane as it tilted in climbing.
Already had the other opened fire on him, for as his motor was silent
during his first long dive Tom could catch the tut-tut-tut of the
rapidly exploding mitrailleuse.

Somehow this did not unnerve him in the least, as he had feared it
might. Even when he realized that the missiles were cutting holes
through the wings a few feet away he did not grow uneasy. The spirit of
battle had gripped Tom. He was now attaining what had seemed to be the
height of his ambition. He was trying out his mettle against one of the
enemy pilots, a man with considerable more experience than himself, and
therefore well fitted to spur him on to do his level best.

He could see the pilot crouched in his place, and working his gun with
one hand while he managed some controls of his fleeting machine with the
other, for there was only one man aboard, though German machines usually
hold two. Long practice had made him an adept at this sort of thing, it
seemed.

But then Tom had been taught the same clever trick down at the French
school of aviation at Pau, and over on the lake at Casso. He was now
about to show whether he had learned his lesson to advantage. It was
French ways pitted against those of the German school.

Tom tried to aim directly at the foeman as he rushed toward him. Then he
pressed the release hard, and instantly the rapid-fire gun commenced its
staccato barking, as it spit out the bullets.

Crack! crack! crack! crack!

Thus the two rivals, rushing at each other like opposing birds of
enormous size, passed and dived, as though ducking to avoid the hot
fire. Tom looked back, hoping to discover the enemy winged and dropping
out of the fight. Nothing of the kind occurred; but on the contrary his
antagonist was sailing on, apparently untouched, at least in any vital
point.

That meant it must all be tried over again. The second round in the air
duel was about to open. It was impossible to predict what the outcome
might be, but at any rate Tom felt renewed courage and confidence.

If he had passed through one siege unscathed he believed he could show
considerable improvement the next time. Already had he learned how he
might avoid several little errors of judgment, not much in themselves
possibly; but which tended to interfere with his doing the one thing
necessary--firing point blank into the muffled face of the German pilot.

Once more were they rushing headlong toward each other. Tom was steadier
now, and more alert. He had his plan of campaign mapped out clearly in
his mind. He had moreover noticed a weak point about the other's method
of attack, of which he intended to take advantage.

The other three Americans were just as hotly engaged not far away; but
it was a case of every man for himself. Tom counted on receiving no
assistance. Indeed, while that feeling of confidence pulsed through his
veins he would have scorned to call for help, or even to allow it, if he
could prevent such a thing.

Again the guns opened fire as the two foes advanced with savage fury.
Such a battle in the clouds is on a plane that almost beggars
description. Nothing resembling it has ever been known before in all the
annals of history until the present world war broke out, and the
airplane was perfected as it stands to-day.

This attack was even more tumultuous than the first had been. The planes
tried dodging, and several tricks were brought to bear on either side;
for it seems that every pilot has his pet theories as to how best to
catch an opponent napping. Everything is fair, once the battle royal has
started and German wit is matched against American, or French.

Again did they pass each other for a sudden dip. Each feared to be
caught in a condition that would not permit of defense. They looked for
all the world like a couple of agile boxers engaged in a contest, in
which foot-work counted almost as much as that of the fists.

Around and around they flew, coming back to the attack a third, and even
a fourth time. Tom was beginning to grow impatient. Try as he could, he
did not seem able to bring the other down, though he was almost sure he
had poked his rapid-fire gun straight for the German's face, and when
only a comparatively short distance away.

"I've got to get him!" he muttered. "Or else he'll get me!"

He wondered whether there could be anything in what he had heard one old
aviator say, to the effect that he firmly believed some of those Germans
must be wearing armor or suits of mail, since he had poured streams of
missiles straight at them, and without the least appreciable effect.

The German was getting a bit reckless. No doubt he had anticipated an
easy victory over the other, whom he must have guessed was something of
a beginner at this sort of aerial combat. Tom's agility in avoiding
punishment annoyed him; likewise the way the bullets splashed around him
had a disconcerting effect on his mind.

This was the fifth dash, and it seemed as though the time had come when
one or the other should win the contest. They were growing more and more
desperate now; the fire of the battle had gone to their heads, and each
must have made up his mind to finish the fight then and there, judging
from the way they headed straight toward one another. At any rate Tom
had determined that he must win, and win without delay.

Bang!

Tom realized suddenly that he had been struck, for he felt a sudden
acute twinge. He neither knew nor cared how serious the injury might be,
so long as it did not incapacitate him from serving his machine. And,
best of all, thus far no missile from that popping mitrailleuse of the
German had done serious damage to the vitals of his plane.

Let the bullets cut holes all they pleased through the linen of the
wings; there would be no splitting, as happens in the case of cotton or
other fabrics; and such tiny apertures do not count for much in
retarding the upholding power of a plane.

Another dash, and this time Tom felt absolutely certain he had made a
hit. It seemed to him he must have fairly riddled the other pilot, so
close was he when he poured all that torrent of lead aboard his craft.

They rushed past one another, but Tom took the earliest possible
opportunity to redress, and look back at his foe. A thrill ran through
his entire being as he discovered that the other was in trouble. The
Fokker was descending in erratic spirals, evidently out of control. Man
or machine, perhaps both, had come within the deadly line of fire, and
the fight was over.

Turning, Tom watched the enemy plane go down. He had a queer, choking
sensation in his throat. Every novice probably feels that when he
watches his first rival heading earthward, with a mile or more to fall
before he strikes. Still, Tom grimly held his feelings in check. A
successful air pilot, especially when he manages a fighting craft, can
not let sentiment get the better of his combative spirit. It is a fair
test of skill and endurance, and as a rule the better man wins the game.
And war must always be an exhibition of cruelty in that human lives are
the stake played for.

Nevertheless Tom was secretly glad to discover that the plane was being
fairly well guided to earth, showing that the German pilot, though he
had lost his fight, could not have been killed outright, or even
mortally wounded.

Tom now found a chance to look around, and note what was going on. It
was just then that one of the leading American aviators drove at his
antagonist in a series of zigzag spins that must have bewildered the
German, he never having run up against such tactics before.

The consequence was the enemy met defeat. Tom knew what was going to
happen as soon as he saw the chief star of the Lafayette Escadrille
start his favorite attack. And ten seconds afterwards a second Teuton
plane was whirling around aimlessly and falling. It turned in its flight
so that its white belly showed plainly just as a fish will in its death
throes.

But the pilot was game to the finish, and managed in some wonderful
fashion to swing his damaged craft around again, so that when it landed
with a crash it fell bottom-down, and the motor did not come on top of
him.

Later on Tom learned that the man was badly injured, and made a
prisoner. Eventually he pulled through, though it was reported he would
never be fit for flying again, even if he gained his freedom.

The other two Germans had retreated, deeming the Americans too strong
for them. And Tom hoped it would be some time before others could muster
up sufficient courage to go aloft, to pit their machines with those of
the members of the Lafayette Escadrille.




CHAPTER X

AFTER THE BATTLE


During all this turmoil the fire-control plane pilot had kept his
machine at work. While the fighting guard engaged the German, the
observer aboard the larger craft continued to send his signals to the
batteries far in the rear of the French advanced lines; and through the
successful working of the undertaking a number of heavy Teuton guns had
already been silenced.

Tom now found time to look down, using his glasses for the purpose,
since the air in their immediate vicinity was clear of enemy planes. He
could see something of the battle, though so much smoke lay above the
battleground that it was only when this lifted temporarily that an
occasional fugitive glimpse could be obtained of the earth.

The French were undoubtedly pushing the Germans well out of their
advance trenches. They had already gone forward far enough to redeem a
fairly wide stretch of territory that had been taken from them at the
time the forces of the Crown Prince made their forward drive, at the
cost of more than a hundred thousand men.

Tom now felt another twinge in his shoulder. On looking into the matter
he discovered, as he suspected, that he had been wounded. Blood was
showing on his thick fur-lined coat.

Just then a plane approached him. Tom recognized the mark on the side,
and knew the muffled figure seated in the machine was the commander of
the escadrille. He was coming to ascertain whether the novice had drawn
out of his first combat entirely unscathed.

He had, in truth, cast many an anxious, fleeting look toward the pair
while Tom was "doing his bit" for France; for after discovering that the
German was an experienced pilot, and a man to be feared, the captain
would gladly have flown to the relief of Tom only that he had his hands
full with the Teuton he had attacked.

He made motions as he approached at reduced speed. Tom could not hear a
sound save the loud beat of his own motor, but he knew what the other
was asking.

So he touched his left shoulder with his finger, and held that up to
show that it was reddened. Then the Captain made a quick motion that was
meant for a command. Tom was to go down. There was no necessity for his
remaining aloft longer, now that another had arrived to relieve him from
the post of duty. He ought to call it a day's work, and have his
shoulder attended to.

Regretfully Tom obeyed. His fighting spirit was aroused, and he would
gladly have accepted a second challenge to combat, had the opportunity
come. He nodded his head to show he understood, and then started back
toward the French lines.

All this time shrapnel had been bursting here, there and everywhere
underneath them; but no one paid much attention to the shower. Indeed,
shrapnel does not account for as many hostile planes as might be
imagined; since each looks like a fly when ten thousand feet high, and
the surrounding space is so vast.

So Tom swung past the advance French lines, just as they were making
another forward movement. He could glimpse long lines of poilus
streaming over the shell-hole pitted terrain like ants in army array.
Tom would have been pleased to hover above them for a while, and watch
how those furious fighters rushed the Boches out of their second line
trenches, as though nothing could stay their push.

Beyond the French barrage fire was falling like a curtain. Tom could
tell this from the constant line of explosions that took place. The
Germans in the second trenches would have no chance of going back
through that deadly hailstorm of shells; they must either die at their
posts, or surrender, he saw.

So fifteen minutes later Tom dropped to the field, ran his plane up
close to the hangar, and then as a figure dashed wildly toward him,
started to climb wearily from his seat.

Of course it was Jack. He was wild with delight, and was swinging his
cap above his head with all the animation of a schoolboy.

"Oh! to think that I saw it all, Tom!" was what he cried, as he seized
the hand of his chum, and squeezed it fiercely, almost crying in his
excitement.

"You did!" exclaimed the other. "How did that happen, when I had the
glasses aloft with me?"

"Oh, I borrowed a pair from an obliging French officer. When he
understood that you were my chum, and that it was your first trial at
combat in the air, he gladly accommodated me. They are willing to do
almost anything for us Americans. My heart was up in my throat every
time you rushed at that terrible Boche pilot!"

"But how could you pick me out at that distance?" demanded Tom
incredulously, for it seemed almost unbelievable.

"I guessed that our captain would have you hold back when he and the
other two started to meet the rising Germans," said Jack. "You see, I
was wise enough to believe he would want you to butt in only in case a
fourth Boche came along. And when that happened I knew your chance had
come."

"It was pretty exciting while it lasted," remarked Tom grimly.

They were soon on the road to the villa, going in one of the cars used
to take the pilots when going to and returning from work. There was a
surgeon at hand, and an examination of Tom's hurt was made. It proved to
be a small matter, though it had bled quite freely.

"You must take a few days' rest, young M'sieu," the army surgeon told
the young aviator after he had dressed the wound. "It was a narrow
escape, I assure you. Three inches further down, and I would not like to
have answered for your life. But evidently France had further need of
your excellent services. I salute you, M'sieu Raymond, you have this day
done your duty well, and won your spurs."

The air service boys could not remain quietly at the villa while all
that furor was going on. They wished to be at the hangars, to greet
those who returned, and give the pilots who were sallying forth a last
word of encouragement.

It was a long day, and full of thrilling happenings. Other battles in
the air occurred along the extended front, and not all of them wound up
in victories for the Allied forces. Some distinguished Teuton "aces"
were flying on that occasion who would not be denied their toll. But the
Lafayette Escadrille lost none of its members, Tom and Jack were glad to
learn.

Night finally set its pall over the field where all day long the hostile
armies had fought and bled. The French were grimly holding their seized
terrain, and hurling the Germans back again and again. The serried ranks
had pushed forward up to within an hour of sunset; then, apparently
realizing that it was a hopeless task, the Teuton High Command had given
the order to withdraw.

On the following day the battle was not resumed. The French had their
hands full in strengthening and fortifying their new positions, while
the Germans must have been so severely punished and "shot to pieces"
that they needed time to effect the reorganization of their various
battalions and regiments.

So several days passed, and nothing out of the ordinary happened, at
least in connection with the two chums. Tom's slight wound was healing
fast, and he was told by the army surgeon that it would be quite safe
for him to go up again at any time now, a fact that pleased the young
aviator immensely.

"I'm going to make a record for myself," he told his chum.

"You're the fellow to do it," answered Jack. "Wish I was in your shoes."




CHAPTER XI

A SHOW ON THE FRONT


While the fighting on the Verdun front was furious at times, with
prolonged spasms when the Germans seemed determined to recover the
territory they had lost to the French, there were also periods of almost
total calm.

During these quiet periods the members of the American escadrille were
sometimes hard pushed for ways in which to pass the time away, and amuse
themselves. Inaction fretted most of them, since they were endowed with
that restless spirit which seems to be the inherent trait of most
Americans.

Many were the expedients tried by means of which some amusement might be
extracted from life. Their daily business was so exciting that these
slumps left the aviators nervous and unhappy. It was like the sailor
who, bowling along under full pressure of canvas for weeks, in the old
days of the sailing vessel, suddenly found himself in the "doldrums,"
and becalmed for what might be an indefinite period--it was apt to wear
upon a nervous system that demanded work.

Of course the pilots were merry while at meals and during their loafing
periods; but every time one of their number returned from the front and
reported the inaction as still continuing, many deep sighs of discontent
would arise.

Then a clever thought occurred to some one of the men. Perhaps it was
suggested by a happy-go-lucky Irish aviator who was connected with the
British air forces, and wore the marks of distinguished service on his
arm and cap.

Sergeant Barney McGee had received a month's furlough in order to
recover from injuries which he had sustained. Instead of going back to
Ireland to spend his enforced vacation, as one might naturally expect
him to do, McGee put in the time visiting other parts of the long front
between Ypres and Verdun.

After all, there was nothing so very singular about that. Give an old
railroad engineer a week off, and presently you will discover him
spending the time loafing around the roundhouse, chatting with the other
engineers, and investigating things. His whole life being wrapped up in
his work his idea of a vacation consists of being free to watch his
fellows of the same craft work.

Sergeant McGee was an exceedingly droll chap. He spent a couple of weeks
with a French cousin who was also an aviator, and in time came to know
the jolly members of the Lafayette Escadrille. He grew to be exceedingly
fond of them all, and was in the mess-room nearly every night.

His idea was that they should get up a show to pass these dull evenings
away. If the enemy allowed them sufficient time they could even give a
public performance, and give the proceeds to the Red Cross.

It took like wildfire with the Americans, casting about at the time for
some way to kill dull care, and make the hours pass more quickly until
called to action again.

A survey developed the fact that there were a number in and out of the
Lafayette Escadrille who possessed a talent of some kind or other. This
one had a violin which he loved to play; and, while not a finished
artist, he was able to make real and lovely music by means of his clever
bow. Another, it turned out, had a good tenor voice, and knew many of
the most popular songs of the day. A third showed a talent for mimicking
well known people, particularly Americans of national fame. Several
agreed to black up, and give a humorous little minstrel skit that they
declared would set the house in a roar.

It was Barney McGee himself who most astonished the Americans, however.
At the first rehearsal he appeared before their astonished eyes dressed
to imitate a well known and popular moving picture star and he carried
out the part in a fashion that caused the wildest excitement. From that
moment the success of the show was assured.

They made feverish preparations, for no one could tell just when the
period of inaction would come to an end, and every available member of
the several fraternizing escadrilles be ordered to rush to the front
again, to take his life in his hands, and risk it hourly for the great
cause.

Tom and Jack both had parts in the entertainment. Jack made a good
"bones" for the minstrels, and he coaxed his chum to don a burnt-cork
face for that one evening, and show what he could do as a comedian of
parts.

They found a building in Bar-le-Duc that could be used, and which would
hold a respectable sized audience. Little preparation was needed save to
build a stage and get seating arrangements. Where chairs were not
available benches had to take their place. Lights were also provided,
and what few accessories they needed, such as curtains and stage
scenery, were improvised after a fashion.

In the spirit of fun that prevailed "any old thing went," as Jack
expressed it. The makeshifts that came to light when the performers
appeared dressed for their various parts were many and startling. They
had borrowed or begged anything that promised to answer the purpose from
a long-tailed French coat to a lady's highly colored shawl. Wigs had
been sent for, and Paris had responded with an assortment that left
nothing to be desired.

The members of the two French air squadrons whose headquarters were near
by, had entered into the affair with great zest. They blessed the little
Irish pilot for his suggestion. And Sergeant Barney McGee was on the
jump all day long, displaying all the sterling traits that distinguish
able generals and leaders of men.

The time approached when the entertainment was to come off. The
performers were sure of a full house, provided no war orders were issued
that would interfere with the arrangements.

"Since Fritz has kept quiet for so many dreary days now," one pilot was
heard to say on the morning of the entertainment, "let us hope we'll
have just one more peaceful evening to reap the reward of all this
training. It would break the heart of Sergeant Barney if the order came
for every one to buckle down to hard work just when his big show is
about to come off."

The weather man proved friendly, for he gave them a splendid day, with
the promise of a moonlight night. Besides, the cold had pretty well
vanished, and it was really becoming more seasonable, with the sun
warming the earth, and the mud drying up to a considerable extent.

When the show opened that night it was to a house jammed to the doors.
Even the windows were utilized for seating room; and crowds stood
without, unable to gain admittance.

"Some crowd, eh?" remarked Jack, as he watched the airmen, soldiers and
others pouring in.

"I should say so!" cried Tom. "I hope we make good."

It was certainly a unique performance, considering the fact that it was
given in a camp close to the battle lines; and that at any hour every
one of those who were dressed so fancifully and conducted themselves as
actors born to the stage, might be called on to mount to the clouds, and
perform their dangerous work of fighting for France, perhaps even giving
up their lives.

Loud applause greeted every individual act. The violin music drew tears
from eyes unused to weeping, because the strains of "Way Down Upon the
Suwannee River," "Home, Sweet Home," and other loved airs tenderly and
beautifully played, as they were, carried the Americans back again to
those near and dear, those whom they might never again see on this
earth.

The songs were rapturously applauded, and the singers forced to give
encore after encore. One youth who played the part of a little maid from
school, and sang in a sweet soprano voice, caused the greatest
enthusiasm of the evening; but then everything seemed to make a decided
hit.

Tom and Jack, as members of the minstrel troupe, did their parts well,
though neither professed to be a star of the first magnitude. They
certainly enjoyed seeing and hearing the others go through with their
appointed tasks. As for Sergeant Barney McGee, he drew the house down
every time he appeared on the stage in his quaint dress, and with the
famous walk that is the trade-mark of the character whom he represented.

Two-thirds of the entire show was soon carried out. Indeed, the rest was
to be more or less a repetition of preceding acts, though the pleased
audience seemed eager to sit for another hour, and applaud each turn
vigorously and uproariously.

However, it was not fated that the evening should pass entirely without
some interruption. Afterwards the actors, and those who had enjoyed the
performance from in front, agreed that they had been exceedingly lucky
as it was, and that "half a loaf was much better than no bread at all."

Those whose turns were finished remained, of course, as part of the
audience. Some of the black-faced artists lingered in the so-called
"wings" to watch what was going on, desirous of getting all the fun
possible out of the evening.

It was not a case of "eat, drink, and be merry, for to-morrow we die;"
but "have all the happy times you can, fellows, while the going is good,
for to-morrow we fight."

Sergeant Barney McGee was on again, and the audience was convulsed with
laughter over his ludicrous antics. He appeared to be a born actor and
mimic; and had they not known otherwise Tom and Jack could have declared
that the comedian who was under contract with an American film company,
and doubtless in California making pictures at that moment, had been
suddenly transported to the French fighting front to entertain the
soldiers.

Suddenly the laughter came to a stop. The building in which the show was
being held shook as though a violent thunderclap had rocked the earth.
This loud detonation that broke upon their hearing, however, was only
too familiar to all those army aviators. They understood its dread
meaning.

The enemy had taken this opportunity to send over a squadron of raiding
Fokkers to bomb the hangars of the French and American fliers at
Bar-le-Duc!




CHAPTER XII

CLOWNS ON THE WING


Boom!

What followed that first heavy detonation was very much like a riot. The
audience became frantic under the belief that it meant an attack on the
town, and that the missiles would presently drop upon the roofs, working
destruction to everything around.

It was the actors, however, who were the most exercised. One and all
they understood what it meant to them. Their planes were in danger of
being demolished! In some way the Teutons must have learned about the
entertainment, and realized that almost every Allied pilot would want to
attend it. They rightly guessed that for once the guard about the
aviation field and numerous hangars where the dozens upon dozens of
planes of every description were housed when not in use, would be
unusually light. They had also taken advantage of the bright moonlight
to make a bold sally over the French lines and reach this distant point
undiscovered.

Boom! boom! boom!

Other crashing sounds announced that the enemy machines were busily at
work. Each pilot pictured the entire camp under bombardment, with the
utmost disaster overtaking the airplanes upon which General Petain was
depending so much to serve as the "eyes" of his brave army.

There was a general and maddened rush. Every one wanted to get to the
camp in the briefest possible space of time. There was no chance for the
actors to change their clothes. They were glad enough of an opportunity
to snatch up a heavy fur-lined coat, either their own or some other
person's. With this to hide their ludicrous attire, and also give some
needed warmth once they went aloft, they hastened to find a waiting car,
which, when loaded to its capacity, would be sent like mad along the
road to the aviation field.

It was one of the most amazing sights imaginable, to see those pilots,
many of whom were world famous, thus garbed. It looked as though some
asylum of freaks had opened its doors and allowed the inmates to escape
to the highways and byways.

Only one thought possessed them all, which was to get to the hangars in
the shortest possible time. When they arrived each anticipated seeking
his particular plane. If that chanced to be out of commission, then
commandeering any other, it mattered little whose, so long as they were
able to go up, and give battle to the audacious Teuton pilots who had
raided their camp at Bar-le-Duc.

"We've got to save our machines!" cried Tom. "Come on!"

"Right you are!" responded Jack.

Tom and Jack were with the rest who found some way to crowd aboard one
of the waiting cars that were seized upon to carry the pilots to the
field. As they went booming furiously along the road they could still
hear those frightful explosions ahead, each one accompanied by a flash
as of lightning. The reports were almost deafening.

Eager eyes were turned aloft. The moon shone, but it was difficult to
make out so small an object as an airplane at a height of a mile or more
without the use of searchlights, and even these were not very efficient
on such a night.

Still, some of the pilots believed they could see several enemy planes
swooping over at a lower level, possibly, they thought, on the lookout
for the procession of cars bearing the aroused Allied aviators to the
hangars.

Bang!

A bomb fell not fifty feet away from the car in which the two chums were
seated. One of their companions received a trifling wound from the
effect of the explosion of the TNT contents of the bomb, said to be the
most powerful known for such uses, and handled by the engineers of all
the armies, under different names.

If the design of the Boche who swooped down for the purpose of waylaying
the cars carrying the French and American airmen was to rob the Allies
of the services of a dozen eminent pilots all at once, it failed in
execution.

At last the aviators arrived on the scene. It was lively enough, with
bombs still bursting here and there. Already considerable damage had
been done to some of the hangars.

The Allied pilots were "mad all the way through" at having been caught
napping by the foe. They paid no attention to the danger that still hung
over their heads, with the enemy's supply of explosives as yet
unexhausted. While the dreadful detonations continued, sometimes
exceedingly close by, the various pilots seized upon such mechanicians
as they could.

One by one the planes rolled along the field and began to climb upward
by way of the usual spiral staircase route, to give battle to the enemy,
regardless of any superiority in numbers.

Jack was dismayed to discover that his plane was badly wrecked by one of
the explosions. Indeed, it was afterwards found that he had to have a
new machine, since the repairs necessary to put the old one into service
again were too complicated to be done at the front.

Tom was more fortunate. His hangar had also suffered to some extent, but
so far as could be seen in a hasty examination his plane was not injured
in the least.

He too went up, burnt-corked face and all. There were clowns abroad that
night who could give Tom many points in the game, so far as comical
looks went, and still easily win the stakes. But all else was forgotten
under the spur of the moment, save that each man was eager to get in
touch with the Boche pilots who had almost spoiled their one great
evening.

But no longer were those crashing detonations coming. This told the
story only too well. The Germans had either exhausted their supply of
bombs, or else they deemed discretion the better part of valor. They had
evidently taken their departure before the first Allied pilot got up to
the elevation they had been using in their bombardment.

Nothing could be seen of them, though had the Allied pilots been able to
use their ears, which was impossible when their own motors were making
such loud noises, they might have heard, in the distance and to the
east, the telltale music of Teuton propellers beating the air in a rush
for home ports.

A pursuit was organized, and several planes followed the retreating
invaders over the entire distance to the front; but it was of no avail.
The enemy planes had had too good a start, and were being pushed for all
they were worth to get beyond the danger zone.

There had been several accidents at the Bar-le-Duc field, but none of
them fatal. This was not at all surprising, considering the haste shown
by the pilots to mount and engage the foemen.

Too, several of the planes besides Jack's had been damaged, a
circumstance which brought about disaster before the aviator was able to
leave the ground.

As the fliers came back one after another, filled with indignation and
disappointed hopes, Jack stalked about, with his black face, yet laughed
to see what comical pictures most of his fellow aviators made.

By degrees most of them began to realize that the joke was on them, and
joined in greeting with noisy shouts each fresh arrival from above. The
damage had not been so very serious after all, since most of the Teuton
bombs had either failed to explode when aimed true, or else only dug
enormous craters in the ground where it did not matter, sometimes even a
quarter of a mile away from the hangars. Jack's machine, it was found,
was the only one badly damaged.

From that time there was one subject on which American and French pilots
were agreed. They must certainly repay their enemy rivals for this
visitation. The honors could not continue to be all on one side.

So from that hour every Allied pilot who went far back of the German
lines used his glasses diligently, in the endeavor to locate the secret
aviation field of the Boche. This would naturally be camouflaged in the
customary fashion, at which the Teutons had become almost as proficient
as the French; but trust an airman to spy out the lodging place of his
kind.

Step by step they learned which direction the enemy planes took in
coming to the front, and retiring when through for the day. Thus in good
time the hiding place was found. Great was the delight of the whole
Lafayette Escadrille when this confidential news was passed about. And,
later on, a party of Allied aviators paid a night visit to the German
camp, and dropped several tons of high explosives from bombing planes,
that were heavily guarded by the fighting Nieuports.

They had reason to believe from what they themselves saw, as well as
through a secret report received from a French spy, that their aim had
been remarkably fine; and that many times the amount of damage the
Germans had done at Bar-le-Duc had been carried out on the reprisal
sally.

After that it seemed as though the slate had been wiped clean. Their
honor had been fully purged of the stain that had rested on it ever
since that dreadful night when they were caught off their guard.

It turned out that the enemy had meant to start an action on the
following day, and it had been hoped that the squadron of airmen might
so cripple the French service that the advantage would be all on the
side of the assailants.

Something happened, however, to balk the plans of the Crown Prince.
Perhaps he had a reprimand from his august father and emperor for so
recklessly sacrificing such vast numbers of his men in a fruitless
assault against the stonewall defensive of the French army. It may also
have been something else that called the attack off, but at any rate it
failed of accomplishment.

The stagnation along the front continued; but all this while General
Petain was making quiet though effective preparations, in order some day
to strike a staggering blow, such as the French had before given, which
would take the enemy by surprise, and push him still further back.

Jack was fretting because thus far he had seen so little of real action.
Since his Nieuport had been sent away, and another had as yet failed to
arrive for his use, he often bewailed his ill-luck. He even assured his
chum the "green mould would be growing all over his person if something
didn't soon come to pass to break the terrible monotony."

But every lane, however long, must have its turning; and Jack's hour
struck at last.




CHAPTER XIII

MORE WORK IN PROSPECT


"Tom, sit down here on this bench, won't you? I want to have a little
talk with you about some things that have bothered me a whole lot
lately," said Jack, some days after the exciting experiences narrated in
the two preceding chapters.

"I can give a pretty good guess what they are, Jack, since I see you
staring hard at the slip of paper found attached to the toy balloon
which drifted over our lines from somewhere back of the German front."

"Yes; I own up I do sit and look at that paper, Tom. If it could only
talk I'd know who penned that warning, and my curiosity'd be satisfied
for one thing. But try as hard as I may, I can't be certain whether it
was Mrs. Neumann, or somebody else. But I wanted to speak to you about
Bessie just now."

"What about her, Jack?" asked Tom, knowing how much his chum was
concerned over the unknown fate of the pretty young girl they had met on
the Atlantic liner, and who was apparently anything but happy in the
charge of her legally appointed guardian, Carl Potzfeldt.

"There are several things she told me, half unwillingly, I admit, that I
guess I haven't said anything about to you, Tom."

"Then she confided her secrets to you, eh?" half chuckled Tom; though he
saw his chum was in anything but a humorous frame of mind. "I remember
you told me she felt very bitter toward all Germans because she had lost
her mother when the _Lusitania_ went down."

"Yes. But this had to do with her guardian," Jack continued.

"Oh, I see! Mr. Potzfeldt, Jack? You haven't felt favorably disposed
toward that gentleman at any time since first meeting him."

"Neither have you, Tom, to tell the truth!" declared the other quickly.
"In fact, as I remember it, both of us were pretty much inclined to
believe he was a paid spy of the German Government, working on some line
of dark business over in America. Well, he had to clear out in a hurry,
Bessie told me."

"Did the authorities get track of his scheming work, and was he in
danger of being arrested for plotting against Uncle Sam's interests as a
neutral?" Tom asked.

"It may have been that; but Bessie wasn't sure about it. In fact, she
seemed inclined to believe her guardian had some secret, which was in
danger of being exposed. An old friend of her mother's was interesting
himself in the matter. Given time, he might have made it uncomfortable
for Carl Potzfeldt; and so the gentleman cleared out between two days."

"Taking Bessie with him!"

"Yes. They made as if to go to Chicago, but instead hurried to New York.
When he came aboard at the last call he kept to his cabin for a time,
until we were well away from land. There has been considerable of
mystery about his actions. Bessie is afraid of him, too. She even hinted
that she believed he might have obtained control of her fortune and
herself through fraud, and that this was in danger of being found out at
the time he cut stick and ran."

"All this is interesting, Jack; but just when and how we're ever going
to learn the truth about it I'm unable even to guess. It would be like
hunting for a needle in a haystack to try to find Potzfeldt. He and his
pretty little ward may be hundreds of miles away from here."

"Perhaps you're right, Tom," mused the other sadly, as he stared afar
off toward the north. "I'd be glad of a chance to do something for that
poor girl. She is to be greatly pitied, if she's wholly in the power of
a man who wouldn't hesitate to do _anything_, if he saw a chance
for gain ahead."

"Well, all you can do, Jack, is to live on and hope a lucky chance will
bob up for you. But there's our captain beckoning to me. Perhaps another
battle is on the carpet for to-morrow, and I'll be given a look-in
again."

"Oh, if the lightning would only strike me too!" sighed Jack, enviously.
"Please beg him to figure out something I can do, Tom. If it's only
occupying a place aboard an observation plane or taking photographs of
the Germans regrouping far back of the lines, I'd gladly welcome it.
Anything but sitting here, when all the other pilots are at work."

Tom hurried to join the commander of the Lafayette Escadrille. He had
taken a great fancy to the gallant man, and believed this feeling was in
a measure returned. Jack continued to sit and mope. He really felt
slighted to be left out when so much thrilling work was being done.

He had put away the well-thumbed scrap of paper with its mysterious
lines of warning, for the time being Bessie and all her troubles passing
from his mind. Jack was now full of his own affairs. He found himself
growing a bit discontented because thus far he had been allowed to do so
little for the cause, when his heart was full to overflowing with a
desire to assist.

There were aviators going and coming all the time, and surely many of
them did not excel him appreciably in talents. Why did not those in
charge find something for an ambitious pilot to do? He was striving
daily to master the weak spots in his education; and had not the captain
himself assured him he was doing bravely? He turned to cast an
occasional look toward the spot where Tom and the commander of the air
squadron still talked earnestly. Yes, something was certainly "on tap,"
as Jack expressed it, for he saw the other carefully examining a bit of
paper his companion had evidently placed in his hand.

Jack began to be interested. Perhaps after all it might turn out to be
something quite different from what Tom had anticipated. Had the captain
simply wished to notify the other to be ready to answer a call on the
following morning, surely he need not have taken all this time; nor
would he have given Tom that paper, undoubtedly carrying explicit
instructions.

How the minutes dragged! Jack thought it an eternity before he saw Tom
and the captain separate. He was glad to notice that his chum once more
headed in the direction of the spot where they had been seated on a
bench back of the long row of frame buildings used for permanent hangars
at the Bar-le-Duc aviation field.

Yes, Tom had evidently been told something that pleased him very much.
His smile admitted the fact, and Jack knew by now just how to read the
face of his comrade so as to get a good idea of what was passing in his
mind.

"Looks like good news, Tom," he cried out, for motors were rattling and
throbbing, mechanicians and helpers, as well as pilots, calling to one
another, and all manner of sounds combining to make a great racket.

Tom shrugged his shoulders in a non-committal way, which might mean a
whole lot, and again might express a small fraction of disappointment.

"Yes, I've been given a job, if that's what you mean," he admitted, as
he dropped down once more on the bench alongside Jack, and threw one leg
over the other.

"More fighting to-morrow, possibly?" queried Jack, anxiously. But he
found his curiosity further whetted when Tom shook his head in the
negative.

"Not necessarily this time, it seems," he went on to say; "though of
course you never can tell what you'll strike when once you pass fifty
miles, more or less, behind the enemy front."

Jack pursed his lips up as if about to whistle, but he made no sound. It
was only a visible indication of surprise on his part--surprise, and an
eager desire to know just what his chum was so slow in telling him.

"Another bombing raid, then, is it?"

"Never a bomb going along this time," came the puzzling answer. "Nor is
there going to be a big bunch of planes starting out. I'm to be the only
pilot in the game this time, Jack."

"You're knocking me silly with that, Tom," protested the other young
aviator. "I can see the twinkle in your eyes, as if you were holding
something back, so as to tantalize me. Are you free to tell me what this
business of yours it is the captain has just handed over to you?"

"Oh, surely, Jack. He told me I could take _one_ fellow into my
confidence, and no more. So I mean to tell you all about it."

Tom turned and cast a careful look around. They were not very close to
any of the hangars, it happened; and none of the many helpers and
attendants could possibly overhear what was said, with all that clatter
constantly going on.

"I guess it's perfectly safe for me to talk here, Jack, and not give the
thing away. You know it does seem that the German spies are able to
penetrate nearly everywhere, and pick up all sorts of valuable
information, to send across the line in any one of a dozen different
ways."

"Yes. But go on, Tom."

"It seems there is need of some one to go to-night to a particular place
far back of the German lines--in fact, close to the fortified city of
Metz itself. In a certain place, inside a hollow post, will be found a
paper marked in cipher, and containing much valuable information which
has been collected by one of the ablest of the French spies. He is
really a native of Alsace-Lorraine, and well thought of by the Germans.
As it is utterly out of the question for him to report in person, he has
adopted this way of getting his news to General Petain. And as there is
a scarcity of pilots capable of doing this work our captain has selected
me to undertake it for the cause."

"But Tom, I should have thought he would have picked out some one more
familiar with the ground back there. How can you find your way to that
particular place, if you've never been there before?"

"I've been given directions that are bound to take me right," Tom
assured his worried chum. "There was a man they used for this purpose,
and several times he's brought back the papers; but on his last trip he
had the misfortune to run into a bunch of cruising Fokkers, and they
brought him down. He fell fortunately inside the French lines, so his
papers were saved; but Francois will never handle the controls of a
plane again. He was killed."

"Then there is danger in the game!"

"Certainly there is. But in these times who could dream of passing so
far back of the German front without expecting to be in constant peril?
The papers will be put in a little box previously prepared. Should
disaster overtake us, it will be flung overboard, and before it reaches
the ground everything will have been consumed by the fire that follows."

Jack's eyes began to glitter.

"Just so, Tom! But I notice that you used the plural pronoun when you
spoke. Then you do not go on this mission alone?"

"No, that's right. I have been given permission to pick out my one
companion, for there will be two of us aboard the plane to-night."

Jack tried to keep calm, but it was indeed difficult, and his voice
faltered more or less as he hurriedly went on to say:

"Have you already made your selection?"

"Yes," the other assured him in his tantalizing way. "I wanted to know
whether the captain approved of my choice; which I am glad to say turned
out to be the case."

Jack gulped something down, and then blurted out:

"Did you mention my name at all, Tom?"

"Yours was the only one I had in mind; and Jack, rest easy, you're going
along with me to-night to glimpse the lights of Metz!"




CHAPTER XIV

OFF ON A DARING MISSION


The two air service boys fell to talking earnestly concerning what they
should take with them, and how to study a map which their captain had
promised to put in Tom's hands immediately.

This was not of the ordinary kind, but so definitely marked for just
such an emergency that even a novice could probably find his way to
Metz, granting that he possessed the necessary qualifications of an air
pilot.

Presently a messenger came with a package for Tom. This proved to be the
chart from the commander of the air squadron. Tom was to make as good a
copy as was in his power, for the original was too valuable to risk
losing.

Jack understood that there were several reasons for having Tom do this.
In the first place his work on the chart would familiarize the young
aviator with its every detail, and fix things firmly in his mind. Then
again, if they were lost, and never returned, the priceless chart for
night voyaging over the enemy's lines would be at least safe.

Daring men had gone forth on similar desperate errands before then, and
had never been heard from again. It is the fortune of war. Those who
indulge in enterprises that border on the sensational must always expect
to sup with deadly peril.

When the evening meal was announced the two chums were already deep in
the work. Of course not a whisper of their intended mission was breathed
at the table. No one dreamed of their contemplated trip. The customary
chatter and good-natured badinage flowed during the whole supper-time.
While some of the American aviators had received wounds in recent
engagements there had been no chair vacant for some little time now; and
hence no gloom rested on the escadrille. From the table the boys again
went to their room.

"How far is Metz from Verdun?" asked Jack, as they labored to complete
their preparations for departure.

"Not over forty miles, I should say, as the crow flies, Jack. I've never
been over the route, but it can be measured on this copy of the map."

"And that's the direct line we expect to cover, of course?"

"We'll head due east."

"And as it'll be densely dark when we start I guess we needn't mount to
ten thousand feet to pass over the enemy lines, eh, Tom?"

"There'll really be little need," came the reply, showing that the pilot
had already figured all this out. "At the same time we ought to keep far
enough out of range to avoid being struck by stray shrapnel."

"Will they bombard us, do you think?" demanded Jack.

"Oh, that's to be expected," said Tom indifferently. "You see the men
who man the anti-aircraft guns are constantly on the alert. They're
bound to hear the whirr of our propeller as we pass over, no matter how
high we soar. The searchlight will spot us out, and then they'll do
their best to make things uncomfortable for the pair of us. But the
chances are ten thousand to one against our being hit."

"You said our course would be due east, didn't you?"

"I'll change that assertion a bit, Jack; we start east after we're well
across the front, and away from the dazzling searchlight business. In
the beginning we'll point the nose of our big machine toward the north."

"So as to deceive the watchers, of course," remarked Jack.

"That's what the game is."

Jack's eyes sparkled. He was always proud of his chum's clever reasoning
powers, and believed Tom could hold his own with any one with regard to
mapping out a promising plan.

Their preparations completed, the two air service boys lay down to
secure a little rest. As they were not to start until some time after
midnight, Tom believed they should secure a few hours of sleep. The moon
was a late one, and would not rise, even with a midnight start, until
they were well back of the enemy lines.

An alarm-clock aroused them at the appointed time. Tom immediately
shoved the noisy thing under his blankets before it could wake up the
entire house, and set people wondering what was happening that any one
should want to be aroused at such an unseemly hour.

It was terribly black outside. Jack pressed his nose against the window
and took a look, even while hurriedly finishing his dressing. Tom had
taken the precaution to put a fresh battery in his little hand electric
torch, which he believed would prove to be worth its weight in gold.

Arriving at their destination, the boys quickly found their two-seater
aircraft awaiting their coming. Quite a crowd stood around, and made
guesses concerning the possible reason for the captain's order that this
plane should be made ready for a journey, with enough supplies of
gasolene and oil aboard to cover any ordinary emergency.

Tom took no chances. He believed the attendants had faithfully carried
out all directions, but to make doubly sure he looked over things
himself. It was his life and Jack's that were at stake, and not those of
the attendants; so he persisted in testing this and that thing until he
felt certain everything was as it should be.

"Is it time we started, Tom?" asked his companion, when this procedure
had resulted satisfactorily.

"We'll wait just ten minutes more," he was told. "I've figured
everything down to a fraction, and expect to proceed by clock-work. We
want to be well over the line before the moon peeps up. After that we
can loaf a bit, and let the old lady get a little way above the horizon.
That's so we may have the benefit of her light when we want to land."

The minutes passed slowly. Meanwhile the crowd increased, every man who
chanced to be abroad at that hour of the night gathering to see the two
Americans start on their mysterious errand. All sorts of guesses were
indulged in, many of them of the wildest character. Jack hearing some of
this talk, which he half understood, was convulsed in silent laughter
over the remarkable ideas that seemed to possess the minds of those
French mechanicians and hostlers.

Finally Tom stood up.

"It's time!" he said simply, and Jack understood without any further
explanation. He at once proceeded to climb into his seat and complete
his simple preparations for the work in hand, being already fully
dressed in his fur-lined garments, and with his warm hood and goggles in
place.

A minute afterwards Tom called out the word that started the propellers
whirling. The motor took up the refrain, and hummed merrily, as though
glad to be busy again. Then they were pushed along for a start,
gathering momentum so quickly that the mechanicians dropped back to
watch the dark object vanish almost wholly from their sight along the
level field.

Both boys noticed the great difference between this two-seater and their
own active little Nieuports. How clumsy this machine was, and how slow
to answer to the call of the pilot! Yet it would be far better for their
purpose than two of the small aircraft, since it allowed them to be
together.

The few lights of the aviation field near Bar-le-Duc had faded almost
entirely out of sight by the time Tom turned to the north and headed for
Verdun. True, he might have pointed the nose of the airplane directly
east, and saved considerable distance, but there were good reasons for
not doing this.

To cross the German lines further south would surely convince the
Teutons that the aviators were heading for the vicinity of Metz, which
was just what Tom did not wish to have happen. Then again, his chart
covered only the direct line between Verdun and the fortified city of
Lorraine that forty-odd years back had been French territory, before the
Germans seized it as spoils after the war that made France a republic
for the third time.




CHAPTER XV

THE MOONLIGHT FLIGHT


The time for talking had passed. With the motor working noisily, and the
twin propellers churning the air, they could hardly have heard the
discharge of one of the 'Big Berthas', as the Allies were wont to call
the monster Krupp guns, and so called them because a woman whose maiden
name had been Bertha Krupp, owned a big interest in the works where they
were manufactured.

All was dark around and below them. Above the stars shone, and gave a
small amount of cold, cheery light. Tom had made a study of the heavens,
and was able to steer by means of the stars. The aviator is often as
much dependent on compass and heavenly bodies to shape his course as the
sailor hundreds of miles away from land.

Tom was in no especial hurry. He had carefully thought out his plans,
and meant to pass over Verdun at just a certain time. Then would come
the two lines of hostile trenches, and the ordeal of searchlights and
shrapnel. Once that was done with, they had really little further to
fear.

The minutes slipped away. Under ordinary conditions they were accustomed
to making that thirty miles in just about half that number of minutes,
thanks to the ability of the speedy Nieuports to cover distance. It
would be twice that now before they would find themselves at the front.

Already they could see various signs to tell them they were drawing
near. Rockets used as signals of various kinds ascended at intervals,
and burst. Others of the star variety, and which discharged glowing
white electric balls that lighted the earth below, could also be seen.
One side or the other apparently had some reason for desiring to
scrutinize a special sector of terrain in No-Man's-Land, the disputed
region lying between the hostile trenches.

Jack used his eyes to advantage. These things had not yet grown stale
with him, for he still found himself filled with awe and wonder when
gazing down from a lofty height at the world shrouded in darkness below.

There within a comparatively short distance, that might not be over
twenty miles, a round million of soldiers were gathered, armed with
numberless engines of destruction of the most ponderous nature
imaginable. It was enough to give any one a genuine thrill, and Jack
felt such a sensation creeping over him.

The crucial time had now come. They were passing over the line of the
French trenches. Jack knew this from various signs, and also that in
another minute they might expect to be spotted by some of the enemy
searchlights. These would be unmasked, and trained on the heavens in the
effort to locate the cause of that well known clattering noise above.

This speedily came about. First one long shaft of dazzling light rushed
back and forth; then others joined in the hunt, until presently they
focussed on the progressing two-seater pushing north.

Then began the bombardment. Numerous anti-aircraft guns were poking
their noses upward in anticipation of just such a call. Their crews
commenced to shower the shrapnel around and below the bird of passage,
whose mission, whatever it might prove to be, could mean only evil to
the Teuton cause.

All this racket was lost upon the two so far above the earth. They heard
nothing of the bleat of the firing guns. Even the bursting of shrapnel
went unheeded, save at a time when a shell exploded close by, and was
faintly heard.

Tom was wisely taking but little chance. He maintained an altitude that
prevented most of the shrapnel from coming anywhere near the plane.

They crossed the enemy front, and sped on. The bombardment diminished in
fury as they left the first and second line trenches behind them. It was
continued to some extent from an elevation further back, but as Tom knew
of this formation, and had crept up still higher, no accident happened
to them.

At last the air service boys were fully launched on their night voyage
through the upper currents. Tom waited until he considered that it was
really safe to change their course. He did not want to betray his
movements in case some daring Boche pilot started up in a swift Fokker
machine to pursue them.

Once he shut off the engines and volplaned down a thousand feet or more.
This was done because it was intensely cold up where they were; and the
reasons that had kept them at such a high altitude existed no longer.
Then again Tom wished to listen to discover if there was another
aircraft near them; and this could be done only when his motor was
silent.

"No pursuit, Jack!" he managed to call to his chum before they once more
straightened out, and again allowed the motor to send forth its loud
hum.

Jack had no chance to make any sort of reply. It did not matter, for he,
too, had eagerly listened, and had failed to catch any telltale sound.

Immediately Tom shaped a new course. No longer were they heading toward
the north by east, but directly east. There some forty miles, more or
less, away, lay the city of Metz, the object of their mission.

After moving along in this fashion for a short time Tom drove his
machine more slowly. He was watching for the rising of the old moon
ahead, where the horizon was already lighted with her near approach.

How strange she looked peering above the edge of the world as though
curious to see all that was going on in this troubled hemisphere. Jack
thought he had never witnessed a more peculiar spectacle. But at least
this fragment of a moon would be likely to afford them the necessary
illumination required when they attempted to land in a field that
neither of them had ever seen before, and only knew through information
imparted by means of their chart, and its accompanying notes.

Some other pilot had doubtless been over this same route on previous
occasions; yes, and even landed in that identical field. He had made the
chart; and the accompanying memoranda consisted of his personal
experiences.

Already the moon had dispelled some of the cheerless gloom round about
them. It was still cold up in that upper strata of rarefied air; but
their fur-lined garments kept them from suffering. Besides this, they
were young and vigorous, and their blood was warm, and they were excited
with their mission and able to ignore any physical discomfort that might
come to them.

Jack continued to stare ahead as time passed. He was looking for some
sign of the city towards which they were flying. Tom, on his part, often
took note of his compass, then flashed a glance up at the stars, and
finally sought to discover some landmark far down below that was marked
upon the chart.

He had the utmost confidence in his own judgment, and believed he would
bring up at the identical place which was their goal.

Tom now volplaned again, wishing to draw nearer to the earth. It was
while thus dropping, with engine muffled, that his ears caught a sound
calculated to give him an uneasy feeling.

This was undoubtedly the whirr of a propeller beating the air in furious
fashion. It also came from behind. Jack, too, had caught the sound, and
was thrilled with sudden apprehension of impending trouble.

They were undoubtedly being pursued, and by a much faster plane than
their own. This would mean that presently they would be overtaken and
fired upon. It was not in the nature of Tom Raymond to allow such a
thing to occur and be kept from doing his share of the fighting.

When Tom swung around to face the rear, and actually started to run
toward the oncoming foe, Jack knew what was expected of him. He must man
the gun, and prove how well he had learned his lesson when at school at
Pau and at Casso.

No longer could they expect to be guided by sounds. Their own motor
thundered so loudly that every other sound was deadened. They must
depend on eyesight alone to tell them when they were nearing the
oncoming Fokker craft. Perhaps the first indication they would have of
its presence would be the flash of its quick-firing gun, spattering
bullets around them like hail.

So Jack strained his vision to the limit. He was eager to discover the
enemy before they themselves were seen. Much might depend on who fired
first, in a duel of this kind.

Suddenly the gun began to bark after its own peculiar way. Jack believed
he had glimpsed something moving, and was sending forth a storm of lead
in the hope of a lucky hit that would crumple the other machine up and
put an end to that peril.

Tom held the course. He knew that every second was carrying the rival
airplanes nearer together--knew that possibly they were so headed that
if they continued to rush forward they might smash in a frightful
collision that would send both down thousands of feet to the earth.

It was a time for careful calculations and prompt action. Tom gripped
the controls and was ready either to swerve or to dip as occasion
demanded. Meanwhile, Jack was doing his best to riddle the advancing
Boche machine and its pilot.

There was no longer any difficulty in seeing just where the Fokker was,
for a constant flashing as her gun rattled betrayed its position
exactly. The flying lead was now whistling all about the two air service
boys but they did not know how close they sailed to death.

Then Tom swung smartly to the right. He dared not keep on longer in his
course lest he collide with the German craft. Just about the same
instant he realized that the Fokker was diving. There was something
queer about that manoeuvre. Tom had never known a French or an American
nor yet a British airman to adopt such a clumsy way of plunging so as to
avoid punishment.

Circling around he started back on a little lower level, looking for the
enemy. In making his latest volplane Tom had listened intently, hoping
to ascertain whether the motor of the enemy craft still throbbed
somewhere close by; but he heard not a sound to tell the story.

Just then, suspicious of the truth, he glanced down, and was just in
time to see a little flash of flame arise from the distant surface of
the earth. Then the awful truth broke upon both boys. They realized that
the German pilot had lost control of his machine, which had turned over
and over in its drop, finally crashing to the ground, and being
instantly enveloped in flames!




CHAPTER XVI

LANDING CLOSE TO METZ


Tom had his hands full in trying to get back to his course again.
Naturally, in the excitement attending the duel in midair he could not
pay attention to where he was going. It was easy enough to shape his
line of flight by the aid of the stars and his compass, but he had also
to catch certain landmarks below, that would serve to guide him.

Fortune favored him in that he quickly sighted the lights of a town; and
this gave him the bearings he sought. His mind freed from further
anxiety concerning this matter, he pushed on once more.

When presently he became aware of the presence of more lights Jack gave
Tom the signal agreed on between them to mark such a circumstance. Then
the pilot again commenced to drop to lower levels by a series of easy
volplanes.

Like a huge bird the airplane swept along, now close to earth. Had one
of the peasants who lived in that region chanced to be aroused by the
rattle of the propeller and thrust his head out of his cottage door, he
must have gazed in awe to see the vast shadowy form come between him and
the starry heavens, with the light of the moon silvering its extended
wings.

One trip failed to show them just what they wanted, and so Tom, knowing
that the field must be somewhere in that immediate neighborhood,
immediately swung around and started in again.

The second search failed to bring success. Jack began to experience a
sensation akin to dismay. Was their work doomed to meet with no result
and would they find themselves compelled to start back to Verdun without
having accomplished the important errand on which they had been
dispatched?

It was not Tom Raymond's way to feel discouraged because things did not
always go as he wished from the start. He believed in the old motto, "If
at first you don't succeed, try, try again." And he would circle around
that vicinity for a full hour if only in the end he might find that for
which he searched.

Three times however, was the limit. Then Tom felt certain he had "struck
pay dirt"; and that the opening lying below was the identical field to
which he had been directed.

After that it resolved itself into a simple landing by moonlight. There
were no ready mechanicians waiting to lend a hand; and everything must
be done by the pilot and his assistant. But then, all war aviators must
be able to make ordinary repairs if necessary, and do other duties that
usually they allow the mechanics to perform.

Tom brought the heavy machine to the earth softly. It was fine work he
did, considering the fact that it was unfamiliar ground he was striking
and the moonlight was far from strong.

They jolted along a short distance, and then came to a full stop. Jack
was the first to spring out. His first thought was of the strangeness of
being on German soil, far back of the fighting lines, and within a few
miles of Metz, a city of prime importance.

Hardly had they landed when the air service boys found themselves
listening to sounds that seemed significant. Plainly came reports of
firearms and of loud shouting, as of excited men.

"What do you think that row means, Tom?" asked Jack, as they stood
listening with quickened hearts.

"It's hard to say," the other replied. "They may be having a riot of
some kind over in the city. But I'm afraid it is more apt to have
something to do with our presence here."

"Do you mean they've seen our dropping down and that there may be
soldiers on the way here to see what we're up to?" asked Jack.

"That may turn out to be the truth of it. But we mustn't lose any more
time. What we want now is that paper. Jack, remember that we arranged it
so you'd stay with the plane, while I hurried off to get it."

"All right, Tom; only I wish you'd let me go along. Then if anything
happened we'd be together, anyhow."

"It's better for you to stay here. I'll be gone only a few minutes if
everything turns out O.K."

Tom turned and ran across the field. Jack stared after him until he lost
track of the runner in the misty moonlight. Then he occupied himself in
listening to that clamor and wondering whether it was really getting
closer, or if his fears only made him think so.

There was certainly a big noise. Men continued to shout, and guns were
being discharged, but not so frequently as before. Perhaps this latter
was done by nervous guardians of the Lorraine city, who on first hearing
the racket took it for granted that it meant an airplane attack, and
were therefore starting in to bombard the skies, discovering hostile
fliers in every lurking fleecy cloud.

Yes, Jack was positive now that those who shouted to one another must be
coming out of the city, and heading for the big field where Tom had
dropped down.

"Like as not," Jack told himself, "some wisebody has discovered that
airplanes have been using this ground for alighting. When they had word
that an enemy machine was heading this way they just naturally concluded
it might drop down here. I guess our little fight up aloft was heard and
understood by some one on guard. I hope Tom will soon get back here,
that's what!"

Tom had been gone several minutes, and Jack tried to pierce the misty
light beyond in the endeavor to discover some sign of his returning. His
uneasiness increased, and with reason, for the noise was drawing
perilously near.

Jack tried to figure out what his plan of campaign should be in case a
motley mob of citizens and soldiers suddenly appeared in view, carrying
lanterns, and perhaps blazing torches.

True, he had his automatic pistol with him, but what would that puny
weapon avail when pitted against a score or two of enemies; many of them
armed soldiers of the Kaiser, who would ruthlessly fill him with lead at
the first show of resistance on his part?

Would it be better policy for him to slip away and conceal himself in
case they did arrive before Tom returned?

But had not Tom explicitly told him to stay on guard over the airplane
until he came back? Jack drew in a fresh breath. He threw back his
shoulders aggressively and his mind was made up. He would stick it out,
no matter at what cost. If the Boches wanted that plane they would have
to fight for it, that was all.

He had his pistol out now, and was fondling it as a child would a pet
toy. So far Jack had fired the weapon only at targets, but he had the
reputation of being a good shot. He believed he could make every bullet
it contained tell.

Then what about the mitrailleuse aboard the plane? Was it not possible
to train it on the advancing host, and give them such a hot reception
that they would break and race madly for shelter?

He knew the gun was fixed to shoot straight ahead. This was the custom
with all those who went up in airplanes. To attempt to fire any other
way would imperil the stability of the plane, and in many cases bring
about sudden disaster.

Jack fumbled for the fastenings of the airplane mitrailleuse, it being
his intention to swing the gun free, so that he could turn its muzzle in
any quarter desired. But it had been too well secured in place for such
a quick delivery, and presently he gave the idea up as a bad one.

No Tom yet! Things certainly were taking on a dark hue, and it looked as
though desperate trouble might be in store for the two chums. Jack
almost believed he could see dancing lights coming along what might be a
road. He looked again, and no longer had any doubt on that score.

"Well, a fellow can die only once, and after all what does it matter
whether he meets his end by falling ten thousand feet from the clouds or
in trying to hold off an angry mob of Teuton soldiers and citizens of
Metz who are in sympathy with the methods of the Kaiser?" Jack's
reflections served to give him courage.

There was the leading one of the mob, starting across the dimly lighted
field! Jack set his jaws hard, and determined that he would wait until
the other had come close up. Ammunition was much too precious to be
wasted without results following.

He was soon glad he had made such a sensible resolution, for as the
runner drew closer something familiar about his figure and methods of
leaping told Jack it was none other than Tom.

"Get aboard in a hurry, after you've given the propellers a swing!"
cried Tom, almost breathless himself after such a sharp run. "I've got
what I wanted."

He was already in his place with his hand on the control.

"Tell me when, Tom!" sang out Jack.

"Cut loose!" ordered the pilot.

The propellers spun, and the motors commenced their furious throbbing.
Jack swung aboard, and at once the plane started to roll along the
field, even as men appeared, bursting into view on one side, and
shouting harshly as they realized how close they had come to catching
those they sought.




CHAPTER XVII

MORE TROUBLE FOR THE CHUMS


It had been a close call for the two air service boys. Had they been
delayed just a minute or two longer escape might have been impossible.
And to have been caught with the spy's paper of information in their
possession might have proved a very serious matter.

Some of the mob, that had come from Metz itself, were German soldiers.
They carried guns with which they opened a hot fire on the departing
plane.

Again the lucky star of Tom and Jack seemed to be in the ascendant, for
they did not receive even a scratch. Later they found reason to believe
that a number of the leaden missiles had come very close to their
persons; for the marks upon the body of the plane itself, as well as the
tiny holes in the stout linen covering of the wings, told where bullets
had passed. Possibly, though, these had come from the rapid-fire gun
handled by the Boche airman.

The plane had left the ground and started to mount when this shooting
occurred, so that the marksmen had at least had a fair target at which
to fire. But as the departing airplane was speeding away from them the
rapidly increasing distance may have disconcerted the Germans. At any
rate they failed to bag their game.

The boys were now mounting upwards again, filled with joy over their
recent escape. Jack felt sure that Tom had the precious paper; for he
well knew the other would never have returned so quickly had not success
rewarded his search.

They were soon heading directly for their distant base. Tom could now
give his aerial steed the rein, and get all the speed possible out of
the cumbersome two-seater. There was no longer any necessity for
"loafing on the job," to allow a tardy moon to come in sight, as had
been the case before. Home, and at top speed, was the slogan now.

But, alas! it was not long before Tom realized that something was wrong
with the plane. He found it increasingly difficult to manage the engine,
and the machine began to give erratic jumps that alarmed Jack.

Had it been possible to make himself heard above the clatter of the
motor and the propeller, Jack would have been much inclined to shout
out, and ask his more experienced comrade what had happened.

Still he could give a shrewd guess. One of the bullets fired by the
Teuton soldiers must have struck some part of the motor, and done enough
damage to make its workings exceedingly erratic. If such were the case,
would it be wise for them to try to push on at this high altitude, where
a sudden collapse would mean death for both of the occupants of the
disabled plane?

Tom soon shut the motor off, and tilted the machine for a volplane down
several thousand feet to a new level.

Jack held his breath. This was partly because the wind rushed at him in
a vicious fashion while they were plunging downward, and also on account
of a new fear that clutched his heart.

How about the wings of the airplane standing the strain when Tom
suddenly brought that volplane to a stop and tried to sail on an even
keel again? Would they hold out? Or had some defect occurred in them
which could also be charged to the spattering bullets fired by the Metz
mob?

Then Jack breathed easier again.

The thing had been accomplished, and they were once more speeding
onward, as Tom touched the controls that started the motor working. All
then was well, as far as they had gone. Apparently they could by
successive stages descend close to the treetops, and skim along until
some favorable open space showed, into which a skillful pilot would find
it possible to drop lightly and land.

A second volplane further added to Jack's peace of mind. They were now
halfway down, and all seemed well. The earth loomed up below, although
as yet it took on only a vague, misty effect, due to the weak moonlight.

Jack busied himself in trying to make things out, as for the third time
the nose of the heavy observation Caudron was suddenly pointed downward,
and they took the next "header."

This time Tom dropped a greater distance. When once more the loud hum of
motor and propellers was heard they had almost reached the treetops.
Jack gave one gulp, in fear lest his pilot could not make things work as
he intended, and that they must crash to the earth while descending at
such frightful speed.

Now everything was all right. They could not be more than a thousand
feet above the floor of the valley they were following in their homeward
route. If anything happened surely Tom would find some way of making a
landing, even if a clumsy one that would put their machine out of the
running and leave them stranded on enemy soil.

They continued to move along slowly, both looking eagerly to discover
signs that would invite a possible landing. It looked as though they
were in the country; at least they did not discover any signs of lights
to indicate the presence of houses near by.

Soon a landing proved feasible, as they came to just the kind of open
plot the air service boys yearned to discover. To make absolutely
certain before committing himself, Tom circled the ground twice, and
even dropped lower and lower while so doing, all the while straining his
vision to the utmost.

Then the thing was done.

That was far from a pleasant landing. It shook them up considerably; but
Jack was of the opinion that no damage resulted to the airplane, which
after all was just then the main consideration.

Both of them leaped to the ground, after which Tom secured his electric
hand-torch which he had found useful so many times while on the outward
trip and he wished to consult the compass or the register of the
barograph.

"I guess there's some sort of a house near by," said Jack, "because a
rooster crowed over yonder. Yes, I can see what looks like the line of a
road, too. I suppose it runs the entire length of this valley."

While Jack was saying this softly the pilot had started to take an
inventory of the motor. His now practiced eye ran along this and that
part, each of which was so essential to the smooth running of the
engine. Tom too had already formed a pretty clear idea as to where he
was likely to find the damage, and hence was able in a short time to
give a satisfied grunt.

"Located the trouble, have you, Tom?" queried the other.

"Yes. It's right where I expected to find it. A bullet has made a dent
that interferes with the free action of the part. Besides, I think that
spark plug has become fouled with oil, and will have to be changed to
get the best results."

"How lucky you brought another with you! Lots of fellows wouldn't have
bothered about such a little thing."

"I had my suspicions about that when we started," explained the other,
"even though the mechanician assured me it was perfectly clean. I know
different now, and will certainly give him a piece of my mind when we
get back."

"Then you expect to get home safely, do you?" asked Jack, in a relieved
tone, that proved how anxious he had been growing since troubles had so
consecutively alighted on them.

"Surely," chuckled the other, with his usual confidence in voice and
manner, "a thing like this isn't going to stop our plans. Here in this
retired spot nobody's apt to bother us while we make our repairs. You
can hold this torch, Jack, and shove the light squarely on the work."

Tom worked for some time. He tapped as gently as possible when knocking
out the dent made by the bullet, and he gradually removed the cause of
the trouble. He was just finishing with the spark-plug when the
confidence of the air service boys received a sudden jolt.




CHAPTER XVIII

THE LONE HOUSE BY THE ROADSIDE


"Listen, Tom!" hissed Jack.

The other had just sighed with relief on completing the work of
replacing the spark-plug that had become fouled with oil.

"I, too, heard it plainly, Jack!" he breathed.

"Was it someone screaming or sobbing?" asked the other breathlessly.

"Sounded like it to me."

"And either a woman or a girl, at that!" hazarded his chum in
bewilderment.

"It might have been a boy," suggested Tom. "There it is again."

Both of them listened. Peculiar sensations crept over them as they stood
and thus strained their ears to catch any further sounds. Sobbing at any
time is enough to arouse the feelings of a sensitive nature; but heard
in the dead of night, and under the conditions that surrounded the two
young aviators, made it all the more thrilling.

Jack in particular was touched to the heart.

"Say, that's a queer thing, Tom!" he muttered. "Why should anybody be
crying or screaming like that away off here, and at this time of night?"

"Oh, there are many who are weeping in these dark days," said Tom
gravely. "The men in myriads of families will never come home again.
Perhaps a mother, or it may be a sister, has just had word that son,
father, or brother has been shot down in battle."

Jack shuddered. Why should his thoughts instantly fly to the Boche pilot
whom they had met and fought and conquered while on the way to Metz on
their present perilous mission? It had been a fair fight, and a case of
their lives or his. Nevertheless Jack shuddered as he remembered how the
other had gone down after that last exchange of gunfire.

"Tom, notice that it comes from almost the identical direction where I
told you I heard the crowing of a rooster a while ago," he hastened to
say, more to rid his mind of those ghastly thoughts than anything else.

What a strange fatality if this should be the home of the unfortunate
Teuton pilot of that Fokker machine, and the one who mourned was his
mother or a young sister, or perhaps his wife!

"That means there's a house not far away, possibly an estate of some
kind," mused Tom, as though turning over some sudden project in his
mind.

Jack guessed what his chum was thinking about.

"Tom," he said softly, when for the third time they caught the
heart-rending, half stifled sobs coming on the still night air.

"What do you want now, Jack?"

"I was just wondering whether you'd agree to something," continued the
other, in a persuasive tone. "We're not in any _great_ hurry, are
we?"

"Well, no, perhaps not, Jack; though I'd like to deliver the paper into
the hands of our commander as soon as possible. It is probably of the
utmost importance, you know."

"I can't help thinking how I'd feel, Tom, if my mother or sister were in
some great trouble, and fellows who might be in a position to hold out a
helping hand considered their own personal safety first."

When Jack said this his voice was husky. Apparently the incident
appealed strongly to his emotions. Jack had always been unusually
thoughtful in regard to women of whatever age or degree, and would go
far out of his way to do one a favor; so it was not strange that he
should feel as he did at this time.

Tom was in a mood to be easily persuaded. The plaintive sobs, telling of
woe that clutched some one's heart-strings, stirred a responsive chord
within him. He, too, remembered those at home. Jack had put a clincher
on his argument when he asked what their opinion of a man would be who
turned aside and went his own way after hearing a woman or a child
crying bitterly.

"All right, then, Jack; perhaps we can spare the time to take a turn
around here, and see if we can be of any help," he announced, greatly to
the satisfaction of his chum.

"Perhaps some one has been hurt and needs assistance," suggested Jack.
"It isn't going to delay us much, and may be of great help to them. Come
on--let's be on the move."

Tom was not quite so precipitate as his companion. Caution had a part in
his make-up.

"Don't try to rush things, Jack," he said. "I must take a last look over
my work here, you know."

"But you said everything was completed, Tom!" persisted the other.

"So it is, but I ought to make doubly sure before we leave the plane,"
Tom added, as he took the electric hand-torch from his companion and
began systematically to look over the engine at which he had been
working, carefully examining every detail.

Jack said nothing further. He understood what his chum meant when he
declared it important that they should know absolutely the motor was in
prime condition for immediate service. Something might occur to
necessitate a hurried departure from the vicinity; a detachment of the
enemy forces might appear, or other perils hover over their heads that
might be laughed at only if they could take to the air without
detention.

Tom was not long in doing as he desired. Meanwhile Jack could hear an
occasional sob from the same quarter as before, and the sounds continued
to exercise a peculiar influence over him which he could not have
explained had he been asked.

"I'm ready now, Jack!".

"Glad to hear it," muttered the other, half under his breath; not that
he meant to infer Tom had been unduly long, but because his feelings
were wrought up to a high pitch that caused him to quiver all over.

Tom evidently guessed this, judging from his next remark.

"Cool down, Jack," he said, laying a hand on his companion's arm. "This
will never do, you know. Getting excited is the worst thing an air pilot
can do. It'll prove fatal to all your hopes, unless you manage to
control your feelings better."

"I guess you're right, Tom."

"I don't think there's any chance the plane will be discovered here in
the open field, even if there is a road so close by," mused the pilot,
after they had gone perhaps as far as twenty-five yards.

"Not in a thousand years," asserted Jack confidently, turning to look
back as he spoke. "Why, even now I can't discover a sign of the wings,
or anything else in the misty moonlight, it's so deceptive. Only that
lone tree standing close to where we dropped tells me the location of
our plane."

"Yes, I marked that, too," asserted Tom quietly. "I thought we ought to
have some sort of landmark to guide us if we should be in a hurry coming
back. And the tree, standing up fairly high, can be seen ten times
better than anything close to the earth."

"Here's the road, Tom."

"So it is, and an important one in the bargain, judging from its
condition," remarked the other, softly.

"It runs the length of the valley, of course," added Jack. "I shouldn't
be surprised if it went all the way from Metz to the Verdun front. If
that's the case it must have considerable travel, even if nothing has
chanced to come along since we landed."

"I can see signs to tell that we are close to some sort of country
estate, or it may only be a Lorraine farm."

"I can glimpse lights through the trees, and chances are they come from
windows in the house beyond."

"I see them too," affirmed Tom.

"But say, isn't it pretty late for a farmhouse to be lighted up like
that?"

"Depend on it, there's some good reason for all that illumination," Jack
was told. "And perhaps we'd better drop this talking so much, now we're
getting close to the place. No telling what we'll find there. For all we
know this may be some one's headquarters, though pretty far back of the
line for that sort of thing. But I think it'll turn out to be something
more than ordinary."

It did.

Jack began to weave all manner of fantastic explanations to account for
the illumination of the house alongside the road to Metz.

He felt he would not be very much astonished to discover a line of
military cars standing at the gate, and find that an important council
of war was being conducted within the building.

Then he remembered the crying and sobbing. Somehow, that did not seem to
fit in with his other imaginings. The touch of Tom's hand on his arm
made Jack give a violent start.

"Here's a high fence, you notice," Tom whispered. "Seeing that makes me
believe it's going to turn out to be a country estate, and not just a
farm. We ought to find a gate somewhere further along."

"That crying has stopped, Tom."

"For the time being, yes," admitted the other. "Perhaps she's only gone
away from the open window. I was in hopes it would keep on, so we could
be guided straight."

Two minutes later, after walking alongside the high fence for some
distance, they discovered the entrance to the place. Tom flashed his
light on the ground.

"Been considerable going in and coming out of vehicles, generally
automobiles," he announced.

"And private cars are almost taboo in all Germany these dark days, they
tell us," mentioned Jack sagely. "That makes it look as if some sort of
military business might be transacted in this isolated place. Gee! I
tell you it's getting my curiosity whetted to a fine point, all this
mystery. But we're going in, of course, Tom?"

"Some way or other, Jack. If the entrance is closed and locked we can
climb over the fence, all right. But no need of worrying about that,
because I already see the gates are ajar. Come on."

So they slipped into the enclosed grounds, actuated by an impulse,
wholly unconscious of what might be awaiting them. They had been drawn
into the adventure simply on account of a praiseworthy desire to be of
service to some unknown one who seemed to be in trouble. And neither of
the boys even vaguely suspected as yet what strange happenings would
confront them before many minutes passed by.




CHAPTER XIX

A NEST OF SPIES


Neither of the air service boys had any doubts now with regard to the
character of the grounds they were invading at dead of night. It must be
a private estate. Once it may have been kept up through a lavish
expenditure of money, but of late years things had evidently been
allowed to grow more or less wild.

Tom was following what appeared to be the drive. It was not difficult to
do so, because of the moonlight that sifted down through the bare
branches of the neighboring ornamental trees, now destitute of foliage.

The house was presently discovered. Just as Tom anticipated, it was a
rather large building, that might even be called a mansion, or château.
It lay half buried amidst a prodigious growth of trees and bushes.

Jack fancied there was a sort of haunted air about the place, something
uncanny, as he told himself. And then those sobs or screams could not be
forgotten.

"Let's go around first, and see what lies in the rear," whispered Tom.

He had an object in view when he said this. Having noted carefully their
route in coming from the open field where they had left their big plane,
Tom knew that the window from whence the sobbing had come must be either
at the back of the house, or on the eastern side.

He was heading in that quarter now, and looking for signs of a light in
some upper window. This he discovered speedily, and pointed it out to
his companion.

"Whoever was crying, Jack, must be up there," he said, close to the
other's ear so as to insure safety.

"But how can we find out?" queried Jack. "If you say the word I'm
willing to climb up, and learn what's wrong."

"Not yet. We must take a turn around, and pick up more knowledge of this
place, as well as the people who live in the house."

"Then why not creep up and look in at that lower window?" suggested
Jack, pointing as he spoke. "I've seen a shadow passing back and forth,
as if some person were walking up and down like a caged tiger. It's a
man, too, Tom, because I could easily make out his figure, a tall man to
boot."

Tom led the way, with Jack at his heels. They managed to crawl through
the bushes that cluttered the ground close to the wall of the stone
building, and were at length in a position to raise themselves from
their knees and peep under the drawn shade.

Jack was the first to look. Almost instantly he drew back with a low
ejaculation of wonder. Tom, spurred on by this fact, also raised his
head until his eyes were on a level with the small strip of open space
just below the shade. He too had a thrill at what he saw.

"I feel as if I must be dreaming!" whispered Jack huskily. "Tell me, is
that man in there really Carl Potzfeldt, the good-for-nothing guardian
of little Bessie Gleason?"

"It's no other than our old acquaintance of the Atlantic liner,"
admitted Tom, though he himself had some difficulty in believing the
startling fact.

This man, whom they felt sure was a German spy, had last been seen
descending the gangway from the steamer at an English port, with Bessie
Gleason, his pretty little ward, held by the hand, as though he feared
she might try to run away from him.

Many times had Jack tried to picture the conditions under which he might
run across Carl Potzfeldt again; but no matter what line of flight his
imagination took he certainly had never dreamed of such a thing as this.
Here in the heart of Lorraine, many miles back of the German front, on a
moonlight night, and in a lonely country house, he once more beheld the
object of his former detestation.

He clutched his chum by the arm almost fiercely.

"Well, that settles it, Tom!" he muttered savagely.

"Settles what?" whispered the other, for the window was closed, and
there did not seem to be any chance of their low-voiced exchange of
opinions being overheard.

"I don't leave here until I've seen _her_. For if he's at this
place it stands to reason Bessie must be here also. Tom, that was Bessie
we heard sobbing, I just know it now."

Tom had already jumped to the same conclusion. Nevertheless he did not
mean to let it interfere with his customary caution. Nothing was to be
gained through reckless and hurried action. They must go slowly and
carefully. This house by the roadside on the way to Metz he concluded
might be a nest of spies, perhaps the headquarters of a vast network of
plotters.

"Hark! There's a car coming along the road and stopping at the gates
here!" he told his chum, as he drew Jack down beside him. "We must be
more careful how we look in lighted windows. If any one chanced to be
abroad in the grounds we'd be seen, and perhaps fired on."

They crept from the vicinity of the window. Tom led the way toward the
front of the house, as if he had an object in view. The car was now
coming in along the crooked drive. They could see its one light, for
economy in the use of all means for illumination was a cardinal feature
of the German military orders in those days of scarcity.

The car stopped in front of the house, and a man jumped out. Tom saw
that he wore a uniform of some sort, and judged that he might be a
captain, at least. There was a second figure on the front seat, also in
the dark-green garb of a soldier, but a private possibly.

The two young Americans crouched amidst the dense bushes and listened.
So many thrilling things were happening in rapid succession that their
pulses beat with unwonted speed.

Before this the sound of the approaching car must have reached the ears
of the man they had seen pacing the floor in the spacious room that
looked like a library. There were many books in cases and on shelves,
while pictures and boars' heads decorated the walls.

Potzfeldt opened the door just as the officer alighted, and there was an
exchange of stiff military salutations. Tom discovered that his guess
was a true one, for the man of the house addressed the other as
"Captain."

It was too bad that they spoke in German as they stood by the open door.
Jack for once bitterly regretted the fact that he had never taken up the
study of that language when at school, as he might have done easily
enough. It would have paid him handsomely just then, he believed.

The two men talked rapidly. Apparently the officer was asking questions,
and demanding something, for in another minute Carl Potzfeldt took an
object out of a bill book and handed it to the other. As near as the
watchers could make out this object was a slip of paper, very small, but
handled as though it might be exceedingly precious.

Jack had a sudden recollection of a correspondingly minute slip of paper
which he and Tom had found hidden in that little receptacle attached to
the leg of the homing pigeon the latter had shot.

More talk followed between the two men. Presently the man turned and
hastened inside again. He had left the door standing open, however, with
the German officer waiting as if for something he had come after besides
the scrap of paper.

Jack knew now that the man in uniform was from the headquarters of the
Crown Prince. That accounted for the numerous marks of car tires which
Tom had discovered on the drive. This lonely house by the roadside on
the way to Metz was a nest of spies. Perhaps Carl Potzfeldt might be the
chief, through whom negotiations were conducted and lesser agents sent
forth.

Jack had got no further in his deduction when he saw the tall man
returning. He carried a bundle that was wrapped in a cloth, and depended
from his hand by means of a heavy cord, or some sort of handle.

This he set down on the landing, while he passed further words with the
captain; and now it was Potzfeldt who asked the questions, as though he
wished to learn how things were going at the front.

Between queries and guttural replies the hidden air service boys heard a
series of sounds that gave them sudden light. Jack's hand pressed on
Tom's arm, as though in this manner he wished to call the attention of
the other to the noise.

Many times both of them had listened to similar sounds while watching
some pigeon on the barn roof dare a rival to combat, or when wooing his
mate. And as they could easily trace this to the covered package which
Carl Potzfeldt had just brought out of the house, the meaning was
obvious.

Of course there were pigeons in that cage, homing pigeons at that, like
the one Tom had shot! Doubtless had that one escaped its tragic fate the
message it carried would have been delivered to the owner of this lonely
house, in turn to be handed over to one of the messengers from German
headquarters.

And now the German captain, stooping over, took possession of the cage
containing at least two of the trained birds. They would be carried to
some point from which, on another night, a daring Boche airman would
attempt to take them far back of the French front, to hand over to the
agent who was in communication with the master spy, Carl Potzfeldt.

It was all very simple. Nevertheless it was also amazing to realize how
by what might be called a freak of fate the air service boys had been
enabled to discover these facts. But for the accident to the motor they
would not have dreamed of making a landing short of the aviation field
at Bar-le-Duc. Then, had they not caught that woeful sound of loud
sobbing, the idea of looking around would never have occurred to them.

The officer was now starting back to his car, which would carry him
post-haste to German headquarters, where the fresh message in a cipher
code from beyond the French lines might be translated, and the valuable
information it possibly contained be taken advantage of.

Presently the military chauffeur started to swing around a curve that
would allow them to leave the grounds by the same gates through which
they had entered. The car's course could be followed by the strong ray
its one light threw ahead; and the boys were able to tell when it
reached the road again.

As they expected it returned the same way it had come, probably heading
for the headquarters of the Crown Prince.




CHAPTER XX

JACK CLIMBS A WALL


"What luck we're in to be here, Tom!" murmured Jack.

Carl Potzfeldt had again entered the house and closed the door; and the
air service boys could no longer hear the car speeding along the road.
Jack was quivering all over with excitement. The events that had just
come to their attention filled him with a sensation of wonder
approaching awe.

"It certainly is strange how we've stumbled on this nest of spies,"
admitted Tom.

"And the paper he gave the captain--it must have been a message in
cipher that an incoming pigeon brought from back of our lines, eh, Tom?"

"I guess it was, Jack. We could see it was only a small scrap of paper,
thin paper at that; but both of them handled it as if it were pretty
valuable."

Jack was chuckling, such a queer proceeding that Tom could not help
noticing it, and commenting on it.

"What's struck you as funny now?" he asked, puzzled to account for this
sudden freak on the part of his companion.

"I was wondering," explained Jack, "whether that mightn't be the
doctored message we believed our commander meant to send through some
time or other with one of the pigeons we got that day we went hunting."

"That's possible," Tom agreed, also amused at the thought. "But then,
whether it is or not, it means nothing to us, you understand. We are
here, and must decide on our movements. If that was a bogus message, and
will coax the Germans to make an attack at a certain place where a trap
has been laid, that's their lookout."

"Somewhere about here must be the pigeon loft where those homing birds
have been bred," suggested Jack, following up a train of thought.

"Yes, it may be on the flat roof of the château, or in the barn at the
rear," Tom admitted. "One thing is certain, they know only this place as
home; and wherever they're set free their first instinct is to strike a
bee-line for here. Some people are so foolish as to fancy homers can be
sent anywhere; but that's silly. It's only home that they're able to
head straight toward, even if hundreds of miles away."

"Oh Tom! how about Bessie?" inquired Jack eagerly.

His chum considered, while he rubbed his chin with thumb and finger in a
thoughtful way he had when a little puzzled.

"It might be done in a pinch," he finally muttered.

"What, Tom?"

"She's such a little mite that her weight wouldn't amount to much, if
only she had the nerve to do it, Jack."

"Do you mean that you'd be willing to carry Bessie off with us? To help
her escape from her guardian? I'm sure he must be treating her badly, or
else she wouldn't be sobbing her poor little heart out, as we heard
her."

"That would have to depend a whole lot on Bessie."

"As far as that goes I know she's a gritty little person," Jack
instantly remarked. "Many times she said to me she wished she were a boy
so that she might also learn to fly and fight for France against the
detested Kaiser. Why, she even told me she had gone up with an aviator
who exhibited down at a Florida resort, one having a hydro-airplane in
which he took people up. And Bessie declared she didn't have the least
fear."

"That sounds good to me, Jack."

"Then let's get busy, and try to let her know we're here," continued
Jack.

"First of all, we'll get under the open window where she must have been
standing at the time we heard her crying. I think I saw a movement up
there while the two men were conversing on the porch. Perhaps Bessie was
listening to what they said."

Tom's words gave his chum a new thought.

"Oh, it would certainly be just like Bessie to do it! She seemed to be
full of clever ideas."

Tom, being mystified by such words, he naturally sought further
information.

"What would she do?" he demanded.

"Send me that mysterious message by the little hot-air balloon," Jack
announced with a vein of pride in his voice, feeling delighted over
having solved the puzzle that had baffled him for so long.

"It hardly seems probable," Tom answered softly. "At the same time it
isn't altogether impossible."

"How far are we from the French front, do you think, Tom?" pursued his
comrade, determined to sift the whole thing out.

"Twenty miles or so, I should imagine."

"That isn't very far. Once I caught just such a little balloon in a tree
in our yard that had a tag on it, telling that it had been set free in a
village that lay _seventy_ miles off. The wind had carried it along
furiously, so that it covered all that distance before losing buoyancy,
and coming down in the heavy night air."

"Yes, I know of other circumstances where such balloons have traveled
long distances before falling. Then again, Jack, this valley extends
pretty much all the way to the Verdun front, and the current of air
would carry a balloon along directly toward our home patch."

"Oh, Bessie sent it, believe me!" asserted Jack again, more confidently
than ever. "And she'll tell us so too, when she gets the chance."

Thus whispering the air service boys arrived at that side of the house
where the lighted window on the second floor seemed to indicate that the
object of their present concern could be found.

Tom examined the building as well as the limited amount of light
allowed. He could easily see that any agile young fellow, himself or
Jack for instance, might scale the wall, making use of some projections,
and a cement flower trellis as well, in carrying out the project.

"We might throw pebbles up, and bring her to the window," he suggested,
though pretty confident at the time Jack would find fault with such an
arrangement.

"That wouldn't help her get down here to us, Tom," protested the other.
"And that's what we're planning, you remember; for you said she could
accompany us if she felt equal to it. I must go up myself and help
Bessie get down. There's nothing else to do, Tom."

It looked very much as though Jack was right. Tom admitted this to
himself; at the same time he wished there were some other way by means
of which the same end could be gained, or that he could undertake the
thing, instead of his comrade.

But to this Jack would never agree. Bessie was his own particular
friend; and they had been most "chummy" while aboard the Atlantic liner
crossing the submarine infested ocean. Then again that warning had been
addressed to him, and not to both, showing that the writer had only been
concerned about the danger he, Jack, was running, should his plane be
tampered with by some emissary of Carl Potzfeldt.

"All right then; you go, Jack! But be careful about your footing. If you
fell it'd be a bad thing in many ways, for even if you escaped a broken
neck or a fractured leg you'd arouse the house, and all sorts of trouble
would drop down on us in a hurry."

"Don't worry about me, Tom. I'll show you I'm as nimble as any monkey.
Besides, that isn't much of a climb. Why, I could nearly do it with one
arm tied fast."

"Go to it!" Tom told him, settling back to watch the performance and
give whispered advice if it seemed necessary.

Jack waited no longer. He was wild to find himself once more face to
face with the pretty young girl in whom he had taken such an interest.
Her recent sobs and cries still haunted his heart, and he felt certain
she must be in great sorrow over something.

He commenced climbing. While his boast about being equal to any monkey
that ever lived among the treetops may have been a bit of an
exaggeration, all the same Jack was a very good athlete, and especially
with regard to feats on the parallel bars or the ladders in a gymnasium.

He made his way nimbly upward, with Tom's eyes following every movement.
It seemed an easy task for the climber. Just what he would discover when
he had gained the open window was another question.

The light still remained, for which both boys felt glad. It afforded
Jack a goal which he was striving to gain; and it told Tom further down
that the inmate of the upper room was awake and still moving about,
though her sobs had ceased.

Once Tom fancied he heard something stirring back of the house. He hoped
it might not prove to be a servant attached to the Potzfeldt place or an
attendant who had charge of the pigeon loft.

Jack was almost up now. He had only to cover another yard of space when
he could look into the room of the lighted window. That was where fresh
peril must lie, because his figure would be outlined in silhouette, and
any one moving about the grounds might discover that uninvited guests
had arrived.

Tom wished he had told his chum to insist that the light be immediately
extinguished, if, as they believed, it proved to be Bessie who occupied
that room. He hoped his chum would think of it without being told.

There! At last Jack had arrived, and without accident! Now he was
cautiously thrusting his head up a little, to peer within.

Tom held his breath. So much depended on what would follow Jack's
betrayal of his presence.

"Tell her to put out the light, first of all, Jack!" Tom gently called
out, using both hands as a megaphone to carry the sounds.

It seemed that he must have been heard, and his directions understood,
for immediately there was another movement above, after which the
illumination ceased, as though Bessie had blown out the lamp.

Tom breathed easier, though he still continued to look, and wonder how
his chum was going to get the girl safely down from her elevated
apartment. Jack was not so fertile in expedients as his chum, and many
times depended on Tom to suggest ways and means.

While Tom was still waiting, and hoping for the best, he heard his
comrade whisper down to him as he hung suspended, clutching the sill of
the open window.

"After all, you'll have to come up too, Tom," he was saying feverishly.
"There are complications that'll need your judgment, knots to untangle
that are beyond me."




CHAPTER XXI

IN THE OLD LORRAINE CHÂTEAU


What Jack said in his cautious fashion puzzled Tom. For the life of him
he could not understand what had arisen, calling for any unusual display
of generalship. Surely Jack should have been equal to the task of
getting Bessie down from the window, even if he had to make use of
knotted bed-clothes in lieu of a rope.

Still he had asked Tom to come up, and there was nothing to do but grant
his request. "Complications," Jack said, had arisen. That was a
suggestive word, and to Tom's mind seemed to hint at further mystery.

Accordingly he proceeded to imitate the example of his comrade. Jack had
shown the way, and all his chum had to do was to follow. As Tom was also
an all-around athlete, accustomed to much climbing from small boyhood,
after nuts and birds' nests and all such things as take lads into tall
trees, he found but little trouble in making the ascent.

When he drew himself alongside Jack, the other gave a sigh of relief.

"Whee! I'm glad you've come, I tell you, Tom," he said. "It was getting
too big a job for me to tackle."

"What's happened, Jack?" asked the late arrival on the stone ledge under
the window of the upper room.

"First, here's Bessie, Tom," Jack went on. "She wants to shake hands
with you. Since we parted, when the steamer was docked, the poor girl
has been having all sorts of trouble; and she's glad as can be to see us
both again; aren't you, Bessie?"

Tom, feeling a small, trembling hand groping for his, immediately
grasped it, and gave a squeeze that must have carried conviction to the
heart of the girl.

"Oh, I'm shivering like everything!" she murmured, adding quickly: "But
not with fear. It's because my prayers have been answered, and help has
come at last, when everything looked so awfully dark--and I'm so very,
very hungry."

"Hungry!" repeated Tom, starting, it seemed such a very strange word for
the girl to use, even though they were in Germany, where all food he
knew must be getting exceedingly scarce.

"Yes, what do you think, that rotten bounder of a spy is half starving
the poor girl! He ought to be tarred and feathered, that's what!"
growled the indignant Jack.

"Not so loud," warned Tom. "Some one may hear you, Jack. But tell me
what you've learned."

"Why, first of all, Tom, it was Bessie who wrote that warning message I
had, and attached it to that little balloon, hoping the favorable breeze
would carry it over the front to the French lines. So that mystery is
explained. Then, Tom, there are _two_ we've got to take out of this
place, instead of just one, as we thought."

"I don't get you!" Tom ejaculated. "What do you mean by two?"

"It's a story in itself, I guess," whispered Jack. "I don't wholly
understand it myself. But it seems that Bessie's mother didn't drown
after all when the _Lusitania_ went down, as Potzfeldt reported she
did."

"You surprise me, Jack! How could that be?" demanded the other youth,
thrilled by the startling information.

"Oh, that slick rascal managed it somehow," came the soft if indignant
reply. "We'll learn more about it later on. He was picked up by a
fishing boat. The lady was temporarily out of her mind, so he gave it
out later that she had gone down. How he ever got her over here in
Germany beats me. But he managed to do it it seems. And she's been kept
a prisoner in this old château of his ever since!"

"But what was his object?" asked the amazed Tom.

"It had a heap to do with finances," Jack told him. "While he held a
paper that gave him charge over her daughter over in America, and a part
of the big Gleason fortune also, there were valuable papers he had been
unable to get his greedy hands on. She absolutely refused to tell him
where they were hidden. As a last resort what did the wretch do but go
all the way back to America."

"You mean to fetch his ward across with him, Jack?"

"Yes, just to use Bessie as a lever to compel her mother to give up
those valuable papers. I always said, you remember, Tom, that man was
hugging some secret to his heart. And so he was."

"He's been treating Bessie badly then, half starving her, I think you
said?" continued Tom.

"Just what he has, poor girl," growled his chum, savagely. "It's an
awful thing to be hungry! I don't see how any one can stand it. But he
hasn't broken the spirit of either of them yet, though Bessie's getting
so weak she finds herself crying every now and then, just as we heard
her. And it was that which brought us over to find out what it meant.
But Tom, tell her we mean to stand by, and see that both her mother and
herself are taken to a place of safety."

This Tom readily did, though as yet he could hardly understand just how
their promise could be fulfilled. One they might manage to take aloft
with them, by crowding, but the Caudron was not capable of seating four;
nor would it be safe to carry a couple of inexperienced passengers along
with themselves.

"But we're losing valuable time," he observed. "The sooner we get in
touch with Mrs. Gleason the better. There's a whole lot to be done
before we can say we're on the safe side of the fence."

"Then first of all we'd better climb inside the room, hadn't we?"
suggested Jack.

In answer Tom proceeded to get one leg over the sill, and then pass his
entire body across. Jack quickly followed. In the semi-darkness, for the
moon gave a dim light, they clustered there, and continued to map out
their immediate plans in whispers that could not have been heard a dozen
feet distant.

It appeared that Bessie knew where her mother was confined, though both
doors were fastened on the outside to prevent their having
communication. But the girl had found a way. Night after night she was
accustomed to slipping from her window, when everything was quiet below
and the lights all out, making her way along that narrow coping, or
ledge, and tapping softly at the window of her mother's room.

They would remain together until toward morning, when the girl made it a
practice to return by the same perilous route.

On this particular night it had seemed as though the lights below would
never go out. Carl Potzfeldt, the master spy, expecting important news
and a messenger from the headquarters of the Crown Prince, had been
waiting up until long after midnight in order to fullfil the important
duties entrusted to him.

Jack suggested that he creep along that coping and inform the lady of
the golden chance for escape that had arrived. But as she would hardly
be able to return by the same way, it seemed as though some other scheme
must be considered.

Bessie herself had a brilliant thought bordering on an inspiration.

"Listen, and I will tell you," she said at this juncture. "All the time
I have been here my one thought has been of escape. I dreamed nothing
else save getting my poor mother away from the clutches of that coward
who had hypnotized her in the past, and made her believe he was a good
man as well as her cousin from Alsace-Lorraine. And I know of a way it
can be done."

"Tell us your plan, please," begged Jack; though he would be sorry to
learn that the honor of releasing Bessie's imprisoned mother was not to
fall to his share in the undertaking.

"There is another window. It opens upon a hallway; and I can get through
it, because I've tried it more than once. But the proper time hadn't
come, for how were we to flee from this awful country? Wait for me here,
both of you. I shall be able to open her barred door, and then my own.
And it is better that I carry her the good news than some one who would
be a stranger to my mother, however much I have told her about you."

Tom saw that her plan was the best, after all. He himself had been a
little afraid that if Jack came tapping at the window of Mrs. Gleason's
room she might take the alarm, thinking it but another twist to the
odious schemes of Potzfeldt, and perhaps shrieking out in terror, which
would cause an alarm, and ruin everything.

Bessie climbed nimbly out of the window, showing how accustomed she was
to such athletic exercises. Jack held on to her to the last, and his
whispers were all of an entreating character, as he begged her to be
very careful, and not slip in her excitement.

Now she was gone, and the two air service boys, left by themselves in
that room of the old Lorraine château, counted the seconds and the
minutes until they should hear a gentle signal at the door, to signify
that Bessie and her mother were there, about to enter.

Jack walked softly up and down, like a velvet-footed tiger in its cage.
He was so worked up by the excitement of the occasion that Tom did not
have the heart to ask him to stop his movements, though he certainly
would have done so had not the other been keeping on his tiptoes all the
while.

What a remarkable turn their venture into the country back of the
enemy's lines had taken! And what astounding discoveries they had made
in the bargain!

Jack was getting more and more impatient. Several times did he pause at
the door, to lay his ear close to the heavy panel, and listen. He
wondered what could be keeping Bessie. Surely she had had ample time to
open the door of her mother's room and explain everything to the lady.
In his excitement he pictured all sorts of fresh trouble as having
befallen the girl. What if by accident she had run across the master
German spy in the corridor? But then, in such a case, Bessie surely
would have screamed in order to warn her two friends that they were in
danger of being discovered, should Potzfeldt and some of his assistants
burst into the room.

Of course Jack had magnified things wonderfully. Less than half the time
had elapsed than he thought had passed when there came a soft scratching
on the door to notify them Bessie was there. They next heard a slight
creaking sound, and then the soft closing of the door.

"Bessie, is it you?" asked the eager Jack, softly.

A reply in the affirmative followed.

"And here is mother with me," added the girl, a note of joy in her
voice, even though she spoke in a whisper.

So they came together. In the semi-darkness the boys could not see what
Bessie's mother looked like. They did note, however, that she was small
of stature; and this fact pleased Tom very much indeed. For already he
had figured out just how the rescue must be carried out, since there
seemed to be no other way.

His plans would entail some sacrifice on Jack's part, and also more or
less exposure to peril; but then Tom knew his chum too well to imagine
he would hesitate even a moment when called upon to take this additional
burden on his shoulders.

Both of them squeezed the trembling hand of the woman, and as best they
were able assured her that they meant to carry both Bessie and herself
to a place of safety, provided they were courageous enough to trust
themselves to the care of two air pilots.




CHAPTER XXII

FACING MORE DIFFICULTIES


"As for me," spoke up Bessie, immediately, just as Jack felt positive
she would, "I'd like nothing better. I've been up once in a
hydro-airplane, and would have gone many times if mother had allowed
me."

The lady did not seem to anticipate having a very delightful time of it,
for Tom felt her shudder; but she was courageous, and evidently ready to
attempt any hazard in order to gain her freedom.

"If only there is some way to fasten me securely," she told them, "I am
willing to do anything you say, my brave boys. So make your plans
without regard to my feelings in the matter."

Jack about this time evidently began to scent something with regard to
Tom's intuitions; at least his word implied a growing skepticism
concerning their ability to find room for two passengers aboard a plane
intended only for a pilot and an observer, or a gunner.

"Of course one could squeeze in alongside me, Tom," he mentioned
hesitatingly; "but do you think it's wise to have anybody with you?
Mightn't it interfere with the working of the controls, and add to the
danger?"

"It certainly would, Jack; and that's why I'm forced to call on you to
make a sacrifice."

"Go on and say what's on your mind, then," demanded Jack. "No matter
what it's going to be, you'll find me ready and willing for anything."

"You'll have to wait for the second trip," Tom announced.

"All right, just as you say, Tom. When will that be, later on to-night?"

"If it's possible to get back, yes," said the other.

"But if you can't make it, then to-morrow night, Tom?"

Jack was not overcome with fear, even though the prospect did appear
anything but cheerful. Bessie listened to this low talk, and gave
evidence of growing anxiety.

"But why should this be necessary?" she put in at that juncture. "I can
stay behind just as well as not. Then perhaps another night later on you
could come again, and take me with you to the French lines, and safety."

Jack sniffed in disdain.

"Well, I guess not, Bessie!" he told her, almost sternly. "I'd just like
to see myself sailing away, and leaving you here to stand the racket.
No, both of you are going to accompany Tom. I can find a hiding place
somewhere around; and besides, no one will suspect that an American
flier is hanging out here. There's only one thing I hate like everything
to think of."

"And I can guess what that is," Tom said, quickly. "You dread to
contemplate a long eatless day before you. That's the worst punishment
anyone could hand out to you, Jack."

"As far as that goes," interrupted Bessie; "I can tell Jack where the
pantry window lies. As the catch is broken you can easily climb in
through it later on to-night, and lay in a supply of food. There is
always something there. Before that bad man shut me up he tried to
starve me, and I stole food myself. Then he guessed what was happening,
for he fastened my door, and only allowed me to walk in the grounds in
company with a woman he has for a housekeeper."

Thereupon Bessie gave Jack minute directions how to find the window
leading into the storeroom. Thus armed the young aviator felt that he
ought to be able to stand it, in case his comrade found it impracticable
to return on the same night.

"Since all that is fixed," remarked Tom, "it strikes me we had better
get out of this place quickly. Can you lead us down by way of the
stairs, Bessie?"

"Oh, yes; for I know every foot of the way," she told him without
hesitation. "You see, I expected that some time we would have to slip
away by stealth; and so I made myself familiar with everything, even to
the fastenings of the great front door, with its chain and catch."

"Then we're in great luck," Jack observed, while Tom on his part went on
to ask further.

"All seems dark outside now, Bessie; would that indicate your jailer has
gone to his bed? And do you happen to know where his apartment is? That
might mean a whole lot to us, you understand."

"I don't believe he ever does really go to bed," she replied. "Once I
heard him complain that there were so many times during the night that
messengers came from headquarters with demands, or after information
expected from over the lines, that he had to secure his sleep while
fully dressed, and by throwing himself down on a Turkish lounge he has
in his room."

"Well, so long as his sleep is sound it's little we care how or when he
gets it," announced Jack, flippantly. "And when you give the word, Tom,
we'll all be ready to follow Bessie down the stairs."

Tom was even opening his mouth to say there was really nothing to detain
them, if Bessie and her mother had secured what trifles they wished to
take away, but after all he did not speak the words that were on his
lips.

Through the open window they suddenly heard the sound of heavy, guttural
voices. They seemed to come from the road near the entrance gates.

Tom stepped over to the window and looked out. What he saw gave him an
unpleasant feeling. There were lights already on the crooked driveway,
and a number of men seemed to be advancing in a group.

Jack at his elbow was also staring, and grinding his teeth with anger.

"Hang the luck, I say!" he gritted. "That fresh bunch of Boche officers
is bound to knock our plans silly. They'll stir things up again, and we
can't get away. Then perhaps some one will discover the doors of the two
rooms are unfastened, and that'll start a hornet's nest about our ears."

"Get down, and keep hidden, Jack," urged his companion. "They have
lights with them, and might see us as they come along. There's a
general, at least, in the lot, that big stout man in the center, and I
imagine those other officers belong to his staff."

"But what are they walking for?" whispered Jack, incredulously. "German
officers in the High Command don't often tramp along the roads like
that, do they?"

"They may have broken down in their car; and learning they were close to
this house have come on here to wait till repairs are made. Lots of them
know Potzfeldt, I suppose, and one of these men may have been here
before on business. The worst of it all is we'll have to give up our
scheme of going down by way of the stairs."

They crouched down and watched as best they could, while the half-dozen
men in the gray-green uniforms of German officers, and with many
decorations on the breast of the martial-looking commander, approached
the château's front door.

Already lights had sprung up on the lower floor. Undoubtedly Potzfeldt
had heard his unexpected guests coming, and was bestirring himself to
welcome them, though inwardly raving over having his rest so frequently
disturbed.

He met them at the door, and there ensued more or less talking, all of
it in the choicest of German. Again Jack felt sorry that his education
was so incomplete that he could only guess at what most of it meant.

Still, Tom could pick up a little of what was said. There was certainly
mention made of an unfortunate accident to a car, that would necessitate
a delay of some hours for repairs, possibly until morning. The general
did not altogether fancy sitting in the car for hours in the cool night
air. Especially was this the case after he had learned that there was a
house half a mile or so further on where food and drink could be
obtained in plenty, if only they chose to walk that far.

All of the newcomers had by now stalked inside the house, and the coast
seemed to be clear, so far as those above could see. But down below
there was much hurrying to and fro, which would indicate that Potzfeldt
must have aroused his retainers, and they were running up and down from
wine-cellar to dining-room, bearing acceptable refreshments for the
unbidden guests.

"Say, I wonder if that old stout chap could be Hindenburg himself?" Jack
whispered in his chum's ear. "I noticed that Mr. Potzfeldt seemed mighty
obsequious, as if he felt highly honored at having such a noble visitor,
and nothing could be too good to set before him."

"Well, I wouldn't be surprised if you'd hit the nail on the head when
you said that, Jack," the other told him. "He was a big, burly man, with
a mighty important air about him; and he wore a mustache such as we've
always seen in pictures of Hindenburg. But no matter, it doesn't concern
us at all, if we can find a way to get down from here."

"Only," said Jack, whimsically, "I do hope if they've got their German
appetites along, they don't clean out that pantry before I get my
look-in, that's all. Twenty-four hours without a single bite would be
the limit for me. I don't think I'd survive the ordeal. Now what, Tom?"

Tom was looking out again.

"That's lucky," Jack heard him mutter.

"Of course it is. But tell me what you're referring to, Tom."

"Some clouds have come along. One is right now covering the face of the
moon, you notice. Well, if we are forced to lower Bessie and her mother
from the window by means of a rope made from knotted bed-sheets, we
stand a chance to avoid being discovered at work by any one who might
happen to be abroad just then."

Jack chuckled as though pleased.

"Sure, that's the game, Tom! I knew you'd be equal to getting up some
sort of clever scheme. And I'll start in right away making that rope. We
want to be certain it's strong enough to bear their weight, that's all."

"I'll help you at the job," Tom told him, for he too wished to be
positive about the twisted parts of the sheets, before trusting the girl
and her mother to their care.

Fortunately they found that Carl Potzfeldt had some of the airs of a
millionaire about him. The sheets were of stout linen, instead of the
customary cotton to which the American boys were accustomed. When these
were cut first with a sharp pocket-knife, and then torn into long strips
about a foot or so in width, they could be twisted and knotted until the
result was a novel rope of at least twenty feet in length.

Neither Bessie nor her mother said a single word. They seemed more than
willing to be thus lowered to the ground. Such a novel experience might
not be delightful, but it amounted to very little when compared with
what they had suffered at the hands of their rude and cruel captor.

Soon the odd rope was ready for use.

"Let me be the first to go down," Bessie then said to Tom, in an
authoritative voice.

As he had been about to propose the same thing he made not the least
objection, but proceeded to secure one end of the strange rope around
her body just below the arms, Bessie herself assisting in the operation.

Before attempting the task, Tom stood at the window listening for some
little time. He wished to make sure that none of the German officers had
remained outside. Tom also meant to satisfy himself that there was no
lurking form among the bushes on that side of the château, since the
light streaming from the lower windows dissipated some of the advantages
gained by the temporary clouding of the moon.




CHAPTER XXIII

LEFT BEHIND IN THE ENEMY'S COUNTRY


Tom appeared finally to be satisfied, for he turned around to Bessie.

"Now if you're ready we'll lower you safely," he told her.

The girl showed considerable nimbleness in climbing over the
window-sill. Jack insisted in having a hand in dropping her slowly down.
It was not far, and in a few breaths the girl had reached the solid,
ground. She understood what was expected of her, and immediately cast
off the rude rope, so it might be drawn up and made to serve once more.

Mrs. Gleason showed just as much bravery as her daughter, and was also
lowered without trouble.

"You go down next, Tom," whispered Jack. "Then I'll draw it up, and can
join you easily enough without the help of the rope. A white thing like
this dangling here would be sure to attract attention, if any one came
around the corner of the house, and might cost us dearly in the end."

Tom understood. He preferred being the last to stay, but since Jack had
taken that upon himself, and was moreover adept at scaling walls, it was
folly to dispute his right.

So down Tom went. He had hardly landed when the sheet-rope was swiftly
drawn up, and vanished within the room. After that Jack was seen making
his way down over the same route he had taken while ascending.

Soon they were all together again, and their queer exit from the room
seemed not to have been discovered, for which they felt very thankful
indeed.

Tom led the way into the friendly bushes close by. It was his intention
to skirt the carriage-drive, as it might contain elements of danger for
them. Once they had passed out on the main road to Metz, it would not
take them long to reach the field where the big Caudron airplane lay
like an exhausted and enormous bat, awaiting their coming to spring into
activity.

In passing along they were enabled to catch a glimpse of the interior of
the dining-room where Carl Potzfeldt was entertaining his distinguished
visitor to the best of his ability in those times when scarcity ruled.

Tom managed to get a better look at the general. He was more than ever
convinced that the big man with the strong features and all these
decorations on his uniform, was in fact Hindenburg, the head of the
whole German army, whose opinion carried even more weight with the
people just then than that of Kaiser Wilhelm.

It would be something worth while to be able to say they had been within
a dozen feet of the famous commander, the Iron Man of Germany. Tom
vaguely wished he had some means of capturing the general then and
there, and carrying him over the lines to the French headquarters. That
would indeed be a feat well worth praise from General Petain; but of
course it was utterly impossible.

They gained the gate, and there Tom insisted on looking carefully around
so as to make doubly certain that no sentinel had been left on duty
while General Hindenburg remained within the house.

When this fact was made clear he led the way forth. The little party of
four almost ran along the road, so eager were they to place as much
ground as possible between themselves and the seat of danger.

There was always a chance that the flight of Bessie and her mother might
be discovered by some one connected with the household, and communicated
to Potzfeldt. He, of course, would exhaust every means in trying to
overtake the fugitives.

But Tom chuckled while telling himself that they must needs have
extraordinary and fleet steeds who could successfully pursue those who
had trusted their safety to his care and that of the big Caudron
airplane.

Jack hardly knew where the field lay, having become "rattled," as he
called it, from the adventures at the château. So after all it was
fortunate that Tom had taken his bearings as well as he had. He knew
just when to leave the road, and start across the open space. Then the
lone tree began to loom up, for the moon had once more thrust her face
from behind the enveloping cloud.

"It's all right, Bessie," said Jack reassuringly. "Our plane lies close
to the foot of that tree ahead there. If all goes well you'll be on your
way before many minutes have passed."

"Thanks to you, Jack," murmured the girl admiringly.

"Shucks! that isn't a circumstance to what I'd be willing to do for you
and your mother!" Jack boldly told her.

"But all the same it is very brave of you, Jack, and I can never forget
your kindness to us," she insisted. "I hope and pray that nothing
terrible will happen to you while we're gone, and that I'll soon see you
again."

"I hope so too, Bessie," he chuckled, as if amused. "As to anything
happening to me, I guess I know how to hide all right. The worst that
can knock me is getting a little mite hungry, you know. If that big
German general and his staff leave a bite in the pantry I'm going after
it, believe me! Then I'll find a hole, and crawl in, somewhere close by
here, so I can watch for Tom's return."

Apparently Jack had mapped his whole programme out; and it seemed that
an adequate supply of provisions occupied the most prominent place in
them.

They were now at the spot where the Caudron had been left. Tom's mind
was eased of the secret fears he had entertained when he saw the machine
was still where they had left it. So far as he could tell no one had
been near to meddle with it.

First of all Bessie and her mother must be fastened securely to the seat
where Jack had sat on the trip to Metz. Tom, like a wise general, had
provided himself with plenty of the strips of linen from the torn
sheets. This he utilized in tying the passengers, so that there would
not be the slightest chance of their falling out.

Even if Mrs. Gleason should faint through terror on finding herself a
mile up in the air, she could not fall out of the machine. But Tom
entertained high hopes that both of his passengers were going to display
extraordinary courage, and give him no cause at all for anxiety.

Jack tried to assist in the operation, but his hands were trembling so
with the excitement that Tom pushed him away.

"Leave the job to me, Jack," he told the other. "Too many cooks spoil
the broth, you know. I'll make everything secure, depend on it."

"Of course I know you will, Tom," the other hastened to assure him.
"Perhaps it is better only one handled the business. And Bessie--"

"Yes, Jack," said the girl, slipping a hand out toward him, which Jack
took in his, and pressed reassuringly.

"Don't bother your head for a single minute about me, mind. I'll be all
right, and perhaps able to join you again this very night. It's a great
lark for me, and I wouldn't miss it for a heap. But oh, if only we could
kidnap that big commander, and carry him over to have an interview with
General Petain, how proud I'd be!"

Tom smiled on realizing that the same idea had occurred to Jack that had
flashed through his own mind.

"Here, take my automatic, Jack," Tom said. "You may find occasion to use
it before I come back."

The other complied, and apparently he felt more confidence, once he knew
he had in his possession the means for defending himself should any
ordinary danger threaten. Tom was loath to depart, once he had
everything arranged. The truth of the matter was he hated to leave his
chum in the enemy country; it seemed as though he were deserting him.

So he "fiddled" around, testing this wire guy, and using his electric
hand torch to give him light, so he could once more run his eye over the
motor on which he had been working.

"Come, Tom, it's no use hanging around here a minute longer," Jack had
finally to tell him. "Get aboard and I'll spin your wheel for you and
give you a boost for a start. Then I'll drop out of sight, because some
of them may run this way when they hear the clatter and guess the
cause."

Tom climbed to his seat and settled himself according to his customary
thorough manner. He tried the controls, and was not satisfied until he
had tested everything within reach.

"Say when, Tom!" Jack remarked, having finally left Bessie's side and
gone to the propellers of the big plane.

Tom drew in a long breath. He knew he had a risky venture ahead, taking
those two inexperienced passengers over the hostile lines, possibly
amidst showers of exploding shrapnel shells. But it was not this that
weighed so heavily on his spirits. He felt almost like a criminal at
leaving Jack behind.

"All right; let her go!" he announced grimly.

There came a sudden whirring sound. Then the loud hum of the motors
chimed in, and the big Caudron machine started off.

"Good-bye, Tom! Good-bye, Bessie!" Jack was heard saying, although the
noise of the plane almost drowned his voice.

Faster they went now, as the machine gained momentum. Tom paid strict
attention to his business of pilot. At just the proper time he must
elevate the forward rudder which would cause the plane to leave the
ground and start upward at a sharp angle.

Jack stood gazing after the object that was quickly growing more and
more indistinct in the dim moonlight, gazing with a strange heaviness in
the region of his heart. He had to shut his teeth firmly together to
conquer the momentary weakness that threatened to overpower him. But his
resolution remained master of the field.

"If only he gets them safely across," Jack muttered to himself, when he
could no longer see the airplane, though its noisy working came plainly
to his ears, "it'll be all right. But they've heard the racket over at
the house, too, I guess, because men are shouting, and I can see lights
flashing this way and that."

When he discovered that men with lanterns were actually looking around
as if to learn where the departing airplane could have been resting, and
what it all meant, Jack concluded it was time to conceal himself.




CHAPTER XXIV

TROUBLOUS TIMES FOR JACK


The men bearing the lanterns came closer, Jack saw, as he himself
scurried amidst the bushes seeking a hiding-place.

"Guess that Potzfeldt must know that planes can drop down on his big
open field," the youth muttered to himself. Then as a new idea flashed
through his brain he continued: "Whee! I warrant you now that ours
wasn't the first airplane to land there. Sometimes maybe the spy he
wants to send back of the French lines gets aboard right here, with his
little cage of homers."

Presently loud exclamations told that the men had discovered the marks
of the arriving and departing Caudron machine. Jack could hear them
exchanging remarks about it, in German of course. Then he saw one of the
trio start back toward the house. He was half running, as though much
excited. Jack jumped to a conclusion.

"Say," he said to himself, in a whisper, as though even the sound of his
own voice might be company for him, "now that must have been Carl
Potzfeldt himself. What's he making for the house with a hop, skip and
jump for? Perhaps one of his sharp-eyed men has told him there are marks
of small shoes around; and old Carl got a sudden suspicion something
tremendous has happened."

The master-spy came back again. He was now accompanied by two others,
and Jack saw by their uniforms that they were members of the general's
staff.

All were talking earnestly, Potzfeldt, Jack imagined, telling them some
story concerning Bessie and her mother, in which he figured as a noble
man, trying to save Mrs. Gleason from the wiles of some American fortune
hunter, into whose hands he now feared she and her daughter had fallen.

"My! but he's wild!" chuckled the hidden observer. "He realizes that the
two American boys have been too much for his scheming after all. Guess
he must have had a suspicion all along we'd break up his game. That'd
account for his plotting with the other spy to have our planes meddled
with, so we'd meet with some terrible accident that would remove us from
his path."

Jack was really enjoying himself. It did him good to hear Potzfeldt
raging around, and spluttering as though his rage half choked him.

What Bessie had said concerning the cruel treatment she had received at
the hands of her mother's relative had fired Jack's blood. He detested a
man who in order to accumulate money could treat a helpless woman and
girl as Potzfeldt had those who were in his power.

"I'd just like," he was telling himself as he listened, "to be one of
three fellows who had that villain in their power, with a nice big
kettle of hot tar handy, ditto three feather pillows. Oh, wouldn't we
make him a queer bird, though! The extinct dodo'd have nothing on him,
believe me! But it's fine to hear him raging around like that. I only
wish Bessie could listen."

After a time Potzfeldt and his men went away. They knew they could do
nothing, as the big enemy plane had long since departed, and must by
then be many miles on the return journey to the French lines.

An hour went by and all seemed quiet in the region of the big house by
the side of the road. Jack had not forgotten the promise made to
himself. It might mean additional danger, to be sure; but when he
thought of a long day ahead, in all probability, with an empty stomach
constantly reproaching him, he felt equal to the task.

He had no trouble in finding the entrance to the grounds. Everything
seemed quiet, as though the general and his staff were endeavoring to
get a little sleep before resuming their journey to the fighting front.

Jack was soon under the window that had been described to him by Bessie.
It gave light to the pantry during the daytime. Also he had been
assured, the catch that secured it was broken, so that if he were bold
enough he could easily gain entrance and take his pick of what the
housekeeper had stored there.

Such a nimble chap as Jack had no difficulty whatever in making an
entrance. Finding himself within the big closet, he listened, and,
hearing no sound, struck a match.

By the light thus afforded he could see what lay within his reach. Trust
one with an empty stomach for knowing what he wants under such
conditions. Jack immediately commenced to gather together a supply of
food of various kinds, such as could be eaten without need for a fire.

Quantity rather than quality seemed to rule his actions. At any rate,
when he gathered his spoils together he had quite enough to last an
ordinary man several days.

"Well," he told himself, when lifting the bundle he had made. "I may be
marooned around here a long time, and never get another chance at this
supply station. I believe in striking while the iron's hot. Now to get
it outside without raising a crowd."

It was indeed a lucky thing that there was no watch-dog at the Potzfeldt
place. Undoubtedly this was because of the many visitors coming and
going at all times, who might be bothered by a savage beast.

Jack managed to get back safely to the nest where he had hidden at the
time of the excitement, when Potzfeldt and his men were in the field. He
gave a sigh of relief after it was all over.

Soon the young aviator settled down to try to get some sleep, as some
time still remained before dawn would break. He meant to be early astir.
There was danger in the air, as he might be discovered unless he
arranged for a better hiding place than the covert of bushes where he
now lay.

Whether his sleep was worth while, or rendered uneasy by dreams, Jack
never told. He was awake though, when the sun peeped above the horizon,
and began to bestir himself. Presently people would be moving about.
Some of the men might even come out to the open field again, to look at
the telltale marks. And if they chanced to suspect that one of the crew
of the Caudron had been left behind, a hasty search was apt to reveal
his presence.

Accordingly Jack commenced to retire deeper into the wood, and managed
by great care to cover his tracks fairly well in so doing. Finally he
found a place that seemed to him about as good as anything he might
expect to run across; and so he crawled into the bushes again.

Then he had a most pleasing task to start upon, which was nothing more
nor less than that of appeasing his appetite, never more voracious, he
fancied, than just then. Without a twinge of conscience regarding the
fact that it was stolen food he disposed of, Jack commenced his morning
meal.

"I'm only enjoying some of the good stuff that scoundrel deprived Bessie
of," he told himself, with a grin of contentment, after he had eaten
until he could not take another bite. "Besides, everything is fair in
war-times. When you're raiding through the enemy's country it's supposed
you'll live on the spoils around you. Well, I'm going to live, and Carl
Potzfeldt is my enemy, all right. He's proved that in a dozen different
ways."

That idea set him to thinking about Bessie again, how she had taken such
a queer way to try to warn him, after overhearing her guardian plotting
with one of his men the injury to one or both of the young Americans.

"Now I wonder," Jack mused, as he lay in perfect peace with the world,
for he had eaten his fill, "how he knew we had joined the Lafayette
Escadrille. But then those German spies learn a lot of things, and he
may have been keeping tabs on Tom and me right along. Deep down in his
heart he suspected we'd bother him, and so he wanted to get us before we
had a chance to strike. Well, the shoe is on the other foot, it seems."

The morning advanced. Fortunately it proved to be a fair day for so
early in April. Had a storm arisen Jack might have found it hard to find
shelter. As it was, all he had to do was to lie under the bushes and
doze from time to time.

Whenever he got to thinking of Tom a queer feeling came over him. It
made him uneasy, though he could not explain why that should be so; and
from time to time he took himself to task for being worried.

"Of course Tom got back safe and sound," he would muse. "He's too clever
a pilot to make a bad job of such a business. And yet, if he doesn't
come to-night I'll be terribly anxious. Oh, forget all that! will you,
Jack Parmly? Think of something pleasant now. For instance, that it's
nearly high noon, and most folks lunch then."

He had just calmed down again, when he had a sudden chill. Men were
working in a field about three hundred yards away, for he could hear
them calling to one another in German.

Suddenly there came a series of snappy barks. Jack looking around was
horrified to discover a small dog. It was a dachschund, long of body,
and with crooked, bandy legs. It was standing before the hidden boy and
evidently bent on telling everybody by his barks that some suspicious
person was hiding in the bushes.

It was a crisis that made Jack's blood run cold!




CHAPTER XXV

BACK TO SAFETY--CONCLUSION


Jack hardly knew what to do. He made threatening gestures at the dog,
but they, of course, only added to the trouble, for the animal renewed
his barking more briskly than ever.

Then Jack had an inspiration, such as sometimes comes when all seems
lost. If the dog continued his barking, sooner or later one of the men
working in the field not far off would have his curiosity aroused, and
come to ascertain what sort of wild animal the dog had treed.

Jack unfastened his package of food. Since stern tactics had no effect
he meant to try to make friends with the dachschund. Dogs are always
more or less hungry, he argued; and this must be especially true at that
time in every part of Germany, Alsace-Lorraine not excepted, since the
pinch of two-and-a-half years of war had made terrible inroads on all
kinds of food.

Jack commenced to eat. The dog kept on barking, though not quite so
savagely now. The smell of the food had reached him, and he would
occasionally give a little imploring whine between his barks.

So Jack spoke to him in a soft, wheedling tone. Then he held up a scrap
of meat, and caught the eager attention of the little beast; after which
he tossed it to him. It vanished like a flash. The dog even wagged his
tail, as if to let the man know his animosity was quickly giving way to
interest. Surely any one who had all that food along with him could not
be a suspicious personage.

The next scrap fell a little short, and the dog advanced to get it. So
by degrees Jack tempted him, until in the end he was patting the squatty
animal on the back, and still feeding him. They were now the best of
friends. Kindness had accomplished what all the threatening gestures,
supplemented with many sticks hurled at the beast, could never have
brought about.

Jack believed he had saved himself from discovery. He could easily
understand what hardships must have awaited him had he ever fallen into
the hands of Carl Potzfeldt.

The afternoon went by very tediously. The dog came and went, staying for
short periods with Jack. The vast store of food was a magnet that held
the little beast fast. It had doubtless been a long time since he had
had his full.

By degrees the day waned, and evening came along.

Jack never saw the sun set with less regret than he did on that
occasion. Still he knew that long hours must pass before the moon would
peep in view above the eastern horizon.

As he sat, he allowed his thoughts to roam backward. Once more in
imagination he could see his friends who were on the other side of the
ocean. Then for a change he would take another "snack," as he called it,
for lack of anything else to occupy his attention.

Several times also he dozed, but always arousing with a start at some
sound, under the impression that it might be Tom who had come, and, not
finding him, gone away again.

Finally he began to believe it must surely be past midnight; and the
late moon would presently be making an appearance. On looking closely
toward the east he became aware that the heavens were betraying such a
fact, for a distinct silvery glow was beginning to appear, low down.

Then came a streak of light. It was the moon. Slowly she mounted higher,
as if more or less ashamed of the dilapidated appearance of her usually
smiling face.

Jack had earlier in the night changed his place of lodging. He again
occupied his former quarters close to the spot where he and Tom had
landed when they wished to overhaul the motor that was acting so badly.

The minutes dragged.

Then once more Jack bent his head, and put a hand up to his ear to
listen. He laughed to himself with glee.

"That's Tom coming!" he muttered joyously. "I knew Tom wouldn't fail me.
All the same I'll be mighty glad when I'm aboard the plane and on the
air route to Bar-le-Duc and my own cot."

Louder grew the sounds. There could not be the slightest doubt about it
now, Jack decided. A plane was coming at top speed, and keeping not a
great distance above the treetops of the little valley in which the
house of Carl Potzfeldt and the road to Metz lay.

Louder grew the insistent drumming. Jack wondered whether some of those
at the château might not also hear the racket, and, guessing what it
would mean, hasten out to the field in time to give Tom and himself a
volley of shots.

Now the plane was coming, like a great condor of the Andes about to
alight on a mountain peak. Jack gauged full well where it would land. He
ran with all his might to be close to the spot. The less time wasted in
getting him aboard the better for their safety, he believed, remembering
what cause Carl Potzfeldt now had for being suspicious when a plane
visited his meadow.

Then the big Caudron ran along the ground and came to a full stop.

"Jack!"

"Yes, Tom, I'm here, and mighty glad to see you!" cried the lad who had
counted the minutes until his brain seemed to reel with the strain.

"Get aboard in a hurry, Jack. We've no time to waste here."

"I know that even better than you do," returned the other.

There was indeed need of haste. The air service boys could hear voices
from where the château was located. Someone had heard the humming of the
oncoming airplane. It was Potzfeldt himself, and now he and two of his
men came hurrying out on the field, all armed with pistols.

Jack only waited to give the propellers a whirl, and then, as the motor
took up its work, he made a leap for his seat. Oh, how good it seemed to
be once more in that airplane!

"Stop! Stop!" roared a guttural voice in German. "Stop, or we fire!"

Now the airplane was moving along the ground, bumping and rocking
considerably. But Tom knew how to manage, and presently the plane
commenced to soar slowly upward.

Loud and angry voices announced the fact that Carl Potzfeldt had arrived
close enough to get a view of the rising plane in the misty light of the
moon.

"Stop! I command you! Stop!" roared the German. And then came the crack!
crack! crack! of firearms.

The air service boys, because of the noise of the motor, did not hear
the discharge of the pistols, but suddenly Jack heard the spatter of a
bullet as it struck the machine close beside him. Then he ducked and
made a motion to Tom to let his chum know that they were under fire.

But the machine was gaining headway rapidly, and presently they were so
high that those below could no longer reach them. Up and up they went
until they were thousands of feet above the valley that had been the
scene of this remarkable adventure.

Tom headed back along the course he had just come. It was now easy to
pick up one landmark after another, and in due course of time they
passed over the lines once more. Of course, the sound of the plane's
propellers was heard by the Germans, and some shrapnel was sent after
them; but as Tom was careful to keep high in the air, this did not reach
them, and soon they were out of the danger belt.

Fifteen minutes later they made a landing, this time on the well
remembered aviation field of Bar-le-Duc. Here there were attendants on
hand ready to care for the machines.

"Glad to see you got back," said one of the attendants, grinning. He
knew that Tom had gone off on the second trip to bring Jack.

The two air service boys found a car to take them to the villa. The long
ride through the night air had made both of them very sleepy, and yet
neither felt just then like retiring.

"It's a lucky thing, Tom," said Jack, between yawns, "that I had this
fur-lined pilot's coat along with me. Only for that I'd have been mighty
cold out there in the open last night, with no chance for a fire."

"Well, it's all past now, Jack. Tell me what happened to you during my
absence."

Jack, was nothing loath, and as quickly as possible gave his chum the
particulars of how he had gone into hiding and almost been betrayed by
the dog.

Tom had already told Jack about what had become of Mrs. Gleason and
Bessie. They had been taken to a house some miles back of the lines, and
were to be made comfortable there for the night.

"And early in the morning they are to start for Paris," Tom said with
satisfaction. "I managed through our captain to get them passage aboard
a train that is to take some wounded back to the base hospitals. Mrs.
Gleason says she means to stay in Paris and help all she can as a Red
Cross nurse, for she has had some experience in nursing."

"That's fine!" was Jack's comment. And then for the time being he became
somewhat silent.

Tom could easily understand that his chum was cherishing a hope that
some time or other when they were taking a vacation from their arduous
duties while flying for France, the pair of them might visit the French
metropolis, and if so they would certainly try to see Bessie and her
mother again.

"And I've got more news to tell," remarked Tom, when the pair were about
to turn in for their much-needed sleep. "You'll remember about that
message we found in the capsule on the leg of the homing pigeon. Well,
one of the other pigeons we found was used to send a false message to
the Germans, telling them that a certain part of the French line was
very weak. A short while later the Germans made a furious attack on that
part of the line, and, believe me, they caught it for fair--the plucky
French soldiers, aided by the artillery, literally wiped up the ground
with them."

"That's great news!" cried Jack. "Then it paid to bring down that
pigeon, didn't it?"

"It sure did, Jack!"

Two days later came a most important announcement, especially to the
American airmen.

"Things are coming our way at last," the valiant commander announced, as
they crowded about him. "The papers this morning say that Uncle Sam has
at last got his back up. Any day may now bring the glorious news from
across the Atlantic, telling that the United States has taken the steps
that will put her in this World War against the Central Powers. Then it
will be all over but the shouting."

"That's right!" cried Jack.

"You just leave it to Uncle Sam to do it!" added Tom.

Many more adventures were in store for the young aviators, and what some
of them were will be related in the next volume of this series, to be
entitled "Air Service Boys Over the Rhine; Or, Fighting Above the
Clouds."

And here for the present let us leave the air service boys and say
good-bye.

THE END




THE DICK HAMILTON SERIES

BY HOWARD R. GARIS

A NEW LINE OF CLEVER TALES FOR BOYS

DICK HAMILTON'S FORTUNE
  or The Stirring: Doings of a Millionaire's Son

Dick, the son of a millionaire, has a fortune left to him by his
mother. But before he can touch the bulk of this money it is stipulated
in his mother's will that he must do certain things, in order to prove
that he is worthy of possessing such a fortune. The doings of Dick and
his chums make the liveliest kind of reading.

DICK HAMILTON'S CADET DAYS
  or The Handicap of a Millionaire's Son

The hero, a very rich young man, is sent to a military academy to make
his way without the use of money. A fine picture of life at an
up-to-date military academy is given, with target shooting, broad-sword
exercise, trick riding, sham battles, and all. Dick proves himself a
hero in the best sense of the word.

DICK HAMILTON'S STEAM YACHT
  or A Young Millionaire and the Kidnappers

A series of adventures while yachting in which our hero's wealth plays
a part. Dick is marooned on an island, recovers his yacht and foils the
kidnappers. The wrong young man is spirited away, Dick gives chase and
there is a surprising rescue at sea.

DICK HAMILTON'S AIRSHIP
  or A Young Millionaire in the Clouds

This new book is just brimming over with hair-raising adventures of
Dick Hamilton in his new airship.

DICK HAMILTON'S TOURING CAR
  or A Young Millionaire's Race for Fortune

A series of thrilling adventures. Dick and his friends see the country
in a huge touring car. Their exciting trip across the country, how they
saved a young man's fortune and other exciting incidents are very
cleverly told.

DICK HAMILTON'S FOOTBALL TEAM
  or A Young Millionaire on the Gridiron

A thrilling story of how Dick made a real football team for his
school--the team that was laughed at by other military schools until
Dick took charge.




THE BOY-SCOUTS BANNER SERIES

By GEORGE A. WARREN

Author of the "Revolutionary Series"

The Boy Scouts movement has swept over our country like wildfire, and
is endorsed by our greatest men and leading educators. No author is
better qualified to write such a series as this than Professor Warren,
who has watched the movement closely since its inception in England
some years ago.

THE BANNER BOY SCOUTS
  or The Struggle for Leadership

This initial volume tells how the news of the scout movement reached
the boys and how they determined to act on it. They organized the Fox
Patrol, and some rivals organized another patrol. More patrols were
formed in neighboring towns and a prize was put up for the patrol
scoring the most points in a many-sided contest.

THE BANNER BOY SCOUTS ON A TOUR
  or The Mystery of Rattlesnake Mountain

This story begins with a mystery that is most unusual. There is a good
deal of fun and adventure, camping, fishing, and swimming, and the
young heroes more than once prove their worth.

THE BANNER BOY SCOUTS AFLOAT
  or The Secret of Cedar Island

Here is another tale of life in the open, of jolly times on river and
lake and around the camp fire, told by one who has camped out for many
years.


THE BANNER BOY SCOUTS SNOWBOUND
  or A Tour on Skates and Iceboats

The boys take a trip into the mountains, where they are caught in a big
snowstorm and are snowbound. A series of stirring adventures which will
hold the interest of every reader.