dn't know you knew how to run
one!"

"He is one of our very few qualified aviators," said the man who had
been on guard. "And every day now for weeks he has been coming here to
study the controls and all the details of this machine. It is in
perfect order, ready to take the air."

"And an Austrian monoplane! Why, we can fly over their lines!" exclaimed
Dick. "How splendid! But what are you to do, Steve?"

"You will soon know. Get aboard! Your seat is there. Strap him in,
Dmitri, while I see to the tank."

"Everything is right," said Dmitri. "But make sure for yourself--that is
a good rule."

In a minute Stepan was satisfied and had taken his place beside Dick.
Then the motor was started, the propeller began to turn, and in a few
moments they rose from the ground, soared above the trees, and were in
full flight.

"Now you see why we had to be warm!" said Stepan. "We are in for a long
flight. But up first! We must fly high!"

CHAPTER XVIII

THE FLIGHT

They rose higher and higher, climbing in spirals, until Dick had
completely lost his bearings. The night was cloudy, and there were no
stars to help him, and before long they had passed through the first
layer of low hanging clouds, so that he was denied the aid of lights and
towns below. Then when they had thus made it impossible for anyone below
to detect them, Stepan gave his motor full play and the real flight
began. Dick thought he had never in his life known a sensation so
glorious as this swift gliding along through the air. But he soon
appreciated the comfort that came from the thick clothes upon which his
chum had insisted. Despite the weight of the things, he was far from
being hot in that long night flight.

Sometimes he slept. He was aroused once when they descended, but the
country was wholly unfamiliar to him, and they were soon off again. But
with morning came a stunning surprise. The sun was visible now, and Dick
saw that they had been flying northeast! He had supposed that they would
head for the Servian army, but he guessed now, as he saw snow capped
mountains before them, that they had taken an entirely different course.
And his surprise was vastly increased when a strange sound assailed his
ears.

"Ah!" cried Stepan, exulting. "It is all right!"

Dick followed Stepan's pointing finger with his eyes, and now he saw the
source of the firing that had so astonished him. It was in front of him,
on the plain between them and the mounta