entered the enemy's lines in an effort to effect
their escape.

It was a daring adventure, but after a fight and chase, the four had
managed to seize the airship in which we now find them and had at last
fought their way clear. They had then held a council of war and decided
that it was best to head for the Balkans, rather than to run the gauntlet
of the Austrian flying craft which kept constant vigil in the direction
of the Italian lines.

Hal and Chester, typical American lads, were large and strong for their
ages, which were within a year of each other, seventeen and eighteen now.
In the rough lumber camps of the north, the two had had considerable
experience in the use of firearms and the art of self-defense--fists.
Also, during the school term each had practiced the use of the sword
until, though by no means experts, they could give a fair account of
themselves with this weapon--as each had done more than once.

Fortunately, both lads had made a study of languages and spoke French and
German fluently. They never had trouble on that score.

The great war up to this point had not gone as successfully as the
Entente Allies had hoped in the early days. The German lines on all
fronts were seemingly stronger than ever before. Even the entrance of
Italy into the war on the side of the Allies had failed to turn the
balance, as it had been confidently expected it would. East and west, the
German lines held, while in the Balkans the enemy was even now advancing
against the heroic little Serbian army, which, before many days, was to
be forced to relinquish its country to the iron heel of the invader.
Montenegro, the smallest factor in the war, still was fighting hard--the
rugged and gigantic mountaineers giving a good account of themselves upon
all sides.

This was the situation, then, as the airship containing Colonel Anderson,
British officer, Anthony Stubbs, American war correspondent, and Hal
Paine and Chester Crawford sped southward over Austria.

Several hours after the sinking of the Austrian aeroplane Chester spoke.

"Where do you suppose we are now, Hal?" he asked.

"I believe we must have crossed the frontier," replied Hal. "However,
we'll wait another half hour before descending to have a look."

The half hour up, Hal sent the airship lower and lower. Soon, a faint
gray speck below became visible, assuming larger and larger proportions,
until all aboard made out the ground beneath.

And then, half a mil