ere as eager as dogs
on the leash to be off and at the throat of the Huns. A wireless message
from Paris had come in soon after breakfast, stating that nearly a score
had been killed in the capital the previous night by fire from the
"Bertha."

"And it's up to us to avenge them!" exclaimed Jack.

"That is what we'll do if we have any luck!" added Tom grimly.

There was a last consultation of the officers, instructions were gone
over, and everything possible done to insure success. The moment a big
gun was sighted, the signal was to be given and the French long-range
cannon would open fire, while the bombing machines would also do their
part.

"All ready! Go!" called the major, and there was a rattle and a roar
that drowned his last word. The men of the air were off.

Led by Tom and Jack, the others followed. Up and up they arose, the
smaller planes flying high as a protection to the more cumbersome
machines of the bi-motored type. And soon the squadron, the largest that
had yet ascended from Camp Lincoln, was hovering over the German lines.

The Huns seemed to realize that something more than an ordinary attack
from the air was impending, for soon after the anti-aircraft guns began
firing a swarm of German aviators took the air, and there was no
shirking battle this time. The Huns so evidently felt the desperate need
of driving away their attackers, that this, more than what the major and
lieutenant had said, convinced Tom and Jack that they were at last on
the track of the big gun.

Of course the two boys could not communicate with one another, but they
said afterward that their thoughts were the same.

The battle of the air opened with a rush and a roar. The Germans, though
outnumbered by their opponents, did not hesitate, but came on fiercely.
They attacked first the big photographing planes, for they realized that
these were the real "eyes" of the squadron. The impressions they
received, and the views they carried back, might mean the failure of the
German plans.

But the French were ready for this, and the swift little Nieuports,
dashing here and there, swooping and rising, attacked the other planes
vigorously.

It was give and take, hammer and tongs, fire and be fired on, smash and
be smashed. It was not as one-sided a battle as it would seem it might
have been owing to the superiority of numbers in favor of the French--at
least at first. Several of the Allies' planes were sent down, either out
of con