like a reel, darting downward to
avoid being raked by machine-gun fire, and then coming up on the tail of
a Hun with the advantage all on his side.

Jack, still denied his share of action, continued to watch Tom out of
the corner of his eye. He felt like giving a shout when presently he saw
one of the Hun machines plunge downward as though a shot had paralyzed
the arm of the pilot. Over and over it went, bursting into smoke and
flames while speeding toward the earth.

There could be no doubt but that Tom would add another count to his
score, though he was already reckoned an ace, being accredited with
seven clear-cut victories.

But the other Hun aviator had taken advantage of the thrilling moment to
dart in and deliver a hot fire. Jack could see the spurt of the
machine-gun as it blazed away furiously, the two planes passing one
another. He felt his heart in his throat for fear that Tom might be
caught napping, for the distance was too great to make sure of what was
happening.

Suddenly a cold hand seemingly clutched Jack's heart. Tom was falling
rapidly! It was no nose-dive, but bore all the marks of either an engine
gone dead or of some mishap to the pilot. So did gallant Tom's plane
vanish from the sight of his horrified chum, being swallowed up in the
dense volumes of smoke rolling upward from the battleground below.
Jack's heart felt like lead in his breast.

CHAPTER II

YANKEE PLUCK

WHEN Tom Raymond sent one of his Hun opponents whirling down toward the
far distant earth he naturally experienced the glow that comes to a
victor in a stubbornly contested battle.

The gratification was all the more profound because of the fact that he
had taken on two adversaries at the same time. Any air pilot who was
capable of holding his own against an enemy numerically superior had
reason to feel satisfied.

He quickly saw, however, that this did not mean the end of the fight.
That other crafty Hun had swung unexpectedly and was now pouring in a
furious fire. Tom realized that his assistant had ceased firing. Had the
machine-gun become jammed? He was hanging partly from his seat. Was he
badly injured in the bargain? Still, despite all this handicap, Tom
would possibly have come through in good shape had not something
happened to his engine just then. After all, even a Liberty motor could
play a trick on its pilot master, just as that fine French engine on his
former Spad machine had done a few times.

The