e had bumped into a second crawling figure.

CHAPTER XVI.

THE STRUGGLE IN THE CAVE.

In spite of the pain that shot through his head following the contact,
Hal did not lose his coolness or his presence of mind. Although his
head hurt badly, he did not utter a sound.

His unseen antagonist apparently was too surprised to make an outcry,
or it may have been that he thought he had bumped into a wall. If the
latter were his thought he was quickly undeceived.

As he sat back on his haunches, to rub his head, Hal moved lightly
forward, and, judging the distance by the sound of his enemy's
movements, fell on top of him.

He had gauged the distance to a nicety, and before the German could
cry out, one of the lad's hands sank deep into his throat. But the
latter was a powerful man and not to be overcome easily. He hurled the
lad from him with a quick shove, at the same time twisting on the
wrist of the hand that gripped his throat.

The pain was almost unbearable and Hal was forced to loosen his hold.
But again the lad sprang, before the German could take the offensive,
and this time struck out fiercely with his right fist. The German
uttered a cry of pain, and with one hand delivered a smashing blow at
the face so close to his own.

But Hal had figured on this move and had calculated the time of the
blow perfectly. With a quick movement of his head he avoided the huge
fist, and there came a terrific howl of pain from the German. The blow
had passed over the lad's head and the German's fist had crashed into
the solid wall.

And at the same instant there came the sound of a shot from Chester's
end of the cave.

This sound spurred Hal to greater activity, for he realized now that
their presence had been discovered by those on the outside. He felt
certain that the sound of the shot would probably bring new visitors
into the cave from the end he was supposed to guard.

Quickly, then, while his opponent was still in agony from the
self-inflicted blow, Hal drew his revolver and, reversing it, struck
out in the direction of a muttered curse.

He was rewarded by another groan of anguish and a moment later by the
sound of a falling body. Quickly the lad leaped forward, his weapon
held ready to strike again. But there was no need of a second blow.
The German was unconscious.

By great exertion Hal succeeded in turning his wounded adversary over
and pushed him slowly along the passageway, using him as a shield in