as the Belgian cursed and struck at him, Achmet Zek appeared in
view.

Instantly the Belgian ceased his efforts with the dying animal at
his feet, and seizing his rifle, dropped behind the horse and fired
at the oncoming Arab.

His bullet, going low, struck Achmet Zek's horse in the breast,
bringing him down a hundred yards from where Werper lay preparing
to fire a second shot.

The Arab, who had gone down with his mount, was standing astride
him, and seeing the Belgian's strategic position behind his fallen
horse, lost no time in taking up a similar one behind his own.

And there the two lay, alternately firing at and cursing each other,
while from behind the Arab, Tarzan of the Apes approached to the
edge of the forest. Here he heard the occasional shots of the
duelists, and choosing the safer and swifter avenue of the forest
branches to the uncertain transportation afforded by a half-broken
Abyssinian pony, took to the trees.

Keeping to one side of the trail, the ape-man came presently to a
point where he could look down in comparative safety upon the fighters.
First one and then the other would partially raise himself above
his breastwork of horseflesh, fire his weapon and immediately drop
flat behind his shelter, where he would reload and repeat the act
a moment later.

Werper had but little ammunition, having been hastily armed by