But at this appalling juncture, when life hung on the passing moment, a
piercing shout rang out above the roar of the waters.

It came from a point behind them, and, despite the imminent peril all
three looked around.

A small canoe was darting across the Xingu toward them, so close to the
foot of the rapids, that it danced about like a cork and seemed certain
to be submerged every minute.

In this frail craft sat the giant Ziffak, propelling it across the
furious swirl with such prodigious power that though the spume dashed
over it, the boat was driven by the sheer power of his mighty arms
under, above, and through the waters.

It was he who uttered the resounding cry which caused the wondering
explorers to turn their heads, and stayed the uplifted arms of the
venomous Aryks.

All saw the giant head chieftain of the Murhapas who repeated the shout
and added an exclamation that was a command, forbidding his allies to
hurl a single weapon.

They must have deemed him mad, but if so he was ten times more to be
dreaded than if sane. Not a javelin was launched, but all stood
motionless awaiting his arrival, and doubtless believing he meant them
to pause only long enough to place himself at their head as the leader.

They must have thought, too, that his appearance so filled the whites
with fear that their arms were paralyzed, for, though he was in direct
range, not a hand of the foreigners was raised to do him hurt.

Coming with such tremendous speed, Ziffak occupied but a moment in
passing the remaining distance. Before the prow of his boat could
touch land, he flung the paddle aside, spurned the canoe with his foot,
caught up his huge spear, and with one bound placed himself opposite
the wondering trio of white men, while two more leaps landed him among
the Aryks.

Grimcke, Ashman and Long had read aright the meaning of the amazing
demonstration and calmly awaited the issue.

Pausing in the very middle of the dusky force, he addressed them in
their native tongue, with savage gestures and a fierceness of tones
which rendered every word audible amid the roaring tumult.

Only a second or two was required for him to finish his harangue, when
he made a final command for them to fall back, emphasized by the swing
of his tremendous arms.

No more striking proof could have been given of the sway of this mighty
warrior over his vassals, than was shown by their instant obedience to
the order, which fell upon them li