our remained. They were the four immediately
behind Schwandorf. By blind chance the German had set foot on the narrow
isthmus separating the twin trenches, saving himself and the henchmen at
his heels from being engulfed. Now, as the Red Bones fought back from
the trap yawning before them, he and the surviving Peruvians stood
staring in momentary stupefaction at the welter of death on their
flanks. The malevolent yells of the savages had been cut short by the
catastrophe, and for the moment no sound was heard but the grunts and
snarls of struggling men.

Then into the semisilence burst a mighty voice--the battlefield voice of
McKay.

"Now! Fire at will!"

The walls spat flame and lead. A scythe of death swept above the ground
where stood Schwandorf and his riflemen. The Peruvian half-breeds
collapsed and lay still. But Schwandorf, shocked into activity by the
impact of that first word, dodged death by an infinitesimal fraction of
a second. Hurling himself backward, he struck the earth just as the
bullets sped through the air over him. With a lightning rebound he was
up while fresh cartridges were jumping into the rifle barrels menacing
him. Headlong he dived into the mass of Red Bones just behind. And the
next bullets darting after him killed the savages, leaving him unharmed.

The command of McKay and the crack of the rifles sent the quivering
Mayorunas into the fight. In a flash every masking tunnel cover was
thrown bodily into the air. Before the thunderstruck Red Bones had
recovered from the shock of finding their gun-armed leaders annihilated
and their mass being swept by swift-shooting rifles hidden in the walls,
they beheld a horde of vindictive foes erupting from under those walls
like warrior ants rushing from subterranean galleries. A blood-chilling
yell of concentrated fury smote their ears; a hastily loosed storm of
war arrows and short throwing-spears ripped into their flesh; a
swift-running arc of light-skinned men swerved around them, shooting and
stabbing as they went. They, who had so exultantly surrounded the homes
of women and children, now were surrounded in turn.

From the doorway of Monitaya's _maloca_ the two Brazilians and Jose now
leaped forth and, firing as they ran, dashed to hold the entrance of the
other big house. A few arrows whirred around them during their transit,
but the shafts were shot hurriedly and missed. Meanwhile the three
bushmen were striking down enemies at every flash of