ttle craft
barrel-rolled from under.

This sort of thing could not last forever. With each maneuver he was
losing altitude. Serrated roof-tops were already a scant fifteen
hundred feet beneath him, gaunt gray fingers that reached up to pluck
him from the sky.

Only half Allan's mind was concentrated on the aerial acrobatics. The
other half plodded a weary treadmill. In the nullite chamber beneath
Sugar Loaf's summit, he thought, were three couples whose knowledge
and wisdom had preserved them for the repeopling of the Earth. Their
children, and their children's children--starting from such a source
what heights might not the new race attain?

On the other hand, the ship that pursued him carried cowards who had
failed in mankind's supreme test; men who had lost their manhood,
ravening demi-beasts, half mad with loneliness and desire. As long as
they remained alive they would be a menace to those others, an unclean
band that would forever sully the new world with the old world's
evils. Even should Allan himself escape them by some trick of fortune,
they must inevitably find the little band of men--and women. A cold
chill ran through Dane as he visioned the result.

He was not afraid to die. And the girl in the cabin behind him--better
that she never awake than that she be the sport of Ra-Jamba's kind. A
grim resolve formed itself, and he watched for a chance to put it into
execution.

It came. At the end of a shifting maneuver the black 'copter was above
and behind the white. Dane's fingers played swiftly over the control
board. His ship flipped over backward, rolling on its long axis as it
somersaulted. It was directly beneath the other. Then the helio-vanes
screamed, and the American plane surged straight up!

* * * * *

A resounding crash split the air. Metal ripped, a fuel tank exploded.
A black wing scaled earthward, zigzagging oddly. Dane's craft and the
Eastern ship clung in an embrace of death. They started to drop. But,
queerly, the black plane fell faster, left the white one behind as its
descent gained speed till it splashed against concrete below. The
American helicopter was dropping, too, but sluggishly. Something was
buoying it up. Allan, momentarily struggling out of the welter of
blackness and pain into which the concussion had thrown him, heard a
familiar whine. His helio-vanes were still twirling, limply,
stutteringly, bent and twisted, but gripping the air suffici