ed for secrecy was past. Dixon threw the car in gear and
savagely pulled down the gas lever. With throttle wide open they
hurtled around the perilous curves of the narrow road, but always in
the rocks beside and above them they heard the scuttling progress of
some huge, many-legged creature that constantly kept pace with them.

They had occasional glimpses of the thing. Its pale jointed body was
some twenty feet in length, and had apparently been developed from
that of a centipede, with scores of racing legs that carried it with
startling speed over the rocky terrain.

The flivver raced madly on toward the blaze of kaleidoscopic colors
that marked the Centaurians' camp. Crawford's home loomed up now
barely a hundred yards ahead.

As though sensing that its quarry was about to escape, the hybrid
flashed a burst of speed that sent it on by the car for a full fifty
yards, then down into the road directly in front, where it whirled to
confront them. Dixon knew that he could never stop the car in the
short gap separating them from that huge upreared figure, and to
attempt swerving from the road upon either side was certain disaster.

He took the only remaining chance. With throttle wide open he sent the
little car hurtling straight for the giant centipede. He threw his
body in front of Ruth, to shield her as much as possible, just as they
smashed squarely into the hybrid.

The impact was too much for even that monstrous figure. It was hurled
bodily from the road to crash upon the jagged rocks at the bottom of a
thirty-foot gully. There it sprawled in a broken mass, too hopelessly
shattered to ever rise again.

The flivver skidded momentarily, then crumpled to a full stop against
the rocks at the side of the road. Dixon and Ruth scrambled from the
wreckage and raced for Crawford's home, scarcely fifty yards ahead.

* * * * *

They entered the laboratory and Ruth went directly over to where the
radio-projectile rested in a wall-rack. Dixon took the gleaming
cylinder down to examine it. Tapering to a rounded point at the front
end, it was nearly a yard long and about five inches in diameter.

"The mechanism inside the projectile is turned off now, of course,"
Ruth said. "If it were turned on, the projectile would have been on
its way to the space ship long ago, for the radio waves are as strong
here as at the Centaurians' camp."

The girl pointed to a small metal stud in the nose of the