ts
pale chill light washed needle-sharp crags and fantastically painted
cliffs, shale and sand and the wreck of geological ages. The low harsh
brush crunched under the man's feet, writhing and crackling its
impotent protest. Otherwise it was still, a deep and taut and somehow
waiting stillness.

The hound shattered the quiet with an eager yelp and plunged forward.
Hot scent! Riordan dashed after him, trampling through dense bush,
panting and swearing and grinning with excitement.

Suddenly the brush opened underfoot. With a howl of dismay, the hound
slid down the sloping wall of the pit it had covered. Riordan flung
himself forward with tigerish swiftness, flat down on his belly with
one hand barely catching the animal's tail. The shock almost pulled
him into the hole too. He wrapped one arm around a bush that clawed at
his helmet and pulled the hound back.

Shaking, he peered into the trap. It had been well made--about twenty
feet deep, with walls as straight and narrow as the sand would allow,
and skillfully covered with brush. Planted in the bottom were three
wicked-looking flint spears. Had he been a shade less quick in his
reactions, he would have lost the hound and perhaps himself.

He skinned his teeth in a wolf-grin and looked around. The owlie must
have worked all night on it. Then he couldn't be far away--and he'd be
very tired--

As if to answer his thoughts, a boulder crashed down from the nearer
cliff wall. It was a monster, but a falling object on Mars has less
than half the acceleration it does on Earth. Riordan scrambled aside
as it boomed onto the place where he had been lying.

"Come on!" he yelled, and plunged toward the cliff.

For an instant a gray form loomed over the edge, hurled a spear at
him. Riordan snapped a shot at it, and it vanished. The spear glanced
off the tough fabric of his suit and he scrambled up a narrow ledge to
the top of the precipice.

The Martian was nowhere in sight, but a faint red trail led into the
rugged hill country. _Winged him, by God!_ The hound was slower in
negotiating the shale-covered trail; his own feet were bleeding when
he came up. Riordan cursed him and they set out again.

They followed the trail for a mile or two and then it ended. Riordan
looked around the wilderness of trees and needles which blocked view
in any direction. Obviously the owlie had backtracked and climbed up
one of those rocks, from which he could take a flying leap to some
other