er of the blue beasts.

He could not retreat to the trees. But the newcomer was moving with
the same ponderous self-confidence its fellow had shown earlier. Vye
dodged right, headed for the rocks by the gap. As he pulled himself
into that temporary fortification, the wounded beast dragged out of
the woods below. He thought it was blind, yet some instinct drove it
after him.

Shaking from fatigue, Vye steadied his forearm on the top of the rock,
brought up the ray tube. Less than two yards away now was the
deceptively open mouth of the gap. If he threw himself at that, would
the elasticity of the unseen curtain hurl him back into the claws of
the enemy?

He fired his blast at the head of the unwounded beast. It screeched,
threw out its arms, and one of those paws struck against its wounded
fellow. With a cry, that one flung itself at its companion in the
hunt, and they tangled in a body-to-body battle terrible in its utter
ferocity. Vye edged along the cliff determined to reach the cave and
Hume. And the two blue things seemed intent on finishing each other
off.

The one from the wood was done, the fangs of the other ripping out its
throat. Tearing viciously the victor made sure of its kill, then its
seared head came up, swung about to face Vye. He guessed it was aware
of his movements whether it could see or not.

But he was not prepared for the speed of its attacking lunge.
Heretofore the creatures had given the impression of brute strength
rather than agility. And he had been almost fatally deceived. He
jumped backwards, knowing he must elude that attack, for he could not
survive hand-to-hand combat with the alien thing.

There was a moment of dazed disorientation, a weird sensation of
falling through unstable space in which there had never been and never
would be firm footing again. He was rolling across rock--outside the
curtain of the gap.

He sat up, the feeling of being adrift in unmeasurable nothingness
making him sick, to watch mistily as the blue beast came to a halt.
Whimpering it turned, but before it reached the level of the woods, it
sagged to its knees, fell face forward and was still, a destructive
machine no longer controlled by life.

Vye tried to understand what had happened. He had somehow broken
through that barrier which made the valley a prison. For a moment all
that mattered was his freedom. Then he looked apprehensively behind
him along the road to the open, more than half expecting t