o be much more dangerous
to the man behind it than to the Gern it was aimed at. Automatic
crossbows were far better.

Woods goats had been trapped and housed during the summers in shelters
where sprays of water maintained a temperature cool enough for them to
survive. Only the young were kept when fall came, to be sheltered
through the winter in one of the caves. Each new generation was
subjected to more heat in the summer and more cold in the winter than
the generation before it and by the year one hundred and sixty the woods
goats were well on their way toward adaptation.

The next year they trapped two unicorns, to begin the job of adapting
and taming future generations of them. If they succeeded they would have
utilized the resources of Ragnarok to the limit--except for what should
be their most valuable ally with which to fight the Gerns: the
prowlers.

For twenty years prowlers had observed a truce wherein they would not go
hunting for men if men would stay away from their routes of travel. But
it was a truce only and there was no indication that it could ever
evolve into friendship.

Three times in the past, half-grown prowlers had been captured and caged
in the hope of taming them. Each time they had paced their cages,
looking longingly into the distance, refusing to eat and defiant until
they died.

To prowlers, as to some men, freedom was more precious than life. And
each time a prowler had been captured the free ones had retaliated with
a resurgence of savage attacks.

There seemed no way that men and prowlers could ever meet on common
ground. They were alien to one another, separated by the gulf of an
origin on worlds two hundred and fifty light-years apart. Their only
common heritage was the will of each to battle.

But in the spring of one hundred and sixty-one, for a little while one
day, the gulf was bridged.

* * * * *

Schroeder was returning from a trip he had taken alone to the east,
coming down the long canyon that led from the high face of the plateau
to the country near the caves. He hurried, glancing back at the black
clouds that had gathered so quickly on the mountain behind him. Thunder
rumbled from within them, an almost continuous roll of it as the clouds
poured down their deluge of water.

A cloudburst was coming and the sheer-walled canyon down which he
hurried had suddenly become a death trap, its sunlit quiet soon to be
transformed into roaring