ot only a ghost,
you are an insane ghost_. _Only a madman would have undertaken such a
journey._

The cabin heeled wildly as the machine grappled a ledge and, its engine
panting at full throttle, levered itself upward a few more feet.

He had commanded the spider girl to find the route by which her people
had descended. But twice already they had missed the way and had arrived
at dead ends beyond which it was impossible to climb higher; twice they
had been forced to descend and search for an easier path. It had been
scarcely noon when they started; now the sun was already sinking low.

Dworn could not even be sure that he would find his sworn enemies beyond
the Barrier. But the duty of vengeance was all he had left to live for,
since what was to have been his triumphal return had ended in
bereavement and catastrophe.

_And a dead man_, thought Dworn bleakly, _needs something to live for,
even more than other people do_.

The world came level again, for the moment. The machine sidled
precariously along a narrow ledge girdling an unscalable wall of rock,
as Qanya sought a spot to resume the ascent. Dworn winced at the thought
that the way might be blocked again. But, no--fifty yards further on,
the wall was breached, and toppled boulders formed a perilous but not
impossible stairway.

Just as Qanya grasped the levers which would set the spider scrambling
upward once more, there was a sound--one grown hatefully familiar to
Dworn since the night before, the feverish buzzing of a number of light
high-speed engines. He opened his mouth to hiss a warning, but Qanya
too had heard. Instantly she guided the spider-machine as close as
possible to the cliff, where the hollowed rock afforded some shelter,
and twirled a knob that made it sink down, legs folding compactly.

They waited scarcely breathing. A couple of times before they had
huddled like this, while flights of the winged enemies whistled over ...
but the wingless ones? It seemed impossible that they should be up here,
where surely nothing that ran on wheels could travel....

* * * * *

The head of a column of the aluminum crawlers came into view, whirring
along the ledge with a confident air of knowing where they were going.
One by one, the little machines rolled past within a few feet of the
crouching spider, hastening on with an uncanny pre-occupation.

Dworn saw that, like those he had seen earlier, they were of diverse
kinds