hteen hundred feet of steel grid overhead. It made a
crisscross, ring-shaped wall more than a quarter-mile high and almost to
the top of the surrounding mountains. But the valley was not exactly a
normal one. It was a crater, now: a steeply sloping, conical pit whose
walls descended smoothly to the outer girders of the red-painted,
glistening steel structure. More girders for the completion of the grid
projected from the sand just outside its half-mile circle. And in the
landing grid there was now a smaller, elaborate, truss-braced object. It
rested on the rocky ground, and it was not painted, and it was quite
small. A hundred feet high, perhaps, and no more than three hundred
across. But it was visibly a miniature of the great, now-uncovered,
re-painted landing grid which was qualified to handle interstellar cargo
ships and all the proper space-traffic of a minerals-colony planet.

A caterwheel truck came lurching and rolling and rumbling down the side
of the pit. It had a sunshade and ground-reflector wings, and Bordman
rode tiredly on a hobbyhorse saddle in its back cargo section. He wore a
heat-suit.

The truck reached the pit's bottom. There was a tool shed there. The
caterwheel-truck bumped up to it and stopped. Bordman got out, visibly
cramped by the jolting, rocking, exhausting-to-unaccustomed-muscles
ride.

"Do you want to go in the shed and cool off?" asked Chuka brightly.

"I'm all right," said Bordman curtly. "I'm quite comfortable, so long as
you feed me that expanded air." It was plain that he resented needing
even a special air supply. "What's all this about? Bringing the
_Warlock_ in? Why the insistence on my being here?"

"Ralph has a problem," said Chuka blandly. "He's up there. See? He needs
you. There's a hoist. You've got to check degree-of-completion anyhow.
You might take a look around while you're up there. But he's anxious for
you to see something. There where you see the little knot of people. The
platform."

Bordman grimaced. When one was well started on a survey, one got used to
heights and depths and all sorts of environments. But he hadn't been up
on steel-work in a good many months. Not since a survey on Kalka IV
nearly a year ago. He would be dizzy at first.

He accompanied Chuka to the spot where a steel cable dangled from an
almost invisibly thin beam high above. There was a strictly improvised
cage to ascend in--planks and a handrail forming an insecure platform
that might hold