use for a few dozen times? That's Numbers Three and
Five."

"What about the old style models?"

"Half of them are out of commission, and the other half are holding the
islands still."

"Islands?"

"Those chunks of semisolid ground we have Administration built on. The
chunk that keeps Control Tower in one place."

"Well, what are they going to do--walk away?"

"That's just about right. The first week we were in operation we kept
wondering why we had to travel farther every day to get to the dredges.
Then we realized that solid ground on Venus isn't solid ground at all.
It's just big chunks of denser stuff that floats on top of the mud like
dumplings in a stew. But that was nothing compared to the other
things--"

They had reached the vicinity of the salvage operation on Number Five
dredge. To Kielland it looked like a huge cylinder-type vacuum cleaner
with a number of flexible hoses sprouting from the top. The whole
machine was three-quarters submerged in clinging mud. Off to the right a
derrick floated hub-deep in slime; grapplers from it were clinging to
the dredge and the derrick was heaving and splashing like a trapped
hippopotamus. All about the submerged machine were Mud-pups, working
like strange little beavers as the man supervising the operation wiped
mud from his face and carried on a running line of shouts, curses,
whistles and squeaks.

Suddenly one of the Mud-pups saw the newcomers. He let out a squeal,
dropped his line in the mud and bounced up to the surface, dancing like
a dervish on his broad webbed feet as he stared in unabashed curiosity.
A dozen more followed his lead, squirming up and staring, shaking gobs
of mud from their fur.

"No, _no_!" the man supervising the operation screamed. "_Pull_, you
idiots. Come back here! Watch _out_--"

The derrick wobbled and let out a whine as steel cable sizzled out.
Confused, the Mud-pups tore themselves away from the newcomers and
turned back to their lines, but it was too late. Number Five dredge
trembled, with a wet sucking sound, and settled back into the mud,
blub--blub--blub.

The supervisor crawled down from his platform and sloshed across to
where Simpson and Kielland were standing. He looked like a man who had
suffered the torment of the damned for twenty minutes too long. "No
more!" he screamed in Simpson's face. "That's all. I'm through. I'll
pick up my pay any time you get it ready, and I'll finish off my
contract at home, but I'm thr