--

But he halted again on the verge of firing. For he had not stopped
listening, and now his trained ears picked out another, an unfamiliar
sound from the background of noises.

It was a queer rattle and scurry, mingled with a high-pitched buzz that
could only come from a number of small but high-speed motors. It was not
a sound the exact like of which Dworn remembered having heard before. He
went rigid, staring, as the sound's source came into view.

A column of little machines--lighter even than a beetle, and more
elongated--advancing in single file, multiple wheels swerving in the
leader's tracks as the column wound nearer along the mountainside. As
the firelight fell on them they gleamed with the mild sheen of aluminum.
Round vision-ports stared glassily, and turbines buzzed feverishly
shrill.

With astonishing bravado, the flimsy little vehicles, one behind
another, came parading onto the wreck-strewn slope.

And what was more startling still--no two of them were alike. The leader
mounted a winch in plain view; behind came another machine fitted with
oddly-shaped grappling claws, and next one bearing a mysterious device
terminating in front in a sort of flexible trunk.... Strangely, too,
they didn't seem to carry any armament--no snouting guns, no flame or
gas projectors.

Despite that fact or perhaps because of it, something sounded an alarm
deep in Dworn's mind.

Their diversity itself was uncanny, that was certain. In all Dworn's
experience, machines were the work of races whose traditions of
construction, handed down from forgotten antiquity, were as fixed and
unvarying as the biological heredity that made one race light-haired,
another dark....

A hatch-cover clanged shut, and another. The squabbling scavengers had
finally noticed the appearance of outside competition. The one upslope
raced its engine uncertainly, swung round to face the buzzing invaders,
hesitated.

The newcomers, for their part, seemed oblivious to the scavengers'
presence. Their column began dispersing. A grapple-armed machine laid
hold on one of the wrecked beetles and, whining with effort, sought to
drag it to leveler ground. A second, following, spat a burst of sparks
and extended a gleaming arm tipped by the singing blue radiance of a
cutting torch.

The first-come scavenger growled throatily and lumbered toward the
interlopers, plainly taking heart from their air of harmless stupidity.
Behind it, the other scavenger came