full throttle. The wheels spun for
one sickening instant, then the little machine lunged forward from
beneath the fresh landslide and was climbing, bucking and slewing, up
the slope of loose soil created by the ones before.

The caterpillar loomed black and enormous on his left hand, so close
that it could not have brought its guns to bear even if its crew had
expected the beetle to take this daring way out. With its shovel lowered
and half-buried, it could not swing round quickly--Dworn had counted on
that.

As the beetle's flank cleared the corner of the digging blade with
inches to spare, Dworn's gun turret passed in line with the space
between the blade and the caterpillar's treads, and he jabbed the firing
button. The explosion wreathed the monster's forward half in smoke and
dust, and into that cloud it tilted forward, teetered ponderously and
then slid headlong to the bottom of the wash as the loosened bank gave
way conclusively under its great weight.

Dworn looked back from the hill crest to see it still floundering,
treads furiously churning sand, struggling to fight clear of the
avalanche it had carried with it. The beetle laughed full-throatedly,
without rancor. This hadn't been the first nor the tightest corner he'd
been in during the dangerous course of his wanderyear; and in that hard
school of life you learned not to worry about danger already past.

At another time, he might have returned to the battle in hope of
capturing the additional supplies the caterpillar carried and--still
more valuable booty--the chart it would have, showing the location of
its other caches. But now he was in a hurry--this refueling foray had
cost him a couple of hours, and the moon was already high.

So he slipped quietly away over the ridge and set his course to the
east.

Beyond the hilly land, the terrain ironed out into level alkali flats
where a vanished lake had been in the long-gone days when the earth was
fertile. There he opened the throttle wide. The plain, white in the
moonlight, rolled under the racing wheels at ninety and a hundred miles
an hour; air whistled over the carapace....

Impatience surged up in Dworn once more. Eagerly he pictured his
forthcoming reunion with his native horde--and with Yold, his father,
chief of the horde.

Countless times in the long wanderyear--in moments when death loomed
nearer than it had in the brush just past, and he despaired of surviving
his testing, or in other mome