comber, and here the
wheels struggled with sand precariously ready to fall, and Bordman had a
sudden perception of the sands of Xosa II as the oceans that they really
were. The dunes were waves which moved with infinite slowness, but the
irresistible force of storm-seas. Nothing could resist them. Nothing!

They traveled over similar dunes for two miles. Then they began to climb
the approaches to the mountains. And Bordman saw for the second
time--the first had been through the ports of the landing-boat--where
there was a notch in the mountain wall and sand had flowed out of it
like a waterfall, making a beautifully symmetrical cone-shaped heap
against the lower cliffs. There were many such falls. There was one
place where there was a sand-cascade. Sand had poured over a series of
rocky steps, piling up on each in turn to its very edge, and then
spilling again to the next.

They went up a crazily slanting spur of stone, whose sides were too
steep for sand to lodge on, and whose narrow crest had a bare thin
coating of powder.

The landscape looked like a nightmare. As the car went on, wabbling and
lurching and dipping on its way, the heights on either side made Bordman
tend to dizziness. The coloring was impossible. The aridness, the
desiccation, the lifelessness of everything about was somehow shocking.
Bordman found himself straining his eyes for the merest, scrubbiest of
bushes and for however stunted and isolated a wisp of grass.

The journey went on for an hour. Then there came a straining climb up a
now-windswept ridge of eroded rock, and the attainment of its highest
point. The ground car went onward for a hundred yards and stopped.

They had reached the top of the mountain range, and there was
doubtlessly another range beyond. But they could not see it. Here, at
the place to which they had climbed so effortfully, there were no more
rocks. There was no valley. There was no descending slope. There was
sand. This was one of the sand plateaus which were a unique feature of
Xosa II. And Bordman knew, now, that the disputed explanation was the
true one.

Winds, blowing over the mountains, carried sand as on other worlds they
carried moisture and pollen and seeds and rain. Where two mountain
ranges ran across the course of long-blowing winds, the winds eddied
above the valley between. They dropped sand into it. The equivalent of
trade winds, Bordman considered, in time would fill a valley to the
mountain tops, ju