flyer was far different
than to hurry at the pace his companion now set across one of these
narrow bridges suspended high above the street. And he was sure that
the surface under them vibrated as if the slightest extra poundage
would separate it from its supports and send it, and them, crashing
down.

Luckily the distance they had to cover was relatively short, but Raf
swallowed a sigh of relief as they reached the door at the other end.
They were now in a tower which, unluckily, proved to be only a way
station before another swing out over empty space on a span which
sloped down! Raf clutched at the guide rail, the presence of which
suggested that not all the users of this road were as nonchalant as
the officer who tripped lightly ahead. This must explain the other's
bare feet--on such paths they were infinitely safer than his own
boots.

The downward sloping bridge brought them to a square building which
somehow had an inhabited look which those crowding around it lacked.
Raf gained its door to become aware of a hum, a vibration in the wall
he touched to steady himself, hinting at the drive of motors, the
throb of machinery inside the structure. But within, the officer
passed along a corridor to a ramp which brought them out, after what
was for Raf a steep climb, upon the roof. Here was not one of the
tongue-shaped craft such as had first met them in the city, but a
gleaming globe. The officer stopped, his eyes moving from the Terran
to the machine, as if inviting Raf to share in his own pride. To the
pilot's mind it bore little resemblance to any form of aircraft past
or present with which he had had experience in his own world. But he
did not doubt that it was the present acme of alien construction, and
he was eager to see it perform.

He followed the officer through a hatch at the bottom of the globe,
only to be confronted by a ladder he thought at first he could not
climb, for the steps were merely toe holds made to accommodate the
long, bare feet of the crew. By snapping on the magnetic power of his
space boots, Raf was able to get up, although at a far slower speed
than his guide. They passed several levels of cabins before coming
out in what was clearly the control cabin of the craft.

To Raf the bank of unfamiliar levers and buttons had no meaning, but
he paid strict attention to the gestures of his companion. This was
not a space ship he gathered. And he doubted whether the aliens had
ever lifted from