ng them larger, so that they might also
provide passageway for personnel without the necessity for suiting up;
but as yet this had not been done. Perhaps later they would become
the forerunners of space corridors in the growing complex that would
inevitably develop around such a center of man's activities as this
laboratory in its thirty-six hour orbit.

At the far end of the longest anchor tube, ten miles away and barely
visible from here, was located the unshielded, remote-controlled power
pile that supplied the necessary energy for the operation of the
wheel. Later, it was hoped, experimental research now in progress
would make this massive device unnecessary. Solar energy would make an
ideal replacement; but as yet the research was not complete, and solar
energy had not yet been successfully harnessed for the high power
requirements of the Lab.

Inside this anchor tube ran the thick coaxial cable that fed
three-phase electric power from the atomic pile to the ship.

At the far end of the second anchor tube, five miles off in space, was
Project Hot Rod, the latest in the long series of experiments by which
man was attempting to convert the sun's radiant energy to useful
power.

At the end of the third anchor tube, and comparatively near the ship,
was the dump--a conglomeration of equipment, used and unused booster
rocket cases, oddments of all sorts, some to be installed aboard the
wheel, others to be used as building components of other projects; and
some oddments of materials that no one could have given a logical
reason for keeping at all except that they "might be useful"--all held
loosely together by short guidelines to an anchor ring at the tube's
end.

* * * * *

Carefully, Mike checked the servo-motor that would maintain the
stationary position of the ring with clocklike precision against the
drag of bearing friction and the spin of the hub on which it was
mounted; then briefly looked over the network of tubes before entering
the air lock.

Inside, he stripped off the heavy, complicated armor of an articulated
spacesuit, with its springs designed to compensate for the Bourdon
tube effect of internal air pressure against the vacuum of space,
appearing in the comfortable shorts, T-shirt, and light, knit
moccasins with their thin, plastic soles, that were standard wear for
all personnel.

He was ready to roll the wheel.

Feeling as elated as a schoolboy, Mike dove down