space of the plane there were four big crates. They
contained the pilot gyros for the most important object then being built
on Earth, and it wouldn't work properly without them. It was Joe's job
to take that highly specialized, magnificently precise machinery to its
destination, help to install it, and see to its checking after it was
installed.

He felt uneasy. Of course the pilot and co-pilot--the only two other
people on the transport plane--knew their stuff. Every imaginable
precaution would be taken to make sure that a critically essential
device like the pilot gyro assembly would get safely where it belonged.
It would be--it was being--treated as if it were a crate of eggs instead
of massive metal, smoothed and polished and lapped to a precision
practically unheard of. But just the same Joe was worried. He'd seen the
pilot gyro assembly made. He'd helped on it. He knew how many times a
thousandth of an inch had been split in machining its bearings, and the
breath-weight balance of its moving parts. He'd have liked to be back in
the cargo compartment with it, but only the pilot's cabin was
pressurized, and the ship was at eighteen thousand feet, flying west by
south.

He tried to get his mind off that impulse by remembering that at
eighteen thousand feet a good half of the air on Earth was underneath
him, and by hoping that the other half would be as easy to rise above
when the gyros were finally in place and starting out for space. The
gyros, of course, were now on their way to be installed in the
artificial satellite to be blasted up and set in an orbit around the
Earth as the initial stage of that figurative stepladder by which men
would make their first attempt to reach the stars. Until that Space
Platform left the ground, the gyros were Joe's responsibility.

The plane's co-pilot leaned back in his chair and stretched luxuriously.
He loosened his safety belt and got up. He stepped carefully past the
column between the right- and left-hand pilot seats. That column
contained a fraction of the innumerable dials and controls the pilots of
a modern multi-engine plane have to watch and handle. The co-pilot went
to the coffeepot and flipped a switch. Joe fidgeted again on his
improvised seat. Again he wished that he could be riding in back with
the crates. But it would be silly to insist on perching somewhere in the
freight compartment.

There was a steady roaring in the cabin--the motors. One's ears got
accus