pounds, instead of a third as much for normal. His heart had to pump
against three times the normal resistance of gravity. His chest felt as
if it had a leaden weight on it. His tongue tried to crowd the back of
his mouth and strangle him. The sensation was that of a nightmare of
impossible duration. It was possible to move and possible to see. One
could breathe, with difficulty, and with titanic effort one could speak.
But there was the same feeling of stifling resistance to every movement
that comes in nightmares.

But Joe managed to keep his eyes focused. The dials of the instruments
said that everything was right. The tinny voice behind his head, its
timbre changed by the weighting of its diaphragm, said: "_All readings
check within accuracy of instruments. Good work!_"

Joe moved his eyes to a quartz window. The sky was black. But there were
stars. Bright stars against a black background. At the same instant he
saw the bright white disks of sunshine that came in the cabin portholes.
Stars and sunshine together. And the sunshine was the sunshine of
space. Even with the polarizers cutting off some of the glare it was
unbearably bright and hot beyond conception. He smelled overheated
paint, where the sunlight smote on a metal bulkhead. Stars and super-hot
sunshine together....

It was necessary to pant for breath, and his heart pounded horribly and
his eyes tried to go out of focus, but Joe Kenmore strained in his
acceleration-chair and managed to laugh a little.

"We did it!" he panted. "In case you didn't notice, we're out of--the
atmosphere and--out in space! We're--headed to join the Space Platform!"

2

The pressure of three gravities continued. Joe's chest muscles ached
with the exertion of breathing over so long a period. Six gravities for
fourteen seconds had been a ghastly ordeal. Three gravities for minutes
built up to something nearly as bad. Joe's heart began to feel fatigue,
and a man's heart normally simply doesn't ever feel tired. It became
more and more difficult to see clearly.

But he had work to do. Important work. The take-off rockets were
solid-fuel jobs, like those which launched the Platform. They were
wire-wound steel tubes lined with a very special refractory, with
unstable beryllium and fluorine compounds in them. The solid fuel burned
at so many inches per second. The refractory crumbled away and was
hurled astern at a corresponding rate--save for one small point. The
refrac