"Right!" he replied. "Set yourselves."
Mike flung a switch, and a voice began to chatter behind Joe's head. It
was the voice from the communications-room atop the Shed, now far below
and far behind. Mike settled himself in the tiny acceleration-chair
built for him. The Chief squirmed to comfort in his seat. Haney took his
hands from the equalizing adjustments he had to make so that Joe's use
of the controls would be exact, regardless of moment-to-moment
differences in the thrust of the various jets.
"We've got a yaw right," said the Chief sharply. "Hold it, Joe!"
Joe waited for small quivering needles to return to their proper
registrations.
"Back and steady," said the Chief a moment later. "Okay!"
The tinny voice behind Joe now spoke precisely. Mike had listened to it
while the work of take-off could be divided, so that Joe would not be
distracted. Now Joe had to control everything at once.
The roar of the pushpots outside the ship had long since lost the volume
and timbre of normal atmosphere. Not much sound could be transmitted by
the near-vacuum outside. But the jet motors did roar, and the sound
which was not sound at such a height was transmitted by the metal cage
as so much pure vibration. The walls and hull of the spaceship picked up
a crawling, quivering pulsation and turned it into sound. Standing waves
set up and dissolved and moved erratically in the air of the cabin.
Joe's eardrums were strangely affected. Now one ear seemed muted by a
temporary difference of air pressure where a standing wave lingered for
a second or two. Then the other eardrum itched. There were creeping
sensations as of things touching one and quickly moving away.
Joe swung a microphone into place before his mouth.
"All set," he said evenly. "Brief me."
The tinny voice said:
"_You are at 65,000 feet. Your curve of rate-of-climb is flattening out.
You are now rising at near-maximum speed, and not much more forward
velocity can be anticipated. You have an air-speed relative to surface
of six-nine-two miles per hour. The rotational speed of Earth at this
latitude is seven-seven-eight. You have, then, a total orbital speed of
one-four-seven-oh miles per hour, or nearly twelve per cent of your
needed final velocity. Since you will take off laterally and practically
without air resistance, a margin of safety remains. You are authorized
to blast._"
Joe said:
"Ten seconds. Nine ... eight ... seven ... six ... five ... four ...
three ... two ... one...."
He stabbed the master jato switch. And a monstrous jato rocket, built
into each and every one of the pushpots outside, flared chemical fumes
in a simultaneous, gigantic thrust. A small wire-wound jato for
jet-assisted-take-off will weigh a hundred and forty pounds and deliver
a thousand pounds of thrust for fourteen seconds. And that is for
rockets using nonpoisonous compounds. The jatos of the pushpots used the
beryllium-fluorine fuel that had lifted the Platform and that filled the
take-off rockets of Joe's ship. These jatos gave the pushpots themselves
an acceleration of ten gravities, but it had to be shared with the cage
and the ship. Still....
Joe felt himself slammed back into his seat with irresistible,
overwhelming force. The vibration from the jets had been bad. Now he
didn't notice it. He didn't notice much of anything but the horrible
sensations of six-gravity acceleration.
It was not exactly pain. It was a feeling as if a completely intolerable
and unbearable pressure pushed at him. Not only on the outside, like a
blow, but inside too, like nothing else imaginable. Not only his chest
pressed upon his lungs, but his lungs strained toward his backbone. Not
only the flesh of his thighs tugged to flatten itself against his
acceleration-chair, but the blood in his legs tried to flow into and
burst the blood-vessels in the back of his legs.
The six-gravity acceleration seemed to endure for centuries. Actually,
it lasted for fourteen seconds. In that time it increased the speed of
the little ship by rather more than half a mile per second, something
over 1,800 miles per hour. Before, the ship had possessed an orbital
speed of a shade over 1,470 miles an hour. After the jato thrust, it was
traveling nearly 3,400 miles per hour. It needed to travel something
over 12,000 miles per hour to reach the artificial satellite of Earth.
The intolerable thrust ended abruptly. Joe gasped. But he could allow
himself only a shake of the head to clear his brain. He jammed down the
take-off rocket firing button. There was a monstrous noise and a mighty
surging, and Haney panted, "Clear of cage...."
And then they were pressed fiercely against their acceleration chairs
again. The ship was no longer in its launching cage. It was no longer
upheld by pushpots. It was free, with its take-off rockets flaming. It
plunged on up and out. But the acceleration was less. Nobody can stand
six gravities for long. Anybody can take three--for a while.
Joe's body resisted movement with a weight of four hundred and fifty
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
refractory was not all exactly alike. Some parts of it crumbled away
faster, leaving a pattern of baffles which acted like a maxim silencer
on a rifle, or like an automobile muffler. The baffles set up eddies in
the gas stream and produced exactly the effect of a rocket motor's
throat. But the baffles themselves crumbled and were flung astern, so
that the solid-fuel rockets had always the efficiency of gas-throated
rocket motors; and yet every bit of refractory was reaction-mass to be
hurled astern, and even the steel tubes melted and were hurled away with
a gain in acceleration to the ship. Every fraction of every ounce of
rocket mass was used for drive. No tanks or pumps or burners rode
deadhead after they ceased to be useful.
But solid-fuel rockets simply can't be made to burn with absolute
evenness as a team. Minute differences in burning-rates do tend to
cancel out. But now and again they reinforce each other and if
uncorrected will throw a ship off course. Gyros can't handle such
effects. So Joe had to watch his instruments and listen to the tinny
voice behind him and steer the ship against accidental wobblings as the
Earth fell away behind him.
He battled against the fatigue of continuing to live, and struggled with
gyros and steering jets to keep the ship on its hair-line course. He
panted heavily. The beating of his heart became such a heavy pounding
that it seemed that his whole body shook with it. He had to do
infinitely fine precision steering with hands that weighed pounds and
arms that weighed scores of pounds and a body that had an effective
weight of almost a quarter of a ton.
And this went on and went on and on for what seemed several centuries.
Then the voice in the speaker said thickly: "_Everything is in the
clear. In ten seconds you can release your rockets. Shall I count?_"