Space Tug | Page 9

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,