[Transcriber's Note: This etext was produced from
Astounding Science Fiction August 1957.
Extensive research did not uncover any evidence that
the U.S. copyright on this publication was renewed.]
I
"The probability of unfavorable consequences cannot be zero in any
action of common life, but the probability increases by a very high
power as a series of actions is lengthened. The effect of moral
considerations, in conduct, may be stated to be a mathematically
verifiable reduction in the number of unfavorable possible chance
happenings. Of course, whether this process is termed the
intelligent use of probability, or ethics, or piety, makes no
difference in the fact. It is the method by which unfavorable chance
happenings are made least probable. Arbitrary actions such as we
call criminal cannot ever be justified by mathematics. For
example ..."
_Probability and Human Conduct_
Fitzgerald
Calhoun lay in his bunk and read Fitzgerald on "Probability and Human
Conduct" as the little Med Ship floated in overdrive. In overdrive
travel there is nothing to do but pass the time away. Murgatroyd, the
_tormal_, slept curled up in a ball in one corner of the small ship's
cabin. His tail was meticulously curled about his nose. The ship's
lights burned steadily. There were those small random noises which
have to be provided to keep a man sane in the dead stillness of a ship
traveling at thirty times the speed of light. Calhoun turned a page and
yawned.
Something stirred somewhere. There was a click, and a taped voice said:
"_When the tone sounds, break-out will be five seconds off._"
A metronomic ticking, grave and deliberate, resounded in the stillness.
Calhoun heaved himself up from the bunk and marked his place in the
book. He moved to and seated himself in the control chair and fastened
the safety belt. He said:
"Murgatroyd! Hark, hark the lark in Heaven's something-or-other doth
sing. Wake up and comb your whiskers. We're getting there."
Murgatroyd opened one eye and saw Calhoun in the pilot's chair. He
uncurled himself and padded to a place where there was something to
grab hold of. He regarded Calhoun with bright eyes.
"_BONG!_" said the tape. It counted down.
"Five--four--three--two--one--"
It stopped. The ship popped out of overdrive. The sensation was
unmistakable. Calhoun's stomach seemed to turn over twice, and he had
a sickish feeling of spiraling dizzily in what was somehow a cone. He
swallowed. Murgatroyd made gulping noises. Outside, everything changed.
The sun Maris blazed silently in emptiness off to port. The Cetis
star-cluster was astern, and the light by which it could be seen had
traveled for many years to reach here, though Calhoun had left Med
Headquarters only three weeks before. The third planet of Maris swung
splendidly in its orbit. Calhoun checked, and nodded in satisfaction.
He spoke over his shoulder to Murgatroyd.
"We're here, all right."
"_Chee!_" shrilled Murgatroyd.
He uncoiled his tail from about a cabinet-handle and hopped up to look
at the vision-screen. What he saw, of course, meant nothing to him. But
all _tormals_ imitate the actions of human beings, as parrots imitate
their speech. He blinked wisely at the screen and turned his eyes to
Calhoun.
"It's Maris III," Calhoun told him, "and pretty close. It's a colony
of Dettra Two. One city was reported started two Earth-years ago. It
should just about be colonized now."
"_Chee-chee!_" shrilled Murgatroyd.
"So get out of the way," commanded Calhoun. "We'll make our approach
and I'll tell 'em we're here."
He made a standard approach on interplanetary drive. Naturally, it was
a long process. But after some hours he flipped over the call-switch
and made the usual identification and landing request.
"Med Ship _Aesclipus Twenty_ to ground," he said into the transmitter.
"Requesting co-ordinates for landing. Our mass is fifty tons. Repeat,
five-oh tons. Purpose of landing, planetary health inspection."
He relaxed. This job ought to be purest routine. There was a landing
grid in the spaceport city on Maris III. From its control room
instructions should be sent, indicating a position some five planetary
diameters or farther out from the surface of that world. Calhoun's
little ship should repair to that spot. The giant landing grid should
then reach out its specialized force-field and lock onto the ship, and
then bring it gently but irresistibly down to ground. Then Calhoun,
representing Med Service, should confer gravely with planetary
authorities about public health conditions on Maris III.
It was not to be expected that anything important would turn up.
Calhoun would deliver full details of recent advances in the progress
of medicine. These might already have reached Maris III in the ordinary
course of commerce, but he would make sure. He might--but it was
unlikely--learn of some novelty worked out here. In any case, within
three days he should return to the small Med Ship, the landing grid
should heave it firmly heavenward to not less than five planetary
diameters distance, and there release it. And Calhoun and Murgatroyd
and the Med Ship should flick into overdrive and speed back toward
Headquarters, from whence they had come.
* * * * *
Right now, Calhoun waited for an answer to his landing call. But he
regarded the vast disk of the nearby planet.
"By the map," he observed to Murgatroyd, "the city ought to be on the
shore of that bay somewhere near the terminus. Close to the sunset
line."
His call was answered. A voice said incredulously on the space-phone
speaker:
"_What? What's that? What's that you say?_"
"Med Ship _Aesclipus Twenty_," Calhoun repeated patiently. "Requesting
co-ordinates for landing. Our mass is fifty tons. Repeat, five-oh tons.
Purpose of landing, planetary health inspection."
The voice said more incredulously still:
"_A Med Ship? Holy_--" By the change of sound, the man down on the
planet had turned away from the microphone. "_Hey! Listen to this_--"
There was abrupt silence. Calhoun raised his eyebrows. He drummed on
the control desk before him.
There was a long pause. A very long pause. Then a new voice came on
the space phone, up from the ground:
"_You up aloft there! Identify yourself!_"
Calhoun said very politely:
"This is Med Ship _Aesclipus Twenty_. I would like to come to ground.
Purpose of landing, health inspection."
"_Wait_," said the voice from the planet. It sounded strained.
A murmuring sounded, transmitted from fifty thousand miles away. Then
there was a click. The transmitter down below had cut off. Calhoun
raised his eyebrows again. This was not according to routine. Not
at all! The Med Service was badly overworked and understaffed. The
resources of interplanetary services were always apt to be stretched to
their utmost, because there could be no galactic government as such.
Some thousands of occupied planets, the closest of them light-years
apart--or weeks of traveling--couldn't hold elections or have political
parties for the simple reason that travel even in overdrive was too
slow. They could only have service organizations whose authority
depended on the consent of the people served, and whose support had to
be gathered when and as it was possible.
But the Med Service was admittedly important. The local Sector
Headquarters was in the Cetis cluster. It was a sort of interstellar
clinic, with additions. It gathered and disseminated the results
of experience in health and medicine among some thousands of
colony-worlds, and from time to time it made contact with other
Headquarters carrying on the same work elsewhere. It admittedly
took fifty years for a new technique in gene-selection to cross the
so-far-occupied part of the galaxy, but it was a three-year voyage
in overdrive to cover the same distance direct. And the Med Service
was worth while. There was no problem of human ecological adjustment
it had so far been unable to solve, and there were some dozens of
planets whose human colonies owed their existence to it. There was
nowhere--nowhere at all--that a Med Ship was not welcomed on its errand
from Headquarters.
"Aground there!" said Calhoun sharply. "What's the matter? Are you
landing me or not?"
There was no answer. Then, suddenly, every sound-producing device in
the ship abruptly emitted a hoarse and monstrous noise. The lights
flashed up and circuit-breakers cut them off. The nearby-object horn
squawked. The hull-temperature warning squealed. The ship's internal
gravity-field tugged horribly for an instant and went off. Every device
within the ship designed to notify emergency clanged or shrieked or
roared or screamed. There was a momentary bedlam.
It lasted for part of a second only. Then everything stopped. There was
no weight within the ship, and there were no lights, and there was dead
silence, and Murgatroyd made whimpering sounds in the darkness.
Calhoun thought absurdly to himself, "_According to the book, this is
an unfavorable chance consequence of something or other._" But it was
more than an unfavorable chance occurrence. It was an intentional and
drastic and possibly a deadly one.
"Somebody's acting up," said Calhoun measuredly, in the blackness.
"What's the matter with them?"
He flipped the screen switch to bring back vision of what was outside.
The vision screens of a ship are very carefully fused against over-load
burnouts, because there is nothing in all the cosmos quite as helpless
and foredoomed as a ship which is blind in the emptiness of space. But
the screens did not light again. They couldn't. The cutouts hadn't
worked in time.
Calhoun's scalp crawled. But as his eyes adjusted, he saw the palely
fluorescent handles of switches and doors. They hadn't been made
fluorescent in expectation of an emergency like this, of course, but
they would help a great deal. He knew what had happened. It couldn't be
but one thing--a landing-grid field clamped on the fifty-ton Med Ship
with the power needed to grasp and land a twenty-thousand-ton liner.
At that strength it would paralyze every instrument and blow every
cut-off. It could not be accident. The reception of the news of his
identity, the repeated request that he identify himself, and then the
demand that he wait--This murderous performance was deliberate.
"Maybe," said Calhoun in the inky-black cabin, "as a Med Ship our
arrival is an unfavorable chance consequence of something--or the
unfavorableness is--and somebody means to keep us from happening. It
looks like it."
Murgatroyd whimpered.
"And I think," added Calhoun coldly, "that somebody may need a swift
kick in the negative feedback!"
He released himself from the safety belt and dived across the cabin
in which there was now no weight at all. In the blackness he opened a
cabinet door. What he did inside was customarily done by a man wearing
thick insulating gloves, in the landing grid back at Headquarters.
He threw certain switches which would allow the discharge of the
power-storage cells which worked the Med Ship's overdrive. Monstrous
quantities of energy were required to put even a fifty-ton ship
into overdrive, and monstrous amounts were returned when it came
out. The power amounted to ounces of pure, raw energy, and as a
safety-precaution such amounts were normally put into the Duhanne cells
only just before a Med Ship's launching, and drained out again on its
return. But now, Calhoun threw switches which made a rather incredible
amount of power available for dumping into the landing-grid field about
him--if necessary.
He floated back to the control chair.
* * * * *
The ship lurched--violently. It was being moved by the grid field
without any gentleness at all. Calhoun's hands barely grasped the back
of his pilot's chair before the jerk came, and it almost tore them
free. He just missed being flung against the back wall of the cabin by
the applied acceleration. But he was a long way out from the planet. He
was at the end of a lever fifty thousand miles long. For that lever to
be used to shake him too brutally would require special adjustments.
But somebody was making them. The jerk reversed directions. He was
flung savagely against the chair to which he'd been clinging. He
struggled. Another yank, in another direction. Another one still. It
flung him violently into the chair.
Behind him, Murgatroyd squealed angrily as he went hurtling across the
cabin. He grabbed for holding-places with all four paws and his tail.
Another shake. Calhoun had barely clipped the safety belt fast before
a furious jolt nearly flung him out of it again to crash against the
cabin ceiling. Yet another vicious surge of acceleration. He scrabbled
for the controls. The yanks and plungings of the ship increased
intolerably. He was nauseated. Once he was thrust so furiously into the
control chair that he was on the verge of blacking out, and then the
direction of thrust was changed to the exact opposite so that the blood
rushing to his head seemed about to explode it. His arms flailed out of
control. He became dazed. But when his hands were flung against the
control board, despite their bruising he tried to cling to the control
knobs, and each time he threw them over. Practically all his circuits
were blown, but there was one--
His numbing fingers threw it. There was a roar, so fierce that it
seemed an explosion. He'd reached the switch which made effective the
discharge-circuit of his Duhanne cells. He'd thrown it. It was designed
to let the little ship's overdrive power-reserve flow into storage
at Headquarters on return from duty. Now, though, it poured into the
landing-grid field outside. It amounted to hundreds of millions of
kilowatt hours, delivered in the fraction of a second. There was the
smell of ozone. The sound was like a thunder clap.
But abruptly there was a strange and incredible peace. The lights came
on waveringly as his shaking fingers restored the circuit-breakers.
Murgatroyd shrilled indignantly, clinging desperately to an instrument
rack. But the vision screens did not light again. Calhoun swore.
Swiftly, he threw more circuit-restorers. The nearest-object indicator
told of the presence of Maris III at forty-odd thousand miles.
The hull-temperature indicator was up some fifty-six degrees. The
internal-gravity field came on, faintly, and then built up to normal.
But the screens would not light. They were permanently dead. Calhoun
raged for seconds. Then he got hold of himself.
"_Chee-chee-chee!_" chattered Murgatroyd desperately. "_Chee-chee!_"
"Shut up!" growled Calhoun. "Some bright lad aground thought up a new
way to commit murder. Damned near got away with it, too! He figured
he'd shake us to death like a dog does a rat, only he was using a
landing-grid field to do it with! Right now, I hope I fried him!"
But it was not likely. Such quantities of power as are used to handle
twenty-thousand-ton space liners are not controlled direct, but
by relays. The power Calhoun had flung into the grid field should
have blown out the grid's transformers with a spectacular display
of fireworks, but it was hardly probable it had gotten back to the
individual at the controls.
"But I suspect," observed Calhoun vengefully, "that he'll consider this
business an unfavorable occurrence! Somebody'll twist his tail, too,
either for trying what he did or for not getting away with it! Only, as
a matter of pure precaution--"
His expression changed suddenly. He'd been trying not to think of the
consequences of having no sight of the cosmos outside the ship. Now he
remembered the electron telescope. It had not been in circuit, so it
could not have been burned out like his vision screens. He switched it
on. A star field appeared over his head.
"_Chee-chee!_" cried Murgatroyd hysterically.
Calhoun glanced at him. The jerking of the ship had shifted the
instruments in the rack to which Murgatroyd clung. Clipped into place
though they were, they'd caught Murgatroyd's tail and pinched it
tightly.
"You'll have to wait," snapped Calhoun. "Right now I've got to make us
look like a successful accident. Otherwise whoever tried to spread us
all over the cabin walls will try something else!"
The Med Ship flung through space in whatever direction and at
whatever velocity it had possessed when the grid field blew. Calhoun
shifted the electron-telescope field and simultaneously threw on the
emergency-rocket controls. There was a growling of the pencil-thin,
high-velocity blasts. There was a surging of the ship.
"No straight-line stuff," Calhoun reminded himself.
He swung the ship into a dizzy spiral, as if innumerable things had
been torn or battered loose in the ship and its rockets had come on of
themselves. Painstakingly, he jettisoned in one explosive burst all
the stored waste of his journey which could not be disposed of while
in overdrive. To any space-scanning instrument on the ground, it would
look like something detonating violently inside the ship.
"Now--"
The planet Maris III swung across the electron telescope's field. It
looked hideously near--but that was the telescope's magnification. Yet
Calhoun sweated. He looked at the nearest-object dial for reassurance.
The planet was nearer by a thousand miles.
"Hah!" said Calhoun.
He changed the ship's spiral course. He changed it again. He abruptly
reversed the direction of its turn. Adequate training in space-combat
might have helped plot an evasion-course, but it might have been
recognizable. Nobody could anticipate his maneuvers now, though. He
adjusted the telescope next time the planet swept across its field, and
flipped on the photorecorder. Then he pulled out of the spiral, whirled
the ship until the city was covered by the telescope, and ran the
recorder as long as he dared keep a straight course. Then he swooped
toward the planet in a crazy, twisting fall with erratic intermissions,
and made a final lunatic dash almost parallel to the planet's surface.
At five hundred miles, he unshielded the ports which of necessity had
to be kept covered in clear space. There was a sky which was vividly
bright with stars. There was a vast blackness off to starboard which
was the night side of the planet.
He went down. At four hundred miles the outside pressure indicator
wavered away from its pin. He used it like a pitot-tube recording,
doing sums in his head to figure the static pressure that should exist
at this height, to compare with the dynamic pressure produced by his
velocity through the near hard vacuum. The pressure should have been
substantially zero. He swung the ship end-for-end and killed velocity
to bring the pressure-indication down. The ship descended. Two hundred
miles. He saw the thin bright line of sunshine at the limb of the
planet. Down to one hundred. He cut the rockets and let the ship fall
silently, swinging it nose up.
* * * * *
At ten miles he listened for man-made radiation. There was nothing in
the electromagnetic spectrum but the crackling of static in an electric
storm which might be a thousand miles away. At five miles height the
nearest-object indicator, near the bottom of its scale, wavered in a
fashion to prove that he was still moving laterally across mountainous
country. He swung the ship and killed that velocity, too.
At two miles he used the rockets for deceleration. The pencil-thin
flame reached down for an incredible distance. By naked-eye observation
out a port he tilted the fiercely-roaring, swiftly-falling ship until
hillsides and forests underneath him ceased to move. By that time he
was very low indeed.
He reached ground on a mountainside which was lighted by the blue-white
flame of the rocket-blast. He chose an area in which the tree tops were
almost flat, indicating something like a plateau underneath. Murgatroyd
was practically frantic by this time because of his capture and the
pinching of his tail, but Calhoun could not spare time to release
him. He let the ship down gently, gently, trying to descend in an
absolutely vertical line.
If he didn't do it perfectly, he came very close. The ship settled
into what was practically a burned-away tunnel among monstrous trees.
The high-velocity slender flame did not splash when it reached ground.
It penetrated. It burned a hole for itself through humus and clay
and bedrock. When the ship touched and settled, there was boiling
molten stone some sixty feet underground, but there was a small
scratching sound as it came to rest. A flame-amputated tree-limb rubbed
tentatively against the hull.
Calhoun turned off the rockets. The ship swayed slightly and there were
crunching noises. Then it was still on its landing fins.
"Now," said Calhoun, "I can take care of you, Murgatroyd."
He flicked on the switches of the exterior microphones--much more
sensitive than human ears. The radiation-detectors were still in
action. They reported only the cracklings of the distant storm.
But the microphones brought in the moaning of wind over nearby
mountaintops, and the almost deafening susurrus of rustling leaves.
Underneath these noises there was a bedlam of other natural sounds.
There were chirpings and hootings and squeaks, and the gruntings made
by native animal life. These sounds had a singularly peaceful quality.
When Calhoun toned them down to be no more than background-noises, they
suggested the sort of concert of night-creatures which to men has
always seemed an indication of purest tranquility.
Presently Calhoun looked at the pictures the photorecorder had taken
while the telescope's field swept over the city. It was the colony-city
reported to have been begun two years before, to receive colonists from
Dettra Two. It was the city of the landing grid which had tried to
destroy the Med Ship as a dog kills a rat--by shaking it to fragments,
some fifty thousand miles in space. It was the city which had made
Calhoun land with his vision-plates blinded, that had made him pretend
his ship was internally a wreck: which had drained his power-reserves
of some hundreds of millions of kilowatt hours of energy. It was the
city which had made his return to Med Headquarters impossible.
He inspected the telescopic pictures. They were very clear. They showed
the city with astonishing detail. There was a lacy pattern of highways,
with their medallions of multiple-dwelling units. There were the lavish
park areas between the buildings of this planetary capital. There was
the landing grid itself--a half-mile-high structure of steel girders, a
full mile in diameter.
But there were no vehicles on the highways. There were no specks on the
crossing bridges to indicate people on foot. There were no copters on
the building roofs, nor were there objects in mid-air to tell of air
traffic.
The city was either deserted or it had never been occupied. But it was
absolutely intact. The structures were perfect. There was no indication
of past panic or disaster, and even the highways had not been overgrown
by vegetation. But it was empty--or else it was dead.
But somebody in it had tried very ferociously and with singular
effectiveness to try to destroy the Med Ship.
Because it was a Med Ship.
Calhoun raised his eyebrows and looked at Murgatroyd.
"Why is all this?" he asked. "Have you any ideas?"
"_Chee!_" shrilled Murgatroyd.