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Title: The Brain-Stealers of Mars
Date of first publication: 1936
Author: John W. Campbell, Jr. (1910-1971)
Date first posted: Dec. 19, 2022
Date last updated: Dec. 19, 2022
Faded Page eBook #20221240

This eBook was produced by: Al Haines

This file was produced from images generously made available by Internet Archive/American Libraries.




  The Brain-Stealers of Mars


  by

  John W. Campbell, Jr.



  _Copyright, 1936, by Beacon Magazines, Inc.,
  and originally published in
  December, 1936, Thrilling Wonder Stories_




  _Penton and Blake find Mars an unexpectedly
  pleasant place to be--until they run afoul
  of the_ thushol, _which can imitate anything!_




Rod Blake looked up with a deep chuckle.  The sky of Mars was almost
black despite the small brilliant Sun and the brighter stars and
planets that shone visibly.  Earth, most brilliant of all, was
scarcely sixty million miles away.

"They'll have a fine time chasing us back there, Ted."  He nodded
toward the brilliant planet.

Ted Penton smiled beatifically.

"They're probably investigating all our known haunts.  It's their own
fault if they can't find us--outlawing research on atomic power."

"They had some provocation, you must admit.  Koelenberg should have
been more careful.  When a man takes off some three hundred square
miles of territory spang in the center of Europe in an atomic
explosion, you can't blame the rest of the world for being a bit
skittish about atomic power research."

"But they might have had the wit to see that anybody that did get the
secret would not wait around for the Atomic Power Research Death
Penalty--but would light out for parts and planets quite unknown and
leave the mess in the hands of a lawyer till the fireworks quieted
down.  It was obvious that when we developed atomic power we'd be the
first men to reach Mars.  Nobody could follow to bring us back unless
they accepted the hated atomic power and used it," argued Blake.

"Wonder how old Jamison Montgomery Palborough made out with our
claims," mused Penton.  "He said he'd have it right in three months.
This is the third month and the third planet.  We'll let the
government stew and sail on, fair friend, sail on.  I still say that
was a ruined city we saw as we landed."

"I think it was myself but I remember the way you did that kangaroo
leap on your neck the first time you stepped out on the Moon.  You
certainly saw stars."

"We're professionals at walking under cockeyed gravities now.
Moon--Venus--"

"Yes, but I'm still not risking my neck on the attitude of a strange
planet _and_ a strange race at the same time.  We'll investigate the
planet a bit first and yonder mudhole is the first stop.  Come on."

They reached the top of one of the long rolling sand dunes and the
country was spread out below them.  It looked exactly as it had been
from the last dune that they had struggled up.  It was unendingly
red--like an iron planet, badly neglected and rusted.



The mudhole was directly beneath them, an expanse of red and brown
slime, dotted here and there with clumps of dark red foliage.

"The stuff looks like Japanese maple," said Blake.

"Evidently doesn't use chlorophyll to get the sun's energy.  Let's
collect a few samples.  You have your violet-gun and I have mine.  I
guess it's safe to split.  There's a large group of things down on
the left that look a little different.  I'll take them while you go
straight ahead.

"Gather any flowers, fruits, berries or seeds you see.  Few
leaves--oh, you know--what we got on Venus.  General junk.  If you
find a small plant put on your gloves and yank it out.  If you see a
big one steer clear.  Venus had some peculiarly unpleasant specimens."

Blake groaned.  "You're telling me!  I'm the bright boy that fell for
that pretty fruit and climbed right up between the stems of a scissor
tree.  Uhuh--I shoot 'em down.  Go ahead and good luck."

Penton swung off to the left while Blake slogged ahead to a group of
weird-looking plants.  They were dome-shaped things, three feet high,
with a dozen long drooping sword-shaped leaves.

Cautiously Blake tossed a bit of stone into the center of one.  It
gave off a mournful drumming boom but the leaves didn't budge.  He
tried a rope on one leaf but the leaf neither stabbed, grabbed nor
jerked away--as he had half expected after his lesson with the
ferocious plants of Venus.  Blake pulled a leaf off, then a few more.
The plant acted quite plantlike, which surprised him pleasantly.

The whole region seemed seeded with a number of the things, nearly
all about the same size.  A few, sprinkled here and there, were in
various stages of development, from a few protruding sword-leaves, to
little three-inch domes on up to the fullgrown plants.  Carefully
avoiding the larger ones Rod plucked two small ones and thrust them
into his specimen bag.  Then he stood off and looked at one of the
domes that squatted so dejectedly in the thick gummy mud.

"I suppose you have some reason for being like that but a good solid
tree would put you all in the shade and collect all the sunlight
going--which is little enough."  He looked at them for some seconds
picturing a stout Japanese maple in this outlandish red brown gum.

He shrugged and wandered on, seeking some other type of plant.  There
were few.  Apparently this particular species throttled out other
varieties very thoroughly.  He wasn't very anxious anyway--he was
much more interested in the ruined city they had seen from the ship.
Ted Penton was cautious.

Eventually Blake followed his winding footsteps back toward the ship.
About where his trail showed he had gathered his first samples he
stopped.  There was a Japanese maple there.  It stood some fifteen
feet tall and the bark was beautifully regular in appearance.  The
leaves were nearly a quarter of an inch thick and arranged with a
peculiar regularity as were the branches.  But it was very definitely
a Japanese maple.

Rod Blake's jaw put a severe strain on the hinges thereof.  It
dropped some three inches and Blake stared.  He stared with steady
blank gaze at that perfectly impossible Japanese maple.  He gawked
dumbly.  Then his jaw snapped shut abruptly and he cursed.

The leaves were stirring gently and they were not a quarter of an
inch thick.  They were paper thin and delicately veined.  Furthermore
the tree was visibly taller and three new branches had started to
sprout, irregularly now.  They sprouted as he watched, growing not as
twigs but as fully formed branches extending themselves gradually.
As he stared harder at them they dwindled rapidly to longer twigs and
grew normally.

Rod let out a loud yip and made tracks rapidly toward the point where
he'd last seen Ted Penton.  Penton's tracks curved off and Rod
steamed down as fast as Mars' light gravity permitted, to pull up
short as he rounded a corner of another sword-leaf dome clump.
"Ted," he panted, "come over here.  There's a--a--weird thing.  A--it
looks like a Japanese maple but it doesn't.  Because when you look at
it it changes."

Rod stopped and started back, beckoning Ted.  Ted didn't move.

"I don't know what to say," he said quite clearly, panting and
sounding excited, though it was a quite unexciting remark except for
one thing.  He said it in Rod Blake's voice!

Rod stiffened.  Then he backed away hurriedly, stumbled over his feet
and sat down heavily in the sand.  "For the love of--Ted--Ted!
Wh-what did you s-s-say?"

"I don't know wh-what to s-s-say."

Rod groaned.  It started out exactly like his own voice, changed
rapidly while it spoke and wound up as a fair imitation of Ted's.
"Oh, Lord," he groaned, "I'm going back to the ship--in a hurry."

He started away, then looked back over his shoulder.  Ted Penton was
moving now, swaying on his feet peculiarly.  Delicately he picked up
his left foot, shook it gently like a man trying to separate himself
from a piece of flypaper.  Rod moved even more rapidly than he had
before.

Long but rapidly shrinking roots dangled from the foot.  Gooey mud
dropped from them as they shrank into the foot.  Rod turned again
with the violet-gun in his hand.  It thrummed to blasting atomic
energy.  A pencil beam of ravening ultra-violet fury shot out and a
hazy ball of light surrounded it.

The figure of Ted Penton smoked suddenly and a hole the size of a
golf ball drove abruptly through the center of the head, to the
accompaniment of a harsh whine of steam and spurts of oily smoke.
The figure did not fall.  It slumped.  It melted rapidly like a
snowman in a furnace.  The fingers ran together, the remainder of the
face dropped, contracted and became horrible.

It was suddenly the face of a man whose pouched and dulled eyes had
witnessed and enjoyed every evil the worlds knew, with weirdly
glowing eyes that danced and flamed for a moment in screaming fury of
deadly hate--and dissolved with the last dissolution of the writhing
face.



And the arms grew long, very long and much wider.  Rod stood frozen
while the very wide and rapidly widening arms beat up and down.  The
thing took off and flapped awkwardly away and for an instant the last
trace of the hate-filled eyes glittered again in the sun.

Rod Blake sat down and laughed.  He laughed and laughed again at the
very funny sight of the melting face on the bat-bodied thing that had
flown away with a charred hole in the middle of its grapefruit-sized
head.  He laughed even louder when another Ted-Penton-thing came
around the corner of the vegetable clump on the run.  He aimed at the
center of its head.

"_Fly away!_" he yelled as he pressed the little button down.

This one was cleverer.  It ducked.  "Rod--for the love of--_Rod_,
shut up!"  It spoke.

Rod stopped and considered slowly.  This one talked with Ted Penton's
voice.  As it got up again he aimed more carefully and flashed again.
He wanted it to fly away too.  It ducked again, in another direction
this time, and ran in rapidly.  Rod got up hastily and fled.  He fell
suddenly as some fibrous thing lashed out from behind and wrapped
itself unbreakably about his arms and body, binding him helplessly.

Penton looked down at him, panting.  "What's the trouble, Rod?  And
why in blazes were you shooting your gun at me?"

Rod heard himself laugh again uncontrollably.  The sight of Ted's
worried face reminded him of the flying thing with the melted
face--like an overheated wax figure.  Penton reached out a deliberate
hand and cracked him over the face, hard.  In a moment Rod steadied
and Penton removed the noose from his arms and body.  Blake sighed
with relief.

"Thank God, it's you, Ted!" he said.  "Listen, I saw you--_you_--not
thirty seconds ago.  You stood over there and I spoke to you.  You
answered in _my_ voice.  I started away and your feet came up out of
the ground with roots on them, like a plant's.  I shot you through
the forehead and you melted down like a wax doll to a bat-thing that
sprouted wings and flew away."

"Uhh--" said Penton soothingly.  "Funny, at that.  Why were you
looking for me?"

"Because there's a Japanese maple where I was that grew while my back
was turned and changed its leaves while I looked at it."

"Oh, Lord!" said Penton unhappily, looking at Rod.  Then, more
soothingly, "I think we'd better look at it."

Rod led the way back on his tracks, when the maple should have been
in sight it wasn't at all.  When they reached the spot where Rod's
tracks showed it should have been it wasn't there.  There was only a
somewhat wilted sword-bush.  Rod stared blankly at it, then went over
and felt it cautiously.  It remained placidly squatted, a slightly
bedraggled lump of vegetation.

"That's where it was," said Blake dully.  "But it isn't there any
more.  I know it was there."

"It must have been an--er--mirage," decided Penton.  "Let's get back
to the ship.  We've had enough walking practise."

Rod followed him, shaking his head.  He was so wrapped up in his
thoughts that he nearly fell over Penton when Ted stopped with a soft
unhappy gurgling noise.  Ted turned around and looked at Rod
carefully.  Then he looked ahead again.

"Which," he asked at length, "is you?"

Rod looked ahead of Penton over his shoulder.  Another Rod was also
standing in front of Penton.  "My God," said Rod, "it's _me_ this
time!"

"I am, of course," said the one in front.  It said it in Rod Blake's
voice.

Ted looked at it, and finally shut his eyes.  "I don't believe it.
Not at all.  _Wo bist du gewesen, mein Freund?_"

"Was sagst du?" said the one in front.  "But why the _Deutsch_?"

Ted Penton sat down slowly and thoughtfully.  Rod Blake stared at Rod
Blake blankly, slightly indignant.

"Let me think," said Penton unhappily.  "There must be some way to
tell.  Rod goes away from me and then I come around the corner and
find him laughing insanely.  He takes a shot at me.  It looks and
talks like Rod--but he says crazy things.

"Then I go for a walk with him--or it--and meet another one that at
least seems less insane than the first one.  Well, well--I know
German of course and so does Rod.  Evidently this thing can read
minds.  Must be like a chameleon only more so."

"What do you mean?" asked Rod Blake.  It doesn't particularly matter
which one.

"A chameleon can assume any color it wants to at will.  Lots of
animals have learned to imitate other animals for safety but it takes
them generations to do it.  This thing apparently can assume any
shape or color at will.  A minute ago it decided the best form for
the locality was a sword-bush.  Some of these things must be real
plants then.

"Rod thought of a maple tree, thought of the advantages of a maple
tree, so it decided to try that, having read his mind.  That was why
it was wilted-looking--this isn't the right kind of country for maple
trees.  It lost water too fast.  So it went back to the sword-bush.

"Now this one has decided to try being Rod Blake, clothes and all.
But I haven't the foggiest notion which one is Rod Blake.  It won't
do a bit of good to try him on languages we know because he can read
our minds.  I know there must be some way.  There must--there
must--oh, yes.  It's simple.  Rod, just burn me a hole in that thing
with your violet-gun."

Rod reached for his gun at once with a sigh of relief and triggered
quickly.  The phoney Rod melted hastily.  About half of it got down
into the boiling mud before Rod incinerated the rest with the intense
ultra-violet flare of the pistol.

Rod sighed.  "Thank the Lord it was me.  I wasn't sure for awhile,
myself."

Ted shook himself, put his head in his hands, and rocked slowly.  "By
the Nine Gods of the Nine Planets, what a world!  Rod, for the love
of heaven, stay with me hereafter--permanently.  And whatever you do
don't lose that pistol.  They can't grow a real violet-gun but if
they pick one up heaven help us.  Let's get back to the ship and away
from this damned place.  I thought you were mad.  My error.  It's
just the whole bloody planet that's mad."

"I was--for awhile.  Let's move."

They moved.  They moved hastily back across the sand dunes to the
ship.



"They're centaurs," gasped Blake.  "Will you look at that one over
there--a nice little calico.  There's a beautiful little strawberry
roan.  What people!  Wonder why the city is so dilapidated if the
people are still here in some numbers.  Set 'er down, will you, Ted?
They haven't anything dangerous or they'd have a better city."

"Uhmmmm--I suppose that's right.  But I'd hate to have one of those
fellows nudge me.  They must weigh something noticeable, even
here--about twelve hundred pounds back on Earth.  I'm setting down in
that square.  You keep your hand on that ten-inch ion-gun while I
step out."

The ship settled with a soft _thumpf_ in the deep sandy dust of the
ruined city square.  Half a hundred of the centaurs were trotting
leisurely up with a grizzled old Martian in the lead, his mane sparse
and coarse.  Ted Penton stepped out of the lock.

"_Pholshth_," the Martian said after a moment's inspection.  He
extended his hands out horizontally from his shoulders, palms upward
and empty.

"Friends," said Ted, extending his arms in a similar gesture, "I am
Penton."

"Fasthun Loshthu," explained the centaur, indicating himself.
"Penshun."

"He sounds like an ex-soldier," came Blake's voice softly.  "Pension.
Is he okay?"

"I think so.  You can leave that post anyway.  Shut off the main
atomics, start auxiliary B and close the rooms.  Lock the controls
with the combination and come on out.  Bring your ion-gun as well as
your ultra-violet.  Lock the doors."

"Blazes!  I want to come out this afternoon.  Oh, well..."  Blake
went to work hurriedly and efficiently.  It was some thirty seconds
before he was through in the power room.  He stepped eagerly into the
lock.

He stopped dead.  Penton was on his back, moving feebly, the old
centaur bent over him with his long, powerful fingers fixed around
the man's throat.  Penton's head was shaking slowly back and forth on
the end of his neck in a loose rather-detached way.

Blake roared and charged out of the lock, his two powerful pistols
hastily restored to his holsters.  He charged out--and sailed neatly
over the centaur's back, underestimating Mars' feeble grip.  In an
instant he was on his feet again and returning toward his friend when
a skillful left forefoot caught his legs, and sent him tumbling.  The
heavy bulk of an agile young centaur landed on his back.

Blake turned--his was a smaller lighter body, far more powerfully
muscled.  In a moment the Earthman broke the centaur's grip and
started through the six or seven others that surrounded him.  A
grunted word of command dissolved the melee and Blake stood up,
leaping toward Penton.

Penton sat on the ground, rocking slowly back and forth, his head
between his hands.  "Oh, Lord, they all do it here."

"Ted--are you all right?"

"Do I sound it?" Penton asked unhappily.  "That old bird just opened
up my skull and poured a new set of brains in.  Hypnotic teaching--a
complete university education in thirty seconds--all done with
hypnotism and no mirrors used.  They have the finest education
system.  Heaven preserve us from it."

"_Shthuntho ishthu thiu lomal?_" asked the old Martian pleasantly.

"_Ishthu psoth lonthul timul_," groaned Penton.  "The worst of it is
it works.  I know his language as well as I know English."  Suddenly
he managed a slight grin.  He pointed to Blake and said, "Blake _omo
phusthu ptsoth_."

The old centaur's lined sparsely-bearded face smiled like a pleased
child's.  Blake looked at him uneasily.

"I don't like that fellow's expre--"  He stopped, hypnotized.  He
walked toward the old Martian with blank eyes and the grace of an
animated tailor's dummy.  He lay down and the old Martian's long
supple fingers circled his neck.  Gently they massaged the back of
his spine up to the base of his skull.

Penton smiled sourly from where he sat.  "Oh, you don't like his
face, eh?  Wait and see how you like his system."



The centaur straightened.  Slowly Blake sat up.  His head continued
to nod and weave in a detached way until he reached up gingerly, felt
around for it and took it firmly in his hands.  He rested his elbows
on his knees.

"We didn't both have to know his blasted language," he managed
bitterly at last.  "Languages always did give me headaches anyway."

Penton watched him unsympathetically.  "I hate repeating things and
you'll find it useful anyway."

"You are from the third planet," the Martian stated politely.

Penton looked at him in surprise, then rose to his feet gingerly.

"Get up slowly, Blake, I advise you for your own good."  Then to the
Martian, "Why, yes.  But you knew!  How?"

"My great-great grandfather told me of his trip to the third planet
before he died.  He was one of those that returned."

"Returned?  You Martians have been to Earth?" gasped Blake.

"I guessed that," said Penton softly.  "They're evidently the
centaurs of legend.  And I think they didn't go alone from this
planet."

"Our people tried to establish a colony there many many years ago.
It didn't succeed.  They died of lung diseases faster than they could
cross space.  The main reason they went in the first place was to get
away from the _thushol_.

"But the _thushol_ simply imitated local Earth-animals and thrived.
So the people came back.  We built many ships, hoping that since we
couldn't go the _thushol_ would.  But they didn't like Earth."  He
shook his head sorrowfully.

"The _thushol_.  So _that's_ what you call 'em."  Blake sighed.
"They must be a pest."

"They were then.  They aren't much any more."

"Oh, they don't bother you anymore?" asked Penton.

"No," said the old centaur apathetically.  "We're so used to them."

"How do you tell them from the thing they're imitating?" Penton asked
grimly.  "That's what I need to know."

"It used to bother us because we couldn't," Loshthu sighed.  "But it
doesn't anymore."

"I know--but how do you tell them apart?  Do you do it by mind
reading?"

"Oh, no.  We don't try to tell them apart.  That way they don't
bother us any more."



Penton looked at Loshthu thoughtfully for some time.  Blake rose
gingerly and joined Penton in his rapt contemplation of the grizzled
Martian.  "Uhmmmm," said Penton at last, "I suppose that is one way
of looking at it.  I should think it would make business rather
difficult though.  Also social relations, not knowing whether it was
your wife or just a real good imitation."

"I know.  We found it so for many years," Loshthu agreed.  "That was
why our people wanted to move to Earth.  But later they found that
three of the ship commanders were _thushol_ so the people came back
to Mars where they could live at least as easily as the _thushol_."

Penton mentally digested this for some moments while the half hundred
centaurs about stood patiently.

"We have myths on Earth of centaurs--people like you--and of magic
creatures who seemed one thing but when captured became snakes or
tigers or other unpleasant beasts.  If held long enough they reverted
to human shape and would then grant a wish.  Yes, the _thushol_ are
intelligent--they could have granted a simple Earth barbarian's wish."

Loshthu shook his head slowly.  "They are not intelligent, I believe.
Maybe they are.  But they have perfect memories for detail.  They
would imitate one of our number, attend our schools and so learn all
we knew.  They never invented anything for themselves."

"What brought about the tremendous decline in your civilization?  The
_thushol_?"

The centaur nodded.  "We forgot how to make space-ships and great
cities.  We hoped that would discourage the _thushol_ so they would
leave us.  But they forgot too so it didn't help."

"Good Lord," Blake sighed, "how in the name of the Nine Planets do
you live with a bunch like that?"

Loshthu looked at Blake slowly.  "Ten," he said.  "Ten planets.  You
can't see the tenth with any practicable instrument till you get out
beyond Jupiter.  Our people discovered it from Pluto."



Blake stared at him owlishly.  "But how can you live with this gang?
With a civilization like that--I should think you'd have found some
means of destroying them."

"We did.  We destroyed all the _thushol_.  Some of the _thushol_
helped us but we thought that they were our own people.  It happened
because a very wise but very foolish philosopher calculated how many
_thushol_ could live parasitically on our people.  Naturally the
_thushol_ took his calculations to heart.  Thirty-one percent of us
are _thushol_."

Blake looked around with a swiftly unhappy eye.  "You mean--some of
these here are _thushol_?" he asked.

Loshthu nodded.  "Always.  They reproduced very slowly at first, in
the form of an animal that was normally something like us and
reproduced as did other animals.  But then they learned to imitate
the amoebae when they studied in our laboratories.

"Now they simply split.  One big one will split into several small
ones and each small one will eat one of the young of our people and
take its place.  So we never know which is which.  It used to worry
us."  Loshthu shook his head slowly.

Blake's hair rose slightly away from his head, and his jaw dropped
away.  "My God!" he gasped.  "Why didn't you do something?"

"If we kill one we suspect we might be wrong, which would kill our
own child.  If we don't and just believe it our own child anyway it
at least gives us the comfort of believing it.  And if the imitation
is so perfect one can't tell the difference--what _is_ the
difference?"

Blake sat down again quietly.  "Penton," he said at length, "those
three months are up.  Let's get back to Earth--fast."

Penton looked at him.  "I wanted to a long time ago.  But I just
thought of something else.  Sooner or later some other man is going
to come here with atomic power and if he brings one of those
_thushol_ back to Earth with him accidentally, thinking it's his best
friend--well, I'd rather kill my own child than live with one of
those but I'd rather not do either.

"They can reproduce as fast as they can eat and if they eat like an
amoeba--heaven help us.  If you maroon one on a desert island it will
turn into a fish and swim home.  If you put it in jail it will turn
into a snake and go down the drainpipe.  If you dump it in the desert
it will turn into a cactus and get along real nicely, thank you."

"Good God!"

"And they won't believe us, of course.  I'm sure as blazes not going
to take one back to prove it.  I'll just have to get some kind of
proof from this Loshthu."

"I hadn't thought of that.  What can we get?"

"All I can think of is to see what they can let us have, then take
all we can and make a return trip with reputable and widely believed
zoologists and biologists to look into this thing.  Evolution had
produced some weird freaks but this is a freakier freak than has ever
been conceived."

"I still don't really believe it," Blake said.  "The only thing I am
firmly convinced of is my headache."

"It's real enough and logical enough.  Logical as hell--and hell on
Earth if they ever get there.  Evolution is always trying to produce
an animal that can survive anywhere, conquer all enemies, the fittest
of the surviving fit.  All life is based on one thing--protoplasm.

"Basically it's the same in every creature, every living thing, plant
or animal, amoeba or man.  It is just modified slightly, hooked
together in slightly different ways.  The _thushol_ are built of
protoplasm--but infinitely more adaptable protoplasm.  They can do
something about it, make it take the form of a bone cell and be part
of a thigh bone or be a nerve cell in a brain.

"From some of that ten-second-college-course Loshthu poured into us I
gather that at first the _thushol_ were good imitations outside--but
if you cut into one, you could see that the organs weren't there.
Now they have everything.  They went through Martian medical
colleges, of course, and know all about what makes a centaur tick.
So they make themselves with the same kind of tickers.  Oh, very
nice."

"They don't know much about us.  Maybe with the X-ray fluoroscope
screen we could have recognized their imitations of us," suggested
Blake.

"By no means.  If we knew the right form they'd read it in our minds
and have it.  Adaptive protoplasm.  Just think, you couldn't kill one
in an African jungle because, when a lion came along, it would be a
little lady lion.  And when an elephant showed up it would be a
helpless baby elephant.

"If a snake bit it I suppose the damned thing would turn into
something immune to snake bites--a tree or something like that.  I
just wonder where it keeps the very excellent brain it evidently has."

"Well, let's find out what Loshthu can offer us by way of proof."



It developed that the Martians had once had museums.  They still had
them because nobody was sufficiently interested to disturb their
age-long quiet.  Martians lived for centuries and their memories were
long.  Only once or twice in a life-time did a Martian enter a museum.

Penton and Blake spent hours in them, intensive hours under Loshthu's
guidance.  Loshthu had nothing but time and Penton and Blake didn't
want to linger.  They worked rapidly, collecting thin metal sheaves
of documents, ancient mechanisms, a thousand other valuable things.
They baled them with rope that they had brought from the ship when
they moved it nearer the museum.  Finally after hours of labor,
bleary-eyed from want of sleep, they started back again to the ship.

They stepped out of the gloomy dusk of the museum into the sunlit
entranceway.  Immediately, from behind a dozen pillars, a leaping
flashing group of men descended upon them, tore the books, the
instruments, the data sheaves from their hands.  They were upset,
slugged, trampled on and spun around.  There were shouts, cries and
curses.

Then there was silence.  Twelve Pentons and thirteen Blakes sat, lay
or stood about on the stone stairway.  Their clothes were torn, their
faces and bodies bruised.  There was even one black eye and another
developing swiftly.  But twelve Pentons otherwise looked exactly
alike, each carrying a bit of data material.  Thirteen Blakes were
identical, each carrying a bit of factual mustiness under his arm or
in his hand.

Loshthu looked at them and his lined old face broke into a pleased
smile.  "Ah," he said.  "There are more of you.  Perhaps some can
stay with us to talk now."

Penton looked up at Losthu, all the Pentons did.  Penton was quite
sure he was the Penton but he couldn't think of any way to prove it.
It was fairly evident that the _thushol_ had decided to try Earth
again.  He began to wonder just--

"Loshthu, just why," asked one of the Pentons in Penton's voice, "did
the _thushol_ not stay on Earth if they could live there?"

Penton was quite sure he was the one to think of that partic--

"Pardon me, but wasn't that the question I was going to ask?" said
another Penton in fury.

"I can apparently be spared the trouble of doing my own talking.  You
all help so," said one of the numerous Pentons angrily.

"Say, how are we going to tell who's who?" demanded one of the Blakes
abruptly.

"That damned mind-thief stole my question before I had a chance--"

"Why you--you--_you_ should talk!"

"I think," said one of the Pentons wearily, "you might as well stop
getting peeved, Blake, because they'll all act peeved when you do.
Pipe down and I'll pipe down and we'll see what our good friend,
Loshthu, has to say."

"Eh," sighed Loshthu.  "You mean about the _thushol_ leaving Earth?
They did not like it.  Earth is a poor planet and the people were
barbarians.  Evidently they are not so now.  But the thushol do not
like work and they found richer sustenance on Mars."

"I thought so," said a Penton.  "They've decided that Earth is richer
than Mars now and want a new host.  Don't draw that pistol, Blake!
Unfortunately, we had twenty-five ion-guns and twenty-five
violet-guns made up.  If we'd had more we would have more companions.

"We were exceedingly unfortunate in equipping ourselves so well in
the matter of clothing and being so thoughtful as to plan all of it
right, so that we carried a lot of each of the few kinds.  However, I
think we can improve things a little bit.

"I happen to remember that one ion-gun is out of commission and I had
the coils out of two of the violet-guns to repair them.  That makes
three guns out of service.  We will each stand up and fire, one at a
time, at the sand in front there.  The line forms on the right."

The line formed.  "Now," continued that particular Penton, "we will
each fire, beginning with myself, one at a time.  First ion, then
violet.  When one of us evidences lack of a serviceable gun, the
others will join in removing him rapidly but carefully.  Are we
ready?  Yes?"  That Penton held up his ion-gun and pushed the button.

It didn't fire, and immediately the portico stank with his smoke.

"That's one," said the next Penton.  He raised his ion-gun and fired.
Then his violet-gun.  Then he raised it and fired again at a rapidly
dissolving Blake.  "That makes two.  We have one more to eliminate.
Next?"

Presently another Blake vanished.  "Well, well," said Penton
pleasantly, "the Blake-Penton odds are even.  Any suggestions?"

"Yes," said Blake tensely.  "I've been thinking of a patch I put in
one suit that I ripped on Venus."  Another Blake vanished under the
mutual fire.

"There's one more thing I want to know.  Why in blazes are those
phonies so blasted willing to kill each other--and though they know
which is which don't kill us?  And how did they enter the ship?" Rod
demanded.

"They," said two Pentons at once.  Another one looked at them.  "Bad
timing, boys.  Rodney, my son, we used a combination lock.  These
gentlemen are professional mind-readers.  Does that explain their
possession of the guns?

"Now, since these little gun tests and others have been made, I think
it fairly evident that we are not going to leave this planet until
the two right men are chosen and only two go into that ship with us.
Fortunately they can't go without us--because while they can read
minds it takes more than knowledge to navigate a spaceship, at least
such knowledge as they can get from us.  It takes understanding,
which memory will not supply.  They need us.

"We will, therefore, march dutifully to the ship and each of us will
replace his guns carefully in the prepared racks.  _I_ know that
_I'm_ the right Penton--but _you_ don't.  So no movement will be made
without the agreement of all Pentons and Blakes."

Blake looked up, white-faced.  "If this wasn't so world-shakingly
serious it would be the damnedest comic opera that ever happened.
I'm afraid to give up my gun."

"If we all give them up I think it puts us even.  We have some
advantage in that they don't want to kill us.  And if worst comes to
worst we could take them to Earth, making damned sure that they
didn't get away.  On Earth we could have protoplasmic tests made that
would tell the story.  By the way, that suggests something.  I think
we can make tests here.  Let's repair to the ship."



The Blakes sat down and stayed down.  "Ted, what in blazes can we
do?"  His voice was almost tearful.  "You can't tell one of these
ghastly things from another.  You can't tell one from me.  We can't--"

"Oh Lord," said another Blake.  "That's not me.  That's just another
one of those damned mind-stealers."

Another one groaned hopelessly.  "That wasn't me either."  They all
looked helplessly at the line of Pentons.  "I don't even know who's
my friend."

Penton nodded.  All the Pentons nodded like a grotesquely solemn
chorus preparing to recite some blessing.  They smiled in superhuman
unity.  "That's all right," they said in perfect harmony.  "Well,
well.  A new stunt.  Now we all talk together.  That makes things
easier.

"I think there may be a way to tell the difference.  But you must
absolutely trust me, Blake.  You must give up your guns, putting
faith in my ability to detect the right one.  If I'm wrong, realize
that I will not know.  We can try such simple tests as alcohol,
whiskey, to see if it makes them drunk, and pepper to see if it burns
their tongues--"

"It won't work," said Blake.

Penton, all the Pentons smiled gently.  "I'm half again as fast as
you are, Blake, and no Martian-born imitation of you is going to be
faster.  Maybe these Martian imitations of me are as fast as I am.
But you know perfectly well that I could ray the whole gang of you,
all ten of you, out of existence before any one of you could move a
finger.  You know that, don't you, Rod?"

"Lord, yes.  But, Ted, don't do that--don't make me give up my guns.
Why should I give up mine if you keep yours?"

"That probably was not you speaking, Rod, but it doesn't matter.  If
it wasn't what you thought we could do something about it.
Therefore, that is what you wanted to say, just as this is what I
wanted to say, whether I said it or not.

"But anyway, the situation is this--one of us has to have
unquestioned superiority over the other gang.  Then the one with the
whip hand can develop proof of identity and enforce his decisions.
As it is, we can't."

"Let _me_ be that one then," snapped one Blake.

"I didn't mean that," sighed another.  "That wasn't me."

"Yes it was," said the first.  "I spoke without thinking.  Go ahead.
But how are you going to make the others give up their guns?  I'm
willing.  You can't make them."

"Oh yes I can.  I have my faithful friends, here," said Penton
grimly, his eleven hands waving to his eleven counterparts.  "They
agree with me this far, being quite utterly selfish."

"But what's your system?  Before I put my neck in the noose I have to
know that the noose isn't going to tighten on it."

"If I had a sound system in mind--I'm carefully refraining from
developing one--they'd read it, weigh it and wouldn't agree at all.
You see that pepper and alcohol system won't work perfectly because
they can read in my mind the proper reaction and be drunk or have an
inflamed tongue at will, being perfect actors.  I'm going to try just
the same.  Rod, if you ever trusted me, trust me now."

"All right, come on.  We'll go to the ship and any of these things
that doesn't part with its gun is not me.  Ray it."

Blake rose jerkily, all ten of him, and went down to the ship.

The Pentons followed faithfully.  Abruptly Penton rayed one Blake.
His shoulder blades had humped curiously and swiftly.  Wings were
developing.  "That helps," said Penton, bolstering his guns.

The Blakes went on, white-faced.  They put the weapons in the racks
in the lock stoically.  The Martians had seen the, to them,
inconceivably swift movements of Penton's gun hands and Penton knew
that he himself had done the raying that time.

But he still didn't know a way to prove it without causing a general
melee which would bring about their own deaths.  That wasn't so
important.  The trouble was that given fifty years the rest of the
world would descend on this planet unwarned.  Then all Earth would be
destroyed.  Not with flame and sword and horrible casualty lists--but
silently and undetectably.

The Blakes came out, unarmed.  They shuffled and moved about
uneasily, tensely, under the watchful eyes of eleven Pentons armed
with terrifically deadly weapons.

Several Pentons went into the ship, to come out bearing pepper,
saccharine tablets, alcohol, the medicine chest.  One of them
gathered them together and looked them over.  "We'll try pepper," he
said rather unhappily.  "Line up!"

The Blakes lined up, hesitantly.  "I'm putting my life in your hands,
Ted," said two of them in identical plaintive tones.

Four Pentons laughed shortly.  "I knew it.  Line up.  First, stick
out the tongue."

With unsteady hands he put a bit of pepper from the shaker on the
fellow's tongue.  The tongue snapped in instantly, the Blake clapped
his hands to his mouth, gurgling.  "Waaaar!" he gasped.
"Waar--achooo--damnt!"



With hands like flashing light Penton pulled his own and a neighbor's
ion-gun.  In a fiftieth of a second all but the single gagging
choking coughing Blake were stinking, smoking, swiftly dissolving and
flowing rubbish.  The other Pentons methodically helped destroy them.

Blake stopped gagging in surprise.  "My God, it might not have been
the right one!" he gasped.

The ten Pentons sighed softly.  "That finally proves it.  Thank
heaven.  Definitely.  That leaves me to find.  And it won't work
again because while you can't read my mind to find the trick that
told me these brothers of mine have.  The very fact that you don't
know how I knew proves that I was right."

Blake stared at him dumbly.  "I was the first one--"

"Exactly.  Go on inside.  Do something intelligent.  Use your head.
See what you can think of to locate me.  You have to use your head in
some such way that they don't mind-read it first though.  Go ahead."

Blake went, slow-footed.  The first thing he did was to close the
lock-door, so that he was safely alone in the ship.  Blake went into
the control room, donned an air-suit complete with helmet and pushed
a control handle over, then a second.

Presently he heard curious bumpings and thumpings and strange
floppings and whimperings.  He went back rapidly and rayed a supply
chest and two crates of Venusian specimens that had sprouted legs and
were rapidly growing arms to grasp ray pistols.  The air in the ship
began to look thick and greenish.  It was colder.

Contentedly Blake watched and opened all the room doors.  Another
slithering thumping noise attracted him and with careful violet-gun
work he removed an unnoticed extra pipe that was crawling from the
crossbrace hangers.  It broke up into lengths that rolled about
unpleasantly.  Rod rayed them till the smallest only, the size of
golf balls with curious blue-veined legs, staggered about
uncertainly.  Finally even they stopped wriggling.

Half an hour Rod waited while the air grew greener and thicker.
Finally to make sure he started some other apparatus and watched the
thermometer go down until moisture grew on the walls and became frost
and no more changes took place.  Then he went around with an opened
ion-gun with a needle beam and poked everything visible with it.

The suction fans cleared out the chlorine-fouled atmosphere in two
minutes and Blake sat down wearily.  He flipped over the microphone
switch and spoke into the little disc.  "I've got my hand on the main
ion-gun control.  Penton, I love you like a brother but I love Earth
more.

"If you can induce your boy friends to drop their guns in a neat pile
and retire--okay.  If not, and I mean if not within thirty seconds,
this ion-gun is going into action and there won't be any more
Pentons.  Now, drop!"

Grinning broadly with evident satisfaction ten Pentons deposited
twenty heart-cores of ultra-essence of destruction and moved off.
"Way off," said Blake grimly.  They moved.  Blake collected twenty
guns.  Then he went back into the ship.  There was a fine laboratory
at one end and with grim satisfaction he took down three
cotton-stoppered tubes, being very careful to handle them with rubber
gloves.  "You never did man a good turn before, tetanus, but I hope
you spread high, wide and handsome here--"

He dumped them into a beaker of water and took beaker and glass down
to the lock and out.  The ten waited at a distance.

"All right, Penton.  I happen to know you took a shot of tetanus
anti-vaccine some while ago and are immune.  Let's see if those
blasted brain-stealers can steal the secret of something we know how
to make but don't know anything about.  They can gain safety by
turning into chickens, which are immune, but not by remaining as
human creatures.  That's a concentrated dose of tetanus.  Go drink
it.  We can wait ten days if we have to."

The Pentons marched boldly up to the beaker, resting beside the ship.
One stepped forward to the glass--and nine kept right on stepping.
They stepped into the lee of the ship where the ion-gun could not
reach.

Blake helped Penton into the ship with a broad grin.  "Am I right?"

"You're right," sighed Penton, "but--you can't get tetanus by
swallowing it and lockjaw doesn't develop in ten days."

"I didn't know for sure."  Blake grinned.  "They were too busy trying
to find out what I was doing to follow your mind.  Ah--_there_ they
go.  Will you ray them or shall I?" asked Blake politely.

"There's one thing--ahhh"--he straightened as the incredible glare
died in thin air--"I want to know.  How in blazes did you pick _me_
out?"

"To do what you did requires some five hundred different sets of
muscles in a beautifully coordinated neuro-muscular hookup, which I
didn't believe those things could imitate without a complete
dissection.  I took the chance it was you."

"Five hundred sets of muscles!  What the heck did I do?"

"You sneezed."

Rod Blake blinked slowly and slowly his jaw tested again its supports
and their flexibility. * * *


[The end of _The Brain-Stealers of Mars_ by John W. Campbell, Jr.]