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    |                                                              |
    | Transcriber's note:                                          |
    |                                                              |
    | This story was published in _If: Worlds of Science Fiction_, |
    | November 1954. Extensive research did not uncover any        |
    | evidence that the U.S. copyright on this publication was     |
    | renewed.                                                     |
    |                                                              |
    +--------------------------------------------------------------+




_Illustrated by Kelly Freas_




The Hitch Hikers

    _The Rell, a great and ancient Martian race, faced extinction when
    all moisture was swept from their planet. Then, one day, a lone
    visitor--a strange, two-legged creature composed mostly of
    water--landed on Mars..._

BY VERNON L. MC CAIN


The dehydration of the planet had taken centuries in all. The Rell had
still been a great race when the process started. Construction of the
canals was a prodigious feat but not a truly remarkable one. But what
use are even canals when there is nothing to fill them?

What cosmic influences might have caused the disaster baffled even the
group-mind of the Rell. Through the eons the atmosphere had drifted into
space; and with it went the life-giving moisture. Originally a liquid
paradise, the planet was now a dry, hostile husk.

The large groups of Rell had been the first to suffer. But in time even
the tiny villages containing mere quadrillions of the submicroscopic
entities had found too little moisture left to satisfy their thirst and
the journey ever southward toward the pole had commenced.

The new life was bitter and difficult and as their resources were
depleted so also did their numbers diminish.

[Illustration]

Huddled at their last retreat the Rell watched the ever smaller ice cap
annually diminish and lived with the knowledge they faced extinction. A
mere thousand years more would see even this trifling remainder gone.

Oh, you might say there was hope ... of a sort. There might be Rell in
the northern hemisphere. The canals girdled the globe and a similar ice
cap could well exist at the opposite pole. Rell perhaps survived there
also.

But this was scant comfort. The fate of the Rell in the South was
sealed. What hope of any brighter future for those in the North? And if
they survived a few hundred thousand years longer ... or if they had
perished a similar period earlier, what actual difference did it make?

There was no one more aware of this gloomy future than Raeillo/ee13.

In the old days a single unit of the group-mind of the Rell would have
possessed but a single function and exercised this function perhaps a
dozen times during his life. But due to the inexorable shrinkage only
the most important problems now could command mind-action and each unit
had been forced to forsake specialization for multi-purpose endeavors.

Thus Raeillo/ee13 and his mate Raellu//2 were two of the five thousand
units whose task was to multiply in any group-mind action involving
mathematical prediction. Naturally Raeillo/ee13 and Raellu//2 did not
waste their abilities in mundane problems not involving prediction. Nor
did they divide, add, or subtract. That was assigned to other units just
as several million of the upper groups had the task of sorting and
interpreting their results. Raeillo/ee13 and Raellu//2 multiplied only.
And it must be admitted they did it very well. It is a pity the Rell
could not have multiplied physically as easily as Raeillo/ee13 and
Raellu//2 multiplied mentally.

With the exception of an occasional comet or meteor the Rell were seldom
diverted by anything of a physical nature. The ice cap was their sole
concern.

But one afternoon a rare physical phenomenon was reported by a bank of
observer Rell.

"In the sky's northwest portion," an excited injunction came through.
"Observe that patch of flaming red!"

More observer Rell were quickly focused on the novel sight and further
data was rapidly fed into the interpretive bank.

The Rell were justifiably proud of their interpreters. With the race
shrinkage it had proved impossible to properly train new interpreters.
So, not without a great deal of sacrifice, the old interpreters, dating
back to when the canals still flowed with water, had been kept alive.

They were incredibly ancient but there was no doubt as to their ability.
It was a truism among the Rell that the interpretive banks arrived at
their conclusions faster than any other group and that these conclusions
could be checked to hundreds of decimal places without finding
inaccuracy.

So it was no surprise to have the interpretive bank respond almost
instantly, "It is quite odd but the flame appears to be of artificial
origin."

"Artificial!" came the rough and questing probe of the speculative bank.
"But how could Rell possibly be out there?"

"Who mentioned Rell?" was the interpretive bank's smug answer. They were
not utterly averse to demonstrating their superior mental abilities on
occasion.

The speculative bank replied, "Artificial implies intelligence, and
intelligence means Rell..."

"Does it?" the interpretive bank interrupted. The speculative bank
waited but the interpretive bank failed to enlarge on the provocative
query.

The Rell had found certain disadvantages accrued to abnormal
prolongation of life and thus were not unused to the interpretive bank's
occasional tendency to talk in riddles.

"Perhaps not," the speculative bank replied after a quick check with the
logical formulae held in reserve by the historical bank. "It is
theoretically possible that Rell-like individuals might have developed
elsewhere, and perhaps even have developed intelligence, although,
according to the historical bank, such an idea has never before been
subjected to consideration. But what is the flame doing?" they
continued, a trifle resentful at having been left to do work properly in
the interpretive bank's province.

The observation and interpretive banks once more came into play,
studying the situation for several minutes. "The flame appears to be the
exhaust of a fairly crude vessel," the interpretive bank finally
reported, "propelled by ignition of some gaseous mixture."

"Is it moving?"

"Quite rapidly."

"Where is it going?"

This called into play the prophecy division of the mind and Raeillo/ee13
and Raellu//2, who had been merely interested onlookers before,
hurriedly meshed themselves with the other forty nine hundred odd of
their fellows. (It was impossible to say at any given time just how many
there were in their computer section, as several births and deaths had
occurred among the group since beginning the current observations. These
would be suspended for the next several moments, however, as there was a
strict prohibition against anyone being born, dying, or otherwise
engaging in extraneous activity while their particular bank was either
alerted or in action.)

Raeillo/ee13 and Raellu//2 felt the group discipline take hold much more
firmly than the free-and-easy mesh which each unit enjoyed with the
complete group-mind during periods of leisure.

With a speed that would have been dizzying and incomprehensible to any
individual unit, the observing banks relayed huge masses of extraneous
data to the interpretive bank. They strained out the salient facts and
in turn passed these to the computing:prediction section. Here they were
routed to the groups who would deal with them. Raeillo/ee13 and Raellu//2
found their own talents pressed into service a dozen or more times in
the space of the minute and a half it took the computing:prediction and
interpretive banks to arrive at the answer.

"It's aimed here," the interpretive bank reported.

"Here!" a jumble of incoherent and anarchistic thoughts resounded from
many shocked and temporarily out-of-mesh units.

"Order!" came a sharp command from the elite corp of three thousand
disciplinary units.

As stillness settled back over the group-mind the speculative bank once
more came in. "By here ... do you mean _right_ here?"

"Approximately," replied the interpretive bank with what would have
sounded suspiciously like a chuckle in a human reply. "According to
calculations the craft should land within half a mile of our present
location."

"Let's go there then and wait for it!" That thought from the now seldom
used reservation of impulse.

The speculative bank murmured, "I wonder if there would be any danger.
How hot is that exhaust?"

Calculations were rapidly made and the answer arrived at. The Rell
prudently decided to remain where they were for the present.

       *       *       *       *       *

Captain Leonard Brown, USAF, hunched over the instruments in the cramped
control cabin which, being the only available space in the ship, doubled
as living quarters. A larger man would have found the arrangement
impossible. Brown, being 5' 2" and weighing 105 pounds found it merely
intolerable.

At the moment he was temporarily able to forget his discomfort, however.
The many tiny dials and indicators told a story all their own to Brown's
trained vision.

"Just another half hour," he whispered to himself. "Just thirty more
minutes and I'll land. It may be just a dead planet but I'll still be
the first."

There really wasn't a great deal for Brown to do. The ship was
self-guided. The Air Force had trusted robot mechanisms more than human
reactions.

Thus Brown's entire active contribution to the flight consisted in
watching the dials (which recorded everything so even watching them was
unnecessary) and in pressing the button which would cause the ship to
start its return journey.

Of course the scientists could have constructed another mechanism to
press the button and made it a completely robot ship. But despite their
frailties and imperfections, human beings have certain advantages.
Humans can talk. Machines may see and detect far more than their human
creators but all they can do is record. They can neither interpret nor
satisfactorily describe.

Brown was present not only to report a human's reactions to the first
Mars flight; he was also along to see that which the machines might
miss.

"We've never satisfactorily defined life," one of his instructors had
told Brown shortly after he started the three grueling years of training
which had been necessary, "so we can't very well build a foolproof
machine for detecting it. That's why we've left room for 105 pounds of
dead weight."

"Meaning me?"

"Meaning you."

"And I'm your foolproof machine for detecting life?"

"Let's say you're the closest we can come to it at present. We're
banking everything on this first trip. It'll be at least eighteen
months later before we can get a second ship into space. So it's up to
you to get everything you can ... some evidence of life, preferably
animal, if possible. With public support it'll be a hell of a lot easier
squeezing appropriations out of Congress for the next ship and to get
public support we need the biggest possible play in the newspapers. If
anything is newsworthy on Mars it should be evidence of life ... even
plant life."

So here he was, 105 pounds of concentrated knowledge and anticipation,
itching with the desire for action and also from more basic causes
having to do with two months confinement in a small space with a minimum
of water.

"Life is most probable at the poles," the instructor had said. "You
won't be able to stay long so we'll try to set you down right at the
South Pole. You won't have room to bring back specimens. So keep your
eyes open and absorb everything you see. Don't forget anything. What you
bring back in your mind weighs nothing."


"It's just sitting there," the observing banks reported, "and the red
flame has gone out."

"Is it safe now?" enquired the speculative bank.

"In what way?"

"Is it safe to go near that thing?"

"It's very huge," ventured the observing banks unasked. There was a stir
of activity which encompassed practically all except the most simple
units and which lasted for perhaps five minutes while the speculative
bank's last question was processed.

Finally the interpretive bank reluctantly admitted, "We can't arrive at
a positive answer. Too many unknown elements are present. We don't know
for sure what caused the flame, when it might start again, or what, if
anything, is inside."

"But you said it was a work of intelligence. Doesn't that mean Rell
would be inside?"

"Not necessarily. They could have constructed the thing to operate
itself."

It was just then that the observing banks reported, "It's opening."

The speculative bank quickly responded, "This is an emergency. We must
be able to observe from close up. We'll have to approach it."

"The entire mind?" enquired the disciplinary corps.

The speculative bank hesitated. "No, we'll need to split up. One-fifth
of us will go, the rest remain here. It's a short distance and we'll
still be able to continue in complete contact."

Those who were to go were quickly sorted out and Raeillo/ee13 was quite
thrilled to find he and Raellu//2 were included in the scouting party.

The group set off briskly toward their objective but had moved hardly
one hundred yards when a vertigo seemed to overtake them. Raeillo/ee13
found himself swimming helplessly in a vortex of darkness and isolation,
blanked off from not only the group-mind and his bank but also from
Raellu//2. Frantically he grasped for some sort of stasis, but
dependence on the group-mind was too ingrained and he was unable to stir
his long-dormant powers of sight and education.

Then the isolation cleared to be replaced by a brief impression of chaos
with perhaps a tinge of alienness. Another instant of vertigo followed
and then everything was normal once more as the comfortable familiar
mesh took hold.

"What was that?" Even the speculative bank sounded frightened.

"Sorry." The usually silent meshing bank sounded abashed. "We weren't
prepared for that. Some sort of thought wave is issuing from the opening
and it disrupted the group mesh till we were able to take it into
calculation and rebuild the mesh around it."

"Thought wave? Then there _are_ Rell in that thing."

"Do not compute before the mesh is set," the interpretive bank
cautioned. "The presence of Rell, while extremely probable, is not yet
entirely certain."

Without waiting for a suggestion from elsewhere the disciplinary group
ordered the entire mind forward.

Perhaps, in time of stress, dormant qualities tend to emerge,
Raeillo/ee13 mused. Certainly everyone, himself included, appeared to be
exercising speculative qualities. Not that specialization isn't a
marvelous blessing, he hastily added, in case the disciplinary corps
might be scanning his bank. But the disciplinary corps itself was as
fascinated by the phenomenon ahead as Raeillo/ee13.

Emerging from the infinitely huge upright thing was a mobile being, also
infinitely huge. Not that they were the same size. The mobile one was
small enough to fit easily through the opening in the lower portion of
the larger. But beyond a certain point words lose meaning and infinitely
huge was the closest measurement the tiny Rell could find for either the
upright pointed thing or the knobby one which had emerged and was
quickly identified as the source of the disrupting thought patterns.

       *       *       *       *       *

Leonard Brown was enjoying himself thoroughly. The inside of a space
suit can scarcely be termed comfortable but at least you can move around
in it and Brown was making the most of this sensation after two months
cramped in his tiny cell. He was, in fact, comporting himself much as a
three-year-old might have done after a similar release.

But before long he settled down to the serious business of observing and
mentally recording everything in sight.

There were none of the mysterious 'canals' in view, which was
disappointing; one piece of glamour the publicity boys would necessarily
forego until the next trip. The ice cap itself, if such it could be
called, was almost equally disappointing. On Earth it would have been
dismissed as a mere frost patch, if this section was typical. For a
radius of many yards the ground was blasted bare by the action of the
exhaust and nowhere in sight did there appear to be more than the
flimsiest covering of white over the brown sandy soil.

"Not even lichens," muttered Brown in disgust.

But disgust cannot long stand against the magic of a fresh new planet
and Brown continued his avid, though barren, search until hunger forced
his return to the ship. He had been able to detect no life and was
completely unaware of his close proximity to the planet's dominant
species. It had been considered neither practical nor particularly
desirable to build a microscope into the space suit. Simplicity and the
least possible weight had been the watchwords here as with everything
designed to go aboard the ship.

In any case, a microscope would have done Brown little good in trying to
detect the submicroscopic beings of the Rell.


The Rell, who had somewhat lost their fear of Brown, hastily retreated
when they saw him returning to the still awesome ship.

"But are you _sure_ he's _completely_ self-powered?" the speculative
bank queried. "No Rell inside him at all?"

"There are many Rell-like beings in various parts of him," replied the
interpretive bank. "Some help digest his food, others are predators, and
still others their enemies. But most are too big and clumsy to have
developed intelligence, and even the small ones appear completely
mindless."

"But where do the thought waves come from? We all felt them."

"It's hard to accept but we are almost forced to conclude they are
emanating from the mobile unit itself, or rather from the living part
within the cocoon."

"You're positive they aren't the product of some of the Rell-beings
inside?"

"Almost positive. The mesh insists not. In fact, it claims this is an
un-Rell like type of intelligence, though that appears to be a
contradiction in terms. The thought pattern is completely outside our
experience. In fact, it is so alien we haven't broken it down yet to the
meaning behind it."

"But if the Rell inside are too large to have developed intelligence,
how could this gigantic monster in which they live have done so?"

"We cannot yet say. Remember, the theory that intelligence cannot
develop in creatures above a certain size is unproven, even though never
before challenged. We've watched other races die through failure to
adapt to change so apparently it is true of Rell-like creatures on this
world. But who can say about organisms on another world or of the
unprecedented size of this one? Completely different physical laws may
apply."

It was later that afternoon after the Rell had spent much time observing
Brown while Brown was busy observing the landscape that the interpretive
bank made the triumphant announcement, "We have it! We've broken the
thought waves down to their meanings and know what he's thinking. What
would you like to know first?"

"Check and see if there are any Rell inside the other thing or on his
home world. They might have constructed him."

"Apparently there are none, or at least no intelligent Rell, on his
world. We can't guide his mind but the memory bank recorded all the
thoughts we've received and some time ago he was thinking of something
he termed 'vermin'. Apparently these are sometimes Rell-like creatures,
although far larger. He regards them as a great nuisance, but mindless.
The big thing, by the way, he calls a 'ship' and it is utterly lifeless.
We needn't fear the flame until this creature leaves."

"What about him? What is he like?"

"That's the most exciting part! He thought of his bodily needs once and
we glimpsed a concept dealing with his physical construction. It's
incredible! His body is composed almost entirely of water ... there's
enough water in him alone to prolong the life of the Rell many ages.
Further, the air in his 'ship' is heavily impregnated with moisture and
he even has reserve supplies of water for his needs."


At this, not only Raeillo/ee13, but all except perhaps the most
responsible units felt a shiver of primitive longing and perhaps even
greed. Not for millennia had there been such a plentitude of water so
close!

"Then can't we appropriate at least part of it?" asked the speculative
bank.

"Unfortunately both the 'man', as he calls himself, and his 'ship' are
sealed so tightly that we could not penetrate either. Worse yet, almost
half his time here is already gone. We don't quite understand his
purpose here. His thoughts seem to say he is searching for Rell for some
unfathomable reason yet he seems to know nothing of the Rell and cannot
even detect us."

       *       *       *       *       *

It was the next day when the time was almost all gone that the two big
discoveries were made. During a routine check, the mesh came across a
thought of the man's return and a visualization of his home world. It
was so startling that the interpretive bank was recalled from its effort
to try to devise a means through the spacesuit and set at the new
problem.

A hasty check of the man's subconscious thoughts revealed the big news.
"Do you know," the interpretive bank announced, "not only does this
being's home world have a moist atmosphere like that in his ship but two
thirds of the surface of his world is _liquid water_!"

Even the speculative bank was silent for a full two seconds after this
news. Then a hasty impulse was sent to the disciplinary corps and the
entire mind called into action. An extreme emergency upon which the fate
of the race hinged called for the utmost effort by even the humblest
members of the group.

The Rell worked diligently and many blind alleys were explored, but it
was not for some time that anyone thought of enquiring of the
not-too-bright feeding bank how they were managing to keep the mind
operating at considerably more than normal power with no frost within
feeding distance.

"We're taking moisture from the air," was the answer.

"Where is the moisture coming from?" the interpretive bank was asked.

The answer didn't take long. Rapid measurements supplied it. "Some of it
is vaporized frost but that wouldn't be enough for our needs. The only
other possibility is that moisture must be seeping away from either the
man or his ship despite his sureness that they were both airtight and
our own investigations which confirmed it."

They had maintained a cautious distance from the ship for the most part
despite the interpretive bank's assurance of no immediate danger. But
now they swarmed over both it and the spacesuit determined to detect the
leak.

They found none.

And now the man was returning to his ship.

"This is the last time," the mesh warned. It was now or never.

For a second there was conflict over control of the circuits to the
disciplinary corps which carried with it command of the organism during
the emergency. The speculative bank customarily assumed this
responsibility, but a slight schism had developed between it and the
interpretive bank. The latter's greater age and skill came into play and
victory was quickly won.

From the disciplinary corps came the order, "Stay close to the 'man'."

The interpretive bank explained, "He breathes the air so he'll have to
get to it some way."

The defeated speculative bank maintained a sulky silence.

Thus it was that the entire mind of the Rell rode into the interior of
the ship through the airlock while clustered around Brown.

The Rell had grasped that the man lived and traveled inside his ship and
the necessity for it to be airtight. But so desperate were the two
races' needs that the necessity for an airlock and the consequent slight
seepage each time it was used had not occurred to even the interpretive
bank.

Inside, many Rell, suddenly intoxicated by the heady moisture-laden air,
commenced uniting with each other then splitting away, each such union
resulting in another unit of Rell, naturally. The interpretive bank
again seized control.

"Stop it! Stop it this instant!" it snapped. "Reproduction must be kept
to the former minimum for now. That is a firm order."

Reluctantly the process was halted. The interpretive bank explained, "It
would not take long for us to use up the entire supply of water if we
indulged in uncontrolled reproduction. That might endanger the whole
trip."

"What do we do now?" the speculative bank finally asked.

"There is no way of knowing positively whether the man uses this same
atmosphere until he returns to his world or not. For our own safety it
would seem best, since Rell-like creatures already inhabit him, that we
join them. If any place is safe it will be his interior. And there is
plenty of moisture within to sustain us. But we must be good parasites,"
the interpretive bank warned. "Remember, no undue reproduction no matter
how many quarts of moisture seem to be going to waste inside this 'man'.
He may need it himself and if he does not survive the ship might not
complete its trip."

Brown was just emerging from his space suit so the Rell chose his
closest available body opening and flowed as a group into his mouth and
nostrils.

"Ahchoo!" sneezed Brown, violently evicting half the Rell.

They re-entered a bit more cautiously in order not to irritate the
sensitive membrane again.

"Dammit," said Brown, "don't tell me I've caught a cold clear out here
on Mars. Hope I didn't pick up any Martian germs."

But he needn't have worried. By the time he reached Earth he was far
less germ-ridden, even if considerably more itchy on the exterior, than
when he'd left. The Rell were good at self defense and a surprising
number of mindless but voracious creatures in Brown's interior had been
eliminated.

Brown dreaded having to give the news he carried but he needn't have. He
was a conquering hero.

So much fuss was made over the first flight to Mars that Congress
promptly voted twice the appropriation for the second ship that the Air
Force had requested, despite strong opposition from the Navy and
headlines which read:

    NO LIFE ON MARS

Actually, as it happened, the headlines were one hundred percent
correct, but they neglected to mention, chiefly because the headline
writers didn't know it, that there were now two races of intelligent
life on Earth.