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    THREE AGAINST THE STARS

    A sky pirate armed with superior weapons of his own
    invention....

    First contact with an alien race dangerous enough to
    threaten the safety of two planets....

    The arrival of an unseen dark sun whose attendant
    marauders aimed at the very end of civilization in this
    Solar System....

    These were the three challenges that tested the skill
    and minds of the brilliant team of scientist-astronauts
    Arcot, Wade, and Morey. Their initial adventures are a
    classic of science-fiction which first brought the name
    of their author, John W. Campbell, into prominence as a
    master of the inventive imagination.



    JOHN W. CAMPBELL first started writing in 1930 when his
    first short story, _When the Atoms Failed_, was
    accepted by a science-fiction magazine. At that time he
    was twenty years old and still a student at college. As
    the title of the story indicates, he was even at that
    time occupied with the significance of atomic energy
    and nuclear physics.

    For the next seven years, Campbell, bolstered by a
    scientific background that ran from childhood
    experiments, to study at Duke University and the
    Massachusetts Institute of Technology, wrote and sold
    science-fiction, achieving for himself an enviable
    reputation in the field.

    In 1937 he became the editor of _Astounding Stories_
    magazine and applied himself at once to the task of
    bettering the magazine and the field of s-f writing in
    general. His influence on science-fiction since then
    cannot be underestimated. Today he still remains as the
    editor of that magazine's evolved and redesigned
    successor, _Analog_.



THE BLACK STAR PASSES

JOHN W. CAMPBELL





ACE BOOKS, INC.
1120 Avenue of the Americas
New York, N.Y. 10036





THE BLACK STAR PASSES

Copyright, 1953, by John W. Campbell, Jr.

Copyright, 1930, by Experimenter Publications, Inc.

An Ace Book, by arrangement with the author.


_Cover art by Jerome Podwil._



Printed in U.S.A.





Contents


Introduction 7


BOOK ONE

Piracy Preferred 11


BOOK TWO

Solarite 71


BOOK THREE

The Black Star Passes 145


[Illustration]




INTRODUCTION


These stories were written nearly a quarter of a century ago, for the
old _Amazing Stories_ magazine. The essence of any magazine is
not its name, but its philosophy, its purpose. That old _Amazing
Stories_ is long since gone; the magazine of the same name today is
as different as the times today are different from the world of 1930.

Science-fiction was new, in 1930; atomic energy was a dream we
believed in, and space-travel was something we tried to understand
better. Today, science-fiction has become a broad field, atomic
energy--despite the feelings of many present adults!--is no dream.
(Nor is it a nightmare; it is simply a fact, and calling it a
nightmare is another form of effort to push it out of reality.)

In 1930, the only audience for science-fiction was among those who
were still young enough in spirit to be willing to hope and speculate
on a new and wider future--and in 1930 that meant almost nothing but
teen-agers. It meant the brightest group of teen-agers, youngsters who
were willing to _play_ with ideas and understandings of physics
and chemistry and astronomy that most of their contemporaries
considered "too hard work."

I grew up with that group; the stories I wrote over the years, and,
later, the stories I bought for _Astounding Science Fiction_
changed and grew more mature too. _Astounding Science Fiction_
today has many of the audience that read those early stories; they're
not high school and college students any more, of course, but
professional engineers, technologists and researchers now. Naturally,
for them we need a totally different kind of story. In growing with
them, I and my work had to lose much of the enthusiastic scope that
went with the earlier science fiction.

When a young man goes to college, he is apt to say, "I want to be a
scientist," or "I want to be an engineer," but his concepts are broad
and generalized. Most major technical schools, well knowing this, have
the first year course for _all_ students the same. Only in the
second and subsequent years does specialization start.

By the sophomore year, a student may say, "I want to be a
_chemical_ engineer."

At graduation, he may say, "I'm going into chemical engineering
_construction_."

Ten years later he may explain that he's a chemical engineer
specializing in the construction of corrosion-resistant structures,
such as electroplating baths and pickling tanks for stainless steel.

Year by year, his knowledge has become more specialized, and much
deeper. He's better and better able to do the important work the world
needs done, but in learning to do it, he's necessarily lost some of
the broad and enthusiastic scope he once had.

These are early stories of the early days of science-fiction. Radar
hadn't been invented; we missed that idea. But while these stories
don't have the finesse of later work--they have a bounding enthusiasm
that belongs with a young field, designed for and built by young men.
Most of the writers of those early stories were, like myself, college
students. (_Piracy Preferred_ was written while I was a sophomore
at M.I.T.)

For old-timers in science-fiction--these are typical of the
days when the field was starting. They've got a fine flavor
of our own younger enthusiasm.

For new readers of science-fiction--these have the stuff that laid the
groundwork of today's work, they're the stories that were meant for
young imaginations, for people who wanted to think about the world
they had to build in the years to come.

Along about sixteen to nineteen, a young man has to decide what is,
for him, the Job That Needs Doing--and get ready to get in and pitch.
If he selects well, selects with understanding and foresight, he'll
pick a job that _does_ need doing, one that will return rewards
in satisfaction as well as money. No other man can pick that for him;
he must choose the Job that _he_ feels fitting.

Crystal balls can be bought fairly reasonably--but they don't work
well. History books can be bought even more cheaply, and they're
moderately reliable. (Though necessarily filtered through the cultural
attitudes of the man who wrote them.) But they don't work well as
predicting machines, because the world is changing too rapidly.

The world today, for instance, needs engineers desperately. There a
lot of jobs that the Nation would like to get done that can't even be
started; not enough engineers available.

Fifty years ago the engineering student was a sort of Second Class
Citizen of the college campus. Today the Liberal Arts are fighting for
a come-back, the pendulum having swung considerably too far in the
other direction.

So science-fiction has a very real function to the teen-agers; it
presents varying ideas of what the world in which he will live his
adult life will be interested in.

This is 1953. My son will graduate in 1955. The period of his peak
earning power should be when he's about forty to sixty--about 1970,
say, to 1990. With the progress being made in understanding of health
and physical vigor, it's apt to run beyond 2000 A.D., however.

Anyone want to bet that people will be living in the same general
circumstances then? That the same general social and cultural and
material standards will apply?

I have a hunch that the history books are a poor way of planning a
life today--and that science-fiction comes a lot closer.

There's another thing about science-fiction yarns that is quite
conspicuous; it's so difficult to pick out the villains. It might have
made quite a change in history if the ballads and tales of the old
days had been a little less sure of who the villains were. Read the
standard boy's literature of forty years ago; tales of Crusaders who
were always right, and Saracens who were always wrong. (The same
Saracens who taught the Christians to respect the philosophy of the
Greeks, and introduced them to the basic ideas of straight,
self-disciplined thinking!)

Life's much simpler in a thatched cottage than in a dome on the
airless Moon, easier to understand when the Villains are all pure
black-hearted villains, and the Heroes are all pure White Souled
Heroes. Just look how simple history is compared with science-fiction!
It's simple--but is it good?

These early science-fiction tales explored the Universe; they were
probings, speculations, as to where we _could_ go. What we
_could_ do.

They had a sweep and reach and exuberance that belonged.

They _were_ fun, too....

John W. Campbell, Jr.
Mountainside, N.J.
April, 1953




BOOK ONE

PIRACY PREFERRED




PROLOGUE


High in the deep blue of the afternoon sky rode a tiny speck of
glistening metal, scarcely visible in the glare of the sun. The workers
on the machines below glanced up for a moment, then back to their work,
though little enough it was on these automatic cultivators. Even this
minor diversion was of interest in the dull monotony of green. These
endless fields of castor bean plants had to be cultivated, but with the
great machines that did the work it required but a few dozen men to
cultivate an entire county.

The passengers in the huge plane high above them gave little thought to
what passed below, engrossed with their papers or books, or engaged in
casual conversation. This monotonous trip was boring to most of them. It
seemed a waste of time to spend six good hours in a short 3,500 mile
trip. There was nothing to do, nothing to see, except a slowly passing
landscape ten miles below. No details could be distinguished, and the
steady low throb of the engines, the whirring of the giant propellers,
the muffled roar of the air, as it rushed by, combined to form a
soothing lullaby of power. It was all right for pleasure seekers and
vacationists, but business men were in a hurry.

The pilot of the machine glanced briefly at the instruments, wondered
vaguely why he had to be there at all, then turned, and leaving the
pilot room in charge of his assistant, went down to talk with the chief
engineer.

His vacation began the first of July, and as this was the last of June,
he wondered what would have happened if he had done as he had been half
inclined to do--quit the trip and let the assistant take her through. It
would have been simple--just a few levers to manipulate, a few controls
to set, and the instruments would have taken her up to ten or eleven
miles, swung her into the great westward air current, and leveled her
off at five hundred and sixty or so an hour toward 'Frisco'. They would
hold her on the radio beam better than he ever could. Even the landing
would have been easy. The assistant had never landed a big plane, but he
knew the routine, and the instruments would have done the work. Even if
he hadn't been there, ten minutes after they had reached destination, it
would land automatically--if an emergency pilot didn't come up by that
time in answer to an automatic signal.

He yawned and sauntered down the hall. He yawned again, wondering what
made him so sleepy.

He slumped limply to the floor and lay there breathing ever more and
more slowly.

       *       *       *       *       *

The officials of the San Francisco terminus of The Transcontinental
Airways company were worried. The great Transcontinental express had
come to the field, following the radio beam, and now it was circling the
field with its instruments set on the automatic signal for an emergency
pilot. They were worried and with good reason, for this flight carried
over 900,000 dollars worth of negotiable securities. But what could
attack one of those giant ships? It would take a small army to overcome
the crew of seventy and the three thousand passengers!

The great ship was landing gently now, brought in by the emergency
pilot. The small field car sped over to the plane rapidly. Already the
elevator was in place beside it, and as the officials in the car drew up
under the giant wing, they could see the tiny figure of the emergency
pilot beckoning to them. Swiftly the portable elevator carried them up
to the fourth level of the ship.

What a sight met their eyes as they entered the main salon! At first
glance it appeared that all the passengers lay sleeping in their chairs.
On closer examination it became evident that they were not breathing!
The ear could detect no heartbeat. The members of the crew lay at their
posts, as inert as the passengers! The assistant pilot sprawled on the
floor beside the instrument panel--apparently he had been watching the
record of the flight. There was no one conscious--or apparently
living--on board!

"Dead! Over three thousand people!" The field manager's voice was
hoarse, incredulous. "It's impossible--how could they have done it? Gas,
maybe, drawn in through the ventilator pumps and circulated through the
ship. But I can't conceive of any man being willing to kill three
thousand people for a mere million! Did you call a doctor by radio,
Pilot?"

"Yes, sir. He is on his way. There's his car now."

"Of course they will have opened the safe--but let's check anyway. I can
only think some madman has done this--no sane man would be willing to
take so many lives for so little." Wearily the men descended the stairs
to the mail room in the hold.

The door was closed, but the lock of the door was gone, the
magnesium-beryllium alloy burned away. They opened the door and entered.
The room seemed in perfect order. The guard lay motionless in the steel
guard chamber at one side; the thick, bullet-proof glass made his
outlines a little blurred, and the color of his face was green--but they
knew there too must be that same pallor they had seen on the other
faces. The delicate instruments had brought in the great ship perfectly,
but it was freighted with a cargo of dead!

They entered the room and proceeded to the safe, but it was opened as
they had expected. The six-inch tungsto-iridium wall had been melted
through. Even this unbelievable fact no longer surprised them. They
only glanced at the metal, still too hot to touch, and looked about the
room. The bonds had been taken. But now they noticed that over the
mail-clerk's desk there had been fastened a small envelope. On it was
printed:

    To the Officials of the San Francisco Airport

Inside was a short message, printed in the same sharp, black letters:

    Gentlemen:

    This plane should land safely. If it doesn't, it is your
    fault, not mine, for the instruments that it carries
    should permit it. The passengers are NOT dead! They have
    been put in a temporary state of suspended animation.
    Any doctor can readily revive them by the injection of
    seven c.c. of decinormal potassium iodide solution for
    every 100 pounds of weight. Do NOT use higher
    concentrations. Lower concentrations will act more
    slowly.

    You will find that any tendency toward leprosy or cancer
    will have been destroyed. It will kill any existing
    cancer, and cure it in about one week. I have not
    experimented with leprosy beyond knowing that it is
    cured very quickly.

    This is an outside job. Don't annoy the passengers with
    questions.

    The gas used cannot be stopped by any material I know
    of. You can try it with any mask--but don't use the
    C-32L. It will react with the gas to kill. I would
    advise that you try it on an animal to convince
    yourselves.

    I have left stock in my new company to replace the bonds
    I have taken.

    Piracy Incorporated is incorporated under my own laws.

                                                  The Pirate

On the desk beneath the note was a small package which contained a
number of stock certificates. They totalled $900,000 face value of
"Piracy Preferred", the preferred stock of a corporation, "Piracy, Inc."

"Piracy! Pirates in the air!" The field manager forced an unnatural
laugh. "In 2126 we have pirates attacking our air lines. _Piracy
Preferred!_ I think I'd prefer the bonds myself. But thank God he did
not kill all those people. Doctor, you look worried! Cheer up. If what
this pirate says is true, we can resuscitate them, and they'll be better
off for the experience!"

The doctor shook his head. "I've been examining your passengers. I'm
afraid that you'll never be able to bring these people back to life
again, sir. I can't detect any heart action even with the amplifier.
Ordinary heart action sounds like a cataract through this instrument. I
can see nothing wrong with the blood; it has not coagulated as I
expected, nor is there any pronounced hydrolysis as yet. But I'm afraid
I'll have to write out the death warrants for all these men and women.
One of the people on that ship was coming to see me. That's how I
happened to be on the field. For her, at least, it may be better so. The
poor woman was suffering from an incurable cancer."

"In this case, Doctor, I hope and believe you are wrong. Read this
note!"

       *       *       *       *       *

It was two hours before the work of reviving the passengers could be
started. Despite all the laws of physics, their body temperature had
remained constant after it had reached seventy-four, showing that some
form of very slow metabolism was going on. One by one they were put into
large electric blankets, and each was given the correct dose of the
salt. The men waited anxiously for results--and within ten minutes of
the injection the first had regained consciousness!

The work went forward steadily and successfully. Every one of the
passengers and crew was revived. And the Pirate had spoken the truth.
The woman who had been suffering from cancer was free from pain for the
first time in many months. Later, careful examination proved she was
cured!

The papers were issuing extras within five minutes of the time the great
plane had landed, and the radio news service was broadcasting the first
"break" in a particularly dead month. During all of June the news had
been dead, and now July had begun with a bang!

With time to think and investigate, the airport officials went over the
ship with the Air Guard, using a fine-tooth comb. It was soon evident
that the job had been done from the outside, as the Pirate had said. The
emergency pilot testified that when he entered the ship, he found a
small piece of wire securing the air lock from the outside. This had
certainly been put on while the ship was in flight, and that meant that
whoever had done this, had landed on the great ship with a small plane,
had somehow anchored it, then had entered the plane through the air lock
at the ten mile height. He had probably flown across the path of the
plane, leaving a trail of gas in its way to be drawn in through the
ventilator pumps. It had been washed out by the incoming good air later,
for the emergency pilot had not been affected.

Now the investigation led them to the mail-room. Despite the refractory
nature of the metal, the door had been opened by melting or burning out
the lock. And an opening had been burned into the safe itself! Opened by
melting it through!

A bond shipment was due the next day, and the airline officials planned
to be on the watch for it. It would get through safely, they were sure,
for men were put on board in steel chambers hermetically welded behind
them, with oxygen tanks and automatic apparatus sealed within to supply
them with clean air. The front of the tanks were equipped with
bullet-proof glass windows, and by means of electrically operated
controls the men inside could fire machine guns. Thus they were
protected from the Pirate's gas and able to use their weapons.

The ship was accompanied by a patrol of Air Guardsmen. Yet, despite,
this, cancer cases were aboard with the hope of being gassed.

When the plane reached the neighborhood of San Francisco, there had been
no sign of an attack. The Pirate might well retire permanently on a
million, if he were alone, as the singular signature indicated; but it
seemed much more probable that he would attempt another attack in any
case. Well, that just meant watching all the planes from now on, a
tremendous job for the Air Guard to handle.

The leader of the patrol turned in an easy bank to descend the ten miles
to Earth, and his planes followed him. Then suddenly through the
communicator came an unmistakable sound. _The plane automatically
signaling for an emergency pilot!_ That could only mean that the plane
had been gassed under the very eyes of his men!

The bonds were gone and the passengers gassed, and incredibly, the men
in the steel tanks were as thoroughly gassed as the rest.

The note was brief, and as much to the point as was the absence of the
bonds.


    To the Officials of the Airport:

    Restore as usual. The men in the tanks are asleep
    also--I said the gas would penetrate _any_ material. It
    does. A mask obviously won't do any good. Don't try that
    C-32L mask. I warn you it will be fatal. My gas reacts
    to produce a virulent poison when in contact with the
    chemicals in the C-32L.

                                                  The Pirate




I.


On the thirty-ninth floor of a large New York apartment two young men
were lounging about after a strenuous game of tennis. The blue tendrils
of smoke from their pipes rose slowly, to be drawn away by the efficient
ventilating system. The taller of the two seemed to be doing most of the
talking. In the positions they had assumed it would have been rather
difficult to be sure of which was the taller, but Robert Morey was a
good four inches taller than Richard Arcot. Arcot had to suffer under
the stigma of "runt" with Morey around--he was only six feet tall.

The chosen occupation of each was physical research, and in that field
Arcot could well have called Morey "runt", for Arcot had only one
competitor--his father. In this case it had been "like father, like
son". For many years Robert Arcot had been known as the greatest
American physicist, and probably the world's greatest. More recently he
had been known as the father of the world's greatest physicist. Arcot
junior was probably one of the most brilliant men the world had ever
seen, and he was aided in all his work by two men who could help him in
a way that amplified his powers a thousand fold. His father and his best
friend, Morey, were the complimentary and balancing minds to his great
intelligence. His father had learned through years of work the easiest
and best ways of performing the many difficult feats of laboratory
experimentation. Morey could develop the mathematical theory of a
hypothesis far more readily than Arcot could. Morey's mind was more
methodical and exact than Arcot's, but Arcot could grasp the broad
details of a problem and get the general method of solution developed
with a speed that made it utterly impossible for his friend even to
follow the steps he suggested.

Since Arcot junior's invention of the multiple calculus, many new
ramifications of old theories had been attained, and many developments
had become possible.

But the factor that made Arcot so amazingly successful in his line of
work was his ability to see practical uses for things, an ability that
is unfortunately lacking in so many great physicists. Had he collected
the royalties his inventions merited, he would have been a billionaire
twice or thrice over. Instead he had made contracts on the basis that
the laboratories he owned be kept in condition, and that he be paid a
salary that should be whatever he happened to need. Since he had sold
all his inventions to Transcontinental Airways, he had been able to
devote all his time to science, leaving them to manage his finances.
Perhaps it was the fact that he did sell these inventions to
Transcontinental that made these lines so successful; but at any rate,
President Arthur Morey was duly grateful, and when his son was able to
enter the laboratories he was as delighted as Arcot.

The two had become boon companions. They worked, played, lived, and
thought together.

Just now they were talking about the Pirate. This was the seventh day of
his discovery, and he had been growing steadily more menacing. It was
the great Transcontinental Airways that had suffered most repeatedly.
Sometimes it was the San Francisco Flyer that went on without a pilot,
sometimes the New York-St. Louis expresses that would come over the
field broadcasting the emergency signal. But always the people were
revived with little difficulty, and each time more of the stock of
"Piracy, Inc." was accumulated. The Air Guard seemed helpless. Time and
time again the Pirate slipped in undetected. Each time he convinced
them that it was an outside job, for the door was always sealed from the
outside.

"Dick, how do you suppose he gets away with the things he does right
under the eyes of those Air Guardsmen? He must have some system; he does
it every time."

"I have a vague idea," Arcot answered. "I was going to ask you today, if
your father would let us take passage on the next liner carrying any
money. I understand the insurance rates have been boosted so high that
they don't dare to send any cash by air any more. They've resorted to
the slow land routes. Is there any money shipment in sight?"

Morey shook his head. "No, but I have something that's just as good, if
not better, for our purpose. The other day several men came into Dad's
office, to charter a plane to San Francisco, and Dad naturally wondered
why they had been referred to the president of the company. It seems the
difficulty was that they wanted to hire the ship so they could be
robbed! A large group of medical men and cancer victims were going for
the 'treatment'. Each one of the twenty-five hundred going was to bring
along one hundred dollars. That meant a total of a quarter of a million
dollars, which is to be left on the table. They hoped the Pirate would
gas them and thus cure them! Dad couldn't officially do this, but told
them that if there were too many people for the San Francisco express,
two sections would be necessary. I believe they are going on that second
section. Only one hundred dollars! A low price for cancer cure!

"Another thing: Dad asked me to tell you that he'd appreciate your help
in stopping this ultra-modern pirate. If you go down to see him in the
morning, you'll doubtless be able to make the necessary arrangements."

"I'll do so gladly. I wonder, though, if you know more about this than I
do. Did they try that C-32L mask on an animal?"

"The Pirate was telling the truth. They tried it on a dog and he went to
sleep forever. But do you have any idea how that gas does all it does?"

Now Arcot shook his head. "I don't know what the gas is, but have a lead
on how it works. You may know that carbon monoxide will seep through a
solid plate of red-hot steel. That has been known for some three hundred
years now, and I have to hand it to this Pirate for making use of it.
Even in the war of 2075 they didn't find any practical application for
the principle. He has just found some gas that induces sleep in very low
concentrations, and at the same time is able to penetrate to an even
greater extent than carbon monoxide."

"I was wondering how he stores that stuff," Morey commented. "But I
suppose he makes it as fast as he uses it, by allowing two or more
constituents to react. It might well be simple enough to store them
separately, and the air-stream blowing past him would carry the gas
behind him, permitting him to lay a stream of it in front of the big
plane. Is that about it?"

"That was about what I had figured. One of the things I want to do when
I go with that Invalid Special tomorrow is to get some samples for
analysis."

"That's a pretty big order, isn't it, Dick? How are you going to handle
it, or even get it into your apparatus?"

"Easily enough as far as getting the sample goes. I have already had
some sample bottles made. I have one of them in the lab--excuse me a
moment." Arcot left the room, to return a few minutes later with a large
aluminum bottle, tightly closed. "This bottle has been pumped out to a
very good vacuum. I then swept it out with helium gas. Then it was
pumped out again. I hope to take this into some gas-filled region, where
the gas will be able to leak in, but the air won't. When it comes to
going out again, the gas will have to fight air pressure, and will
probably stay in."

"Hope it works. It would help if we knew what we were bucking."

       *       *       *       *       *

The next morning Arcot had a long conference with President Morey. At
the end of it, he left the office, ascended to the roof, and climbed
into his small helicopter. He rose to the local traffic level, and
waiting his chance, broke into the stream of planes bound for the great
airfields over in the Jersey district. A few minutes later he landed on
the roof of the Transcontinental Airways shops, entered them, and went
to the office of the Designing Engineer, John Fuller, an old schoolmate.
They had been able to help each other before, for Fuller had not paid as
much attention to theoretical physics as he might have, and though he
was probably one of the outstanding aeronautical designers, he often
consulted Arcot on the few theoretical details that he needed. Probably
it was Arcot who derived the greatest benefit from this association, for
the ability of the designer had many times brought his theoretical
successes to practical commercial production. Now, however, he was
consulting Fuller, because the plane he was to take that afternoon for
San Francisco was to be slightly changed for him.

He stayed in Fuller's office for the better part of an hour, then
returned to the roof and thence to his own roof, where Morey junior was
waiting for him.

"Hello, Dick! I heard from Dad that you were going this afternoon, and
came over here. I got your note and I have the things fixed up here. The
plane leaves at one, and it's ten-thirty now. Let's eat lunch and then
start."

It was half-past eleven when they reached the flying field. They went
directly to the private office which had been assigned to them aboard
the huge plane. It was right next to the mail-room, and through the wall
between the two a small hole had been cut. Directly beneath this hole
was a table, on which the two men now set up a small moving picture
camera they had brought with them.

"How many of the gas sample bottles did you bring, Bob?" asked Arcot.

"Jackson had only four ready, so I brought those. I think that will be
enough. Have we got that camera properly placed?"

"Everything's O.K., I believe. Nothing to do now but wait."

Time passed--then they heard a faint whir; the ventilator machinery had
started. This drew air in from outside, and pumped it up to the
necessary pressure for breathing in the ship, no matter what the
external pressure might be. There was a larger pump attached similarly
to each of the engines to supply it with the necessary oxygen. Any loss
in power by pumping the air in was made up by the lower back pressure on
the exhaust. Now the engines were starting--they could feel the
momentary vibration--vibration that would cease as they got under way.
They could visualize the airtight door being closed; the portable
elevator backing off, returning to the field house.

Arcot glanced at his watch. "One o'clock. The starting signal is due."

Morey sank back into a comfortable chair. "Well, now we have a nice long
wait till we get to San Francisco and back, Dick, but you'll have
something to talk about then!"

"I hope so, Bob, and I hope we can return on the midnight plane from San
Francisco, which will get us in at nine o'clock tomorrow morning, New
York time. I wish you'd go right to your father's office and ask him
over to our place for supper, and see if Fuller can come too. I think
we'll be able to use that molecular controller on this job; it's almost
finished, and with it we'll need a good designing engineer. Then our
little movie show will no doubt be of interest!"

There was a low rumble that quickly mounted to a staccato roar as the
great propellers began whirling and the engines took up the load. The
ground began to flash behind them; then suddenly, as flying speed was
reached, there was a slight start, the roaring bark of the engine took
on a deeper tone, the rocking stopped and the ground dropped away. Like
some mighty wild bird, the plane was in the air, a graceful, sentient
thing, wheeling in a great circle as it headed for San Francisco. Now
the plane climbed steadily in a long bank; up, up, up she went, and
gradually the terrific roar of the engine died to a low throbbing hum as
the low pressure of the air silenced the noise.

Below them the giant city contracted as the great ship rode higher. The
tiny private helicops were darting about below them like streams of nigh
invisible individuals, creeping black lines among the buildings of the
city. The towering buildings shone in the noon sun in riotous hues as
the colored tile facing reflected the brilliant sunlight with glowing
warmth of color.

It was a city of indescribable beauty now. It was one of the things that
made this trip worthwhile.

Now the shining city dropped behind them, and only the soft green of the
Jersey hills, and the deep purple-black of the sky above were visible.
The sun blazed high in the nigh-black heavens, and in the rarefied air,
there was so little diffusion that the corona was readily visible with
the aid of a smoked glass. Around the sun, long banners in space, the
Zodiacal light gleamed dimly. Here and there some of the brighter stars
winked in the dark sky.

Below them the landscape swung slowly by. Even to these men who had made
the trip dozens of times, the sight was fascinating, inspiring. It was a
spectacle which had never been visible before the development of these
super-planes. Whole flying observatories had been made that had taken
photographs at heights of fifteen miles, where the air was so rarefied
that the plane had to travel close to eight hundred miles an hour to
remain aloft.

Already ahead of them Arcot and Morey could see the great splotch of
color that was Chicago, the mightiest city of Earth. Situated as it was
in the heart of the North American continent, with great water and
ground landing facilities and broad plains about it, it made a perfect
airport. The sea no longer meant much, for it was now only a source of
power, recreation and food. Ships were no longer needed. Planes were
faster and more economical; hence seacoast cities had declined in
importance. With its already great start toward ascendancy, Chicago had
rapidly forged ahead, as the air lines developed with the great
super-planes. The European planes docked here, and it was the starting
point of the South American lines. But now, as they swung high above it,
the glistening walls of soft-colored tiles made it a great mass of
changing, flashing color beneath them. Now they could see a great air
liner, twice the size of their plane, taking off for Japan, its six
giant propellers visible only as flashing blurs as it climbed up toward
them. Then it was out of sight.

It was over the green plains of Nebraska that the Pirate usually worked,
so there the men became more and more alert, waiting for the first sign
of abnormal drowsiness. They sat quietly, not talking, listening
intently for some new note, but knowing all the while that any sound the
Pirate might make would be concealed by the whirring roar of the air
sweeping past the giant airfoils of the plane.

Suddenly Arcot realized he was unbearably sleepy. He glanced drowsily
toward Morey who was already lying down. He found it a tremendous effort
of the will to make himself reach up and close the switch that started
the little camera whirring almost noiselessly. It seemed he never pulled
his arm back--he just--lay there--and--

A white uniformed man was bending over him as he opened his eyes. To one
side of him he saw Morey smiling down at him.

"You're a fine guard, Arcot. I thought you were going to stay awake and
watch them!"

"Oh, no, I left a much more efficient watchman! _It_ didn't go to
sleep--I'm willing to bet!"

"No, it may not have gone to sleep, but the doctor here tells me it has
gone somewhere else. It wasn't found in our room when we woke up. I
think the Pirate found it and confiscated it. All our luggage, including
the gas sample bottles, is gone."

"That's all right. I arranged for that. The ship was brought down by an
emergency pilot and he had instructions from father. He took care of the
luggage so that no member of the pirate's gang could steal it. There
might have been some of them in the ground crew. They'll be turned over
to us as soon as we see the emergency man. I don't have to lie here any
longer, do I, doctor?"

"No, Dr. Arcot, you're all right now. I would suggest that for the next
hour or so you take it easy to let your heart get used to beating again.
It stopped for some two hours, you know. You'll be all right, however."




II


Five men were seated about the Morey library, discussing the results of
the last raid, in particular as related to Arcot and Morey. Fuller, and
President Morey, as well as Dr. Arcot, senior, and the two young men
themselves, were there. They had consistently refused to tell what their
trip had revealed, saying that pictures would speak for them. Now they
turned their attention to a motion picture projector and screen that
Arcot junior had just set up. At his direction the room was darkened;
and he started the projector. At once they were looking at the three
dimensional image of the mail-room aboard the air liner.

Arcot commented: "I have cut out a lot of useless film, and confined the
picture to essentials. We will now watch the pirate at work."

Even as he spoke they saw the door of the mail-room open a bit, and
then, to their intense surprise, it remained open for a few seconds,
then closed. It went through all the motions of opening to admit
someone, yet no one entered!

"Your demonstration doesn't seem to show much yet, son. In fact, it
shows much less than I had expected," said the senior Arcot. "But that
door seemed to open easily. I thought they locked them!"

"They did, but the pirate just burned holes in them, so to save property
they leave 'em unlocked."

Now the scene seemed to swing a bit as the plane hit an unusually bad
air bump, and through the window they caught a glimpse of one of the
circling Air Guardsmen. Then suddenly there appeared in the air within
the room a point of flame. It hung in the air above the safe for an
instant, described a strangely complicated set of curves; then, as it
hung for an instant in mid-air, it became a great flare. In an instant
this condensed to a point of intensely brilliant crimson fire. This
described a complex series of curves and touched the top of the safe. In
an inconceivably short time, the eight-inch thickness of tungsto-iridium
alloy flared incandescently and began to flow sluggishly. A large circle
of the red flame sprang out to surround the point of brilliance, and
this blew the molten metal to one side, in a cascade of sparks.

In moments, the torch had cut a large disc of metal nearly free;
seemingly on the verge of dropping into the safe. Now the flame left the
safe, again retracting itself in that uncanny manner, no force seeming
either to supply it with fuel or to support it thus, though it burned
steadily, and worked rapidly and efficiently. Now, in mid-air, it hung
for a second.

"I'm going to work the projector for a few moments by hand so that you
may see this next bit of film." Arcot moved a small switch and the
machine blinked, giving a strange appearance to the seemingly solid
images that were thrown on the screen.

The pictures seemed to show the flame slowly descending till it again
touched the metal. The tungsto-iridium glowed briefly; then, as suddenly
as the extinguishing of a light, the safe was gone! It had disappeared
into thin air! Only the incandescence of the metal and the flame itself
were visible.

"It seems the pirate has solved the secret of invisibility. No wonder
the Air Guardsmen couldn't find him!" exclaimed Arcot, senior.

The projector had been stopped exactly on the first frame, showing the
invisibility of the safe. Then Arcot backed it up.

"True, Dad," he said, "but pay special attention to this next frame."

Again there appeared a picture of the room, the window beyond, the mail
clerk asleep at his desk, everything as before, except that where the
safe had been, _there was a shadowy, half visible safe_, the metal
glowing brightly. Beside it there was visible a shadowy man, holding
the safe with a shadowy bar of some sort. And through both of them the
frame of the window was perfectly visible, and, ironically, an Air
Guardsman plane.

"It seems that for an instant his invisibility failed here. Probably it
was the contact with the safe that caused it. What do you think, Dad?"
asked Arcot, junior.

"It does seem reasonable. I can't see off-hand how his invisibility is
even theoretically possible. Have you any ideas?"

"Well, Dad, I have, but I want to wait till tomorrow night to
demonstrate them. Let's adjourn this meeting, if you can all come
tomorrow."

       *       *       *       *       *

The next evening, however, it seemed that it was Arcot himself who could
not be there. He asked Morey, junior, to tell them he would be there
later, when he had finished in the lab.

Dinner was over now, and the men were waiting rather impatiently for
Arcot to come. They heard some noise in the corridor, and looked up, but
no one entered.

"Morey," asked Fuller, "what did you learn about that gas the pirate was
using? I remember Arcot said he would have some samples to analyze."

"As to the gas, Dick found out but little more than we had already
known. It is a typical organic compound, one of the metal radical type,
and contains one atom of thorium. This is a bit radioactive, as you
know, and Dick thinks that this may account in part for its ability to
suspend animation. However, since it was impossible to determine the
molecular weight, he could not say what the gas was, save that the
empirical formula was C_{62}TH H_{39}O_{27}N_{5}. It broke down at a
temperature of only 89° centigrade. The gases left consisted largely of
methane, nitrogen, and methyl ether. Dick is still in the dark as to
what the gas is." He paused, then exclaimed: "Look over there!"

The men turned with one accord toward the opposite end of the room,
looked, and seeing nothing particularly unusual, glanced back rather
puzzled. What they then saw, or better, failed to see, puzzled them
still more. Morey had disappeared!

"Why--why where--ohhh! Quick work, Dick!" The senior Arcot began
laughing heartily, and as his astonished and curious companions looked
toward him, he stopped and called out, "Come on, Dick! We want to see
you now. And tell us how it's done! I rather think Mr. Morey here--I
mean the visible one--is still a bit puzzled."

There was a short laugh from the air--certainly there could be nothing
else there--then a low but distinct click, and both Morey and Arcot were
miraculously present, coming instantaneously from nowhere, if one's
senses could be relied on. On Arcot's back there was strapped a large
and rather hastily wired mechanism--one long wire extending from it out
into the laboratory. He was carrying a second piece of apparatus,
similarly wired. Morey was touching a short metal bar that Arcot held
extended in his hand, using a table knife as a connector, lest they get
radio frequency burns on making contact.

"I've been busy getting the last connection of this portable apparatus
rigged up. I have the thing in working order, as you see--or rather,
didn't see. This other outfit here is the thing that is more important
to us. It's a bit heavy, so if you'll clear a space, I'll set it down.
Look out for my power supply there--that wire is carrying a rather
dangerously high E.M.F. I had to connect with the lab power supply to do
this, and I had no time to rig up a little mechanism like the one the
pirate must have.

"I have duplicated his experiment. He has simply made use of a principle
known for some time, but as there was no need for it, it hasn't been
used. It was found back in the early days of radio, as early as the
first quarter of the twentieth century, that very short wavelengths
effected peculiar changes in metals. It was shown that the plates of
tubes working on very short waves became nearly transparent. The waves
were so short, however, that they were economically useless. They would
not travel in usable paths, so they were never developed. Furthermore,
existing apparatus could not be made to handle them. In the last war
they tried to apply the idea for making airplanes invisible, but they
could not get their tubes to handle the power needed, so they had to
drop it. However, with the tube I recently got out on the market, it is
possible to get down there. Our friend the pirate has developed this
thing to a point were he could use it. You can see that invisibility,
while interesting, and a good thing for a stage and television
entertainment, is not very much of a commercial need. No one wants to be
invisible in any honest occupation. Invisibility is a tremendous weapon
in war, so the pirate just started a little private war, the only way he
could make any money on his invention. His gas, too, made the thing
attractive. The two together made a perfect combination for criminal
operations.

"The whole thing looks to me to be the work of a slightly unbalanced
mind. He is not violently insane; probably just has this one particular
obsession. His scientific bump certainly shows no sign of weakness. He
might even be some new type of kleptomaniac. He steals things, and he
has already stolen far more than any man could ever have any need of,
and he leaves in its place a 'stock' certificate in his own company. He
is not violent, for hasn't he carefully warned the men not to use the
C-32L mask? You'll remember his careful instructions as to how to revive
the people!

"He has developed this machine for invisibility, and naturally he can
fly in and out of the air guard, without their knowing he's there,
provided their microphonic detectors don't locate him. I believe he uses
some form of glider. He can't use an internal combustion engine, for the
explosions in the cylinders would be as visible as though the cylinders
were made of clear quartz. He cannot have an electric motor, for the
storage cells would weigh too much. Furthermore, if he were using any
sort of prop, or a jet engine, the noise would give him away. If he used
a glider, the noise of the big plane so near would be more than enough
to kill the slight sounds. The glider could hang above the ship, then
dive down upon it as it passed beneath. He has a very simple system of
anchoring the thing, as I discovered to my sorrow. It's a powerful
electro-magnet which he turns on when he lands. The landing deck of the
big plane was right above our office aboard, and I found my watch was
doing all sorts of antics today. It lost an hour this morning, and this
afternoon it gained two. I found it was very highly magnetized--I could
pick up needles with the balance wheel. I demagnetized it; now it runs
all right.

"But to get back, he anchors his ship, then, leaving it invisible, he
goes to the air lock, and enters. He wears a high altitude suit, and on
his back he has a portable invisibility set and the fuel for his torch.
The gas has already put everyone to sleep, so he goes into the ship,
still invisible, and melts open the safe.

"His power supply for the invisibility machine seems to be somewhat of a
problem, but I think I would use a cylinder of liquid air, and have a
small air turbine to run a high voltage generator. He probably uses the
same system on a larger scale to run his big machine on the ship. He
can't use an engine for that either.

"That torch of his is interesting, too. We have had atomic hydrogen
welding for some time, and atomic hydrogen releases some 100,000
calories per mole of molecular hydrogen; two grains of gas give one
hundred thousand calories. Oxygen has not been prepared in any
commercial quantity in the atomic state. From watching that man's torch,
from the color of the flame and other indications, I gather that he uses
a flame of atomic oxygen-atomic hydrogen for melting, and surrounds it
with a preheating jacket of atomic hydrogen. The center flame probably
develops a temperature of some 4000° centigrade, and will naturally make
that tungsten alloy run like water.

"As to the machine here--it is, as I said, a machine which impresses
very high frequencies on the body it is connected with. This puts the
molecules in vibration at a frequency approaching that of light, and
when the light impinges upon it, it can pass through readily. You know
that metals transmit light for short distances, but in order that the
light pass, the molecules of metal must be set in harmonic vibration at
a rate approaching the frequency of light. If we can impress such a
vibration on a piece of matter, it will then transmit light very freely.
If we impress this vibration on the matter, say the body, electrically,
we get the same effect and the body becomes perfectly transparent. Now,
since it is the vibration of the molecules that makes the light pass
through the material, it must be stopped if we wish to see the machine.
Obviously it is much easier to detect me here among solid surroundings,
than in the plane high in the sky. What chance has one to detect a
machine that is perfectly transparent when there is nothing but
perfectly transparent air around it? It is a curious property of this
vibrational system of invisibility that the index of refraction is made
very low. It is not the same as that of air, but the difference is so
slight that it is practically within the limits of observation error; so
small is the difference that there is no 'rainbow' effect. The
difference of temperature of the air would give equal effect.

"Now, since this vibration is induced by radio impulse, is it not
possible to impress another, opposing radio impulse, that will overcome
this tendency and bring the invisible object into the field of the
visible once more? It is; and this machine on the table is designed to
do exactly that. It is practically a beam radio set, projecting a beam
of a wavelength that alone would tend to produce invisibility. But in
this case it will make me visible. I'm going to stand right here, and
Bob can operate that set."

Arcot strode to the middle of the room, and then Morey turned the
reflector of the beam set on him. There was a low snap as Arcot turned
on his set, then he was gone, as suddenly as the coming of darkness when
a lamp is extinguished. He was there one moment, then they were staring
at the chair behind him, knowing that the man was standing between them
and it and knowing that they were looking through his body. It gave them
a strange feeling, an uncomfortable tingling along the spine. Then the
voice--it seemed to come from the air, or some disembodied ghost as the
invisible man called to Morey.

"All right, Bob, turn her on slowly."

There was another snap as the switch of the disrupter beam was turned
on. At once there was a noticeable fogginess in the air where Arcot had
been. As more and more power was turned into the machine, they saw the
man materialize out of thin air. First he was a mere shadowy outline
that was never fully above the level of conscious vision. Then slowly
the outlines of the objects behind became dimmer and dimmer, as the body
of the man was slowly darkened, till at last there was only a wavering
aura about him. With a snap Morey shut off his machine and Arcot was
gone again. A second snap and he was solid before them. He had shut off
his apparatus too.

"You can see now how we intend to locate our invisible pirate. Of course
we will depend on directional radio disturbance locating devices to
determine the direction for the invisibility disrupter ray. But you are
probably marvelling at the greatness of the genius who can design and
construct this apparatus all in one day. I will explain the miracle. I
have been working on short wave phenomena for some time. In fact, I had
actually made an invisibility machine, as Morey will testify, but I
realized that it had no commercial benefits, so I didn't experiment with
it beyond the laboratory stunt stage. I published some of the theory in
the Journal of the International Physical Society--and I wouldn't be
surprised to learn that the pirate based his discovery on my report.

"I am still working on a somewhat different piece of apparatus that I
believe we will find very relevant to this business. I'll ask you to
adjourn after tonight's meeting for another twenty-four hours till I can
finish the apparatus I am working on. It is very important that you be
here, Fuller. I am going to need you in the work to follow. It will be
another problem of design if this works out, as I hope it will."

"I'll certainly make every effort to be here, Arcot," Fuller assured
him.

"I can promise you a tough problem as well as an interesting one." Arcot
smiled. "If the thing works, as I expect it to, you'll have a job that
will certainly be a feather for your cap. Also it will be a change."

"Well, with that inducement, I'll certainly be here. But I think that
pirate could give us some hints on design. How does he get his glider
ten miles up? They've done some high-altitude gliding already. The
distance record took someone across the Atlantic in 2009, didn't it? But
it seems that ten miles straight up is a bit too steep for a glider.
There are no vertical air currents at that height."

"I meant to say that his machine is not a true glider, but a
semi-glider. He probably goes up ten miles or more with the aid of a
small engine, one so small it probably takes him half a day to get
there. And it would be easy for a plane to pass through the lower
traffic lanes, then, being invisible, mount high and wait for the air
liner. He can't use a very large engine, for it would drag him down, but
one of the new hundred horsepower jobs would weigh only about fifty
pounds. I think we can draw a pretty good picture of his plane from
scientific logic. It probably has a tremendous wingspread and a very
high angle of incidence to make it possible to glide at that height, and
the engine and prop will be almost laughably small."

       *       *       *       *       *

The next evening the men got together for dinner, and there was
considerable speculation as to the nature of the discovery that Arcot
was going to announce, for even his father had no knowledge of what it
was. The two men worked in separate laboratories, except when either had
a particularly difficult problem that might be solved by the other. All
knew that the new development lay in the field of short wave research,
but they could not find out in what way it concerned the problem in
hand.

At last the meal was over, and Arcot was ready to demonstrate.

"Dad, I believe that you have been trying to develop a successful solar
engine. One that could be placed in the wings of a plane to generate
power from the light falling on that surface. In all solar engines what
is the greatest problem to be solved?"

"Well, the more I investigate the thing, the more I wonder which is the
greatest. There are a surprising number of annoying problems to be met.
I should say, though, that the one big trouble with all solar engines,
eliminating the obvious restriction that they decidedly aren't
dependable for night work, is the difficulty of getting an area to
absorb the energy. If I could get enough area, I could use a very low
efficiency and still have cheap power, for the power is absolutely free.
The area problem is the greatest difficulty, no doubt."

"Well," Arcot junior said quietly, "I think you have a fairly good area
to use, if you can only harness the energy it absorbs. I have really
developed a very efficient solar engine. The engine itself requires no
absorbing area, as I want to use it; it takes advantage of the fact that
the Earth is absorbing quintillions of horsepower. I have merely tapped
the power that the Earth has already absorbed for me. Come here."

He led the way down the corridor to his laboratory, and switched on the
lights. On the main laboratory bench was set up a complicated apparatus
of many tubes and heavy bus bar connectors. From the final tube two thin
wires ran to a long tubular coil. To the left of this coil was a large
relay switch, and a rheostat control.

"Turn on the relay, Dad, then slowly rotate the controller to the left.
And remember that it is rather powerful; I know this doesn't look like a
solar engine, and nine o'clock at night seems a peculiar hour to
demonstrate such a thing, but I'll guarantee results--probably more than
you expect."

Dr. Arcot stepped up to the controls and closed the switch. The lights
dimmed a bit, but immediately brightened again, and from the other end
of the room came a low, steady hum as the big transformer took up the
load.

"Well, from the sound of that ten K.W. transformer there, if this engine
is very efficient we ought to get a terrific amount of power out of it."
Dr. Arcot was smiling amusedly at his son. "I can't very well control
this except by standing directly in front of it, but I suppose you know
what you're doing."

"Oh, this is a laboratory model, and I haven't gotten the thing into
shape really. Look at the conductors that lead to the coil; they
certainly aren't carrying ten K.W."

Dr. Arcot slowly rotated the rheostat. There was a faint hum from the
coil; then it was gone. There seemed to be no other result. He rotated
it a bit more; a slight draught sprang up within the room. He waited,
but when nothing more startling occurred, he gave the rheostat a sharp
turn. This time there was absolutely no doubt as to the result. There
was a roar like a fifty-foot wind tunnel, and a mighty blast of cold air
swept out of that coil like a six-inch model of a Kansas cyclone. Every
loose piece of paper in the laboratory came suddenly alive and whirled
madly before the blast of air that had suddenly leaped out. Dr. Arcot
was forced back as by a giant hand; in his backward motion his hand was
lifted from the relay switch, and with a thud the circuit opened. In an
instant the roar of sound was cut off, and only a soft whisper of air
told of the furious blast that had been there a moment before.

The astonished physicist came forward and looked at the device a moment
in silence, while each of the other men watched him. Finally he turned
to his son, who was smiling at him with a twinkle in his eye.

"Dick, I think you have 'loaded the dice' in a way that is even more
lucrative than any other method ever invented! If the principle of this
machine is what I think it is, you have certainly solved the secret of a
sufficiently absorbing area for a solar engine."

"Well," remarked the elderly Morey, shivering a bit in the chill air of
the room, "loaded dice have long been noted for their ability to make
money, but I don't see how that explains that working model of an Arctic
tornado. _Burr_ it's still too cold in here. I think he'll need
considerable area for heat absorption from the sun, for that engine
certainly does cool things down! What's the secret?"

"The principle is easy enough, but I had considerable difficulty with
the application. I think it is going to be rather important though--"

"Rather important," broke in the inventor's father, with a rare display
of excitement. "It will be considerably more than that. It's the biggest
thing since the electric dynamo! It puts airplanes in the junk heap! It
means a new era in power generation. Why, we'll never have to worry
about power! It will make interplanetary travel not only possible, but
commercially economical."

Arcot junior grinned broadly. "Dad seems to think the machine has
possibilities! Seriously, I believe it will antiquate all types of
airplanes, prop or jet. It's a direct utilization of the energy that the
sun is kindly supplying. For a good many years now men have been trying
to find out how to control the energy of atoms for air travel, or to
release the energy of the constitution of matter.

"But why do it at all? The sun is doing it already, and on a scale so
gargantuan that we could never hope nor desire to approach it. Three
million tons of matter go into that colossal furnace every second of
time, and out of that comes two and a half decillion ergs of energy.
With a total of two and a half million billion billion billions of ergs
to draw on, man will have nothing to worry about for a good many years
to come! That represents a flood of power vaster than man could
comprehend. Why try to release any more energy? We have more than we can
use; we may as well tap that vast ocean of power.

"There is one thing that prevents us getting it out, the law of
probability. That's why Dad mentioned loaded dice, for dice, as you
know, are the classical example of probability when they aren't loaded.
Once they are loaded, the law still holds, but the conditions are now so
changed that it will make the problem quite different."

Arcot paused, frowning, then resumed half apologetically, "Excuse the
lecture--but I don't know how else to get the thought across. You are
familiar with the conditions in a liter of helium gas in a container--a
tremendous number of molecules, each dashing along at several miles a
second, and an equal number dashing in the opposite direction at an
equal speed. They are so thickly packed in there, that none of them can
go very far before it runs into another molecule and bounces off in a
new direction. How good is the chance that all the molecules should
happen to move in the same direction at the same time? One of the old
physicists of Einstein's time, a man named Eddington, expressed it very
well:

    'If an army of monkeys were playing on typewriters they
    might write all the books in the British Museum. The
    chance of their doing so is decidedly more favorable
    than the chance that all the molecules in a liter of
    gas should move in the same direction at the same
    time.'

The very improbability of this chance is the thing that is making our
problem appear impossible.

"But similarly it would be improbable--impossible according to the law
of chance--to throw a string of aces indefinitely. It is
impossible--unless some other force influences the happening. If the
dice have bits of iridium stuck under the six spots, they will throw
aces. Chance makes it impossible to have all the molecules of gas move
in the same direction at the same time--unless we stack the chances. If
we can find some way to influence them, they may do so.

"What would happen to a metal bar if all the molecules in it decided to
move in the same direction at the same time? Their heat motion is
normally carrying them about at a rate of several miles a second, and if
now we have them all go in one way, the entire bar must move in that
direction, and it will start off at a velocity as great as the velocity
of the individual molecules. But now, if we attach the bar to a heavy
car, it will try to start off, but will be forced to drag the car with
it, and so will not be able to have its molecules moving at the same
rate. They will be slowed down in starting the mass of the car. But
slowly moving molecules have a definite physical significance. Molecules
move because of temperature, and lack of motion means lack of heat.
These molecules that have been slowed down are then cold; they will
absorb heat from the air about them, and since the molecule of hydrogen
gas at room temperature is moving at about seven miles a second, when
the molecules of the confined gas in our car, or the molecules of the
metal bar are slowed down to but a few hundred miles an hour, their
temperature drops to some hundreds of degrees below zero, and they
absorb energy very rapidly, for the greater the difference in
temperature, the greater the rate of heat absorption.

"I believe we will be able to accelerate the car rapidly to a speed of
several miles a second at very high altitudes, and as we will be able to
use a perfectly enclosed streamlined car, we should get tremendous
speeds. We'll need no wings, of course, for with a small unit pointed
vertically, we'll be able to support the car in the air. It will make
possible a machine that will be able to fly in reverse and so come to a
quick stop. It will steer us or it will supply us with electrical power,
for we merely have to put a series of small metal bars about the
circumference of the generator, and get a tremendously powerful engine.

"For our present need, it means a tremendously powerful engine--and one
that we can make invisible.

"I believe you can guess the source of that breeze we had there? It
would make a wonderful air-conditioning unit."

"Dick Arcot," began Morey, his voice tight with suppressed excitement,
"I would like to be able to use this invention. I know enough of the
economics of the thing, if not its science, to know that the apparatus
before us is absolutely invaluable. I couldn't afford to buy the rights
on it, but I want to use it if you'll let me. It means a new era in
transcontinental air travel!"

He turned sharply to Fuller. "Fuller, I want you to help Arcot with the
ship to chase the Pirate. You'll get the contract to design the new
airliners. Hang the cost. It'll run into billions--but there will be no
more fuel bills, no oil bills, and the cost of operation will be
negligible. Nothing but the Arcot short wave tubes to buy--and each one
good for twenty-five thousand hours service!"

"You'll get the rights on this if you want them, of course," said Arcot
quietly. "You're maintaining these laboratories for me, and your son
helped me work it out. But if Fuller can move over here tomorrow, it
will help things a lot. Also I'd like to have some of your best
mechanics to make the necessary machines, and to start the power units."

"It's done," Morey snapped.




III


Early the next morning Fuller moved his equipment over to the laboratory
and set up his table for work. There Arcot and Morey joined him, and the
designing of the new machine was started.

"First, let's get some idea of the most advisable shape," Fuller began
methodically. "We'll want it streamlined, of course; roughly speaking, a
cylinder modified to fit the special uses to which it will be put. But
you probably have a general plan in mind, Arcot. Suppose you sketch it
for us."

The big physicist frowned thoughtfully. "Well, we don't know much about
this yet, so we'll have to work it out. You'll have plenty of fun
figuring out strains in this machine, so let's be safe and use a factor
of safety of five. Let's see what we'll need.

"In the first place, our machine must be proof against the Pirate's gas,
for we won't be riding a beam with instruments to guide us safely, if we
pass out. I've thought that over, and I think that the best system is
just what we used in the sample bottles--a vacuum. His gas is stopped by
nothing, so to speak, but there is no substance that will stop it! It
will no doubt penetrate the outer shell, but on reaching the vacuum, it
will tend to stay there, between the inner and outer walls. Here it will
collect, since it will be fighting air pressure in going either in or
out. The pressure inside will force it back, and the pressure outside
will force it in. If we did not pump it out, it would soon build up
pressure enough to penetrate the interior wall. Now, since the stuff can
leak through any material, what kind of a pump shall we use? It won't be
pushed by a piston, for it will leak through either the cylinder walls
or the piston. A centrifugal pump would be equally ineffective. A
mercury vapor pump will take it out, of course, and keep a high vacuum,
but we'd never make any progress.

"Our new machine gives us the answer. With it we can just have a number
of openings in the wall of the outer shell, and set in them one of these
molecular motion directors, and direct the molecules into the outside
air. They can't come in through it, and they will go out!"

"But," Morey objected, "the vacuum that keeps out the gas will also keep
out heat, as well! Since our generator is to run on heat energy, it will
be rather chilly inside if we don't remedy that. Of course, our power
units could be placed outside, where the blast of air will warm them,
but we really won't have a very good streamline effect if we hang a big
electric generator outside."

"I've thought of that too," Arcot answered. "The solution is obvious--if
we can't bring the generator to the air, we must bring the air to it."
He began sketching rapidly on the pad before him, "We'll have all the
power equipment in this room here in the back, and the control room up
in front, here. The relays for controlling will be back here, so we can
control electrically the operation of the power equipment from our warm,
gas-tight room. If it gets too warm in there, we can cool it by using a
little of the heat to help accelerate the ship. If it is too cold, we
can turn on an electric heater run by the generator. The air for the
generator can come in through a small sort of scoop on top, and leave
through a small opening in the rear. The vacuum at the tail will assure
us a very rapid circulation, even if the centrifugal pump action of the
enclosed generator isn't enough."

His thoughts began moving more rapidly than his words. "We'll want the
generator greatly over power to run tests over a greater range. Won't
need more than one hundred kilowatts altogether, but should install
about a thousand--A.C., of course. Batteries in the keel for starting
the generator.... Self-supporting when it's rolling....

"But let's set down some actual figures on this."

For the rest of the day the three men were working on the general plan
of the new ship, calculating the strengths needed, supplementing
mathematics with actual experiments with the machines on hand. The
calculating machines were busy continuously, for there were few rules
that experience could give them. They were developing something entirely
new, and though they were a designing staff of three of the foremost
mathematicians in the world, it was a problem that tested their
ingenuity to the utmost.

By the evening of the first day, however, they had been able to give the
finished designs for the power units to the mechanics who were to make
them. The order for the storage battery and the standard electrical
equipment had been placed at once. By the time they had completed the
drawings for the mail casting, the materials were already being
assembled in a little private camp that Morey owned, up in the hills of
Vermont. The giant freight helicopters could land readily in the wide
field that had been cleared on the small plateau, in the center of which
nestled a little blue lake and a winding trout brook.

The mechanics and electrical engineers had been sent up there
already--officially on vacation. The entire program could be carried out
without attracting the least attention, for such orders from the great
Transcontinental lines were so frequent that no importance was attached
to them.

Four days after the final plans had been completed the last of the
supplies were being assembled in the portable metal shed that was to
house the completed machine. The shining tungsto-steel alloy frame
members were rapidly being welded in place by cathode ray welding
torches in the hands of skilled artisans.

Already at the other end of the shop the generator had been arranged for
use with the molecular motion power units. The many power units to drive
and support the ship were finished and awaiting installation as the crew
quit work on the fourth evening. They would be installed on the frame in
the morning, and the generator would be hoisted into place with the
small portable crane. The storage batteries were connected, and in place
in the hull. The great fused quartz windows rested in their cases along
one wall, awaiting the complete application of the steel alloy plates.
They were to be over an inch thick, an unnecessary thickness, perhaps,
but they had no need to economize weight, as witnessed by their choice
of steel instead of light metal alloys throughout the construction.

The three men had arrived late that afternoon in a small helicopter, and
had gone directly to the shops to see what progress had been made. They
had been forced to remain in New York to superintend the shipment of the
necessary supplies to the camp site, and since no trouble was
anticipated in the making of the steel framework, they had not felt it
necessary to come. But now they would be needed to superintend the more
delicate work.

"She's shaping up nicely, isn't she?" Arcot gazed at the rapidly
rounding frame with a critical eye. Unhindered as they were by the
traditional shapes, by wings or other protuberances, they had been able
to design a machine of striking beauty. The ship was to retain its
natural metallic sheen, the only protection being a coat of "passivity
paint"--a liquid chemical that could be brushed or sprayed on iron,
chromium, nickel or cobalt alloys, rendering them passive to practically
all chemical agents. The new "paint" left the iron or steel as
brilliantly glossy as ever, but overcast with a beautiful iridescence,
and immune to the most powerful reagents.

The three men walked around the rapidly growing hull, and looked with
excited interest at the heavy welded joints and the great beams. The
ship seemed capable of withstanding a fall of several hundred feet with
little damage. The location of the power units was plainly visible and
easily recognized, for at each point there came together four or five
great beams, welded into one great mass of tough metal, and in it there
were set heavy tungsten bolts that would hold the units in place.

They inspected each joint minutely for signs of flaws, using a small
portable X-ray fluoroscope to see the interior of the metal. Each joint
seemed perfect. They retired, satisfied that everything was ready for
the work of the next day.

The morning began early with a long swim in the lake, and a hearty
breakfast of country cured ham and eggs. Then the work on the great
framework was continued, and that day saw the power units bolted in
place, removable if change was thought advisable. Each power unit was
equipped with long streamlined copper fins lying close to the rounded
hull, that they might absorb heat more rapidly.

Day by day the structure drew nearer completion, and, with the large
crew of highly skilled workers, the craft was practically complete
within a week. Only the instruments remained to be installed. Then at
last even these had been put in place, and with the aid of Fuller, Morey
junior, and his own father, Arcot had connected their many complicated
circuits.

"Son," remarked Arcot senior, looking critically at the great
switchboard, with its maze of connections, its many rheostats and
controls, and its heavy bus bar connectors behind it, "no one man can
keep an eye on all those instruments. I certainly hope you have a
good-sized crew to operate your controls! We've spent two days getting
all those circuits together, and I'll admit that some of them still have
me beat. I don't see how you intend to watch all those instruments, and
at the same time have any idea what's going on outside."

"Oh," laughed Arcot junior, "these aren't intended for constant
watching. They're merely helps in a lot of tests I want to make. I want
to use this as a flying laboratory so I can determine the necessary
powers and the lowest factor of safety to use in building other
machines. The machine is very nearly completed now. All we need is the
seats--they are to be special air-inflated gyroscopically controlled
seats, to make it impossible for a sudden twist of the ship to put the
strain in the wrong direction. Of course the main gyroscopes will
balance the ship laterally, horizontally, and vertically, but each chair
will have a separate gyroscopic mounting for safety."

"When do you expect to start after the Pirate?" Fuller asked.

"I plan to practice the manipulation of the machine for at least four
days," Arcot replied, "before I try to chase the Pirate. I'd ordinarily
recommend the greatest haste, but the man has stolen close to ten
million already, and he's still at it. That would not be done by anyone
in his right mind. I suppose you've heard, the War Department considers
his new gas so important that they've obtained a pardon for him on
condition they be permitted to have the secret of it. They demand the
return of the money, and I have no doubt he has it. I am firmly
convinced that he is a kleptomaniac. I doubt greatly if he will stop
taking money before he is caught. Therefore it will be safe to wait
until we can be sure of our ability to operate the machine smoothly. Any
other course would be suicidal. Also, I am having some of those
tool-makers make up a special type of molecular motion machine for use
as a machine gun. The bullets are steel, about three inches long, and as
thick as my thumb. They will be perfectly streamlined, except for a
little stabilizer at the tail, to guide 'em. They won't spin as a rifle
bullet does, and so there will be no gyroscopic effect to hold them nose
on, but the streamlining and the stabilizer will keep them on their
course. I expect them to be able to zip right through many inches of
armour plate, since they will have a velocity of over four miles a
second.

"They'll be fed in at the rate of about two hundred a minute--faster if
I wish, and started by a small spring. They will instantly come into the
field of a powerful molecular motion director, and will be shot out
with terrific speed. It will be the first rifle ever made that could
shoot bullets absolutely parallel to the ground.

"But that is all we can do today. The guns will be mounted outside, and
controlled electrically, and the charts will be installed tomorrow. By
the day after tomorrow at eight A.M. I plan to take off!"

The work the next day was rushed to completion far earlier than Arcot
had dared to hope. All the men had been kept isolated at the farm, lest
they accidentally spread the news of the new machine. It was with
excited interest that they helped the machine to completion. The guns
had not been mounted as yet, but that could wait. Mid-afternoon found
the machine resting in the great construction shed, completely equipped
and ready to fly!

"Dick," said Morey as he strode up to him after testing the last of the
gyroscopic seats, "she's ready! I certainly want to get her going--it's
only three-thirty, and we can go around to the sunlight part of the
world when it gets dark at the speeds we can travel. Let's test her
now!"

"I'm just as anxious to start as you are, Bob. I've sent for a U.S. Air
Inspector. As soon as he comes we can start. I'll have to put an 'X'
license indication on her now. He'll go with us to test it--I hope.
There will be room for three other people aboard, and I think you and
Dad and I will be the logical passengers."

He pointed excitedly. "Look, there's a government helicopter coming.
Tell the men to get the blocks from under her and tow her out. Two power
trucks should do it. Get her at least ten feet beyond the end of the
hangar. We'll start straight up, and climb to at least a five mile
height, where we can make mistakes safely. While you're tending to that,
I'll see if I can induce the Air Inspector to take a trip with us."

Half an hour later the machine had been rolled entirely out of the shed,
on the new concrete runway.

The great craft was a thing of beauty shimmering in the bright sunlight
The four men who were to ride in it on its maiden voyage stood off to
one side gazing at the great gleaming metal hull. The long sweeping
lines of the sides told a story of perfect streamlining, and implied
high speed, even at rest. The bright, slightly iridescent steel hull
shone in silvery contrast to the gleaming copper of the power units'
heat-absorption fins. The great clear windows in the nose and the low,
streamlined air intake for the generator seemed only to accentuate the
graceful lines of the machine.

"Lord, she's a beauty, isn't she, Dick!" exclaimed Morey, a broad smile
of pleasure on his face.

"Well, she did shape up nicely on paper, too, didn't she. Oh, Fuller,
congratulations on your masterpiece. It's even better looking than we
thought, now the copper has added color to it. Doesn't she look fast? I
wish we didn't need physicists so badly on this trip, so you could go on
the first ride with us."

"Oh, that's all right, Dick, I know the number of instruments in there,
and I realize they will mean a lot of work this trip. I wish you all
luck. The honor of having designed the first ship like that, the first
heavier-than-air ship that ever flew without wings, jets, or props--that
is something to remember. And I think it's one of the most beautiful
that ever flew, too."

"Well, Dick," said his father quietly, "let's get under way. It should
fly--but we don't really know that it will!"

The four men entered the ship and strapped themselves in the gyroscopic
seats. One by one they reported ready.

"Captain Mason," Arcot explained to the Air Inspector, "these seats may
seem to be a bit more active than one generally expects a seat to be,
but in this experimental machine, I have provided all the safety devices
I could think of. The ship itself won't fall, of that I am sure, but the
power is so great it might well prove fatal to us if we are not in a
position to resist the forces. You know all too well the effect of sharp
turns at high speed and the results of the centrifugal force. This
machine can develop such tremendous power that I have to make provision
for it.

"You notice that my controls and the instruments are mounted on the arm
of the chair really; that permits me to maintain complete control of the
ship at all times, and still permits my chair to remain perpendicular to
the forces. The gyroscopes in the base here cause the entire chair to
remain stable if the ship rolls, but the chair can continue to revolve
about this bearing here so that we will not be forced out of our seats.
I'm confident that you'll find the machine safe enough for a license.
Shall we start?"

"All right, Dr. Arcot," replied the Air Inspector. "If you and your
father are willing to try it, I am."

"Ready, Engineer?" asked Arcot.

"Ready, Pilot!" replied Morey.

"All right--just keep your eye on the meters, Dad, as I turn on the
system. If the instruments back there don't take care of everything, and
you see one flash over the red mark--yank open the main circuit. I'll
call out what to watch as I turn them on."

"Ready son."

"Main gyroscopes!" There was a low snap, a clicking of relays in the
rear compartment, and then a low hum that quickly ran up the scale.
"Main generators!" Again the clicking switch, and the relays thudding
into action, again the rising hum. "Seat-gyroscopes." The low click was
succeeded by a quick shrilling sound that rose in moments above the
range of hearing as the separate seat-gyroscopes took up their work.
"Main power tube bank!" The low hum of the generator changed to a
momentary roar as the relays threw on full load. In a moment the
automatic controls had brought it up to speed.

"Everything is working perfectly so far. Are we ready to start now,
son?"

"Main vertical power units!" The great ship trembled throughout its
length as the lift of the power units started. A special instrument had
been set up on the floor beside Arcot, that he might be able to judge
the lift of his power units; it registered the apparent weight of the
ship. It had read two hundred tons. Now all eyes were fixed on it, as
the pointer dropped quickly to 150-100-75-50-40-20-10--there was a
click and the instrument flopped back to 300--it was registering in
pounds now! Then the needle moved to zero, and the mighty structure
floated into the air, slowly moving down the field as a breeze carried
it along the ground.

The men outside saw it rise swiftly into the sky, straight toward the
blue vault of heaven. In two or three minutes it was disappearing. The
glistening ship shrank to a tiny point of light; then it was gone! It
must have been rising at fully three hundred miles an hour!

To the men in the car there had been a tremendous increase in weight
that had forced them into the air cushions like leaden masses. Then the
ground fell away with a speed that made them look in amazement. The
house, the construction shed, the lake, all seemed contracting beneath
them. So quickly were they rising that they had not time to adjust their
mental attitude. To them all the world seemed shrinking about them.

Now they were at a tremendous height; over twenty miles they had risen
into the atmosphere; the air about them was so thin that the sky seemed
black, the stars blazed out in cold, unwinking glory, while the great
fires of the sun seemed reaching out into space like mighty arms seeking
to draw back to the parent body the masses of the wheeling planets.
About it, in far flung streamers of cold fire shone the mighty zodiacal
light, an Aurora on a titanic scale. For a moment they hung there, while
they made readings of the meters.

Arcot was the first to speak and there was awe in his voice. "I never
began to let out the power of this thing! What a ship! When these are
made commercially, we'll have to use about one horsepower generators in
them, or people will kill themselves trying to see how fast they can
go."

Methodically the machine was tried out at this height, testing various
settings of the instruments. It was definitely proven that the values
that Arcot and Morey had assigned from purely theoretical calculations
were correct to within one-tenth of one percent. The power absorbed by
the machine they knew and had calculated, but the terrific power of the
driving units was far beyond their expectations.

"Well, now we're off for some horizontal maneuvers," Arcot announced.
"I'm sure we agree the machine can climb and can hold itself in the air.
The air pressure controls seem to be working perfectly. Now we'll test
her speed."

Suddenly the seats swung beneath them; then as the ship shot forward
with ever greater speed, ever greater acceleration, it seemed that it
turned and headed upward, although they knew that the main stabilizing
gyroscopes were holding it level. In a moment the ship was headed out
over the Atlantic at a speed no rifle bullet had ever known. The radio
speedometer needle pushed farther and farther over as the speed
increased to unheard of values. Before they left the North American
shoreline they were traveling faster than a mile a second. They were in
the middle of the Atlantic before Arcot gradually shut off the
acceleration, letting the seats drop back into position.

A hubbub of excited comments rose from the four men. Momentarily, with
the full realization of the historical importance of this flight, no one
paid any attention to anyone else. Finally a question of the Air
Inspector reached Arcot's ears.

"What speed did we attain, Dr. Arcot? Look--there's the coast of Europe!
How fast are we going now?"

"We were traveling at the rate of three miles a second at the peak."
Arcot answered. "Now it has fallen to two and a half."

Again Arcot turned his attention to his controls. "I'm going to try to
see what the ultimate ceiling of this machine is. It must have a
ceiling, since it depends on the operation of the generator to operate
the power-units. This, in turn, depends on the heat of the air, helped
somewhat by the sun's rays. Up we go!"

The ship was put into a vertical climb, and steadily the great machine
rose. Soon, however, the generator began to slow down. The readings of
the instruments were dropping rapidly. The temperature of the
exceedingly tenuous air outside was so close to absolute zero that it
provided very little energy.

"Get up some forward speed," Morey suggested, "so that you'll have the
aid of the air scoop to force the air in faster."

"Right, Morey." Arcot slowly applied the power to the forward propulsion
units. As they took hold, the ship began to move forward. The increase
in power was apparent at once. The machine started rising again. But at
last, at a height of fifty-one miles, her ceiling had been reached.

The cold of the cabin became unbearable, for every kilowatt of power
that the generator could get from the air outside was needed to run the
power units. The air, too, became foul and heavy, for the pumps could
not replace it with a fresh supply from the near-vacuum outside. Oxygen
tanks had not been carried on this trip. As the power of the generator
was being used to warm the cabin once more, they began to fall. Though
the machine was held stable by the gyroscopes, she was dropping freely;
but they had fifty miles to fall, and as the resistance of the denser
air mounted, they could begin to feel the sense of weight return.

"You've passed, but for the maneuvers, Dr. Arcot!" The Air Inspector was
decidedly impressed. "The required altitude was passed so long ago--why
we are still some miles above it, I guess! How fast are we falling?"

"I can't tell unless I point the nose of the ship down, for the
apparatus works only in the direction in which the ship is pointed. Hold
on, everyone, I am going to start using some power to stop us."

It was night when they returned to the little field in Vermont. They had
established a new record in every form of aeronautical achievement
except endurance! The altitude record, the speed record, the speed of
climb, the acceleration record--all that Arcot could think of had been
passed. Now the ship was coming to dock for the night. In the morning it
would be out again. But now Arcot was sufficiently expert with the
controls to maneuver the ship safely on the ground. They finally solved
the wind difficulty by decreasing the weight of the ship to about fifty
pounds, thus enabling the three men to carry it into the hanger!

       *       *       *       *       *

The next two days were devoted to careful tests of the power factors of
the machine, the best operating frequency, the most efficient altitude
of operation, and as many other tests as they had time for. Each of the
three younger men took turns operating, but so great were the strains of
the sudden acceleration, that Arcot senior decided it would be wisest
for him to stay on the ground and watch.

In the meantime reports of the Pirate became fewer and fewer as less and
less money was shipped by air.

Arcot spent four days practicing the manipulation of the machine, for
though it handled far more readily than any other craft he had ever
controlled, there was always the danger of turning on too much power
under the stress of sudden excitement.

The night before, Arcot had sailed the ship down and alighted on the
roof of Morey senior's apartment, leaving enough power on to reduce the
weight to but ten tons, lest it fall through the roof, while he went
down to see the President of the Lines about some "bait" for the Pirate.

"Send some cash along," said Arcot, when he saw Morey senior, "say a
quarter of a million. Make it more or less public knowledge, and talk it
up so that the Pirate may think there's a real haul on board. I am going
to accompany the plane at a height of about a quarter of a mile above. I
will try to locate him from there by means of radar, and if I have my
apparatus on, I naturally can't locate him. I hope he won't be scared
away--but I rather believe he won't. At any rate, you won't lose on the
try!"




IV


Again Morey and Arcot were looking at the great Jersey aerodrome, out on
the fields that had been broad marshes centuries before. Now they had
been filled in, and stretched for miles, a great landing field, close to
the great city across the river.

The men in the car above were watching the field, hanging inert, a point
of glistening metal, high in the deep velvet of the purple sky, for
fifteen miles of air separated them from the Transcontinental machine
below. Now they saw through their field glasses that the great plane was
lumbering slowly across the field, gaining momentum as it headed
westward into the breeze. Then it seemed to be barely clearing the great
skyscrapers that towered twenty-four hundred feet into the air, arching
over four or five city blocks. From this height they were toys made of
colored paper, soft colors glistening in the hot noon sunlight, and
around and about them wove lines of flashing, moving helicopters, the
individual lost in the mass of the million or so swiftly moving
machines. Only the higher, steadily moving levels of traffic were
visible to them.

"Just look at that traffic! Thousands and thousands coming back into the
city after going home to lunch--and every day the number of helicopters
is increasing! If it hadn't been for your invention of this machine,
conditions would soon be impossible. The airblast in the cities is
unbearable now, and getting worse all the time. Many machines can't get
enough power to hold themselves up at the middle levels; there is a down
current over one hundred miles an hour at the 400-foot level in downtown
New York. It takes a racer to climb fast there!

"If it were not for gyroscopic stabilizers, they could never live in
that huge airpocket. I have to drive in through there. I'm always afraid
that somebody with an old worn-out bus will have stabilizer failure and
will really smash things." Morey was a skillful pilot, and realized, as
few others did, the dangers of that downward airblast that the countless
whirring blades maintained in a constant roar of air. The office
buildings now had double walls, with thick layers of sound absorbing
materials, to stop the roar of the cyclonic blast that continued almost
unabated twelve hours a day.

"Oh, I don't know about that, Morey," replied Arcot. "This thing has
some drawbacks. Remember that if we had about ten million of these
machines hung in the air of New York City, there would be a noticeable
drop in the temperature. We'd probably have an Arctic climate year in
and year out. You know, though, how unbearably hot it gets in the city
by noon, even on the coldest winter days, due to the heating effect of
the air friction of all those thousands of blades. I have known the
temperature of the air to go up fifty degrees. There probably will have
to be a sort of balance between the two types of machines. It will be a
terrific economic problem, but at the same time it will solve the
difficulties of the great companies who have been fermenting grain
residues for alcohol. The castor bean growers are also going to bring
down their prices a lot when this machine kills the market. They will
also be more anxious to extract the carbon from the cornstalks for
reducing ores of iron and of other metals."

As the ship flew high above the Transcontinental plane, the men
discussed the economic values of the different applications of Arcot's
discoveries from the huge power stations they could make, to the cooling
and ventilating of houses.

"Dick, you mentioned the cooling effect on New York City; with the
millions on millions of these machines that there will be, with huge
power plants, with a thousand other different applications in use, won't
the terrific drain of energy from the air cause the whole world to
become a little cooler?" asked Fuller.

"I doubt it, Bob," said Arcot slowly. "I've thought of that myself.
Remember that most of the energy we use eventually ends up as heat
anyway. And just remember the decillions of ergs of energy that the sun
is giving off! True, we only get an infinitesimal portion of that
energy--but what we do get is more than enough for us. Power houses can
be established very conveniently in the tropics, where they will cool
the air, and the energy can be used to refine metals. That means that
the surplus heat of the tropics will find a use. Weather control will
also be possible by the direction-control of great winds. We could set
huge director tubes on the tops of mountains, and blow the winds in
whatever direction best suited us. Not the blown wind itself, but the
vast volume of air it carried with it, would be able to cool the
temperate zones in the summer from the cold of the poles, and warm it in
winter with the heat of the tropics."

After a thoughtful silence, Arcot continued, "And there is another thing
it may make possible in the future--a thing that may be hard to accept
as a commercial proposition. We have a practically inexhaustible source
of energy now, but we have no sources of minerals that will last
indefinitely. Copper is becoming more and more rare. Had it not been for
the discoveries of the great copper fields of the Sahara and in Alaska,
we wouldn't have any now. Platinum is exhausted, and even iron is
becoming more and more valuable. We are facing a shortage of metals. Do
you realize that within the next two centuries we will be unable to
maintain this civilization unless we get new sources of certain basic
raw materials?

"But we have one other chance now. The solution is--there are nine
planets in this solar system! Neptune and Uranus are each far vaster
than Earth; they are utterly impossible for life as we know it, but a
small colony might be established there to refine metals for the distant
Earth. We might be able to build domed and sealed cities. But first we
could try the nearer planets--Mars, Venus, or some satellites such as
our Moon. I certainly hope that this machine will make it possible."

For some time they sat in silence as they sped along, high above the
green plains of Indiana. Chicago lay like some tremendous jewel far off
on the horizon to the right and ahead. Five miles below them the huge
bulk of the Transcontinental plane seemed a toy as it swung slowly
across the fields--actually traveling over six hundred miles an hour.
At last Morey spoke.

"You're right, Arcot. We'll have to think of the interplanetary aspects
of this some day. Oh, there's Chicago! We'd better start the vacuum gas
protector. And the radar. We may soon see some action."

The three men immediately forgot the somewhat distant danger of the
metal shortage. There were a number of adjustments to be made, and these
were quickly completed, while the machine forged evenly, steadily ahead.
The generator was adjusted to maximum efficiency, and the various tubes
were tested separately, for though they were all new, and each good for
twenty-five thousand hours, it would be inconvenient, to say the least,
if one failed while they were in action. Each tested perfect; and they
knew from the smooth functioning of the various relays that governed the
generator, as the loads on it varied, that it must be working perfectly,
at something less than one-half maximum rating.

Steadily they flew on, waiting tensely for the first sign of a glow from
the tiny neon tube indicator on the panel before Morey.

"This looks familiar, Dick," said Morey, looking about at the fields and
the low line of the blue mountains far off on the western horizon. "I
think it was about here that we took our little nap in the 'Flying Wheel
chair', as the papers called it. It would be about here th-- LOOK! It is
about here! Get ready for action, Fuller. You're taking the machine gun,
I'll work the invisibility disrupter, and Arcot will run the ship. Let's
go!"

On the board before him the tiny neon tube flickered dully, glowed
briefly like a piece of red-hot iron, then went out. In a moment it was
glowing again, and then quickly its brilliance mounted till it was a
line of crimson. Morey snapped the switch from the general radar to the
beam receiver, that he might locate the machine exactly. It was fully a
minute before the neon tube flashed into life once more. The pirate was
flying just ahead of the big plane, very likely gassing them. All
around him were the Air Guardsmen, unaware that the enemy was so near.
As the disrupter beam could be projected only about a mile, they would
have to dive down on the enemy at once; an instant later the great plane
beneath them seemed to be rushing upward at a terrific speed.

The two radar beams were kept focused constantly on the Pirate's craft.
When they were about two miles from the two planes, the neon tube blazed
brilliantly with a clash of opposing energy. The Pirate was trying to
maintain his invisibility, while the rapidly growing strength of the
machine above strove to batter it down. In moments the ammeter connected
with the disrupter beam began to rise so rapidly that Morey watched it
with some concern. Despite the ten-kilowatt set being used to project
the beam, the resistance of the apparatus on board the pirate ship was
amazing.

Abruptly the three became aware of a rapidly solidifying cloud before
them. The interference of the beam Morey was sending had begun breaking
down the molecular oscillation that permitted the light to pass freely
through the pirate's craft. Suddenly there was a circle of blue light
about the shadow form, and a moment later the ionized air relapsed into
normal condition as the pirate's apparatus broke down under the strain.
At once Morey shut off his apparatus, convinced by the sudden change
that the pirate's apparatus had blown out. He glanced up quickly as
Arcot called to him, "Morey--look at him go!"

Too late. Already the plane had shot off with terrific speed. It had
flashed up and to their left, at a rate of climb that seemed
unbelievable--except that the long trail of flaming gas told the story!
The plane was propelled by rockets! The terrific acceleration carried it
out of their range of vision in an instant, and as Arcot swung the ship
to bring him again within sight of the windows, they gasped, for already
he was many miles away.

There was a terrific wrench as Arcot threw on all the power he dared,
then quickly leveled the machine, following the pirate at lightning
speed. He increased the acceleration further as the men grew accustomed
to the force that weighed them down. Ahead of them the pirate was racing
along, but quickly now they were overhauling him, for his machine had
wings of a sort! They produced a tremendous amount of head resistance at
their present velocity, for already the needle of the radio speedometer
had moved over to one mile a second. They were following the fleet plane
ahead at the rate of 3600 miles an hour. The roar of the air outside was
a tremendous wave of sound, yet to them, protected by the vacuum of the
double walls, it was detectable only by the vibration of the car.

Rapidly the pirate's lead was cut down. It seemed but a moment before he
would be within range of their machine gun. Suddenly he nosed down and
shot for the ground, ten miles below, in a power dive. Instantly Arcot
swung his machine in a loop that held him close to the tail of the
pirate. The swift maneuvers at this speed were a terrific strain on both
men and machines--the acceleration seemed crushing them with the weight
of four men, as Arcot followed the pirate in a wide loop to the right
that ended in a straight climb, the rocket ship standing on its tail,
the rocket blast roaring out behind a stream of fire a half mile long.

The pirate was climbing at a speed that would have distanced any other
machine the world had ever seen, but the tenacious opponent behind him
clung ever tighter to the tiny darting thing. He had released great
clouds of his animation suspending gas. To his utter surprise, the ship
behind him had driven right through it, entirely unaffected! He, who
knew most about the gas, had been unable to devise a material to stop
it, a mask or a tank to store it, yet in some way these men had
succeeded! And that hurtling, bullet-shaped machine behind! Like some
miniature airship it was, but with a speed and an acceleration that put
even his ship to shame! It could twist, turn, dive, rise and shoot off
on the straight-away with more flashing speed than anything aloft. Time
and again he tried complicated maneuvers that strained him to the
utmost, yet that machine always followed after him!

There was one more thing to do. In outer space his rockets would support
him. In a straight climb he shot up to the blazing sun above, out into
space, while the sky around him grew black, and the stars shone in
solemn splendor around him. But he had eyes for only one thing, the
shining car that was rising with more than equal speed behind him. He
knew he must be climbing over two thousand miles an hour, yet the
tracker came ever closer. Just out of sighting range for the machine gun
now ... in a moment ... but, she was faltering!

The men in the machine behind sat white-lipped, tense, as the whirling
shocks of sudden turns at terrific speed twisted the gyroscopic seats
around like peas in a rolling ball. Up, down, left, right, the darting
machine ahead was twisting with unbelievable speed. Then suddenly the
nose was pointed for the zenith again, and with a great column of flame
shooting out behind him, he was heading straight toward space!

"If he gets there, I lose him, Morey!" said Arcot. The terrific
acceleration of the climb seemed to press them to their seats with a
deadly weight. It was labor to talk--but still the car ahead shot
on--slowly they seemed to be overhauling him. Now that the velocities
were perforce lowered by the effects of gravity, and the air resistance
of the atmosphere was well nigh gone, only the acceleration that the
human body could stand was considered. The man ahead was pushing his
plane ahead with an acceleration that would have killed many men!

Slowly the acceleration of the machine was falling. Arcot pushed the
control over to the last ampere, and felt the slight surge, as greater
power rushed through the coils momentarily. Soon this was gone too, as
the generator behind faltered. The driving power of the atmospheric heat
was gone. More than sixty miles below them they could see the Earth as a
greenish brown surface, slightly convex, and far to the east they could
distinguish a silvery line of water! But they had no eyes but for the
column of shooting flame that represented the fleeing raider! Out in
airless space now, he was safe from them. They could not follow. Arcot
turned the plane once more, parallel to the Earth, watching the plane
above through the roof window. Slowly the machine sank to the fifty-mile
level, where there was just sufficient air to maintain it in efficient
operation.

"Well, he beat us! But there is only one thing for us to do. He must
hang there on his rockets till we leave, and we can hang here
indefinitely, if we can only keep this cabin decently warm. He has no
air to cool him, and he has the sun to warm him. The only thing that is
worrying him right now is the heat of his rockets. But he can throw most
of that out with the gases. Lord, that's some machine! But eventually
his rockets will give out, and down he will come, so we'll just hang
here beneath him and--whoa--not so fast--he isn't going to stay there,
it seems; he is angling his ship off a bit, and shooting along, so that,
besides, holding himself up, he is making a little forward progress.
We'll have to follow! He's going to do some speeding, it seems! Well, we
can keep up with him, at our level."

"Dick, no plane ever made before would have stood the terrific pulls and
yanks that his plane got. He was steering and twisting on the standard
type air rudders, and what strains he had! The unique type of plane must
be extremely strong. I never saw one shaped like his before, though--it
is the obvious shape at that! It was just a huge triangular arrowhead!
Did you ever see one like it?"

"Something like it, yes, and so have you. Don't you recognize that as
the development of the old paper gliders you used to throw around as a
kid? It has the same shape, the triangular wings with the point in the
lead, except that he undoubtedly had a slight curve to the wings to
increase the efficiency. Something like the flying wings of fifty years
ago. I hope that man is only a kleptomaniac, because he can be cured of
that, and I may then have a new laboratory partner. He has some
exceedingly intelligent ideas!

"He's an ingenious man, but I wish he didn't store quite so much fuel
in his rocket tubes! It's unbearably cold in here, and I can't sacrifice
any power just for comfort. The rocket ship up there seems to be getting
more and more acceleration in the level. He has me dropping steadily to
get air to run the generator. He is going fast enough!"

They followed beneath the pirate, faster and faster as the rockets of
the ship began to push it forward more and more.

"Dick, why is it he didn't use all his rockets at first instead of
gradually increasing the power this way?"

"If you were operating the ship, Morey, you'd understand. Look at the
speedometer a moment and see if you can figure it out."

"Hmmm--4.5 miles per second--buzzing right along--but I don't see what
that--good Lord! We never will get him at this rate! How do you expect
to get him?"

"I have no idea--yet. But you missed the important point. He is going
4.5 miles a second. When he reaches 5 miles a second he will never come
down from his hundred and fifty mile high perch! He will establish an
orbit! He has so much centrifugal force already that he has very little
weight. We are staying right beneath him, so we don't have much either.
Well, there he goes in a last spurt. We are falling behind pretty
fast--there we are catching up now--no--we are just holding parallel!
He's done it! Look!"

Arcot pulled out his watch and let go of it. It floated motionless in
the air for a moment, then slowly drifted back toward the rear of the
room. "I am using a bit of acceleration--a bit more than we need to
maintain our speed. We are up high enough to make the air resistance
almost nothing, even at this velocity, but we still require some power.
I don't know--"

There was a low buzz, repeated twice. Instantly Morey turned the dials
of the radio receiving set--again the call signal sounded. In a moment a
voice came in--low, but distinct. The power seemed fading rapidly.

"I'm Wade--the Pirate--help if you can. Can you get outside the
atmosphere? Exceed orbital speed and fall out? Am in an orbit and can't
get out. Fuel reserve gage stuck, and used all my rockets. No more
power. Can not slow down and fall. I am running out of compressed air
and the generator for this set is going--will take animation suspending
gas--will you be able to reach me before entering night?"

"Quick, Morey--answer that we will."

"We will try, Pirate--think we can make it!"

"O.K.--power about gone--"

The last of his power had failed! The pirate was marooned in space! They
had seen his rockets go out, leaving the exhaust tube glowing for a
moment before it, too, was dark, and only the sun shining on the silvery
ship made it visible.

"We have to hurry if we want to do anything before he reaches night!
Radio the San Francisco fields that we will be coming in soon, and we
need a large electro-magnet--one designed to work on about 500 volts
D.C., and some good sized storage cells; how many will have to be
decided later, depending on the room we will have for them. I'll start
decelerating now so we can make the turn and circle back. We are
somewhere west of Hawaii, I believe, but we ought to be able to do the
trick if we use all the power we can."

Morey at once set to work with the radio set to raise San Francisco
airport. He was soon in communication with them, and told them that he
would be there in about an hour. They promised all the necessary
materials; also that they would get ready to receive the pirate once he
was finally brought in to them.

It was nearer an hour and a quarter later that the machine fell to the
great San Francisco landing field, where the mechanics at once set to
work bolting a huge electro-magnet on the landing skids on the bottom of
the machine. The most serious problem was connecting the terminals
electrically without making holes in the hull of the ship. Finally one
terminal was grounded, and the radio aerial used as the other. Fuller
was left behind on this trip, and a large number of cells were installed
in every possible position. In the power room, a hastily arranged motor
generator set was arranged, making it possible to run the entire ship
from the batteries. Scarcely had these been battened down to prevent
sliding under the accelerations necessary, than Arcot and Morey were
off. The entire operation had required but fifteen minutes.

"How are you going to catch him, Arcot?"

"I'll overtake him going west. If I went the other way I'd meet him
going at over 10 miles a second in relation to his machine. He had the
right idea. He told me to fall out to him at a greater than orbital
speed. I will go just within the Earth's atmosphere till I get just
under him, holding myself in the air by means of a downward acceleration
on the part of the regular lifting power units. I am going to try to
reach eight miles a second. We will be overhauling him at three a
second, and the ship will slow down to the right speed while falling out
to him. We must reach him before he gets into the shadow of the Earth,
though, for if he reaches 'night' he will be without heat, and he'll die
of cold. I think we can reach him, Dick!"

"I hope so. Those spare cells are all right, aren't they? We'll need
them! If they don't function when we get out there, we'll fall clear off
into space! At eight miles a second, we would leave Earth forever!"

The ship was accelerating steadily at the highest value the men aboard
could stand. The needle of the speedometer crept steadily across the
dial. They were flying at a height of forty miles that they might have
enough air and still not be too greatly hindered by air resistance. The
black sky above them was spotted with points of glowing light, the
blazing stars of space. But as they flew along, the sensation of weight
was lost; they had reached orbital speed, and as the car steadily
increased its velocity, there came a strange sensation! The Earth loomed
gigantic above them! Below them shone the sun! The direction of up and
down was changed by the terrific speed! The needle of the speedometer
was wavering at 7.8 miles a second. Now it held steady!

"I thought you were going to take it up to eight miles a second, Dick?"

"Air resistance is too great! I'll have to go higher!"

At a height of fifty miles they continued at 8.1 miles a second. It
seemed hours before they reached the spot where the pirate's machine
should be flying directly above them, and they searched the black sky
for some sign of the shining dot of light. With the aid of field glasses
they found it, far ahead, and nearly one hundred miles above.

"Well, here we go! I'm going to fall up the hundred miles or so, till
we're right in his path; the work done against gravity will slow us down
a little, so I'll have to use the power units somewhat. Did you notice
what I did to them?"

"Yes, they're painted a dull black. What's the idea?"

"We'll have no air from which to get heat for power out here, so we'll
have to depend on the sunlight they can absorb. I'm using it now to slow
us down as much as possible."

At last the tiny silver dot had grown till it became recognizable as the
pirate plane. They were drawing up to it now, slowly, but steadily. At
last the little machine was directly beneath them, and a scant hundred
yards away. They had long since been forced to run the machine on the
storage batteries, and now they applied a little power to the vertical
power units. Sluggishly, as they absorbed the sun's heat, the machine
was forced lower, nearer to the machine below. At last a scant ten feet
separated them.

"All right, Morey."

There was a snap, as the temporary switch was closed, and the current
surged into the big magnet on the keel. At once they felt the ship jump
a little under the impulse of the magnet's pull on the smaller machine.
In a moment the little plane had drifted up to the now idle magnet,
touched it and was about to bounce off, when Morey again snapped the
switch shut and the two machines were locked firmly together!

"I've got him, Dick!" Morey exclaimed. "Now slow down till it falls.
Then we can go and wait for it. Being a glider, it ought to be quite
manageable!"

Now the energy of the power units on the roof of the machine began to
slow down the two machines, the magnet grinding slightly as the momentum
of the plane was thrust upon it. They watched the speedometer drop. The
speed was sinking very slowly, for the area of the absorbing fins was
not designed to absorb the sun's heat directly, and was very
inefficient. The sun was indeed sinking below their horizon; they were
just beginning to watch that curious phenomenon of seeing dawn backward,
when they first struck air dense enough to operate the power units
noticeably. Quickly the power was applied till the machines sank rapidly
to the warmer levels, the only governing factor being the tendency of
the glider to break loose from the grip of the magnet.

At fifty miles the generator was started, and the heaters in the car at
once became more active. There was no heat in the car below, but that
was unavoidable. They would try to bring it down to warm levels quickly.

"Whew, I'm glad we reached the air again, Dick. I didn't tell you
sooner, for it wouldn't have done any good, but that battery was about
gone! We had something like twenty amp-hours left! I'm giving the
recharge generator all she will take. We seem to have plenty of power
now."

"I knew the cells were low, but I had no idea they were as low as that!
I noticed that the magnet was weakening, but thought it was due to the
added air strain. I am going to put the thing into a nose dive and let
the glider go down itself. I know it would land correctly if it had a
chance. I am going to follow it, of course, and since we are over the
middle of Siberia we'd better start back."

The return trip was necessarily in the lower level of the atmosphere,
that the glider might be kept reasonably warm. At a height of but two
miles, in the turbulent atmosphere, the glider was brought slowly home.
It took them nearly twenty hours to go the short distance of twelve
thousand miles to San Francisco, the two men taking turns at the
controls. The air resistance of the glider forced them to go slowly;
they could not average much better than six hundred an hour despite the
fact that the speed of either machine alone was over twelve hundred
miles an hour.

At last the great skyscrapers of San Francisco appeared on their
horizon, and thousands of private planes started out to meet them.
Frantically Arcot warned them away, lest the air blast from their props
tear the glider from the magnet. At last, however, the Air Guard was
able to force them to a safe distance and clear a lane through one of
the lower levels of the city traffic. The great field of the
Transcontinental lines was packed with excited men and women, waiting to
catch a glimpse of two of the greatest things the country had heard of
in the century--Arcot's molecular motion machine and the Air Pirate!

The landing was made safely in the circle of Air Guardsmen. There was a
small hospital plane standing beside it in a moment, and as Arcot's ship
released it, and then hung motionless, soundless above it, the people
watched it in wonder and excitement. They wanted to see Arcot perform;
they clamored to see the wonderful powers of this ship in operation. Air
Guardsmen who had witnessed the flying game of tag between these two
super-air machines had told of it through the press and over the radio.

       *       *       *       *       *

Two weeks later, Arcot stepped into the office of Mr. Morey, senior.

"Busy?"

"Come on in; you know I'm busy--but not _too_ busy for you. What's on
your mind?"

"Wade--the pirate."

"Oh--hmm. I saw the reports on his lab out on the Rockies, and also the
psychomedical reports on him. And most particularly, I saw the request
for his employment you sent through channels. What's your opinion on
him? You talked with him."

Arcot frowned slightly. "When I talked to him he was still two different
identities dancing around in one body. Dr. Ridgely says the problem's
settling down; I believe him. Ridgely's no more of a fool in his line
than you and Dad are in your own lines, and Ridgely's business is
healing mental wounds. We agreed some while back that the Pirate must be
insane, even before we met him.

"We also agreed that he had a tremendously competent and creative mind.
As a personality in civilization, he'd evidently slipped several cogs.
Ridgely says that is reparable.

"You know, Newton was off the beam for about two years. Faraday was in a
complete breakdown for nearly five years--and after his breakdown, came
back to do some monumental work.

"And those men didn't have the help of modern psychomedical techniques.

"I think we'd be grade A fools ourselves to pass up the chance to get
Wade's help. The man--insane or not--figured out a way of stabilizing
and storing atomic hydrogen for his rockets. If he could do that in the
shape he was then in...!

"I'd say we'd be smart to keep the competition in the family."

Mr. Morey leaned back in his chair and smiled up at Arcot. "You've got a
good case there. I'll buy it. When Dr. Ridgely says Wade's got those
slipped cogs replaced--offer him a job in your lab staff.

"I'm a bit older than you are; you've grown up in a world where the
psychomedical techniques really work. When I was growing up,
psychomedical techniques were strictly rule of thumb--and the doctors
were all thumbs." Mr. Morey sighed. Then, "In this matter, I think your
judgment is better than mine."

"I'll see him again, and offer him the job. I'm pretty sure he'll take
it, as I said. I have a suspicion that, within six months, he'll be a
lot saner than most people around. The ordinary man doesn't realize what
a job of rechecking present techniques can do--and Wade is, naturally,
getting a very thorough overhaul.

"Somewhat like a man going in for treatment of a broken arm; in any
decent hospital they'll also check for any other medical problems, and
he'll come out healthier than if he had never had the broken arm.

"Wade seems to have had a mind that made friends with molecules, and
talked their language. After Ridgely shows him how to make friends with
people--I think he'll be quite a man on our team!"




BOOK TWO

SOLARITE




I


The lights of great Transcontinental Airport were blazing in cheering
splendor. Out there in the center of the broad field a dozen men were
silhouetted in the white brilliance, looking up at the sky, where the
stars winked cold and clear on the jet background of the frosty night. A
slim crescent of moon gleamed in the west, a sickle of light that in no
way dimmed the cold flame of the brilliant stars.

One point of light now moved across the motionless field of far-off
suns, flashing toward the airport in a long, swift curve. The men on the
field murmured and pointed up at it as it swept low over the blazing
lights of New York. Lower it swooped, the towering city behind it. Half
a mile into the air the buildings rose in shining glory of colored tile
that shone brightly in the sweeping play of floodlights.

One of them picked out the descending machine, and it suddenly leaped
out of the darkness as a shining, streamlined cylinder, a cylinder with
a great halo of blue fire, as the beam of the searchlight set it off
from the jet black night.

In moments the ship was vast before the eyes of the waiting men; it had
landed gently on the field, was floating smoothly, gracefully toward
them.

Twenty-four men climbed from the great ship, shivering in the icy blast
that swept across the field, spoke a moment with the group awaiting
their arrival, then climbed quickly into the grateful warmth of a field
car. In a moment they were speeding toward the lights of the field
house, half a mile off.

Behind them the huge ship leaped into the sky, then suddenly pointed its
nose up at an angle of thirty degrees and shot high into the air at an
unbelievable speed. In an instant it was gone.

At the field house the party broke up almost immediately.

"We want to thank you, Mr. Morey, for your demonstration of the new ship
tonight, and you, Dr. Arcot, for answering our many questions about it.
I am sure we all appreciate the kindness you have shown the press." The
reporters filed out quickly, anxious to get the news into the morning
editions, for it was after one o'clock now. Each received a small slip
of paper from the attendant standing at the exit, the official statement
of the company. At last all had left but the six men who were
responsible for the new machine.

This night had witnessed the official demonstration of the first of the
Arcot-Morey molecular motion ships. Small as she was, compared to those
that were to come, yet she could carry over three thousand passengers,
as many as could any existing winged plane, and her speed was immensely
greater. The trip from the west coast to the eastern had been made in
less than one hour. At a speed close to one mile a second the great ship
had shot through the thin air, twenty-five miles above the Earth.

In this vessel a huge bar of metal could be affected by an
ultra-high-frequency generator. When so affected, its molecules all
moved forward, taking the ship with them. Thus, a molecular motion drive
vessel could, theoretically, approach the velocity of light as a limit.

"Arcot," said Morey, Senior, after the pressmen had left the room, "as
president of this company I certainly want to thank you for the
tremendous thing you have given us to use. You have 'sold' us this
machine--but how can we repay you? Before this, time and time again,
you have sold us your inventions, the ideas that have made it possible
for Transcontinental to attain its present high position in world
transportation. All you have ever accepted is the laboratory you use,
its upkeep, and a small annual income. What can we do to show our
appreciation this time?"

"Why," answered Arcot smiling, "you haven't stated the terms correctly.
Actually, I have a fully equipped lab to putter around in, all the time
I want for my own amusement, and all the money I want. What more could I
ask?"

"I suppose that's all true--but you draw only about six thousand a year
for personal expenses--a good clerk could get that--and you, admittedly
the most brilliant physicist of the Earth, are satisfied! I don't feel
we're paying you properly!"

Arcot's expression became suddenly serious. "You can repay me this
time," he said, "for this latest discovery has made a new thing
possible. I've always wanted to be able to visit other planets--as has
many a scientist for the last three centuries. This machine has made it
possible. If you are willing--we could start by the spring of 2117. I'm
quite serious about this. With your permission, I want to start work on
the first interplanetary ship. I'll need Fuller's help, of course. The
proposition will be expensive, and that's where I must ask you to help
me. I think, however, that it may be a paying proposition, at that, for
there will certainly be something of commercial value on the other
planets."

They had walked out to the shed where Arcot's private molecular motion
car stood, the first machine ever built that used the heat of the sun to
drive it. Thoughtfully the president of the great Transcontinental Lines
looked at it. It was small compared with the great machine that had just
brought them east, but of the same swift type. It was a thing of
graceful beauty even on the ground, its long curving streamlines giving
it wonderful symmetry. They stood in thoughtful silence for a
minute--the young men eager to hear the verdict of their prospective
backer. Morey, always rather slow of speech, took an unusually long
time to answer.

"If it were only money you asked for, Arcot, I'd gladly give you double
the sum, but that isn't the case. I know perfectly well that if you do
go, my son will go with you, and Fuller and Wade will naturally go too."
He looked at each in turn. "Each of you has come to mean a lot to me.
You and Fuller have known Bob since college days. I've known Wade only
three months, but every day I grow to like him more. There's no denying
the fact that any such trip is a terrifically dangerous proposition. But
if you were lost, there would be more than my personal loss. We would
lose some of the most brilliant men on Earth. You, for instance, are
conceded as being the world's most brilliant physicist; Fuller is one of
the greatest designing engineers; Wade is rapidly rising into prominence
as a chemist and as a physicist; and my son is certainly a good
mathematician."

He paused, frowning, weighing the situation. "But you men should know
how to get out of scrapes just that much better. Certainly there are few
men on Earth who would not be willing to back such a group of men--or
any one of you, for that matter! I'll back your trip!" His words became
more facetious. "I know that Arcot and you, Bob, can handle a gun fairly
well, I don't know so much about Wade and Fuller. What experience have
you two had?"

Fuller shook his head. "I think I'll fit best in the galley on the trip,
Mr. Morey. I've done the cooking on a number of camping trips, and food
is an important factor in the success of any expedition. I can shoot a
bit, too."

Wade spoke rather hesitantly. "I come from the west, and have had a good
bit of fun with a gun in the Rockies; there are still some mountain
lions and some deer there, you know. I also have a sneaking acquaintance
with the new gun, which Arcot developed in connection with his molecular
motion. But there is so little you know about me--and most of it bad--I
don't see how I really get in on this opportunity--but," he added
hastily, "I certainly don't intend to keep the old boy knocking--I'm
with you, since I'm invited!"

Arcot smiled. "Then you'll definitely support us?"

"Yes, I will," replied Morey, Senior, seriously, "for I think it's worth
doing."

The four young men climbed into the ship, to start for their apartment.
Arcot was piloting, and under his sure touch the ship sped out into the
cold night air, then up through the atmosphere, till they hung poised at
a height of fifty miles on the upper edge of the airy blanket. They
looked out in silent thought at the magnificent blazing stars of space.
Here, where the dust-laden air could no longer mask their true colors,
the stars shone unwinkingly, steadily, and in a glory that earth-bound
men had never seen before. They shone in a wonderous riot of color, as
varied and as beautiful as the display of colored floodlights in some
great city. They were tiny pinpoints of radiance, red, green, orange,
and yellow, shining with intense brilliance.

Slowly Arcot let the machine settle to the blazing city miles below.

"I love to come out here and look at those cold, pinpoint lights; they
seem to draw me--the lure of other worlds. I've always had a sense of
unfulfilled longing--the desire to go out there--and it's always been so
hopeless. Now--I'll be out there by next spring!" Arcot paused and
looked up at the mighty field of stars that arched over his head to be
lost on either horizon. A wonderful night!

"Where shall we go first, Dick?" asked Wade softly as he gazed out at
the far-off suns of space, his voice unconsciously hushed by the
grandeur of the spectacle.

"I've thought of that for the last four months, and now that we are
definitely going to go, we'll have to make a decision. Actually, it
won't be too hard to decide. Of course we can't leave the solar system.
And the outer planets are so far away that I think we had better wait
till later trips. That leaves the choice really between Mars, Venus, and
Mercury. Mercury isn't practical since it's so close to the sun. We know
a fair bit about Mars from telescopic observation, while Venus, wrapped
in perpetual cloud, is a mystery. What do you vote?"

"Well," said Morey, "it seems to me it's more fun to explore a
completely unknown planet than one that can be observed telescopically.
I vote Venus." Each of the others agreed with Morey that Venus was the
logical choice.

By this time the machine had sunk to the roof of their apartment, and
the men disembarked and entered. The next day they were to start the
actual work of designing the space ship.




II


"When we start this work," Arcot began next morning, "we obviously want
to design the ship for the conditions we expect to meet, and for maximum
convenience and safety. I believe I've thought about this trip longer
than the rest of you, so I'll present my ideas first.

"We don't actually _know_ anything about conditions on Venus, since no
one has actually been there. Venus is probably a younger planet than
Earth. It's far nearer the sun than we are, and it gets twice the heat
we do. In the long-gone time when the planets were cooling I believe
Venus required far longer than Earth, for the inpouring heat would
retard its cooling. The surface temperature is probably about 150
degrees Fahrenheit.

"There is little land, probably, for with the cloud-mass covering Venus
as it does, it's logical to visualize tremendous seas. What life has
developed must be largely aquatic, and the land is probably far behind
us in evolution. Of course, Venus is the planet of mystery--we don't
know; we can only guess. But we do know what things we are going to need
to cross space.

"Obviously, the main driving force will be the power units. These will
get their energy from the rays of the sun by absorbing them in copper
discs about twelve feet in diameter--the ship will have to be more of a
disc than a cylinder. I think a ship a hundred and eighty feet long,
fifty feet wide, and twenty feet deep will be about the best dimensions.
The power units will be strung along the top of the ship in double
rows--one down each side of the hull. In the middle will be a series of
fused quartz windows, opening into a large room just under the outer
shell. We'll obviously need some source of power to activate the power
tubes that run the molecular motion power units. We'll have a generator
run by molecular motion power units in here, absorbing its heat from the
atmosphere in this room. The air will be heated by the rays of the sun,
of course, and in this way we'll get all our power from the sun itself.

"Since this absorption of energy might result in making the ship too
cool, due to the radiation of the side away from the sun, we'll polish
it, and thus reduce the unlighted side's radiation.

"The power units will not be able to steer us in space, due to their
position, and those on the sides, which will steer us in the atmosphere
by the usual method, will be unable to get the sun's power; they'll be
shaded. For steering in space, we'll use atomic hydrogen rockets,
storing the atomic gas by the Wade method in tanks in the hold. We'll
also have a battery down there for starting the generator and for
emergencies.

"For protection against meteors, we'll use radar. If anything comes
within a dozen miles of us, the radar unit covering that sector will at
once set automatic machinery in operation, and the rockets will shoot
the ship out of the path of the meteor."

All that day Arcot and the others discussed the various pieces of
apparatus they would need, and toward evening Fuller began to draw rough
sketches of the different mechanisms that had been agreed upon.

The next day, by late afternoon, they had planned the rough details of
the ship and had begun the greater task of calculating the stresses and
the power factors.

"We won't need any tremendous strength for the ship while it is in
space," Arcot commented, "for then there will be little strain on it.
It will be weightless from the start, and the gentle acceleration will
not strain it in the least, but we must have strength, so that it can
maneuver in the atmosphere.

"We'll leave Earth by centrifugal force, for I can make much better
speed in the atmosphere where there is plenty of power to draw on;
outside I must depend solely on sunlight. We'll circle the Earth,
forming an orbit just within the atmosphere, at five miles a second.
We'll gradually increase the speed to about ten miles a second, at which
point the ship would normally fly off into space under its own
centrifugal force. With the power units we'll prevent its release until
the proper moment. When we release it, it will be entirely free of
Earth, and no more work will be needed to overcome Earth's pull."

The planning continued with exasperating slowness. The details of the
work were complex, for all the machines were totally new. Several weeks
passed before even the power units could be ordered and the first work
on the ship started. After that orders for materials left the office
daily. Still, it was late in November before the last order was sent
out.

Now they must begin work on other phases of the expedition--food
supplies and the standard parts of the equipment.

In the interval Arcot had decided to make a special ventilated suit for
use on Venus. This was to make use of a small molecular motion director
apparatus to cool the air, and blow it through the suit. The apparatus
consisted of a small compressed air-driven generator and a power tube
bank that could be carried on the back.

"Arcot," Wade said when he saw the apparatus completed and the testing
machine ready, "I've just noticed how similar this is to the portable
invisibility apparatus I developed as the Pirate. I wonder if it might
not be handy at times to be invisible--we could incorporate that with a
slight change. It wouldn't add more than five pounds, and those tubes
you are using I'm sure are easily strong enough to carry the extra
load."

"Great idea, Wade," said Arcot. "It might be very useful if we met
hostile natives. The disappearance stunt might make us gods or something
to primitive beings. And now that you mention it, I think we can install
the apparatus in the ship. It will require almost no power, and might
save our lives some time."

The work went forward steadily at the great Transcontinental Shops where
the space ship was being built. Its construction was being kept as much
of a secret as possible, for Arcot feared the interference of the crowds
that would be sure to collect if the facts were known, and since the
shops directly joined the airfield, it meant that there would be
helicopters buzzing about the Transatlantic and Transcontinental planes.

The work to be done required the most careful manipulation and
workmanship, for one defect could mean death. They calculated six weeks
for the trip, and in the time before they could reach either planet,
much might happen to a crippled ship.

To the men who were making the trip, the waiting seemed most
exasperating, and they spent the days before they could begin the
installation of the electrical apparatus in purchasing the necessary
standard equipment; the standard coils, tubes, condensers, the canned
food supplies, clothes, everything that they could imagine as of
possible utility. They were making the ship with a great deal of empty
storage space, for Arcot hoped the trip would be a financial success,
particularly supplying much-needed metals. Many vital elements were
already excessively scarce, and no satisfactory substitutes had been
found.

On the outward trip some of this space would be filled with the many
things they would consume en route. In addition they were carrying a
great many spare parts, spare tubes, spare power units, spare
condensers--a thousand and one odd parts. Arcot intended that they
should be able to make an entire new power switchboard and motion
director unit if anything should go wrong, and he certainly had all the
apparatus.

At last came the day when the final connection had been soldered, and
the last joint welded. The atomic hydrogen tanks were full, and under
the ship's own power the oxygen tanks were filled and the batteries
charged. They were ready for a test flight!

The great ship rested on the floor of the shed now, awaiting the start.

"Oh fellows--come here a minute!" Arcot called to the other members of
the party. "I want to show you something."

The three walked quickly to the bow where Arcot stood, and following the
line of his vision, looked in wonder to see that everything was right.
They watched curiously as he drew from his coat a large glass bottle,
tightly sealed.

"What's that for?" asked Wade curiously.

"We're about to start on the first cruise, and I've been wondering if it
isn't time we gave the ship a name."

"Great--I'd been thinking of that too--what are we going to name her?"

"Well," said Arcot, "I had been thinking of Alexander--he longed for
other worlds to conquer!"

"Not bad," Morey commented. "I have been thinking of naming it too--I
guess we all have--but I was thinking of Santa Maria--the first ship to
discover the New World."

"I was thinking more of its home," said Wade. "How about calling it
Terrestrian?"

"Well--it's your turn, Fuller--you designed it. What do you suggest for
your masterpiece?" asked Arcot.

"I was thinking also of its home--the home it will never leave. I like
to think that we might find people on Venus, and I would like to have a
name on it that might be translatable into more friendly and less
foreign terms--why not call it Solarite?"

"Solarite--a member of the solar system--it will be that, always. It
will be a world unto itself when it makes its trips--it will take up an
orbit about the sun--a true member of the solar system. I like it!"
Arcot turned to the others. "How about it?" It was agreed upon
unanimously.

"But I'm still curious about that glass bottle, so carefully sealed."
Morey commented with a puzzled smile. "What's in it? Some kind of gas?"

"Wrong--no gas--practically nothing at all, in fact. What more
appropriate for christening a space ship than a bottle of hard vacuum?

"We can't have a pretty girl christen this ship, that's sure. A flying
bachelor's apartment christened by a mere woman? Never! We will have the
foreman of the works here do that. Since we can't have the ship slide
down the ways or anything, we will get inside and move it when he
smashes the bottle. But in the meantime, let's have a symbol set in
contrasting metal on the bow. We can have a blazing sun, with nine
planets circling it, the Earth indicated conspicuously; and below it the
word SOLARITE."




III


It was shortly after noon when the newly christened _Solarite_ left on
its first trip into space. The sun was a great ball of fire low in the
west when they returned, dropping plummet-like from the depths of space,
the rush of the air about the hull, a long scream that mounted from a
half-heard sound in the outer limits of the Earth's atmosphere, to a
roar of tortured air as the ship dropped swiftly to the field and shot
into the hanger. Instantly the crew darted to the side of the great
cylinder as the door of the ship opened.

Fuller appeared in the opening, and at the first glimpse of his face,
the hanger crew knew something was wrong. "Hey, Jackson," Fuller called,
"get the field doctor--Arcot had a little accident out there in space!"
In moments the man designated returned with the doctor, leading him
swiftly down the long metal corridor of the _Solarite_ to Arcot's room
aboard.

There was a mean-looking cut in Arcot's scalp, but a quick, sure
examination by the doctor revealed that there appeared to be no serious
injury. He had been knocked unconscious by the blow that made the cut,
and he had not yet recovered his senses.

"How did this happen?" asked the doctor as he bathed the cut and deftly
bandaged it.

Morey explained: "There's a device aboard whose job it is to get us out
of the way of stray meteors, and it works automatically. Arcot and I
were just changing places at the controls. While neither of us was
strapped into our seats, a meteor came within range and the rocket tubes
shot the car out of the way. We both went tumbling head over heels and
Arcot landed on his ear. I was luckier, and was able to break my fall
with my hands, but it was a mean fall--at our speed we had about double
weight, so, though it was only about seven feet, we might as well have
fallen fourteen. We took turns piloting the ship, and Arcot was about to
bring us back when that shock just about shook us all over the ship. We
will have to make some changes. It does its job--but we need warning
enough to grab hold."

The doctor was through now, and he began to revive his patient. In a
moment he stirred and raised his hand to feel the sore spot. In ten
minutes he was conversing with his friends, apparently none the worse
except for a very severe headache. The doctor gave him a mild opiate,
and sent him to bed to sleep off the effects of the blow.

       *       *       *       *       *

With the ship fully equipped, tested and checked in every possible way,
the time for leaving was set for the following Saturday, three days off.
Great supplies of stores had to be carried aboard in the meantime. Care
had to be exercised in this work, lest the cargo slip free under varying
acceleration of the _Solarite_, and batter itself to bits, or even wreck
some vital part of the ship. At noon on the day chosen, the first ship
ever to leave the bounds of the Earth's gravity was ready to start!

Gently the heavily laden _Solarite_ rose from the hangar floor, and
slowly floated out into the bright sunshine of the early February day.
Beside it rode the little ship that Arcot had first built, piloted by
the father of the inventor. With him rode the elder Morey and a dozen
newsmen. The little ship was badly crowded now as they rose slowly, high
into the upper reaches of the Earth's atmosphere. The sky about them
was growing dark--they were going into space!

At last they reached the absolute ceiling of the smaller ship, and it
hung there while the _Solarite_ went a few miles higher; then slowly,
but ever faster and faster they were plunging ahead, gathering speed.

They watched the radio speedometer creep up--1-2-3-4-5-6--steadily it
rose as the acceleration pressed them hard against the back of the
seats--8-9--still it rose as the hum of the generator became a low
snarl--10-11-12--they were rocketing at twelve miles a second, the
tenuous air about the ship shrieking in a thin scream of protest as it
parted on the streamlined bow.

Slowly the speed rose--reached fifteen miles a second. The sun's pull
became steadily more powerful; they were falling toward the fiery
sphere, away from the Earth. A microphone recessed in the outer wall
brought them the fading whisper of air from outside. Arcot shouted a
sudden warning:

"Hold on--we're going to lose all weight--out into space!"

There was a click, and the angry snarl of the overworked generator died
in an instant as the thudding relays cut it out of the circuit.
Simultaneously the air scoop which had carried air to the generator
switched off, transferring to solar heat as a source of power. They
seemed to be falling with terrific and ever-increasing speed. They
looked down--saw the Earth shrinking visibly as they shot away at more
than five miles a second; they were traveling fifteen miles a second
ahead and five a second straight up.

The men watched with intensest interest as the heavens opened up before
them--they could see stars now a scant degree from the sun itself, for
no air diffused its blinding glory. The heat of the rays seemed to burn
them; there was a prickling pleasantness to it now, as they looked at
the mighty sea of flame through smoked glasses. The vast arms of the
corona reached out like the tentacles of some fiery octopus through
thousands of miles of space--huge arms of flaming gas that writhed out
as though to reach and drag back the whirling planets to the parent
body. All about the mighty sphere, stretching far into space, a wan glow
seemed to ebb and flow, a kaleidoscope of swiftly changing color. It was
the zodiacal light, an aurora borealis on a scale inconceivable!

Arcot worked rapidly with the controls, the absence of weight that gave
that continued sense of an unending fall, aiding him and his assistants
in their rapid setting of the controls.

At last the work was done and the ship flashed on its way under the
control of the instruments that would guide it across all the millions
of miles of space and land it on Venus with unerring certainty. The
photo-electric telescopic eye watched the planet constantly, keeping the
ship surely and accurately on the course that would get them to the
distant planet in the shortest possible time.

Work thereafter became routine requiring a minimum of effort, and the
men could rest and use their time to observe the beauties of the skies
as no man had ever seen them during all the billions of years of time
that this solar system has existed. The lack of atmosphere made it
possible to use a power of magnification that no terrestrial telescope
may use. The blurred outlines produced by the shifting air prohibits
magnifications of more than a few hundred diameters, but here in space
they could use the greatest power of their telescope. With it they could
look at Mars and see it more clearly than any other man had ever seen
it, despite the fact that it was now over two hundred million miles
away.

But though they spent much time taking photographs of the planets and of
the moon, and in making spectrum analyses of the sun, time passed very
slowly. Day after day they saw measured on the clocks, but they stayed
awake, finding they needed little sleep, for they wasted no physical
energy. Their weightlessness eliminated fatigue. However, they
determined that during the twelve hours before reaching Venus they must
be thoroughly alert, so they tried to sleep in pairs. Arcot and Morey
were the first to seek slumber--but Morpheus seemed to be a mundane god,
for he did not reward them. At last it became necessary for them to
take a mild opiate, for their muscles refused to permit their tired
brains to sleep. It was twelve hours later when they awoke, to relieve
Wade and Fuller.

They spent most of the twelve hours of their routine watch in playing
games of chess. There was little to be done. The silver globe before
them seemed unchanging, for they were still so far away it seemed little
larger than the moon does when seen from Earth.

But at last it was time for the effects of the mild drug to wear off,
and for Wade and Fuller to awaken from their sleep.

"Morey--I've an idea!" There was an expression of perfect innocence on
Arcot's face--but a twinkle of humor in his eyes. "I wonder if it might
not be interesting to observe the reactions of a man waking suddenly
from sleep to find himself alone in space?" He stared thoughtfully at
the control that would make the ship perfectly transparent, perfectly
invisible.

"I wonder if it would?" said Morey grasping Arcot's idea. "What do you
say we try it?" Arcot turned the little switch--and where there had been
the ship, it was no more--it was gone!

Fuller stirred uneasily in his bed, tightly strapped as he was. The
effects of the drug were wearing off. Sleepily he yawned--stretched, and
blindly, his heavy eyes still closed, released the straps that held him
in bed. Yawning widely he opened his eyes--with a sudden start sat
upright--then, with an excellent imitation of an Indian on the warpath,
he leaped from his bed, and started to run wildly across the floor. His
eyes were raised to the place where the ceiling should have been--he
called lustily in alarm--then suddenly he was flying up--and crashed
heavily against the invisible ceiling! His face was a picture of utter
astonishment as he fell lightly to the floor--then slowly it changed,
and took on a chagrined smile--he understood!

He spun around as loud cries suddenly resounded from Wade's room across
the hall--then there was a dull thud, as he too, forgetting the
weightlessness, jumped and hit the ceiling. Then the cries were gone,
like the snuffing of a candle. From the control room there rose loud
laughter--and a moment later they felt more normal, as they again saw
the four strong walls about them.

Wade sighed heavily and shook his head.

They were approaching the planet visibly now. In the twelve hours that
had passed they had covered a million miles, for now they were falling
toward the planet under its attraction. It glowed before them now in
wonderous splendour, a mighty disc of molten silver.

For the last twenty-four hours they had been reducing their speed
relative to Venus, to insure their forming an orbit about the planet,
rather than shoot around it and back into space. Their velocity had been
over a hundred miles a second part of the way, but now it had been
reduced to ten. The gravity of the planet was urging them forward at
ever increasing speed, and their problem became more acute moment by
moment.

"We'll never make it on the power units alone, out here in space," said
Arcot seriously. "We'll just shoot around the planet. I'll tell you how
we can do it, though. We'll circle around it, entering its atmosphere on
the daylight side, and shoot into the upper limits of its atmosphere.
There the power units can find some heat to work on, and we can really
slow down. But we'll have to use the rocket tubes to get the
acceleration we'll need to drive the ship into the air."

There was a sudden clanging of a bell, and everyone dived for a hold,
and held on tightly. An instant later there was a terrific wrench as the
rocket jets threw the plane out of the way of a meteor.

"We're getting near a planet. This is the third meteor we've met since
we were more than a million miles from Earth. Venus and Earth and all
the planets act like giant vacuum cleaners of space, pulling into
themselves all the space debris and meteors within millions of miles by
their gravitational attraction."

Swiftly the planet expanded below them--growing vaster with each passing
moment. It had changed from a disc to a globe, and now, as the molten
silver of its surface seemed swiftly clouding, it turned grey; then they
saw its true appearance, a vast field of rolling, billowing clouds!

The _Solarite_ was shooting around the planet now at ten miles a second,
far more than enough to carry them away from the planet again, out into
space once more if their speed was not checked.

"Hold on everybody," Arcot called. "We're going to turn toward the
planet now!" He depressed a small lever--there was a sudden shock, and
all the space about them seemed to burst into huge, deep-red atomic
hydrogen flames.

The _Solarite_ reeled under the sudden pressure, but the heavy
gyroscopic stabilizers caught it, held it, and the ship remained on an
even keel. Then suddenly there came to the ears of the men a long drawn
whine, faint--almost inaudible--and the ship began slowing down. The
_Solarite_ had entered the atmosphere of Venus--the first man-made
machine to thus penetrate the air of another world!

Quickly Arcot snapped open the control that had kept the rockets
flaming, turning the ship to the planet--driving it into the atmosphere.
Now they could get their power from the air that each instant grew more
dense about them.

"Wade--in the power room--emergency control post--Morey--control board
there--hang on, for we'll have to use some husky accelerations."

Instantly the two men sprang for their posts--literally diving, for they
were still almost weightless.

Arcot pulled another lever--there was a dull snap as a relay in the
power room responded--the lights wavered--dimmed--then the generator was
once more humming smoothly--working on the atmosphere of Venus! In a
moment the power units were again operating, and now as they sucked a
plentitude of power from the surrounding air, they produced a force that
made the men cling to their holds with almost frantic force. Around them
the rapidly increasing density of the air made the whine grow to a roar;
the temperature within the ship rose slowly, warmed by friction with
the air, despite the extreme cold at this altitude, more than
seventy-five miles above the surface of the planet.

They began dropping rapidly now--their radio-speedometer had fallen from
ten to nine--then slowly, but faster and faster as more heat could be
extracted from the air, it had fallen 8--7--6--5--4. Now they were well
below orbital speed, falling under the influence of the planet. The
struggle was over--the men relaxed. The ship ran quietly now, the smooth
hum of the air rushing over the great power units coming softly through
the speaker to their ears, a humming melody--the song of a new world.




IV


Suddenly the blazing sun was gone and they were floating in a vast world
of rolling mists--mists that brushed the car with tiny clicks, which,
with the millions of particles that struck simultaneously, merged into a
steady roar.

"Ice--ice clouds!" Morey exclaimed.

Arcot nodded. "We'll drop below the clouds; they're probably miles deep.
Look, already they're changing--snow now--in a moment it will be
water--then it'll clear away and we'll actually see Venus!"

For ten miles--an endless distance it seemed--they dropped through
clouds utterly impenetrable to the eye. Then gradually the clouds
thinned; there appeared brief clear spots, spots into which they could
see short distances--then here and there they caught glimpses of green
below. Was it water--or land?

With a suddenness that startled them, they were out of the clouds,
shooting smoothly and swiftly above a broad plain. It seemed to stretch
for endless miles across the globe, to be lost in the far distance to
east and west; but to the north they saw a low range of hills that rose
blue and misty in the distance.

"Venus! We made it!" Morey cried jubilantly. "The first men ever to
leave Earth--I'm going to start the old sender and radio back home!
Man--look at that stretch of plain!" He jumped to his feet and started
across the control room. "Lord--I feel like of ton of lead now--I sure
am out of condition for walking after all that time just floating!"

Arcot raised a restraining hand. "Whoa--wait a minute there, Morey--you
won't get anything through to them now. The Earth is on the other side
of Venus--it's on the night side, remember--and we're on the day side.
In about twelve hours we'll be able to send a message. In the meantime,
take the controls while I make a test of the air here, will you?"

Relieved of the controls, Arcot rose and walked down the corridor to the
power room where the chemical laboratory had been set up. Wade had
already collected a dozen samples of air, and was working on them.

"How is it--what have you tested for so far?" asked Arcot.

"Oxygen and CO_{2}. The oxygen is about twenty-two per cent, or
considering the slightly lower air pressure here, we will have just
about the right amount of oxygen. The CO_{2} is about one-tenth of one
per cent. The atmosphere is O.K. for terrestrial life apparently; that
mouse there is living quite happily. Whatever the other seventy-five per
cent or so of diluting gas is, I don't know, but it isn't nitrogen."

Briefly Arcot and Wade discussed the unusual atmosphere, finally
deciding that the inert gas was argon.

"No great amount of nitrogen," Arcot concluded. "That means that life
will have a sweet time extracting it from the air--but wherever there is
life, it finds a way to do the impossible. Test it more accurately, will
you--you try for nitrogen and I'll try the component inert gasses."

They ran the analyses rapidly, and in a very short time--less than an
hour--their results stood at 23 per cent oxygen, .1 per cent carbon
dioxide, 68 per cent argon, 6 per cent nitrogen, 2 per cent helium, 5
per cent neon, .05 per cent hydrogen, and the rest krypton and xenon
apparently. The analyses of these inert gasses had to be done rather
roughly in this short time, but it was sufficient to balance fairly
accurately.

The two chemists reported back to the control cabin.

"Well, we'll be able to breathe the atmosphere of Venus with ease. I
believe we can go on now. I have been surprised to see no water in
sight, but I think I see my mistake now. You know the Mississippi has
its mouth further from the center of the Earth than its source; it flows
up hill! The answer is, of course, that the centrifugal force of the
Earth's spin impels it to flow that way. Similarly, I am sure now that
we will find that Venus has a vast belt of water about the middle, and
to the north and south there will be two great caps of dry land. We are
on the northern cap.

"We have the microphone turned way down. Let's step up the power a bit
and see if there are any sounds outside," said Arcot and walked over to
the power control switch. An instant later a low hum came from the
loudspeaker. There was a light breeze blowing. In the distance, forming
a dull background for the hum, there came a low rumbling that seemed
punctuated now and then by a greater sound.

"Must be a long way off," said Arcot, a puzzled frown on his face.
"Swing the ship around so we can see in what direction the sound is
loudest," he suggested.

Slowly Morey swung the ship around on its vertical axis. Without a
doubt, something off in the direction of the hills was making a
considerable noise.

"Arcot, if that's a fight between two animals--two of those giant
animals that you said might be here--I don't care to get near them!"
Fuller's narrowed eyes strove to penetrate the haze that screened the
low hills in the blue distance.

The microphone was shut off while the _Solarite_ shot swiftly forward
toward the source of the sound. Quickly the hills grew, the blue
mistiness disappearing, and the jagged mounds revealing themselves as
bleak harsh rock. As they drew nearer they saw beyond the hills,
intermittent flashes of brilliant light, heard shattering blasts of
sound.

"A thunderstorm!" Wade began, but Arcot interrupted.

"Not so fast, Wade--Fuller's animal _is_ there--the only animal in all
creation that can make a noise like that! Look through the
telescope--see those dots wheeling about there above the flashing
lights? The only animal that can make that racket is man! There are men
over there--and they aren't in a playful mood! Turn on the invisibility
while we can, Morey--and let's get nearer!"

"Look out--here we go!" Morey began to close a tiny switch set in one
side of the instrument panel--then, before the relay below could move,
he had flipped it back.

"Here, you take it, Arcot--you always think about two steps ahead of
me--you're quicker and know the machine better anyway."

Quickly the two men exchanged places.

"I don't know about that, Morey," said a voice from vacancy, for Arcot
had at once thrown the ship into invisibility. "The longer we're here,
the more mistakes I see we made in our calculations. I see what put me
off so badly on my estimate of the intelligence of life found here! The
sun gives it a double dose of heat--but also a double dose of other
radiations--some of which evidently speed up evolution. Anyway, we may
be able to find friends here more quickly if we aid one side or the
other in the very lively battle going on there. Before we go any
further, what's our decision?"

"I think it is a fine idea," said Fuller. "But which side are we to
aid--and what are the sides? We haven't even seen them yet. Let's go
nearer and take a good look."

"Yes--but are we going to join either side after looking?"

"Oh, that's unanimous!" said Wade, excitedly.

The invisible ship darted forward. They sped past the barrier of low
hills, and were again high above a broad plain. With a startled gasp,
Arcot cut their speed. There, floating high in the air, above a
magnificent city, was a machine such as no man had ever before seen! It
was a titanic airplane--monstrous, gargantuan, and every other word that
denoted immensity. Fully three-quarters of a mile the huge metal wings
stretched out in the dull light of the cloudy Venerian day; a machine
that seemed to dwarf even the vast city beneath it. The roar of its
mighty propellers was a rumbling thunder to the men in the _Solarite_.
From it came the flashing bursts of flame.

On closer inspection, the watchers saw what seemed to be a swarm of tiny
gnats flying about the mighty plane. They appeared to be attacking the
giant as vainly as gnats might attack an eagle, for they could not
damage the giant machine. The flashing bombs burst in blasts of yellow
flame as harmlessly as so many firecrackers.

All that mighty plane was covered with heavy metal plates, fully ten
inches thick, and of metal so tough that when the powerful bombs hit it
they made no impression, though they blasted tremendous craters in the
soil below. From it poured a steady stream of bombs that burst with a
great flash of heat and light, and in an instant the tiny planes they
struck streaked down as incandescent masses of metal.

Yet the giant seemed unable to approach the city--or was it defending
it? No, for it was from the city that the vainly courageous little ships
poured out. But certainly it was not these ships that kept the titanic
battleship of the air at bay!

Tensely the men watched the uneven conflict. The rain of bombs
continued, though all fell short of the city. But slowly around the
metropolis there appeared an area of flaring, molten lava, and steadily
this moved toward the beautiful buildings. Suddenly the battleship
turned toward the city and made a short dash inward on its circling
path. As though awaiting this maneuver, a battery of hissing, flaming
swords of white light flashed upward, a few hundred feet from the ring
of molten rock. As the titanic plane rolled, side-slipped out of the
way, they passed, harmlessly, barely missing a monstrous wing.

"Which?" Arcot demanded. "I say the city. No one should destroy anything
so magnificent."

Not a dissenting voice was raised, so Arcot sent the _Solarite_ nearer.

"But what in the world can we do to that huge thing?" Fuller's voice
came eerily out of the emptiness. "It has perfect invulnerability
through size alone."

There was sudden silence among the Terrestrials as one of the tiny
planes darted forward and dove at full speed directly toward one of the
giant's propellers. There were fifty of these strung along each great
wing. If enough of them could be destroyed, the plane must crash. There
came a terrific crash--a flare of light--and splintered fragments of
flaming wreckage plummeted down. Yet the mighty blades continued
whirling as smoothly as ever!

What could the _Solarite_ do against the giant monoplane? Evidently
Arcot had a plan. Under his touch their machine darted high into the sky
above the great plane. There was a full mile between them when he
released the sustaining force of the _Solarite_ and let it drop,
straight toward the source of the battle--falling freely, ever more and
more rapidly. They were rushing at the mighty plane below at a pace that
made their hearts seem to pause--then suddenly Arcot cried out, "Hold
on--here we stop!"

They seemed a scant hundred feet from the broad metal wings of the
unsuspecting plane, when suddenly there was a tremendous jerk, and each
man felt himself pressed to the floor beneath a terrific weight that
made their backs crack with the load. Doggedly they fought to retain
their senses; the blackness receded.

Below them they saw only a mighty sea of roaring red flames--a hell of
blazing gas that roared like a score of bombs set off at once. The
_Solarite_ was sitting down on her rocket jets! All six of the rocket
tubes in the base of the ship had been opened wide, and streaming from
them in a furious blast of incandescent gas, the atomic hydrogen shot
out in a mighty column of gas at 3500 degrees centigrade. Where the gas
touched it, the great plane flared to incandescence; and in an
immeasurable interval the fall of the _Solarite_ ended, and it rebounded
high into the air. Arcot, struggling against the weight of six
gravities, pulled shut the little control that had sent those mighty
torches blasting out. An instant later they sped away lest the plane
shoot toward the gas columns.

From a safe distance they looked back at their work. No longer was the
mighty plane unscathed, invulnerable, for now in its top gaped six great
craters of incandescent metal that almost touched and coalesced. The
great plane itself reeled, staggering, plunging downward; but long
before it reached the hard soil below, it was brought into level flight,
and despite many dead engines, it circled and fled toward the south. The
horde of small planes followed, dropping a rain of bombs into the
glowing pits in the ship, releasing their fury in its interior. In
moments the beings manning the marauder had to a large extent recovered
from the shock of the attack and were fighting back. In a moment--just
before the ship passed over the horizon and out of sight--the
Terrestrians saw the great props that had been idle, suddenly leap into
motion, and in an instant the giant had left its attackers
behind--fleeing from its invisible foe.

Under Arcot's guidance the ship from Earth, still invisible, returned to
the approximate spot where they had destroyed the invulnerability of the
Giant. Then suddenly, out of nothing, the _Solarite_ appeared. In an
instant a dozen of the tiny two-man planes darted toward it. Just that
they might recognize it, Arcot shot it up a bit higher with the aid of
the keel rockets at one-third power. The typical reddish flame of atomic
hydrogen, he knew, would be instantaneously recognizable.

Little these planes were, but shaped like darts, and swifter than any
plane of Earth. They shot along at 1000 miles an hour readily, as Arcot
soon found out. It was not a minute before they had formed a long line
that circled the _Solarite_ at minimum speed, then started off in the
direction of the city. On impulse Arcot followed after them, and
instantly the planes increased their velocity, swiftly reaching 1000
miles per hour.

The city they were approaching was an inspiring sight. Mighty towers
swept graceful lines a half mile in the air, their brightly colored
walls gleaming in rainbow hues, giving the entire city the aspect of a
gigantic jewel--a single architectural unit. Here was symmetry and
order, with every unit in the city built around the gigantic central
edifice that rose, a tremendous tower of black and gold, a full half
mile in the air.

The outer parts of the city were evidently the residential districts,
the low buildings and the wide streets with the little green lawns
showing the care of the individual owner. Then came the apartment houses
and the small stores; these rose in gentle slopes, higher and higher,
merging at last with the mighty central pinnacle of beauty. The city was
designed as a whole, not in a multitude of individually beautiful, but
inharmonious units, like some wild mixture of melodies, each in itself
beautiful, but mutually discordant.




V


The Terrestrians followed their escort high above these great buildings,
heading toward the great central tower. In a moment they were above it,
and in perfect order the ships of the Venerians shot down to land
smoothly, but at high speed. On the roof of the building they slowed
with startling rapidity, held back by electromagnets under the top
dressing of the roof landing, as Arcot learned later.

"We can't land on that--this thing weighs too much--we'd probably sink
right through it! The street looks wide enough for us to land there."
Arcot maneuvered the _Solarite_ over the edge of the roof, and dropped
it swiftly down the half mile to the ground below. Just above the
street, he leveled off, and descended slowly, giving the hurrying crowds
plenty of time to get from beneath it.

Landing finally, he looked curiously at the mass of Venerians who had
gathered in the busy street, coming out of buildings where they
evidently had sought shelter during the raid. The crowd grew rapidly as
the Terrestrians watched them--people of a new world.

"Why," exclaimed Fuller in startled surprise, "they look almost like
us!"

"Why not?" laughed Arcot. "Is there any particular reason why they
shouldn't look like us? Venus and Earth are very nearly the same size,
and are planets of the same parent sun. Physical conditions here appear
to be very similar to conditions back home, and if there's anything to
Svend Arrehenius' theory of life spores being sent from world to world
by sunlight, there's no reason why humanoid races cannot be found
throughout the universe. On worlds, that is, suitable for the
development of such life forms."

"Look at the size of 'em," Fuller commented.

Their size was certainly worth noting, for in all that crowd only the
obviously young were less than six feet tall. The average seemed to be
seven feet--well-built men and women with unusually large chests, who
would have seemed very human indeed, but for a ghastly, death-like blue
tinge to their skin. Even their lips were as bright a blue as man's lips
are red. The teeth seemed to be as white as any human's, but their
mouths were blue.

"They look as if they'd all been eating blueberries!" laughed Wade. "I
wonder what makes their blood blue? I've heard of blue-blooded families,
but these are the first I've ever seen!"

"I think I can answer that," said Morey slowly. "It seems odd to us--but
those people evidently have their blood based on hemocyanin. In us, the
oxygen is carried to the tissues, and the carbon dioxide carried away by
an iron compound, hemoglobin, but in many animals of Earth, the same
function is performed by a copper compound, hemocyanin, which is an
intense blue. I am sure that that is the explanation for these strange
people. By the way, did you notice their hands?"

"Yes, I had. They strike me as having one too many fingers--look
there--that fellow is pointing--why--his hand hasn't too many fingers,
but too many thumbs! He has one on each side of his palm! Say, that
would be handy in placing nuts and bolts, and such fine work, wouldn't
it?"

Suddenly a lane opened in the crowd, and from the great black and gold
building there came a file of men in tight-fitting green uniforms; a
file of seven-foot giants. Obviously they were soldiers of some
particular branch, for in the crowd there were a number of men dressed
in similar uniforms of deep blue.

"I think they want one or more of us to accompany them," Arcot said.
"Let's flip a coin to decide who goes--two better stay here, and two go.
If we don't come back inside of a reasonable period of time, one of you
might start making inquiries; the other can send a message to Earth, and
get out of harm's way till help can come. I imagine these people are
friendly now, however--else I wouldn't go."

The leader of the troop stepped up to the door of the _Solarite_, and
coming to what was obviously a position of attention, put his left hand
over his right breast in an equally obvious salute, and waited.

The coin was flipped with due ceremony--it would decide which of them
were to have the distinction of being the first Terrestrians to set foot
on Venus. Arcot and Morey won, and they quickly put on the loose-fitting
ventilated cooling suits that they might live comfortably in the hot air
outside--for the thermometer registered 150°!

The two men quickly walked over to the airlock, entered, closed it
behind them, and opened the outer door. There was a slight rush of air,
as the pressure outside was a bit lower than that inside. There was a
singing in their ears, and they had to swallow several times to equalize
the pressure.

The guards at once fell into a double row on either side of them, and
the young officer strode ahead. He himself had curbed his curiosity
after the single startled glance he had given these strange men. Only
their hands were visible, for the cooling suits covered them almost
completely, but the strange pink color must indeed have been startling
to the eyes; also their dwarf stature, and the strange suits they wore.
The men of his little troop, however, as well as the people in the crowd
about them, were not so disinterested. They were looking in eager
amazement at these men who had just saved their city, these strange
small men with their queer pink skin. And most surprising of all,
perhaps, the inner thumb was missing from each hand!

But soon they had passed beyond the sight of the crowd, which was held
in check by a handful of the deep blue uniformed men.

"Those fellows would never hold such a Terrestrial crowd back if
visitors from another planet landed!" remarked Morey wonderingly.

"How do they know we are visitors from another planet?" Arcot objected.
"We suddenly appeared out of nowhere--they don't even know our direction
of approach. We might be some strange race of Venerians as far as they
know."

They walked briskly up to the massive gold and black entrance, and
passed through the great doors that seemed made of solid copper, painted
with some clear coating that kept the metal lustrous, the rich color
shining magnificently. They stood open wide now, as indeed they always
were. Even the giant Venerians were dwarfed by these mighty doors as
they passed through into an equally vast hall, a tremendous room that
must have filled all the front half of the ground floor of the gigantic
building, a hall of graceful columns that hid the great supporting
members. The stone, they knew, must serve the Venerians as marble serves
us, but it was a far more handsome stone. It was a rich green, like the
green of thick, heavy grass in summer when the rain is plentiful. The
color was very pleasing to the eye, and restful too. There was a
checker-board floor of this green stone, alternated with another, a
stone of intense blue. They were hard, and the colors made a very
striking pattern, pleasingly different from what they had been
accustomed to, but common to Venus, as they later learned.

At last the party had crossed the great hall, and stopped beside a large
doorway. The officer halted for a moment, and gestured toward two of his
men, who remained, while the others walked quickly away. The diminished
party stepped through the doorway into a small room whose walls were
lined with copper, and an instant later, as the officer pushed a small
button, there was a low hiss of escaping air, and a copper grating
sprang quickly up across the opening of the elevator. He touched another
button, and there was the familiar sinking feeling as the car rose, a
low hum seeming to come from its base.

The elevator rose swiftly through a very considerable distance--up--up,
endlessly.

"They must have some wonderfully strong cables here on Venus!" Morey
exclaimed. "The engineers of Terrestrial buildings have been wondering
for some time how to get around the difficulty of shifting elevators.
The idea of changing cars doesn't appeal to me, either--but we must have
risen a long way!"

"I should say so--I wonder how they do it. We've been rising for a
minute and a half at a very fair clip--there we are; end of the line--I
want to look at this car!" Arcot stepped over to the control board,
looked at it closely, then stepped out and peered down between the car
and the shaft as the copper grating fell, simultaneously pulling down
with it the door that had blocked off the hallway.

"Come here, Morey--simple system at that! It would be so, of course.
Look--they have tracks, and a regular trolley system, with cog rails
alongside, and the car just winds itself up! They have a motor
underneath, I'll bet, and just run it up in that way. They have never
done that on Earth because of the cost of running the car up without too
much power. I think I see the solution--the car has electro-dynamical
brakes, and descending, just slows itself down by pumping power into the
line to haul some other car up. This is a mighty clever scheme!"

As Arcot straightened, the officer beckoned to him to follow, and
started down the long corridor which was lined on either side with large
doorways, much like a very exotic earthly office building. Passing
through a long series of branching corridors they at last reached one
that terminated in a large office, into which the young officer led
them. Snapping to attention, he spoke briefly and rapidly, saluted and
retired with his two men.

The man before whom the Terrestrians stood was a tall, kindly-faced old
gentleman. His straight black hair was tinged with bluish gray, and the
kindly face bore the lines of age, but the smiling eyes, and the air of
sincere interest gave his countenance an amazingly youthful air. It was
warm and friendly despite its disconcerting blueness. He looked
curiously, questioningly at the two men before him, looked at their
hands, his eyes widening in surprise; then he stepped quickly forward,
and extended his hand, at the same time looking toward Arcot.

Smiling, Arcot extended his own. The Venerian grasped it--then with an
exclamation on the part of each, they mutually released each other,
Arcot feeling an uncomfortable sensation of heat, just as the Venerian
felt a flash of intense cold! Each stared from his hand to the hand of
the other in surprise, then a smile curved the blue lips of the Venerian
as he very emphatically put his hand at his side. Arcot smiled in turn,
and said to Morey in an animated tone:

"They have a body temperature of at least 170° Fahrenheit. It would
naturally be above room temperature, which is 150° here, so that they
are most unpleasantly hot to us. Marvelous how nature adapts herself to
her surroundings!" He chuckled. "I hope these fellows don't have fevers.
They'd be apt to boil over!"

The Venerian had picked up a small rectangle of black material, smooth
and solid. He drew quickly upon it with what appeared to be a pencil of
copper. In a moment he handed the tablet to Arcot, who reached out for
it, then changed his mind, and motioned that he didn't want to burn his
fingers. The old Venerian held it where Arcot could see it.

"Why, Morey, look here--I didn't think they had developed astronomy to
any degree, because of the constant clouds, but look at this. He has a
nice little map of the solar system, with Mercury, Venus, Earth, the
Moon, Mars, and all the rest on it. He has drawn in several of the
satellites of Jupiter and of Saturn too."

The Venerian pointed to Mars and looked inquisitively at them. Arcot
shook his head and pointed quickly to Earth. The Venetian seemed a bit
surprised at this, then thought a moment and nodded in satisfaction. He
looked at Arcot intently. Then to the latter's amazement, there seemed
to form in his mind a thought--at first vague, then quickly taking
definite form.

"Man of Earth," it seemed to say, "we thank you--you have saved our
nation. We want to thank you for your quick response to our signals. We
had not thought that you could answer us so soon." The Venerian seemed
to relax as the message was finished. It obviously had required great
mental effort.

Arcot looked steadily into his eyes now, and tried to concentrate on a
message--on a series of ideas. To him, trained though he was in deep
concentration on one idea, the process of visualizing a series of ideas
was new, and very difficult. But he soon saw that he was making some
progress.

"We came in response to no signals--exploration only--we saw the
battle--and aided because your city seemed doomed, and because it seemed
too beautiful to be destroyed."

"What's it all about, Arcot?" asked Morey wonderingly, as he watched
them staring at each other.

"Mental telepathy," Arcot answered briefly. "I'm terribly thick from his
point of view, but I just learned that they sent signals to Earth--why,
I haven't learned--but I'm making progress. If I don't crack under the
strain, I'll find out sooner or later--so wait and see." He turned again
to the Venerian.

The latter was frowning at him rather dubiously. With sudden decision he
turned to his desk, and pulled down a small lever. Then again he looked
intently at Arcot.

"Come with me--the strain of this conversation is too great--I see you
do not have thought transference on your world."

"Come along, Morey--we're going somewhere. He says this thought
transference is too much for us. I wonder what he is going to do?"

Out into the maze of halls they went again, now led by the kindly
seven-foot Venerian. After walking through a long series of halls, they
reached a large auditorium, where already there had gathered in the
semi-circle of seats a hundred or so of the tall, blue-tinged Venerians.
Before them, on a low platform, were two large, deeply-cushioned chairs.
To these chairs the two Terrestrians were led.

"We will try to teach you our language telepathically. We can give you
the ideas--you must learn the pronunciation, but this will be very much
quicker. Seat yourselves in these chairs and relax."

The chairs had been designed for the seven-footers. These men were six
feet and six feet six, respectively, yet it seemed to them, as they sank
into the cushions, that never had they felt such comfortable chairs.
They were designed to put every muscle and every nerve at rest.
Luxuriously, almost in spite of themselves, they relaxed.

Dimly Arcot felt a wave of sleepiness sweep over him; he yawned
prodigiously. There was no conscious awareness of his sinking into a
deep slumber. It seemed that suddenly visions began to fill his
mind--visions that developed with a returning consciousness--up from the
dark, into a dream world. He saw a mighty fleet whose individual planes
were a mile long, with three-quarters of a mile wingspread--titanic
monoplanes, whose droning thunder seemed to roar through all space. Then
suddenly they were above him, and from each there spurted a great stream
of dazzling brilliance, an intense glow that reached down, and touched
the city. An awful concussion blasted his ears. All the world about him
erupted in unimaginable brilliance; then darkness fell.

Another vision filled his mind--a vision of the same fleet hanging over
a giant crater of molten rock, a crater that gaped angrily in a plain
beside low green hills--a crater that had been a city. The giants of the
air circled, turned, and sped over the horizon. Again he was with
them--and again he saw a great city fuse in a blazing flash of blinding
light--again and yet again--until around all that world he saw smoking
ruins of great cities, now blasted crimson craters in a world of fearful
desolation.

The destroyers rode up, up, up--out of the clouds--and he was with them.
Out beyond the swirling mists, where the cold of space seemed to reach
in at them, and the roaring of the mighty propellers was a thin
whine--then suddenly that was gone, and from the tail of each of the
titanic machines there burst a great stream of light, a blazing column
that roared back, and lit all space for miles around--rocket jets that
sent them swiftly across space!

He saw them approaching another world, a world that shone a dull red,
but he saw the markings and knew that it was Earth, not Mars. The great
planes began falling now--falling at an awful speed into the upper air
of the planet, and in an instant the rocket flares were gone, fading and
dying in the dense air. Again there came the roar of the mighty
propellers. Then swiftly the fleet of giants swooped down, lower and
lower. He became aware of its destination--a spot he knew must be New
York--but a strangely distorted New York--a Venerian city, where New
York should have been. And again, the bombs rained down. In an instant
the gigantic city was a smoking ruin.

The visions faded, and slowly he opened his eyes, looked about him. He
was still in the room of the circle of chairs--he was still on
Venus--then with sudden shock, understanding came. He knew the meaning
of these visions--the meaning of that strangely distorted New York, of
that red earth. It meant that this was what the Venerians believed was
to happen! They were trying to show him the plans of the owners and
builders of those gigantic ships! The New York he had seen was New York
as these men imagined it.

Startled, confused, his forehead furrowed, he rose unsteadily to his
feet. His head seemed whirling in the throes of a terrific headache. The
men about him were looking anxiously at him. He glanced toward Morey. He
was sleeping deeply in the seat, his features now and again reflecting
his sensations. It was his turn to learn this new language and see the
visions.

The old Venerian who had brought them there walked up to Arcot and spoke
to him in a softly musical language, a language that was sibilant and
predominated in liquid sounds; there were no gutturals, no nasals; it
was a more musical language than Earth men had ever before heard, and
now Arcot started in surprise, for he understood it perfectly; the
language was as familiar as English.

"We have taught you our language as quickly as possible--you may have a
headache, but you must know what we know as soon as possible. It may
well be that the fate of two worlds hangs on your actions. These men
have concentrated on you and taught you very rapidly with the massed
power of their minds, giving you visions of what we know to be in
preparation. You must get back to your wonderful ship as quickly as
possible; and yet you must know what has happened here on our world in
the last few years, as well as what happened twenty centuries ago.

"Come with me to my office, and we will talk. When your friend has also
learned, you may tell him."

Quickly Arcot followed the Venerian down the long corridors of the
building. The few people they met seemed intent on their own business,
paying little attention to them.

At last they seated themselves in the office where Arcot had first met
his escort; and there he listened to a new history--the history of
another planet.

"My name is Tonlos," the old man said. "I am a leader of my
people--though my title and position are unimportant. To explain would
entail a prolonged discussion of our social structure, and there is no
time for that. Later, perhaps--but now to our history.

"Twenty centuries ago," Tonlos continued, "there were two great rival
nations on this planet. The planet Turo is naturally divided so that
there would be a tendency toward such division. There are two enormous
belts of land around the globe, one running from about 20 degrees north
of the equator to about 80 degrees north. This is my country, Lanor. To
the south there is a similar great belt of land, of almost identical
size, Kaxor. These two nations have existed for many thousands of our
years.

"Two thousand years ago a great crisis arose in the affairs of the
world--a great war was in process of starting--but a Lanorian developed
a weapon that made it impossible for the Kaxorians to win--and war was
averted. The feeling was so strong, however, that laws were passed which
stopped all intercourse between the two nations for these thousands of
years. By devious ways we've learned that Kaxor has concentrated on the
study of physics, perhaps in hopes of finding a weapon with which they
could threaten us once more. Lanor has studied the secrets of the human
mind and body. We have no disease here any longer; we have no insanity.
We are students of chemistry, but physics has been neglected to a great
extent. Recently, however, we have again taken up this science, since it
alone of the main sciences had not received our study. Only twenty-five
years have been spent on these researches, and in that short time we
cannot hope to do what the Kaxorians have done in two thousand.

"The secret of the heat ray, the weapon that prevented the last war, had
been almost forgotten. It required diligent research to bring it to life
again, for it is a very inefficient machine--or was. Of late, however,
we have been able to improve it, and now it is used in commerce to smelt
our ores. It was this alone that allowed this city to put up the slight
resistance that we did. We were surely doomed. This is the capital of
Lanor, Sonor. We--and the nation--would have fallen but for you.

"We have had some warning that this was coming. We have spies in Kaxor
now, for we learned of their intentions when they flew the first of
their giant planes over one of our cities and dropped a bomb! We have
been trying, since we discovered the awful scope of their plans, to send
you a warning if you could not help us. That you should come here at
this particular time is almost beyond belief--a practically impossible
coincidence--but perhaps there is more than coincidence behind it? Who
knows?" He paused briefly; went on with a heavy sigh: "Since you drove
that plane away, we can expect a new raid at any moment, and we must be
prepared. Is there any way you can signal your planet?"

"Yes--we can signal easily," Arcot answered; he struggled with the newly
acquired language. "I do not know the word in your tongue--it may be
that you do not have it--radio we call it--it is akin to light, but of
vastly longer wavelength. Produced electrically, it can be directed like
light and sent in a beam by means of a reflection. It can penetrate all
substances except metals, and can leak around them, if it be not
directional. With it I can talk readily with the men of Earth, and this
very night I will."

Arcot paused, frowning thoughtfully, then continued, "I know there's
definite need for haste, but we can't do anything until Morey has
received the knowledge you've given me. While we're waiting here, I
might just as well learn all I can about your planet. The more I know,
the more intelligently I'll be able to plan for our defense."

In the conversation which followed, Arcot gained a general knowledge of
the physical makeup of Venus. He learned that iron was an exceedingly
rare element on the planet, while platinum was relatively plentiful.
Gold, though readily available, was considered a nuisance, since it was
of no practical value due to its softness, excessive weight and its
affinity for many catalysts. Most of the other metallic elements were
present in quantities approximating those of Earth, except for an
element called "morlus". When Tonlos mentioned this, Arcot said:

"Morlus--I have the word in your language--but I do not know the
element. What is it?"

"Why--here is some!"

Tonlos handed Arcot a small block of metal that had been used as a
weight on a table in one corner of the room. It seemed fairly dense,
about as heavy as iron, but it had a remarkably bluish tint. Obviously,
it was the element that composed the wings of the airplane they had
seen that afternoon. Arcot examined it carefully, handicapped somewhat
by its heat. He picked up a small copper rod and tried to scratch it but
there was no noticeable effect.

"You cannot scratch it with copper," said Tonlos. "It is the second
hardest metal we know--it is not as hard as chromium, but far less
brittle. It is malleable, ductile, very very strong, very tough,
especially when alloyed with iron, but those alloys are used only in
very particular work because of iron's rarity."

Indicating the bluish block, Arcot said, "I'd like to identify this
element. May I take it back to the ship and test it?"

"You may, by all means. You will have considerable difficulty getting it
into solution, however. It is attacked only by boiling selenic acid
which, as you must know, dissolves platinum readily. The usual test for
the element is to so dissolve it, oxidize it to an acid, then test with
radium selenate, when a brilliant greenish blue salt is--"

"Test with radium selenate!" Arcot exclaimed. "Why, we have no radium
salts whatever on Earth that we could use for that purpose. Radium is
exceedingly rare!"

"Radium is by no means plentiful here," Tonlos replied, "but we seldom
have to test for morlus, and we have plenty of radium salts for that
purpose. We have never found any other use for radium--it is so active
that it combines with water just as sodium does; it is very soft--a
useless metal, and dangerous to handle. Our chemists have never been
able to understand it--it is always in some kind of reaction no matter
what they do, and still it gives off that very light gas, helium, and a
heavy gas, niton, and an unaccountable amount of heat."

"Your world is vastly different from ours," Arcot commented. He told
Tonlos of the different metals of Earth, the non-metals, and their
occurrence. But try as he would, he could not place the metal Tonlos had
given him.

Morey's arrival interrupted their discussion. He looked very tired, and
very serious. His head ached from his unwonted mental strain, just as
Arcot's had. Briefly Arcot told him what he had learned, concluding with
a question as to why Morey thought the two planets, both members of the
same solar family, should be so different.

"I have an idea," said Morey slowly, "and it doesn't seem _too_ wacky.
As you know, by means of solar photography, astronomers have mapped the
sun, charting the location of the different elements. We've seen
hydrogen, oxygen, silicon and others, and as the sun aged, the elements
must have been mixed up more and more thoroughly. Yet we have seen the
vast areas of single elements. Some of those areas are so vast that they
could easily be the source of an entire world! I wonder if it is not
possible that Earth was thrown off from some deposit rich in iron,
aluminum and calcium, and poor in gold, radium and those other
metals--and particularly poor in one element. We have located in the sun
the spectrum of an element we have named coronium--and I think you have
a specimen of coronium in your hand there! I'd say Venus came from a
coronium-rich region!"

The discussion ended there, for already the light outside had deepened
to a murky twilight. The Terrestrians were led quickly down to the
elevator, which dropped them rapidly to the ground. There was still a
large crowd about the _Solarite_, but the way was quickly cleared for
them. As the men passed through the crowd, a peculiar sensation struck
them very forcibly. It seemed that everyone in the crowd was wishing
them the greatest success--the best of good things in every wish.

"The ultimate in applause! Morey, I'll swear we just received a silent
cheer!" exclaimed Arcot, as they stood inside the airlock of the ship
once more. It seemed home to them now! In a moment they had taken off
the uncomfortable ventilating suits and stepped once more into the room
where Wade and Fuller awaited them.

"Say--what were you fellows doing?" Wade demanded. "We were actually
getting ready to do some inquiring about your health!"

"I know we were gone a long time--but when you hear the reason you'll
agree it was worth it. See if you can raise Earth on the radio, Morey,
will you, while I tell these fellows what happened? If you succeed, tell
them to call in Dad and your father, and to have a couple of tape
recorders on the job. We'll want a record of what I have to send. Say
that we'll call back in an hour." Then, while Morey was busy down in the
power room sending the signals out across the forty million miles of
space that separated them from their home planet, Arcot told Wade and
Fuller what they had learned.

Morey finally succeeded in getting his message through, and returned to
say that they would be waiting in one hour. He had had to wait eight
minutes after sending his message to get any answer, however, due to
time required for radio waves to make the two-way trip.

"Fuller," Arcot said, "as chef, suppose you see what you can concoct
while Wade and I start on this piece of coronium and see what there is
to learn."

At the supper table Wade and Arcot reported to the others the curious
constants they had discovered for coronium. It was not attacked by any
acid except boiling selenic acid, since it formed a tremendous number of
insoluble salts. Even the nitrate violated the long-held rule that "all
nitrates are soluble"--it wouldn't dissolve. Yet it was chemically more
active than gold.

But its physical constants were the most surprising. It melted at 2800°
centigrade, a very high melting point indeed. Very few metals are solid
at that temperature. But the tensile strength test made with a standard
bar they finally turned out by means of a carbaloy tool, gave a reading
of more than one million, three hundred thousand pounds per square inch!
It was far stronger than iron--stronger than tungsten, the strongest
metal heretofore known. It was twice as strong as the Earth's strongest
metal!

Fuller whistled in awe. "No wonder they can make a plane like that when
they have such a metal to work with." The designing engineer had visions
of a machine after his own heart--one in which half the weight was
_not_ employed in holding it together!

It was a little later that they got communication through to Earth, and
the men went to the power room. The television screen was struggling to
form a clear image despite the handicap of forty million miles of space.
In a moment it had cleared, though, and they saw the face of Dr. Arcot.
He showed plainly that he was worried about the startling news that had
reached him already, sketchy though it was. After brief though warm
greetings, his son rapidly outlined to him the full extent of their
discoveries, and the force that Earth would have to meet.

"Dad, these Kaxorians have planes capable of far more than a thousand
miles an hour in the air. For some reason the apparatus they use to
propel them in space is inoperative in air, but their propellers will
drive them forward faster than any plane Earth ever saw. You must start
at once on a fleet of these molecular motion planes--and a lot of the
gas Wade developed--you know how to make it--the animation suspending
gas. They don't have it--and I believe it will be useful. I'll try to
develop some new weapons here. If either of us makes any progress along
new lines--we'll report to the other. I must stop now--a Lanorian
delegation is coming." After a few words of farewell, Arcot severed
connections with the Earth and arose to await the arrival of the
visitors.

Since the return of the Terrestrians to the _Solarite_, a great crowd of
Venerians had gathered around it, awaiting a glimpse of the men, for the
news had spread that this ship had come from Earth. Now, the crowd had
divided, and a group of men was approaching, clothed in great heavy
coats that seemed warm enough to wear in Terrestrial arctic regions!

"Why--Arcot--what's the idea of the winter regalia?" asked Fuller in
surprise.

"Think a moment--they are going to visit a place whose temperature is
seventy degrees colder than their room temperature. In the bargain,
Venus never has any seasonal change of temperature, and a heavy bank of
clouds that eternally cover the planet keeps the temperature as constant
as a thermocouple arrangement could. The slight change from day to night
is only appreciable by the nightly rains--see--the crowd is beginning to
break up now. It's night already, and there is a heavy dew settling.
Soon it will be rain, and the great amount of moisture in the air will
supply enough heat, in condensing, to prevent a temperature drop of more
than two or three degrees. These men are not used to changes in
temperature as we are and hence they must protect themselves far more
fully."

Three figures now entered the airlock of the _Solarite_, and muffled in
heavy garments as they were, large under any conditions, they had to
come through one at a time.

Much that Arcot showed them was totally new to them. Much he could not
explain to them at all, for their physics had not yet reached that
stage.

But there was one thing he could show them, and he did. There were no
samples of the liquids he wanted, but their chemistry was developed to a
point that permitted the communication of the necessary data and Arcot
told them the formula of Wade's gas. Its ability to penetrate any
material at ordinary temperatures, combined with its anesthetic
properties, gave it obvious advantages as a weapon for rendering the
opposing forces defenseless.

Since it was able to penetrate all substances, there was no means of
storing it. Hence it was made in the form of two liquids which reacted
spontaneously and produced the gas, which was then projected to the spot
where needed.

Arcot asked now that the Venerian chemists make him a supply of these
two liquids; and they promptly agreed. He felt he would have a fighting
chance in combatting the enemy if he could but capture one of their
flying forts. It seemed a strange task! Capturing so huge a machine with
only the tiny _Solarite_--but Arcot felt there was a good possibility of
his doing it if he but had a supply of that gas.

There was one difficulty--one step in the synthesis required a
considerable quantity of chlorine. Since chlorine was rare on Venus,
the men were forced to sacrifice most of their salt supply; but this
chlorine so generated could be used over and over again.

It was quite late when the Venerians left, to go again into the scalding
hot rain, rain that seemed to them to be a cold drizzle. After they had
gone, the Terrestrians turned in for the night, leaving a telephone
connection with the armed guard outside.

       *       *       *       *       *

The dull light of the Venerian day was filtering in through the windows
the next morning when the Terrestrians awoke. It was eight o'clock, New
York time, but Sonor was working on a twenty-three hour day. It happened
that Sonor and New York had been in opposition at midnight two nights
ago, which meant that it was now ten o'clock Sonorian time. The result
was that Arcot left the car to speak to the officer in charge of the
guard about the ship.

"We need some pure water--water free of copper salts. I think it would
be best if you can get me some water that has been distilled. That is,
for drinking. Also we need about two tons of water of any kind--the
ship's tanks need recharging. I'd like about a ton of the drinking
water." Arcot had to translate the Terrestrian measures into the
corresponding Venerian terms, of course, but still the officer seemed
puzzled. Such a large amount of water would create a real problem in
transportation. After apparently conferring by telepathic means with his
superiors, the officer asked if the _Solarite_ could be moved to some
more accessible place.

Arcot agreed to have it moved to a spot just outside the city, where the
water could be procured directly from a stream. The drinking water would
be ready when he returned to the city.

The _Solarite_ was moved to the bank of the little river and the
electrolysis apparatus was set up beside it. During the previous day,
and ever since they had landed on Venus, all their power had been coming
from the storage cells, but now that the electrolysis apparatus was to
establish such a heavy and constant drain, Arcot started the generator,
to both charge the cells, and to do the work needed.

Throughout the day there could be heard the steady hum of the generator,
and the throb-throb-throb of the oxygen pump, as the gas was pumped into
the huge tanks. The apparatus they were using produced the gas very
rapidly, but it was near nightfall before the huge tanks had again been
filled. Even then there was a bit more room for the atomic hydrogen that
was simultaneously formed, although twice as much hydrogen as oxygen was
produced. Its task completed, the _Solarite_ rose again and sped toward
the distant city.

A soft red glow filled the sky now, for even through the miles of clouds
the intense sun was able to force some direct rays, and all the city was
lighted with that warm radiance. The floodlights had not yet been turned
on, but the great buildings looming high in the ruddy light were
wonderfully impressive, the effect being heightened by the planned
construction, for there were no individual spires, only a single mass
that grew from the ground to tower high in the air, like some man-made
mountain.

Back at the Capital the _Solarite_ again settled into the broad avenue
that had been cut off to traffic now, and allotted to it as its resting
place. Tonlos met them shortly after they had settled into place, and
with him were five men, each carrying two large bottles.

"Ah-co," as Tonlos pronounced the Terrestrian name, "we have not been
able to make very much of the materials needed for your gas, but before
we made any very great amount, we tried it out on an animal, whose blood
structure is the same as ours, and found it had the same effect, but
that in our case the iodide of potassium is not as effective in
awakening the victim as is the sorlus. I do not know whether you have
tried that on Terrestrial animals or not. Luckily sorlus is the most
plentiful of the halogen groups; we have far more of it than of
chlorine, bromine or iodine."

"Sorlus? I do not know of it--it must be one of the other elements that
we do not have on Earth. What are its properties?"

"It, too, is much like iodine, but heavier. It is a black solid melting
at 570 degrees; it is a metallic looking element, will conduct
electricity somewhat, oxidizes in air to form an acidic oxide, and forms
strong oxygen acids. It is far less active than iodine, except toward
oxygen. It is very slightly soluble in water. It does not react readily
with hydrogen, and the acid where formed is not as strong as HI."

"I have seen so many new things here, I wonder if it may not be the
element that precedes niton. Is it heavier than that?"

"No," replied Tonlos; "it is just lighter than that element you call
niton. I think you have none of it."

"Then," said Arcot, "it must be the next member of the halogen series,
Morey. I'll bet they have a number of those heavier elements."

The gas was loaded aboard the _Solarite_ that evening, and when Wade saw
the quantity that they had said was "rather disappointingly small" he
laughed heartily.

"Small! They don't know what that gas will do! There's enough stuff
there to gas this whole city. Why, with that, we can bring down any
ship! But tell them to go on making it, for we can use it on the other
ships."

Again that night they spoke with Earth, and Morey, Senior, told them
that work was already under way on a hundred small ships. They were
using all their own ships already, while the Government got ready to act
on the idea of danger. It had been difficult to convince them that
someone on Venus was getting ready to send a force to Earth to destroy
them; but the weight of their scientific reputation had turned the
trick. The ships now under construction would be ready in three weeks.
They would be unable to go into space, but they would be very fast, and
capable of carrying large tanks of the gas-producing chemicals.

It was near midnight, Venerian time, when they turned in. The following
day they planned to start for the Kaxorian construction camp. They had
learned from Tonlos that there were but five of the giant planes
completed now, but there were fifteen more under construction, to make
up the fleet of twenty that was to attack Earth. These fifteen others
would be ready in a week--or less. When they were ready, the _Solarite_
would stand small chance. They must capture one of the giants and learn
its secrets, and then, if possible, with the weapons and knowledge of
two worlds, defeat them. A large order!

Their opportunity came sooner than they had hoped for--or wanted. It was
about three o'clock in the morning when the telephone warning hummed
loudly through the ship. Arcot answered.

Far to the east and south of them the line of scout planes that
patrolled all the borders of Lanor had been broken. Instantaneously, it
seemed, out of the dark, its lights obscured, the mighty Kaxorian craft
had come, striking a tiny scout plane head on, destroying it utterly
before the scout had a chance to turn from the path of the titanic ship.
But even as the plane spun downward, the pilot had managed to release a
magnesium flare, a blindingly brilliant light that floated down on a
parachute, and in the blaze of the white light it gave off, the other
scouts at a few miles distance had seen the mighty bulk of the Kaxorian
plane. At once they had dropped to the ground and then, by telephone
lines, had sent their report to far off Sonor.

In moments the interior of the _Solarite_ became a scene of swift
purposeful activity. All day the Terrestrians had been able to do so
little in preparation for the conflict they knew must come, the battle
for two worlds. They had wanted action, but they had no weapons except
their invisibility and the atomic hydrogen. It would not sink a plane.
It would only break open its armor, and they hoped, paralyze its crew.
And on this alone they must pin their hopes.




VI


Arcot lifted the _Solarite_ at once high into the air, and started
toward the point on the border, where the plane had been seen crossing.
In a short time Wade relieved him at the controls while he dressed.

They had been flying on in silence for about an hour, when suddenly Wade
made out in the distance the great bulk of the plane, against the dull
gray of the clouds, a mile or so above them. It seemed some monstrous
black bat flying there against the sky, but down to the sensitive
microphone on the side of the _Solarite_ came the drone of the hundred
mighty propellers as the great plane forged swiftly along.

Just how rapidly these giants moved, Arcot had not appreciated until he
attempted to overtake this one. It was going over a mile a second now--a
speed that demanded only that it move its own length in about
five-eights of a second! It made this tremendous speed by streamlining
and through sheer power.

The _Solarite_ hovered high above the dark ship at length, the roar of
the terrific air blast from its propellers below coming up to them as a
mighty wave of sound that made their own craft tremble! The hundred
gigantic propellers roaring below, however, would distribute their gas
perfectly.

"We're going invisible," Arcot exclaimed. "Look out!" There was a click
as the switch shut, and the _Solarite_ was as transparent as the air
above it. Arcot drove his ship swiftly, above and ahead of the mighty
colossus, then released the gas. There was a low hiss from the power
room, barely detectable despite the vacuum that shut them off from the
roar of the Kaxorian plane. The microphone had long since been
disconnected. Out of the gas vent streamed a cloud of purplish gas,
becoming faintly visible as it left the influence of the invisibility
apparatus, but only to those who knew where to look for it. The men in
that mighty plane could not see it as their machine bore down into the
little cloud of gas.

Tensely the Terrestrians waited. Moments--and the gigantic plane
wobbled! There was a sudden swerve that ended in a nose dive, straight
toward Venus seven miles below.

That the ship should crash into the ground below was not at all Arcot's
plan, and he was greatly relieved when it flattened its dive and started
to climb, its incalculable mass rapidly absorbing its kinetic energy.
Down from its seven mile height it glided, controlling itself perfectly
as Arcot released the last of the first four containers of the liquid
gas makers, putting to sleep the last man on the ship below.

In a long glide that carried it over many miles, the great ship
descended. It had sunk far, and gone smoothly, but now there loomed
ahead of it a range of low hills! It would certainly crash into the
rocky cliffs ahead! Nearer and nearer drew the barrier while Arcot and
the others watched with rigid attention. It might skim above those low
hills at that--just barely escaping.... The watchers cringed as head on,
at nearly two thousand miles an hour, the machine crashed into the
rocks. Arcot had snapped the loud speaker into the circuit once more,
and now as they looked at the sudden crash below, there thundered up to
them mighty waves of sound!

The giant plane had struck about twenty feet from the top of a nearly
perpendicular cliff. The terrific crash was felt by seismographs in
Sonor nearly two thousand miles away! The mighty armored hull plowed
into the rocks like some gigantic meteor, the hundreds of thousands of
tons crushing the rocky precipice, grinding it to powder, and shaking
the entire hill. The cliff seemed to buckle and crack. In moments the
plane had been brought to rest, but it had plowed through twenty feet of
rock for nearly an eighth of a mile. For an instant it hung motionless,
perched perilously in the air, its tail jutting out over the little
valley, then slowly, majestically it sank, to strike with a
reverberating crash that shattered the heavy armor plate!

For another instant the great motors continued turning, the roar of the
propellers like some throbbing background to the rending crashes as the
titanic wreck came to rest. Suddenly, with a series of roaring
explosions, the bank of motors in the left wing blew up with awful
force. There was a flash of indescribable brilliance that momentarily
blinded the watching Terrestrians; then there came to the microphone
such waves of sound as it could not reproduce. From the rock on which
rested the fused mass of metal that they knew had been the wing, rose a
great cloud of dust. Still the motors on the other side of the ship
continued roaring and the giant propellers turned. As the blast of air
blew the dust away, the Terrestrians stared in unbounded amazement. Up
from the gaping, broken wing lanced a mighty beam of light of such
dazzling intensity that Arcot swiftly restored them to visibility that
they might shut it out. There was a terrific hissing, crackling roar.
The plane seemed to wobble as it lay there, seemingly recoiling from
that flaming column. Where it touched the cliff there was intense
incandescence that made the rock glow white hot, then flow down in a
sluggish rivulet of molten lava! For five minutes longer this terrific
spectacle lasted, while Arcot withdrew the _Solarite_ to a safer
distance.

The fifty motors of the remaining wing seemed slowing down now--then
suddenly there was such a crash and towering flash of light as no human
being had ever seen before! Up--up into the very clouds it shot its
mighty flame, a blazing column of light that seemed to reach out into
space. The _Solarite_ was hurled back end over end, tumbling, falling.
Even the heavy gyroscopes could not hold it for an instant, but quickly
the straining motors brought them to rest in air that whirled and whined
about them. They were more than twenty miles from the scene of the
explosion, but even at that distance they could see the glow of the
incandescent rock. Slowly, cautiously they maneuvered the _Solarite_
back to the spot, and looked down on a sea of seething lava!

Morey broke the awed silence. "Lord--what power that thing carries! No
wonder they could support it in the air! But--how can they control such
power? What titanic forces!"

Slowly Arcot sent the _Solarite_ away into the night--into the kindly
darkness once more. His voice when he spoke at last was oddly
restrained.

"I wonder what those forces were--they are greater than any man has ever
before seen! An entire hill fused to molten, incandescent rock, not to
mention the tons and tons of metal that made up that ship.

"And such awful forces as these are to be released on our Earth!" For an
interminable period they sat silent as the panorama of hills glided by
at a slow two-hundred miles an hour. Abruptly Arcot exclaimed, "We
_must_ capture a ship. We'll try again--we'll either destroy or capture
it--and either way we're ahead!"

       *       *       *       *       *

Aimlessly they continued their leisurely course across a vast plain.
There were no great mountains on Venus, for this world had known no such
violent upheaval as the making of a moon. The men were lost in thought,
each intent on his own ideas. At length Wade stood up, and walked slowly
back to the power room.

Suddenly the men in the control room heard his call:

"Arcot--quick--the microphone--and rise a mile!"

The _Solarite_ gave a violent lurch as it shot vertically aloft at
tremendous acceleration. Arcot reached over swiftly and snapped the
switch of the microphone. There burst in upon them the familiar roaring
drone of a hundred huge propellers. No slightest hum of motor, only the
vast whining roar of the mighty props.

"Another one! They must have been following the first by a few minutes.
We'll get this one!" Arcot worked swiftly at his switches. "Wade--strap
yourself in the seat where you are--don't take time to come up here."

They followed the same plan which had worked so well before. Suddenly
invisible, the _Solarite_ flashed ahead of the great plane. The titanic
wave of rushing sound engulfed them--then again came the little hiss of
the gas. Now there were no hills in sight, as far as the eye could see.
In the dim light that seemed always to filter through these gray clouds
they could see the distant, level horizon.

Several dragging minutes passed before there was any evident effect; the
men from Earth were waiting for that great ship to waver, to wobble from
its course. Suddenly Arcot gave a cry of surprise. Startled amazement
was written all over his face, as his companions turned in wonderment to
see that he was partially visible! The _Solarite_, too, had become a
misty ghost ship about them; they were becoming visible! Then in an
instant it was gone--and they saw that the huge black bulk behind them
was wavering, turning; the thunderous roar of the propellers fell to a
whistling whine; the ship was losing speed! It dipped, and shot down a
bit--gained speed, then step by step it glided down--down--down to the
surface below. The engines were idling now, the plane running more and
more slowly.

They were near the ground now--and the watchers scarcely breathed. Would
this ship, too, crash? It glided to within a half mile of the
plain--then it dipped once more, and Arcot breathed his relief as it
made a perfect landing, the long series of rollers on the base of the
gigantic hull absorbing the shock of the landing. There were small
streams in the way--a tree or two, but these were obstacles unnoticed by
the gargantuan machine. Its mighty propellers still idling slowly, the
huge plane rolled to a standstill.

Swooping down, the _Solarite_ landed beside it, to be lost in the vast
shadows of the mighty metal walls.

Arcot had left a small radio receiver with Tonlos in Sonor before he
started on this trip, and had given him directions on how to tune in on
the _Solarite_. Now he sent a message to him, telling that the plane had
been brought down, and asking that a squadron of planes be sent at once.

Wade and Arcot were elected to make the first inspection of the Kaxorian
plane, and clad in their cooling suits, they stepped from the
_Solarite_, each carrying, for emergency use, a small hand torch,
burning atomic hydrogen, capable of melting its way through even the
heavy armor of the great plane.

As they stood beside it, looking up at the gigantic wall of metal that
rose sheer beside them hundreds of feet straight up, it seemed
impossible that this mighty thing could fly, that it could be propelled
through the air. In awed silence they gazed at its vast bulk.

Then, like pygmies beside some mighty prehistoric monster, they made
their way along its side, seeking a door. Suddenly Wade stopped short
and exclaimed: "Arcot, this is senseless--we can't do this! The machine
is so big that it'll take us half an hour of steady walking to go around
it. We'll have to use the _Solarite_ to find an entrance!"

It was well that they followed Wade's plan, for the only entrance, as
they later learned, was from the top. There, on the back of the giant,
the _Solarite_ landed--its great weight having no slightest effect on
the Kaxorian craft. They found a trap-door leading down inside. However,
the apparatus for opening it was evidently within the hull, so they had
to burn a hole in the door before they could enter.

What a sight there was for these men of Earth. The low rumble of the
idling engines was barely audible as they descended the long ladder.

There was no resemblance whatever to the interior of a flying machine;
rather, it suggested some great power house, where the energies of half
a nation were generated. They entered directly into a vast hall that
extended for a quarter of a mile back through the great hull, and
completely across the fuselage. To the extreme nose it ran, and
throughout there were scattered little globes that gave off an intense
white light, illuminating all of the interior. Translucent bull's-eyes
obscured the few windows.

All about, among the machines, lay Venerians. Dead they seemed, the
illusion intensified by their strangely blue complexions. The two
Terrestrians knew, however, that they could readily be restored to life.
The great machines they had been operating were humming softly, almost
inaudibly. There were two long rows of them, extending to the end of
the great hall. They suggested mighty generators twenty feet high. From
their tops projected two-feet-thick cylinders of solid fused quartz.
From these extended other rods of fused quartz, rods that led down
through the floor; but these were less bulky, scarcely over eight inches
thick.

The huge generator-like machines were disc-shaped. From these, too, a
quartz rod ran down through the floor. The machines on the further row
were in some way different; those in the front half of the row had the
tubes leading to the floor below, but had no tubes jutting into the
ceiling. Instead, there were many slender rods connected with a vast
switchboard that covered all of one side of the great room. But
everywhere were the great quartz rods, suggesting some complicated water
system. Most of them were painted black, though the main rods leading
from the roof above were as clear as crystal.

Arcot and Wade looked at these gigantic machines in hushed awe. They
seemed impossibly huge; it was inconceivable that all this was but the
power room of an airplane!

Without speaking, they descended to the level below, using a quite
earthly appearing escalator. Despite the motionless figures everywhere,
they felt no fear of their encountering resistance. They knew the
effectiveness of Wade's anesthetic.

The hall they entered was evidently the main room of the plane. It was
as long as the one above, and higher, yet all that vast space was taken
by one single, titanic coil that stretched from wall to wall! Into it,
and from it there led two gigantic columns of fused quartz. That these
were rods, such as those smaller ones above was obvious, but each was
over eight feet thick!

Short they were, for they led from one mighty generator such as they had
seen above, but magnified on a scale inconceivable! At the end of it,
its driving power, its motor, was a great cylindrical case, into which
led a single quartz bar ten inches thick. This bar was alive with
pulsing, glowing fires, that changed and maneuvered and died out over
all its surface and through all its volume. The motor was but five feet
in diameter and a scant seven feet long, yet obviously it was driving
the great machine, for there came from it a constant low hum, a deep
pitched song of awful power. And the huge quartz rod that led from the
titanic coil-cylinder was alive with the same glowing fires that played
through the motor rod. From one side of the generator, ran two objects
that were familiar, copper bus bars. But even these were _three feet
thick_!

The scores of quartz tubes that come down from the floor above joined,
coalesced, and ran down to the great generator, and into it.

They descended to another level. Here were other quartz tubes, but these
led down still further, for this floor contained individual sleeping
bunks, most of them unoccupied, unready for occupancy, though some were
made up.

Down another level; again the bunks, the little individual rooms.

At last they reached the bottom level, and here the great quartz tubes
terminated in a hundred smaller ones, each of these leading into some
strange mechanism. There were sighting devices on it, and there were
ports that opened in the floor. This was evidently the bombing room.

With an occasional hushed word, the Terrestrians walked through what
seemed to be a vast city of the dead, passing sleeping officers, and
crewmen by the hundreds. On the third level they came at last to the
control room. Here were switchboards, control panels, and dozens of
officers, sleeping now, beside their instruments. A sudden dull thudding
sound spun Arcot and Wade around, nerves taut. They relaxed and
exchanged apologetic smiles. An automatic relay had adjusted some
mechanism.

They noted one man stationed apart from the rest. He sat at the very
bow, protected behind eight-inch coronium plates in which were set
masses of fused quartz that were nearly as strong as the metal itself.
These gave him a view in every direction except directly behind him.
Obviously, here was the pilot.

Returning to the top level, they entered the long passages that led out
into the titanic wings. Here, as elsewhere, the ship was brightly
lighted. They came to a small room, another bunk room. There were great
numbers of these down both sides of the long corridor, and along the two
parallel corridors down the wing. In the fourth corridor near the back
edge of the wing, there were bunk rooms on one side, and on the other
were bombing posts.

As they continued walking down the first corridor, they came to a small
room, whence issued the low hum of one of the motors. Entering, they
found the crew sleeping, and the motor idling.

"Good Lord!" Wade exclaimed. "Look at that motor, Arcot! No bigger than
the trunk of a man's body. Yet a battery of these sends the ship along
at a mile a second! What power!"

Slowly they proceeded down the long hall. At each of the fifty engine
mountings they found the same conditions. At the end of the hall there
was an escalator that led one level higher, into the upper wing. Here
they found long rows of the bombing posts and the corresponding quartz
rods.

They returned finally to the control room. Here Arcot spent a long time
looking over the many instruments, the controls, and the piloting
apparatus.

"Wade," he said at last, "I think I can see how this is done. I am going
to stop those engines, start them, then accelerate them till the ship
rolls a bit!" Arcot stepped quickly over to the pilots seat, lifted the
sleeping pilot out, and settled in his place.

"Now, you go over to that board there--that one--and when I ask you to,
please turn on that control--no, the one below--yes--turn it on about
one notch at a time."

Wade shook his head dubiously, a one-sided grin on his face. "All right,
Arcot--just as you say--but when I think of the powers you're playing
with--well, a mistake might be unhealthy!"

"I'm going to stop the motors now," Arcot announced quietly. All the
time they had been on board, they had been aware of the barely inaudible
whine of the motors. Now suddenly, it was gone, and the plane was still
as death!

Arcot's voice sounded unnaturally loud. "I did it without blowing the
ship up after all! Now we're going to try turning the power on!"

Suddenly there was a throaty hum; then quickly it became the low whine;
then, as Arcot turned on the throttle before him, he heard the tens of
thousands of horsepower spring into life--and suddenly the whine was a
low roar--the mighty propellers out there had became a blur--then with
majestic slowness the huge machine moved off across the field!

Arcot shut off the motors and rose with a broad, relieved smile, "Easy!"
he said. They made their way again up through the ship, up through the
room of the tremendous cylinder coil, and then into the power room. Now
the machines were quiet, for the motors were no longer working.

"Arcot, you didn't shut off the biggest machine of all down there. How
come?"

"I couldn't, Wade. It has no shut-off control, and if it did have, I
wouldn't use it. I will tell you why when we get back to the
_Solarite_."

At last they left the mighty machine; walked once more across its broad
metal top. Here and there they now saw the ends of those quartz
cylinders. Once more they entered the _Solarite_, through the air lock,
and took off the cumbersome insulating suits.

As quickly as possible Arcot outlined to the two who had stayed with the
_Solarite_, the things they had seen, and the layout of the great ship.

"I think I can understand the secret of all that power, and it's not so
different from the _Solarite_, at that. It, too, draws its power from
the sun, though in a different way, and it stores it within itself,
which the _Solarite_ does not try to do.

"Light of course, is energy, and therefore, has mass. It exerts
pressure, the impact of its moving units of energy--photons. We have
electrons and protons of matter, and photons of light. Now we know that
the mass of protons and electrons will attract other protons and
electrons, and hold them near--as in a stone, or in a solar system. The
new idea here is that the photons will attract each other ever more and
more powerfully, the closer they get. The Kaxorians have developed a
method of getting them so close together, that they will, for a while at
least, hold themselves there, and with a little 'pressure', will stay
there indefinitely.

"In that huge coil and cylinder we found there we saw the main power
storage tank. That was full of gaseous light-energy held together by its
own attraction, plus a little help of the generator!"

"A little help?" Wade exclaimed. "Quite a little! I'll bet that thing
had a million horsepower in its motor!"

"Yes--but I'll bet they have nearly fifty pounds of light condensed
there--so why worry about a little thing like a million horsepower? They
have plenty more where that comes from.

"I think they go up above the clouds in some way and collect the sun's
energy. Remember that Venus gets twice as much as Earth. They focus it
on those tubes on the roof there, and they, like all quartz tubes,
conduct the light down into the condensers where it is first collected.
Then it is led to the big condenser downstairs, where the final power is
added, and the condensed light is stored.

"Quartz conducts light just as copper conducts electricity--those are
bus bars we saw running around there.

"The bombs we've been meeting recently are, of course, little knots of
this light energy thrown out by that projector mechanism we saw. When
they hit anything, the object absorbs their energy--and is very promptly
volatilized by the heat of the absorption.

"Do you remember that column of hissing radiance we saw shooting out of
the wrecked plane just before it blew up? That was the motor connection,
broken, and discharging free energy. That would ordinarily have
supplied all fifty motors at about full speed. Naturally, when it cut
loose, it was rather violent.

"The main generator had been damaged, no doubt, so it stopped working,
and the gravitational attraction of the photons wasn't enough, without
its influence to hold them bound too long. All those floods of energy
were released instantaneously, of course.

"Look--there come the Lanorians now. I want to go back to Sonor and
think over this problem. Perhaps we can find something that will release
all that energy--though honestly, I doubt it."

Arcot seemed depressed, overawed perhaps, by the sheer magnitude of the
force that lay bound up in the Kaxorian ship. It seemed inconceivable
that the little _Solarite_ could in any way be effective against the
incredible machine.

The Lanorian planes were landing almost like a flock of birds, on the
wings, the fuselage, the ground all about the gigantic ship. Arcot
dropped into a chair, gazing moodily into emptiness, his thoughts on the
mighty giant, stricken now, but only sleeping. In its vast hulk lay such
energies as intelligence had never before controlled; within it he knew
there were locked the powers of the sun itself. What could the
_Solarite_ do against it?

"Oh, I almost forgot to mention it." Arcot spoke slowly, dejectedly. "In
the heat of the attack back there it went practically unnoticed. Our
only weapon beside the gas is useless now. Do you remember how the ship
seemed to lose its invisibility for an instant? I learned why when we
investigated the ship. Those men are physicists of the highest order. We
must realize the terrible forces, both physical and mental that we are
to meet. They've solved the secret of our invisibility, and now they can
neutralize it. They began using it a bit too late this time, but they
had located the radio-produced interference caused by the ship's
invisibility apparatus, and they were sending a beam of interfering
radio energy at us. We are invisible only by reason of the vibration of
the molecules in response to the radio impressed oscillations. The
molecules vibrate in tune, at terrific frequency, and the light can pass
perfectly. What will happen, however, if someone locates the source of
the radio waves? It'll be simple for them to send out a radio beam and
touch our invisible ship with it. The two radio waves impressed on us
now will be out of step and the interference will instantly make us
visible. We can no longer attack them with our atomic hydrogen blast, or
with the gas--both are useless unless we can get close to them, and we
can't come within ten miles of them now. Those bombs of theirs are
effective at that distance."

Again he fell silent, thinking--hoping for an idea that would once more
give them a chance to combat the Kaxorians. His three companions,
equally depressed and without a workable idea, remained silent. Abruptly
Arcot stood up.

"I'm going to speak with the Commander-in-Field here. Then we can start
back for Sonor--and maybe we had better head for home. It looks as
though there is little we can do here."

Briefly he spoke to the young Venerian officer, and told him what he had
learned about the ship. Perhaps they could fly it to Sonor; or it could
be left there undestroyed if he would open a certain control just before
he left. Arcot showed him which one--it would drain out the power of the
great storage tank, throwing it harmlessly against the clouds above. The
Kaxorians might destroy the machine if they wanted to--Arcot felt that
they would not wish to. They would hope, with reason, they might
recapture it! It would be impossible to move that tremendous machine
without the power that its "tank" was intended to hold.




VII


Slowly they cruised back to Sonor, Arcot still engrossed in thought.
Would it be that Venus would fall before the attack of the mighty
planes, that they would sweep out across space, to Earth--to Mars--to
other worlds, a cosmic menace? Would the mighty machines soon be
circling Earth? Guided missiles with atomic warheads could combat them,
perhaps, as could the molecular motion machines. Perhaps these could be
armored with twenty-inch steel walls, and driven into the great
propellers, or at miles a second, into the ship itself! But these ships
would require long hours, days, even weeks to build, and in that time
the Kaxorian fleet would be ready. It would attack Earth within six days
now! What hope was there to avert incalculable destruction--if not
outright defeat?

In despair Arcot turned and strode quickly down the long hallway of the
_Solarite_. Above him he could hear the smooth, even hum of the sweetly
functioning generator, but it only reminded him of the vastly greater
energies he had seen controlled that night. The thudding relays in the
power room, as Wade maneuvered the ship, seemed some diminutive mockery
of the giant relays he had seen in the power room of the Kaxorian plane.

He sat down in the power room, looking at the stacked apparatus, neatly
arranged, as it must be, to get all this apparatus in this small space.
Then at last he began to think more calmly. He concentrated on the
greatest forces known to man--and there were only two that even occurred
to him as great! One was the vast energies he had that very night
learned of; the other was the force of the molecules, the force that
drove his ship.

He had had no time to work out the mathematics of the light compression,
mathematics that he now knew would give results. There remained only the
molecular motion. What could he do with it that he had not done?

He drew out a small black notebook. In it were symbols, formulas, and
page after page of the intricate calculus that had ended finally in the
harnessing of this great force that was even now carrying him smoothly
along.

Half an hour later he was still busy--covering page after page with
swiftly written formulas. Before him was a great table of multiple
integers, the only one like it known to exist in the System, for the
multiple calculus was an invention of Arcot's. At last he found the
expression he wanted, and carefully he checked his work, excitedly
though now, with an expression of eager hope--it seemed logical--it
seemed correct--

"Morey--oh, Morey," he called, holding his enthusiasm in check, "if you
can come here--I want you to check some math for me. I've done it--and I
want to see if you get the same result independently!" Morey was a more
careful mathematician than he, and it was to him Arcot turned for
verification of any new discovery.

Following the general directions Arcot gave him, Morey went through the
long series of calculations--and arrived at the same results. Slowly he
looked up from the brief expression with which he had ended.

It was not the formula that astonished him--it was its physical
significance.

"Arcot--do you think we can make it?"

There was a new expression in Arcot's eyes, a tightness about his mouth.

"I hope so, Morey. If we don't, Lanor is lost beyond a doubt--and
probably Earth is, too. Wade--come here a minute, will you? Let Fuller
take the controls, and tell him to push it. We have to get to work on
this."

Rapidly Arcot explained their calculations--and the proof he had gotten.

"Our beam of molecular motion-controlling energy directs all molecular
motion to go at right angles to it. The mechanism so far has been a
field inside a coil really, but if these figures are right, it means
that we can project that field to a considerable distance even in air.
It'll be a beam of power that will cause all molecules in its path to
move at right angles to it, and in the direction we choose, by reversing
the power in the projector. That means that no matter how big the thing
is, we can tear it to pieces; we'll use its own powers, its own
energies, to rip it, or crush it.

"Imagine what would happen if we directed this against the side of a
mountain--the entire mass of rock would at once fly off at unimaginable
speed, crashing ahead with terrific power, as all the molecules suddenly
moved in the same direction. Nothing in all the Universe could hold
together against it! It's a disintegration ray of a sort--a ray that
will tear, or crush, for we can either make one half move away from the
other--or we can reverse the power, and make one half drive toward the
other with all the terrific power of its molecules! It is
omnipotent--hmmm--" Arcot paused, narrowing his eyes in thought.

"It has one limitation. Will it reach far in the air? In vacuum it
should have an infinite range--in the atmosphere all the molecules of
the air will be affected, and it will cause a terrific blast of icy
wind, a gale at temperatures far below zero! This will be even more
effective here on Venus!

"But we must start designing the thing at once! Take some of the
Immorpho and give me some, and we can let the sleep accumulate till we
have more time! Look--we're in Sonor already! Land us, Fuller--right
where we were, and then come back here. We're going to need you!"

The gorgeous display of a Venerian dawn was already coloring the east as
the great buildings seemed to rise silently about them. The sky, which
had been a dull luminous gray, a gray that rapidly grew brighter and
brighter, was now like molten silver, through which were filtering the
early rays of the intense sun. As the sun rose above the horizon, though
invisible for clouds, it still was traceable by the wondrous shell pink
that began to suffuse the ten mile layer of vapor. The tiny droplets
were, however, breaking the clear light into a million rainbows, and all
about the swiftly deepening pink were forming concentric circles of
blue, of green, orange, and all the colors of the rainbow, repeated time
after time--a wondrous halo of glowing color, which only the doubly
intense sun could create.

"It's almost worth missing the sun all day to see their sunrises and
sunsets," Fuller commented. The men were watching it, despite their
need for haste. It was a sight the like of which no Earthman had ever
before seen.

Immediately, then, they plunged into the extremely complex calculation
of the electrical apparatus to produce the necessary fields. To get the
effect they wanted, they must have two separate fields of the director
ray, and a third field of a slightly different nature, which would cause
the director ray to move in one direction only. It would be
disconcerting, to say the least, if the director ray, by some mistake,
should turn upon them!

The work went on more swiftly than they had considered possible, but
there was still much to be done on the theoretical end of the job alone
when the streets about them began to fill. They noticed that a large
crowd was assembling, and shortly after they had finished, after some of
these people had stood there for more than an hour and a half, the crowd
had grown to great size.

"From the looks of that collection, I should say we are about to become
the principals in some kind of a celebration that we know nothing about.
Well, we're here, and in case they want us, we're ready to come."

The guard that always surrounded the _Solarite_ had been doubled, and
was maintaining a fairly large clear area about the ship.

Shortly thereafter they saw one of the high officials of Lanor come down
the walk from the governmental building, walking toward the _Solarite_.

"Time for us to appear--and it may as well be all of us this time. I'll
tell you what they say afterward, Wade. They've evidently gone to
considerable trouble to get up this meeting, so let's cooperate. I hate
to slow up the work, but we'll try to make it short."

The four Terrestrians got into their cooling suits, and stepped outside
the ship. The Lanorian dignitary left his guard, walked up to the
quartet from Earth with measured tread, and halted before them.

"Earthmen," he began in a deep, clear voice, "we have gathered here this
morning to greet you and thank you for the tremendous service you have
done us. Across the awful void of empty space you have journeyed forty
million miles to visit us, only to discover that Venerians were making
ready to attack your world. Twice your intervention has saved our city.

"There is, of course, no adequate reward for this service; we can in no
way repay you, but in a measure we may show our appreciation. We have
learned from the greatest psychologist of our nation, Tonlos, that in
your world aluminum is plentiful, but gold and platinum are rare, and
that morlus is unknown. I have had a small token made for you, and your
friends. It is a little plaque, a disc of morlus, and on it there is a
small map of the Solar System. On the reverse side there is a globe of
Venus, with one of Earth beside it, as well as our men could copy the
small globe you have given us. The northern hemisphere of each is
depicted--America, your nation, and Lanor, ours, thus being shown. We
want you, and each of your friends, to accept these. They are symbols of
your wonderful flight across space!" The Venerians turned to each of the
Terrestrians and presented each with a small metal disc.

Arcot spoke for the Terrestrians.

"On behalf of myself and my friends here, two of whom have not had an
opportunity to learn your language, I wish to thank you for your great
help when we most needed it. You, perhaps, have saved more than a
city--you may have made it possible to save a world--our Earth. But the
battle here has only begun.

"There are now in the Kaxorian camp eighteen great ships. They have been
badly defeated in the three encounters they have had with the _Solarite_
so far. But no longer will they be vulnerable to our earlier methods of
attack. Your spies report that the first plane, the plane which was
first attacked by the _Solarite_, is still undergoing repairs. These
will be completed within two days, and then, when they can leave a base
guard of two ships, they will attack once more. Furthermore, they will
attack with a new weapon. They have destroyed the usefulness of our
weapon, invisibility, and in turn, now have it to use against us! We
must seek out some new weapon. I hope we are on the right track now, but
every moment is precious, and we must get back to the work. This address
must be short. Later, when we have completed our preliminary work, we
will have to give plans to your workmen, which you will be able to turn
into metal, for we lack the materials. With this help we may succeed,
despite our handicap."

The address was terminated at once. The Lanorians were probably
disappointed, but they fully realized the necessity for haste.

"I wish Terrestrian orators spoke like that," remarked Morey as they
returned to the ship. "He said all there was to say, but he didn't run
miles of speech doing it. He was a very forceful speaker, too!"

"People who speak briefly and to the point generally are," Arcot said.

It was nearly noon that day before the theoretical discussion had been
reduced to practical terms. They were ready to start work at once, but
they had reason to work cheerfully now. Even through air they had found
their ray would be able to reach thirty-five miles! They would be well
out of the danger zone while attacking the gigantic planes of Kaxor.

Morey, Wade and Arcot at once set to work constructing the electrical
plant that was to give them the necessary power. It was lucky indeed
that they had brought the great mass of spare apparatus! They had more
than enough to make all the electrical machinery. The tubes, the coils,
the condensers, all were there. The generator would easily supply the
power, for the terrific forces that were to destroy the Kaxorian ships
were to be generated in the plane itself. It was to destroy itself; the
_Solarite_ would merely be the detonator to set it off!

       *       *       *       *       *

While the physicists were busy on this, Fuller was designing the
mechanical details of the projector. It must be able to turn through a
spherical angle of 180 degrees, and was necessarily controlled
electrically from the inside. The details of the projector were worked
out by six that evening, and the numerous castings and machined pieces
that were to be used were to be made in the Venerian machine shops.

One difficulty after another arose and was overcome. Night came on, and
still they continued work. The Venerian workmen had promised to have the
apparatus for them by ten o'clock the next morning--or what corresponded
to ten o'clock.

Shortly after three o'clock that morning they had finished the
apparatus, had connected all the controls, and had placed the last of
the projector directors. Except for the projector they were ready, and
Morey, Wade and Fuller turned in to get what sleep they could. But
Arcot, telling them there was something he wished to get, took another
dose of Immorpho and stepped out into the steaming rain.

A few minutes after ten the next morning Arcot came back, followed by
half a dozen Venerians, each carrying a large metal cylinder in a
cradle. These were attached to the landing gear of the _Solarite_ in
such fashion that the fusing of one piece of wire would permit the
entire thing to drop free.

"So _that's_ what you hatched out, eh? What is it?" asked Wade as he
entered the ship.

"Just a thing I want to try out--and I'm going to keep it a deep, dark
secret for a while. I think you'll get quite a surprise when you see
those bombs in action! They're arranged to be released by turning
current into the landing lights. We'll have to forgo lights for the
present, but I needed the bombs more.

"The mechanics have finished working on your projector parts, Fuller,
and they'll be over here in a short time. Here comes the little gang I
asked to help us. You can direct them." Arcot paused and scowled with
annoyance. "Hang it all--when they drill into the outer wall, we'll lose
the vacuum between the two walls, and all that hot air will come in.
This place will be roasting in a short time. We have the molecular
motion coolers, but I'm afraid they won't be much good. Can't use the
generator--it's cut off from the main room by vacuum wall.

"I think we'd better charge up the gas tanks and the batteries as soon
as this is done. Then tonight we'll attack the Kaxorian construction
camp. I've just learned that no spy reports have been coming in, and I'm
afraid they'll spring a surprise."

Somewhat later came the sound of drills, then the whistling roar as the
air sucked into the vacuum, told the men inside that the work was under
way. It soon became uncomfortably hot as, the vacuum destroyed, the heat
came in through all sides. It was more than the little molecular coolers
could handle, and the temperature soon rose to about a hundred and
fifteen. It was not as bad as the Venerian atmosphere, for the air
seemed exceedingly dry, and the men found it possible to get along
without cooling suits, if they did not work. Since there was little they
could do, they simply relaxed.

It was nearly dark before the Lanorians had finished their work, and the
gas tanks had been recharged. All that time Arcot had spent with Tonlos
determining the position of the Kaxorian construction camp. Spy reports
and old maps had helped, but it was impossible to do very accurate work
by these means.

It was finally decided that the Kaxorian construction camp was about
10,500 miles to the southwest. The _Solarite_ was to start an hour after
dark. Travelling westward at their speed, they hoped to reach the camp
just after nightfall.




VIII


The _Solarite_ sped swiftly toward the southwest. The sky slowly grew
lighter as the miles flashed beneath them. They were catching up with
the sun. As they saw the rolling ocean beneath them give way to low
plains, they realized they were over Kaxorian land. The _Solarite_ was
flying very high, and as they showed no lights, and were not using the
invisibility apparatus, they were practically undetectable. Suddenly
they saw the lights of a mighty city looming far off to the east.

"It's Kanor. Pass well to the west of it. That's their capital. We're on
course." Arcot spoke from his position at the projector, telling Wade
the directions to follow on his course to the berth of the giant planes.

The city dropped far behind them in moments, followed by another, and
another. At length, veering southward into the dusk, they entered a
region of low hills, age-old folds in the crust of the planet, rounded
by untold millennia of torrential rains.

"Easy, Wade. We are near now." Mile after mile they flashed ahead at
about a thousand miles an hour--then suddenly they saw far off to the
east a vast glow that reached into the sky, painting itself on the
eternal clouds miles above.

"There it is, Wade. Go high, and take it easy!"

Swiftly the _Solarite_ climbed, hovering at last on the very rim of the
cloud blanket, an invisible mote in a sea of gray mist. Below them they
saw a tremendous field carved, it seemed, out of the ancient hills. From
this height all sense of proportion was lost. It seemed but an ordinary
field, with eighteen ordinary airplanes resting on it. One of these now
was moving, and in a moment it rose into the air! But there seemed to be
no men on all the great field. They were invisibly small from this
height.

Abruptly Arcot gave a great shout. "That's their surprise! They're ready
far ahead of the time we expected! If all that armada gets in the air,
we're done! Down, Wade, to within a few hundred feet of the ground, and
close to the field!"

The _Solarite_ flashed down in a power dive--down with a sickening
lurch. A sudden tremendous weight seemed to crush them as the ship was
brought out of the dive not more than two hundred feet from the ground.
Close to blacking out, Wade nevertheless shot it in as close to the
field as he dared. Anxiously he called to Arcot, who answered with a
brief "Okay!" The planes loomed gigantic now, their true proportions
showing clearly against the brilliant light of the field. A tremendous
wave of sound burst from the loudspeaker as the planes rolled across the
ground to leap gracefully into the air--half a million tons of metal!

From the _Solarite_ there darted a pale beam of ghostly light, faintly
gray, tinged with red and green--the ionized air of the beam. It moved
in a swift half circle. In an instant the whirr of the hundreds,
thousands of giant propellers was drowned in a terrific roar of air.
Great snowflakes fell from the air before them; it was white with the
solidified water vapor. Then came a titanic roar and the planet itself
seemed to shake! A crash, a snapping and rending as a mighty fountain of
soil and rock cascaded skyward, and with it, twisting, turning, hurled
in a dozen directions at once, twelve titanic ships reeled drunkenly
into the air!

For a barely perceptible interval there was an oppressive silence as the
ray was shut off. Then a bedlam of deafening sound burst forth anew, a
mighty deluge of unbearable noise as the millions of tons of pulverized
rock, humus and metal fell back. Some of it had ascended for miles; it
settled amid a howling blizzard--snow that melted as it touched the
madly churned airfield.

High above there were ten planes flying about uncertainly. Suddenly one
of these turned, heading for the ground far below, its wings screaming
their protest as the motors roared, ever faster, with the gravity of the
planet aiding them. There was a rending, crackling crash as the wings
suddenly bent back along the sides. An instant later the fuselage tore
free, rocketing downward; the wings followed more slowly--twisting,
turning, dipping in mile-long swoops.

The _Solarite_ shot away from the spot at maximum speed--away and up,
with a force that nailed the occupants to the floor. Before they could
turn, behind them flared a mighty gout of light that struck to the very
clouds above, and all the landscape, for miles about, was visible in the
glare of the released energy.

As they turned, they saw on the plain, below a tremendous crater, in
its center a spot that glowed white and bubbled like the top of a huge
cauldron.

Nine great planes were circling in the air; then in an instant they were
gone, invisible. As swiftly the _Solarite_ darted away with a speed that
defied the aim of any machine.

High above the planes they went, for with his radar Arcot could trace
them. They were circling, searching for the _Solarite_.

The tiny machine was invisible in the darkness, but its invisibility was
not revealed by the Kaxorian's radio detectors. In the momentary lull,
Fuller asked a question.

"Wade, how is it that those ships can be invisible when they are driven
by light, and have the light stored in them? They're perfectly
transparent. Why can't we see the light?"

"They are storing the light. It's bound--it can't escape. You can't see
light unless it literally hits you in the eye. Their stored light can't
reach you, for it is held by its own attraction and by the special field
of the big generators."

They seemed to be above one of the Kaxorian planes now. Arcot caught the
roar of the invisible propellers.

"To the left, Wade--faster--hold it--left--ah!" Arcot pushed a button.

Down from the _Solarite_ there dropped a little canister, one of the
bombs that Arcot had prepared the night before. To hit an invisible
target is ordinarily difficult, but when that target is far larger than
the proverbial side of a barn, it is not very difficult, at that. But
now Arcot's companions watched for the crash of the explosion, the flash
of light. What sort of bomb was it that Arcot hoped would penetrate that
tremendous armor?

Suddenly they saw a great spot of light, a spot that spread with
startling rapidity, a patch of light that ran, and moved. It flew
through the air at terrific speed. It was a pallid light, green and wan
and ghostly, that seemed to flow and ebb.

For an instant Morey and the others stared in utter surprise. Then
suddenly Morey burst out laughing.

"Ho--you win, Arcot. That was one they didn't think of, I'll bet!
Luminous paint--and by the hundred gallon! Radium paint, I suppose, and
no man has ever found how to stop the glow of radium. That plane sticks
out like a sore thumb!"

Indeed, the great luminous splotch made the gigantic plane clearly
evident against the gray clouds. Visible or not, that plane was marked.

Quickly Arcot tried to maneuver the _Solarite_ over another of the great
ships, for now the danger was only from those he could not see. Suddenly
he had an idea.

"Morey--go back to the power room and change the adjustment on the
meteorite avoider to half a mile!" At once Morey understood his plan,
and hastened to put it into effect.

The illuminated plane was diving, twisting wildly now. The _Solarite_
flashed toward it with sickening speed, then suddenly the gigantic bulk
of the plane loomed off to the right of the tiny ship, the great metal
hull, visible now, rising in awesome might. They were too near; they
shot away to a greater distance--then again that ghostly beam reached
out--and for just a fraction of a second it touched the giant plane.

The titanic engine of destruction seemed suddenly to be in the grip of
some vastly greater Colossus--a clutching hand that closed! The plane
jumped back with an appalling crash, a roar of rending metal. For an
instant there came the sound like a mighty buzz-saw as the giant
propellers of one wing cut into the body of the careening plane. In that
instant, the great power storage tank split open with an impact like the
bursting of a world. The _Solarite_ was hurled back by an explosion that
seemed to rend the very atoms of the air, and all about them was a
torrid blaze of heat and light that seemed to sear their faces and hands
with its intensity.

Then in a time so brief that it seemed never to have happened, it was
gone, and only the distant drone of the other ships' propellers came to
them. There was no luminous spot. The radium paint had been destroyed
in the only possible way--it was volatilized through all the atmosphere!

The Terrestrians had known what to expect; had known what would happen;
and they had not looked at the great ship in that last instant. But the
Kaxorians had naturally been looking at it. They had never seen the sun
directly, and now they had been looking at a radiance almost as
brilliant. They were temporarily blinded; they could only fly a straight
course in response to the quick order of their squadron commander.

And in that brief moment that they were unable to watch him, Arcot
dropped two more bombs in quick succession. Two bright spots formed in
the black night. No longer did these planes feel themselves
invulnerable, able to meet any foe! In an instant they had put on every
last trace of power, and at their top speed they were racing west, away
from their tiny opponent--in the only direction that was open to them.

But it was useless. The _Solarite_ could pick up speed in half the time
they could, and in an instant Arcot again trained his beam on the mighty
splotch of light that was a fleeing plane.

Out of the darkness came a ghostly beam, for an instant of time so short
that before the explosive shells of the other could be trained on it,
the _Solarite_ had moved. Under that touch the mighty plane began
crumbling, then it splintered beneath the driving blow of the great
wing, as it shot toward the main body of the plane at several miles a
second--driving into and through it! The giant plane twisted and turned
as it fell swiftly downward into the darkness--and, again there came
that world-rocking explosion, and the mighty column of light.

Again and yet again the _Solarite_ found and destroyed Kaxorian
super-planes, protected in the uneven conflict by their diminutive size
and the speed of their elusive maneuvering.

But to remind the men of the _Solarite_ that they were not alone, there
came a sudden report just behind them, and they turned to see that one
of the energy bombs had barely fallen short! In an instant the
comparative midget shot up at top speed, out of danger. It looped and
turned, hunting, feeling with its every detector for that other ship.
The great planes were spread out now. In every direction they could be
located--and all were leaving the scene of the battle. But one by one
the _Solarite_ shot after them, and always the speed of the little ship
was greater.

Two escaped. They turned off their useless invisibility apparatus and
vanished into the night.

The _Solarite_, supported by her vertical lift units, coasted toward a
stop. The drone of the fleeing super-planes diminished and was gone, and
for a time the thrum of the generator and the tap-dance of relays
adjusting circuits was the only sound aboard.

Wade sighed finally. "Well, gentlemen, now we've got it, what do we do
with it?"

"What do you mean?" Morey asked.

"Victory. The Jack-pot. Having the devices we just demonstrated, we are
now the sole owners, by right of conquest, of one highly disturbed
nation of several million people. With that gadget there, we can pick it
up and throw it away.

"Personally, I have a feeling that we've just won the largest white
elephant in history. We don't just walk off and leave it, you know. We
don't want it. But we've got it.

"Our friends in Sonor are not going to want the problem either; they
just wanted the Kaxorians combed out of their hair.

"As I say--we've got it, now--but what do we do with it?"

"It's basically their problem, isn't it?" protested Fuller. Morey looked
somewhat stricken, and thoroughly bewildered. "I hadn't considered that
aspect very fully; I've been too darned busy trying to stay alive."

Wade shook his head. "Look, Fuller-it was their problem before, too,
wasn't it? How'd they handle it? If you just let them alone, what do
you suppose they'll do with the problem this time?"

"The same thing they did before," Arcot groaned. "I'm tired. Let's get
some sleep first, anyway."

"Sure; that makes good sense," Wade agreed. "Sleep on it, yes. But go to
sleep on it--well, that's what the not-so-bright Sonorans tried doing.

"And off-hand, I'd say we were elected. The Kaxorians undoubtedly have a
nice, two thousand year old hatred for the Sonorans who so snobbishly
ignored them, isolated them, and considered them unfit for association.
The Sonorans, on the other hand, are now thoroughly scared, and will be
feeling correspondingly vindictive. They won this time by a fluke--our
coming. I can just see those two peoples getting together and settling
any kind of sensible, long-term treaty of mutual cooperation!"

Arcot and Morey both nodded wearily. "That is so annoyingly correct,"
Morey agreed. "And you know blasted well none of us is going to sleep
until we have some line of attack on this white elephant disposal
problem. Anybody any ideas?"

Fuller looked at the other three. "You know, in design when two
incompatible materials must be structurally united, we tie each to a
third material that is compatible with both.

"Sonor didn't win this fight. Kaxor didn't win it. Earth--in the
_persona_ of the _Solarite_--did. Earth isn't mad at anybody, hasn't
been damaged by anybody, and hasn't been knowingly ignoring anybody.

"The Sonorans want to be let alone; it won't work, but they can learn
that. I think if we run the United Nations in on this thing, we may be
able to get them to accept our white elephant for us.

"They'll be making the same mistake Sonor did if they don't--knowingly
ignoring the existence of a highly intelligent and competent race. It
doesn't seem to work, judging from history both at home and here."

The four looked at each other, and found agreement.

"That's something more than a problem to sleep on," Morey said. "I'll
get in touch with Sonor and tell 'em the shooting is over, so they can
get some sleep too.

"It's obvious a bunch of high-power research teams are going to be
needed in both countries. Earth has every reason to respect Sonoran
mental sciences as well as Kaxorian light-engineering. And Earth--as we
just thoroughly demonstrated--has some science of her own. Obviously,
the interaction of the three is to the maximum advantage of each--and
will lead to a healing of the breach that now exists."

Arcot looked up and yawned. "I'm putting this on autopilot at twenty
miles up, and going to sleep. We can kick this around for a month
anyway--and this is not the night to start."

"The decision is unanimous," Wade grinned.




BOOK THREE

THE BLACK STAR PASSES




PROLOGUE


Taj Lamor gazed steadily down at the vast dim bulk of the ancient city
spread out beneath him. In the feeble light of the stars its mighty
masses of up-flung metal buildings loomed strangely, like the shells of
some vast race of crustacea, long extinct. Slowly he turned, gazing now
out across the great plaza, where rested long rows of slender, yet
mighty ships. Thoughtfully he stared at their dim, half-seen shapes.

Taj Lamor was not human. Though he was humanoid, Earth had never seen
creatures just like him. His seven foot high figure seemed a bit
ungainly by Terrestrial standards, and his strangely white, hairless
flesh, suggesting unbaked dough, somehow gave the impression of
near-transparency. His eyes were disproportionately large, and the black
disc of pupil in the white corneas was intensified by contrast. Yet
perhaps his race better deserved the designation _homo sapiens_ than
Terrestrians do, for it was wise with the accumulated wisdom of
uncounted eons.

He turned to the other man in the high, cylindrical, dimly lit tower
room overlooking the dark metropolis, a man far older than Taj Lamor,
his narrow shoulders bent, and his features grayed with his years. His
single short, tight-fitting garment of black plastic marked him as one
of the Elders. The voice of Taj Lamor was vibrant with feeling:

"Tordos Gar, at last we are ready to seek a new sun. Life for our race!"

A quiet, patient, imperturbable smile appeared on the Elder's face and
the heavy lids closed over his great eyes.

"Yes," he said sadly, "but at what cost in tranquility! The discord, the
unrest, the awakening of unnatural ambitions--a dreadful price to pay
for a questionable gain. Too great a price, I think." His eyes opened,
and he raised a thin hand to check the younger man's protest. "I know--I
know--in this we do not see as one. Yet perhaps some day you will learn
even as I have that to rest is better than to engage in an endless
struggle. Suns and planets die. Why should races seek to escape the
inevitable?" Tordos Gar turned slowly away and gazed fixedly into the
night sky.

Taj Lamor checked an impatient retort and sighed resignedly. It was this
attitude that had made his task so difficult. Decadence. A race on an
ages-long decline from vast heights of philosophical and scientific
learning. Their last external enemy had been defeated millennia in the
past; and through easy forgetfulness and lack of strife, ambition had
died. Adventure had become a meaningless word.

Strangely, during the last century a few men had felt the stirrings of
long-buried emotion, of ambition, of a craving for adventure. These were
throwbacks to those ancestors of the race whose science had built their
world. These men, a comparative handful, had been drawn to each other by
the unnatural ferment within them; and Taj Lamor had become their
leader. They had begun a mighty struggle against the inertia of ages of
slow decay, had begun a search for the lost secrets of a
hundred-million-year-old science.

Taj Lamor raised his eyes to the horizon. Through the leaping curve of
the crystal clear roof of their world glowed a blazing spot of yellow
fire. A star--the brightest object in a sky whose sun had lost its
light. A point of radiance that held the last hopes of an incredibly
ancient race.

The quiet voice of Tordos Gar came through the semidarkness of the
room, a pensive, dreamlike quality in its tones.

"You, Taj Lamor, and those young men who have joined you in this futile
expedition do not think deeply enough. Your vision is too narrow. You
lack perspective. In your youth you cannot think on a cosmic scale." He
paused as though in thought, and when he continued, it seemed almost as
though he were speaking to himself.

"In the far, dim past fifteen planets circled about a small, red sun.
They were dead worlds--or rather, worlds that had not yet lived. Perhaps
a million years passed before there moved about on three of them the
beginnings of life. Then a hundred million years passed, and those
first, crawling protoplasmic masses had become animals, and plants, and
intermediate growths. And they fought endlessly for survival. Then more
millions of years passed, and there appeared a creature which slowly
gained ascendancy over the other struggling life forms that fought for
the warmth of rays of the hot, red sun.

"That sun had been old, even as the age of a star is counted, before its
planets had been born, and many, many millions of years had passed
before those planets cooled, and then more eons sped by before life
appeared. Now, as life slowly forced its way upward, that sun was nearly
burned out. The animals fought, and bathed in the luxury of its rays,
for many millennia were required to produce any noticeable change in its
life-giving radiations.

"At last one animal gained the ascendancy. Our race. But though one
species now ruled, there was no peace. Age followed age while
semi-barbaric peoples fought among themselves. But even as they fought,
they learned.

"They moved from caves into structures of wood and stone--and
engineering had its beginning. With the buildings came little chemical
engines to destroy them; warfare was developing. Then came the first
crude flying-machines, using clumsy, inefficient engines. Chemical
engines! Engines so crude that one could watch the flow of their fuel!
One part in one hundred thousand million of the energy of their
propellents they released to run the engines, and they carried fuel in
such vast quantities that they staggered under its load as they left the
ground! And warfare became world-wide. After flight came other machines
and other ages. Other scientists began to have visions of the realms
beyond, and they sought to tap the vast reservoirs of Nature's energies,
the energies of matter.

"Other ages saw it done--a few thousand years later there passed out
into space a machine that forced its way across the void to another
planet! And the races of the three living worlds became as one--but
there was no peace.

"Swiftly now, science grew upon itself, building with ever faster steps,
like a crystal which, once started, forms with incalculable speed.

"And while that science grew swiftly greater, other changes took place,
changes in our universe itself. Ten million years passed before the
first of those changes became important. But slowly, steadily our
atmosphere was drifting into space. Through ages this gradually became
apparent. Our worlds were losing their air and their water. One planet,
less favored than another, fought for its life, and space itself was
ablaze with the struggles of wars for survival.

"Again science helped us. Thousands of years before, men had learned how
to change the mass of matter into energy, but now at last the process
was reversed, and those ancestors of ours could change energy into
matter, any kind of matter they wished. Rock they took, and changed it
to energy, then that energy they transmuted to air, to water, to the
necessary metals. Their planets took a new lease of life!

"But even this could not continue forever. They must stop that loss of
air. The process they had developed for reformation of matter admitted
of a new use. Creation! They were now able to make new elements,
elements that had never existed in nature! They designed atoms as, long
before, their fathers had designed molecules. At last their problem was
solved. They made a new form of matter that was clearer than any
crystal, and yet stronger and tougher than any metal known. Since it
held out none of the sun's radiations, they could roof their worlds with
it and keep their air within!

"This was a task that could not be done in a year, nor a decade, but all
time stretched out unending before them. One by one the three planets
became tremendous, roofed-in cities. Only their vast powers, their
mighty machines made the task possible, but it was done."

The droning voice of Tordos Gar ceased. Taj Lamor, who had listened with
a mixture of amusement and impatience to the recital of a history he
knew as well as the aged, garrulous narrator, waited out of the inborn
respect which every man held for the Elders. At length he exclaimed: "I
see no point--"

"But you will when I finish--or, at least, I hope you will." Tordos
Gar's words and tone were gently reproving. He continued quietly:

"Slowly the ages drifted on, each marked by greater and greater triumphs
of science. But again and again there were wars. Some there were in
which the population of a world was halved, and all space for a billion
miles about was a vast cauldron of incandescent energy in which
tremendous fleets of space ships swirled and fused like ingredients in
some cosmic brew. Forces were loosed on the three planets that sent even
their mighty masses reeling drunkenly out of their orbits, and space
itself seemed to be torn by the awful play of energies.

"Always peace followed--a futile peace. A few brief centuries or a few
millennia, and again war would flame. It would end, and life would
continue.

"But slowly there crept into the struggle a new factor, a darkening
cloud, a change that came so gradually that only the records of
instruments, made during a period of thousands of years, could show it.
Our sun had changed from bright red to a deep, sullen crimson, and ever
less and less heat poured from it. It was waning!

"As the fires of life died down, the people of the three worlds joined
in a conflict with the common menace, death from the creeping cold of
space. There was no need for great haste; a sun dies slowly. Our
ancestors laid their plans and carried them out. The fifteen worlds were
encased in shells of crystal. Those that had no atmosphere were given
one. Mighty heating plants were built--furnaces that burned matter,
designed to warm a world! At last a state of stability had been reached,
for never could conditions change--it seemed. All external heat and
light came from far-off stars, the thousands of millions of suns that
would never fail.

"Under stress of the Great Change one scarcely noticed, yet almost
incredible, transformation had occurred. We had learned to live with
each other. We had learned to think, and enjoy thinking. As a species we
had passed from youth into maturity. Advancement did not stop; we went
on steadily toward the goal of all knowledge. At first there was an
underlying hope that we might some day, somehow, escape from these
darkened, artificial worlds of ours, but with the passing centuries this
grew very dim and at length was forgotten.

"Gradually as millennia passed, much ancient knowledge was also
forgotten. It was not needed. The world was unchanging, there was no
strife, and no need of strife. The fifteen worlds were warm, and
pleasant, and safe. Without fully realizing it, we had entered a period
of rest. And so the ages passed; and there were museums and libraries
and laboratories; and the machines of our ancestors did all necessary
work. So it was--until less than a generation ago. Our long lives were
pleasant, and death, when it came, was a sleep. And then--"

"And then," Taj Lamor interrupted, a sharp edge of impatience in his
tone, "some of us awakened from our stupor!"

The Elder sighed resignedly. "You cannot see--you cannot see. You would
start that struggle all over again!" His voice continued in what Taj
Lamor thought of as a senile drone, but the younger man paid scant
attention. His eyes and thoughts were centered on that brilliant yellow
star, the brightest object in the heavens. It was that star, noticeably
brighter within a few centuries, that had awakened a few men from their
mental slumbers.

They were throwbacks, men who had the divine gift of curiosity; and
sparked by their will to know, they had gone to the museums and looked
carefully at the ancient directions for the use of the telectroscope,
the mighty electrically amplified vision machine, had gazed through it.
They had seen a great sun that seemed to fill all the field of the
apparatus with blazing fire. A sun to envy! Further observation had
revealed that there circled about the sun a series of planets, five,
definitely; two more, probably; and possibly two others.

Taj Lamor had been with that group, a young man then, scarcely more than
forty, but they had found him a leader and they had followed him as he
set about his investigation of the ancient books on astronomy.

How many, many hours had he studied those ancient works! How many times
had he despaired of ever learning their truths, and gone out to the roof
of the museum to stand in silent thought looking out across the awful
void to the steady flame of the yellow star! Then quietly he had
returned to his self-set task.

With him as teacher, others had learned, and before he was seventy there
were many men who had become true scientists, astronomers. There was
much of the ancient knowledge that these men could not understand, for
the science of a million centuries is not to be learned in a few brief
decades, but they mastered a vast amount of the forgotten lore.

They knew now that the young, live sun, out there in space, was speeding
toward them, their combined velocities equalling more than 100 miles
each second. And they knew that there were not seven, but nine planets
circling about that sun. There were other facts they discovered; they
found that the new sun was far larger than theirs had ever been; indeed,
it was a sun well above average in size and brilliance. There were
planets, a hot sun--a home! Could they get there?

When their ancestors had tried to solve the problem of escape they had
concentrated their work on the problem of going at speeds greater than
that of light. This should be an impossibility, but the fact that the
ancients had tried it, seemed proof enough to their descendants that it
was possible, at least in theory. In the distant past they had needed
speeds exceeding that of light, for they must travel light years; but
now this sun was coming toward them, and already was less than two
hundred and fifty billion miles away!

They would pass that other star in about seventy years. That was
scarcely more than a third of a man's lifetime. They could make the
journey with conceivable speeds--but in that brief period they must
prepare to move!

The swift agitation for action had met with terrific resistance. They
were satisfied; why move?

But, while some men had devoted their time to arousing the people to
help, others had begun doing work that had not been done for a long,
long time. The laboratories were reopened, and workshops began humming
again. They were making things that were new once more, not merely
copying old designs.

Their search had been divided into sections, search for weapons with
which to defend themselves in case they were attacked, and search for
the basic principles underlying the operation of their space ships. They
had machines which they could imitate, but they did not understand them.
Success had been theirs on these quests. The third section had been less
successful. They had also been searching for secrets of the apparatus
their forefathers had used to swing the planets in their orbits, to move
worlds about at will. They had wanted to be able to take not only their
space ships, but their planets as well, when they went to settle on
these other worlds and in this other solar system.

But the search for this secret had remained unrewarded. The secret of
the spaceships they learned readily, and Taj Lamor had designed these
mighty ships below there with that knowledge. Their search for weapons
had been satisfied; they had found one weapon, one of the deadliest that
their ancestors had ever invented. But the one secret in which they were
most interested, the mighty force barrage that could swing a world in
its flight through space, was lost. They could not find it.

They knew the principles of the driving apparatus of their ships, and it
would seem but a matter of enlargement to drive a planet as a ship, but
they knew this was impossible; the terrific forces needed would easily
be produced by their apparatus, but there was no way to apply them to a
world. If applied in any spot, the planet would be torn asunder by the
incalculable strain. They must apply the force equally to the entire
planet. Their problem was one of application of power. The rotation of
the planet made it impossible to use a series of driving apparatus, even
could these be anchored, but again the sheer immensity of the task made
it impossible.

Taj Lamor gazed down again at the great ships in the plaza below. Their
mighty bulks seemed to dwarf even the huge buildings about them. Yet
these ships were his--for he had learned their secrets and designed
them, and now he was to command them as they flew out across space in
that flight to the distant star.

He turned briefly to the Elder, Tordos Gar. "Soon we leave," he said, a
faint edge of triumph in his voice. "We will prove that our way is
right."

The old man shook his head. "You will learn--" he began, but Taj Lamor
did not want to hear.

He turned, passed through a doorway, and stepped into a little
torpedo-shaped car that rested on the metal roof behind him. A moment
later the little ship rose, and then slanted smoothly down over the edge
of the roof, straight for the largest of the ships below. This was the
flagship. Nearly a hundred feet greater was its diameter, and its mile
and a quarter length of gleaming metal hull gave it nearly three hundred
feet greater length than that of the ships of the line.

This expedition was an expedition of exploration. They were prepared to
meet any conditions on those other worlds--no atmosphere, no water, no
heat, or even an atmosphere of poisonous gases they could rectify, for
their transmutation apparatus would permit them to change those gases,
or modify them; they knew well how to supply heat, but they knew too,
that that sun would warm some of its planets sufficiently for their
purposes.

Taj Lamor sent his little machine darting through the great airlock in
the side of the gigantic interstellar ship and lowered it gently to the
floor. A man stepped forward, opened the door for the leader, saluting
him briskly as he stepped out; then the car was run swiftly aside, to be
placed with thousands of others like it. Each of these cars was to be
used by a separate investigator when they reached those other worlds,
and there were men aboard who would use them.

Taj Lamor made his way to a door in the side of a great metal tube that
threaded the length of the huge ship. Opening the door he sat down in
another little car that shot swiftly forward as the double door shut
softly, with a low hiss of escaping air. For moments the car sped
through the tube, then gently it slowed and came to rest opposite
another door. Again came the hissing of gas as the twin doors opened,
and Taj Lamor stepped out, now well up in the nose of the cruiser. As he
stepped out of the car the outer and inner doors closed, and, ready now
for other calls, the car remained at this station. On a ship so long,
some means of communication faster than walking was essential. This
little pneumatic railway was the solution.

As Taj Lamor stepped out of the tube, a half-dozen men, who had been
talking among themselves, snapped quickly to attention. Following the
plans of the long-gone armies of their ancestors, the men of the
expedition had been trained to strict discipline; and Taj Lamor was
their technical leader and the nominal Commander-in-Chief, although
another man, Kornal Sorul, was their actual commander.

Taj Lamor proceeded at once to the Staff Cabin in the very nose of the
great ship. Just above him there was another room, walled on all sides
by that clear, glass-like material, the control cabin. Here the pilot
sat, directing the motions of the mighty ship of space.

Taj Lamor pushed a small button on his desk and in a moment a gray disc
before him glowed dimly, then flashed into life and full, natural color.
As though looking through a glass porthole, Taj Lamor saw the interior
of the Communications Room. The Communications Officer was gazing at a
similar disc in which Taj Lamor's features appeared.

"Have they reported from Ohmur, Lorsand, and Throlus, yet, Morlus Tal?"
asked the commander.

"They are reporting now, Taj Lamor, and we will be ready within two and
one half minutes. The plans are as before; we are to proceed directly
toward the Yellow Star, meeting at Point 71?"

"The plans are as before. Start when ready."

The disc faded, the colors died, and it was gray again. Taj Lamor pulled
another small lever on the panel before him, and the disc changed,
glowed, and was steady; and now he saw the preparations for departure,
as from an eye on the top of the great ship. Men streamed swiftly in
ordered columns all about and into the huge vessels. In an incredibly
short time they were in, and the great doors closed behind them.
Suddenly there came a low, dull hum through the disc, and the sound
mounted quickly, till all the world seemed humming to that dull note.
The warning!

Abruptly the city around him seemed to blaze in a riot of colored light!
The mighty towering bulks of the huge metal buildings were polished and
bright, and now, as the millions of lights, every color of the spectrum,
flashed over all the city from small machines in the air, on the ground,
in windows, their great metal walls glistening with a riot of flowing
color. Then there was a trembling through all the frame of the mighty
ship. In a moment it was gone, and the titanic mass of glistening metal
rose smoothly, quickly to the great roof of their world above them. On
an even keel it climbed straight up, then suddenly it leaped forward
like some great bird of prey sighting its victim. The ground beneath
sped swiftly away, and behind it there came a long line of ships,
quickly finding their position in the formation. They were heading
toward the giant airlock that would let them out into space. There was
but one lock large enough to permit so huge a ship to pass out, and they
must circle half their world to reach it.

On three other worlds there were other giant ships racing thus to meet
beyond their solar system. There were fifty ships coming from each
planet; two hundred mighty ships in all made up this Armada of Space,
two hundred gargantuan interstellar cruisers.

One by one the giant ships passed through the airlock and out into
space. Here they quickly reformed as they moved off together, each ship
falling into its place in the mighty cone formation, with the flagship
of Taj Lamor at the head. On they rushed through space, their speed ever
mounting. Suddenly there seemed to leap out of nowhere another mass of
shining machines that flew swiftly beside them. Like some strange,
shining ghosts, these ships seemed to materialize instantly beside and
behind their fleet. They fell in quickly in their allotted position
behind the Flagship's squadron. One--two more fleets appeared thus
suddenly in the dark, and together the ships were flashing on through
space to their goal of glowing fire ahead!

Hour after hour, day after day the ships flashed on through the awful
void, the utter silence relieved by the communications between
themselves and the slowly weakening communications from the far-off home
planets.

But as those signals from home grew steadily weaker, the sun before them
grew steadily larger. At last the men began to feel the heat of those
rays, to realize the energy that that mighty sea of flame poured forth
into space, and steadily they watched it grow nearer.

Then came a day when they could make out clearly the dim bulk of a
planet before them, and for long hours they slowed down the flying speed
of the ships. They had mapped the system they were approaching; there
were nine planets of varying sizes, some on the near and some on the
far side of the sun. There were but three on the near side; one that
seemed the outermost of the planets, about 35,000 miles in diameter, was
directly in their path, while there were two more much nearer the sun,
about 100,000,000 and 70,000,000 miles distant from it, each about seven
to eight thousand miles in diameter, but they were on opposite sides of
the sun. These more inviting and more accessible worlds were numbers two
and three of the planetary system. It was decided to split the
expedition into two parts; one part was to go to planet two, and the
other to three. Taj Lamor was to lead his group of a hundred ships to
the nearer planet at once.

In a very brief time the great ships slanted down over what seemed to be
a mighty globe of water. They were well in the northern hemisphere, and
they had come near the planet first over a vast stretch of rolling
ocean. The men had looked in wonder at such vast quantities of the
fluid. To them it was a precious liquid, that must be made artificially,
and was to be conserved, yet here they saw such vast quantities of
natural water as seemed impossible. Still, their ancient books had told
of such things, and of other strange things, things that must have been
wondrously beautiful, though they were so old now, these records, that
they were regarded largely as myths.

Yet here were the strange proofs! They saw great masses of fleecy water
vapor, huge billowy things that seemed solid, but were blown lightly in
the wind. And natural air! The atmosphere extended for hundreds of miles
off into space; and now, as they came closer to the surface of this
world the air was dense, and the sky above them was a beautiful blue,
not black, even where there were stars. The great sun, so brilliantly
incandescent when seen from space, and now a glowing globe of
reddish-yellow.

And as they came near land, they looked in wonder at mighty masses of
rock and soil that threw their shaggy heads high above the surrounding
terrain, huge masses that rose high, like waves in the water, till they
towered in solemn grandeur miles into the air! What a sight for these
men of a world so old that age long erosion had washed away the last
traces of hills, and filled in all of the valleys!

In awe they looked down at the mighty rock masses, as they swung low
over the mountains, gazing in wonder at the green masses of the strange
vegetation; strange, indeed, for they for uncounted ages had grown only
mushroom-like cellulose products, and these mainly for ornament, for all
their food was artificially made in huge factories.

Then they came over a little mountain lake, a body of water scarcely
large enough to berth one of their huge ships, but high in the clear air
of the mountains, fed by the melting of eternal snows. It was a
magnificent sapphire in a setting green as emerald, a sparkling lake of
clear water, deep as the sea, high in a cleft in the mountains.

In wonder the men looked down at these strange sights. What a marvelous
home!

Steadily the great machines proceeded, and at last the end of the giant
mountain was reached, and they came to a great plain. But that plain was
strangely marked off with squares, as regularly as though plotted with a
draftsman's square. This world must be inhabited by intelligent beings!

Suddenly Taj Lamor saw strange specks off in the far horizon to the
south, specks that seemed to grow in size with terrific velocity; these
must be ships, the ships of these people, coming to defend their home.
The strangely pallid face of Taj Lamor tightened into lines of grim
resolution. This was a moment he had foreseen and had dreaded. Was he to
withdraw and leave these people unmolested, or was he to stand and fight
for this world, this wonderfully beautiful home, a home that his race
could live in for millions of years to come? He had debated this
question many times before in his mind, and he had decided. There would
never, never be another chance for his people to gain a new home. They
must fight.

Swiftly he gave his orders. If resistance came, if an attack were made,
they were to fight back at once, with every weapon at their disposal.

The strangers' ships had grown swiftly larger to the eye, but still,
though near now, they seemed too small to be dangerous. These giant
interstellar cruisers were certainly invulnerable to ships so small;
their mere size would give them protection! These ships were scarcely as
long as the diameter of the smaller of the interstellar ships--a bare
two hundred and fifty feet for the largest.

The interstellar cruisers halted in their course, and waited for the
little ships to approach. They were fast, for they drew alongside
quickly, and raced to the front of the flagship. There was one small one
that was painted white, and on it there was a large white banner,
flapping in the wind of its passage. The rest of the ships drew off as
this came forward, and stopped, hanging motionless before the control
room of the giant machine. There were men inside--three strange men,
short and oddly pink-skinned--but they were gesturing now, motioning
that the giant machine settle to the ground beneath. Taj Lamor was
considering whether or not to thus parley with the strangers, when
suddenly there leaped from the white craft a beam of clear white--a beam
that was directed toward the ground, then swung up toward the great
cruiser in a swift arc!

As one, a dozen swift beams of pale red flared out from the giant and
bathed the pigmy craft. As they reached it, the white ray that had been
sweeping up suddenly vanished, and for an instant the ship hung poised
in the air; then it began to swing crazily, like the pendulum of a
clock--swung completely over--and with a sickening lurch sped swiftly
for the plain nearly five miles below. In moments there came a brief
flare, then there remained only a little crater in the soft soil.

But the red beams had not stopped with the little ship; they had darted
out to the other machines, trying to reach them before they could bring
those strange white rays into play. The cruisers obviously must win, for
they carried dozens of projectors, but they might be damaged, their
flight delayed. They must defeat those strangers quickly. The rays of
Taj Lamor's ship lashed out swiftly, but almost before they had
started, all the other ships, a full hundred, were in action, and the
flagship was darting swiftly up and away from the battle. Below, those
pale red rays were taking a swift toll of the little ships, and nearly
twenty of them rolled suddenly over, and dashed to destruction far
below.

But now the little ships were in swift darting motion. Because of their
small size, they were able to avoid the rays of the larger interstellar
cruisers, and as their torpedo-shaped hulls flashed about with
bewildering speed, they began to fight back. They had been taken utterly
by surprise, but now they went into action with an abandon and swiftness
that took the initiative away from the gigantic interstellar liners.
They were in a dozen places at once, dodging and twisting, unharmed, out
of the way of the deadly red beams, and were as hard to hit as so many
dancing feathers suspended over an air jet.

And if the pilots were skillful in avoiding enemy rays, their ray men
were as accurate in placing theirs. But then, with a target of such vast
size, not so much skill was necessary.

These smaller vessels were the ships of Earth. The people of the dark
star had entered the solar system quite unannounced, except that they
had been seen in passing the orbit of Mars, for a ship had been out
there in space, moving steadily out toward Neptune, and the great
interstellar cruisers, flashing in across space, away from that frigid
planet, had not seen the tiny wanderer. But he had seen those mighty
hulks, and had sent his message of danger out on the ether, warning the
men of Earth. They had relayed it to Venus, and the ships that had gone
there had received an equally warm reception, and were even now finding
their time fully occupied trying to beat off the Interplanetary Patrol.

The battle ended as swiftly as it began, for Taj Lamor, in his machine
high above, saw that they were outclassed, and ordered them to withdraw
at once. Scarcely ten minutes had elapsed, yet they had lost twenty-two
of their giant ships.

The expedition that had gone to Venus reported a similarly active
greeting. It was decided at once that they should proceed cautiously to
the other planets, to determine which were inhabited and which were not,
and to determine the chemical and physical conditions on each.

The ships formed again out in space, on the other side of the sun,
however, and started at once in compact formation for Mercury.

Their observations were completed without further mishap, and they set
out for their distant home, their number depleted by forty-one ships,
for nineteen had fallen on Venus.




I


The Terrestrian and Venerian governments had met in conference, a grim,
businesslike discussion with few wasted words. Obviously, this was to be
a war of science, a war on a scale never before known on either world.
Agreements were immediately drawn up between the two worlds for a
concerted, cooperative effort. A fleet of new and vastly more powerful
ships must be constructed--but first they must have a complete report on
the huge invading craft that had fallen in western Canada, and on Venus,
for they might conceivably make their secrets their own.

They called for the scientists whose work had made possible their
successful resistance of the marauders: Arcot, Morey and Wade. They
found them working in the Arcot Laboratories.

"Wade," called Arcot tensely as he snapped the switch of the
televisophone, "bring Morey and meet me at the machine on the roof at
once. That was a call from Washington. I'll explain as soon as you get
there."

On the roof Arcot opened the hangar doors, and entered the
five-passenger molecular motion ship inside. Its sleek, streamlined
sides spoke of power and speed. This was a special research model,
designed for their experiments, and carrying mechanisms not found in
commercial crafts. Among these were automatic controls still in the
laboratory stage, but permitting higher speed, for no human being could
control the ship as accurately as these.

It took the trio a little less than a quarter of an hour to make the
5,000 mile trip from New York to the battlefield of Canada. As they sped
through the air, Arcot told them what had transpired. The three were
passed through the lines at once, and they settled to the ground beside
one of the huge ships that lay half buried in the ground. The force of
the impact had splashed the solid soil as a stone will splash soft mud,
and around the ship there was a massive ridge of earth. Arcot looked at
the titanic proportions of this ship from space, and turned to his
friends:

"We can investigate that wreck on foot, but I think it'll be far more
sensible to see what we can do with the car. This monster is certainly a
mile or more long, and we'd spend more time in walking than in
investigation. I suggest, we see if there isn't room for the car inside.
This beats even those huge Kaxorian planes for size." Arcot paused, then
grinned. "I sure would have liked to mix in the fight they must have had
here--nice little things to play with, aren't they?"

"It would make a nice toy," agreed Wade as he looked at the rows of
wicked-looking projectors along the sides of the metal hull, "and I
wonder if there might not be some of the crew alive in there? If there
are, the size of the ship would prevent their showing themselves very
quickly, and since they can't move the ship, it seems to me that they'll
let us know shortly that they're around. Probably, with the engines
stopped, their main weapons are useless, but they would doubtless have
some sort of guns. I'm highly in favor of using the car. We carry a
molecular director ray, so if the way is blocked, we can make a new
one."

Wade's attention was caught by a sudden flare of light a few miles
across the plain. "Look over there--that ship is still flaming--reddish,
but almost colorless. Looks like a gas flame, with a bit of calcium in
it. Almost as if the air in the ship were combustible. If we should do
any exploring in this baby, I suggest we use altitude suits--they can't
do any harm in any case."

Three or four of the great wrecks, spread over a wide area, were burning
now, hurling forth long tongues of colorless, intensely hot flame.
Several of the ships had been only slightly damaged; one had been
brought down by a beam that had torn free the entire tail of the ship,
leaving the bow in good condition. Apparently this machine had not
fallen far; perhaps the pilot had retained partial control of the ship,
his power failing when he was only a comparatively short distance from
Earth. This was rather well to one side of the plain, however, and they
decided to investigate it later.

The ship nearest them had crashed nose first, the point being crushed
and shattered. Arcot maneuvered his craft cautiously toward the great
hole at the nose of the ship, and they entered the mighty vessel slowly,
a powerful spotlight illuminating the interior. Tremendous girders,
twisted and broken by the force of impact, thrust up about them. It soon
became evident that there was little to fear from any living enemies,
and they proceeded more rapidly. Certainly no creature could live after
the shock that had broken these huge girders! Several times metal beams
blocked their path, and they were forced to use the molecular director
ray to bend them out of the way.

"Man," said Arcot as they stopped a moment to clear away a huge member
that was bent across their path, "but those beams do look as if they
were built permanently! I'd hate to ram into one of them! Look at that
one--if that has anywhere near the strength of steel, just think of the
force it took to bend it!"

At last they had penetrated to the long tube that led through the length
of the ship, the communication tube. This admitted the small ship
easily, and they moved swiftly along till they came to what they
believed to be about the center of the invader. Here Arcot proposed that
they step out and see what there was to be seen.

The others agreed, and they at once put on their altitude suits of heavy
rubberized canvas, designed to be worn outside the ship when at high
altitude, or even in space. They were supplied with oxygen tanks that
would keep the wearer alive for about six hours. Unless the atmosphere
remaining in the alien ship was excessively corrosive, they would be
safe. After a brief discussion, they decided that all would go, for if
they met opposition, there would be strength in numbers.

They met their first difficulty in opening the door leading out of the
communication tube. It was an automatic door, and resisted their every
effort--until finally they were forced to tear it out with a ray. It was
impossible to move it in any other way. The door was in what was now the
floor, since the ship seemed to have landed on one side rather than on
its keel.

They let themselves through the narrow opening one at a time, and landed
on the sloping wall of the corridor beyond.

"Lucky this wasn't a big room, or we'd have had a nice drop to the far
wall!" commented Wade. The suits were equipped with a thin vibrating
diaphragm that made speech easy, but Wade's voice came through with a
queerly metallic ring.

Arcot agreed somewhat absently, his attention directed toward their
surroundings. His hand light pierced the blackness, finally halting at a
gaping opening, apparently the entrance to a corridor. As they examined
it, they saw that it slanted steeply downward.

"It seems to be quite a drop," said Wade as he turned his light into it,
"but the surface seems to be rather rough. I think we can do it. I
notice that you brought a rope, Morey; I think it'll help. I'll go
first, unless someone else wants the honor."

"You go first?" Arcot hesitated briefly. "But I don't know--if we're
all going, I guess you had better, at that. It would take two ordinary
men to lower a big bulk like you. On the other hand, if anybody is going
to stay, you're delegated as elevator boy!

"Hold everything," continued Arcot. "I have an idea. I think none of us
will need to hold the weight of the others with the rope. Wade, will you
get three fairly good-sized pieces of metal, something we can tie a rope
to? I think we can get down here without the help of anyone else. Morey,
will you cut the rope in three equal pieces while I help Wade tear loose
that girder?"

Arcot refused to reveal his idea till his preparations were complete,
but worked quickly and efficiently. With the aid of Wade, he soon had
three short members, and taking the rope that Morey had prepared, he
tied lengths of cord to the pieces of metal, leaving twenty foot lengths
hanging from each. Now he carefully tested his handiwork to make sure
the knots would not slip.

"Now, let's see what we can do." Arcot put a small loop in one end of a
cord, thrust his left wrist through this, and grasped the rope firmly
with his hand. Then he drew his ray pistol, and adjusted it carefully
for direction of action. The trigger gave him control over power.
Finally he turned the ray on the block of metal at the other end of the
rope. At once the metal pulled vigorously, drawing the rope taut, and as
Arcot increased the power, he was dragged slowly across the floor.

"Ah--it works." He grinned broadly over his shoulder. "Come on, boys,
hitch your wagon to a star, and we'll go on with the investigation. This
is a new, double action parachute. It lets you down easy, and pulls you
up easier! I think we can go where we want now." After a pause he added,
"I don't have to tell you that too much power will be very bad!"

With Arcot's simple brake, they lowered themselves into the corridor
below, descending one at a time, to avoid any contact with the ray,
since the touch of the beam was fatal.

The scene that lay before them was one of colossal destruction. They had
evidently stumbled upon the engine room. They could not hope to
illuminate its vast expanse with their little hand lights, but they
could gain some idea of its magnitude, and of its original layout. The
floor, now tilted at a steep angle, was torn up in many places, showing
great, massive beams, buckled and twisted like so many wires, while the
heavy floor plates were crumpled like so much foil. Everywhere the room
seemed covered with a film of white silvery metal; it was silver, they
decided after a brief examination, spattered broadcast over the walls of
the room.

Suddenly Morey pointed ceilingward with his light. "That's where the
silver came from!" he exclaimed. A network of heavy bars ran across the
roof, great bars of solid silver fully three feet thick. In one section
gaped a ragged hole, suggesting the work of a disintegration ray, a hole
that went into the metal roof above, one which had plainly been fused,
as had the great silver bars.

Arcot looked in wonder at the heavy metal bars. "Lord--bus bars three
feet thick! What engines they must have! Look at the way those were
blown out! They were short circuited by the crash, just before the
generator went out, and they were volatilized! Some juice!"

With the aid of their improvised elevators, the three men attempted to
explore the tremendous chamber. They had scarcely begun, when Wade
exclaimed:

"Bodies!"

They crowded around his gruesome find and caught their first glimpse of
the invaders from space. Anatomical details could not be distinguished
since the bodies had been caught under a rain of crushing beams, but
they saw that they were not too different from both Terrestrians and
Venerians--though their blood seemed strangely pallid, and their skin
was of a ghastly whiteness. Evidently they had been assembled before an
unfamiliar sort of instrument panel when catastrophe struck; Morey
indicated the dials and keys.

"Nice to know what you're fighting," Arcot observed. "I've a hunch that
we'll see some of these critters alive--but not in this ship!"

They turned away and resumed their examination of the shattered
mechanisms.

A careful examination was impossible; they were wrecks, but Arcot did
see that they seemed mainly to be giant electrical machines of standard
types, though on a gargantuan scale. There were titanic masses of
wrecked metal, iron and silver, for with these men silver seemed to
replace copper, though nothing could replace iron and its magnetic uses.

"They are just electrical machines, I guess," said Arcot at last. "But
what size! Have you seen anything really revolutionary, Wade?"

Wade frowned and answered. "There are just two things that bother me.
Come here." As Arcot jumped over, nearly suspended by his ray pistol,
Wade directed his light on a small machine that had fallen in between
the cracks in the giant mass of broken generators. It was a little
thing, apparently housed in a glass case. There was only one objection
to that assumption. The base of a large generator lay on it, metal fully
two feet thick, and that metal was cracked where it rested on the case,
and the case, made of material an inch and a half thick, was not dented!

"Whewww--that's a nice kind of glass to have!" Morey commented. "I'd
like to have a specimen for examination. Oh--I wonder--yes, it must be!
There's a window in the side up there toward what was the bow that
seemed to me to be the same stuff. It's buried about three feet in solid
earth, so I imagine it must be."

The three made their way at once to where they had seen the window. The
frame appeared to be steel, or some such alloy, and it was twisted and
bent under the blow, for this was evidently the outer wall, and the
impact of landing had flattened the rounded side. But that "glass"
window was quite undisturbed! There was, as a further proof, a large
granite boulder lying against it on the outside--or what had been a
boulder, though it had been shattered by the impact.

"Say--that's some building material!" Arcot indicated the transparent
sheet. "Just look at that granite rock--smashed into sand! Yet the
window isn't even scratched! Look how the frame that held it is
torn--just torn, not broken. I wonder if we can tear it loose
altogether?" He stepped forward, raising his pistol. There was a thud as
his metal bar crashed down when the ray was shut off. Then, as the
others got out of the way, he stepped toward the window and directed his
beam toward it. Gradually he increased the power, till suddenly there
was a rending crash, and they saw only a leaping column of earth and
sand and broken granite flying up through the hole in the steel shell.
There was a sudden violent crash, then a moment later a second equally
violent crash as the window, having flown up to the ceiling, came
thumping back to the floor.

After the dust had settled they came forward, looking for the window.
They found it, somewhat buried by the rubbish, lying off to one side.
Arcot bent down to tilt it and sweep off the dirt; he grasped it with
one hand, and pulled. The window remained where it was. He grasped it
with both hands and pulled harder. The window remained where it was.

"Uh--say, lend a hand will you, Wade." Together the two men pulled, but
without results. That window was about three feet by two feet by one
inch, making the total volume about one-half a cubic foot, but it
certainly was heavy. They could not begin to move it. An equal volume of
lead would have weighed about four hundred pounds, but this was
decidedly more than four hundred pounds. Indeed, the combined strength
of the three men did not do more than rock it.

"Well--it certainly is no kind of matter we know of!" observed Morey.
"Osmium, the heaviest known metal, has a density of twenty-two and a
half, which would weigh about 730 pounds. I think we could lift that, so
this is heavier than anything we know. At least that's proof of a new
system. Between Venus and Earth we have found every element that occurs
in the sun. These people must have come from another star!"

"Either that," returned Arcot, "or proof of an amazing degree of
technological advancement. It's only a guess, of course--but I have an
idea where this kind of matter exists in the solar system. I think you
have already seen it--in the gaseous state. You remember, of course,
that the Kaxorians had great reservoirs for storing light-energy in a
bound state in their giant planes. They had bound light, light held by
the gravitational attraction for itself, after condensing it in their
apparatus, but they had what amounted to a gas--gaseous light. Now
suppose that someone makes a light condenser even more powerful than the
one the Kaxorians used, a condenser that forces the light so close to
itself, increases its density, till the photons hold each other
permanently, and the substance becomes solid. It will be matter, matter
made of light--light matter--and let us call it a metal. You know that
ordinary matter is electricity matter, and electricity matter metals
conduct electricity readily. Now why shouldn't our 'light matter' metal
conduct light? It would be a wonderful substance for windows."

"But now comes the question of moving it," Wade interposed. "We can't
lift it, and we certainly want to examine it. That means we must take it
to the laboratory. I believe we're about through here--the place is
clearly quite permanently demolished. I think we had better return to
the ship and start to that other machine we saw that didn't appear to be
so badly damaged. But--how can we move this?"

"I think a ray may do the trick." Arcot drew his ray pistol, and stepped
back a bit, holding the weapon so the ray would direct the plate
straight up. Slowly he applied the power, and as he gradually increased
it, the plate stirred, then moved into the air.

"It works! Now you can use your pistol, Morey, and direct it toward the
corridor. I'll send it up, and let it fall outside, where we can pick it
up later." Morey stepped forward, and while Arcot held it in the air
with his ray, Morey propelled it slowly with his, till it was directly
under the corridor leading upward. Then Arcot gave a sudden increase in
power, and the plate moved swiftly upward, sailing out of sight. Arcot
shut off his ray, and there came to their ears a sudden crash as the
plate fell to the floor above.

The three men regained their ropes and "double action parachutes" as
Arcot called them, and floated up to the next floor. Again they started
the process of moving the plate. All went well till they came to the
little car itself. They could not use the ray on the car, for fear of
damaging the machinery. They had to use some purely mechanical method of
hoisting it in.

Finally they solved the problem by using the molecular director ray to
swing a heavy beam into the air, then one man pulled on the far end of
it with a rope, and swung it till it was resting on the door of the ship
on one end, and the other rested in a hole they had torn in the lining
of the tube.

Now they maneuvered the heavy plate till it was resting on that beam;
then they released the plate, and watched it slide down the incline,
shooting through the open doorway of the car. In moments the job was
done. The plate at last safely stowed, the three men climbed into the
car, and prepared to leave.

The little machine glided swiftly down the tube through the mighty ship,
finally coming out through the opening that had admitted them. They rose
quickly into the air, and headed for the headquarters of the government
ships.




II


A great number of scientists and military men were already gathered
about the headquarters ship. As Arcot's party arrived, they learned that
each of the wrecks was being assigned to one group. They further learned
that because of their scientific importance, they were to go to the
nearly perfect ship lying off to the west. Two Air Patrolmen were to
accompany them.

"Lieutenant Wright and Lieutenant Greer will go with you," said the
Colonel. "In the event of trouble from possible--though
unlikely--survivors, they may be able to help. Is there anything further
we can do?"

"These men are armed with the standard sidearms, aren't they?" Arcot
asked. "I think we'll all be better off if I arm them with some of the
new director-ray pistols. I have several in my boat. It will be all
right, I suppose?"

"Certainly, Dr. Arcot. They are under your command."

The party, increased to five now, returned to the ship, where Arcot
showed the men the details of the ray pistols, and how to use them. The
control for direction of operation was rather intricate in these early
models, and required considerable explanation. The theoretical range of
even these small hand weapons was infinity in space, but in the
atmosphere the energy was rather rapidly absorbed by ionization of the
air, and the dispersion of the beam made it ineffective in space over a
range of more than thirty-five miles.

Again entering the little molecular motion car, they went at once to the
great hull of the fallen ship. They inspected it cautiously from
overhead before going too close, for the dreadnought, obviously, had
landed without the terrific concussion that the others had experienced,
and there was a possibility that some of the crew had survived the
crash. The entire stern of the huge vessel had been torn off, and
evidently the ship was unable to rise, but there were lights glowing
through the portholes on the side, indicating that power had not failed
completely.

"I think we'd better treat that monster with respect," remarked Wade,
looking down at the lighted windows. "They have power, and the hull is
scarcely dented except where the stern was caught by a beam. It's lucky
we had those ray projector ships! They've been in service only about
four months, haven't they, Lieutenant?"

"Just about that, sir," the Air Patrolman replied. "They hadn't gotten
the hand weapons out in sufficient quantities to be issued to us as
yet."

Morey scowled at the invader. "I don't like this at all. I wonder why
they didn't greet us with some of their beams," he said in worried
tones. It did seem that there should be some of the rays in action now.
They were less than a mile from the fallen giant, and moving rather
slowly.

"I've been puzzled about that myself," commented Arcot, "and I've come
to the conclusion that either the ray projectors are fed by a separate
system of power distribution, which has been destroyed, or that the
creatures from space are all dead."

They were to learn later, in their exploration of the ship, that the
invaders' ray projectors were fed from a separate generator, which
produced a special form of alternating current wave for them. This
generator had been damaged beyond use.

The little machine was well toward the stern of the giant now, and they
lowered it till it was on a level with the torn metal. It was plain that
the ship had been subjected to some terrific tension. The great girders
were stretched and broken, and the huge ribs were bent and twisted. The
central tube, which ran the length of the ship, had been drawn down to
about three quarters of its original diameter, making it necessary for
them to use their ray to enter. In moments their speedster glided into
the dark tunnel. The searchlight reaching ahead filled the metal tunnel
with a myriad deceptive reflections. The tube was lighted up far ahead
of them, and seemed empty. Cautiously they advanced, with Arcot at the
controls.

"Wade--Morey--where will we stop first?" he asked. "The engines? They'll
probably be of prime importance. We know their location. What do you
say?"

"I agree," replied Wade, and Morey nodded his approval.

They ran their craft down the long tube till they reached the door they
knew must be the engine room landing, and stepped out, each wearing an
altitude suit. This ship had landed level, and progress would be much
easier than in the other one. They waited a moment before opening the
door into the engine room, for this led into a narrow corridor where
only one could pass. Caution was definitely in order. The Air Patrolmen
insisted on leading the way. They had been sent along for the express
purpose of protecting the scientists, and it was their duty to lead.
After a brief argument Arcot agreed.

The two officers stepped to the door, and standing off to one side, tore
it open with a ray from their pistols. It fell with a clatter to the
rounded metal floor of the tube, and lay there vibrating noisily, but no
rays of death lanced out from beyond it. Cautiously they peered around
the corner of the long corridor, then seeing nothing, entered. Wade came
next, then Arcot, followed by Morey.

The corridor was approximately thirty feet long, opening into the great
engine room. Already the men could hear the smooth hum of powerful
machines, and could see the rounded backs of vast mechanisms. But there
was no sign of life, human or otherwise. They halted finally at the
threshold of the engine room.

"Well," Arcot said softly. "We haven't seen anyone so far, and I hope no
one has seen us. The invaders may be behind one of those big engines,
quite unaware of us. _If_ they're there, and they see us, they'll be
ready to fight. Now remember, those weapons you have will tear loose
anything they hit, so take it easy. You know something about the power
of those engines, so don't put them out of commission, and have them
splash us all over the landscape.

"But look out for the crew, and get them if they try to get you!"

Cautiously but quickly they stepped out into the great room, forming a
rough half circle, pistols ready for action. They walked forward
stealthily, glancing about them--and simultaneously the enemies caught
sight of each other. There were six of the invaders, each about seven
feet tall, and surprisingly humanoid. They somewhat resembled
Venerians, but they weren't Venerians, for their skin was a strange
gray-white, suggesting raw dough. It seemed to Arcot that these strange,
pale creatures were advancing at a slow walk, and that he stood still
watching them as they slowly raised strange hand weapons. He seemed to
notice every detail: their short, tight-fitting suits of some elastic
material that didn't hamper their movements, and their strange flesh,
which just seemed to escape being transparent. Their eyes were strangely
large, and the black spot of the pupil in their white corneas created an
unnatural effect.

Then abruptly their weapons came up--and Arcot responded with a sudden
flick of his ray, as he flung himself to one side. Simultaneously his
four companions let their beams fly toward the invaders. They glowed
strangely red here, but they were still effective. The six beings were
suddenly gone--but not before they had released their own beams. And
they had taken toll. Lieutenant Wright lay motionless upon the floor.

The Terrestrians scarcely had a chance to notice this, for immediately
there was a terrific rending crash, and clean daylight came pouring in
through a wide opening in the wall of the ship. The five rays had not
stopped on contact with the enemy, but had touched the wall behind them.
An irregular opening now gaped in the smooth metal.

Suddenly there came a second jarring thud, a dull explosion; then a
great sheet of flame filled the hole--a wall of ruddy flame swept
rapidly in. Arcot swung up his ray pistol, pointing it at the mass of
flaming gas. A mighty column of air came through the narrow corridor
from the tube, rushing toward the outside, and taking the flame with it.
A roaring mass of gas hovered outside of the ship.

"Lieutenant," said Arcot, swiftly, "turn your ray on that hole, and keep
it there, blowing that flame outside with it. You'll find you can't put
the fire out, but if you keep it outside the ship, I believe we'll be
reasonably safe." The Patrolman obeyed instantly, relieving Arcot.

Wade and Morey were already bending over the fallen man.

"I'm afraid there's nothing we can do for him," the latter said grimly,
"and every moment here is dangerous. Let's continue our investigation
and carry him back to the ship when we leave." Arcot nodded silently.

Solemnly they turned away from the motionless figure on the floor and
set out on their investigation.

"Arcot," began Morey after a moment, "why is that gas burning like that?
Can't we put it out?"

"Let's get through with this job first," replied Arcot somewhat tersely.
"The discussion comes after."

The bodies of the invaders were gone, so they could not examine them
now. That was a matter for the doctors and biologists, anyway. The
engines were their main interest, huge things which overshadowed
everything about them.

It must have been the concealment afforded by the engines that permitted
three of the enemy to get so close. The only warning the Terrestrians
had was a faint pink haze as they stepped around the corner of an
engine; and a sudden feeling of faintness swept over them. They leaped
back, out of sight, peering around the corner with nerves and muscles
tensed. There was no sign of movement.

As they watched, they saw a pallid hand reaching out with a ray gun; and
Wade swiftly pointed his own weapon. There came a sudden crash of metal,
a groan and quiet. Two other aliens leaped from behind the great engine
just as the Terrestrians dodged further back; as swiftly, they too found
concealment.

Arcot swung his ray up, and was about to pull the trigger that would
send the huge engine toppling over upon them, when he saw that it was
running. He thought of the unknown energies in the machine, the
potential destruction, and he shook his head. Cautiously he looked
around the edge of the towering mass, waiting--his beam flashed out, and
there was a snapping sound as the ray caught a reaching hand and hurled
its owner against a mighty transformer of some sort. For an instant the
huge mass tottered, then was still. In the low concentration of power
that Arcot had used, only a small portion had been touched, and the
molecules of this portion had not been enough to tip over its tremendous
weight.

Only one enemy remained; and Arcot learned swiftly that he was still in
action, for before he could dodge back there came that now-familiar pink
haziness. It touched Arcot's hand, outstretched as it had been when he
fired, and a sudden numbness came over it. His pistol hand seemed to
lose all feeling of warmth or cold. It was there; he could still feel
the weapon's deadened weight. Reflex action hurled him back, his hand
out of range of the ray. In seconds feeling began to return, and in less
than ten his hand was normal again.

He turned to the others with a wry grin. "Whew--that was a narrow
squeak! I must say their ray is a gentlemenly sort of thing. It either
kills you, or doesn't injure you at all. There it goes again!"

A shaft of pink radiance reached the end of the engine, just grazing it,
evidently absorbed by its mass. "Pinning us down," Wade grated. They
certainly couldn't step out into the open space--but they couldn't stay
where they were indefinitely, either. Reinforcements might arrive!

"Look," Wade pointed with his pistol, "he's under that big metal bar--up
there in the roof--see it? I'll pull it down; he may get nervous and
come into sight." Swiftly Arcot sprang forward and caught his arm.

"Lord--don't do that, Wade--there's too much stuff here that we don't
know anything about. Too much chance of your smashing us with him. I'm
going to try to get around to the other side of this machine and see
what I can do, while you fellows keep him occupied."

Arcot disappeared around the black humming giant. Interminably the
others waited for something to happen; then suddenly the beam that had
been playing at irregular intervals across the end of the machine, swung
quickly to the other side; and simultaneously another ray seemed to leap
from the machine itself. They met and crossed. There came a momentary
crashing arc, then both went dead, as the apparatus that generated them
blew out under terrific overload.

The invader evidently carried a spare, for the watchers saw him dart
from concealment, clawing at his pocket pouch. They turned their rays on
him, and just as his projector came free, a ray hurled him violently to
the left. He crashed into a huge motor, and the result was not nice.

The projector had been jerked from his hand and lay off to the side.
Arcot ran to it and picked it up just as they heard the Lieutenant call
an alarmed inquiry.

"I think we're okay now," Arcot answered. "I hope there are no more--but
by all means stay where you are, and use as little power as possible in
blowing that flame outside. It uses up the atmosphere of the ship, and
though we don't need it, I think we'd better take things easy. Call us
if anything looks odd to you."

For several minutes the three scientists looked about them in awe-struck
wonder. They were the first men of Earth to see the driving equipment of
one of the tremendous Kaxorian planes, and they felt tiny beside its
great bulk; but now, as they examined this engine room, they realized
that even the huge plane shrank into insignificance beside this
interstellar cruiser.

All about them loomed the great rounded backs of giant electric
motor-generators of some sort. Across the roof ran a network of gigantic
metal bars, apparently conductors, but so large that they suggested
heavy structural members. The machines they ran into loomed fully thirty
feet into the air; they were longer than cylinders, thirty feet in
diameter, and there was a group of four main machines fully a hundred
twenty feet long! There were many smaller mechanisms--yet these smaller
ones would easily have constituted a complete power supply for the
average big city. Along each wall ran a bank of transformers, cast in
the same heroic mold. These seemed connected with the smaller machines,
there being four conductors leading into each of the minor units, two
intake, and two, apparently, output leads, suggesting rotary converters.
The multiple units and the various types and sizes of transformers made
it obvious that many different frequencies were needed. Some of the
transformers had air cores, and led to machines surrounded with a
silvery white metal instead of the usual iron. These, apparently, were
generating current at an extremely high frequency.

"Well," Morey commented, "they ought to have power enough. But do you
notice that those four main units have their leads radiating in
different directions? The one on the left there seems to lead to that
big power board at the front--or better, bow. I think it would be worth
investigating."

Arcot nodded. "I had the same idea. You notice that two of the main
power units are still working, but that those other two have stopped?
Probably the two dead ones have something to do with the motion of the
ship. But there's one point I think is of even greater interest. All the
machines we have seen, all the conspicuous ones, are secondary power
sources. There are no primary sources visible. Notice that those two
main conduits lead over to the right, and toward the bow. Let's check
where they go to."

As they talked they followed the huge conductors back to their point of
convergence. Suddenly they rounded one of the huge main power units, and
saw before them, at the center of square formed by these machines, a low
platform of transparent light-metal. At the exact center of this
platform, which was twenty feet in diameter, there was a table, about
seven feet across and raised about five feet above the level of the
platform on stout light-metal legs. On the table were two huge cubes of
solid silver, and into these cubes ran all the conductors they had seen.

In the space of about six inches left between the blocks of metal, there
was a small box constructed of some strange new material. It was the
most perfect reflecting surface that any of the men had ever imagined.
Indeed, it was so perfect a reflector that they were unable to see it,
but could detect its presence only by the mirror images, and the fact
that it blotted out objects behind it.

Now they noticed that through the huge blocks of metal there were two
small holes, and two thin wires of this same reflecting material led
into those holes. The wires led directly up to the roof, and, suspended
on three-foot hangers of the light-metal, continued on toward the bow.

Could this be the source of power for the entire ship? It seemed
impossible, yet there were many other seeming impossible things here,
among them that strangely reflecting matter.

There was a low railing about the central platform, apparently intended
to keep observers at a safe distance, so they decided against any more
detailed investigation. As they were about to discuss their unusual
find, the Lieutenant called that he heard sounds behind him.

At once the three ran rapidly toward the narrow corridor that had given
them entrance. The flaming gas was still shooting through the hole in
the wall of the ship, and the rush of air through the corridor made it
difficult to hear any sounds there, and exceedingly difficult to walk.

"Turn on more power, Lieutenant, and see if we can't draw out the
enemy," suggested Arcot, while they braced themselves around the tube
exit.

As the Patrolman increased the power of his beam, the moan of the air
through the corridor increased suddenly to a terrific roar, and a
cyclonic gale swept through. But none of the invaders were drawn out.

After the Lieutenant had shut off the blast from his pistol at Arcot's
signal, the latter said: "I don't think anything less than a war tank
could stand that pressure. It's probable that we'll be attacked if we
stay here much longer, though--and we may not be able to get out at all.
I think, Lieutenant, I'll ask you to stay here while we go out and get
the ship ready to leave." He paused, grinning. "Be sure to keep that
flame outside. You'll be in the position of Hercules after Atlas left
him holding the skies on his shoulders. You can't shut off the ray for
long or we'll have a first-rate explosion. We'll signal when we're ready
by firing a revolver, and you make it to the ship as fast as you can
travel."

Arcot's expression became solemn. "We'll have to carry Wright back to
the ship. He was a brave man, and he certainly deserves burial in the
soil of his own world. And, Morey, we'll have to look up his family.
Your father's company will have to take care of them if they need help."

Slowly the men forced their way back toward their ship, fighting against
the roaring column of air, their burden hindering them somewhat; but at
last they reached the open tunnel. Even here the air was in violent
motion.

They got into their boat as quickly as possible, and set the controls
for reverse flight. Then Wade fired the signal shot. In moments they saw
Lieutenant Greer bucking against the current of air, continuing under
its own momentum.

By the time he was in the ship an ominous calm had fallen. Swiftly they
sped down the corridor, and had almost reached the open air, when
suddenly there was a dull rumble behind them, and they were caught on a
wave of pressure that hurled them along at terrific speed. In a flash
they sped into the open air, the great tunnel with its thick walls and
flared opening acting like a gigantic blunderbus, with the ship as its
bullet. Arcot made no attempt to slow down the little craft, but pressed
his foot heavily on the vertical accelerator. The ship rocketed up with
terrific speed, and the acceleration pinned the men down to their seats
with tripled weight.

Anxiously they watched the huge invader as they sped away from it. At
Arcot's direction Morey signaled the other groups of scientists to get
out of danger with all speed, warning of the impending blow-up. As the
moments sped by the tension mounted. Arcot stared fixedly into the
screen before him, keeping the giant space ship in focus. As they sped
mile upon miles away from it, he began to relax a bit.

Not a word was spoken as they watched and waited. Actually, very little
time passed before the explosion, but to the watchers the seconds
dragged endlessly. Then at twenty-seven miles, the screen flared into a
sheet of blinding white radiance. There was a timeless instant--then a
tremendous wave of sound, a roaring, stunning concussion smote the ship,
shaking it with unrestrained fury--to cease as abruptly as it came.

Immediately they realized the reason. They were rushing away from the
explosion faster than the sound it made, hence could not hear it. After
the first intolerable flash, details became visible. The great ship
seemed to leap into countless tremendous fragments, each rushing away
from the point of the blow-up. They did not go far; the force was not
sustained long enough, nor was it great enough to overcome the inertia
of so vast a mass for more than moments. Huge masses rained to earth, to
bury themselves in the soil.

There came a momentary lull. Then suddenly, from the mass which
evidently held the wrecked engine room, there shot out a beam of intense
white light that swept around in a wide, erratic arc. Whatever it
touched fused instantly into a brilliantly glowing mass of liquid
incandescence. The field itself, fragments of the wreckage, fused and
mingled under its fury. The beam began to swing, faster and faster, as
the support that was holding it melted; then abruptly it turned upon
itself. There came a sudden blast of brilliance to rival that of the
sun--and the entire region became a molten lake. Eyes streaming,
temporarily blinded, the men turned away from the screen.

"That," said Arcot ruefully, "is that! It seems that our visitors don't
want to leave any of their secrets lying around for us to investigate.
I've an idea that all the other wrecks will go like this one did." He
scowled. "You know, we really didn't learn much. Guess we'd better call
the headquarters ship and ask for further instructions. Will you attend
to it, Lieutenant Greer?"




III


Swiftly Arcot's sleek cruiser sped toward New York and the Arcot
Laboratories. They had halted briefly at the headquarters ship of the
Earth-Venus forces to report on their experience; and alone again, the
three scientists were on their way home.

With their course set, Arcot spoke to the others. "Well, fellows, what
are your opinions on--what we've seen? Wade, you're a chemist--tell us
what you think of the explosion of the ship, and of the strange color of
our molecular ray in their air."

Wade shook his head doubtfully. "I've been trying to figure it out, and
I can't quite believe my results. Still, I can't see any other
explanation. That reddish glow looked like hydrogen ions in the air. The
atmosphere was certainly combustible when it met ours, which makes it
impossible for me to believe that their air contained any noticeable
amount of oxygen, for anything above twenty per cent oxygen and the rest
hydrogen would be violently explosive. Apparently the gas had to mix
liberally with our air to reach that proportion. That it didn't explode
when ionized, showed the absence of hydro-oxygen mixture.

"All the observed facts except one seem to point to an atmosphere
composed largely of hydrogen. That one--there are beings living in it! I
can understand how the Venerians might adapt to a different climate, but
I can't see how anything approaching human life can live in an
atmosphere like that."

Arcot nodded. "I have come to similar conclusions. But I don't see too
much objection to the thought of beings living in an atmosphere of
hydrogen. It's all a question of organic chemistry. Remember that our
bodies are just chemical furnaces. We take in fuel and oxidize it, using
the heat as our source of power. The invaders live in an atmosphere of
hydrogen. They eat oxidizing fuels, and breathe a reducing atmosphere;
they have the two fuel components together again, but in a way different
from our method. Evidently, it's just as effective. I'm sure that's the
secret of the whole thing."

"Sounds fairly logical." Wade agreed. "But now I have a question for
you. Where under the sun did these beings come from?"

Arcot's reply came slowly. "I've been wondering the same thing. And the
more I wonder, the less I believe they did come from--under our sun.
Let's eliminate all the solar planets--we can do that at one fell swoop.
It's perfectly obvious that those ships are by no means the first crude
attempts of this race to fly through space. We're dealing with an
advanced technology. If they have had those ships even as far away as
Pluto, we should certainly have heard from them by now.

"Hence, we've got to go out into interstellar space. You'll probably
want to ram some of my arguments down my throat--I know there is no star
near enough for the journey to be made in anything less than a couple of
generations by all that's logical; and they'd freeze in the interstellar
cold doing it. There is no _known_ star close enough--but how about
unknowns?"

"What have they been doing with the star?" Morey snorted. "Hiding it
behind a sun-shade?"

Arcot grinned. "Yes. A shade of old age. You know a sun can't radiate
forever; eventually they die. And a dead sun would be quite black, I'm
sure."

"And the planets that circle about them are apt to become a wee bit cool
too, you know."

"Agreed," said Arcot, "and we wouldn't be able to do much about it. But
give these beings credit for a little higher order of intelligence. We
saw machines in that space ship that certainly are beyond us! They are
undoubtedly heating their planets with the same source of energy with
which they are running their ships.

"I believe I have confirmation of that statement in two things. They are
absolutely colorless; they don't even have an opaque white skin. Any
living creature exposed to the rays of a sun, which is certain to emit
some chemical rays, is subject to coloration as a protection against
those rays. The whites, who have always lived where sunlight is weakest,
have developed a skin only slightly opaque. The Orientals, who live in
more tropical countries, where less clothes and more sun is the motto,
have slightly darker skins. In the extreme tropics Nature has found it
necessary to use a regular blanket of color to stop the rays. Now
extrapolating the other way, were there no such rays, the people would
become a pigmentless race. Since most proteins are rather translucent,
at least when wet, they would appear much as these beings do. Remember,
there are very few colored proteins. Hemoglobin, such as in our blood,
and hemocyanin, like that in the blue blood of the Venerians, are
practically unique in that respect. For hydrogen absorption, I imagine
the blood of these creatures contains a fair proportion of some highly
saturated compound, which readily takes on the element, and gives it up
later.

"But we can kick this around some more in the lab."

Before starting for New York, Arcot had convinced the officer in charge
that it would be wise to destroy the more complete of the invaders'
ships at once, lest one of them manage to escape. The fact that none of
them had any rays in operation was easily explained; they would have
been destroyed by the Patrol if they had made any show of weapons. But
they might be getting some ready, to be used in possible escape
attempts. The scientists were through with their preliminary
investigations. And the dismembered sections would remain for study,
anyway.

The ships had finally been rayed apart, and when the three had left,
their burning atmosphere had been sending mighty tongues of flame a mile
or more into the air. The light gas of the alien atmosphere tended to
rise in a great globular cloud, a ball that quickly burned itself out.
It had not taken long for the last of the machines to disintegrate under
the rays. There would be no more trouble from them, at any rate!

Now Morey asked Arcot if he thought that they had learned all they could
from the ships; would it not have been wiser to save them, and
investigate more fully later, taking a chance on stopping any sudden
attack by surviving marauders by keeping a patrol of Air Guards there.

To which Arcot replied, "I thought quite a bit before I suggested their
destruction, and I conferred for a few moments with Forsyth, who's just
about tops in biology and bacteriology. He said that they had by no
means learned as much as they wished to, but they'd been forced to leave
in any event. Remember that pure hydrogen, the atmosphere we were
actually living in while on the ship, is quite as inert as pure
oxygen--when alone. But the two get very rough when mixed together. The
longer those ships lay there the more dangerously explosive they became.
If we hadn't destroyed them, they would have wrecked themselves. I still
think we followed the only logical course.

"Dr. Forsyth mentioned the danger of disease. There's a remote
possibility that we might be susceptible to their germs. I don't believe
we would be, for our chemical constitution is so vastly different. For
instance, the Venerians and Terrestrians can visit each other with
perfect freedom. The Venerians have diseases, and so do we, of course;
but there are things in the blood of Venerians that are absolutely
deadly to any Terrestrian organism. We have a similar deadly effect on
Venerian germs. It isn't immunity--it's simply that our respective
constitutions are so different that we don't need immunity. Similarly,
Forsyth thinks we would be completely resistant to all diseases brought
by the invaders. However, it's safer to remove the danger, if any,
first, and check afterward."

The three men sped rapidly back to New York, flying nearly sixty miles
above the surface of the Earth, where there would be no interfering
traffic, till at length they were above the big city, and dropping
swiftly in a vertical traffic lane.

Shortly thereafter they settled lightly in the landing cradle at the
Arcot Laboratories. Arcot's father, and Morey's, were there, anxiously
awaiting their return. The elder Arcot had for many years held the
reputation of being the nation's greatest physicist, but recently he had
lost it--to his son. Morey Senior was the president and chief
stockholder in the Transcontinental Air Lines. The Arcots, father and
son, had turned all their inventions over to their close friends, the
Moreys. For many years the success of the great air lines had been
dependent in large part on the inventions of the Arcots; these new
discoveries enabled them to keep one step ahead of competition, and as
they also made the huge transport machines for other companies, they
drew tremendous profits from these mechanisms. The mutual interest,
which had begun as a purely financial relationship, had long since
become a close personal friendship.

As Arcot stepped from his speedster, he called immediately to his
father, telling of their find, the light-matter plate.

"I'll need a handling machine to move it. I'll be right back." He ran to
the elevator and dropped quickly to the heavy machinery lab on the lower
floor. In a short time he returned with a tractor-like machine equipped
with a small derrick, designed to get its power from the electric mains.
He ran the machine over to the ship. The others looked up as they heard
the rumble and hum of its powerful motor. From the crane dangled a
strong electro-magnet.

"What's that for?" asked Wade, pointing to the magnet. "You don't expect
this to be magnetic, do you?"

"Wait and see!" laughed Arcot, maneuvering the handling machine into
position. One of the others made contact with the power line, and the
crane reached into the ship, lowering the magnet to the plate of
crystal. Then Arcot turned the power into the lifting motor. The hum
rose swiftly in volume and pitch till the full load began to strain the
cables. The motor whined with full power, the cables vibrating under the
tension. The machine pulled steadily, until, to Arcot's surprise, the
rear end of the machine rose abruptly from the floor, tipping forward.

"Well--it _was_ magnetic, but how did you know?" asked the surprised
Wade. Since the ship was made of the Venerian metal, coronium, which was
only slightly magnetic, the plate was obviously the magnet's only load.

"Never mind. I'll tell you later. Get an I-beam, say about twenty feet
long, and see if you can't help lift that crazy mass. I think we ought
to manage it that way."

And so it proved. With two of them straddling the I-beam, the leverage
was great enough to pull the plate out. Running it over to the elevator,
they lowered the heavy mass, disconnected the cable, and rode down to
Arcot's laboratory. Again the I-beam and handling machine were brought
into play, and the plate was unloaded from the car. The five men
gathered around the amazing souvenir from another world.

"I'm with Wade in wondering how you knew the plate was magnetic, son,"
commented the elder Arcot. "I can accept your explanation that the stuff
is a kind of matter made of light, but I know you too well to think it
was just a lucky guess. How did you know?"

"It really was pretty much of a guess, Dad, though there was some logic
behind the thought. You ought to be able to trace down the idea! How
about you, Morey?" Arcot smiled at his friend.

"I've kept discreetly quiet," replied Morey, "feeling that in silence I
could not betray my ignorance, but since you ask me, I can guess too. I
seem to recall that light is affected by a powerful magnet, and I can
imagine that that was the basis for your guess. It has been known for
many years, as far back as Clerk Maxwell, that polarized light can be
rotated by a powerful magnet."

"That's it! And now we may as well go over the whole story, and tell Dad
and your father all that happened. Perhaps in the telling, we can
straighten out our own ideas a bit."

For the next hour the three men talked, each telling his story, and
trying to explain the whys and wherefores of what he had seen. In the
end all agreed on one point: if they were to fight this enemy, they
_must_ have ships that could travel though space with speed to match
that of the invaders, ships with a self-contained source of power.

During a brief lull in the conversation, Morey commented rather
sarcastically: "I wonder if Arcot will now kindly explain his famous
invisible light, or the lost star?" He was a bit nettled by his own
failure to remember that a star could go black. "I can't see what
connection this has with their sudden attack. If they were there, they
must have developed when the star was bright, and as a star requires
millions of years to cool down, I can't see how they could suddenly
appear in space."

Before answering, Arcot reached into a drawer of his desk and pulled out
an old blackened briar pipe. Methodically he filled it, a thoughtful
frown on his face; then carefully lighting it, he leaned back, puffing
out a thin column of gray smoke.

"Those creatures must have developed on their planets before the sun
cooled." He puffed slowly. "They are, then, a race millions of years
old--or so I believe. I can't give any scientific reason for this
feeling; it's merely a hunch. I just have a feeling that the invaders
are old, older than our very planet! This little globe is just about two
billion years old. I feel that that race is so very ancient they may
well have counted the revolutions of our galaxy as, once every twenty or
thirty million years, it swung about its center.

"When I looked at those great machines, and those comparatively little
beings as they handled their projectors, they seemed out of place. Why?"
He shrugged. "Again, just a hunch, an impression." He paused again, and
the slow smoke drifted upward.

"If I'm granted the premise that a black, dead star is approaching the
Solar System, then my theorizing may seem more logical. You agree?" The
listeners nodded and Arcot continued. "Well--I had an idea--and when I
went downstairs for the handling machine, I called the Lunar
Observatory." He couldn't quite keep a note of triumph out of his voice.
"Gentlemen--some of the planets have been misbehaving! The outermost
planets, and even some of those closer to the sun have not been moving
as they should. A celestial body of appreciable mass _is_ approaching
the System; though thus far nothing has been seen of the visitor!"

A hubbub of excited comment followed this startling revelation. Arcot
quieted them with an upraised hand. "The only reason you and the world
at large haven't heard about this as yet is the fact that the
perturbation of the planets is so very slight that the astronomers
figured they might have made an error in calculation. They're
rechecking now for mistakes.

"To get back to my visualization--It must have been many millions of
years ago that life developed on the planets of the black star, a warm
sun then, for it was much younger. It was probably rather dim as suns go
even its younger days. Remember, our own sun is well above average in
brilliance and heat radiation.

"In those long-gone ages I can imagine a race much like ours developing,
differing chemically, in their atmosphere of hydrogen; but the chemical
body is not what makes the race, it's the thought process. They must
have developed, and then as their science grew, their sun waned. Dimmer
and dimmer it became, until their planets could not maintain life
naturally. Then they had to heat them artificially. There is no question
as to their source of power; they had to use the energy of matter--so
called atomic energy--for no other source would be great enough to do
what had to be done. It is probable that their science had developed
this long before their great need arose.

"With this must also have come the process of transmutation, and the
process they use in driving their interstellar cruisers. I am sure those
machines are driven by material energy.

"But at last their star was black, a closed star, and their cold, black
planets must circle a hot, black sun forever! They were trapped for
eternity unless they found a way to escape to some other stellar system.
They could not travel as fast as light, and they could escape only if
they found some near-by solar system. Their star was dead--black. Let's
call it Nigra--the Black One--since like every other star it should have
a name. Any objection?"

There was none, so Arcot continued:

"Now we come to an impossibly rare coincidence. That two suns in their
motion should approach each other is beyond the point of logic. That
both suns have a retinue of planets approaches the height of the
ridiculous. Yet that is what is happening right now. And the Nigrans--if
that's the correct term--have every intention of taking advantage of
the coincidence. Since our sun has been visible to them for a long, long
time, and the approaching proximity of the suns evident, they had lots
of time to prepare.

"I believe this expedition was just an exploratory one; and if they can
send such huge machines and so many of them, for mere exploration, I'm
sure they must have quite a fleet to fight with.

"We know little about their weapons. They have that death ray, but it's
not quite as deadly as we might have feared, solely because our ships
could outmaneuver them. Next time, logically, they'll bring with them a
fleet of little ships, carried in the bellies of those giants, and
they'll be a real enemy. We'll have to anticipate their moves and build
to circumvent them.

"As for their ray, I believe I have an idea how it works. You're all
familiar with the catalytic effects of light. Hydrogen and chlorine will
stand very peacefully in the same jar for a long time, but let a strong
light fall on them, and they combine with terrific violence. This is the
catalytic effect of a vibration, a wave motion. Then there is such a
thing as negative catalysis. In a certain reaction, if a third element
or compound is introduced, all reaction is stopped. I believe that's the
principle of the Nigran death ray; it's a catalyst that simply stops the
chemical reactions of a living body, and these are so delicately
balanced that the least resistance will upset them."

Arcot halted, and sat puffing furiously for a moment. During his
discourse the pipe had died to an ember; with vigorous puffing he tried
to restore it. At last he had it going and continued.

"What other weapons they have we cannot say. The secret of invisibility
must be very old to them. But we'll guard against the possibility by
equipping our ships against it. The only reason the patrol ships aren't
equipped already is that invisibility is useless with modern criminals;
they all know the secret and how to fight it."

Morey interrupted with a question.

"Arcot, it's obvious that we have to get out into space to meet the
enemy--and we'll have to have freedom of movement there. How are we
going to do it? I was wondering if we could use Wade's system of storing
the atomic hydrogen in solution. That yields about 100,000 calories for
every two grams, and since this is a method of storing heat energy, and
your molecular motion director is a method of converting heat into
mechanical work with 100 per cent efficiency, why not use that? All we
need, really, is a method of storing heat energy for use while we're in
space."

Arcot exhaled slowly before answering, watching the column of smoke
vanish into the air.

"I thought of that, and I've been trying to think of other, and if
possible, better, cheaper, and quicker ways of getting the necessary
power.

"Let's eliminate the known sources one by one. The usual ones, the ones
men have been using for centuries, go out at once. The atomic hydrogen
reaction stores more energy per gram than any other chemical reaction
known. Such things as the storage battery, the electro-static condenser,
the induction coil, or plain heat storage, are worthless to us. The only
other method of storing energy we know of is the method used by the
Kaxorians in driving their huge planes.

"They use condensed light-energy. This is efficient to the ultimate
maximum, something no other method can hope to attain. Yet they need
huge reservoirs to store it. The result is still ineffective for our
purpose; we want something we can put in a small space; we want to
condense the light still further. That will be the ideal form of energy
storage, for then we will be able to release it directly as a heat ray,
and so use it with utmost efficiency. I think we can absorb the released
energy in the usual cavity radiator."

A queer little smile appeared on Arcot's face. "Remember--what we want
is light in a more condensed form, a form that is naturally stable, and
that does not need to be held in a bound state, but actually requires
urging to bring about the release of energy. For example--"

A shout from Wade interrupted him. "That's really rare! _Whoo_--I have
to hand it to you! That takes all the prizes!" He laughed delightedly.
In puzzled wonder Morey and the two older men looked at him, and at
Arcot who was grinning broadly now.

"Well, I suppose it must be funny," Morey began, then hesitated. "Oh--I
see--say, that _is_ good!" He turned to his father. "I see now what he's
been driving at. It's been right here under our noses all the time.

"The light-matter windows we found in the wrecked enemy ships contain
enough bound light-energy to run all the planes we could make in the
next ten years! We're going to have the enemy supply us with power we
can't get in any other way. I can't decide, Arcot, whether you deserve a
prize for ingenuity, or whether we should receive booby-prizes for our
stupidity."

Arcot Senior smiled at first, then looked dubiously at his son.

"There's definitely plenty of the right kind of energy stored there--but
as you suggested, the energy will need encouragement to break free. Any
ideas?"

"A couple. I don't know how they'll work, of course; but we can try."
Arcot puffed at his pipe, serious now as he thought of the problems
ahead.

Wade interposed a question. "How do you suppose they condense that light
energy in the first place, and, their sun being dead, whence all the
light? Back to the atom, I suppose."

"You know as much as I do, of course, but I'm sure they must break up
matter for its energy. As for the condensation problem, I think I have a
possible solution of that too--it's the key to the problem of release.
There's a lot we don't know now--but we'll have a bigger store of
knowledge before this war is over--if we have anything at all!" he added
grimly. "It's possible that man may lose knowledge, life, his planets
and sun--but there's still plenty of hope. We're not finished yet."

"How do you think they got their energy loose?" asked

Wade. "Do you think those big blocks of what appeared to be silver were
involved in the energy release?"

"Yes, I do. Those blocks were probably designed to carry away the power
once it was released. How the release was accomplished, though, I don't
know. They couldn't use material apparatus to start their release of
material energy; the material of the apparatus might 'catch fire' too.
They had to have the disintegrating matter held apart from all other
matter. This was quite impossible, if you are going to get the energy
away by any method other than by the use of fields of force. I don't
think that is the method. My guess is that a terrific current of
electricity would accomplish it if anything would.

"How then are we going to get the current to it? The wires will be
subject to the same currents. Whatever they do to the matter involved,
the currents will do to the apparatus--except in one case. If that
apparatus is made of _some other kind of matter_, then it wouldn't be
affected. The solution is obvious. Use some of the light-matter. What
will destroy light-matter, won't destroy electricity-matter, and what
will destroy electricity-matter, won't disturb light-matter.

"Do you remember the platform of light-metal, clear as crystal? It must
have been an insulating platform. What we started as our assumptions in
the case of the light-metal, we can now carry further. We said that
electricity-metals carried electricity, so light-metals would carry or
conduct light. Now we know that there is no substance which is
transparent to light, that will carry electricity by metallic
conduction. I mean, of course, that there is no substance transparent to
light, and at the same time capable of carrying electricity by
electronic transmission. True, we have things like NaCl solutions in
ordinary H_{2}O which will carry electricity, but here it's ionic
conduction. Even glass will carry electricity very well when hot; when
red hot, glass will carry enough electricity to melt it very quickly.
But again, glass is not a solid, but a viscous liquid, and it is again
carried by ionic conduction. Iron, copper, sodium, silver, lead--all
metals carry the current by means of electron drift through the solid
material. In such cases we can see that no transparent substance
conducts electricity.

"Similarly, the reverse is true. No substance capable of carrying
electricity by metallic conduction is transparent. All are opaque, if in
any thickness. Of course, gold is transparent when in leaf form--but
when it's that thin it won't conduct very much! The peculiar condition
we reach in the case of the invisible ship is different. There the
effects are brought about by the high frequency impressed. But you get
my point.

"Do you remember those wires that we saw leading to that little box of
the reflecting material? So perfectly reflecting it was that we didn't
see it. We only saw where it must be; we saw the light it reflected.
That was no doubt light-matter, a non-metal, and as such, non-conductive
to light. Like sulphur, an electric non-metal, it reflected the base of
which it was formed. Sulphur reflects the base of which it was formed.
Sulphur reflects electricity and--in the crystalline form--passes light.
This light-non-metal did the same sort of thing; it reflected light and
passed electricity. It was a conductor.

"Now we have the things we need, the matter to disintegrate, and the
matter to hold the disintegrating material in. We have two different
types of matter. The rest is obvious--but decidedly not easy. They have
done it, though; and after the war is over, there should be many of
their machines drifting about in space waiting to give up their
secrets."

Arcot Senior clapped his son on the back. "A fair foundation on which to
start, anyway. But I think it's time now that you got working on your
problem; and since I'm officially retired, I'm going downstairs. You
know I'm working in my lab on a method to increase the range and power
of your projector for the molecular motion field. Young Norris is
helping me, and he really has ideas. I'll show you our math later."

The party broke up, the three younger men staying in their own labs, the
older men leaving.




IV


The three immediately set to work. At Arcot's suggestion, Wade and Morey
attacked the plate of crystal in an attempt to tear off a small piece,
on which they might work. Arcot himself went into the televisophone room
and put through a second call to the Tychos Observatory, the great
observatory that had so recently been established on the frigid surface
of the Moon. The huge mirror, twenty feet in diameter, allowed an
immense magnification, and stellar observations were greatly
facilitated, for no one bothered them, and the "seeing" was always
perfect.

However, the great distance was rather a handicap to the ordinary
televisophone stations, and all calls put through to the astronomers had
to be made through the powerful sending station in St. Louis, where all
interplanetary messages were sent and received, while that side of the
Earth was facing the station; and from Constantinople, when that city
faced the satellite. These stations could bridge the distance readily
and clearly.

For several minutes Arcot waited while connections were being made with
the Moon; then for many more minutes he talked earnestly with the
observer in this distant station, and at last satisfied, he hung up.

He had outlined his ideas concerning the black star, based upon the
perturbation of the planets; then he had asked them to investigate the
possibilities, and see if they could find any blotting out of stars by a
lightless mass.

Finally he returned to Morey and Wade who had been working on the
crystal plate. Wade had an expression of exasperation on his face, and
Morey was grinning broadly.

"Hello, Arcot--you missed all the fun! You should have seen Wade's
struggle with that plate!" The plate, during his absence, had been
twisted and bent, showing that it had undergone some terrific stresses.
Now Wade began to make a series of highly forceful comments about the
properties of the plate in language that was not exactly scientific. It
had value, though, in that it seemed to relieve his pent-up wrath.

"Why, Wade, you don't seem to like that stuff. Maybe the difficulty lies
in your treatment, rather than in the material itself. What have you
tried?"

"Everything! I took a coronium hack saw that will eat through molybdenum
steel like so much cheese, and it just wore its teeth off. I tried some
of those diamond rotary saws you have, attached to an electric motor,
and it wore out the diamonds. That got my goat, so I tried using a
little force. I put it in the tension testing machine, and clamped
it--the clamp was good for 10,000,000 pounds--but it began to bend, so I
had to quit. Then Morey held it with a molecular beam, and I tried
twisting it. Believe me, it gave me real pleasure to see that thing
yield under the pressure. But it's not brittle; it merely bends.

"And I can't cut it, or even get some shavings off the darned thing. You
said you wanted to make a Jolly balance determination of the specific
gravity, but the stuff is so dense you'd need only a tiny scrap--and I
can't break it loose!" Wade looked at the plate in thorough disgust.

Arcot smiled sympathetically; he could understand his feelings, for the
stuff certainly was stubborn. "I'm sorry I didn't warn you fellows about
what you'd run into, but I was so anxious to get that call through to
the Moon that I forgot to tell you how I expected to make it workable.
Now, Wade, if you'll get another of those diamond-tooth rotary saws,
I'll get something that may help. Put the saw on the air motor. Use the
one made of coronium."

Wade looked after the rapidly disappearing Arcot with raised eyebrows,
then, scratching his head, he turned and did as Arcot had asked.

Arcot returned in about five minutes with a small handling machine, and
a huge magnet. It must have weighed nearly half a ton. This he quickly
connected to the heavy duty power lines of the lab. Now, running the
handling machine into position, he quickly hoisted the bent and twisted
plate to the poles of the magnet, with the aid of the derrick. Then
backing the handling machine out of the way, he returned briskly to his
waiting associates.

"Now we'll see what we will see!" With a confident smile Arcot switched
on the current of the big magnet. At once a terrific magnetic flux was
set up through the light-metal. He took the little compressed-air saw,
and applied it to the crystal plate. The smooth hiss of the air deepened
to a harsh whine as the load came on it, then the saw made contact with
the refractory plate.

Unbelievingly Wade saw the little diamond-edge saw bite its way slowly
but steadily into the plate. In a moment it had cut off a little corner
of the light-matter, and this fell with a heavy thud to the magnet pole,
drawn down by the attraction of the magnet and by gravity.

Shutting off the magnet, Arcot picked up a pair of pliers and gripped
the little fragment.

"Whew--light-metal certainly isn't light metal! I'll bet this little
scrap weights ten pounds! We'll have to reduce it considerably before we
can use it. But that shouldn't be too difficult."

By using the magnet and several large diamond faceplates they were able
to work the tough material down to a thin sheet; then with a heavy
press, they cut some very small fragments, and with these, determined
the specific gravity.

"Arcot," Wade asked finally, "just how does the magnet make that stuff
tractable? I'm not physicist enough to figure out what takes place
inside the material."

"Magnetism worked as it did," Arcot explained, "because in this
light-matter every photon is affected by the magnetism, and every photon
is given a new motion. That stuff can be made to go with the speed of
light, you know. It's the only solid that could be so affected. This
stuff should be able, with the aid of a molecular motion beam, which
will make all the photons move in parallel paths, to move at the full
speed of each photon--186,000 miles a second. The tremendous speed of
these individual photons is what makes the material so hard. Their
kinetic impulse is rather considerable! It's the kinetic blow that the
molecules of a metal give that keeps other metal from penetrating it.
This simply gives such powerful impulse that even diamonds wouldn't cut
it.

"You know that an iron saw will cut platinum readily, yet if both are
heated to say, 1600 degrees, the iron is a liquid, and the platinum very
soft--but now the platinum cuts through the iron!

"Heat probably won't have any effect on this stuff, but the action of
the magnet on the individual photons corresponds to the effect of the
heat on the individual atoms and molecules. The mass is softened, and we
can work it. At least, that's the way I figure it out.

"But now, Wade, I wish you'd see if you can determine the density of the
stuff. You're more used to those determinations and that type of
manipulation than we are. When you get through, we may be able to show
you some interesting results ourselves!"

Wade picked up a tiny chip of the light-metal and headed for his own
laboratory. Here he set up his Jolly balance, and began to work on the
fragment. His results were so amazing that he checked and rechecked his
work, but always with the same answer. Finally he returned to the main
lab where Arcot and Morey were busy at the construction of a large and
complicated electro-static apparatus.

"What did you find?" called out Arcot, as he saw Wade reenter the room.
"Hold your report a second and give us a hand here, will you? I have a
laboratory scale apparatus of the type the Kaxorians used in the storage
of light. They've known, ever since they began working with them, that
their machines would release the energy with more than normal violence,
if certain changes were made in them. That is, the light condenser, the
device that stored the photons so close to each other, would also serve
to urge them apart. I've made the necessary changes, and now I'm trying
to set up the apparatus to work on solid light-matter. It was developed
for gaseous material, and it's a rather tricky thing to change it over.
But I think we've almost got it.

"Wade, will you connect that to the high frequency oscillator
there--no--through that counterbalanced condenser. We may have to change
the oscillator frequency quite a bit, but a variable condenser will do
that.

"Now, what results did you get?"

Wade shook his head doubtfully. "We all know it's amazing stuff--and of
course, it must be heavy--but still--well, anyway, I got a density of
103.5!"

"Whewww--103.5! Lord! That's almost five times as heavy as the heaviest
metal hitherto known. There's about half a cubic foot of the material;
that would mean about 4000 pounds for the whole mass, or two tons. No
wonder we couldn't lift the plate!"

They stopped their work on the Kaxorian apparatus to discuss the amazing
results of the density test, but now they fell to again, rapidly
assembling the device, for each was a trained experimenter. With all but
the final details completed, Arcot stood back and surveyed their
handiwork.

"I think we'll have enough urge to cause disintegration right here," he
said, "but I want to make sure, and so, before we set up the case over
it, I think we may as well put that big magnet in place, and have it
there to help in the work of disintegration, if need be."

At last the complete apparatus was set up, and the tiny bit of
light-matter they were to work on was placed on the table of a powerful
Atchinson projector microscope, the field of view being in the exact
center of the field of both the magnet and the coil. Carefully, then,
step by step, Arcot, Morey and Wade went over their work, checking and
rechecking.

"Well, we're ready," said Arcot finally, as he placed the projector
screen in position and dimmed the lights in the room. A touch of the
switch, and the projection screen was illuminated with the greatly
enlarged image of the tiny scrap of light-metal.

With his hand on the switch, Arcot spoke to the other two. "I won't say
there's _no_ danger, since we haven't done this before; and if all the
energy should be released at once, it'll blow the top out of the
building. But I'm reasonably sure that it will work safely. Any
objections?"

Wade shook his head, and Morey said: "I can't see any flaws in our
work."

Arcot nodded, and unconsciously tensing, he closed the switch. This put
the powerful Arcot oscillator tubes into action, and the power was ready
for application.

Slowly he closed the rheostat and put the power into the coil. The
little sliver of metal on the slide seemed to throb a bit, and its
outline grew hazy; but at last, with full power on, the release was so
slow as to be imperceptible.

"Guess we need the magnet after all; I'll put it on this time."

He opened the coil circuit and closed the magnet circuit at half
voltage, then again he increased the current through the rheostat. This
time the plate throbbed quite violently, it took the appearance of a bit
of iodine. Dense vapors began pouring from it, and instantly those
vapors became a blindingly brilliant flood of light. Arcot had snapped
open the switch the moment he saw this display start, and it had had
little time to act, for the instant the circuit was opened, it subsided.
But even in that brief time, the light aluminum screen had suddenly
become limp and slumped down, molten! The room was unbearably hot, and
the men were half blinded by the intensity of the light.

"It works!" yelled Wade. "It works! That sure was hot, too--it's
roasting in here." He flung open a window. "Let's have some air."

Arcot and Morey gripped hands with a broad grin. That display meant that
Earth and Venus would have space ships with which to fight space ships.
Reason enough for their joy.

Though they had made an unusual amount of progress already, there was
still a great deal of development work to be done. Fuller was needed,
Arcot decided, so he called the elder Morey and requested his services
if he could be spared from his present work. He could, and would arrive
later that day.

When Fuller appeared about mid-afternoon, he found the three friends
already at work on the development of a more compact apparatus than the
makeshift hookup used in making that first release mechanism.

"And so you can see," said Arcot as he finished his summary of their
work to that point, "we still have quite a job ahead of us. I'm now
trying to find some data for you to work on, but I can tell you this:
We'll need a ship that has plenty of strength and plenty of speed. There
will be the usual power plant, of course; the generators, the power-tube
board, and the electro-magnetic relays for the regular molecular motion
controls. Then, in addition, we must have controls for the ray
projector, though that must wait a while, for Dad is working on a method
of doubling our range.... Oh yes, the driving units will be inside the
ship now, for all our power will come from the energy of the
light-matter."

They spent the next hour in discussing the manifold details involved in
the design of their space ship: the mechanism involved in transferring
the light-energy to the drivers; a means of warming the ship in
interstellar space; a main horizontal drive for forward and backward
motion as well as braking; three smaller vertical power units to give
them freedom of direction in climb or descent; other smaller horizontal
power units for turning and moving sideways.

The ships, they decided, must be capable of six or seven thousand miles
a second. They would need three types of ships: a small single-man
speedster, without bunk or living quarters, simply a little power plant
and weapon. Designed for speed and mobility, it would be very hard to
hit, and because of its own offensive power would be dangerous to the
enemy. They would need a fleet of mother ships--ships that would hold
both the speedsters and their pilots--say thirty to a cruiser. There
would also be some ten-man scouts, operating in the same manner as the
larger cruisers, but with a smaller fleet of speedsters dependent on
them.

"For defense," Arcot concluded, "we'll have to depend on armor as heavy
as we can make and still remain within the bounds of practical
construction. I don't believe we'll be able to build up enough mass to
insulate against their negative catalysis ray. We'll have to depend on
mobility and offense.

"But now let's get back to work. I think, Fuller, that you might call in
the engineers of all the big aircraft and machine tool manufacturers and
fabricators, and have them ready to start work at once when the plans
are finally drawn up. You'd better get in touch with the Venerian
producers, too. Those new works in Sorthol, Kaxor, will certainly be
able to help a lot.

"I suppose the Interplanetary Patrol men will have something to say, so
they better be called in. Likewise the Venerian Council. Morey, maybe
your dad can handle some of this."

As one they arose and set to work on their respective tasks--the
planning and building of the Earth-Venus war fleet.




V


Despite their utmost endeavor and the hard work of the industrial might
of two worlds, it was nearly six weeks before the fleet had grown to a
thing of importance. The tests to which they subjected the tiny
speedsters had been more than satisfactory. They behaved wonderfully,
shooting about at terrific speed, and with all the acceleration a pilot
could stand. These speedsters were literally piloted projectiles, and
their amazing mobility made them a powerful arm of offense.

There came into being a special corp dubbed, oddly enough, the "Rocket
Squad", a group of men who could stand plenty of "G's". This "Rocket
Squad" was composed solely of Terrestrians, for they were accustomed to
the gravity of Earth and could stand greater acceleration strains than
could the Venerians. The pick of the Air Patrol formed the nucleus of
this new military organization; and in short order, so great is the
appeal of the new and novel, the cream of the young men of the planet
were competing for a place among the Rocketeers.

Each ship, both speedster and mother craft, was equipped with an
invisibility locator, a sensitive short-wave directional receiver, that
would permit the operator to direct his rays at invisible targets. The
ships themselves could not be made invisible, since they depended in
their very principle on the absorption of light-energy. If the walls of
every part of the ship were perfectly transparent, they could absorb no
energy at all, and they would still be plainly visible--even more so
than before! They must remain visible, but they could also force the
enemy to remain visible.

Each ten-man ship carried an old-fashioned cannon that was equipped to
hurl cannisters carrying the luminous paint. They decided that these
would have advantages, even if the invaders did not use invisibility,
for in space a ship is visible only because it reflects or emits light.
For this reason the ships were not equipped with any portholes except in
the pilot room and at the observation posts. No light could escape. To
reduce the reflection to the absolute minimum, the ships had each been
painted with a 99% absorptive black. In space they would be exceedingly
difficult targets.

The heating effect of the sun on the black pigment when near the great
star was rather disagreeably intense, and to cool the speedsters they
had installed molecular director power units, which absorbed the heat
and used the energy to drive the ship. Heaters offset the radiation loss
of the black surface when too far from the sun.

Each of the speedsters was equipped with a small machine-gun shooting
luminous paint bullets. One of these, landing on another craft, made it
visible for at least two hours, and since they could cover an area of
about thirty feet, they were decidedly effective.

It was found that ray practice was rather complicated. The government
had ranges set up in great mountain districts away from any valuable
property, but they soon found that spatial warplay could not be carried
on on Earth. The rays very quickly demolished the targets, and in a
short time made good progress toward demolishing the mountains as well.
The problem was solved by using the barren surface of the moon and the
asteroid belt beyond Mars as a proving ground.

The ships were sent out in squadrons as fast as they could be finished
and the men could be brought together and trained. They were
establishing a great shield of ships across all that section of the
system whence the Nigrans had appeared, and they hoped to intercept the
next attack before it reached Earth, for they were certain the next
attack would be in full force.

Arcot had gone to the conference held on Venus with the other men who
had investigated the great wrecks, and each scientist had related his
view of things and had offered suggestions. Arcot's idea of the black
star was not very favorably received. As he later told Wade and Morey,
who had not gone, there was good reason for their objection to his idea.
Though the scientists were willing to admit that the invaders must have
come from a great distance, and they agreed that they lived in an
atmosphere of hydrogen, and judging from their pale skins, that they
were not used to the rays of a sun, they still insisted on the theory of
an outer planet of Sol.

"You remember," explained Arcot, "several years ago there was
considerable discussion about the existence of a planet still further
out from the sun than Pluto. It is well known that there are a number of
irregularities in the orbits of Neptune and Pluto that can't be caused
by known planets, and an outer planet could have the necessary mass and
orbit to account for them.

"This attack from outer space was immediately taken as proof of that
theory, and it was very easily supported, too. My one good point that
stood for any length of time under their attacks was the fact that those
ships weren't developed in a year, nor a century, and that the chemical
constitution of the men was so different. There were no new elements
discovered, except the light-matter, but they are rather wondering about
the great difference of earthly chemical constitution and the
constitution of these invaders.

"They had one argument that was just about enough to throw mine out,
though they pointed to the odds against the thing happening. You know,
of course, how planets are formed? They are the results of tidal action
on two passing suns.

"You can imagine two mighty stars careening through space and then
drawing slowly nearer, till at last they come within a few billion miles
of each other, and their gigantic masses reach out and bind them with a
mighty chain of gravity. Their titanic masses swing about each other,
each trying to pull free, and continue its path about the center of the
galactic system. But as their huge bulks come nearer, the chains that
bind them become stronger and stronger, and the tremendous pull of the
one gargantuan fire ball on the other raises titanic tides of flame.
Great streamers of gas shoot out, and all the space about is lighted by
the flaming suns. The pull of gravity becomes more and more intense, and
as the one circles the other, the tide is pulled up, and the mighty ball
of fire, which, for all its existence has been practically motionless as
far as rotation goes, begins to acquire a greater and greater rotational
speed as the tidal drag urges it on. The flames begin to reach higher
and higher, and the tides, now urged from the sun by centrifugal force,
rise into an ever greater crest, and as the swinging suns struggle to
break loose, the flaming gas is pulled up and up, and becomes a mighty
column of fire, a column that reaches out across three--four--a dozen
millions of miles of space and joins the two stars at last, as
stalactites and stalagmites grow together. A flaming tie of matter joins
them, two titanic suns, and a mighty rope of fire binds them, while far
mightier chains of gravity hold them together.

"But now their original velocity reasserts itself, and having spiraled
about each other for who can say how long--a year--a million years
seems more probable--but still only an instant in the life of a
star--they begin to draw apart, and the flaming column is stretched out,
and ever thinner it grows, and the two stars at last separate. But now
the gas will never fall back into the sun. Like some giant flaming cigar
it reaches out into space and it will stay thus, for it has been set in
rotation about the sun at such a speed as is needed to form an orbit.
The giant mass of gas is, however, too cool to continue to develop
energy from matter, for it was only the surface of the sun, and cool. As
it cools still further, there appear in it definite condensations, and
the beginnings of the planets are there. The great filament that
stretched from the sun to sun was cigar-shaped, and so the matter is
more plentiful toward the center, and larger planets develop. Thus
Jupiter and Saturn are far larger than any of the others. The two ends
are tapering, thus Earth is larger than Venus, which is larger than
Mercury, and Uranus and Neptune are both smaller than Saturn, Pluto
being smaller than either.

"Mars and the asteroids are hard to explain. Perhaps it is easier to
understand when we remember that the planets thus formed must
necessarily have been rotating in eccentric orbits when they were first
born, and these planets came too near the sun while gaseous, or nearly
so, and Mars lost much of its matter, while the other, which now exists
only as the asteroids, broke up.

"But now that other flaming star has retired, wandering on through
space. The star has left its traces, for behind it there are planets
where none existed before. But remember that it, too, must have planets
now.

"All this happened some 2,000 million years ago.

"But in order that it might happen, it requires that two stars pass
within the relatively short distance of a few billion miles of each
other. Space is not overcrowded with matter, you know. The density of
the stars has been compared with twenty tennis balls roaming about
8,000-mile sphere that the Earth fills up--twenty tennis balls in some
270 billion cubic miles of space. Now imagine two of those tennis
balls--with plenty of room to wander in--passing within a few yards of
each other. The chances are about as good as the chances of two stars
passing close enough to make planets.

"Now let us consider another possibility.

"The Black Star, as I told you, has planets. That means that it must
have thus passed close to another star. Now we have it coming close to
another sun that has been similarly afflicted. The chances of that
happening are inconceivably small. It is one chance in billions that the
planets will form. Two stars must pass close to each other, when they
have all space to wander about in. Then those afflicted stars separate,
and one of them passes close by a new star, which has thus been
similarly afflicted with that one chance in billions--well, that is then
a chance in billions of billions.

"So my theory was called impossible. I don't know but what it is.
Besides, I thought of an argument the other men didn't throw at me. I'm
surprised they didn't, too--the explanation of the strange chemical
constitution of these men of a solar system planet would not be so
impossible. It is quite possible that they live on a planet revolving
about the sun which is, nevertheless, a planet of another star. It is
quite conceivable to me that the chemical constitution of Neptune and
Pluto will be found to be quite different from that of the rest of our
planets. The two filaments drawn out from the suns may not have mingled,
though I think they did, but it is quite conceivable that, just before
parting, our sun tore one planet, or even two or three, from the other
star.

"And that would explain these strange beings.

"My other ideas were accepted. The agreed-on plan for the release of
energy, and the source of the power." Arcot puffed on his pipe
meditatively for several moments, then stood up and stretched.

"Ho--I wish they'd let me go on active duty with the space fleet! A
scientific reputation can be an awful handicap at times," he grinned. He
had been rejected very emphatically when he had tried to enlist. The
Interplanetary governments had stated flatly that he was too important
as a scientist to be risked as a pilot of a space ship.

On two worlds the great construction plants were humming with activity.
Civilian production of all but the barest essentials had been put aside
for the duration of the emergency. Space ships were being turned out at
top speed, getting their fuel from the wrecks of the invaders' cruisers.
Each ship needed only a small amount of the light-metal, for the energy
content was tremendous. And those ships had been gigantic.

Already there was a fleet of speedsters and mother ships out there in
space, and with every passing hour others left the home planets, always
adding to the fighting force that was to engage the attackers deep in
space, where no stray ships might filter through to destroy the cities
of Earth or Venus. Assembly lines were now turning out ships so rapidly
that the training of their operators was the most serious problem. This
difficulty had finally been overcome by a very abbreviated training
course in the actual manipulation of the controls on the home planets,
and subsequent training as the squadrons raced on their outward courses.

It was soon decided that there must be another service beside that of
the ordinary ships. One plant was devoted to making huge interstellar
liners. These giants, made on Venus, were nearly a quarter of a mile
long, and though diminutive in comparison with the giant Nigran ships,
they were still decidedly large. Twelve of these could be completed
within the next month, it was found; and one was immediately set aside
as an officers' headquarters ship. It was recognized that the officers
must be within a few hundred thousand miles of the actual engagements,
for decisions would have to be made without too much loss of time in the
transmission of reports.

The ship must not be brought too near the front lest the officers be
endangered and the entire engagement lost for want of the organizing
central headquarters. The final solution had been the huge central
control ship.

The other large vessels were to be used to carry food and supplies. They
were not to enter the engagement, for their huge size would make them as
vulnerable to the tiny darting mites of space as the Nigran ships had
been to the Interplanetary Patrol. The little ships could not
conveniently stock for more than a week of engagement, then drop back to
these warehouses of space, and go forward again for action.

Throughout the long wait the officers of the Solarian forces organized
their forces to the limit of their ability, planning each move of their
attack. Space had been marked off into a great three-dimensional map,
and each ship carried a small replica, the planets moving as they did in
their orbits. The space between the planets was divided off into
definite points in a series of Cartesian co-ordinates, the sun being the
origin, and the plane of the elliptic being the X-Y plane.

The OX line was taken pointing toward one of the brightest of the fixed
stars that was in the plane of the elliptic. The entire solar system was
thus marked off as had been the planets long ages before, into a system
of three dimensional latitude and longitude. This was imperative, in
order to assure the easy location of the point of first attack, and to
permit the entire fleet to come into position there. A scattered guard
was to remain free, to avoid any false attacks and a later attack from a
point millions of miles distant. Earth and Venus were each equipped with
gigantic ray projectors, mighty weapons that could destroy anything,
even a body as large as the Moon, at a distance of ten thousand miles.
Still, a ship might get through, and with the death ray--what fearful
toll might be exacted from a vast city such as Chicago--with its thirty
millions! Or Karos, on Venus, with its fifteen and one half millions!

The tension became greater and greater as with each passing day the
populace of two worlds awaited the call from the far-flung guard. The
main bulk of the fleet had been concentrated in the center of their
great spherical shell of ships. They could only wait--and watch--and
prepare! Hundreds of miles apart, yet near enough so that no ship
except perhaps a one-man craft could pass them undetected; and behind
them were ships with delicate apparatus that could detect any foreign
body of any size whatever within a hundred thousand miles of them.

The Solar System was prepared to repel boarders from the vast sea of
space!




VI


Taj Lamor gazed down at the tremendous field below him. In it lay close
packed a great mass of ships, a concourse of Titans of Space,
dreadnoughts that were soon to set out to win--not a nation, not even a
world, but to conquer a solar system, and to win for their owners a vast
new sun, a sun that would light them and heat them for long ages to
come.

Momentarily Taj Lamor's gaze followed the retreating figure of Tordos
Gar, the Elder; a figure with stooped shoulders and bowed head. His
quiet yet vibrant parting words still resounded in his ears:

"Taj Lamor, remember what I tell you. If you win this awful war--you
lose. As will our race. Only if you lose will you win."

With a frown Taj Lamor stared down at the vast metal hulls glistening
softly in the dull light of far-off stars, the single brightly beaming
star that was their goal, and the dim artificial lighting system. From
the distance came to him the tapping and humming of the working machines
below as they strove to put the finishing touches to the great ships.

He raised his eyes toward the far-off horizon, where a great yellow star
flamed brilliantly against the black velvet of space. He thought of that
planet where the sky had been blue--an atmosphere of such intensity that
it colored the sky!

Thoughtfully he gazed at the flaming yellow point.

He had much to consider now. They had met a new race, barbarians in
some ways, yet they had not forgotten the lessons they had learned; they
were not decadent. Between his eon-old people and their new home stood
these strange beings, a race so young that its age could readily be
counted in millennia, but withal a strong, intelligent form of life. And
to a race that had not known war for so many untold ages, it was an
unthinkable thing that they must kill other living, intelligent beings
in order that they might live.

They had no need of moving, Tordos Gar and many others had argued; they
could stay where they were forever, and never find any need for leaving
their planet. This was the voice of decadence, Taj Lamor told himself;
and he had grown to hate that voice.

There were other men, men who had gone to that other solar system, men
who had seen vast oceans of sparkling water, showering from their
ruffled surfaces the brilliant light of a great, hot sun. They had seen
towering masses of mountains that reached high into the blue sky of a
natural atmosphere, their mighty flanks clothed with green growth;
natural plants in abundance.

And best of all, they had fought and seen action, such as no member of
their race had known in untold ages. They knew Adventure and Excitement,
and they had learned things that no member of their ancient race had
known for millennia. They had learned the meaning of advancement and
change. They had a new ardor, a new strength, a new emotion to drive
them, and those who would have held them back became enthusiasts
themselves. Enthusiasm may be contagious, but the spirit of their
decadence was rapidly failing before this new urge. Here was their last
chance and they must take it; they would!

They had lost many men in that battle on the strange world, but their
race was intelligent; they learned quickly, the small ships had been
very hard targets, while their big ships were too easy to strike. They
must have small ships, yet they must have large ships for cargo, and for
the high speed driving apparatus. The small ships were not able to
accelerate to the terrific speed needed. Once their velocity had been
brought up to the desired value, it was easy to maintain it with the
infinitely small friction of space as the only retarding force; one atom
per cubic inch was all they must meet. This would not hold them up, but
the great amount of fuel and the power equipment needed to accelerate to
the desired speed could not be packed into the small ship. Into the vast
holds of the huge ships the smaller ones were packed, long shining rows
of little metal projectiles. Tiny they were, but they could dart and
twist and turn as swiftly as could the ships they had met on that other
world--tiny ships that flashed about with incredible suddenness, a
target that seemed impossible to hit. These ships would be a match for
those flashing motes of the Yellow Sun. Now it might be that their great
transport and battle ships could settle down to those worlds and arrange
them for their own people!

And they had discovered new weapons, too. One of their mightiest was a
very old apparatus, one that had been forgotten for countless ages. A
model of it was in existence in some forgotten museum on a deserted
planet, and with it long forgotten tomes that told of its principles,
and of its consequences. Invisibility was now at their command. It was
an ancient weapon, but might be exceedingly effective!

And one other. They had developed a new thing! They had not learned of
it in books, it was their invention! They did not doubt that there were
other machines like it in their museums, but the idea was original with
them. It was a beam of electrical oscillatory waves, projected with
tremendous energy, and it would be absorbed by any conductor. They could
melt a ship with this!

And thus that great field had been filled with Giants of Space! And in
each of these thousand great warships there nestled three thousand tiny
one-man ships.

Here was a sight to inspire any race!

Taj Lamor watched as the last of the working machines dragged its slow
way out of the great ships. They were finished! The men were already in
them, waiting to start, and now there was an enthusiasm and an activity
that had not been before; now the men were anxious to get that long
journey completed and to be there, in that other system!

Taj Lamor entered his little special car and shot swiftly down to the
giant cruisers. He stepped out of his little craft and walked over to
the tube conveyor ready for the trip to the nose of the great vessel.
Behind him attendants quickly moved his car to a locked cradle berth
beside long rows of similar vehicles.

A short while later those who were to remain on the dark planet saw the
first of the monsters of space rise slowly from the ground and leap
swiftly forward; then as methodically as though released by automatic
machinery, the others leaped in swift pursuit, rushing across half a
world to the tremendous space lock that would let them out into the
void. In a long, swift column they rushed on. Then one at a time they
passed out into the mighty sea of space. In space they quickly formed
and set out.

As though by magic, far to the left of their flight, there suddenly
appeared a similar flight of giant ships, and then to the right, and
above them, another seemed to leap out of nothingness as the ships of
other planets came into sight. Quickly they formed a vast cone about
their leader's ship, a protecting screen, yet a powerful offensive
formation.

Endlessly, it seemed, they sped on through the darkness. Then as the
yellow star flamed brighter and brighter before them, they slowed their
ships till the small fliers could safely be released into space.

Like a swarm of insects flying about giant birds of space the little
ships circled the mighty masses of the battle cruisers. So huge were
they, that in the combined mass of the fleet there rested sufficient
gravitational attraction to force the little fliers to form orbits about
them. And so they sped on through the void, the vast conical fleet with
its slowly circling belt of little ships. A fleet whose counterpart had
never entered the Solar System.

It was well beyond the orbit of Pluto that the first of the Solarian
scouts detected the approaching invasion fleet. The tension that had
gripped Earth and Venus and their guardian ships for so long a time
suddenly snapped; and like a great machine set into sudden motion, or a
huge boulder, balanced, given the last push that sends it spinning with
destructive violence down a slope, the fleet went into action.

It was merely a little scout, a ten-man cruiser, that sent in the
message of attack, and then, upon receiving headquarters' permission,
went into action. Some of the tacticians had wanted to try to get the
entire fleet into battle range for a surprise attack in power; but
others felt that this could not possibly succeed. Most important, they
decided, was the opportunity of learning if the invaders had any new
weapons.

The Nigrans had no warning, for a ten-man cruiser was invisible to them,
though the vast bulk of their own ships stood out plainly, lighted by a
blazing sun. No need here to make the sun stand still while the battle
was finished! There was no change out here in all time! The first
intimation of attack that the Nigrans had was the sudden splitting and
destruction of the leading ship. Then, before they could realize what
was happening, thirty-five other destructive molecular motion beams were
tearing through space to meet them! The little ten-man cruiser and its
flight of speedsters was in action! Twenty-one great ships crumpled and
burst noiselessly in the void, their gases belching out into space in a
great shining halo of light as the sun's light struck it.

Unable to see their tiny enemies, who now were striking as swiftly, as
desperately as possible, knowing that death was practically certain,
hoping only to destroy a more equal number of the giants, they played
their beams of death about them, taking care to miss their own ships as
much as possible.

Another ship silently crumpled, and suddenly one cruiser right in the
line of the flight was brought to a sudden halt as all its molecules
were reversed. The ships behind it, unable to stop so suddenly, piled
up on it in chaotic wreckage! A vast halo of shining gas spread out
fifty thousand miles about, blinding further the other ships, the
radiance about them making it impossible to see their tiny enemies.

Now other of the Solarian ships were coming swiftly to the attack.
Suddenly a combination of three of the ten-man cruisers stopped another
of the great ships instantaneously. There was another soundless crash,
and the giant mass of wreckage that heaped suddenly up glowed dully red
from the energy of impact.

But now the little ships of the invaders got into action. They had been
delayed by the desperate attempts of the dreadnaughts to wipe out their
enemies with the death rays, and they could not cover the great
distances without some delay.

When a battle spreads itself out through a ten-thousand mile cube of
space--through a thousand billion cubic miles of space--it is impossible
to cover it instantaneously with any machine.

Already nearly a hundred and fifty of the giant liners had gone into
making that colossal mass of junk in space. They must protect the
remaining cruisers! And it was that flight of small ships that did
protect them. Many of the Solarians went down to death under their rays.
The death rays were exceedingly effective, but the heat rays were not
able to get quite as long a range, and they were easily detected by the
invisibility locators, which meant certain destruction, for a molecular
motion ray would be there in moments, once they had been located.

The main fleet of the Solar System was already on its way, and every
moment drew closer to this running battle, for the great ships of the
Nigrans had, although they were entering the system cautiously, been
going at a very high speed, as interplanetary speeds are measured. The
entire battle had been a running encounter between the two forces. The
Solarian force, invisible because of its small size, was certainly
getting the better of the encounter thus far, but now that the odds were
changing, now that the small ships had come into the fray, engaging
them at close range, they were not having so easy time of it.

It would be many hours before the full strength of the Solarian fleet
could be brought to bear on the enemy. They were not able to retire and
await their arrival, for they _must_ delay the Nigran fleet. If even one
of those great ships should safely reach the two planets behind them--!

But within a half hour of the original signal, the Rocket Squad had
thrown itself into the battle with a fervor and abandon that has given
that famous division a name that will last forever.

The small fliers of the Nigrans were beginning to take an appalling toll
in the thinning ranks of the Solarians. The coming of the Rocket Squad
was welcome indeed! They were able to maneuver as swiftly as the enemy;
the speedsters were harder to spot than the Solarian ten-man and
thirty-man boats. The Solarian speedsters were even smaller than the
comparable Nigran craft, and some of these did a tremendous amount of
damage. The heat ray was quite ineffective against the ten-man ships,
even when working at full capacity, when produced by the small
generators of the Nigran one-man boats. The cruisers could absorb the
heat and turn it into power faster than the enemy could supply it. Beams
from the monster interstellar liners were another matter, of course.

But the one-man speedsters had a truly deadly plan of attack against the
liners. The plan was officially frowned upon because of the great risks
the pilots must take. They directed their boats at one of the monster
ships, all the power units on at full drive. As close to target as
possible the man jumped from his ship, clothed, of course, in an
altitude suit equipped with a radio transmitter and receiver.

Death rays could not stop the speedsters, and with their momentum, the
invaders could not make it less deadly with their heat beam, for,
molten, it was still effective. A projectile weighing twenty-two tons,
moving a hundred miles a second, can destroy anything man can lift off a
planet! Their very speed made it impossible to dodge them, and usually
they found their mark. As for the risk, if the Solarian forces were
victorious, the pilots could be picked up later, provided too long a
time had not elapsed!

In the midst of the battle, the Solarians began to wonder why the Nigran
fleet was decreasing so rapidly--certainly they had not caused all that
damage! Then suddenly they found the answer. One of their ships--then
another--and another fell victim to a pale red ray that showed up like a
ghostly pillar of luminosity coming from nowhere and going nowhere! The
answer? The invaders' ships were becoming invisible! The invisibility
detectors were being overloaded now, and the hunt was hard, while the
Nigrans were slipping past them and silently destroying Solarian ships!
The molecular motion rays were quite effective on an invisible
ship--once it had been found. They were destroying the Nigrans as
rapidly as they were being destroyed, but they were letting some of them
slip past! The luminous paint bombs and bullets were now called into
play. All enemy ships were shot at with these missiles, and invisibility
was forestalled.

At long last the dark bulk of the main fleet approached, a scarcely
visible cloud of tiny darting metal ships. The battle so far had been a
preliminary engagement. The huge ships of the Nigrans were forced to
stop their attack, and releasing the last of the fliers, to retire to a
distance, protected by a screen of small ships, for they were helpless
against the Solarian speedsters. Invisibility fell into disfavor, too,
now that there were plenty of Solarian ships, for the Nigrans were more
conspicuous when invisible than when visible. The radio detector could
pick them out at once.

The entire Nigran fleet was beginning to reveal the disorder and
uncertainty that arose from desperation, for they were cornered in the
most undesirable position possible. They were outside the Solarian
fleet, and their ships were lighted by the glare of the sun. The
defenders, on the other hand, were in such a position that the enemy
could see only the "night" side of them--the shadowed side--and, as
there was no air to diffuse the light, they were exceedingly hard to
find. In the bargain, the radium paint was making life for the Nigrans a
brief and flitting thing!

The invaders began to pay an awful toll in this their first real
engagement. They lacked the necessary power to cover the entire Solarian
fleet with their death rays, and their heat weapons were of little help.
The power of the small ships did not count for much--and the big liners
could not use their weapons effectively for their small fliers must be
between them and their adversary. Despite this, however, the Nigrans so
greatly outnumbered the Earth-Venus forces that it looked as though a
long and costly war lay ahead.

At last the Solarian generals tried a ruse, a ruse they hoped would work
on these beings; but they who never before had to plan a war in space,
were not sure that their opponents had not had experience in the art.
True, the Nigrans hadn't revealed any especially striking
generalship--had, in fact, committed some inexcusable blunders--but they
couldn't be sure. Though they didn't know it, the Solarians had the
advantage of thousands of years of planetary warfare to rely on. This
stood them in good stead now.

The Nigrans were rallying rapidly. To their surprise, the forces of the
Solarians were dwindling, and no matter how desperately this remnant
fought, they could not hold back the entire force of the Nigran fliers.
At last it appeared certain that the small ships could completely engage
the Solarian fleet!

Quickly the giant cruisers formed a great dense cone of attack, and at a
given signal, the fliers cleared a hole for them through the great
disc-shaped shield of the defenders. And with all their rays fanned out
in a 100% overlap ahead of them, the Nigran fleet plunged through the
disc of ships at close to four hundred miles per second. They broke
through--were on their way to the unprotected planets!

The Solarian ships closed the gap behind them, and eighteen of the giant
ships burst into wreckage as powerful beams found them, but for the most
part the remnant of the defending forces were far too busy with the
fliers to attack the large ships. Now, as the monster engines of
destruction raced on toward the planets still approximately two billion
miles away, they knew that, far behind them, their fliers were engaging
the Solarians. They had left their guard--but the guard was keeping the
enemy occupied while they were free to drive in!

Then from nowhere came the counterattack! Nearly five thousand
thirty-man ships of Earth and Venus, invisible in the darkness of space,
suddenly leaped into action as the dreadnoughts sped past. Their
destroying rays played over the nigh-helpless giants, and the huge ships
were crumbling into colossal derelicts. With the last of their guard
stripped from them, they fell easy prey to the attackers. Faster than
they could keep count they were losing their warships of space!

The ruse had worked perfectly! Nearly all of the ten-man and one-man
ships had been left behind them in the original disc, while all the
thirty-man light cruisers, and a few hundred each of the ten-man and
one-man crafts sped away to form a great ring twenty thousand miles
farther back. The Nigran fleet had flown blindly into the ambush.

There was only one thing left for them to do. They were defeated. They
must return to their far-off black star and leave the Solarians in
possession of their worlds. For all battle purposes their great force
was nearly wiped out, only the fliers remained in force; and these could
no longer be carried in the remnant of the great liners. Swiftly they
fell back, passing again through the disc, losing thirty more vessels,
then raced swiftly away from the fleet of their enemies.

The Solarians, however, were not content. Their ships were forming in a
giant hollow cylinder, and as the sphere of the Nigrans retreated, their
beams playing behind them, the cylinder moved forward until it
surrounded them, and they raced together toward the distant lightless
sun. The Solar end of the cylinder swiftly closed, blocked by a group of
huge ships which had taken no visible part in the battle. The Nigrans
had stopped using their rays; and the Solarians followed in armed
readiness, not molesting as long as they were not molested.

Many days this strange flight lasted, till at last the great yellow sun,
Sol, had faded in the distance to an unusually brilliant star. Then,
suddenly visible out of the darkness, a strange black world loomed
ahead, and the Nigran ships settled swiftly toward it. Through the
airlocks the great liners settled to their planet. No action was taken
so long as the Solarian ships were not menaced, but for eight long
months the darting ships hung above the four englobed worlds of Nigra.

Then at last the astronomers of Earth and Venus sent through the
billions of miles of ether their message of safety. The guard could
return home, for the sun they had been guarding would soon be too far
from Earth or Venus to make any attack logical. Despite this, for years
to come the fleet would guard the rim of the System, just to be sure;
but it appeared that the suns had passed, never again to meet.

A strange thing had happened during the passing of the stars. Pluto no
longer circled Sol; it had been captured by Nigra! The great fleet
returned to a changed Solar system. Sol was still at its center, but
there were now ten planets, including two new ones that the sun had
captured from Nigra in return for Pluto; and all the planets had shifted
a bit in their orbits.

What the ultimate effect on the planets will be, we cannot say as yet.
The change thus far is certainly not very great, though a somewhat
warmer climate exists now on Earth, and it is a bit cooler on Venus. The
long-range difference, however, will be exceedingly interesting.

The Solar System has just passed through an experience which is probably
unique in all the history of the mighty nebula of which our sun is an
infinitesimal part. The chances that one star, surrounded by a system of
planets, should pass within a hundred billion miles of another star,
similarly accompanied, was one in billions of billions. That both
systems should have been inhabited by intelligent races--

It is easy to understand why the scientists could not believe Arcot's
theory of attack from another sun until they had actually seen those
other worlds.

In that war between two solar systems we learned much and lost much.
Yet, in all probability we gained more than we lost, for those two
new-old planets will mean tremendous things to us. Already scientists
are at work in the vast museums and ancient laboratories that are on
them, and every day new things are being discovered. We lost many men,
but we saved our worlds, and we learned many invaluable secrets from the
invaders. In addition, we have but scratched the surface of a science
that is at least a thousand million years old!




EPILOGUE


Taj Lamor looked out across the void of space toward a fading point of
yellow light. Far in the distance it glowed, and every second moved it
many more miles farther from him. They had lost their struggle for life
and a new sun, he had thought when he turned back, defeated, from that
distant sun. But time had brought new hope.

They had lost many men in that struggle, and their dwindling resources
had been strained to the limit, but now there was hope, for a new spirit
had been born in their race. They had fought, and lost, but they had
gained a spirit of adventure that had been dormant for millions of
years.

Below him, in the great dim mass that was their city, he knew that many
laboratories were in the full swing of active work. Knowledge and its
application were being discovered and rediscovered. New uses were being
found for old things, and their daily life was changing. It was again a
race awake, rejuvenated by a change!

As the great sea of yellow fire that was that strange sun had faded
behind their fleeing ships, leaving their dead planets still circling a
dead sun, he had thought their last chance was gone forever. But hope
had reawakened, with the birth of new ideas, new ways of doing things.

Tordos Gar had been right! They had lost--but in the losing, they had
won!

Taj Lamor shifted his gaze to a blazing point of light, where a titanic
sea of flame was burning with a brilliance and power that, despite the
greater distance, made the remote yellow sun seem pale and dim. The
blue-white glow told of a monster star, a star far brighter than the one
they had just left. It had become the brightest star in their heavens.
On their ancient star charts it was listed as a red giant, named
Tongsil-239-e, which meant it was of the fifth magnitude and very
distant. But in the long ages that had passed since it was classified,
it had become a mighty sun--a star in its prime.

How were they to reach it? It was eight and one half light years away!

Their search for the force that would swing a world from its orbit had
at last been successful. The knowledge had come too late to aid them in
their fight for the yellow sun, but they might yet use it--they might
even tear their planets from their orbits, and drive them as free bodies
across the void. It would take ages to make the trip--but long ages had
already passed as their dark planet swung through the void. What
difference would it make if they were or were not accompanied by a dead
star?

True, the star that was now their goal was a double star; their planets
could not find orbits about it, but they might remedy that--they could
tear one star free and hurl it into space, making the remaining sun
suitable for their use.

But they _would_ escape this dead sun.




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End of Project Gutenberg's The Black Star Passes, by John W Campbell