The Black Star Passes

by Jr. John W. Campbell

  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 landsmoothly, but at high speed. On the roof of the building they slowedwith startling rapidity, held back by electromagnets under the topdressing of the roof landing, as Arcot learned later.

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

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

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

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

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

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

  "They look as if they'd all been eating blueberries!" laughed Wade. "Iwonder 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--butthose people evidently have their blood based on hemocyanin. In us, theoxygen is carried to the tissues, and the carbon dioxide carried away byan iron compound, hemoglobin, but in many animals of Earth, the samefunction is performed by a copper compound, hemocyanin, which is anintense blue. I am sure that that is the explanation for these strangepeople. By the way, did you notice their hands?"

  "Yes, I had. They strike me as having one too many fingers--lookthere--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, thatwould be handy in placing nuts and bolts, and such fine work, wouldn'tit?"

  Suddenly a lane opened in the crowd, and from the great black and goldbuilding there came a file of men in tight-fitting green uniforms; afile of seven-foot giants. Obviously they were soldiers of someparticular branch, for in the crowd there were a number of men dressedin 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 youmight start making inquiries; the other can send a message to Earth, andget out of harm's way till help can come. I imagine these people arefriendly now, however--else I wouldn't go."

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

  The coin was flipped with due ceremony--it would decide which of themwere to have the distinction of being the first Terrestrians to set footon Venus. Arcot and Morey won, and they quickly put on the loose-fittingventilated cooling suits that they might live comfortably in the hot airoutside--for the thermometer registered 150 deg.!

  The two men quickly walked over to the airlock, entered, closed itbehind 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 asinging in their ears, and they had to swallow several times to equalizethe pressure.

  The guards at once fell into a double row on either side of them, andthe young officer strode ahead. He himself had curbed his curiosityafter the single startled glance he had given these strange men. Onlytheir hands were visible, for the cooling suits covered them almostcompletely, but the strange pink color must indeed have been startlingto 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 crowdabout them, were not so disinterested. They were looking in eageramazement at these men who had just saved their city, these strangesmall 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 heldin check by a handful of the deep blue uniformed men.

  "Those fellows would never hold such a Terrestrial crowd back ifvisitors 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 directionof approach. We might be some strange race of Venerians as far as theyknow."

  They walked briskly up to the massive gold and black entrance, andpassed through the great doors that seemed made of solid copper, paintedwith some clear coating that kept the metal lustrous, the rich colorshining magnificently. They stood open wide now, as indeed they alwayswere. Even the giant Venerians were dwarfed by these mighty doors asthey passed through into an equally vast hall, a tremendous room thatmust have filled all the front half of the ground floor of the giganticbuilding, a hall of graceful columns that hid the great supportingmembers. The stone, they knew, must serve the Venerians as marble servesus, but it was a far more handsome stone. It was a rich green, like thegreen of thick, heavy grass in summer when the rain is plentiful. Thecolor was very pleasing to the eye, and restful too. There was achecker-board floor of this green stone, alternated with another, astone of intense blue. They were hard, and the colors made a verystriking pattern, pleasingly different from what they had beenaccustomed to, but common to Venus, as they later learned.

  At last the party had crossed the great hall, and stopped beside a largedoorway. The officer halted for a moment, and gestured toward two of hismen, who remained, while the others walked quickly away. The diminishedparty stepped through the doorway into a small room whose walls werelined with copper, and an instant later, as the officer pushed a smallbutton, there was a low hiss of escaping air, and a copper gratingsprang quickly up across the opening of the elevator. He touched anotherbutton, and there was the familiar sinking feeling as the car rose, alow 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!" Moreyexclaimed. "The engineers of Terrestrial buildings have been wonderingfor 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 haverisen a long way!"

  "I should say so--I wonder how they do it. We've been rising for aminute and a half at a very fair clip--there we are; end of the line--Iwant to look at this car!" Arcot stepped over to the control board,looked at it closely, then stepped out and peered down between the carand the shaft as the copper grating fell, simultaneously pulling downwith 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 railsalongside, and the car just winds itself up! They have a motorunderneath, I'll bet, and just run it up in that way. They have neverdone that on Earth
because of the cost of running the car up without toomuch power. I think I see the solution--the car has electro-dynamicalbrakes, and descending, just slows itself down by pumping power into theline to haul some other car up. This is a mighty clever scheme!"

  As Arcot straightened, the officer beckoned to him to follow, andstarted down the long corridor which was lined on either side with largedoorways, much like a very exotic earthly office building. Passingthrough a long series of branching corridors they at last reached onethat terminated in a large office, into which the young officer ledthem. Snapping to attention, he spoke briefly and rapidly, saluted andretired with his two men.

  The man before whom the Terrestrians stood was a tall, kindly-faced oldgentleman. His straight black hair was tinged with bluish gray, and thekindly face bore the lines of age, but the smiling eyes, and the air ofsincere interest gave his countenance an amazingly youthful air. It waswarm and friendly despite its disconcerting blueness. He lookedcuriously, questioningly at the two men before him, looked at theirhands, 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 anexclamation on the part of each, they mutually released each other,Arcot feeling an uncomfortable sensation of heat, just as the Venerianfelt a flash of intense cold! Each stared from his hand to the hand ofthe other in surprise, then a smile curved the blue lips of the Venerianas 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 deg. Fahrenheit. It wouldnaturally be above room temperature, which is 150 deg. here, so that theyare most unpleasantly hot to us. Marvelous how nature adapts herself toher 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, smoothand solid. He drew quickly upon it with what appeared to be a pencil ofcopper. In a moment he handed the tablet to Arcot, who reached out forit, then changed his mind, and motioned that he didn't want to burn hisfingers. The old Venerian held it where Arcot could see it.

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

  The Venerian pointed to Mars and looked inquisitively at them. Arcotshook his head and pointed quickly to Earth. The Venetian seemed a bitsurprised at this, then thought a moment and nodded in satisfaction. Helooked at Arcot intently. Then to the latter's amazement, there seemedto form in his mind a thought--at first vague, then quickly takingdefinite form.

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

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

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

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

  "Mental telepathy," Arcot answered briefly. "I'm terribly thick from hispoint 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 thestrain, I'll find out sooner or later--so wait and see." He turned againto the Venerian.

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

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

  "Come along, Morey--we're going somewhere. He says this thoughttransference 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 kindlyseven-foot Venerian. After walking through a long series of halls, theyreached a large auditorium, where already there had gathered in thesemi-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 youthe ideas--you must learn the pronunciation, but this will be very muchquicker. Seat yourselves in these chairs and relax."

  The chairs had been designed for the seven-footers. These men were sixfeet and six feet six, respectively, yet it seemed to them, as they sankinto 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 yawnedprodigiously. There was no conscious awareness of his sinking into adeep slumber. It seemed that suddenly visions began to fill hismind--visions that developed with a returning consciousness--up from thedark, into a dream world. He saw a mighty fleet whose individual planeswere a mile long, with three-quarters of a mile wingspread--titanicmonoplanes, whose droning thunder seemed to roar through all space. Thensuddenly they were above him, and from each there spurted a great streamof dazzling brilliance, an intense glow that reached down, and touchedthe city. An awful concussion blasted his ears. All the world about himerupted in unimaginable brilliance; then darkness fell.

  Another vision filled his mind--a vision of the same fleet hanging overa giant crater of molten rock, a crater that gaped angrily in a plainbeside low green hills--a crater that had been a city. The giants of theair circled, turned, and sped over the horizon. Again he was withthem--and again he saw a great city fuse in a blazing flash of blindinglight--again and yet again--until around all that world he saw smokingruins of great cities, now blasted crimson craters in a world of fearfuldesolation.

  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 reachin at them, and the roaring of the mighty propellers was a thinwhine--then suddenly that was gone, and from the tail of each of thetitanic machines there burst a great stream of light, a blazing columnthat roared back, and lit all space for miles around--rocket jets thatsent 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 greatplanes began falling now--falling at an awful speed into the upper airof the planet, and in an instant the rocket flares were gone, fading anddying in the dense air. Again there came the roar of the mightypropellers. Then swiftly the fleet of giants swooped down, lower andlower. He became aware of its destination--a spot he knew must be NewYork--but a strangely distorted New York--a Venerian city, where NewYork should have been. And again, the bombs rained down. In an instantthe gigantic city was a smoking ruin.

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

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

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

  "We have taught you our language as quickly as possible--you may have aheadache, but you must know what we know as soon as possible. It maywell be that the fate of two worlds hangs on your actions. These menhave concentrated on you and taught you very rapidly with the massedpower of their minds, giving you visions of what we know to be inpreparation. You must get back to your wonderful ship as quickly aspossible; and yet you must know what has happened here on our world inthe 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 alsolearned, you may tell him."

  Quickly Arcot followed the Venerian down the long corridors of thebuilding. 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 methis escort; and there he listened to a new history--the history ofanother planet.

  "My name is Tonlos," the old man said. "I am a leader of mypeople--though my title and position are unimportant. To explain wouldentail a prolonged discussion of our social structure, and there is notime for that. Later, perhaps--but now to our history.

  "Twenty centuries ago," Tonlos continued, "there were two great rivalnations on this planet. The planet Turo is naturally divided so thatthere would be a tendency toward such division. There are two enormousbelts of land around the globe, one running from about 20 degrees northof the equator to about 80 degrees north. This is my country, Lanor. Tothe south there is a similar great belt of land, of almost identicalsize, Kaxor. These two nations have existed for many thousands of ouryears.

  "Two thousand years ago a great crisis arose in the affairs of theworld--a great war was in process of starting--but a Lanorian developeda weapon that made it impossible for the Kaxorians to win--and war wasaverted. The feeling was so strong, however, that laws were passed whichstopped all intercourse between the two nations for these thousands ofyears. By devious ways we've learned that Kaxor has concentrated on thestudy of physics, perhaps in hopes of finding a weapon with which theycould threaten us once more. Lanor has studied the secrets of the humanmind 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 greatextent. Recently, however, we have again taken up this science, since italone of the main sciences had not received our study. Only twenty-fiveyears have been spent on these researches, and in that short time wecannot hope to do what the Kaxorians have done in two thousand.

  "The secret of the heat ray, the weapon that prevented the last war, hadbeen almost forgotten. It required diligent research to bring it to lifeagain, 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 smeltour ores. It was this alone that allowed this city to put up the slightresistance that we did. We were surely doomed. This is the capital ofLanor, Sonor. We--and the nation--would have fallen but for you.

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

  "Yes--we can signal easily," Arcot answered; he struggled with the newlyacquired language. "I do not know the word in your tongue--it may bethat you do not have it--radio we call it--it is akin to light, but ofvastly longer wavelength. Produced electrically, it can be directed likelight and sent in a beam by means of a reflection. It can penetrate allsubstances except metals, and can leak around them, if it be notdirectional. With it I can talk readily with the men of Earth, and thisvery night I will."

  Arcot paused, frowning thoughtfully, then continued, "I know there'sdefinite need for haste, but we can't do anything until Morey hasreceived the knowledge you've given me. While we're waiting here, Imight 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 ofthe physical makeup of Venus. He learned that iron was an exceedinglyrare element on the planet, while platinum was relatively plentiful.Gold, though readily available, was considered a nuisance, since it wasof no practical value due to its softness, excessive weight and itsaffinity for many catalysts. Most of the other metallic elements werepresent in quantities approximating those of Earth, except for anelement called "morlus". When Tonlos mentioned this, Arcot said:

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

  "Why--here is some!"

  Tonlos handed Arcot a small block of metal that had been used as aweight 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 hadseen that afternoon. Arcot examined it carefully, handicapped somewhatby its heat. He picked up a small copper rod and tried to scratch it butthere was no noticeable effect.

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

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

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

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

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

  "Your world is vastly different from ours," Arcot commented. He toldTonlos of the different metals of Earth, the non-metals, and theiroccurrence. But try as he would, he could not place the metal Tonlos hadgiven him.

  Morey's arrival interrupted their discussion. He looked very tired, andvery serious. His head ached from his unwonted mental strain, just asArcot's had. Briefly Arcot told him what he had learned, concluding witha question as to why Morey thought the two planets, both members of thesame 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 thesun, charting the locatio
n of the different elements. We've seenhydrogen, oxygen, silicon and others, and as the sun aged, the elementsmust have been mixed up more and more thoroughly. Yet we have seen thevast areas of single elements. Some of those areas are so vast that theycould easily be the source of an entire world! I wonder if it is notpossible that Earth was thrown off from some deposit rich in iron,aluminum and calcium, and poor in gold, radium and those othermetals--and particularly poor in one element. We have located in the sunthe spectrum of an element we have named coronium--and I think you havea specimen of coronium in your hand there! I'd say Venus came from acoronium-rich region!"

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

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

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

  "I know we were gone a long time--but when you hear the reason you'llagree 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, tellthem to call in Dad and your father, and to have a couple of taperecorders on the job. We'll want a record of what I have to send. Saythat we'll call back in an hour." Then, while Morey was busy down in thepower room sending the signals out across the forty million miles ofspace that separated them from their home planet, Arcot told Wade andFuller what they had learned.

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

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

  At the supper table Wade and Arcot reported to the others the curiousconstants they had discovered for coronium. It was not attacked by anyacid except boiling selenic acid, since it formed a tremendous number ofinsoluble salts. Even the nitrate violated the long-held rule that "allnitrates are soluble"--it wouldn't dissolve. Yet it was chemically moreactive than gold.

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

  Fuller whistled in awe. "No wonder they can make a plane like that whenthey have such a metal to work with." The designing engineer had visionsof 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, andthe men went to the power room. The television screen was struggling toform 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 hadreached him already, sketchy though it was. After brief though warmgreetings, his son rapidly outlined to him the full extent of theirdiscoveries, and the force that Earth would have to meet.

  "Dad, these Kaxorians have planes capable of far more than a thousandmiles an hour in the air. For some reason the apparatus they use topropel them in space is inoperative in air, but their propellers willdrive them forward faster than any plane Earth ever saw. You must startat once on a fleet of these molecular motion planes--and a lot of thegas Wade developed--you know how to make it--the animation suspendinggas. They don't have it--and I believe it will be useful. I'll try todevelop some new weapons here. If either of us makes any progress alongnew lines--we'll report to the other. I must stop now--a Lanoriandelegation is coming." After a few words of farewell, Arcot severedconnections with the Earth and arose to await the arrival of thevisitors.

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

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

  "Think a moment--they are going to visit a place whose temperature isseventy degrees colder than their room temperature. In the bargain,Venus never has any seasonal change of temperature, and a heavy bank ofclouds that eternally cover the planet keeps the temperature as constantas a thermocouple arrangement could. The slight change from day to nightis only appreciable by the nightly rains--see--the crowd is beginning tobreak 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 willsupply enough heat, in condensing, to prevent a temperature drop of morethan two or three degrees. These men are not used to changes intemperature as we are and hence they must protect themselves far morefully."

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

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

  But there was one thing he could show them, and he did. There were nosamples of the liquids he wanted, but their chemistry was developed to apoint that permitted the communication of the necessary data and Arcottold them the formula of Wade's gas. Its ability to penetrate anymaterial at ordinary temperatures, combined with its anestheticproperties, gave it obvious advantages as a weapon for rendering theopposing forces defenseless.

  Since it was able to penetrate all substances, there was no means ofstoring it. Hence it was made in the form of two liquids which reactedspontaneously and produced the gas, which was then projected to the spotwhere needed.

  Arcot asked now that the Venerian chemists make him a supply of thesetwo liquids; and they promptly agreed. He felt he would have a fightingchance in combatting the enemy if he could but capture one of theirflying forts. It seemed a strange task! Capturing so huge a machine withonly the tiny _Solarite_--but Arcot felt there was a good possibility ofhis doing it if he but had a supply of that gas.

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

  It was quite late when the Venerians left, to go again into the scaldinghot rain, rain that seemed to them to be a cold drizzle. After they hadgone, the Terrestrians turned in for the night, leaving a telephoneconnection with the armed guard outside.

  * * * * *

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

  "We need some pure water--water free of copper salts. I think it wouldbe 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--theship's tanks need recharging. I'd like about a ton of the drinkingwater." Arcot had to translate the Terrestrian measures into thecorresponding Venerian terms, of course, but still the officer seemedpuzzled. Such a large amount of water would create a real problem intransportation. After apparently conferring by telepathic means with hissuperiors, the officer asked if the _Solarite_ could be moved to somemore accessible place.

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

  The _Solarite_ was moved to the bank of the little river and theelectrolysis apparatus was set up beside it. During the previous day,and ever since they had landed on Venus, all their power had been comingfrom the storage cells, but now that the electrolysis apparatus was toestablish 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 intothe huge tanks. The apparatus they were using produced the gas veryrapidly, but it was near nightfall before the huge tanks had again beenfilled. Even then there was a bit more room for the atomic hydrogen thatwas simultaneously formed, although twice as much hydrogen as oxygen wasproduced. Its task completed, the _Solarite_ rose again and sped towardthe distant city.

  A soft red glow filled the sky now, for even through the miles of cloudsthe intense sun was able to force some direct rays, and all the city waslighted with that warm radiance. The floodlights had not yet been turnedon, but the great buildings looming high in the ruddy light werewonderfully impressive, the effect being heightened by the plannedconstruction, for there were no individual spires, only a single massthat grew from the ground to tower high in the air, like some man-mademountain.

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

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

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

  "It, too, is much like iodine, but heavier. It is a black solid meltingat 570 degrees; it is a metallic looking element, will conductelectricity somewhat, oxidizes in air to form an acidic oxide, and formsstrong oxygen acids. It is far less active than iodine, except towardoxygen. It is very slightly soluble in water. It does not react readilywith 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 theelement that precedes niton. Is it heavier than that?"

  "No," replied Tonlos; "it is just lighter than that element you callniton. 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 sawthe quantity that they had said was "rather disappointingly small" helaughed heartily.

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

  Again that night they spoke with Earth, and Morey, Senior, told themthat work was already under way on a hundred small ships. They wereusing all their own ships already, while the Government got ready to acton the idea of danger. It had been difficult to convince them thatsomeone on Venus was getting ready to send a force to Earth to destroythem; but the weight of their scientific reputation had turned thetrick. 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, andcapable of carrying large tanks of the gas-producing chemicals.

  It was near midnight, Venerian time, when they turned in. The followingday they planned to start for the Kaxorian construction camp. They hadlearned from Tonlos that there were but five of the giant planescompleted now, but there were fifteen more under construction, to makeup the fleet of twenty that was to attack Earth. These fifteen otherswould 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 learnits secrets, and then, if possible, with the weapons and knowledge oftwo worlds, defeat them. A large order!

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

  Far to the east and south of them the line of scout planes thatpatrolled all the borders of Lanor had been broken. Instantaneously, itseemed, out of the dark, its lights obscured, the mighty Kaxorian crafthad come, striking a tiny scout plane head on, destroying it utterlybefore 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 amagnesium flare, a blindingly brilliant light that floated down on aparachute, and in the blaze of the white light it gave off, the otherscouts at a few miles distance had seen the mighty bulk of the Kaxorianplane. At once they had dropped to the ground and then, by telephonelines, had sent their report to far off Sonor.

  In moments the interior of the _Solarite_ became a scene of swiftpurposeful activity. All day the Terrestrians had been able to do solittle in preparation for the conflict they knew must come, the battlefor two worlds. They had wanted action, but they had no weapons excepttheir 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.