At that moment Joe really thought of Sally for the first time in a good two hours. She'd been anxious that living in the Platform should be as normal and Earth-like as possible. The total absence of weight would be bad enough. She believed it needed to be countered, as a psychological factor in staying sane, by the effect of normal-seeming chairs and normal-tasting food, and not too exotic systems for eating.

Joe asked Brent about it.

"Oh, yes," said Brent mildly. "It's likely we'd all have gone off the deep end if there weren't some familiar things about. To have to drink from a cup that one squeezes is tolerable. But we'd have felt hysterical at times if we had to drink everything from the equivalent of baby bottles."

"Sally Holt," said Joe, "is a friend of mine. She helped design this stuff."

"That girl has every ounce of brains that any woman can be trusted with!" Brent said warmly. "She thought of things that would never have occurred to me! As a psychologist, I could see how good her ideas were when she brought them up, but as a male I'd never have dreamed of them." Then he grinned. "She fell down on just one point. So did everybody else. Nobody happened to think of a garbage-disposal system for the Platform."

It came into Joe's mind that garbage-disposal was hardly a subject one would expect to be discussing in interplanetary space. But the Platform wasn't the same thing as a spaceship. A ship could jettison refuse and leave it behind, or store it during a voyage and dump it at either end. But the Space Platform would never land. It could roll on forever. And if it heaved out its refuse from airlocks—why—the stuff would still have the Platform's orbital speed and would follow it tirelessly around the Earth until the end of time.

"We dry and store it now," said Brent. "If we were going to live, we'd figure out some way to turn it to fertilizer for the hydroponic gardens. It's hardly worth while as things are. Even then, though, the problem of tin cans could be hopeless."

The Chief wiped his mouth deliberately. He had helped load four guided-missile launching tubes, and he had been brought up to date on the state of things in the Platform. He growled in a preliminary fashion and said, "Joe."

Joe looked at him.

"We brought up six two-ton guided missiles," said the Chief dourly. "We'll have warning of other bombs coming up. We can send these missiles out to intercept 'em. Six of 'em. They can get close enough to set off their proximity fuses, anyhow. But what are we going to do, Joe, if somebody flings seven bombs at us? We can manage six—maybe. But what'll we do with the one that's left over?"

"Have you any ideas?" asked Joe.

The Chief shook his head. Brent said mildly. "We've worked on that here in the Platform, I assure you. And as Sanford puts it quite soundly, about the only thing we can really do is throw our empty tin cans at them."

Joe nodded. Then he tensed. Brent had meant it as a rather mirthless joke. But Joe was astonished at what his own brain made of it. He thought it over. Then he said, "Why not? It ought to be a very good trick."

Brent stared at him incredulously. Haney looked solemnly at him. The Chief regarded Joe thoughtfully out of the corner of his eye. Then Mike shouted gleefully. The Chief blinked, and a moment later grunted wrathful unintelligible syllables of Mohawk, and then tried to pound Joe on the back and because of his want of weight went head over heels into the air between the six walls of the kitchen.

Haney said disgustedly, "Joe, there are times when a guy wants to murder you! Why didn't I think of that?"

But Brent was looking at the four of them with a lively, helpless curiosity. "Will you guys let me in on this?"

They told him. Joe began to explain it carefully, but the Chief broke in with a barked and impatient description, and then Mike interrupted to snap a correction. But by that time Brent's expression had changed with astonishing suddenness.

"I see! I see!" he said excitedly. "All right! Have you got space suits in your ship? We have them. So we'll go out and pelt the stars with garbage. I think we'd better get at it right now, too. In under two hours we'll be a fine target for more bombs, and it would be good to start ahead of time."

Mike made a gesture and went floating out of the kitchen, air-swimming to go get space suits from the ship. The grin on his small face threatened to cut his throat. Joe asked, "Sanford's in command. How'll he like this idea?"

Brent hesitated. "I'm afraid," he said regretfully, "he won't like it. If you solve a problem he gave up, it will tear his present adjustment to bits. He's gone psychotic. I think, though, that he'll allow it to be tried while he swears at us for fools. He's most likely to react that way if you suggest it."

"Then," agreed Joe, "I suggest it. Chief——"

The Chief raised a large brown hand.

"I got the program, Joe," he said. "We'll all get set."

And Joe went floating unhappily through passage-tubes to the control room. He heard Sanford's voice, sardonic and mocking, as he reached the communications room door.

"What do you expect?" Sanford was saying derisively. "We're clay pigeons. We're a perfect target. We've just so much ammunition now. You say you may send us more in three weeks instead of a month. I admire your persistence, but it's really no use! This is all a very stupid business...."

He felt Joe's presence. He turned, and then sharply struck the communicator switch with the heel of his hand. The image on the television screen died. The voice cut off. He said blandly: "Well?"

"I want," said Joe, "to take a garbage-disposal party out on the outside of the Platform. I came to ask for authority."

Sanford looked at him in mocking surprise.

"To be sure it seems as intelligent as anything else the human race has ever done," he observed. "But why does it appeal to you as something you want to do?"

"I think," Joe told him, "that we can make a defense against bombs from Earth with our empty tin cans."

Sanford raised his eyebrows.

"If you happen to have a four-leaf clover with you," he said in fine irony, "I'm told they're good, too."

His eyes were bright and scornful. His manner was feverishly derisive. Joe would have done well to let it go at that. But he was nettled.

"We set off the last bombs," he said doggedly, "by shooting our landing rockets at them. They didn't collide with the bombs. They simply touched off the bombs' proximity fuses. If we surround the Platform with a cluster of tin cans and such things, they may do as well. Things we throw away won't drop to Earth. Ultimately, they'll actually circle us, like satellites themselves. But if we can get enough of them between us and Earth, any bombs that come up will have their proximity fuses detonated by the floating trash we throw out."

Sanford laughed.

"We might ask for aluminum-foil ribbon to come up in the next supply ship," said Joe. "We could have masses of that, or maybe metallic dust floating around us."

"I much prefer used tin cans," said Sanford humorously. "I'll take the watch here and let everybody go out with you. By all means we must defend ourselves. Forward with the garbage! Go ahead!"

His eyes were almost hysterically scornful as he waited for Joe to leave. Joe did not like it at all, but there was nothing to do but get out.

He found the Chief with a net bag filled with emptied tin cans. Haney had another. There were two more, carried by members of the Platform's four-man crew. They were donning their space suits when Joe came upon them. Mike was grotesque in the cut-down outfit built for him. Actually, the only difference was in the size of the fabric suit and the length of the arms and legs. He could carry a talkie outfit with its batteries, and the oxygen tank for breathing as well as anybody, since out here weight did not count at all. There were plastic ropes, resistant to extremes of temperature.

Joe got into his own space suit. It was no such self-contained space craft in itself as the fantastic story tellers dreamed of. It was not much more than an altitude suit, aluminized to withstand the blazing heat of sunshine in emptiness, and with extravagantly insulated soles to the magnetic boots. In theory, there simply is no temperature in space. In practice, a metal hull heats up in sunshine to very much more than any record-hot-day temperature on Earth. In shadow, too, a metal hull will drop very close to minus 250 degrees Centigrade, which is something like 400 degrees Fahrenheit below zero. But mainly the space boots were insulated against the almost dull-red-heat temperatures of long-continued sunshine.

A crewman named Corey moved into an airlock with one of the bags of empty tin cans. Brent watched in a routine fashion through a glass in the lock-door. The pumps began to exhaust the air from the airlock. Corey's space suit inflated visibly. Presently the pump stopped. Corey opened the outer door. He went out, paying plastic rope behind him. An instant later he reappeared and removed the rope. He'd made his line fast outside. He closed the outer lock-door. Air surged into the lock and Haney crowded in. Again the pumping. Then Haney went out, and was anchored to the Platform not only by his magnetic boots but by a rope fastened to a hand-hold. Brent went out. Mike. Joe came next.

They stood on the hull of the Space Platform, waiting in the incredible harsh sunshine of emptiness. The bright steel plates of the hull swelled and curved away on every hand. There were myriads of stars and the vast round bulk of Earth seemed farther away to a man in a space suit than to a man looking out a port. Where shadows cut across the Platform's irregular surface, there was utter blackness. Also there was horrible frigidity. Elsewhere it was blindingly bright. The men were specks of humanity standing on a shining metal hull, and all about them there was the desolation of nothingness.

But Joe felt strangely proud. The seventh man came out of the lock-door. They tied their plastic ropes together and spread out in a long line which went almost around the Platform. The man next to the lock was anchored to a steel hand-hold. The third man of the line also anchored himself. The fifth. The seventh. They were a straggling line of figures with impossibly elongated shadows, held together by ropes. They were peculiarly like a party of weirdly costumed mountaineers on a glacier of gleaming silver.

But no mountain climbers ever had a background of ten thousand million stars, peering up from below them as well as from overhead. Nor did any ever have a mottled greenish planet rolling by 4,000 miles beneath them, nor a blazing sun glaring down at them from a sky such as this.

In particular, perhaps, no other explorers ever set out upon an expedition whose purpose was to throw tin cans and dried refuse at all the shining cosmos.

They set to work. The space suits were inevitably clumsy. It was not easy to throw hard with only magnetism to hold one to his feet. It was actually more practical to throw straight up with an underhand gesture. But even that would send the tin cans an enormous distance, in time. There was no air to slow them.

The tin cans twinkled as they left the Platform's steel expanse. They moved away at a speed of possibly 20 to 30 miles an hour. They floated off in all possible directions. They would never reach Earth, of course. They shared the Platform's orbital speed, and they would circle the Earth with it forever. But when they were thrown away, their orbits were displaced a little. Each can thrown downward just now, for example, would always be between the Platform and the Earth on this side of its orbit. But on the other side of Earth it would be above the Platform. The Platform, in fact, became the center of a swarm, a cluster, a cloud of infinitesimal objects which would always accompany it and always be in motion with regard to it. Together, they should make up a screen no proximity fuse bomb could pierce without exploding.

Joe heard clankings, transmitted to his body through his feet.

"What's that?" he demanded sharply. "It sounds like the airlock!"

Voices mingled in his ears. The other walkie-talkies allowed everybody to speak at once. Most of them did. Then Joe heard someone laugh. It was Sanford's voice.

Sandford's aluminized, space-suited figure came clanking around the curve of the small metal world. The antenna of his walkie-talkie glittered above his head. He seemed to swagger against the background of many-colored stars.

Brent spoke quickly, before anyone else could question Sanford. His tone was mild and matter of fact, but Joe somehow knew the tension behind it.

"Hello, Sanford. You came out? Was it wise? Shouldn't there be someone inside the Platform?"

Sanford laughed again. "It was very wise. We're going to be killed, as you fellows know perfectly well. It's futile to try to avoid it. So very sensibly I've decided to spare myself the nuisance of waiting to be killed. I came out."

There was silence in the ear-phones of Joe's space suit radio. He heard his own heart beating loudly and steadily in the absolute stillness.

"Incidentally," said Sanford with almost hysterical amusement, "I fixed it so that none of us can get back in. It would be useless, anyhow. Everything's futility. So I've put an end to our troubles for good. I've locked us all out."

He laughed yet again. And Joe knew that in Sanford's madness it was perfectly possible for him to have done exactly what he said.

There were eight human beings on the Platform. All were now outside it, on its outer skin. They wore space suits with from half an hour to an hour's oxygen supply. They had no tools with which to break back into the satellite. And no help could possibly reach them in less than three weeks.

If they couldn't get back inside the Platform, Sanford, laughing proudly, had killed them all.



4

There was a babbling of angry, strained, tense voices in Joe's headphones. Then the Chief roared for silence. It fell, save for Sanford's quiet, hysterical chuckling. Joe found himself rather absurdly thinking that Sanford was not actually insane, except as any man may be who believes only in his own cleverness. Sooner or later it is bound to fail him. On Earth, Sanford's pride in his own intellect had been useful. He had been brilliant because he accepted every problem and every difficulty as a challenge. But with the Platform's situation seemingly hopeless, he'd been starkly unable to face the fact that he wasn't clever or brilliant or intelligent enough. If Joe's solution to the proximity fuse bombs had been offered before his emotional collapse, he could have accepted it grandly, and in so doing have made it his own. But it was too late for that now. He'd given up and worked up a frantic scorn for the universe he could not cope with. For Joe's trick to work would have made him inferior even to Joe in his own view. And he couldn't have that! Even to die, with the prospect that others would survive him, was an intolerable prospect. He had to be smarter than anybody else.

So he chuckled. The Chief roared wrathfully into his transmitter: "Quiet! This crazy fool's tried to commit suicide for all of us! How about it? Why can't we get back in? How many locks——"

Joe found himself thinking hard. He could be angry later. Now there wasn't time. Thirty or forty minutes of breathing. No tools. A steel hull. The airlocks were naturally arranged for the greatest possible safety under normal conditions. In every airlock it had naturally been arranged so that the door to space and the door to the interior could not be open at the same time. That was to save lives. To save air, it would naturally be arranged that the door to space couldn't be opened until the lock was pumped empty.

That in itself could be an answer. Joe said sharply, "Hold it, Chief! Somebody watch Sanford! All we've got to do is find which lock he came out of. He couldn't get out until he pumped it empty—and that unlocks the outer door!"

But Sanford laughed once more. He sounded like someone in the highest of high good humor.

"Heroic again, eh? But I took a compressed air bottle in the lock with me. When the outer door was open, I opened the stopcock and shut the door. The air bottle filled the lock behind me. Naturally I'd fasten the door after I came out! One must be intelligent!"

Joe heard Brent muttering, "Yes, he'd do that!"

"Somebody check it!" snapped Joe. "Make sure! It might amuse him to watch us die while he knew we could get back in if we were as smart as he is."

There were clankings on the hull. Men moved, unfastening the lines which held them to the hull to get freedom of movement, but not breaking the links which bound them to each other. Joe saw Haney go grimly back to the task of throwing away the stuff that they had brought out for the purpose. Then Mike's voice, brittle and cagey: "Haney! Quit it!"

Sanford's voice again, horribly amused. "By all means! Don't throw away our garbage! We may need it!"

A voice snapped, "This lock's fastened." Another voice: "And this...." Other voices, with increasing desperation, verified that every airlock was implacably sealed fast by the presence of air pressure inside the lock itself.

Time was passing. Joe had never noticed, before, the minute noises of the air pressure apparatus strapped to his back. His exhaled breath went to a tiny pump that forced it through a hygroscopic filter which at once extracted excess moisture and removed carbon dioxide. The same pump carefully measured a volume of oxygen equal to the removed CO_2 and added it to the air it released. The pump made very small sounds indeed, and the valves were almost noiseless, but Joe could hear their clickings.

Something burned him. He had been standing perfectly still while trying to concentrate on a way out. Sunshine had shone uninterruptedly on one side of his space suit for as long as five minutes. Despite the insulation inside, that was too long. He turned quickly to expose another part of himself to the sunlight. He knew abstractedly that the metal underfoot would sear bare flesh that touched it. A few yards away, in the shadow, the metal of the hull would be cold enough to freeze hydrogen. But here it was fiercely hot. It would melt solder. It might—

Mike was fumbling tin cans out of the net bag from which Haney had been throwing them away. He was a singular small figure, standing on shining steel, looking at one tin can after another and impatiently putting them aside.

He found one that seemed to suit him. It was a large can. He knelt with it, pressing a part of it to the hot metal of the satellite's hull. A moment later he was ripping it apart. The solder had softened. He unrolled a sort of cylinder, then bent again, using the curved inner surface to concentrate the intolerable sunshine.

Joe caught his breath at the implication. Concentrated sunshine can be incredibly hot. Starting with unshielded, empty-space sunshine, practically any imaginable temperature is possible with a large enough mirror. Mike didn't have a concave mirror. He had only a cylindrical one. He couldn't reflect light to a point, but only to a line. Mike couldn't hope to do more than double or triple the temperature of a given spot. But considering what he wore on his back—!

Joe made his way clumsily to the spot where Mike now gesticulated to Haney, trying to convey his meaning by gestures since Sanford would overhear any spoken word.

"I get it, Mike," said Joe. "I'll help." He added: "Chief! You watch Sanford. The rest of you try to flatten out some tin cans or find some with flat round ends!"

He reached the spot where Mike bent over the plating. His hand moved to cast a shadow where the light had played.

"I need more reflectors," Mike said brusquely, "but we can do it!"

Joe beckoned. There were more, hurried clankings. Space-suited figures gathered about.

The Platform rolled on through space. Where it was bright it was very, very bright, and where it was dark it was blackness. Off in emptiness the many-colored mass of Earth shone hugely, rolling past. Innumerable incurious stars looked on. The sun flamed malevolently. The moon floated abstractedly far away.

Mike was bent above a small round airlock door. He had a distorted half-cylinder of sheet tin between his space-gloved hands. It reflected a line of intensified sunlight to the edge of the airlock seal. Haney ripped fiercely at other tin cans. Joe held another strip of polished metal. It focused crudely—very crudely—on top of Mike's line of reflected sunshine. Someone else held the end of a tin can to reflect more sunshine. Someone else had a larger disk of tin.

They stood carefully still. It looked completely foolish. There were six men in frozen attitudes, trying to reflect sunshine down to a single blindingly-bright spot on an airlock door. They seemed breathlessly tense. They ignored the glories of the firmament. They were utterly absorbed in trying to make a spot of unbearable brightness glow more brightly still.

Mike moved his hand to cast a shadow. The steel was a little more than red-hot for the space of an inch. It would not melt, of course. It could not. And they had no tools to bend or pierce the presumably softened metal. But Mike said fiercely:

"Keep it hot!"

He squirmed. His space suit was fabric, like the rest, but it had been cut down to permit him to use it. It was bulkier on him than the suits of the others. He shifted his shoulder pack. The brass valve-nipple by which the oxygen tank was filled....

He jammed a ragged fragment of tin in place. He pressed down fiercely. A blazing jet of fierce, scintillating, streaking sparks leaped up from the spot where the metal glowed brightly. A hollow in the metal plate appeared. The metal disintegrated in gushing flecks of light....

White-hot iron in pure oxygen happens to be inflammable. Iron is not incombustible at all. Powdered steel, ground fine enough, will burn if simply exposed to air. Really fine steel wool will make an excellent blaze if a match is touched to it. White-hot iron, with a jet of oxygen played upon it, explodes to steaming sparks. Technically, Mike had used the perfectly well-known trick of an oxygen lance to pierce the airlock door, let the air out of the lock, and so allow the outer door to be opened.

There was a rush of vapor. The door was drilled through. Haney picked Mike up bodily, Joe heaved the door open, and Haney climbed into it, practically carrying Mike by the scruff of the neck. Joe panted, "Plug the hole from the inside. Sit on it if you have to!" and slammed the door shut.

They waited. Sanford's voice came in the ear-phones. It was higher in pitch than it had been.

"You fools!" he raged. "It's useless! It's stupid to do useless things! It's stupid to do anything at all—"

There were sudden scuffling clankings. Joe swung about. The Chief and Sanford were struggling. Sanford flailed his arms about, trying to break the Chief's faceplate while he screamed furious things about futility.

The Chief got exactly the hold he wanted. He lifted Sanford from the metal deck. He could have thrown him away to emptiness, then, but he did not.

He set Sanford in mid-space as if upon a shelf. The raging man hung in the void an exact man-height above the Platform's surface. The Chief drew back and left him there, Sanford could writhe there for a century before the Platform's infinitesimal gravity brought him down.

"Huh!" said the Chief wrathfully. "How's Haney and Mike making out?"

Almost on the instant, twenty yards away, a tiny airlock door thrust out from the surface of glittering metal, and helmet and antenna appeared.

"You guys can come in now," said Haney's voice in Joe's headphones. "It's all okay. Mike's pumping out the other locks too, so you can come in at any of 'em."

The space-suited figures clumped loudly to airlock doors. There were a dozen or more small airlocks in various parts of the hull, besides the great door to admit supply ships. The Chief growled and moved toward Sanford now raging like the madman his helplessness made him.

"No," said Joe shortly. "He'd fight again. Go inside. That's an order, Chief."

The Chief grunted and obeyed. Joe went to the nearest airlock and entered the great steel hull.

Sanford floated in emptiness, two yards from the Space Platform he would have turned into a derelict. He did not move farther away. He did not fall toward it. There was nobody to listen to him. He cried out in blood-curdling fury because other men were smarter than he was. Other men had solved problems he could not solve. Other men were his superiors. He screamed his rage.

Presently the Platform revolved slowly beneath him. It was turned, of course, by the monster gyros which in turn were controlled by the pilot gyros Joe and Haney and the Chief and Mike had repaired when saboteurs smashed them.

The Platform rotated sedately. A great gap appeared in it. The door of the supply ship lock moved until Sanford, floating helplessly, was opposite its mouth.

A rod with a rounded object at its end appeared past the docked supply ship. It reached out and touched Sanford's helmet. It was the magnetic grapple which drew space ships into their dock.

It drew Sanford, squirming and streaming, into the great lock. The outer doors closed. Before air was admitted to the inside, Sanford went suddenly still.

When they took him out of his suit he was apparently unconscious. He could not be roused. Freed, he drew his knees up to his chin in the position in which primitive peoples bury their dead. He seemed to sleep. Brent examined him carefully.

"Catatonia," he said distastefully. "He spent his life thinking he was smarter than anybody else—smarter, probably, than all the universe. He believed it. He couldn't face the fact that he was wrong. He couldn't stay conscious and not know it. So he's blacked out. He refuses to be anything unless he can be smartest. We'll have to do artificial feeding and all that until we can get him down to Earth to a hospital." He shrugged.

"We'd better report this down to Earth," Joe said. "By the way, better not describe our screen of tin cans on radio waves. Not even microwaves. It might leak. And we want to see if it works."

Just forty-two hours later they found out that it did work. A single rocket came climbing furiously out from Earth. It came from the night-side, and they could not see where it was launched, though they could make excellent guesses. They got a single guided missile ready to crash it if necessary.

It wasn't necessary. The bomb from Earth detonated 300 miles below the artificial satellite. Its proximity fuse, sending out small radar-type waves, had them reflected back by an empty sardine can thrown away from the Platform by Mike Scandia forty-some hours ago. The sardine can had been traveling in its own private orbit ever since. The effect of Mike's muscles had not been to send it back to Earth, but to change the center of the circular orbit in which it floated. Sometimes it floated above the Platform—that was on one side of Earth—and sometimes below it. It was about 300 miles under the Platform when it reflected urgent, squealing radar frequency waves to a complex proximity fuse in the climbing rocket. The rocket couldn't tell the difference between a sardine can and a Space Platform.

It exploded with a blast of pure brightness like that of the sun.

The Platform went on its monotonous round about the planet from which it had risen only weeks before. Sanford was strapped in a bunk and fed through a tube, and on occasion massaged and variously tended to keep him alive. The men on the Platform worked. They made telephoto maps of Earth. They took highly magnified, long-exposure photographs of Mars, pictures that could not possibly be made with such distinctness from the bottom of Earth's turbulent ocean of air.

There was a great deal of official business to be done. Weather observations of the form and distribution of cloud masses were an important matter. The Platform could make much more precise measurements of the solar constant than could be obtained below. The flickering radar was gathering information for studies of the frequency and size of meteoric particles outside the atmosphere. There was the extremely important project for securing and sealing in really good vacua in various electronic devices brought up by Joe and his crew in the supply ship.

But sometimes Joe managed to talk to Sally.

It was very satisfying to see her on the television screen in personal conversation. Their talk couldn't be exactly private, because it could be picked up elsewhere. It probably was. But she told Joe how she felt, and she wanted to read him the newspaper stories based on the reports Brent had sent down. Brent was in command of the Platform now that Sanford lay in a resolute coma in his bunk. But Joe discouraged such waste of time.

"How's the food?" asked Sally. "Are you people getting any fresh vegetables from the hydroponic garden?"

They were, and Joe told her so. The huge chamber in which sun-lamps glowed for a measured number of hours in each twenty-four produced incredibly luxuriant vegetation. It kept the air of the ship breathable. It even changed the smell of it from time to time, so that there was no feeling of staleness.

"And the cooking system's really good?" she wanted to know. Sally was partly responsible for that, too. "And how about the bunks?"

"I sleep now," Joe admitted.

That had been difficult. It was possible to get used to weightlessness while awake. One would slip, sometimes, and find himself suddenly tense and panicky because he'd abruptly noticed all over again that he was falling. But—and yet again Sally was partly responsible—the bunks were designed to help in that difficulty. Each bunk had an inflatable top blanket. One crawled in and settled down, and turned the petcock that inflated the cover. Then it held one quite gently but reassuringly in place. It was possible to stir and to turn over, but the feeling of being held fast was very comforting. With a little care about what one thought of before going to sleep, one could get a refreshing eight hours' rest. The bunks were luxury.

Sally said: "The date and time's a secret, of course, because it might be overheard, but there'll be another ship up before too long. It's bringing landing rockets for you to come back with."

"That's good!" said Joe. It would feel good to set foot on solid ground again. He looked at Sally and said eagerly, "We've got a date the evening I get back?"

"We've got a date," she said, nodding.

But it couldn't very well be a definite date. There were people with ideas that ran counter to plans for Joe to get back to Earth and a date with Sally Holt. The Space Platform was not admired uniformly by all the nations of Earth. The United States had built it because the United Nations couldn't, and one of the attractions of the idea had been that once it got out to space and was armed, peace must reign upon Earth because it could smack down anybody who made war.

The trouble was that it wasn't armed well enough. Six guided missiles couldn't defend it indefinitely. It looked as helpless as isolated Berlin did before the first airlift proved what men and planes could do in the way of transport. And the Platform's enemies didn't intend for it to be saved by a rocketlift. They would try to smash it before such a lift could get started.

A week after Joe got to it with the guided missiles, three rockets attacked. They went up from somewhere in the middle of the Pacific. One blew up 250 miles below the Platform. Another detonated 190 miles away. For safety's sake the third was crashed—at the cost of one guided missile—when it had come within 50 miles.

The screen of tin cans worked, but it wasn't thick enough. The occupants of the Platform went about hunting for sheet metal that could be spared. They pulled out minor partitions here and there, and went out on the surface and threw away thousands of small glittering scraps of metal in all directions.

Two weeks later, there was another attack. It could be calculated that Joe couldn't have carried up more than six guided missiles. There might be as few as two of them left. So eight rockets came up together—and the first of them went off 400 miles from the Platform. Only one got as close as 200 miles. No guided missiles were expended in defense.

The Platform's enemies tried once more. This time the rockets arched up above the Platform's orbit and dived on the satellite from above. There were two of them. They went off at 180 and 270 miles from the Platform. Joe's trash screen would not work on Earth, but in space it was an adequate defense against anything equipped with proximity fuses. It could be assumed that in a full-scale space-war nuts, bolts, rusty nails and beer bottle caps would become essential military equipment.

Three days after this last attack, a second supply ship took off from Earth. Lieutenant Commander Brown was a passenger. Its start was just like the one Joe's ship had made. Pushpots lifted it, jatos hurled it on, and then the furious, flaming take-off rockets drove it valiantly out toward the stars.

Joe's ship had been moved out of the landing lock and was moored against the Platform's hull. The second ship made contact in two hours and seventeen minutes from take-off. It arrived with its own landing rockets intact, and it brought a set of forty-foot metal tubes for Joe's ship to get back to Earth with. But those landing rockets and Lieutenant Commander Brown constituted all its payload. It couldn't bring up anything else.

And Lieutenant Commander Brown called a very formal meeting in the huge living space at the Platform's center. He stood up grandly in full uniform—and had to hook his feet around a chair leg to keep from floating absurdly in mid-air. This detracted slightly from the dignity of his stance, but not from the official voice with which he read two documents aloud.

The first paper detached Lieutenant Commander Brown from his regular naval duties and assigned him pro tem to service with the Space Exploration Project. The second was an order directing him to take command and assume direction of the Space Platform.

Having read his orders, he cleared his throat and said cordially, "I am honored to serve here with you. Frankly, I expect to learn much from you and to have very few orders to give. I expect merely to exercise such authority as experience at sea has taught me is necessary for a tight and happy ship. I trust this will be one."

He beamed. Nobody was impressed. It was perfectly obvious that he'd simply been sent up to acquire experience in space for later naval use, and that he'd been placed in command because it was unthinkable that he serve under anyone without official rank and authority. And he quite honestly believed that his coming, with experience in command, was a blessing to the Platform. In fact, there was no danger that this commander of the Platform would crack up under stress as Sanford had.

But it was too bad that he hadn't brought some long-range guided missiles with him.

Joe's ship had brought up twenty tons of cargo and twenty tons of landing rockets. The second ship brought up twenty tons of landing rockets for Joe, and twenty tons of landing rockets for itself. That was all. The second trip out to the Space Platform was a rescue mission and nothing else. Arithmetic wouldn't let it be anything else. And there couldn't be any idea of noble self-sacrifice and staying out at the Platform, either, because only four ships like Joe's had been begun, and only two were even near completion. Joe's had taken off the instant it was finished. The second had done the same. The second pair of spaceships wouldn't be ready for two months or more. The ships that could be used had to be used.

So, only thirty-six hours after the arrival of the second rocketship at the Platform, the two of them took off together to return to Earth. Joe's ship left the airlock first. Sanford was loaded in the cabin of the other ship as cargo. Lieutenant Commander Brown stayed out at the Platform to replace him.

Obviously, in order to get back to Earth they headed away from it in fleet formation. They pointed their rounded noses toward the Milky Way.

The upward course was an application of the principle that made the screen of tin cans and oddments remain about the Platform. Each of those small objects had had the Platform's own velocity and orbit. Thrown away from it, the centers of their orbits changed. In theory, the center of the Platform's orbit was the center of Earth. But the centers of the orbits of the thrown-away objects were pushed a few miles—twenty—fifty—a hundred—away from the center of Earth.

The returning space ships also had the orbit and speed of the Platform. They wanted to shift the centers of their orbits by very nearly 4,000 miles, so that at one point they would just barely graze Earth's atmosphere, lose some speed to it, and then bounce out to empty space again before they melted. Cooled off, they'd make another grazing bounce. After eight such bounces they'd stay in the air, and the stubby fins would give them a sort of gliding angle and controllability, while the landing rockets would let them down to solid ground. Or so it was hoped.

Meanwhile they headed out instead of in toward Earth. They went out on their steering-rockets only, using the liquid fuel that had not been needed for course correction on the way out. At 4,000 miles up, the force of gravity is just one-fourth of that at the Earth's surface. It still exists; it is merely canceled out in an orbit. The ships could move outward at less cost in fuel than they could move in.

So they went out and out on parallel courses, and the Platform dwindled behind them. Night flowed below until the hull of the artificial satellite shone brightly against a background of seeming sheer nothingness.

The twilight zone of Earth's shadow reached the Platform. It glowed redly, glowed crimson, glowed the deepest possible color that could be seen, and winked out. The ships climbed on, using their tiny steering rockets.

Nothing happened. The ships drew away from each other for safety. They were 50, then 60 miles apart. One glowed red and vanished in the shadow of the Earth. The other was extinguished in the same way. Then they went hurtling through the blackness of the night side of Earth. Microwaves from the ground played upon them—radar used by friend and foe alike—and the friendly radar guided tight-beam communicator waves to them with comforting assurance that their joint course and height and speed were exactly the calculated optimum. But they could not be seen at all.

When they appeared again they were still farther out from Earth than the Platform's orbit, but no farther from each other. And they were descending. The centers of their orbits had been displaced very, very far indeed.

Going out, naturally, the ships had lost angular speed as they gained in height. Descending, they gained in angular velocity as they lost height. They were not quite 30 miles apart as they sped with increasing, headlong speed and rushed toward the edge of the world's disk. When they were only 2,000 miles high, the Earth's surface under them moved much faster than it had on the way up. When they were only 1,000 miles high, the seas and continents seemed to flow past like a rushing river. At 500 miles, mountains and plains were just distinguishable as they raced past underneath. At 200 miles there was merely a churning, hurtling surface on which one could not focus one's eyes because of the speed of its movement.

They missed the solid surface of Earth by barely 40 miles. They were moving at a completely impossible speed. The energy of their position 4,000 miles high had been transformed into kinetic energy of motion. And at 40 miles there is something very close to a vacuum, compared to sea-level. But compared to true emptiness, and at the speed of meteors, the thin air had a violent effect.

A thin humming sound began. It grew louder. The substance of the ship was responding to the impact of the thin air upon it. The sound rose to a roar, to a bellow, to a thunderous tumult. The ship quivered and trembled. It shook. A violent vibration set up and grew more and more savage. The whole ship shook with a dreadful persistence, each vibration more monstrous, more straining, more ominous than before.

The four in the space ship cabin knew torture. Weight returned to them, weight more violent than the six gravities they had known for a bare fourteen seconds at take-off. But that, at least, had been smoothly applied. This was deceleration at a higher figure yet, and accompanied by the shaking of bodies which weighed seven times as much as ever before—and bodies, too, which for weeks past had been subject to no weight at all.

They endured. Nothing at all could be done. At so many miles per second no possible human action could be determined upon and attempted in time to have any effect upon the course of the ship. Joe could see out a quartzite port. The ground 40 miles below was merely a blur. There was a black sky overhead, which did not seem to stir. But cloud-masses rushed at express-train speed below him, and his body weighed more than half a ton, and the ship made the sound of innumerable thunders and shook, and shook and shook....

And then, when it seemed that it must fly utterly to pieces, the thunder diminished gradually to a bellow, and the bellow to a roar, and the roaring.... And the unthinkable weight oppressing him grew less.

The Earth was farther away and moving farther still. They were 100 miles high. They were 200 miles high....

There was no longer any sound at all, except their gaspings for breath. Their muscles had refused to lift their chests at all during the most brutal of the deceleration period.

Presently Joe croaked a question. He looked at the hull-temperature indicators. They were very, very high. He found that he was bruised where he had strapped himself in. The places where each strap had held his heavy body against the ship's vibrations were deeply black-and-blue.

The Chief said thickly: "Joe, somehow I don't think this is going to work. When do we hit again?"

"Three hours plus or minus something," said Joe, dry-throated. "We'll hear from the ground."

Mike said in a cracked voice: "Radar reports we went a little bit too low. They think we weren't tilted up far enough. We didn't bounce as soon as we should."

Joe unstrapped himself.

"How about the other ship?"

"It did better than we did," said Mike. "It's a good 200 miles ahead. Down at the Shed, they're recalculating for us. We'll have to land with six grazes instead of eight. We lost too much speed."

Joe went staggering, again weightless, to look out a port for the other ship. He should have known better. One does not spot an eighty-foot space ship with the naked eye when it is 200 miles away.

But he saw something, though for seconds he didn't know what it was.

Now the little ship was 300 miles high and still rising. Joe was dazed and battered by the vibration of the ship in the graze just past. The sister space ship hadn't lost speed so fast. It would be traveling faster. It would be leaving him farther behind every second. It was rising more sharply. It would rise higher.

Joe stared numbly out of a port, thinking confusedly that his hull would be dull red on its outer surface, though the heating had been so fast that the inner surfaces of the plating might still be cold. He saw the vast area which was the curve of the edge of the world. He saw the sunlight upon clouds below and glimpses of the surface of the Earth itself.

And he saw something rising out of the mists at the far horizon. It was a thread of white vapor. The other rocketship was a speck, a mote, invisible because of its size and distance. This thread of vapor was already 100 miles long, and it expanded to a column of whiteness half a mile across before it seemed to dissipate. It rose and rose, as if following something which sped upward. It was a rocket trail. The violence of its writhings proved the fury with which the rocket climbed.

It was on its way to meet the other space ship.

It did. Joe saw the thread of vapor extend and grow until it was higher than he was. He never saw the other ship, which was too small. But he saw the burst of flame, bright as the sun itself, which was the explosion of a proximity fuse bomb. He knew, then, that nothing but incandescent, radioactive gas remained of the other ship and its crew.

Then he saw the trail of the second rocket. It was rising to meet him.



5

The four of them watched through the ports as the thread of vapor sped upward. They hated the rocket and the people who had built it. Joe said between his teeth, "We could spend our landing-rockets and make it chase us, but it'll have fuel for that!"

The Chief muttered in Mohawk. The words sounded as if they ought to have blue fire at their edges and smell of sulphur. Mike the midget said crackling things in his small voice. Haney stared, his eyes burning.

Their ship was a little over 400 miles up, now. The rocket was 100 or better. The rendezvous would be probably 200 miles ahead and correspondingly higher. The rocket was accelerating furiously. It had farther to travel, but its rate of climb was already enormous and it increased every second.

The ship could swing to right or left on steering rockets, but the war rocket could swerve also. It was controlled from the ground. It did not need to crash the small ship from space. Within a limited number of miles the blast of its atomic warhead would vaporize any substance that could exist. And of course the ship could not turn back. Even the expenditure of all its landing-rockets could not bring twenty tons of ship to a halt. They could speed it up, so it would pass the calculated meeting place ahead of the war rocket. But the bomb would simply follow in a stern chase. In any case, the ship could not stop.

But neither could the rocket.

Joe never knew how he saw the significance of that fact. On land or sea, of course, an automobile or a ship moves in the direction in which it is pointed. Even an airplane needs to make only minor corrections for air currents which affect it. But an object in space moves on a course which is the sum of all its previous speeds and courses. Joe's ship was moving eastward above the Earth at so many miles per second. If he drove north—at a right angle to his present course—the ship would not cease to move to the east. It would simply move northward in addition to moving east. If the rocket from Earth turned north or east it would continue to move up and merely add the other motion to its vertical rise.

Joe stared at the uncoiling thread of vapor which was the murder rocket's trail. He hated it so fiercely that he wanted to escape it even at the cost of destruction, merely to foil its makers. At one moment, he was hardly aware of anything but his own fury and the frantic desire to frustrate the rocket at any cost. The next instant, somehow, he was not angry at all. Because somehow his brain had dredged up the fact that the war rocket could no more turn back than he could—and he saw its meaning.

"Mike!" he snapped sharply. "Get set! Report what we do! Everybody set for acceleration! Steering rockets ready, Chief! Get set to help, Haney! I don't know whether we'll get out of this alive, but we'd better get into our space suits."

Then he literally dived back to his acceleration chair and strapped in in feverish haste. The ship was then a quarter of the way to the meeting place and the rocket had very much farther to go. But it was rising faster.

The ship's gyros whined and squealed as Joe jammed on their controls. The little ship spun in emptiness. Its bow turned and pointed down. The steering rockets made their roarings.

Joe found himself panting. "The—rocket's rising faster—than we are. It's been gaining—altitude maybe—two minutes. It's lighter than when—it started but—it can't stop—less than a minute, anyhow so we duck under it——"

He did not make computations. There was no time. The war rocket might have started at four or five gravities acceleration, but it would speed up as its fuel burned. It might be accelerating at fifteen gravities now, and have an attained velocity of four miles a second and still increasing. If the little ship ducked under it, it could not kill that rate-of-climb in time to follow in a stern chase.

"Haney!" panted Joe. "Watch out the port! Are we going to make it?"

Haney crawled forward. Joe had forgotten the radar because he'd seen the rocket with his own eyes. It seemed to need eyes to watch it. Mike spoke curtly into the microphone broadcasting to ground. He was reporting each action and order as it took place and was given. There was no time to explain anything. But Mike thought of the radar. He watched it.

It showed the vast curve of Earth's surface, 400 miles down. It showed a moving pip, much too much nearer, which was the war rocket. Mike made a dot on the screen with a grease pencil where the pip showed. It moved. He made another dot. The pip continued to move. He made other dots.

They formed a curving line—curved because the rocket was accelerating—which moved inexorably toward the center of the radar screen. The curve would cut the screen's exact center. That meant collision.

"Too close, Joe!" said Mike shrilly. "We may miss it, but not enough!"

"Then hold fast," yelled Joe. "Landing rockets firing, three—two—one!"

The bellowing of the landing-rockets smote their ears. Weight seized upon them, three gravities of acceleration toward the rushing flood of clouds and solidity which was the Earth. The ship plunged downward with all its power. It was intolerable—and ten times worse because they had been weightless so long and were still shaken and sore and bruised from the air-graze only minutes back.

Mike took acceleration better than the others, but his voice was thin when he gasped, "Looks—like this does it, Joe!" Seconds later he gasped again, "Right! The rocket's above us and still going away!"

The gyros squealed again. The ship plunged into vapor which was the trail of the enemy rocket. For an instant the flowing confusion which was Earth was blotted out. Then it was visible again. The ship was plunging downward, but its sidewise speed was undiminished and much greater than its rate of fall.

"Mike," panted Joe. "Get the news out. What we did—and why. I'm—going to turn the ship's head back on our—course. We can't slow enough but—I'd rather crash on Earth than let them blast us——"

The ship turned again. It pointed back in the direction from which it had come. With the brutal sternward pressure produced by the landing-rockets, it felt as if it were speeding madly back where it had come from. It was the sensation they'd felt when the ship took off from Earth, so long before. But then the cloud masses and the earth beneath had flowed toward the ship and under it. Now they flowed away. The appearance was that of an unthinkably swift wake left behind by a ship at sea. The Earth's surface fled away and fled away from them.

"Crazy, this!" Joe muttered thickly. "If the ship were lighter—or we had more power—we could land! I'm sorry, but I'd rather——"

Haney turned his head from where he clung near the bow-ports. His features changed slowly as he talked because of acceleration-driven blood engorging his lips and bloating his cheeks. After one instant he closed his eyes fiercely. They felt as if they would pop out of his head. He gasped, "Yes! Get down to air-resistance. A chance—not good but a chance—ejection seats—with space suits—might make it...."

He began to let himself back toward his acceleration chair. He could not possibly have climbed forward. It was a horrible task to let himself down, with triple his normal weight pulling at him and after the beating taken a little while ago.

Sweat stood out on his skin as he lowered himself sternward. Once his grip on a hand-line slipped and he had to sustain the drag of nearly six hundred pounds by a single hand and arm. It would not be a good idea to fall at three gravities.

The landing rockets roared and roared, and Joe tilted the bow down a little farther, so that the streaming flood of clouds drew nearer.

Haney got to his acceleration chair. He let himself into it and his eyes closed.

Mike's sharp voice barked: "What's the chance, Haney?"

Haney's mouth opened, and closed, and opened again. "Rocket flames," he gasped, "pushed back—wind—splash on hull—may melt—lighten weight—hundred to one against——"

The odds were worse than that. The ship couldn't land because its momentum was too great for the landing rockets to cancel out. If it had weighed five tons instead of twenty, landing might have been possible. Haney was saying that if the ship were to be lowered into air while rushing irresistibly sternward despite its rockets, that the rocket flames might be splashed out by the wind. Instead of streaking astern in a lance-like shape, they might be pushed out like a rocket blast when it hits the earth in a guided missile take-off. Such a blast spreads out flat in all directions. Here the rocket flames might be spread by wind until they played upon the hull of the ship. If they did, they might melt it as they melted their own steel cases in firing. And three-fourths or more of the hull might be torn loose from the cabin bow section. So much was unlikely, but it was possible.

The impossible odds were that the four could survive even if the cabin were detached. They were decelerating at three gravities now. If part of the ship burned or melted or was torn away, the rocket thrust might speed the cabin up to almost any figure. And there is a limit to the number of gravities a man can take, even in an acceleration chair.

Nevertheless, that was what Haney proposed. They were due to be killed anyhow. Joe tried it.

He dived into atmosphere. At 60 miles altitude a thin wailing seemed to develop without reason. At 40 miles, the ship had lost more than two miles per second of its speed since the landing-rockets were ignited, and there was a shuddering in all its fabric—though because of the loss of speed it was not as bad as the atmosphere-graze. At 30 it began to shake and tremble. At 25 miles high there was as horrible a vibration and as deadly a deceleration as at the air-graze. At 12 miles above the surface of the Earth the hull temperature indicators showed the hind part of the hull at red heat. The ship happened to be traveling backward at several times the speed of sound, and air could not move away from before it. It was compressed to white heat at the entering surface, and the metal plating went to bright red heat at that point. But the hull just aft of the rocket mouths was hotter still. There the splashing rocket flames bathed it in intolerable incandescence. Hull plates, braces and beams glared white——

The tip of the tail caved in. The ship's empty cargo space was instantly filled with air at intolerable pressure and heat.

The hull exploded outward where the rocket flames played. There was a monstrous, incredible jerking of the cabin that remained. That fraction of the ship received the full force of the rocket thrust. They could decelerate it at a rate of fifteen gravities or more.

They did.

Joe lost consciousness as instantly and as peacefully as if he had been hit on the jaw.

An unknown but brief time later, he found himself listening with a peculiar astonishment. The rockets had burned out. They had lasted only seconds after the separation of the ship into two fragments. Radars on the ground are authority for this. Those few seconds were extremely important. The cabin lost an additional half-mile per second of velocity, which was enough to make the difference between the cabin heating up too, and the cabin being not quite destroyed.

The cabin remnant was heavy, of course, but it was an irregular object, some twenty feet across. It was below orbital velocity, and wind-resistance slowed it. Even so, it traveled 47 miles to the east in falling the last 10 miles to Earth. It hit a hillside and dug itself a 70-foot crater in the ground.

But there was nobody in it, then. A little over a month before, it had seemed to Joe that ejection seats were the most useless of all possible pieces of equipment to have in a space ship. He'd been as much mistaken as anybody could be. With an ejection seat, a jet pilot can be shot out of a plane traveling over Mach one, and live to tell about it. This crumpling cabin fell fast, but Joe stuffed Mike in an ejection seat and shot him out. He and the Chief dragged Haney to a seat, and then the Chief shoved Joe off—and the four of them, one by one, were flung out into a screaming stream of air. But the ribbon-parachutes did not burst. They nearly broke the necks of their passengers, but they let them down almost gently.

And it was quite preposterous, but all four landed intact. Mike, being lightest and first to be ejected, came down by himself in a fury because he'd been treated with special favor. The Chief and Joe landed almost together. After a long time, Joe staggered out of his space suit and harness and tried to help the Chief, and they held each other up as they stumbled off together in search of Haney.

When they found him he was sleeping heavily, exhausted, in a canebrake. He hadn't even bothered to disengage his parachute harness or take off his suit.



6

A good deal of that landing remained confused in Joe's mind. While it was going on he was much too busy to be absorbing impressions. When he landed, he was as completely exhausted as anybody wants to be. It was only during the next day that he even tried to sort out his recollections.

Then he woke up suddenly, with a muffled roaring going on all about him. He blinked his eyes open and listened. Presently he realized what the noise was, and wondered that he hadn't realized before. It was the roaring of the motors of a multi-engined plane. He knew, without remembering the details at the moment, that he and the other three were on a plane bound across the Pacific for America. He was in a bunk—and he felt extraordinarily heavy. He tried to move, and it was an enormous effort to move his arm. He struggled to turn over, and found straps holding his body down.

He fumbled at them. They had readily releasable clasps, and he loosened them easily. After a bit he struggled to sit upright. He was horribly heavy or horribly weak. He couldn't tell which. And each separate muscle in his whole body ached. Twinges of pain accompanied every movement. He sat up, swaying a little with the slow movements of the plane, and gradually, things came back.

The landing in the ribbon-chute. They'd come down somewhere on the west coast of India, not too far from the sea. He remembered crashing into the edge of a thin jungle and finding the Chief, and the two of them searching out Haney and stumbling to open ground. After laying out a signal for air searchers, they went off into worn-out slumber while they waited.

He remembered that there'd been a patrol of American destroyers in the Arabian Sea, as everywhere under the orbit of the Platform. Their radar had reported the destruction of one space ship and the frantic diving of the other, its division into two parts, and then the tiny objects, which flew out from the smaller cabin section, which had descended as only ejection-seat parachutes could possibly have done. Two destroyers steamed onward underneath those drifting specks, to pick them up when they should come down. But the other nearby destroyers had other business in hand.

The two trailing destroyers reached Goa harbor within hours of the landing of the four from space. A helicopter found the first three of them within hours after that. They were twenty miles inland and thirty south from Goa. Mike wasn't located until the next day. He'd been shot out of the ship's cabin earlier and higher; he was lighter, and he'd floated farther.

But things—satisfying things—had happened in the interval. Sitting almost dizzily on the bunk in the swiftly roaring plane while blood began sluggishly to flow through his body, Joe remembered the gleeful, unofficial news passed around on the destroyers. They waited for Mike to be brought in. But they rejoiced vengefully.

The report was quite true, but it never reached the newspapers. Nobody would ever admit it, but the rockets aimed at the returning space ships had been spotted by Navy radar as they went up from the Arabian Sea. And the ships of the radar patrol couldn't do anything about the rockets, but they could and did converge savagely upon the places from which they had been launched. Planes sped out to spot and bomb. Destroyers arrived.

Somewhere there was a navy department that could write off two modern submarines with rocket-launching equipment, last heard from west of India. American naval men would profess bland ignorance of any such event, but there were acres of dead fish floating on the ocean where depth-bombs had hunted down and killed two shapes much too big to be fish, which didn't float when they were killed and which would never report back how they'd destroyed two space ships. There'd be seagulls feasting over that area, and there'd be vague tales about the happening in the bazaars of Hadhramaut. But nobody would ever admit knowing anything for certain.

But Joe knew. He got to his feet, wobbling a little bit in the soaring plane. He ached everywhere. His muscles protested the strain of holding him erect. He held fast, summoning strength. Before his little ship broke up he'd been shaken intolerably, and his body had weighed half a ton. Where his safety-belt had held him, his body was one wide bruise. There'd been that killing acceleration when the ship split in two. The others—except Mike—were in as bad a case or worse. Haney and the Chief were like men who'd been rolled down Mount Everest in a barrel. All of them had slept for fourteen hours straight before they even woke up for food. Even now, Joe didn't remember boarding this plane or getting into the bunk. He'd probably been carried in.

Joe stood up, doggedly, until enough strength came to him to justify his sitting down again. He began to dress. It was astonishing how many places about his body were sore to the touch. It was startling how heavy his arms and legs felt, and how much of an effort even sitting erect was. But he began to remember Mike's adventure, and managed to grin feebly. It was the only thing worth a smile in all the things that had happened.

Because Mike's landing had been quite unlike the others. Joe and the Chief landed near the edge of a jungle. Haney landed in a canebrake. But Mike came floating down from the sky, swaying splendidly, into the estate of a minor godling.

He was relatively unharmed by the shaking-up he'd had. The strength of muscles depends on their cross-section, but their weight depends on their volume. The strength of a man depends on the square of his size, but his weight on the cube. So Mike had taken the deceleration and the murderous vibration almost in his stride. He floated longer and landed more gently than the rest.

Joe grinned painfully at the memory of Mike's tale. He'd come on board the rescue destroyer in a towering, explosive rage. When his ribbon-parachute let him down out of the sky, it deposited him gently on ploughed fields not far from a small and primitive Hindu village. He'd been seen to descend from the heavens. He was a midget—not as other men—and he was dressed in a space suit with glittering metal harness.

The pagan villagers greeted him with rapture.

When the searching-party found Mike, they were just in time to prevent a massacre—by Mike. Adoring natives had seized upon him, conveyed him in high state to a red mud temple, seemingly tried to suffocate him with evidences of their pride and joy at his arrival, and dark-skinned maidens were trying hopefully to win his approval of their dancing. But the rescue-party found him with a club in his hand and blood in his eye, setting out furiously to change the tone of his reception.

Joe still didn't know all the details, but he tried to concentrate on what he did know as he put his uniform on again. He didn't want to think how little it meant, now. The silver space ship badge didn't mean a thing, any more. There weren't any more space ships. The Platform wasn't a ship, but a satellite. There'd never been but two ships. Both had ceased to exist.

Joe walked painfully forward in the huge, roaring plane. The motors made a constant, humming thunder in his ears. It was not easy to walk. He held on to handholds as he moved. But he progressed past the bunk space. And there was Mike, sitting at a table and stuffing himself with good honest food. There was a glass port beside him, and Joe caught a glimpse of illimitable distances filled with cloud and sky and sea.

Mike nodded. He didn't offer to help Joe walk. That wouldn't have been practical. He waited until Joe sank into a seat opposite.

"Good sleep?" asked Mike.

"I guess so," said Joe. He added ruefully, "It hurts to nod, and I think it would hurt worse to shake my head. What's the matter with me, Mike? I didn't get banged up in the landing!"

"You got banged up before you landed," said Mike. "Worse than that, you spent better than six weeks out of gravity, where in an average day you took less actual exercise than a guy in bed with two broken legs!"

Joe eased himself back into his chair. He felt about 600 years old. Somebody poked a head into view and withdrew it. Joe lifted his arm and regarded it.

"Weighty! I guess you're right, Mike."

"I know I'm right!" said Mike. "If you spent six weeks in bed you'd expect to feel wobbly when you tried to walk. Up on the Platform you didn't even use energy to stand up! We didn't realize it, but we were living like invalids! We'll get our strength back, but next time we'll take measures. Huh! Take a trip to Mars in free fall, and by the time a guy got there his muscles'd be so flabby he couldn't stand up in half-gravity! Something's got to be done about that, Joe!"

Joe said sombrely, "Something's got to be done about space ships before that comes up again!"

Somebody appeared with a tray. There was food on it. Smoking hot food. Joe looked at it and knew that his appetite, anyhow, was back to Earth normal.

"Thanks!" he mumbled appreciatively, and attacked the food.

Mike drank his coffee. Then he said, "Joe, do you know anything about powder metallurgy?"

Joe shrugged. It hurt. "Powder metallurgy? Yes, I've seen it used, at my father's plant. They've made small precision parts with it. Why?"

"D'you know if anybody ever made a weld with it?" asked Mike.

Joe chewed. Then he said:

"I think so. Yes. At the plant they did. They had trouble getting the surfaces properly cleaned for welding. But they managed it. Why?"

"One more question," said Mike tensely. "How much Portland cement is used to make a cubic yard of concrete?"

"I wouldn't know," admitted Joe. "Why? What's all this about?"

"Haney and the Chief. Those two big apes have been kidding me—as long as they could stay awake—for what happened to me when I landed. Those infernal savages—" Mike seethed. "They got my clothes off and they had me smeared all over with butter and forty-'leven necklaces around my neck and flowers in my hair! They thought I was some kind of heathen god! Hanuman, somebody told me. The Hindu monkey-god!" He raged. "And those two big apes think it's funny! Joe, I never knew I knew all the words for the cussings I gave those heathen before our fellas found me! And Haney and the Chief will drive me crazy if I can't slap 'em down! Powder metallurgy does the trick, from what you told me. That's okay, then."

He stood up and stalked toward the front of the plane. Joe roused himself with an effort. He turned to look about him. Haney lay slumped in a reclining chair, on the other side of the plane cabin. His eyes were closed. The Chief lay limply in another chair. He smiled faintly at Joe, but he didn't try to talk. He was too tired. The return to normal gravity bothered him, as it did Joe.

Joe looked out the window. In neat, geometric spacing on either side of the transport there were fighter jets. There was another flight above and farther away. Joe saw, suddenly, a peeling-off of planes from the farther formation. They dived down through the clouds. He never knew what they went to look for or what they found. He went groggily back to his bunk in a strange and embarrassing weakness.

He woke when the plane landed. He didn't know where it might be. It was, he knew, an island. He could see the wide, sun-baked white of the runways. He could see sea-birds in clouds over at the edge. The plane trundled and lurched slowly to a stop. A service-truck came growling up, and somebody led cables from it up into the engines. Somebody watched dials, and waved a hand.

There was silence. There was stillness. Joe heard voices and footsteps. Presently he heard the dull booming of surf.

The plane seemed to wait for a very long time. Then there was a faint, faint distant whine of jets, and a plane came from the east. It was first a dot and then a vague shape, and then an infinitely graceful dark object which swooped down and landed at the other end of the strip. It came taxiing up alongside the transport ship and stopped.

An officer in uniform climbed out, waved his hand, and walked over to the transport. He climbed up the ladder and the pilot and co-pilot followed him. They took their places. The door closed. One by one, the jets chugged, then roared to life.

The officer talked to the pilot and co-pilot for a moment. He came down the aisle toward Joe. Mike the midget regarded him suspiciously.

The plane stirred. The newly arrived officer said pleasantly, "The Navy Department's sent me out here, Kenmore, to be briefed on what you know and to do a little briefing in turn."

The transport plane turned clumsily and began to taxi down the runway. It jolted and bumped over the tarmac, then lifted, and Joe saw that the island was nearly all airfield. There were a few small buildings and distance-dwarfed hangars. Beyond the field proper there was a ring of white surf. That was all. The rest was ocean.

"I haven't much briefing to do," admitted Joe.

Then he looked at the briefcase the other man opened. It had sheets and sheets of paper in it—hundreds, it seemed. They were filled with questions. He'd be called on to find answers for most of them, and to admit he didn't know the answers to the rest. When he was through with this questioning, every possible useful fact he knew would be on file for future use. And now he wrily recognized that this was part payment for the efficiency and speed with which the Navy had trailed them on their landing, and for the use of a transport plane to take them back to the United States.

"I'll try to answer what I can," he said cautiously. "But what're you to brief me about?"

"That you're not back on Earth yet," said the officer curtly, pulling out the first sheaf of questions. "Officially you haven't even started back. Ostensibly you're still on the Platform."

Joe blinked at him.

"If your return were known," continued the lieutenant, "the public would want to make heroes of you. First space travelers, and so on. They'd want you on television—all of you—telling about your adventures and your return. Inevitably, what happened to your ship would leak out. And if the public knew you'd been waylaid and shot down there'd be demands that the government take violent action to avenge the attack. It'd be something like the tumult over the sinking of the Maine, or the Lusitania—or even Pearl Harbor. It's much better for your return to be a secret for now."

Joe said wrily: "I don't think any of us want to be ridden around to have ticker-tape dumped on us. That part's all right. I'm sure the others will agree."

"Good! One more difficulty. We had two space ships. Now we have none. Our most likely enemies haven't only been building rockets, they've got a space fleet coming along. Intelligence just found out they're nearly ready for trial trips. They've been yelling to high heaven that we were building a space fleet to conquer the world. We weren't. They were. And it looks very much as if they may have beaten us."

The lieutenant got out the dreary mass of papers, intended to call for every conscious or unconscious observation Joe might have made in space. It was the equivalent of the interviews extracted from fliers after a bombing raid, and it was necessary, but Joe was very tired.

Wearily, he said, "Start your questions. I'll try to answer them."

They arrived in Bootstrap some forty-six hours after the crashing of their ship. Joe, at least, had slept nearly thirty of those hours. So while he was still wobbly on his feet and would be for days to come, his disposition was vastly improved.

There was nobody waiting on the airfield by the town of Bootstrap, but as they landed a black car came smoothly out and stopped close by the transport. Joe got down and climbed into it. Sally Holt was inside. She took both his hands and cried, and he was horribly embarrassed when the Chief came blundering into the car after him. But the Chief growled, "If he didn't kiss you, Sally, I'm going to kick his pants for him."

"He—he did," said Sally, gulping. "And I'm glad you're back, Chief. And Haney. And Mike."

Mike grinned as he climbed in the back too. Haney crowded in after him. They filled the rear of the car entirely. It started off swiftly across the field, swerving to the roadway that led to the highway out of Bootstrap to the Shed. It sped out that long white concrete ribbon, and the desert was abruptly all around them. Far ahead, the great round half-dome of the Shed looked like a cherry-pit on the horizon.

"It's good to be back!" said the Chief warmly. "I feel like I weigh a ton, but it's good to be back! Mike's the only one who was happier out yonder. He figures he belongs there. I got a story to tell you, Sally——"

"Chief!" said Mike fiercely. "Shut up!"

"Won't," said the Chief amiably. "Sally, this guy Mike——"

Mike went pale. "You're too big to kill," he said bitterly, "but I'll try it!"

The Chief grunted at him. "Quit being modest. Sally——"

Mike flung himself at the Chief, literally snarling. His small fist hit the Chief's face—and Mike was small but he was not puny. The "crack" of the impact was loud in the car. Haney grabbed. There was a moment's frenzied struggling. Then Mike was helplessly wrapped in Haney's arms, incoherent with fury and shame.

"Crazy fool!" grunted the Chief, feeling his jaw. "What's the matter with you? Don't you feel good?"

He was angry, but he was more concerned. Mike was white and raging.

"You tell that," he panted shrilly, "and so help me——"

"What's got into you?" demanded Haney anxiously. "I'd be bragging, I would, if I'd got a brainstorm like you did! That guy Sanford woulda wiped us all out——"

The Chief said angrily, between unease and puzzlement:

"I never knew you to go off your nut like this before! What's got into you, anyway?"

Mike gulped suddenly. Haney still held him firmly, but both Haney and the Chief were looking at him with worried eyes. And Mike said desperately: "You were going to tell Sally——"

The Chief snorted.

"Huh! You fool little runt! No! I was going to tell her about you opening up that airlock when Sanford locked us out! Sure I kidded you about what you're talking about! Sure! I'm going to do it again! But that's amongst us! I don't tell that outside!"

Haney made an inarticulate exclamation. He understood, and he was relieved. But he looked disgusted. He released Mike abruptly, rumbling to himself. He stared out the window. And Mike stood upright, an absurd small figure. His face worked a little.

"Okay," said Mike, with a little difficulty. "I was dumb. Only, Chief, you owe me a sock on the jaw when you feel like it. I'll take it."

He swallowed. Sally was watching wide-eyed.

"Sally," said Mike bitterly, "I'm a bigger fool than I look. I thought the Chief was going to tell you what happened when I landed. I—I floated down in a village over there in India, and those crazy savages'd never seen a parachute, and they began to yell and make gestures, and first thing I knew they had a sort of litter and were piling me in it, and throwing flowers all over me, and there was a procession——"

Sally listened blankly. Mike told the tale of his shame with the very quintessence of bitter resentment. When he got to his installation in a red-painted mud temple, and the reverent and forcible removal of his clothes so he could be greased with butter, Sally's lips began to twitch. At the picture of Mike in a red loincloth, squirming furiously while brown-skinned admirers zestfully sang his praises, howling his rage while they celebrated some sort of pious festival in honor of his arrival, Sally broke down and laughed helplessly.

Mike stared at her, aghast. He felt that he'd hated the Chief when he thought the Chief was going to tell the tale on him as a joke. He'd told it on himself as a penance, in the place of the blow he'd given the Chief and which the Chief wouldn't return. To Mike it was still tragedy. It was still an outrage to his dignity. But Sally was laughing. She rocked back and forth next to Joe, helpless with mirth.

"Oh, Mike!" she gasped. "It's beautiful! They must have been saying such lovely, respectful things, while you were calling them names and wanting to kill them! They'd have been bragging to each other about how you were—visiting them because they'd been such good people, and—this was the reward of well-spent lives, and you—you——"

She leaned against Joe and shook. The car went on. The Chief chuckled. Haney grinned. Joe watched Mike as this new aspect of his disgrace got into his consciousness. It hadn't occurred to Mike, before, that anybody but himself had been ridiculous. It hadn't occurred to him, until he lost his temper, that Haney and the Chief would ride him mercilessly among themselves, but would not dream of letting anybody outside the gang do so.

Presently Mike managed to grin a little. It was a twisty grin, and not altogether mirthful.

"Yeah," he said wrily. "I see it. They were crazy too. I should've had more sense than to get mad." Then his grin grew a trifle twistier. "I didn't tell you that the thing that made me maddest was when they wanted to put earrings on me. I grabbed a club then and—uh—persuaded them I didn't like the idea."

Sally chortled. The picture of the small, truculent Mike in frenzied revolt with a club against the idea of being decked with jewelry.... Mike turned to the two big men and shoved at them imperiously.

"Move over!" he growled. "If you two big lummoxes had dropped in on those crazy goofs instead of me, they'd've thought you were elephants and set you to work hauling logs!"

He squirmed to a seat between them. He still looked ashamed, but it was shame of a different sort. Now he looked as if he wished he hadn't mistrusted his friends for even a moment. And he included Sally.

"Anyhow," he said suddenly in a different tone, "maybe it did do some good for me to get all worked up! I got kind of frantic. I figured somebody'd made a fool of me, and I was going to put something over on you."

"Mike!" said Sally reproachfully.

"Not like you think, Sally," said Mike, grinning a little. "I made up my mind to beat these lummoxes at their own game. I asked Joe about my brainstorm in the plane. He didn't know what I was driving at, but he said what I hoped was so. So I'm telling you—and," he added fiercely, "if it's any good everybody gets credit for it, because all of us four—even two big apes who try kidding—are responsible for it!"

He glared at them. Joe asked. "What is it, Mike?"

"I think," said Mike, "I think I've got a trick to make space ships quicker than anybody ever dreamed of. Joe says you can make a weld with powder metallurgy. And I think we can use that trick to make one-piece ships—lighter and stronger and tighter—and fast enough to make your head swim! And you guys are in on it!"

The black car braked by the entrance to the Security offices outside the Shed. It looked completely deserted. There was only a skeleton force here since the Platform had been launched three months before. There was almost nobody to be seen, but Mike pressed his lips pugnaciously together as they got out of the car and went inside.

The four of them, with Sally, went along the empty corridors to the major's office. He was waiting for them. He shook hands all around. But it was not possible for Major Holt to give an impression of cordiality.

"I'm very glad to see all of you back," he said curtly. "It didn't look like you'd make it. Joe, you will be able to reach your father by long-distance telephone as soon as you finish here. I—ah—thought it would not be indiscreet to tell him you had landed safely, though I did ask him to keep the fact to himself."

"Thank you, sir," said Joe.

"You answered most of the questions you needed to answer on the plane," added the major, grimly, "and now you may want to ask some. You know there is no ship for you. You know that the enemies of the Platform copied our rocket fuel. You know they've made rockets with it. You've met them! And Intelligence says they're building a fleet of space ships—not for space exploration, but simply to smash the Platform and get set for an ultimatum to the United States to backwater or be bombarded from space."

Mike said crisply: "How long before they can do it?"

Major Holt turned uncordial eyes upon him. "It's anybody's guess. Why?"

"We've been working something out," said Mike, firmly but in part untruthfully. He stood sturdily before the major's desk, which he barely topped. "The four of us have been working it out. Joe says they've done powder metallurgy welds, back at his father's plant. Joe and Haney and the Chief and me, we've been working out an idea."

Major Holt waited. His hands moved nervously on his desk. Joe looked at Mike. Haney and the Chief regarded him warily. The Chief cocked his head on one side.

"It'll take a minute to get it across," said Mike. "You have to think of concrete first. When you want to make a cubic yard of concrete, you take a cubic yard of gravel. Then you add some sand—just enough to fill in the cracks between the gravel. Then you put in some cement. It goes in the cracks between the grains of sand. A little bit of cement makes a lot of concrete. See?"

Major Holt frowned. But he knew these four. "I see, but I don't understand."

"You can weld metals together with powder-metallurgy powder at less than red heat. You can take steel filings for sand and steel turnings for gravel and powdered steel for cement—"

Joe jolted erect. He looked startledly at Haney and the Chief. And Haney's mouth was dropping open. A great, dreamy light seemed to be bursting upon him. The Chief regarded Mike with very bright eyes. And Mike sturdily, forcefully, coldly, made a sort of speech in his small and brittle voice.

Things could be made of solid steel, he said sharply, without rolling or milling or die-casting the metal, and without riveting or arc-welding the parts together. The trick was powder metallurgy. Very finely powdered metal, packed tightly and heated to a relatively low temperature—"sintered" is the word—becomes a solid mass. Even alloys can be made by mixing powdered metals. The process had been used only for small objects, but—there was the analogy to concrete. A very little powder could weld much metal, in the form of turnings and smaller bits. And the result would be solid steel!

Then Mike grew impassioned. There was a wooden mockup of a space ship in the Shed, he said. It was an absolutely accurate replica, in wood, of the ships that had been destroyed. But one could take castings of it, and use them for molds, and fill them with powder and filings and turnings, and heat them not even red-hot and there would be steel hulls in one piece. Solid steel hulls! Needing no riveting nor anything else—and one could do it fast! While the first hull was fitting out a second could be molded——

The Chief roared: "You fool little runt!" he bellowed. "Tryin' to give us credit for that! You got more sense than any of us! You worked that out in your own head——"

Haney rubbed his hands together. He said softly, "I like that! I do like that!"

Major Holt turned his eyes to Joe. "What's your opinion?"

"I think it's the sort of thing, sir, that a professional engineer would say was a good idea but not practical. He'd mean it would be a lot of trouble to get working. But I'd like to ask my father. They have done powder welding at the plant back home, sir."

Major Holt nodded. "Call your father. If it looks promising, I'll pull what wires I can."

Joe went out, with the others. Mike was sweating. All unconsciously, he twisted his hands one within the other. He had had many humiliations because he was small, but lately he had humiliated himself by not believing in his friends. Now he needed desperately to do something that would reflect credit on them as well as himself.

Joe made the phone call. As he closed the door of the booth, he heard the Chief kidding Mike blandly.

"Hey, Einstein," said the Chief. "How about putting that brain of yours to work on a faster-than-light drive?"

But then he began to struggle with the long distance operator. It took minutes to get the plant, and then it took time to get to the point, because his father insisted on asking anxiously how he was and if he was hurt in any way. Personal stuff. But Joe finally managed to explain that this call dealt with the desperate need to do something about a space fleet.

His father said grimly, "Yes. The situation doesn't look too good right now, Joe."

"Try this on for size, sir," said Joe. He outlined Mike's scheme. His father interrupted only to ask crisp questions about the mockup of the tender, already in existence though made of wood. Then he said, "Go on, son!"

Joe finished. He heard his father speaking to someone away from the phone. Questions and answers, and then orders. His father spoke to him direct.

"It looks promising, Joe," said his father. "Right here at the plant we've got the gang that can do it if anybody can. I'm getting a plane and coming out there, fast! Get Major Holt to clear things for me. This is no time for red tape! If he has trouble, I'll pull some wires myself!"