"You're off duty," Martine said. "Relax."

  "I'll try, sir."

  "We've done a hard job," Martine said with satisfaction. "Six months in the field. Shoddy equipment. Only three of us to do everything. It's been quite a responsibility. If anything had gone wrong—" He took another drink. "Well, the ore's loaded, the records went off to Earth half an hour ago and everything's done. Every microscopic, piddling, vital detail. Tomorrow we go on duty again. But our mission's accomplished."

  "For all the good it will do in the long run," Dyson said, and told himself to shut up. He looked down warily at the glass in his hand, surprised to find it empty. Careful, Johnny, careful, he thought.

  "What do you mean?"

  "Oh, I don't know. After all, the nuclear physics boys have been working on the problem a long time without getting anywhere, haven't they? I don't see—"

  "Are you a qualified nuclear physicist?"

  "I came within an ace of being one," Dyson said.

  Martine stared at him. "What happened?" "Oh, I don't know." Dyson shrugged. "I guess I just realized finally how hopeless it all was. A good thing, too, from my viewpoint. If I were qualified now I'd be back home working on military projects like all the other competent boys. Whether they want to or not. It's practically martial law back there now."

  "Got to be," Martine said, looking at him curiously. "You can't just give up, you know."

  It was the same thing White had said, and it infuriated Dyson. They wouldn't see! He caught his breath for a sharp rebuttal, but what good would that do? None so blind, he thought, and remarked instead: "People don't change, sir. That's the trouble. People in general are—well, a bad lot, I'm afraid. They're bringing on the Blow-Up and no one can stop it. No matter what anybody does."

  "Very likely," Martine said, bored. "Have another drink."

  "Thanks, sir." Dyson leaned over and poured himself a second glass, wondering as he did so why he kept on calling the Chief sir ... For the first time, he realized, it didn't matter whether or not he irritated Martine. The important point was to allow time to get the fuel hidden. After that, Martine would stop being an officer automatically. (Of course, there was the revolver in the desk. He mustn't go too far.)

  "Where's White?" Martine asked. It was perfectly clear that he was bored. Maybe White would offer better entertainment.

  "He's—resting," Dyson said wildly.

  "Oh yes, energizing the robot for the take-off. I forgot. Well, now you've had your drink why don't you spell him? Maybe he'd like a drink, too."

  -

  DYSON KNEW he had to say something that would catch the Chief's interest—it didn't matter what—anything, anything. White must be left to do what he was doing until the job was accomplished. All doubt in his mind vanished as to whether White was actually operating the robot as he had promised. Dyson was suddenly confident about that. The only thing that mattered was to let him finish, to give him time, to keep Martine quiet.

  "Sir," he said, "sir, I'd like your opinion. You've had experience. If I'm wrong I wish you'd tell me. Is it wrong to feel my generation's been cheated of its rights?"

  Martine yawned. Then he leaned back to flip a switch, and a tape began to play Lili Marlene with infinitely saccharine emphasis.

  "You think the world owes you a living, eh?" he asked unpleasantly.

  "No, sir! Well—yes. Yes, a living, that's all. I want to stay alive. It isn't much to ask, is it? And the Blow-Up—"

  "Dyson, you've got atomophobia. Just try to remember that when we get back to Earth you'll have a better perspective. I know the last six months haven't been a picnic, but we had a job to do. Now—"

  "I've had perspective," Dyson said. "Ever since I was a kid. Sir, my father was Dr. Gerald Dyson."

  Martine opened his eyes.

  "Oh, So that's how you qualified for this trip. I wondered. You had the right technical training, of course, but—I wondered."

  "Oh yes, I had training. My father insisted on that. He worked on one of the first bombs, you know. He was one of the men who said, 'Oops, sorry.' Afterward he got a mission in life—to find an atomic control. Of course, there isn't any. He'd just lighted a stick of dynamite and handed it over to me. Until I was old enough to stand up for my rights and say the devil with it. Parents always try to compensate for their failures through their children. But I've finally got clear 'away from Earth. For the first time in my life I'm out from under the shadow of—" He paused, looked down at his glass, shuddered a little.

  "The shadow of the cloud, sir. A big black cloud, spreading out. I was brought up with it. My father ran the films over and over, studying them. I dreamed about that cloud. It got bigger and bigger. My father could have handed me an Eden on Earth, with controlled atomic power. It could have been like a magic wand. It could make all work unnecessary. By rights a fellow like me, born in the Atomic Age, should never have any problems at all. Unlimited power's the answer to everything. But the only answer we're getting is the Blow-Up."

  "I wish you'd quit saying that," Martine declared with sudden irritation. "You talk as if Earth had already gone up. It hasn't. Maybe it won't. There's a good chance we can still find a control. At least, we can go on trying."

  "But don't you see, that kind of thinking is just a pep talk to the galley slaves?"

  "If your precious Blow-Up ever does come," Martine said severely, "it'll come because people like you—" He paused and then shrugged. "Skip it," he said. "You've been under a strain, too. How about spelling White now at the robot and ... no, wait a minute. I forgot." He regarded Dyson with distrustful memory showing on his face.

  -

  DYSON THOUGHT of the robot climbing down the crevasse and Martine blowing his top. He almost grinned. The Chief's paramount nightmare must be that something would happen to the robot. It had taken seven years in building and it was as integral a part of the ship as the fuel load. The fuel made up the muscles, but the robot was the brain that kept the complicated organism of the ship functioning in space. Dyson had thought first of disabling the robot, but he'd discarded the idea very soon. For one thing, he didn't know how. The robot had compensatory protective devices, the equivalent of an ego balancing its id. And anyhow, later on it would be useful.

  When Eden was built on Mars the robot would furnish the perfect means of reducing details to a minimum. It could do almost anything. To Martine its primary function was running the ship, and it was less expendable than the men, but Martine's feeling toward the robot had a touch of narcissism, Dyson thought. Probably every time Martine looked in a mirror he saw a synthesis of Martine and robot.

  Later on, when the robot was made a hewer of wood and drawer of water—Dyson found himself suppressing a grin. Martine wouldn't like that at all. But he'd come around eventually. He could be bought, one way or another, just as Benjy White had been bought, with an intangible coinage.

  Martine sat up, lifted his feet to the floor and groped with his toes for the discarded shoes.

  "Guess I'll take White a little drink," he said.

  The whiskey's spreading warmth had been relaxing all the tension in Dyson's body. Now suddenly every nerve twanged taut again and he heard without a sound the same vibrating chords like distant music which he had sensed in his skull when he wore the control helmet. Only this time the music was all discords. He had to stop Martine. He had to.

  But Martine was on his feet now, stamping into his shoes, leaning to snap their catches. He tucked the bottle under his arm and picked up two clean glasses.

  "Sir!"

  "Well?"

  "I—I'll take over, sir. I know how to handle the transmitter. Let me go. I'll send White in—"

  Martine was at the door now. He simply shook his head briskly and went out, letting the door slam behind him.

  Dyson looked at the clock, horrified to see how little time had passed, horrified to realize that in spite of all he had done this could still be happening. Surely, he had thought, at the last moment something would occur to him, some clever way to outwit Martine, some way to carry through the scheme that had so far worked so smoothly ...

  Martine's footsteps receded down the passage into silence. Lili Marlene crooned itself away in over-sweet harmonies toward a close while Dyson swung like a metronome toward the door and away from it, waiting in vain for some idea about what to do next. Finally Lili Marlene was left for good and all under the lamplight, and Dyson discovered that he was opening Martine's desk with shaking hands.

  But the revolver wasn't there any more.

  So Martine would catch White while the robot was still at work hiding the fuel, and the ship would go back to Earth, and all Johnny Dyson's brave plans for a new world began to waver around the edges. Of course, he could run away, he could hide. They could go back without him, if they would—but in the long run he couldn't win. Sooner or later ships would come screaming down through the thin air above the scarlet plains, loaded with truant officers hunting Johnny Dyson ...

  -

  He stopped on the threshold of the storage room. Benjy White was solving nothing by twisting his hands together in an agonized way above the spindle-legged control carriage. The robot-cradle, of course, was empty. Martine wore the transmitter helmet, and by the look on his face Dyson knew the robot's activation directions were coming in clear and strong. Martine knew everything.

  His eyes met Dyson's.

  Dyson turned and ran.

  -

  A DOLL-SIZED JOHNNY DYSON ran across the contours of a doll-sized chart away from a doll-sized vinylite spaceship. He didn't dare look up because in the sky the face of a gigantic Johnny Dyson might be looking down at him. Time had slipped back fifteen minutes and he had fallen into the microcosm, and somewhere up there, enormous in an inconceivably vast spaceship, the whole scene was playing itself over again, from the moment Martine's voice had snapped an order-to-report into the inter-com.

  The vast, invisible finger of giant Johnny Dyson, fifteen-minutes-ago-Johnny-Dyson, had traced his trail in advance. He knew where to run. He knew the route the robot would have followed. But the time-factor was unknown.

  The fuel might already be stored in the cache and camouflaged. Even if it had, still he had failed. For White hadn't erased the robot's memory track and Martine could follow every step of the way through the path of the metal mind.

  Martine was running behind him now. So was White, he thought. But he didn't look back. He was running from more than Martine, more than men. He ran from the power and tyranny of a suicidal and homicidal Earth. Under his feet the ground rang hollow, as though his subterranean palace were already built, and waited, a hollow Eden, for its inheritor.

  Then on the hillside ahead he saw a flicker of moonlight on metal and in the grey pallor of the night the robot came ponderously into his range of vision, toiling mindlessly under its fuel load toward the cave.

  A shout sounded behind him, ringing thinly in the cold air. Glancing back, Dyson saw the dwarfed figures still running behind him. The ship looked doll-sized beyond. Illusion persisted. Everything had gone small. Ahead of the minimized White came marionette Martine, the transmitter gleaming on his head, while he guided a puppet's puppet, the control box, at a grotesque rocking run across the plain. All of them, pursuers and pursued, moved with the nightmare slowness and lightness that Martian gravity induces.

  Dyson's head start—for he had plunged headlong out of the ship, and the others had lost time searching for him in the corridors—was a totally useless thing. He knew it. But he could not yet give up the faint hope that somehow, somehow, a way would be revealed to him at the last crucial moment.

  There was a white flash in the dark, and the thin report of a revolver behind him. Probably it was a warning only, for he heard no whine of a bullet going by. He looked up, meeting the crooked gaze of the two moons like two uneven eyes—eyes in the face of giant Johnny Dyson. The sky around him was filled with conflict. Orion's club was lifted, Taurus' horns were lowered, Andromeda struggled in her chains, Sirius was a bared and gleaming fang. And bright among them hung a blue-green planet—blue for purity, green for peace ...

  Dyson's vision telescoped through a dizzy spiral, down diminishing vortices of time and space. At the end was the blue-green world and ten-years-ago Johnny Dyson, fifteen-years-ago Johnny Dyson, quite ignorant and quite safe. The world was his parents' responsibility in those golden days. Not his. Oh youth, youth, lovely and lost and safe.

  Martine fired again.

  Here-and-now Johnny Dyson ran on toward the robot, which was in the act of vanishing into the dark mouth of the cave. The cave was only an ant-burrow and the robot was a shining pale ant with a grain of sand clutched in its mandibles. Spatial dimensions had lost all importance along with the rest of the natural laws. Only in dreams did you seem to float like this when you leaped, running as if through glue from pursuing dangers.

  Directly ahead was a pile of shielded canisters, damper-hooks in place. Dyson slowed to study them, trying confusedly to estimate how many foot-pounds or tons of lifting pressure they represented. Not enough to lift the ship. There were only eight. If the robot had hidden all the rest, then Mars' apron-strings would still be strong enough to tie the ship down forever. If—if ... of course! If the rest were in the cave, and if he could get there first, then the answer was childishly easy. How could he have missed it? Exultation boiled up in him, filling his throat with triumph.

  He heard his name shouted, and he sprinted, bending low at each jump so the thrust of his toe would carry him forward and not up against the easy gravity of Mars.

  -

  HE REACHED THE CAVE MOUTH just as the robot's emerging thorax caught light from the rolling moons. It did not pause, but its false pupils examined him, the radioatomic brain analyzed him as a mobile obstacle, and the great worker-ant walked straight ahead. Dyson got out of the way. The worker-ant moved majestically downhill toward the remaining fuel-canisters.

  Dyson paused at the cave mouth, peering in. It was so dark in there. He hesitated for a moment, knowing the solution to his problem was waiting for him in the dark, but feeling a curious reluctance to enter that black enclosure.

  He glanced back. Martine and White were much closer, running silently, and the robot was moving down the slope toward them ahead of its twin shadows. There were more shadows than men moving toward him up the hill, twice as many shadows, in twinned pairs, one black and one gray on the purple mosses. Deimos and Phobos spun through the emptiness overhead, pale silver shaping the ghosts of all moving things behind them on the ground. But it was Phobos that guided them. Phobos, who is Fear.

  Dyson turned his back on them. They were still far enough away to look tiny. He could reach across the vinylite map and take the control box away from Martine between his thumb and finger ...

  Instead he took out a pocket fluorescent and shook it alight. With an uncomfortable feeling that he was somehow violating a sanctuary, he stepped into the cave. There were the canisters, row upon row against the rocky wall.

  This was the mouth of Eden. He had chosen this site for his underground palace, hidden safely away in case after all rescue ships did come from Earth. But he hadn't really expected rescue ships. The spreading cloud of his childhood had gradually swelled until Earth was scarcely visible to him any more. It was a shadow cast before the flash of the Blow-Up.

  Working quickly, with both hands, he stripped the damper-hooks from the canisters ...

  A few minutes afterward he ran out of the cave and down the slope toward the approaching men with their escort of nervous shadows. His shout broke on a high-pitched note of triumph.

  "Walk right in!" he cried across the plain. "It's all there, Martine! It's all in the cave! Go and get it!"

  Then the thunders began.

  -

  THERE WASN'T any real danger. Not as long as they stayed out of the cave. The fuel was blowing off canister by canister, not all at once, because each was a unit and constructed with every safety precaution mankind knew how to apply. Each one had a half-life of sixty-five seconds. They weren't blowing all at once because Dyson hadn't activated them all at once. He had only two hands.

  One canister blew. Eight seconds later another one blew. The power that should have lifted a spaceship was going into light and sound and radiation too subtle to look dangerous. A man could walk into the cave and right up to the canisters, if he wanted. And he could walk out again.

  What would happen to his cells, his marrow, his blood and bones, later, was another matter. Radium can be leached from the human body. But the invisible poisons in the cave couldn't be, ever. Gamma radiation leprosy, quite incurable, was pouring out of the canisters into the alternate white glare and blind darkness of the cave.