---

Mark Travers hoisted himself up from the floor. He leaned against the supply locker, rubbed his aching jaw where the big man's fist had just landed, and grinned ruefully.

The big spaceman didn't grin. He faced Mark straddle-legged and snapped, "Who are you?"

"Mark Travers." His smooth gray eyes surveyed the man's bulk. He thought he could handle him, but filed it for future reference when he saw the neutro-gun in the other's fist.

"Travers, eh. A blasted stowaway! You come aboard at Marsport?"

"Obviously."

"How?"

"It was easy," Mark shrugged. "Your ship was small, dark, and carried no insignia. I watched your men loading supplies secretly. Furthermore, you hadn't filed your destination with Central Bureau. Just the kind of set-up I wanted."

"You know a lot," the big spaceman's eyes went hard. "Are you a sneaking I-S-P? Never mind. I'll see for myself!" He came a step forward, and his gun got playful with the third button on Mark's plasticoid shirt. Expertly the man's fingers went over him.

"Careful, there, I'm ticklish!"

"So's the release on this trigger, so just stand still."

Mark stood still. The search revealed no papers or identification of any kind.

"I'm not I-S-P," Mark told him sincerely. "If I were, do you think you'd ever have lifted gravs from Marsport?"

"Okay, fella. I'm Mal Driscoll. Sorry I had to clip you so hard, but you never should have pointed that contraption at me when I stepped in here. So help me, I thought it was some new kind of weapon." His eyes narrowed. "What is it?"

For a mere second Mark hesitated. He glanced down at the small, stub-lensed box which he had clung to.

"Why, it's—only a camera. New type, invention of my own."

Driscoll nodded. "Come on, stowaway. We'll go up and see Janus. No skin off my teeth, if he wants to keep you aboard."

They stepped out of the room and along a corridor, bracing themselves against the forward thrust of the rocket engines.

"Who's Janus?"

"Our Commander."

"And what if he doesn't want me aboard?" Unobserved, Mark pressed a hidden stud in the black box. Tiny but powerful coils hummed to life, quickly ascended the scale to the inaudible. Camera? Mark smiled to himself and hoped none of the men here knew anything about cameras!

"You know the space-code on that," Driscoll answered his question. "If it is so desired, stowaways are tossed into space."

Mark racked his brain. "I don't remember that in the Interplanetary Code!"

Driscoll turned, grinned at him. "Who's talking about Interplanetary Code? We make our own!"

---

Janus was in a forward cabin poring over charts on a glass-topped table. Three other men were lounging there. Janus was six-feet-four, with bulk to match. He had flaming red hair and an outlandish full beard that made a vivid splash against the drab gray of his insulated tunic.

He scowled fiercely as the two men entered. Driscoll pushed Mark forward.

"Found this stowaway in the supply room. Says his name is Mark Travers. I don't think he's I-S-P, though."

Janus' deep-set gray eyes seemed to bore through Mark, then they flashed to the black box.

"What's that?"

"New-design projection camera. It—"

"Put it here," Janus indicated the corner of his desk. Mark did so with some reluctance. This man was no fool!

The other three men had come down off their bunks and stood there watching. One of them, Mark noticed, was a Martian.

"Now. Why are you here?"

"You seemed to be the sort of men I wanted to join up with."

"I said why?"

Mark wondered if this man would believe him. He didn't think so. Nevertheless, he'd already made up his story so he drew a long breath and told it:

"I was with Tri-Planet News Service working out of Chicago. I happened to uncover a huge spacer contract graft. I got the names of the higher ups, photostatic copies of incriminating documents—everything. But the men involved happened to be too high up; my story was squashed before it ever reached the wires. I would have been, too, permanently, but I escaped to Mars—"

Janus was laughing at him behind that red beard. Mark was sure of it. He shrugged and didn't attempt to go on with the fabrication. It had been a good try, anyway.

Janus said dryly: "Now tell me the real story. Or shall I tell you? You received one of the typical BINWI offers. You're running away to cool off, or maybe to keep your invention out of their hands. Is it this—ah—camera?" Janus glanced at the compact box lying there.

"That's right," Mark admitted, marvelling at this man. "They made me several offers but I wouldn't come through. The last one was 'typical', all right—backed up by some of their hired thugs."

"Why didn't you tell me this in the first place?"

"I wasn't sure how you felt about the BINWI." Mark was still wary.

"The same as you do, although I've never had any contact with them personally. My special peeve is the Tri-Planet Council, and the BINWI is a subsidiary. Bureau for the Investigation of New and Worthy Inventions. A laugh, ain't it?"

Mark didn't think so. "That bureau," he said, "is an octopus preying on the inventive genius of three planets! Their spies are everywhere, moving unseen, biding their time. You know the new anti-grav deflectors the Patrollers are using? A man named Anton Kramer worked that out. He had it near perfection when he suddenly disappeared. A month later the deflectors came on the market." Mark's voice was bitter. "There've been dozens of other cases. The BINWI usually gets what it wants, even if it means murder."

Janus nodded. "There's a man aboard who'll agree with you on that! Professor Brownell. Perhaps you shall meet him—later." He turned his gaze to the four crew members. "All right, men, how about Mark Travers? Do we accept him as one of us? A vote is in order."

"How do we know he's not a BINWI spy himself?" asked a small man with piercing black eyes. "He seems to know a lot about 'em!"

"I'm convinced he's not, Ferris. We covered Brownell's trail too well for that. Let's have the vote."

The "ayes" were unanimous and suddenly these men were friendly, smiling, as they stepped forward to shake Mark's hand. They were good handshakes, firm and calloused. Only Ferris' was reluctant.

"There's one thing more," Janus said quietly. "We'll need your picture for our—shall we say—rogue's gallery? I insist on that. Perhaps I can take it now—with your camera." He reached to the black box on his desk, lifted it carelessly up.

---

Mark found himself staring full into the stub-nosed lenses. Sudden sweat broke on his brow. His gaze lifted and met Janus' gray eyes, straight and steady upon him.

"Wait!"

"What? Not camera shy, are you?" Janus' fingers seemed to fumble, but his gaze never left Mark's face.

"The lens isn't set! It—it's special, you know." Mark stepped forward. His limbs seemed wooden. He took the box from Janus' hands, and pretending to adjust the lens, his thumb found the hidden stud and released it. The hum of the inner coils descended the scale again, became audible for a split second but only to Mark's ears; then they were dead.

He let out a slow breath, handed the box back. "Okay now. Shoot."

Janus waved it away. "Oh, well, it can wait. We'll get it later." He came around the desk, thrust out his hand. "Welcome aboard, Travers! You're one of us."

Mark suddenly knew that Janus knew his secret ... but somehow he wasn't worried. He wondered if any of the others had noticed the by-play; moreover, he wondered what being "one of them" meant....

He was soon to know. At that moment a voice sliced through the radio.

"Callisto calling! Earth-Station Six on Callisto! We have had you in our beam for the past twenty minutes. You are out of bounds and you display no insignia. As this is a violation of the Space-Code, you will go into a drift immediately and await the Patrollers who will escort you to Callisto for investigation! Refusal to obey constitutes outlawry against the Federation, and the Patrol will act accordingly!"

The men weren't startled. If anything they were amused. The one named Dethman simply straightened away from the radio and his hard, square face broke into a grin.

"Think of it, men, we're being outlawed! Now ain't that one for the books?"

The face of Ral Kaarj, the Martian, was blank and leathery. His heavy-lidded eyes blinked once or twice, but only his incongruously high-pitched voice revealed his emotions.

"Tri-Planet Federation!" he shrilled. "Out of bounds! By the red tails of all the Oogs on Venus, ain't anyone supposed to venture beyond the asteroids?"

"Not without sanction of those gray-beards in the Council," Janus said, "and the Earth Corporations who are the real power. You know how they try to squelch men like us, free-footers who won't play ball with 'em." He flicked open the communicator to Brownell in the control room. "How about it, Prof? Get that message?"

"Yes," Mark heard a voice reply. "All right, we'll go into a drift. Let the Patrollers come, we'll give 'em a show!"

"Right! Need any help?"

"No, but keep the communicator open. And take a look in the V-panel if you want." Brownell actually seemed pleased!

Janus clicked on the visipanel, turned the magnifying dials. Callisto was seen in the swimming blackness of space with the huge bulk of Jupiter as a backdrop. Under Janus' sure fingers the scene expanded, came nearer.

Minutes passed; then they saw six Patrollers speeding out to meet them. Brownell had cut rockets and they were in a drift now, waiting.

Waiting for what, Mark wondered. These Patrollers were speedy ships and deadly, equipped with atomo-bombs, dis-rays and magnetic beams! He shifted nervously.

The Patrollers came very near. Then they broke formation, arraying themselves three on each side of the outlaw ship. Magnetic beams, pale green and swirling, reached out to touch the hull. They fastened there tenaciously. In this manner they began the route back to Callisto.

Even Janus seemed a little worried now. He turned to the communicator.

"How about it, Professor? Those beams are powerful? Think you can slip out?"

"Wait and see; I promised a show, didn't I? Tell you what, though, better break out the acceleration harness!"

---

These were suits within suits, double layers of tough plasticoid. Mark stepped into his, opened the pressure valve that forced air between the two thicknesses. The outer one ballooned, giving a grotesque, roly-poly appearance. He bounced hard against the wall to test it.

"Better open them full," Janus advised.

They were ready. They stood against the far wall and watched the screen across the room. Callisto was looming. They'd soon be within its gravity.

Ferris, standing beside Mark, said in a low voice: "What kind of a news-man are you, Travers? Y'oughta be getting pictures of this. Make swell release stuff when you get back to Earth." His tone was mocking.

Mark felt a growing dislike of this man. He suppressed a retort, said curtly instead: "Too late now." He had placed his "camera" safely in an inside pocket.

The Patrollers' magnetic beams still towed them along at terrific speed, setting up a slight vibration in the walls.

Suddenly there was a new kind of vibration. Mark didn't know what it was. Certainly not rocket tubes.

"Get set!" Janus warned.

Someone muttered: "If he slips out of six magnetic beams—" but that was all. A fierce surge came beneath their feet, and Callisto seemed to leap at them. Within seconds a ghastly nausea gripped their insides. The ballooning suits were pressed so flat against the wall it became impossible to breathe! Their hearts pumped sluggishly, and a gray veil began to form before their eyes....

These were men so accustomed to hardships that space-acceleration meant nothing, but now they were experiencing something new in acceleration. They felt as if their entrails were being compressed into atoms!

Mark could barely see the screen now. The way Callisto was rushing at them he felt sure the planet was going to blank them out. He tried to shut his eyes, but even his eyelids wouldn't move! Then Callisto slipped off the screen, and Mark knew they must have made a sharp parabola. Two of the Patrollers were glimpsed far behind, reaching out futilely with dis-rays.

Even as he struggled for breath, Mark wanted to laugh; but the desire left him suddenly as the tremendous bulk of Jupiter loomed. If they escaped that gravity—

And they did. They came close, but their parabola tightened, then they were pulling away. Speed remained constant as Jupiter faded. Mark could breathe again but he ached through every inch of his body. He could only think wearily.

This, he thought—this meant they must have accelerated to the sixth, seventh or even eighth magnitude!

---

II

Phillias Brownell was a tough little character. He still breathed with difficulty as Janus unstrapped him from the pneumatic seat, and his face was ashen; but he hoisted himself up to his full stature of five feet five and his gray hair bristled. He went to work over the control console, jabbing hard at gleaming buttons and adjusting the complex set-up. By now Jupiter was fast fading in the darkness behind them.

"All right," he announced finally, "we're on robot control. We can rest easy for a while." He sneered in the direction of Jupiter. "We showed 'em some speed, eh? So they want my Frequency Tuner, do they? Let them come and get it! The dolts, the moronic interfering meddlers!"

Janus plainly showed his relief, as he winked at Mark, who said, "That was some chance you took. Suppose it hadn't worked?"

"But it did work! That was the final test, and it was necessary. I had to know how it would react against the beams."

Mark ventured a question. "Frequency Tuner? Is that what gave you the acceleration? I knew it wasn't rocket power!"

Brownell turned piercing black eyes upon him. "Eh? Janus, who is this?"

Janus vouched for Mark, explained his presence aboard. He added: "The Bureau's after an invention of his, too. A camera."

The Professor was startled. "Did you say a camera? Since when do they—"

"Ah, but Mark's is a very special camera." Janus smiled maddeningly, but in the next instant was clapping a friendly hand on Mark's shoulder. "Don't worry, Travers, your secret's safe with us. We don't ask questions. You've a right to know our destination, though; come on, I'll show you."

They repaired to the chart room, where Janus indicated a moving red line on a glass-encased chart of the solar system. Other lines were being traced, too, at various angles to their trajectory.

"The red line is our present trajectory. The others are the orbits of the planets. See, there's Jupiter behind us; notice how close we came."

Mark nodded. Already in his mind's eye he was extending their present parabola. Distances between these outer planets were vast beyond imagining! Saturn was just in sight, but at their present speed they would probably cross its orbit far in advance of the planet. Then came Uranus, and next Neptune. The space between Neptune and Pluto was vaster than all.

Mark felt just a little staggered. There was no known record of men having come this far! Not beyond Jupiter, in fact.

He turned to Janus. "How far do we go?"

"All the way."

"Pluto?"

"Beyond."

Mark thought that over. "There's no planet in our system beyond Pluto!"

"But there is. Planet X. An eccentricity in the orbit of Pluto indicates there must be a planet beyond. For years astronomers have known this, but no telescope has been able to pick it out."

Mark grinned weakly. "So that's where we're headed. I guess you know it'd be awfully easy to overshoot a mark like that!"

"Not with the Frequency Tuner. I understand very little of it, but the Professor assures me it's a directional finder as well as a power unit."

"Sure, sure. And assuming we locate Planet X and manage to land—what do you expect to find there?"

---

Janus' eyes were flecked with dancing lights. "What do we hope to find? George Ketrik! And if you know the man at all, you know that means adventure and riches."

Ketrik! Mark's mind went back. He began piecing together things he had heard, fragments and rumors. The man Ketrik and his amazing exploits had become almost a legend!

"But I have heard," Mark voiced slowly, "that Ketrik died! Plunged into the sun while trying to negotiate a landing on Vulcan."

"You don't really believe that? Sure, every few years you hear those stories, but Ketrik always shows up again." Janus sighed. "You know, I've almost come to believe that he's not human. Where other men go—men like us—they find that Ketrik has been there first. I've personally made two fortunes, and lost them, in following his trail!"

Mark was skeptical. "But even he wouldn't dare try for Planet X! He hasn't the speed that we have. It would take him—"

"Ketrik would dare anything! Why, six months ago I heard that he was planning this venture; that's why we're here. We five men pooled our savings to finance Brownell's Frequency Tuner and build this spacer, in secret, of course. Sure—it would take Ketrik maybe three months to reach Planet X in some dilapidated little rocket-powered craft. We'll make it in three days—but I'll wager he's already there!"

"With the whole populace kow-towing at his feet, most likely." It was Driscoll who spoke as he entered the room, followed by the other men. "Sure, I'll back the luck of Ketrik every time!"

Dethman shook his head. "Planet X is probably uninhabitable. But I'll bet my last pair of socks Ketrik's located a cave of diamonds, or maybe a platinum vein. Toss him in a Venusian sink-hole, he'd come up wreathed in swamp pearls!"

"He's that sort," Janus agreed. "It was platinum on Mars, cinnabar on Mercury, plumes on Venus. By the way, I got in on the plumes—made a fortune. And the other time I saw Ketrik—"

"I recall the time he showed up at the Venusian Prison Swamp," Driscoll put in. "One day he wasn't there, the next day he was—just like that. Inside a week he had organized a group of us for a getaway attempt. Hundreds of others had tried it and failed. Well, he led us safely across two hundred miles of swamp, supposed to be impassable. Know what was on the other side? A spaceship, all waiting and ready. He just wanted to prove it could be done, I guess."

"I only saw him once," Kaarj shrilled eagerly. "That was on Deimos. He had discovered the secret shrine of the Deimian ancients. He came out of that shrine decked from head to foot with blazing jewels—but the Deimians were waiting for him. They're a blood-thirsty tribe, and they were plenty angry...."

"I never heard this story before," Janus said. "What happened?"

"I stayed a safe distance away in my spaceship, watching and this is what happened. Ketrik made them a speech! I swear it! He climbed up on a block of stone in full range of their weapons—and do you know what his speech consisted of? The entire first chapter of the 'Advanced Principles of Space Navigation'. He quoted it most violently. Those Deimians didn't understand a word of it, but I swear to you, when Ketrik had finished they weren't angry any more! They cheered him! He walked calmly over to his space-cruiser and blasted away, jewels and all!"

"I came across him once on Mercury," Dethman contributed. "The barbarians from the dark side were warring on the race inhabiting the twilight strip. Well, if it hadn't been for Ketrik, the whole colony would've been wiped out. They almost made a superman out of him, wanted him to marry a thousand wives to make sure he'd leave plenty of his descendants there. And by Jupiter, he almost did! When I left he was still there, married to ten wives—or was it twelve?"

Mark was enjoying all this. He looked to Ferris, who seemed to be the only one without a story to tell. Ferris lit a venomous Venusian cigar, and sneered:

"I don't hold with all this hero-worship, and I don't believe more'n a tenth of it. Don't think we'll find Ketrik out here either. I've sunk a year's takin's from my placer on Mars into this venture—"

"And afraid you won't get it back, is that it?" Driscoll snapped. "Why, that placer you're yapping about was Ketrik's in the first place, and you know it! Sure, you'd rather hide out some place and manufacture more Frequency Tuners."

"We'll do that, too, once we make a strike," Janus said thoughtfully. "We'll equip a whole fleet with 'em, and really exploit the outer planets. That should give that addle-brained Earth Council something to really think about!"

---

On the third day they crossed the orbit of Pluto. Mark was in the control room with Janus and the Professor. The latter pointed to a thin thread of liquid helium in the directional-finder, surging slightly off center.

"Pluto's the nearest body now. It must be heavy, to drag us that way." He gave a touch to the Tuner's impellator, and the helium line came back to center as their acceleration increased.

The Sun had long since been a pin-point of light. The darkness ahead was no different from the darkness behind, but the men felt infinitely more alone. Behind were the known planets. Ahead was X—the unknown. It might be days more, or merely hours. No one slept now.

It was only hours later when the Finder began acting erratically again. Brownell, who seemed indefatigable, took over the controls from Janus. But he didn't try to adjust direction now.

"It's Planet X," he said. "Has to be! We'll let the Finder take us right there!" He switched on the visipanel and adjusted the lens to fullest power.

"It must be a dark planet," Mark pointed out. "Certainly the Sun's light doesn't reach it. How do you hope to see it in the panel?"

"Ordinarily I'd say you were right," Brownell nodded. "But look! There it is!"

Barely discernible on the screen, they saw a vague pin-point of light. Brownell glanced at the proximity indicator and gasped.

"Over three million miles—it can't be! Not the way it's pulling us now. Unless," he added thoughtfully, "it has a gravity grab equal to that of Jupiter at half the distance! Good Lord!" He tested instruments, gave experimental side thrusts with the Tuner, but they came back irresistably into the pull of the planet ahead.

Hour after hour they came nearer. The planet resolved into a dark disc with a peculiar surrounding halo.

"I don't like it," Janus reflected the thoughts of them all. "That light—where does it come from? Not the Sun! The Sun doesn't even touch Pluto!"

"Maybe it has a Sun of its own," ventured Kaarj. "On the other side."

"If it does, the sun moves right along with it in it's orbit!"

"You can tell from here that the planet has no axial rotation," Brownell announced. He looked a little worried. "This gravity drag is getting worse. We're accelerating. Better get into your harness." He set the example, and the men followed. "I think I can control it with the Tuner in reverse, but it pays to be safe. You never can tell, out here; these are strange conditions."

The planet was looming fast. The Professor's hand on the deceleration lever revealed the strain he was under. Below them now they glimpsed vast dark plains, and as they came nearer, huge stretches of forest. Mountains loomed. Far ahead was faint light, a few miles of "twilight strip" much as that on the planet Mercury.

The Professor was heading for this strip but Mark didn't think they'd make it. They were losing altitude with sickening speed. Mark had a final vision of the little Professor tugging desperately on the deceleration lever, of huge greenish-gray plants coming up beneath them.

Then a rending crash, a confusion of flying legs and arms. Just before Mark blanked out he knew their ship was still ploughing forward.

---

III

He came back to consciousness with a feeling of intolerable weight pressing him down. It was his own weight, he discovered as he tried lifting his head to look around. It was a terrific strain and he let his head fall back.

None of the men were seriously injured. The bulging harness had saved them. They called out to each other, but couldn't move except to roll their heads from side to side.

"Professor, did you say a gravity equal to that of Jupiter?" Dethman called out.

"That, or more. And yet this planet has a diameter of scarcely a few hundred miles! Strange!"

"Strange, he says," came from Driscoll. "What do we do now, just lay here for the rest of our lives?"

"Let's see you do anything else," Kaarj said drolly.

"Not me," Janus spoke. "You think I'll let this pee-wee world get me down? If I can only get to that Tuner control."

"I'm afraid this is one kind of gravity it won't counteract," Brownell admitted ruefully. "This world must be condensed as tightly as a white dwarf star! A cubic inch of matter weighing hundreds of pounds!"

Mark twisted his head around, saw Janus' huge frame struggling to move. He was a powerfully-built man, he'd be the one to do it if anyone did. Slowly, minutes at a time, he managed to drag one leg under him and then the other. He brought his hands into position. Sweat broke on his brow as he rolled himself over on all fours. Then with a terrific effort he hoisted himself erect!

He stood there, a straddle-legged, red-bearded giant. But only for a second. His legs buckled. He managed to hurl himself toward the starboard port, as he slid downward.

"At least I can see out now," he gasped. "We just did reach the twilight strip. There's a whole forest of great big green things, thirty feet high. Sort of like cactus, flat and spiny."

"They must have helped break our fall!"

"You said it! I can see a strip for over a mile, where we mowed 'em down. Hey! Look! For the love of—" Janus' voice dwindled off in amazement.

"Damn it, man, how can we look? What is it? What's out there?"

"People! Dozens of 'em! They're coming out of the forest. Oh—oh, they've spotted us. But they're not coming over. They just stand there jabbering and pointing."

"People on this world," Brownell muttered his amazement. "What are they like, Janus? Describe them!"

"They look kind of savage to me. Squat and furry, but they stand erect. Their legs are thick and heavy like an elephant's."

"Yes, that would be natural on this world. The terrific gravity."

"Gravity doesn't seem to bother them," Janus went on. "Let's see, now. Yes, in all other ways they seem to be low-evolutionary humans, except ... good Lord!"

"Except what? Damn it, Janus, go on!"

"They have knobs!"

"What?"

"Knobs! Growing right out of their foreheads. And they're lit up—the knobs, I mean. Sort of a soft white light."

"Another logical development of nature," said the Professor. "They live on the dark side, so their bodies manufacture the necessary light. Are they armed?"

"They are. Just crude spears and clubs, though, so I guess we're safe enough in here. Oh, oh, here they come. I think they see me!"

Twisting his head around, Mark could barely see a corner of the window where Janus lay. In the twilight gray beyond he glimpsed the horde of barbarians rushing at the ship. It seemed fantastic that they could move in such gravity, fantastic that any creature could walk.

One of them hurled a spear with deadly accuracy. It struck the window and glanced away. Others crowded around, pounding at the glass with clubs, clamoring to get at Janus who lay just beyond.

"Professor," Janus said wryly, "this isn't very pleasant. Are you sure that glass will hold?"

"Don't worry. It will take more than their pounding to crack four inches of crystyte."

"Hope you're right." A moment later Janus exclaimed, "Hey, some of these babies have electric rifles! Good Lord, I see—one, two, three—at least half a dozen of 'em! Wait a minute, though—they're only using them as clubs. The metal parts are corroded. Why, those are the old-type electric rifles popular on Earth two hundred years ago!"

"You must be having delusions," came from Ferris.

"No, I'm not. I've seen that type of rifle in the museums. Now how do you suppose they got 'way out here?"

For a few minutes there was silence, broken only by a faint ringing sound as the clubs beat against the thick crystyte. Then Janus announced:

"Here come more of 'em out of the forest. They're bringing up the reserves. Hey, this might be serious! They have a new kind of weapon." He peered for a moment into the grayness. "It's a huge thing, seems to be a sort of combination catapult and cross-bow. I don't like the looks of it."

A minute later the first shot came. It struck the spaceship very close to the window. There was a muffled explosion, and a flashing blue flame.

"By all that's holy—explosives! Powerful stuff, too. These babies aren't as barbarian as they look!"

"We've got to get away from here some way." Brownell was really worried now. "Janus, do you think you could make it to the controls? Perhaps by dragging yourself—"

"I'm sure gonna try it! Wait a minute, though—they're not going to bother us any more. They're scared!"

"Scared of what?"

"Damned if I know. They're staring off to the right, jabbering and pointing. Hah! There they go, they're running away!"

Driscoll said, "What did you do, Janus, make a face at 'em? That red beard of yours is enough to scare anybody!"

"Something's coming." Janus was straining his neck now, his face flat against the glass. "I think I can make it out ... yes ... holy blazing comets! What kind of a world is this? Get away from there, you! Hey—cut that out!"

Janus' voice had risen to an excited pitch. "Get set, men—I think we're leaving here!" The ship gave a sudden lurch and Janus rolled backward. His head hit the floor hard—enough to stun him a little.

And now their ship was moving! Not upward. It seemed to be dragging forward over rough terrain. In this tremendous gravity, every slightest jolt bruised them horribly. They could only lie there and take it. After five minutes of this their muscles seemed pounded to a pulp, despite the inflated suits still encasing them.

Then as suddenly as it had begun, the movement stopped. There was ominous quiet.

Mark, on the brink of unconsciousness, thought he was dreaming when he saw Professor Brownell leap to his feet! Now the other men were stirring. They rose dazedly. Gravity was normal!

They crowded excitedly around the windows. Outside was bright daylight, no longer the twilight haze. The barbarian horde wasn't to be seen, nor was—that other. Whatever it was Janus had glimpsed.

Janus groaned a little and sat up, rubbing his head. They questioned him eagerly.

"Maybe I didn't see it," he muttered. "You wouldn't believe me anyway. Gravity's normal, so let's get out of here."

And when they pressed their questions, he only shook his head stubbornly.

Heedless of their aching muscles, they zipped out of the bulging suits. Mark's hand went instantly to an inside pocket near his heart, where he'd placed his secret flat box with the lenses. He was relieved to find that it, at least, was undamaged.

---

Janus was breaking out the weapons. He handed each of them an atomic rifle and neutro pistol. Brownell had taken a sample of the atmosphere and announced it was fit for them. They debarked onto a plain where lush yellow grass sprang waist high.

"Strange," Brownell was muttering. He stared back the way they had come. Only a few yards behind them was the twilight zone! It was sharply defined, gray and misty, reaching sheerly up. Yet they stood in bluish daylight which extended ahead of them to the sharp, downward curve of the horizon.

Brownell walked slowly back to the twilight zone, gingerly testing the gravity. He entered the zone—and fell flat to the ground! Janus leaped to him, dragged him back.

"Did you ever see such a thing?" Brownell exclaimed as he rose. "Not only is there a sharp division of light and dark, but half the planet is terrifically heavy while the other half is normal. It defies all laws as we have known them."

Janus was peering intently into that grayness—toward the edge of the forest a hundred yards away. Suddenly he gripped the Professor's arm. His voice came a little hysterically.

"I wasn't dreaming, then. I see it! There it is—the thing that grabbed our ship! Don't move, you men, because I swear—it's watching us!"

Gradually they made it out, as they stared in the direction of Janus' gaze. It was a huge bulking shape that towered above the tallest trees. A roughly round, metallic body that rested on four jointed metal legs. Metal arms, too, dangled at its side.

"A robot!" came in a whisper from Dethman's lips. "A metal robot, but good Lord—look at the size of it!"

They were looking. Fifty feet above the ground they could make out its head, semi-spherical—and there were two eyes glowing with a greenish light, eyes that must have been large as dinner plates! It stood quite motionless in the gloom near the forest, watching them.

"That's the thing that towed us here?" Brownell whispered.

"Yes! I just got a bare glimpse of it."

"Must be friendly, then. But I wouldn't want to shake hands with it! The thing does seem to be watching us, doesn't it?"

"I'll fix it!" Ferris suddenly brought his rifle up, took aim at the glowing eyes.

Janus whirled, knocked the rifle aside. "You fool! That's an intelligent entity, I tell you! Want to get us killed?"

As though it had seen and comprehended the action, the robot's eyes blinked once or twice. It was eerie. Then it raised one of its arms and seemed to gesture—not at them, but beyond them. With that, it turned and stalked away, crashing through the forest.

"I get it," Mark said thoughtfully. "It was warning us to stay on our side of the fence!"

"And that's just what we will do. It's the only place where we can stand up, much less move about."

They walked back to the prow of the ship. "Where does this daylight come from?" Brownell was still puzzled. "There's no sun. Seems to me this gravity has something to do with it, too. Say! Do you suppose this light—"

He never finished, for at that moment they heard a shout ahead of them, and saw a group of men approaching. They were tall and straight, clean shaven, and dressed in trousers and tunics of rough texture but undoubtedly of Earth pattern—the pattern which had been popular hundreds of years ago! They carried weapons too, the old-type electric rifles which were so devastating at close range but not very effective at longer distances.

They came warily at first, but smiled when they saw the newcomers were not going to cause trouble.

"Greetings!" their leader said in perfect English. "You're from Earth? We thought we saw your ship crash, and came over to investigate."

Janus stepped forward and introduced himself, shook hands.

"My name is Donli," the other said. He pronounced it that way, crisply, running the syllables together. Mark suddenly wondered if this could be a contraction of "Donnolly".

---

Donli and his men were speechless for a moment, staring in turn at the spaceship, the new-type weapons, and Ral Kaarj.

"You have never seen a Martian before?" Kaarj grinned at them in a friendly manner.

"Pardon our staring," Donli replied. "We have never seen a Martian, nor such a spaceship as this, nor any other world. We have waited long for this! Long!"

"You've seen no other world. But you are Earthmen."

"We have been here always."

"I begin to understand," Brownell said. "There are others of you here? Where do you stay?"

"Our city is only fifty miles from here. We shall be happy if you accompany us there. We have good roads, and surface cars. Our leader, Mari, will explain everything to you." Donli paused, glancing nervously into the twilight strip. "You should be of great help to us against the Perlacs, with your new weapons."

"Perlacs? Are those the furry creatures with the lights on their heads?"

"Yes. We call them that because Perlac is the name they give to the world. They have warred on us for generations. We number a mere five hundred, and they are thousands." Donli looked worried. "And now that the robots are active again, we are in even more danger."

"We saw one of those metal giants," Janus exclaimed, "just a few minutes ago!"

"Yes, we saw it too. We came up just as it was stalking away. It's the first we've ever seen, but we have heard much about them; the stories have been handed down. There is supposed to be a great temple on the dark side, where the robots are housed."

"More of them?" Mark exclaimed. "I hope they stay over there, then!"

Donli shook his head. "This I know: if the robots are roaming again, as they did many years ago, none of us will be safe."

"Then let us go to your city," Brownell put in. "We should be able to lift gravs now, if the Tuner hasn't been damaged."

It hadn't been. In a few minutes they were winging low across the plains to the horizon.

The city bore the unusual name of "Frell", and lay semi-circularly at the foot of a sharply rising hill. People were seen, men and women alike, working in the surrounding fields.

Donli led them through the main street. The buildings were of a dark substance that might have been earth compressed to concrete hardness. They entered the most imposing of these buildings, and thence to a huge room which was almost the size of a theater on Earth.

"Make yourselves at ease," Donli said, "while I summon Mari. She will probably be at the laboratories now."

"Mari," Driscoll said, when Donli had gone. "So their leader is a woman! And they have laboratories!"

They gazed about them. The curious daylight came through windows of glass or similar material. There were chairs and tables of finely-wrought metal. Along one wall were bookcases filled with charts and uniquely-bound volumes. There were other volumes too, which seemed vaguely familiar.

Brownell walked over there.

"Look at this! A whole case full of books from Earth—scientific, technical books, all of them!" He read a few of the titles on the faded bindings. "These were all popular hundreds of years ago. And these others," he waved, "are probably the entire recorded history of these people. I'd give anything to look into them." He didn't touch the volumes, but remained thoughtful.

Mark too was thoughtful. "Frell," he mused. "A strange name for this city. Seems as though it ought to mean something, but I can't quite place it."

---

Donli returned soon, accompanied by Mari. She was tall, lithesome, her features classical and still beautiful despite smudges of sweat and grime from the laboratory. Her golden hair was braided into a halo which gave a queenly appearance, and her eyes were bluer than the strange daylight of this world. Skirt and tight-fitting bodice were of rough texture but dyed a rich golden color.

Involuntarily the men gasped, but Mari did not mind that or their stares. She seated herself and bade them be seated opposite her. Then she leaned forward, searching their faces. Not until then did they notice that her eyes were cold, suspicious.

"You have come from Earth, of course. And Donli tells me this strange one is Martian. Who is leader among you?"

"Why, I suppose I am," Janus said. "Either me or Professor Brownell, here."

"Professor?" Her mind seemed to grope for the meaning. "Ah! That word means a man of scientific learning, does it not?"

"In this case, yes," he answered.

Brownell spoke softly. "Madam, we come in peace. We want to be friends and we want to help you, if we may. You need have no suspicion of us."

"No suspicion? You come from the dark side! From the Perlacs!" She spat the last word venomously.

Donli, standing there, seemed troubled. He said:

"We only found them near the twilight zone. They were most friendly in manner and speech! They seem—"

Man waved a hand, and he was silent. She said:

"Men of Earth, you wonder why I am suspicious? Know, then, that we observed your ship five days ago, crossing our land with tremendous speed and heading for the dark side! Why have you waited until now to come here? It could be that you have allied yourselves with the Perlacs! Have they sent you here?"

There was a moment of stupefied silence. They could scarcely believe that she was serious, but her cold manner assured them of it. Then the answer must have dawned on all of them at once.

"Ketrik!" Janus boomed, hoisting his big frame from the chair. "By all that's holy, he did reach here! She must have seen Ketrik's ship!" Then he sobered. "But—if it was streaking for the dark side, it was surely out of control. Ketrik must be dead by now. To think I'd live to see the day when that man blanked out."

Mari had drawn a strange looking pistol from a belt at her waist. She gestured with it now and said:

"Be seated, please. We will talk yet a while. This Ketrik—he is another one from Earth?"

"Yes, he came before us. Came alone. We only landed here today, a few hours ago! Believe me, we want no part of those Perlacs. We had a little trouble with them."

She seemed relieved, and satisfied at last. "Forgive my suspicion of you. But where the safety of my people is concerned, I cannot be too careful. We have had trouble with the Perlacs, always. The greatest trouble is yet to come and it is brewing fast." She appeared to be marshalling her thoughts, then she went on:

"We are the seventh generation of a party of Earth people who arrived here hundreds of years ago. My direct ancestor, Wilm Frell, was leader of that expedition. Our city is named in his honor!"

"I've got it!" Mark exclaimed. "She means William Farrell! The Farrell expedition was one of the earliest and most ambitious interstellar attempts. Men had already reached the moon and were trying for Mars. Farrell set out with a hundred men and women aboard—"

"A hundred and forty," Mari corrected. "We have his log here. They missed Mars, their compasses were wrecked in the asteroids and they continued outward for months, finally crashing here. We still do not know what planet this is!"

"You're beyond Pluto!" Brownell told her. "But how could they have survived a crash on this heavy world?"

"It is one of the miracles. The records tell of it. They landed near the light! The light at that time encompassed a very small area, only a few miles. Gravity there was normal, but beyond, it was very heavy. They investigated the center of light and found the Stone."

---

Brownell was excited. "I suspected something like this! The Stone? What is it?"

"We still do not know, except that it supplies us with light and normal gravity and a temperate zone very favorable to our crops. It defies our science, and it certainly must have come from somewhere far beyond our solar system! Our ancestors found it deeply buried and dug it out. The moment they did—"

"Yes?"

"The light from it spread slowly, very slowly. In about ten years' time it had encompassed this entire hemisphere, stopped only by the sharp curvature of the planet."

"And as the light spread outward, the heavy gravity vanished?"

"That is true. We have the Stone now atop our hill, which is the highest spot. Our ancestors, however, had to fight for it time and again. The Perlacs at that time were really savages. They had known of the buried light but were afraid to approach it. Later they tried to get the Stone, but were always driven back into the darkness. They have warred on us ever since—for generations!

"In the last few years they have become very strong. They are using explosives now. I believe that ages ago, long before the first Earthmen came, a civilization existed and died here. The present Perlacs must have discovered remnants of an ancient science, and are slowly reviving it!"

There was a moment of silence. Janus took advantage of it to hand his atomic rifle to the girl, and his neutro-pistol as well.

"Have you ever seen weapons like these?"

She examined them excitedly, especially the neutro-pistol. "Donli, look at this!" she pointed at the firing coils. "It seems to be the same principle we're working on!"

"Do you mean to say you're trying to invent a neutro gun?" Janus was amazed.

"Yes," Donli answered. "We've been working on it for the past several years, but it's been slow and hard. Sometimes disastrous." He stepped to a bookcase, brought out one of the ancient volumes. It was Spurlin's Evolution and Control of the Free Electron.

"We've worked from the principles set forth here," Donli explained, "and with some slight measure of success. But we feel that we're treading on dangerous ground. Only a few months ago one of our laboratories was blown up and four men killed."

Brownell nodded. "Even when Spurlin wrote that book there was no real control of the electron. It came later. Anyway, we can help you now! We have the real models here to work from. Would you like to see these guns in operation?"

It was a needless question. They repaired outside, where Janus demonstrated the atomic rifle first, aiming at a harmless clump of bushes some fifty yards away. The atomic pellet struck and exploded, leaving a miniature crater.

"That," Brownell said, "is an example of uncontrolled atomic explosion. Rather crude, but it serves its purpose. Now let us observe a refinement of it. Controlled, electronic action."

Janus aimed the pistol. A bluish, pencil-thin ray leaped forth. Where it touched, substance vanished into a froth of flame. The ground itself became incandescent glass. The ray remained constant so long as his finger touched the firing stud.

Mari was excited. "Then you will help us perfect ours? The Perlacs are becoming stronger than we have ever known them, and whenever they start scouting the twilight zone, it means trouble. Donli tells me the robots are active again, too!"

"We can and will help you," Brownell assured her. "I doubt if those overgrown robots will stand up long under an electronic ray!"

The Professor was eager to see the Stone, and Mari graciously accompanied him to the crest of the hill where it was housed. The others, meanwhile, went with Donli on a tour of the shops and laboratories.

---

IV

Brownell told them later, in great excitement: "I swear to you, it defies all physical laws as we know them! It's merely a shiny chunk of rock, a few yards in diameter—but do you know, I believe it actually feeds upon gravity! I have always believed that gravity, magnetism, and other such universal forces are all a part of the electrical spectrum. Some peculiarity in the atomic structure of this Stone draws the straight-line force of gravity to it, and that force is then oscillated, transmitted into light! The process is unending!"

"That's all very well," Mark told him, "but I believe the greatest miracle is right here in the laboratories. These people have had to utilize the barest elements of this world, but they've done wonders. They have plastiglass, and farm implements, and electrical power—even crude atomic furnaces."

"They'd have their neutro-pistols right now," Janus agreed, "but they hit the same stumbling block that baffled our scientists for so long."

For days they worked ceaselessly on the neutro-pistols. Mark and the Professor together laid out the blueprints, devising a radical and more potent design for the firing coils. The latter was surprised at Mark's knowledge of electronic principles.

"I may surprise you even further, one of these days," Mark promised.

And now the urgency of their work was really impressed upon them. Scouts returning each day from the twilight zone reported that the Perlacs were gathering. Thousands of them swarmed the forests on the dark side, apparently massing for an all-out attack. There had been a few preliminary skirmishes but nothing serious as yet.

Donli undertook the task of setting up barricades at the twilight border. These were huge shields of light but durable metal, arranged in strategic positions, easily movable. And the work at the city went on apace.

Janus and the others directed work at the forges and metal shops. Everyone, men and women alike, who could be spared from the border defenses, were given assignments. Mari was a surprise to the new men. Already she knew the ancient science textbooks by heart, and she thirsted for more knowledge. She was everywhere, directing, helping, learning. She grasped the principle almost at once when Brownell explained:

"Briefly, the atom itself must not be shattered. That has been your mistake. Successive sheathes of electrons must be stripped without disruption of the ultimate atomic structure. That means swift transmutations, not disintegration. Most important of all, the electrons must be propelled along a controlled, directional beam."

Only Ferris was dissatisfied at the hard work. In their quarters, at the end of the first week, he complained:

"What's all this getting us? I thought we came out here to make a fortune! That's the story you gave me, Janus, when you rooked me into this deal."

Janus looked at him distastefully. "Haven't you ever wanted to do a decent act in your life? Lord knows I've done some scandalous things, but these people need our help now and they deserve it!"

"That's not getting back the fortune I sunk into this venture," Ferris grumbled.

"We'll think of that later."

The work was slower than they wished, for it became apparent the Perlac attack was going to materialize any day, any hour. As leader of the defense, the all-out call was left to Donli, who, with his select group, remained at the border constantly now.

And on the tenth day, even before the new pistols had been assembled or tested—the call came. One of the scouts raced into the city with the signal.

---

Everyone, men and women alike, left their work instantly. Dozens of the electrically-motored surface cars were waiting, and soon they were racing along the road. Within the hour they had reached the twilight zone to reinforce Donli's group.

Each person was equipped with an electric rifle which, at the longer distances, stunned but was not fatal. And there were quantities of atomic grenades. The new Earthmen retained their atomic rifles and neutro-pistols, as they better understood the operation of these weapons and could use them to more advantage.

The attack had not yet come but Donli was expecting it at any minute. Each group took up its assigned position behind a barrier. Mark found himself beside Janus and was glad, for he liked that blustering, red-bearded giant.

"It's going to be hell," Janus promised, peering into the twilight gloom. "We have to wait for them. The Perlacs can come over into our lighter gravity, but their gravity'd be fatal to us!"

Mark nodded. "It means we'll be fighting a strictly defensive battle."

The twilight beyond faded into the darkness of the huge forest, and not a Perlac was to be seen. Not so much as a moving shadow. But they were there, Mark knew, thousands of them; and when they came it would be silently.

And silently they came. Mark's first intimation was the explosion of grenades far down the line, and then he saw them—hordes of Perlacs, heavy of limb, but coming with amazing speed. Most of them were using cross-bows, and Mark realized that some of the shafts were equipped with metal-tipped explosives. Then he was too busy for further observation, as he brought his atomic rifle to bear.

The old style electrics were at work too, all along the line; and the grenades blasted huge gaps in the advancing tide. But still they came, moving now across the lighter zone. Thousands hadn't been an overstatement! The dark tide came rushing over their stunned and dead.

And now those explosive tipped shafts were having effect. Several of them struck a barricade next to Mark, and tore the metal from the foundations. Now Janus, beside him, was bringing the neutro-pistol into play.

Savagely Mark swung his beam in a never-ceasing arc, exulting at the swath it cut before him. Further down, Driscoll, Kaarj and the others were doing the same. Together with the grenades it seemed to stem the tide, but only for a moment.

"Keep it going! Keep it going!" Janus was yelling. "These beams are good for hours!"

The very silence of the attack made it the more terrible. No yells, no screams of fury came from the heavy-furred Perlacs as they littered the terrain by the score.

Then, as suddenly as they had come, they retreated. The seven sweeping beams had done the work well, but in an unexpected manner. Flames were leaping in the lush grass between the defenders and the forest!

"Respite!" Janus yelled. "Ten minutes, maybe. They'll be back when that grass is burned down!"

But there was no resting now. A score of men were dead and twice that many wounded, who had to be carried back from the battle line. Three of the barricades were wrecked, and they strove to get these into place again.

Mark noticed Mari, sweat-grimed and weary, her golden hair streaming down. But she was magnificent still, a tower of strength as she hurried along the line giving aid and encouragement to her people.

"I wonder where the robots are?" Mark suddenly remembered as he worked beside Janus. "If the Perlacs have learned to reactivate those monsters, as Donli thinks—"

"Encouraging, ain't you? As if we're not having a hard enough time as it is!"

And then Mark remembered something else. Remembered so suddenly that he began laughing, a little wildly, and Janus slipped him a light one on the jaw.

"Come out of it, lad! None of that, now—we're not licked yet!"

But Mark had reached to his inner pocket, and brought out his secret flat box. "Remember this, Janus? Good Lord, but I ought to be blasted for forgetting it! You always knew it wasn't a camera—well, now you're going to see it in action!"

"Good, lad! I hope you've got something there. Here they come again!"

---

This time the Perlacs had massed their forces, and they came in two wide flanking movements aimed at the ends of the barricades.

"Let them get close," Janus passed the word to the men, as they hurried down to the left. "Then give them your grenades—all you've got!"

Grim-faced they waited. Mark once more touched the release stud on his box, exulted as the coils hummed into power.

"Now!" Janus yelled at last, and swept his beam into play. Simultaneously the grenades rained outward. The terrain erupted in geysers of blackened grass and fleshy fragments. But determinedly the Perlacs came, and their cross-bow shafts filled the air.

Despair began to touch the Earthmen now. It was obvious the fanatical Perlacs were going to make this a war to extinction, and there could be but one final result. The Perlacs outnumbered them a hundred to one. If only they could have gotten the new electronic weapons ready in time! Even their grenades were running low now.

Grim-lipped, Mark waited for the next onrush. He passed his neutro to a neighbor and concentrated on his box. Its power had been proven in minor tests, but this would be the maximum!

The wave came. More of them now than before. Mark stepped for a moment into the open, heedless of the shafts. The box, held waist high, looked for all the world like a camera....

But the result was devastatingly different!

The men felt a violent holocaust of air around them, rushing away from all sides. For seconds they couldn't breathe or move! The temperature dropped so suddenly that they were literally frozen where they stood! Then warmer air came pressing in again but still they didn't move, because now they were staring—staring at the miracle.

In a hundred-yard area before their barricade the mass of Perlacs were motionless, many of them arrested in grotesque postures! Others had literally burst outward. But all were dead, and now they began to topple over, like frozen statutes!

Another wave was coming behind, just beyond the area. Now they wheeled and fled for the forest. Quickly Mark adjusted the sights and gave them another burst. The same thing happened. The rush of air, the sudden drop in temperature—and the horde was a mass of frozen corpses. But this time, the box became hot in Mark's hands, burning them severely, and he quickly dropped it.

At the other end of the line the defenders weren't doing so well. The Perlacs had gained that end of the barricade, and the battle was furious and to the death.

"Come on!" Mark raced for that end, followed by the others. But now Mark couldn't use his weapon, for it would mean blasting Earthmen and Perlacs alike!

And then, fantastically, the battle seemed to hang poised.

There came a grinding, shuddering sound. A series of these sounds. The ground seemed to vibrate, and then along the twilight strip came a towering, stalking, fifty-foot shape. One of the robots! It came swiftly, purposefully, huge eyes glaring down—straight for the battle line!

---

V

"This does it," Janus groaned. "That thing looks mad!" But no other robots came, and he raised his beam-pistol in readiness as the great monster came bearing down.

"Hold it," Mark caught his wrist. "Hold your fire, men!"

For the Perlacs were fleeing! Forgotten now was the fury of battle as they raced en masse back to the darkness of their forest!

And abruptly the robot swerved in its course, went after them with purposeful strides. It bent down a little and swept huge, claw-like hands close to the ground. A few of the Perlacs were caught, dashed to the ground, never to rise. Almost gleefully the metal monster trampled down the edges of the forest. The Earth people could only watch wearily, numbly. It was over. Unbelievably, the battle was over.

Tiring at last of its mad sport, the robot turned and came striding back. Heedless of Mark's warning, Mari stepped forth and faced it defiantly, rifle held in readiness. Tall and straight, her golden hair tumbling down, she was a defender of her people to the last.

And the robot paused! Only for a second, during which it seemed to be surveying her. Then it came on, but stopped some twenty yards away.

Then it spoke! The voice was rasping, metallic, but the words were unmistakable:

"Hi-ya, bud. What's cookin'?"

Janus' voice was a ridiculous gurgle in his throat. He took a step backward and his eyes bulged. For the thing had seemed to be addressing him!

At last he got the words out: "Ketrik! By all the red-tailed Zigs on Venus, it's Ketrik! Only he could use an archaic expression like that—what's cookin', indeed!"

There came a rumble of metallic laughter.

"Hi-ya, Janus! Haven't seen you in years. And Kaarj! Last time I saw you was on Deimos, when I robbed the temple of ancients. How are you, kid?" The robot went down, extended a long metal finger as big around as a man's arm. Kaarj retreated hastily!

"Well, ain't any of you glad to see me?" the voice came mockingly. "And after I saved your battle, too!"

"Sure, we're glad to see you," Janus replied shakily. "But good Lord, man, come down out of that thing so we can get a look at you!"

"Hell, no. I'm havin' fun! Anyway, I'm not up here. Not the real Ketrik. My body's lying in an alcove back there at the temple of robots."

Mari had come to stand beside Janus. Her face was flushed from the recent battle, but some of her defiance had fled. The robot bent closer still, seemed to be peering. Then came a long whistle, metallic but shrill, and one of the huge eyes winked!

The girl seemed to recognize that primitive sound and her face turned a deeper red. But she stepped a pace forward.

"Mister—ah—Ketrik, you have saved my people and have earned our undying thanks! But what about the Perlacs—do you think they'll be coming back again?"

The robot chuckled. "Not for a long time! Certainly not when they know I'm around. Those babies have given me a wide berth so far." He added: "I've been intending to pay a visit to your side of the world, but I could tell those dark-skinned brutes were up to something. I decided to hang around and await developments."

"But Ketrik"—Janus hesitated—"what's this about your body?"

"Don't worry, it's safe. This is only the mental part of me. Sure, there's a huge temple about ten miles back, with dozens more of these robots standing around idle." A sudden thought occurred. "Want to take a look? I could carry you across the heavy gravity."

"No thanks!" Janus declined. "My scientific interest doesn't go that far. Maybe the Professor, here—"

"Sure!" Brownell came forward, eager.

"I'll go too," Mark said. "I'd like to see how those robots work."

Ketrik extended a huge hand. Brownell and Mark clung tightly as it swung them up. With the two men perched on its shoulders, the robot went striding back through the forest.

The temple, massive and pillared, rested in a wide clearing.

They saw the robots, dozens of them lining the walls. The quartz discs of their eyes were now dull and lifeless. And near each robot, fifty feet high in the wall, were alcoves.

"Gravity here is normal!" Mark noticed suddenly.

"Yes," Ketrik replied. "That's probably what saved my life. I crashed right through the roof!"

They saw Ketrik's spacer on the floor below them, its nose and forward tubes crumpled beyond recognition.

"I'll show you my body." He strode to one of the alcoves, and the men stepped from his shoulders onto a stone ledge. Before them was a thick glass coffin. Resting in it was the material Ketrik!

---

It was a large body, as large as Janus, but clean shaven. The blue eyes were open and staring, and even in this suspended state there seemed to be a quality of recklessness, even amusement, about them.

"How do you get the mental self into the robot?" Brownell asked.

"Damned if I know how it works," there was almost a shrug in Ketrik's robot voice. "I just experimented with the thing."

He just experimented! Mark marvelled at this man.

"Don't touch it," Ketrik warned, "but you'll notice there are two cathodes attached to the temples of my earth body. See how the wires lead out, and up to that panelled board on the wall? There are all kinds of coils and things behind that board. Those other cathodes, that you see dangling, were attached to the brain plate of the robot. I suppose the molecules of your mental self flow through the wires. When the transference is complete, you merely detach the cathodes and start walking about, a full-fledged robot! I tell you it's wonderful!"

"Ketrik," Brownell said, as they went back through the forest, "we should be returning to Earth as soon as we complete the new weapon for Man's people. Don't you want to return with us?"

"No, I think I'll stay. I want to be sure those Perlacs don't cause any more trouble for a while."

"There wouldn't be any other reason?" Mark grinned.

"There would and is." The smile was in Ketrik's voice, if not on his metal lips. "I like that golden-haired Amazon—what's her name—Mari?"

"But why return at all?" Mari wanted to know, when the Professor announced the plans. "You have said you wanted a base for the manufacture of your Frequency Tuners. What better place than here?"

"Thank you, my dear. I had thought of that, but after all this is your world, and we are intruders."

Mari was hurt. "After all that you've done for us? And you can do so much more!"

"Then rest assured we'll be back, possibly within a month. True, there is much to be done here but we need new supplies, tools, equipment of every sort."

Janus said: "And with your permission, we'll want to bring back some new men. Not rogues and adventurers like me, but scientific men who can come here and work out their ideas without fear of that stupid Earth Bureau. Men like Mark, here, and the Professor."

Brownell nodded agreement. "I see a new regime. The Tri-Planet Council will have to cooperate with expanding endeavors, or take a back seat. Already I know two men on Earth, and four on Mars, who'll be delighted to come here to carry on their work. And Mark, that reminds me. That new weapon of yours. I think we can ask about it now?"

"Oh, it's nothing much, but I wasn't going to let the Bureau have it on their terms! It's merely an advanced frigidation idea. Works along an extended magnetic beam, absorbing all heat in a given area, almost to absolute zero."

"And he says it's nothing much!" came from Janus.

"It still needs some working out. The coils didn't stand up, the last time I applied it out there."

In two more days they were turning out the neutro weapons in quantity. During that time nothing more was seen of the Perlacs, as the robot-Ketrik maintained a vigilance. Brownell made a last check-up of the spaceship, and more important still, he strengthened the Frequency Tuner to counteract the gravity.

---

On the last night, Mark tossed restlessly in his bed. He could not sleep, and he didn't know why. Was it something they had forgotten? He didn't think so. Nevertheless he had a preternatural awareness of something wrong....

He arose, dressed quickly. There was never "night" on this side of the little world, but the rooms were automatically dimmed. Silently he tip-toed through the rooms. Brownell was there, sleeping peacefully. And Janus, and all the others.

No! Ferris was gone.

Mark's heart leaped. He had never liked that man, never quite trusted him. Now it came back. Ferris' eternal harping about the fortune he had put into this expedition.

If that little rat was planning—Mark hurried outside. The city was deathly quiet, immersed in sleep. The eternal light struck his eyes and brought him fully alert. He hurried along the street toward the outskirts, toward the base of the hill where the spaceship waited.

As he neared the hill, he spied Ferris. The man was coming down the slope. Ferris saw him, and waved a hand in greeting.

"Hi! Is it you, Travers? What's the matter, can't you sleep either?"

Mark's steps slowed, and he breathed in relief. He'd been wrong. After all, the man had a right to be up.

They met near the spaceship, and Ferris waved a hand toward the crest of the hill. "I was just looking at the Stone. It's the damnedest thing!"

"Yes. Brownell tells me—"

Ferris' hand moved like lightning. Mark found himself staring into the stub end of a neutro-gun. Ferris was no longer smiling and casual.

"In!" he snarled. "Get in there—quick!" He gestured toward the ship, and Mark noticed the door was open. He moved toward it slowly, then paused, started to turn.

"I'll blast you, Travers!"

Mark shrugged, entered. Ferris came quickly behind him.

"That's better. I don't want to rouse any of the others. Sounds carry far on this world." He paused and grinned, with all but his eyes. "Sure, Travers, I was looking at the Stone. I'd like to get it back to Earth, but it's too much for me. Guess I'll just have to be satisfied with the Frequency Tuner. The Bureau of Inventions will pay me a handsome price for it, no questions asked."

"You sneaking, double-crossing rat," Mark said slowly. "You'll never get away with this!"

"This says I will," Ferris sneered, gesturing with the neutro. "And since you came snooping out here, I'll just take that new weapon of yours."

"It doesn't work any more."

"I'll take it anyway. Hand it over. Careful!"

Mark shrugged, tossed the box-like weapon to him. But his mind was racing. Ferris had the upper hand, all right, and he would get away with this if Mark didn't do something quick. Mark glanced around. They were in the control room, and he knew the Frequency Tuner was ready. He said:

"What about Brownell—Janus—the others?"

"What about 'em? They wanted to come out here, so let 'em stay. Yeah—for the next hundred years!"

"What about me?"

"You know, I think I'll just take you along—for a short distance, anyway."

Mark's voice was taunting. "Because you're not quite sure how to handle this Frequency control. You'll need me."

"And that's where you're wrong. I've studied it plenty. It's easy!"

Mark dropped suddenly to his knees, and with the same movement his body lashed forward—low and hard. He heard the neutro sing, and felt the swirling heat of it over his shoulder. But Ferris was quick. He danced lithely back. His right hand with the gun in it came swinging up.

The heavy gun caught Mark squarely under the chin.

---

He came struggling back to consciousness, aware that he was still lying prone. He allowed his brain to clear before opening his eyes, but already he could tell they were in space.

He thought of his friends on Perlac—stranded! It would be a miracle if they ever succeeded in building another spaceship there, with their limited equipment.

"Hi, Travers. We're on our way. So I can't handle the Tuner, eh?"

Mark groaned, rolled his head a little, feigning grogginess. But he was alert now, and he cursed himself for a fool for underestimating Ferris. He heard the man's voice go on:

"And to show how much I need you, I'll just toss you out somewhere between Perlac and Pluto. Or maybe between Pluto and Neptune. Which would you prefer?"

Mark's heart leaped. They couldn't have come far, then! He was lying near the control-console and he knew they were on robot control. Ferris must have set the course already. He was confident now, watching Mark, for he knew it took minutes to adjust that complex set-up.

Mark stirred, grasped a metal stanchion to help hoist himself erect. His plan was made. To the right of the console was an auxiliary unit, feeding emergency power to the Tuner. He wondered if Ferris knew of it. He glimpsed Ferris coming toward him. Mark surged erect, his right hand darted out. It came down in a full sweep against the auxiliary impellator.

The spacer leaped ahead, sickeningly, as acceleration multiplied in a split second. Mark glimpsed Ferris flying backward. He hadn't time to see more. Both hands gripped the stanchion now as intolerable pressure built up. His arms seemed to be wrenching from their sockets. Slowly, agonizingly, he managed to encircle the stanchion with his left arm. His right hand seemed to weigh a ton as it reached out. It touched the impellator stud ... reversed it.

Mark sagged limply forward as acceleration lowered. He hadn't the strength left to turn his head, see what had happened to Ferris.

When he did, minutes later, he saw a limp figure against the far wall. The limbs were twisted beyond recognition. The head was crushed. It wasn't a pretty sight.

Mark changed direction, headed in a sweeping parabola back toward Perlac. He avoided Brownell's previous mistake and swung wide of the planet, approaching it from the light side. He landed safely near the city. The others had already missed the ship, and they received him joyously.

They left the next day, after a final check-up. Mari had prepared long lists of items for them to bring back to her people.

The robot-Ketrik was there too, to bid them bon voyage. Brownell said:

"Ketrik, you can reclaim that body of yours. Sure you won't change your mind and go back with us?"

Again Ketrik resorted to archaic expression:

"Are you kidding?" and he glanced at Mari with his huge robot eyes.

They lifted gravs, and not until they were crossing the orbit of Pluto did Brownell remember something. He chuckled, said to Mark:

"Suppose Ketrik does transfer again to his body, as he probably will. How's he going to transport it across that heavy gravity?"

For a moment Mark was startled. Then he grinned and replied, "Well, don't worry your mind over that. I'll bet you a thousand to one he'll do it! Positively. That man will find a way!"