He shuddered; then he began to explore the dome of the building for a means of entrance.

* * * * *

There was no opening in the roof. A solid sheet of reddish metal, like a titanic half-eggshell, it glittered under him in an unbroken piece.

He crept down its increasingly precipitous edge till he reached a sort of cornice that formed a jutting circle of stone around it. There he leaned far over and saw, about ten feet below him, a round opening like a big port-hole. From it were streaming waves of warm, foul air, from which he judged it to be a ventilator outlet.

He scrambled over the edge of the cornice, hung at arm's length, and swung himself down into the opening. And there, perched high up under the roof, he looked down at an enigmatic, eery scene.

That the structure was indeed a strange sort of power-house was instantly made evident. But what curious, mysterious, and yet bewilderingly simple machinery it held!

In the center was a titanic coil of reddish metal formed by a single cable nearly a yard through. Around this, at the four corners of the compass, were set coils that were identical in structure but a trifle smaller. From the smaller coils to the larger streamed, unceasingly, blue waves of light like lightning bolts.

Along a large arc of the wall was a stone slab set with an endless array of switches and insulated control-buttons. Gauges and indicators of all kinds, whose purpose could not even be guessed at, were lined above and below, all throbbing rhythmically to the leap of the electric-blue rays between the monster coils.

* * * * *

Almost under Brand's perch a great square beam of metal came through the building wall from outside, to be split into multitudinous smaller beams that were hooked up with the bases of the coils. Across from him, disappearing out through the opposite wall, was an identical beam.

"The terminals for the metal plate system that extends over the whole red spot," murmured Brand. "This building is important. But what can I do to throw sand in the gears before I'm caught and killed...?"

He surveyed the great round room below him more thoroughly. Now he saw, right in the center of the huge control board, a solitary lever, that seemed a sort of parent to all the other levers and switches. It was flanked by a perfect army of gauges and indicators; and was covered by a glass bell which was securely bolted to the rock slab.

"That looks interesting," Brand told himself. "I'd like to see that closer, if I can climb down from here without being observed.... Why"—he broke off—"where is everybody!"

For the first time, in the excitement and concentration of his purpose, the emptiness of the place struck him. There was no sign of light in the great building—no workmen or slaves anywhere. There was just the great coils, with the streamers of blue light bridging them and emitting the high-pitched, monotonous hum audible outside the dome, and the complicated control board with its quivering indicator needles and mysterious levers. That was all.

"Must be out to lunch," muttered Brand, his eyes going fascinatedly toward that solitary, parent lever under its glass bell. "Well, it gives me a chance to try some experiments, anyway."

* * * * *

It was about fifty feet from his perch to the floor; but a few feet to one side was a metal beam that extended up to help support the trussed weight of the roof. He jumped for this, and quickly slid down it.

He started on a run for the control board; but almost immediately he stopped warily to listen: it seemed to him that he had caught, faintly, the squeaking, high tones of Rogan conversation.

Miraculously, the sound seemed to come from a blank wall to his left. He crept forward to investigate....

The mystery was solved before he had gone very far. There was an opening in the wall leading off to an annex of some kind outside the dome building. The opening was concealed by a set-back, so that at first glance it had seemed part of the wall itself. From this opening drifted the chatter of Rogans.

Brand stole closer, finally venturing to peer into the room beyond from an angle where he himself could not be seen. And he found that his whimsical reference to "lunch" had contained a ghastly element of fact!

In that annex were several dozen of the teetering, attenuated Rogans, and an equal number of slaves. And the relation of the slaves and the Rogans was one that made Brand's skin crawl.

Each Rogan had stripped the tunic from the chest of his slave. Now, as Brand watched, each drew a keen blade from his belt, and made a shallow gash in the shrinking flesh. There were a few stifled screams—some of the slaves were women—but for the most part the slashing was endured in stoical silence. When red drops began to ooze forth, the Rogans stooped and applied their horrible little mouths to the incisions....

"The slimy devils!" Brand whispered hoarsely, at sight of that dreadful feeding. "The inhuman, monstrous vermin!"

But now one or two of the Rogans had begun to utter squeaks of satiation; and Brand hastened away from there and toward the control board again. He hadn't an idea of what he might accomplish when he reached it; he didn't know but that a touch of the significant looking parent-lever might blast him to bits; but he did know that he was going to raise absolute hell with something, somewhere, if he possibly could.

* * * * *

Swiftly he approached the great master-lever, protected by its bell of glass. (At least it looked like glass, for it was crystal clear and reflected gleamingly the blue light from the nearby coils). He tapped it experimentally with his knuckles....

At once pandemonium reigned in the great vaulted building. There was a siren-like screaming from a device he noticed for the first time attached under the domed roof. A clanging alarm split the air from half a dozen gongs set around the upper walls.

Squealing shouts sounded behind Brand. He whirled, and saw the Rogans, interrupted in their terrible meal, pouring in from the annex and racing toward him. Rage and fear distorted their hideous faces as they pointed first to the big lever and then at the escaped Earthman. They redoubled their efforts to get at him, their long unsteady legs covering the distance in great bounds.

Brand swore. Was he to be caught again before he had accomplished a certain thing? When he had already managed to win clear to his objective?

He hammered at the glass bell with his fists, but realized with the first blow that he was only wasting time trying to crack it bare-handed. He glanced quickly about and saw a metal bar propped up against the control board near him.

* * * * *

He sprang for it, grasped it as a club, and returned to the glass bell. Raising his arms high, he brought the thick metal bar down on the glass with all his strength.

With a force that almost wrenched his arms from their sockets, the bar rebounded from the glass bell, leaving it uncracked.

"Unbreakable!" groaned Brand.

Desperately he tried again, whirling the bar high over his head and bringing it smashing down. The result was the same as before as far as breaking the bell was concerned. But—a little trickle of crushed rock came from around the bolts in the slab to which the bell was fastened.

A third time be brought the bar down. The glass bell sagged a bit sway from the slab....

He had no chance for more assaults on it. The nearest Rogans had leaped for him. Slimy arms were coiling around him, while the loathsome sucker-disks tore at his unprotected face and throat.

Savagely Brand lashed out with the bar. It caved in a pair of the long, skinny legs, bringing a bloated round head down within reach. He smashed it with the bar, exulting grimly as the blow crumpled bone and flesh almost down to the little mouth which was yet carmine from its recent feeding.

The process seemed a sound one to Brand, unable as he was to reach the Rogans' heads that towered six feet above his own. Methodically, swinging the bar with the weight of his body behind it, he repeated the example. First a crash of the bar against a pair of legs, then the crushing in of the Rogan's head when he toppled with agonized squeals to the floor.

Again and again he crushed the life out of a Rogan with his one-two swing of the deadly bar. They were thinning down, now. They were wavering in their charges against the comparatively insignificant being from another planet who was defending himself so fiercely.

* * * * *

Finally one of their number turned and ran toward an exit, waving his four arms and adding his high-pitched alarms to the incessant ringing of the gongs and shrieks of the warning siren up under the roof. The rest rushed the Earthman in a body.

Steadily, almost joyfully, Brand fought on. He had expected to be annihilated by one of the Rogan shock-tubes long before now; but as yet there was no sign of any. Either these Rogan workmen were not privileged to carry the terrible things, or they were too occupied to think of going and getting them; anyhow, Brand was left free to wield his bar and continue crushing out the lives of the two-legged vermin that attacked him.

With almost a shock of surprise, he saw finally that he had battered their number down to three. At that he took the offensive himself. He rammed the bluntly pointed end of the bar almost through one writhing torso, broke the back of a second with a whistling blow, and tripped and exterminated the third almost in as many seconds. The creatures, without their death-tubes, were as helpless as crippled rats!

Panting, he turned again toward the loosened glass bell, and battered at it with the precious bar. Gradually the bolts that held it to the stone slab were wrenched out, till only one supported it. But at this point, from half a dozen set-back doorways, streams of infuriated Rogans began pouring into the building and toward him.

The one that had fled had come back with help.



CHAPTER VIII

Tremendous Odds

Like living spokes of a half-wheel, with the Earthman as the hub, the Rogans converged toward Brand, a howling roar outside indicating that there were hundreds more waiting to jam into the dome as soon as they were able. There were still no shock-tubes in evidence: evidently the worker who had gone for help had gathered the first Rogan citizens he had encountered on the streets. But the very numbers of the mob spelled defeat for Brand.

However, there was still the great lever behind him to yank away from its switch-socket. The glass bell was almost off now. With a last mad blow, he knocked loose the remaining bolt that held it. The bell clattered to the floor.

A concerted shriek came from the crowding Rogans as they saw the Earthman's hand close on the lever. Whatever effect the throwing of that master-switch could have, there was no doubt that they were extremely anxious to prevent it!

And now, in the rear of the crowding columns, appeared Rogans taller than the others, with an authoritative air, who waved before them, eager to unleash their power, batteries of the death-tubes.

Resigning himself to annihilation in the next instant, Brand pulled down hard on the lever.

* * * * *

The effect wrought by the throwing of that great switch was almost indescribable.

In a flash, as though all had been struck at once by a giant's hand, every Rogan in the mob shot toward the floor, long thin legs caving under him as if turned to water. Writhing feebly, they endeavored to get up, but could not; and, still weakly ferocious, began to creep toward the Earthman like huge-headed worms.

Brand himself had been thrown to the floor with the falling of that switch. He had felt as though an invisible ocean had been poured on him, weighting him down intolerably. To move arms or legs required enormous effort; and to get up on his feet again was like rising under a two-hundred-pound pack.

The movement of the switch, he saw, had cut off the gravity reducing apparatus of the Rogans—whatever that might consist of. They were now, abruptly, subjected to the full force of gravity exerted by Jupiter's great mass. They could no more stand erect on their tottering, lofty legs than they could fly.

But, though greatly handicapped by the gravity pull, they were still not entirely helpless. Like huge, long insects they continued to worm their way toward Brand, using their four arms and their boneless legs to help urge them over the flooring. And in their rear the Rogan guards struggled to lift their tubes and level them at the escaped prisoner.

Prompt to avoid that, Brand went down on his hands and knees. Thus he was shielded by the foremost crawling Rogans: the ones in the rear, with the tubes, could not raise themselves high enough to bore down over their fellows' heads at the Earthman.

Squatting on his knees, Brand awaited the first resolute crawlers. And, on his knees, whirling the now thrice weighty bar at heads that were conveniently low enough to be accessible, he began his last stand.

* * * * *

On the Rogans came, evidently determined, at any sacrifice of life, to get the Earthman away from that vital control board. And to right and left, crouching low to escape the tubes of the guards slowly crawling forward from the rear, Brand laid about him with the bar.

He got a little sick at the havoc he was wreaking on these slow-moving, gravity-crippled things: but remembrance of their grisly feeding habits, and the torture they must by now have inflicted on Dex, kept him flailing down on soft heads with undiminished effort.

With the gravity pull what it was, the Earthman was immeasurably stronger than any individual Rogan. For a time the contest was all in his favor. It was like killing slugs in a rose garden!

Nevertheless, these slugs were, after all, twelve feet long and possessed of intelligence, besides being hundreds in number. After a while the tide of battle began to turn in their favor.

Brand began to feel his arms ache burningly with the sustained effort of wielding a weapon that now weighed about twenty-five pounds. He knew he couldn't keep up the terrific strain much longer. And, in addition, he could see that the armed Rogans in the rear were steadily forging ahead among the unarmed attackers, till they soon must be in a position to blast him with their weapons.

Brand brought down his bar, with failing force but still deadly effect, on the loathsome face of the nearest Rogan, grunting with satisfaction as he saw it crumple into a shapeless mass. He thrust it, spear-like, into another face, and another.

Then, abruptly, he found himself weaponless.

Raising it high to bring it down on an attacker who was almost about to seize him, he felt the metal bar turn white hot, and dropped it with a cry as it seared the skin from the palms of his hands. Some Rogan guard in the rear had managed to train his tube on the bar; and in the instant of its rising had almost melted it.

* * * * *

Weaponless and helpless, Brand crawled slowly back before the tortuously advancing mob, keeping close enough to them to be shielded from the tubes of the rear guards. Without his club he knew the end was a matter of seconds.

He had an impulse to leap full into the mass of repulsive, crawling bodies and die fighting as his fists battered at the gruesome faces. But a second impulse, and a stronger one, was the blind instinct to preserve his life as long as possible.

Hesitantly, almost reluctantly, acting on the primitive instinct of self-preservation, he continued to back away from the advancing horde; away from the switch and toward the rear of the dome.

With the instant of his withdrawal, a Rogan turned toward the lever to push it back up into contact and release the red kingdom from the burden of Jupiter's unendurable gravity. And now ensued a curious struggle. The lever, placed for the convenience of creatures twelve feet or more tall, was about five feet from the floor. And the Rogan couldn't reach it!

* * * * *

Stubbornly he heaved and writhed in an effort to raise his inordinately heavy body from the floor to a point where one of the weaving arms could reach the switch. But the pipe-stem legs would not bear its weight. Each time it nearly reached the lever, only to fall feebly back again in a snarl of tangled limbs.

Meanwhile, Brand had flashed a quick look back over his shoulder to see, in the wall behind him, a metal door he hadn't noticed before. He found time for a flashing instant to wonder why there were no Rogans entering from that doorway, too; but it was a vain wonder, and it faded from his mind as the ever advancing, groping monsters before him kept crowding him back.

Instinctively he changed his course a trifle, to edge toward the metal door. Perhaps, behind it, there was sanctuary for a few moments. Perhaps he could force it open, spring out, and bar it again in the faces of the pursuing mob. It sounded improbable, but at least it offered him a slim chance where before no chance had seemed possible.

He reached the door at last, fumbled behind him and felt, high over his head, a massive sliding bolt.

* * * * *

In the spot Brand had left, the struggle to throw the gravity-lever back into closed contact position went on. The Rogan who was fruitlessly trying to reach up to it paused and said something to one near him. That one halted, and began to crawl toward him.

The two of them tried to reach it, one bracing the other and helping him pry his body up from the implacable pull of Jupiter's uninsulated mass. The top Rogan reached a little higher. The flesh sucker-disk that served as a hand almost grasped the lever, but failed by only a few inches.

A third Rogan crawled up. And now, with two arching their backs to help the other, the thing was done. The hose-like, groping arm went up and pushed the lever back into place.

The blue streamer began to hum and crackle from coil to coil again. The invisible weight that pressed down was released as once more the giant planet's gravity was nullified. The Rogans got eagerly to their feet and began to race toward Brand in their normal long bounds.

Brand, just cautiously rising, when the power went back on, found himself leaping five feet into the air with the excess of his muscular effort. And in that leap he saw the Rogans in the rear straighten up and point their tubes. However, also in that leap, his fumbling hand shot back the bolt that securely shut the metal door.

With a shout of defiance he jumped out of the door and slammed it shut after him, feeling it grow searing hot an instant later under the impact of the rays from the tubes that had been trained on him.

A stinging shock reached him through the metal, flinging him to the ground. He rolled out of its range and leaped to his feet to race away from there. Then, with a gasp, he flattened his body back against the wall of the dome building.

He was in the enclosure that held the gigantic, lizard-like thing that had nearly got him on his escape from the tower room.

He wheeled frantically to go back and face the Rogan death-tubes. Anything rather than wait while that mammoth heap of tiny-brained ferocity ran him down and tore him to shreds! But even as he turned, he heard the bolt shoot home on the inside of the door; heard vengeful squeals of triumph from his pursuers.

* * * * *

At the other end of the enclosure, near the foot of the tower building, the great lizard eyed him unblinkingly, its tremendous jaws gaping to reveal a cavernous mouth that was hideously lined with bright orange colored membrane. Then, squatting lower with every step it took, like a mountainous cat about to spring on its prey, it began to stalk on its tree-like legs toward the tiny creature that had leaped into its yard with it.

Brand whirled this way and that, mechanically seeking a way out. There was none. The walls of the great enclosure were not like the wall of the tower. Here were no rough hewn stones, with protruding ridges of mortar set between. These walls were as smooth as glass, and just as smooth was the curved wall of the dome building behind him.

The monstrous beast stalked nearer, almost on its belly now. As it advanced, the great tail stirred up a cloud of reddish dust, and left behind it a round deep depression in a surface already crisscrossed with a multitude of similar depressions. A bellowing hiss came from its gaping mouth, and it increased its pace to a thunderous, waddling rush.



CHAPTER IX

Into the Enclosure

In the torture chamber Dex wavered slowly back to consciousness to get the growing impression that he was being immersed in a bath of liquid fire. Burning, intolerable pain assailed him with increasing intensity as his senses clarified.

At last he groaned and opened his eyes, for the moment not knowing where he was nor how he had come to be there. He saw strange torture instruments and tall monstrosities with pumpkin-shaped heads surrounding him closely in a semicircle, and staring at him out of great, dull eyes.

Remembrance came back with a rush, and he gathered his muscles to spring at the hateful figures. But he could not move. At waist and throat, at wrists and ankles, were hoops of metal. He closed his eyes again while the burning waves of invisible fire shot through him recurrently from head to foot.

Dully he wondered that he was still alive. His last recollection had been of the Rogan leader pointing his shock-tube full at him, his shapeless countenance working with murderous fury. However, alive he was; and most unenviably so!

His hands, circumscribed to a few inches of movement by the bonds on his wrists, felt the smooth substance at his back. And with a thrill of horror he realized his position: he was crucified against the metal slab on which the slave had writhed in agony a short half hour ago.

Again he strained and tugged, vainly, to get free. Off to one side, pressed back against a huge glass experimental tank, he saw the beautiful Greca, her eyes wide with horror; and caught her frantic pleading message to her "Great White One."

* * * * *

The Rogan leader, squealing and grimacing, advanced toward the victim on the metal plate. One of the long arms went out and a sucker-disk was pressed to Dex's cheek. Dex quivered at the loathsome contact of that soft and slimy substance; then set his jaws to keep from groaning as the disk was jerked away, to carry with it a fragment of skin and flesh.

Gingerly, the tall leader felt the twitching, blackened stump of his blasted arm. Dex grinned mirthlessly at that: he'd struck one or two blows in his own defense, anyhow!

At sight of the Earthman's grin, an expression of defiance and grim joy that needed no interpreting to be understandable, the Rogan leader fairly danced with rage. His long arm went out to the switch beside the plate, and pulled it down another notch—just a little, not nearly to the current that had torn at the slave.

At the increased torment resulting from that slight movement of the regulating lever, Dex yelled aloud in spite of all his will power. It seemed as though his whole body were about to burst into self-generated flame. Every cell and fiber of him seemed on the verge of flying apart. He could feel his eyes start from his head, could feel every hair on his scalp stand up as though discharging electric sparks.

A minute or two of that and he would go mad! He cried out again, and twisted helplessly in his bonds. And then the terrible torture stopped.

The Rogan had not touched the switch—yet whatever sort of current it was that charged the plate was abruptly clicked off, as though someone at a distance had cut a wire or thrown a master-switch.

* * * * *

Simultaneously with its ceasing, an invisible, crushing sea seemed to envelope everything. Dex felt his body sag against his metal bonds as if it had been changed to lead.

Before him the Rogans, who had been crowding closer to watch gloatingly each grimace he made, shot doorward as though their pipe-stem legs had been swept from under them. The leader fell on the stump of his seared arm and, a deafening squeal of rage and pain came from his little mouth. His tube fell from his grasp and rolled over the floor half a dozen yards away from him.

Amazed, observing the stricken creatures only dimly through a haze of pain, Dex saw them struggle vainly to get up again, and heard them chattering excitedly to themselves. For the moment, in the face of this queer phenomenon, the prisoner seemed to be forgotten. And Dex was quick to seize the momentary advantage.

"Greca!" he called. "The tube! There—on the floor!"

The girl raised her head quickly, and followed his imploring gaze. Laboriously she started for the tube. At the same instant the Rogan leader began to feel around him for his lost weapon. Not finding it, he raised his head and glanced about for it. He saw the girl making her way toward it and, with a squeak of terror, began to crawl toward it himself.

* * * * *

He was not quick enough. The girl, though not nearly as active under the increased pull of gravity as a person of Earth might be, was yet more agile than the Rogans. And she was the faster mover in this tortuous, snail-like race. While the Rogan leader was still several feet away, she retrieved the shock-tube.

"Kill him!" begged Dex. "And all the rest of the filthy creatures!"

With feminine horror of the thing that faced her, Greca hesitated an instant—a hesitation almost long enough to be fatal. Then, just as the Rogan leader was reaching savagely out for her, she leveled the tube at him and turned it to its full power.

One last thin squeal came from the Rogan's mouth, a squeal that cracked abruptly at its height. What had been its gangling body drifted up in inky smoke.

"The others!" called Dex. "Quick! Before they get their weapons—"

Greca swept the death-tube in a short arc in front of her, over the bodies of the remaining Rogans, as if spraying plants with a hose. One after another, toppling in swift succession like grotesque falling dominoes, the creatures sagged to the floor and melted away. That one small part of Jupiter's red spot, at least, was cleared of Rogan population.

* * * * *

Long shudders racked Greca's body, and her lips were a bloodless line in her pallid face. But she did not go into womanly hysterics or swoon at the slaughter it had been her lot to inflict. Moving as quickly as she could, she went to the metal slab and began, with shaking fingers, to undo the fastenings that held Dex prisoner.

"Good girl," said Dex, patting her satiny bare shoulder as he stood free again. "You're a sport and a gentleman. You don't understand the terms? They're Earth words, Greca, that carry the highest praise a man can give a woman. But let's get out of here before another gang comes and takes us again. Where can we hide?"

"I don't know any hiding places," confessed Greca despairingly. "The Rogans swarm everywhere. We will be seen the moment we try to leave here."

"Well, we'll hunt for a hole, anyway," said Dex. He essayed to walk. What with the tendency of his muscles to jerk and collapse with the aftermath of the torture he had endured, and the sudden and inexplicable increase in gravity that bore him down, he made heavy going of it. "First we'll go up and get Brand."

"Yes, yes," said Greca, a soft glow in her clear blue eyes. "Let us go quickly."

She started toward the door, panting with the effort of moving. But Dex halted an instant, to stoop and pick up another of the tubes.

"We might as well have one of these apiece," he said. "You've proved you have the grit to use one; and maybe the dirty rats will think twice about rushing us if we each have a load of death in our hands."

* * * * *

They made their way out of the torture laboratory, and up the incline to the street level. And it was just as they reached this that the burden of gravity under which they staggered was lifted from their shoulders as quickly as it had descended on them.

Dex raised his arms just in time to fend his body from a collision with the wall in front of him. "Now what!" he exclaimed.

Greca lifted her hand for silence, inclined her head, and listened intently. As she did so, Dex heard the same noise her quick ears had caught an instant before his: a distant pandemonium of ringing gongs and siren shrieks, and squealing cries of a multitude of agitated Rogans.

"What the devil—" began Dex. But again Greca raised her hand to silence him, and listened once more. As she listened, her sea-blue eyes grew wider and wider with horror. Then, frantically, she began to race down a long corridor away from the street door.

Dex hastened to follow her. "What is it?" he demanded, when he had caught up to her flying little feet. "This is not the way up to the room where Brand—"

"Your friend is not there," she interrupted. She explained swiftly, distractedly: "From the shouts of the Rogans I learn that he got into the great dome building, somehow, and then was driven into the pen of the...."

Dex could not get the next term she used. But her telepathic message of the peril she mentioned formed in his mind clearly enough.

He got a flashing brain picture of a great, high-walled yard with a monster in it of the kind he had caught a close-range glimpse a short while before. Also, he saw a blurred, tiny figure, running from wall to wall, that was Greca's imagining of Brand and his efforts to escape the enormous beast.

"Good heavens!" groaned Dex. "Penned in with one of the things they showed me while I was stretched on the rack! Are you sure, Greca?"

She nodded, and tried to run faster. "This way," she gasped, turning down a passage to the left that ended in a massive metal door. "This leads to the enclosure. Oh, if only we can be in time!"

Her slim fingers tore at a massive bolt that secured the door. "Here," said Dex, wrenching it open for her. And they stepped out into thin sunlight, onto a hard surface of reddish ground that was crisscrossed with innumerable rounded furrows like the tracks old-fashioned, fifty-passenger airplane wheels used to make on soft landing fields.

* * * * *

Greca shrieked, and pointed to the far end of the enclosure. Down there, flattened against the wall of the dome building, was Brand. And waddling toward him with a tread that caused the ground to quiver, was a mate to the hideous creature the Rogans had used to terrify Dex in the torture chamber.

Dex leveled the tube he was carrying, swore, hit it frenziedly against his hand. "How do you work this damned thing, Greca—Oh! Like that! There—see if that puts a sting in your hide!"

The distant monster stopped its advance toward Brand. A raw white spot as big as a dinner plate leaped into being on one of its enormous hind legs. It whirled with an ear-splitting hiss, to see what thing was causing such pain in its rear. The frightful head whipped back at the end of the long neck, to nuzzle at the seared spot. Then the giant lizard turned toward Brand again.

A second time Dex pressed the central coil that formed the handle of the tube, as Greca had showed him how to do. A second time the ray shot down the field to flick a chunk of flesh weighing many pounds from the monster's flank. And this time it definitely abandoned the quarry behind it. With a scream like the keening of a dozen steam whistles, it charged back over its tracks toward the distant pigmies that were inflicting such exasperating punishment on it.

Dex swept the tube before him in a short half-circle. A smoking gash appeared suddenly in the vast fore-quarters of the monster. It stopped abruptly, its clawed feet plowing along the ground with the force of its momentum. An instant it stood there. Then, with its head swinging from side to side and lowered so that its looped neck dragged on the reddish, dusty ground, it began to back away from the source of its hurt, bellowing and hissing its rage and bewilderment.

"Brand!" shouted Dex. "This end! Run, while I hold the thing off!"

Brand began to race down the long enclosure, ten feet to a leap. The great lizard darted after him, like a cat after an escaping mouse; but a flick of the tube sent it bellowing and screaming back to its corner.

"Dex!" gasped Brand. "Thank God!"

For a moment he leaned, white and shaken, against the wall. Then Greca caught his hand in both of hers, and Dex put his arm supportingly around his shoulder. They retreated back through the doorway behind them, and slid the bolt across the metal door.



CHAPTER X

The "Tank Scheme"

"Thank God you came when you did," repeated Brand. Then, with a moment in which, figuratively, to get his feet back on earth, the wonder of Dex's appearance struck him.

"How did you manage to get away?" he asked. "I was sure—I thought—when they dragged you out of the tower room I wouldn't see you again—"

Rapidly Dex gave an account of his ordeal in the torture chamber, telling Brand in a few words how he had attempted to win free of the Rogans, how he had almost succeeded, only to be caught again and clamped to the death-plate on the wall.

"But just as the big fellow was about to cook me for good and all," he concluded, "something happened to the current, and to the gravity at the same time—"

"That was when I pulled the lever in the dome building!" exclaimed Brand.

He told of what had befallen him in the Rogan power-house. "That lever, Dex!" he said swiftly. "It's the keynote of the whole business. It absolutely controls the pull of gravity, and Lord knows what else besides. If we could only get at it again! Perhaps we could not only shut it off so that Jupiter's pull would function again, but also reverse the process so its gravity would be increased! Think what that would mean! Every Rogan in the red empire stretched out and immovable, possibly crushed in by his own weight!"

"It's a wonderful thought," sighed Dex; while Greca's eyes glowed with a sudden hope for her enslaved race, "but I don't see how we could ever—"

He stopped; and glanced in alarm down the passage behind them. Greca and Brand, hearing the same soft noise, whirled to look, too.

* * * * *

Far down the passage, just sneaking around the bend, was a group of Rogan guards, each armed with a death-tube.

"Back to the pen!" cried Brand.

He slid the bolt, and jerked the door open. They rushed into the walled enclosure again, the slamming of the door behind them cutting off the enraged squeals of the Rogans.

"This isn't going to mean anything but a short delay, I'm afraid," said Brand, clenching his fists in an agony of futility. "They'll be in here in a minute, and get us like trapped rats."

"Not before we get a lot of them," said Dex grimly.

"But that isn't enough, man! We don't want to die, no matter how decently we do it. We've won free, and stayed free this long; now, somehow, we've got to reach our ship and get back to Earth to warn them of the danger that hides here for our planet!"

He strode tensely up and down, smacking his fist into his palm. "The lever!" he exclaimed. "That lever! It's our only answer! If we could get to it.... But how can we? We couldn't break into the dome, now the Rogans are on the watch for us, with anything less than a charge of explosives. Or a tank. God, how I'd like to have an old-fashioned, fifty-ton army tank here now!"

Greca exclaimed aloud as Brand's fleeting mental picture of one of Earth's unwieldy, long-discarded war tanks registered on her brain.

"There is the great beast there," she said hesitantly, pointing a slim forefinger at the huge lizard that had backed into a far corner and was regarding them out of dull, savage eyes. Then she shook her head. "But that is impossible. Impossible!"

* * * * *

The men stared at her, with dawning realization in their minds. Then they gazed at each other.

"Of course," said Brand. "Of course! Greca, you're marvelous! Wish we had a tank? Why, we've got one! A four-legged mountain of meat that ought to be able to plow through the side of that dome like a battering ram through cardboard!"

"But it's not possible," replied Greca, her head dropping dejectedly. "My people, as driven slaves, till the fields with great animals that were trapped in the surrounding jungles. They harness other great animals to haul burdens. But none of the beasts are like this one. This kind cannot be tamed or harnessed. It is too ferocious. It is used only as a scourge of fear, to crush us into complete submission."

"Can't be tamed?" Brand said. "We'll see about that! Come on, Dex."

"Just a minute," said Dex. He flattened against the wall, motioning them to do the same. Then he leveled his tube at the door.

Slowly, cautiously, the door began to swing back; and the Rogan that Dex had heard fumbling with the bolt stuck his huge head out to locate the escaped prisoners.

Dex pressed the release coil of his tube. Without a sound, the Rogan slumped to the ground, a smoking cavity in its shoulders at the spot where its head had been set. In an instant the body, too, disappeared; an upward coiling wisp of black smoke marking its vanishing.

Another Rogan, tiptoeing out, met the same fate; and another. And then the door was banged shut again, and the bolt ground into place on the inside.

"That'll teach 'em to be careful how they try to rush us from that door," said Dex, through set teeth. "Now let's see if that tank scheme of ours can be worked."

* * * * *

He picked up a tube dropped by one of the Rogans, and handed it to Brand; showing him which coil to press to get full force, as Greca had in turn informed him.

"Down the field," commanded Brand. "We'll go about thirty yards apart, and try to herd this brute back through the walls of the dome building. Once it's inside, we'll try to rush to the lever before the Rogans can down us, and jam the thing past its terminal peg and into reverse action. I don't know that there is a reverse to it—but we can try.

"Greca dear,"—the girl started at the warmth of his thought, and a faint pink rose to her pale cheeks—"you'd better stay by my side. Your place as hostage-priestess of your people wouldn't save you if those devils catch you now. Besides, you can keep your tube leveled at the doorway as we go, and discourage any Rogans who might pluck up courage to try coming out again."

They started down the field toward the nightmare thing that snarled and hissed in its corner. On one side of the big enclosure walked Brand, with Greca close beside him, glancing continuously over her shoulder at the rear door, and holding her tube in readiness to check any charge the Rogans might attempt to make from the tower building. On the other side, keeping an equal pace, advanced Dex.

With tubes of death as whips, and with death for themselves set as the stake for which they gambled, they went about their attempt to drive the brainless monster before them through the solid wall of the dome building. And there followed what was probably the strangest animal act the universe has ever witnessed.

* * * * *

The first thing to do was to rout the enormous lizard out of the corner where sullen fear had sent it squatting. Dex contrived to do that by standing next to the wall at its side, and sending a searing ray that just touched the scaly, tremendously thick hide. The monster bellowed deafeningly, and, with a spot smoking on its flank, waddled sideways to the center of the field. Its head and swaying long neck faced the Earthmen and its back was against the wall of the dome building. To that extent, at least, they had the creature placed; but they soon found that the struggle had only just begun.

Brand got far enough around to focus his tube on the tip of the huge tail, in an effort to swing the gigantic thing about. There was an unearthly shriek from the colossal beast, and a foot and a half of its tail disappeared.

"Careful," called Dex, his jaw set and grim as the monster lashed out in its wrath. "If you bore in too long with that tube there'll be nothing left of our tank but a cloud of smoke."

Brand nodded, wordlessly, walking on the balls of his feet like a boxer, holding himself ready to swerve the thing should it charge them. Which—next instant—it did!

With a whistling bellow it gathered its tons of weight and thundered with incredible quickness at the gnats that were stinging its flanks and tail.

Desperately Brand played the tube across the vast chest, scoring a smouldering gash in the scale-covered flesh just above the gash Dex had seared a few moments before.

"Sorry, old fellow," Brand muttered to the screaming beast. "We hate to bait you like this, but it has to be done. Come on, now, through that wall behind you, and give us a chance at the lever."

* * * * *

But through the wall behind it the vast creature, not unnaturally, refused to go! It darted from side to side. Backward and forward. Up to the wall, only to back bewilderedly away from it. And constantly the tubes flicked their blistering, maddening rays along its monstrous sides and tail, as the Earthmen tried to guide it into the wall.

"Hope there's enough left of it to do the trick," said Brand, white-lipped. The monster was smoking in a dozen spots now, and several of the hump-like scales on its back had been burned away till the vast spine looked like a giant saw that was missing a third of its teeth. "God, I'm thinking we'll kill it before we can drive it through that wall!"

Greca nodded soberly, keeping her eyes on the distant door to their rear. Twice that door had been opened, and twice she had directed the death rays into its opening to mow down the gangling figures behind it. But she had said nothing of this to her man. He was busy enough with his own task!

"The door to the dome—" Dex shouted suddenly.

But Brand merely nodded, even as a discharge from his tube annihilated the Rogan that had appeared in the doorway before them. He had seen that door stealthily opening even before Dex had.

"It had better be soon, Dex!" he called. "Rogans in front of us—Rogans behind us—and—look out! On your side of the fence, there!"

Dex whirled in time to pick off a grotesque, pipe-like figure that had suddenly appeared on the broad wall of the enclosure. Then he turned to the frenzied problem of driving the monster through the building wall.

"The thing's going mad, Brand!" he cried, his voice high-pitched and brittle. "Watch out!"

* * * * *

It was only too evident that his statement was true. The baited monster, harried blindly this way and that, hounded against the blank wall behind it by something that bit chunks of living flesh out of its legs and sides, was losing whatever instinctive mental balance it had ever had. Its dimly functioning brain, probably no larger than a walnut in that gigantic skull, ceased more and more to guide it.

With a rasping scream that set the Earthmen's teeth on edge, it charged for the wall on Dex's side. Dex just managed to swerve it with a blast from the tube so prolonged that half its great lower jaw fell away.

At this the titanic thing went wholly, colossally mad! It whirled toward Brand, jerking around again as a searing on that side jarred its dull sensory nerves, then headed at last straight toward the stone wall of the dome building.

With the rays from both tubes flicking it like monstrous spurs, it charged insanely toward the bulge of the circular wall. With all its tons and tons of weight it crashed against the stonework. There was a thunderous crackling noise, and the wall sagged in perceptibly, while the metal roof bent to accommodate the new curvature of its supporting beams.

The monstrous lizard, jerked off its huge legs by the impact, staggered up and retreated toward the two men. But again the maddening pain in its hindquarters sent it careening toward the building wall. This time it raised high up on its hind legs in a blind effort to climb over it. "God, it must be five stories tall!" ejaculated Brand. Thunderingly its forelegs came down on the edge of the roof.

* * * * *

There was another deafening crash of stone and shrieking of torn metal. Just under the cornice, the wall sagged away from the roof and the top rows of heavy stone blocks slithered inward.

"Again!" shouted Brand.

His tube was pointing almost continuously now at the metal door leading from the dome building. The Rogans inside, at the shocks that were battering down a section of their great building, were all trying to get out to the yard at once. In a stream they rushed for the doorway. And in loathsome heaps they fell at the impact of the ray and shriveled to nothingness on the bombarded threshold.

"Once more—" Brand repeated, his voice hoarse and tense.

And as though the monster heard and understood, it rushed again with all its vast weight and force against the wall in a mad effort to escape the things that were blasting the living flesh from its colossal framework.

This charge was the last. With a roaring crash a section of the building thirty yards across went back and down, leaving the massive roof to sag threateningly on its battered truss-work.

* * * * *

It was as though the side of an ant-heap had been ripped away. Inside the domed building hundreds of Rogans ran this way and that on their elongated legs, squealing in their staccato, high-pitched tongue.

With blind fury the mad monster charged in through the gaping hole it had battered for itself. In all directions the Rogans scattered. Then an authoritative tall figure with a tube in each of its four sucker-disks, whipped out a command and pointed to the great coils which lay immediately in the berserk monster's path.

The command restored some sort of order. Losing their fear of the beast in their greater fear of the damage it might do, the Rogans massed to stop it before it could demolish the Rogan heart of power.

At this point Brand saw an opening of the kind he had been praying for. The Rogans had retreated before the terrific charge of the monster in such a way that the space between its vast bulk and the control board was clear.

"After me!" he shouted to Dex. "One of us has got to reach that lever while the creature's still there to shield us!"

The two Earthmen dashed through the jagged hole in the wall and raced to the control board just as the huge lizard, a smoking mass, sank to the floor. Brand gazed almost fearfully at the lever-slot.

Was there a reverse to the gravity-control action? There was room in the slot for the lever to be pulled down below the neutral point, if that meant anything....

* * * * *

Behind them the great bulk of the dead lizard was disappearing with incredible quickness under the rays of the tubes directed on it. Now the pumpkin-shaped heads on the opposite side were visible through a fleeting glimpse of a skeleton that was like the framework of a skyscraper. And now the colossal bones themselves were melting, while over everything hung a pall of greasy black smoke.

"Hurry, for God's sake!" gasped Dex.

Brand threw down the lever till it stuck. At once that invisible ocean poured crushingly over them, throwing them to their knees and sweeping the Rogans flat on their hideous faces just as half a hundred tubes were flashing down to point at the Earthmen.

"More—if you can!" grated Dex, whirling this way and that and spraying the massed Rogans with his death-dealing tube. Dozens went up in smoke under that discharge; but other dozens remained to raise themselves laboriously and slowly level their suddenly ponderous weapons at the Earthmen.

Brand set his jaw and threw all his weight on the lever. It bent a little, caught at the neutral point—and then jammed down an appreciable distance beyond it.

* * * * *

Instantly the blue streamers, that had stopped their humming progress from coil to coil with the movement of the switch to neutral, started again in reversed direction. And instantly the invisible ocean pressed down with appalling, devastating force.

Greca and Brand and Dex were flattened to the floor as if by blankets of lead. And the scattered Rogans about them ceased all movement whatever.

"Oh," sobbed Greca, fighting for breath. "Oh!"

"We can't stand this," panted Dex. "We've fixed the Rogans, all right. But we've fixed ourselves, too! That lever has to go up a bit."

Brand nodded, finding his head almost too heavy for his neck to move. Sweat beaded his forehead—sweat that trickled heavily off his face like drops of liquid metal.

With a tremendous struggle he got to his knees beneath the master-switch. There he found it impossible to raise his arms; but, leaning back against the control board and so getting a little support, he contrived to lift his body up enough to touch the down-slanting lever with his head and move it back along its slot a fraction of an inch. The giant coils hummed a note lower; and some of the smashing weight was relieved.

"That does it, I think," Brand panted, his voice husky with exhaustion and triumph.

He began to crawl laboriously toward the nearest street exit. "On our way!" he said vibrantly. "To the space ship! We leave for Earth at once!"

* * * * *

Slowly, fighting the sagging weight of their bodies, the two Earthmen inched their way to the street, helping Greca as they went. Among the sprawled forms of the Rogans they crept, with great dull eyes rolling helplessly to observe their progress, and with feeble squeals of rage and fear and malediction following their slow path.

On the street a strange and terrible sight met their eyes.

Strewn over the metal paving like wheat stalks crushed flat by a hurricane, were thousands of Rogans. Not a muscle of their pipe-like arms or legs could they move. But the gravity that crushed them rigidly to the ground did not quite hold motionless the shorter and more sturdily built slaves.

Among the thousands of squealing, panting Rogans that lay as though paralyzed on the metal paving, crawled equal thousands of Greca's enslaved people. Their eyes flamed with fanatic hate. And methodically—not knowing what had caused their loathed masters to be stricken helpless, and not caring as long as they were helpless—the slaves were seeking out the shock-tubes that here and there had fallen from the clutch of Rogan guards. Already many had found them; and everywhere gangling, slimy bodies were melting in oily black smoke that almost instantly vanished in thin air.

As it was in these streets and in the great square in the center of which rested the Earthmen's ship, just so, they knew, was it being repeated all over the red empire. Slowly crawling, fiercely exulting slaves were exterminating the tyrannous things that had held them so long in dreadful bondage! Before the sun should set on another flashing Jovian day there would be no Rogan left in the red spot.

* * * * *

"And so it ends," said Brand with a great sigh. He moved over beside Greca, and touched her lovely bare shoulders. They were shaking convulsively, those shoulders; and she had buried her face in her hands to keep from gazing at the ghastly carnage.

Brand pressed her to him. "It's terrible—yes. But think what it means! The knell of all the Rogans been sounded to-day. As soon as the secret of these death-tubes has been analyzed by our science and provided against, my friend and I will return from Earth with a force that shall clear the universe of the slimy devils. Meanwhile, your people are safe here; with the gravity what it is, no Rogan attacking hordes can land."

They crawled tortuously over the square to the space ship. Brand turned again to Greca; and now in his eyes was a look that needed no language of mind or tongue for its complete expression.

"Will you come to Earth with me, Greca, and stay by my side till we return to set your people in power again?"

Greca shook her head, slowly, reluctantly. "My people need leaders now. I must stay and help direct them in their new freedom. But you—you'll come back with the others from Earth?"

"Try and stop him!" grinned Dex. "And try and stop me, too! From what I know now of the way they grow 'em on your satellite"—his eyes rested on Greca's beauty with an admiration that turned her to rosy confusion—"I'd say I'd found the ideal spot to settle down in!"

Brand laughed. "He's answered for me too. And now, a salute that is used on Earth to express a promise...." He kissed her—to her utter astonishment and perplexity, but to her dawning pleasure. "Good-by for a little while."

The two Earthmen hoisted themselves heavily over the sill of the control room of their ship, and crawled inside.

They secured the trap-door, and turned on the air-rectifiers. Brand moved to the controls, waved to Greca, who was smiling at him through the glass panel, and pointed the ship on its triumphant, four hundred million mile journey home.

* * * * *

THE END