here was no use hiding from the truth. Somebody had blundered—a fatal blunder—and they were going to pay for it! Mark Forepaugh kicked the pile of hydrogen cylinders. Only a moment ago he had broken the seals—the mendacious seals that certified to the world that the flasks were fully charged. And the flasks were empty! The supply of this precious power gas, which in an emergency should have been sufficient for six years, simply did not exist.

He walked over to the integrating machine, which as early as the year 2031 had begun to replace the older atomic processes, due to the shortage of the radium series metals. It was bulky and heavy compared to the atomic disintegrators, but it was much more economical and very dependable. Dependable—provided some thick-headed stock clerk at a terrestrial supply station did not check in empty hydrogen cylinders instead of full ones. Forepaugh's unwonted curses brought a smile to the stupid, good-natured face of his servant, Gunga—he who had been banished for life from his native Mars for his impiety in closing his single round eye during the sacred Ceremony of the Wells.

The Earth man was at this steaming hot, unhealthful trading station under the very shadow of the South Pole of the minor planet Inra for an entirely different reason. One of the most popular of his set on the Earth, an athletic hero, he had fallen in love, and the devoutly wished-for marriage was only prevented by lack of funds. The opportunity to take charge of this richly paid, though dangerous, outpost of civilization had been no sooner offered than taken. In another week or two the relief ship was due to take him and his valuable collection of exotic Inranian orchids back to the Earth, back to a fat bonus, Constance, and an assured future.

It was a different young man who now stood tragically before the useless power plant. His slim body was bowed, and his clean features were drawn. Grimly he raked the cooling dust that had been forced in the integrating chamber by the electronic rearrangement of the original hydrogen atoms—finely powdered iron and silicon—the "ashes" of the last tank of hydrogen.

unga chuckled.

"What's the matter?" Forepaugh barked. "Going crazy already?"

"Me, haw! Me, haw! Me thinkin'," Gunga rumbled. "Haw! We got, haw! plenty hydr'gen." He pointed to the low metal roof of the trading station. Though it was well insulated against sound, the place continually vibrated to the low murmur of the Inranian rains that fell interminably through the perpetual polar day. It was a rain such as is never seen on Earth, even in the tropics. It came in drops as large as a man's fist. It came in streams. It came in large, shattering masses that broke before they fell and filled the air with spray. There was little wind, but the steady green downpour of water and the brilliant continuous flashing of lightning shamed the dull soggy twilight produced by the large, hot, but hidden sun.

"Your idea of a joke!" Forepaugh growled in disgust. He understood what Gunga's grim pleasantry referred to. There was indeed an incalculable quantity of hydrogen at hand. If some means could be found to separate the hydrogen atoms from the oxygen in the world of water around them they would not lack for fuel. He thought of electrolysis, and relaxed with a sigh. There was no power. The generators were dead, the air drier and cooler had ceased its rhythmic pulsing nearly an hour ago. Their lights were gone, and the automatic radio utterly useless.

"This is what comes of putting all your eggs in one basket," he thought, and let his mind dwell vindictively on the engineers who had designed the equipment on which his life depended.

An exclamation from Gunga startled him. The Martian was pointing to the ventilator opening, the only part of this strange building that was not hermetically sealed against the hostile life of Inra. A dark rim had appeared at its margin, a loathsome, black-green rim that was moving, spreading out. It crept over the metal walls like the low-lying smoke of a fire, yet it was a solid. From it emanated a strong, miasmatic odor.

"The giant mold!" Forepaugh cried. He rushed to his desk and took out his flash pistol, quickly set the localizer so as to cover a large area. When he turned he saw, to his horror, Gunga about to smash into the mold with his ax. He sent the man spinning with a blow to the ear.

"Want to scatter it and start it growing in a half-dozen places?" he snapped. "Here!"

e pulled the trigger. There was a light, spiteful "ping" and for an instant a cone of white light stood out in the dim room like a solid thing. Then it was gone, and with it was gone the black mold, leaving a circular area of blistered paint on the wall and an acrid odor in the air. Forepaugh leaped to the ventilating louver and closed it tightly.

"It's going to be like this from now on," he remarked to the shaken Gunga. "All these things wouldn't bother us as long as the machinery kept the building dry and cool. They couldn't live in here. But it's getting damp and hot. Look at the moisture condensing on the ceiling!"

Gunga gave a guttural cry of despair. "It knows, Boss; look!"

Through one of the round, heavily framed ports it could be seen, the lower part of its large, shapeless body half-floating in the lashing water that covered their rocky shelf to a depth of several feet, the upper part spectral and gray. It was a giant amoeba, fully six feet in diameter in its present spheroid form, but capable of assuming any shape that would be useful. It had an envelope of tough, transparent matter, and was filled with a fluid that was now cloudy and then clear. Near the center there was a mass of darker matter, and this was undoubtedly the seat of its intelligence.

The Earth man recoiled in horror! A single cell with a brain! It was unthinkable. It was a biological nightmare. Never before had he seen one—had, in fact, dismissed the stories of the Inranian natives as a bit of primitive superstition, had laughed at these gentle, stupid amphibians with whom he traded when they, in their imperfect language, tried to tell him of it.

They had called it the Ul-lul. Well, let it be so. It was an amoeba, and it was watching him. It floated in the downpour and watched him. With what? It had no eyes. No matter, it was watching him. And then it suddenly flowed outward until it became a disc rocking on the waves. Again its fluid form changed, and by a series of elongations and contractions it flowed through the water at an incredible speed. It came straight for the window, struck the thick, unbreakable glass with a shock that could be felt by the men inside. It flowed over the glass and over the building. It was trying to eat them, building and all! The part of its body over the port became so thin that it was almost invisible. At last, its absolute limit reached, it dropped away, baffled, vanishing amid the glare of the lightning and the frothing waters like the shadows of a nightmare.

he heat was intolerable and the air was bad.

"Haw, we have to open vent'lator, Boss!" gasped the Martian.

Forepaugh nodded grimly. It wouldn't do to smother either. Though to open the ventilator would be to invite another invasion by the black mold, not to mention the amoebae and other fabulous monsters that had up to now been kept at a safe distance by the repeller zone, a simple adaptation of a very old discovery. A zone of mechanical vibrations, of a frequency of 500,000 cycles per second, was created by a large quartz crystal in the water, which was electrically operated. Without power, the protective zone had vanished.

"We watch?" asked Gunga.

"You bet we watch. Every minute of the 'day' and 'night.'"

He examined the two chronometers, assuring himself that they were well wound, and congratulated himself that they were not dependent on the defunct power plant for energy. They were his only means of measuring the passage of time. The sun, which theoretically would seem to travel round and round the horizon, rarely succeeded in making its exact location known, but appeared to shift strangely from side to side at the whim of the fog and water.

"Th' fellas," Gunga remarked, coming out of a study. "Why not come?" He referred to the Inranians.

"Probably know something's wrong. They can tell the quartz oscillator is stopped. Afraid of the Ul-lul, I suppose."

"'Squeer," demurred the Martian. "Ul-lul not bother fellas."

"You mean it doesn't follow them into the underbrush. But it would find tough going there. Not enough water; trees there, four hundred feet high with thorny roots and rough bark—they wouldn't like that. Oh no, these natives ought to be pretty snug in their dens. Why, they're as hard to catch as a muskrat! Don't know what a muskrat is, huh? Well, it's the same as the Inranians, only different, and not so ugly."

or the next six days they existed in their straitened quarters, one guarding while the other slept, but such alarms as they experienced were of a minor nature, easily disposed of by their flash pistol. It had not been intended for continuous service, and under the frequent drains it showed an alarming loss of power. Forepaugh repeatedly warned Gunga to be more sparing in its use, but that worthy persisted in his practice of using it against every trifling invasion of the poisonous Inranian cave moss that threatened them, or the warm, soggy water-spiders that hopefully explored the ventilator shaft in search of living food.

"Bash 'em with a broom, or something! Never mind if it isn't nice. Save our flash gun for something bigger."

Gunga only looked distressed.

On the seventh day their position became untenable. Some kind of sea creature, hidden under the ever-replenished storm waters, had found the concrete emplacements of their trading post to its liking. Just how it was done was never learned. It is doubtful that the creatures could gnaw away the solid stone—more likely the process was chemical, but none the less it was effective. The foundations crumbled; the metal shell subsided, rolled half over so that silty water leaked in through the straining seams, and threatened at any moment to be buffeted and urged away on the surface of the flood toward that distant vast sea which covers nine-tenths of the area of Inra.

"Time to mush for the mountains," Forepaugh decided.

Gunga grinned. The Mountains of Perdition were, to his point of view, the only part of Inra even remotely inhabitable. They were sometimes fairly cool, and though perpetually pelted with rain, blazing with lightning and reverberating with thunder, they had caves that were fairly dry and too cool for the black mold. Sometimes, under favorable circumstances on their rugged peaks, one could get the full benefit of the enormous hot sun for whose actinic rays the Martian's starved system yearned.

"Better pack a few cans of the food tablets," the white man ordered. "Take a couple of waterproof sleeping bags for us, and a few hundred fire pellets. You can have the flash pistol; it may have a few more charges in it."

orepaugh broke the glass case marked "Emergency Only" and removed two more flash pistols. Well he knew that he would need them after passing beyond the trading area—perhaps sooner. His eyes fell on his personal chest, and he opened it for a brief examination. None of the contents seemed of any value, and he was about to pass when he dragged out a long, heavy, .45 caliber six-shooter in a holster, and a cartridge belt filled with shells. The Martian stared.

"Know what it is?" his master asked, handing him the weapon.

"Gunga not know." He took it and examined it curiously. It was a fine museum piece in an excellent state of preservation, the metal overlaid with the patina of age, but free from rust and corrosion.

"It's a weapon of the Ancients," Forepaugh explained. "It was a sort of family heirloom and is over 300 years old. One of my grandfathers used it in the famous Northwest Mounted Police. Wonder if it'll still shoot."

He leveled the weapon at a fat, sightless wriggler that came squirming through a seam, squinting unaccustomed eyes along the barrel. There was a violent explosion, and the wriggler disappeared in a smear of dirty green. Gunga nearly fell over backward in fright, and even Forepaugh was shaken. He was surprised that the ancient cartridge had exploded at all, though he knew powder making had reached a high level of perfection before explosive chemical weapons had yielded to the newer, lighter, and infinitely more powerful ray weapons. The gun would impede their progress. It would be of very little use against the giant Carnivora of Inra. Yet something—perhaps a sentimental attachment, perhaps what his ancestors would have called a "hunch"—compelled him to strap it around his waist. He carefully packed a few essentials in his knapsack, together with one chronometer and a tiny gyroscopic compass. So equipped, they could travel with a fair degree of precision toward the mountains some hundred miles on the other side of a steaming forest, a-crawl with feral life, and hot with blood-lust.

an and master descended into the warm waters and, without a backward glance, left the trading post to its fate. There was not even any use in leaving a note. Their relief ship, soon due, would never find the station without radio direction.

The current was strong, but the water gradually became shallower as they ascended the sloping rock. After half an hour they saw ahead of them the loom of the forest, and with some trepidation they entered the gloom cast by the towering, fernlike trees, whose tops disappeared in murky fog. Tangled vines impeded their progress. Quagmires lay in wait for them, and tough weeds tripped them, sometimes throwing one or another into the mud among squirming small reptiles that lashed at them with spiked, poisonous feet and then fell to pieces, each piece to lie in the bubbling ooze until it grew again into a whole animal.

Several times they almost walked under the bodies of great, spheroidal creatures with massive short legs, whose tremendously long, sinuous necks disappeared in the leafy murk above, swaying gently like long-stalked lilies in a terrestial pond. These were azornacks, mild-tempered vegetarians whose only defense lay in their thick, blubbery hides. Filled with parasites, stinking and rancid, their decaying covering of fat effectively concealed the tender flesh underneath, protecting them from fangs and rending claws.

Deeper in the forest the battering of the rain was mitigated. Giant neo-palm leaves formed a roof that shut out not only most of the weak daylight, but also the fury of the downpour. The water collected in cataracts, ran down the boles of the trees, and roared through the semi-circular canals of the snake trees, so named by early explorers for their waving, rubbery tentacles, multiplied a millionfold, that performed the duties of leaves. Water gurgled and chuckled everywhere, spread in vast dim ponds and lakes writhing with tormented roots, up-heaved by unseen, uncatalogued leviathans, rippled by translucent discs of loathsome, luminescent jelly that quivered from place to place in pursuit of microscopic prey.

Yet the impression was one of calm and quiet, and the waifs from other worlds felt a surcease of nervous tension. Unconsciously they relaxed. Taking their bearings, they changed their course slightly for the nesting place of the nearest tribe of Inranians where they hoped to get food and at least partial shelter; for their food tablets had mysteriously turned to an unpleasant viscous liquid, and their sleeping bags were alive with giant bacteria easily visible to the eye.

hey were doomed to disappointment. After nearly twelve hours of desperate struggling through the morass, through gloomy aisles, and countless narrow escapes from prowling beasts of prey in which only the speed and tremendous power of their flash pistols saved them from instant death, they reached a rocky outcropping which led to the comparatively dry rise of land on which a tribe of Inranians made its home. Their faces were covered with welts made by the hanging filaments of blood-sucking trees as fine as spider webs, and their senses reeled with the oppressive stench of the abysmal jungle. If the pampered ladies of the Inner Planets only knew where their thousand-dollar orchids sprang from!

Converging runways showed the opening of one of the underground dens, almost hidden from view by a bewildering maze of roots, rendered more formidable by long, sharp stakes made from the iron-hard thigh-bones of the flying kabo.

Forepaugh cupped his hands over his mouth and gave the call.

"Ouf! Ouf! Ouf! Ouf! Ouf!"

He repeated it over and over, the jungle giving back his voice in a muffled echo, while Gunga held a spare flash pistol and kept a sharp lookout for a carnivore intent on getting an unwary Inranian.

There was no answer. These timid creatures, who are often rated the most intelligent life native to primitive Inra, had sensed disaster and had fled.

Forepaugh and Gunga slept in one of the foul, poorly ventilated dens, ate of the hard, woody tubers that had not been worth taking along, and wished they had a certain stock clerk at that place at that time. They were awakened out of deep slumber by the threshing of an evil looking creature which had become entangled among the sharpened spikes. Its tremendous maw, splitting it almost in half, was opened in roars of pain that showed great yellow fangs eight inches in length. Its heavy flippers battered the stout roots and lacerated themselves in the beast's insensate rage. It was quickly dispatched with a flash pistol and Gunga cooked himself some of the meat, using a fire pellet; but despite his hunger Forepaugh did not dare eat any of it, knowing that this species, strange to him, might easily be one of the many on Inra that are poisonous to terrestials.

hey resumed their march toward the distant invisible mountains, and were fortunate in finding somewhat better footing than they had on their previous march. They covered about 25 miles on that "day," without untoward incident. Their ray pistols gave them an insuperable advantage over the largest and most ferocious beasts they could expect to meet, so that they became more and more confident, despite the knowledge that they were rapidly using up the energy stored in their weapons. The first one had long ago been discarded, and the charge indicators of the other two were approaching zero at a disquieting rate. Forepaugh took them both, and from that time on he was careful never to waste a discharge except in case of a direct and unavoidable attack. This often entailed long waits or stealthy detours through sucking mud, and came near to ending both their lives.

The Earth man was in the lead when it happened. Seeking an uncertain footing through a tangle of low-growing, thick, ghastly white vegetation, he placed a foot on what seemed to be a broad, flat rock projecting slightly above the ooze. Instantly there was a violent upheaval of mud; the seeming rock flew up like a trap-door, disclosing a cavernous mouth some seven feet across, and a thick, triangular tentacle flew up from its concealment in the mud in a vicious arc. Forepaugh leaped back barely in time to escape being swept in and engulfed. The end of the tentacle struck him a heavy blow on the chest, throwing him back with such force as to bowl Gunga over, and whirling the pistols out of his hands into a slimy, bulbous growth nearby, where they stuck in the phosphorescent cavities the force of their impact had made.

here was no time to recover the weapons. With a bellow of rage the beast was out of its bed and rushing at them. Nothing stayed its progress. Tough, heavily scaled trees thicker than a man's body shuddered and fell as its bulk brushed by them. But it was momentarily confused, and its first rush carried it past its dodging quarry. This momentary respite saved their lives.

Rearing its plumed head to awesome heights, its knobby bark running with brown rivulets of water, a giant tree, even for that world of giants, offered refuge. The men scrambled up the rough trunk easily, finding plenty of hand and footholds. They came to rest on one of the shelflike circumvoluting rings, some twenty-five feet above the ground. Soon the blunt brown tentacles slithered in search of them, but failed to reach their refuge by inches.

And now began the most terrible siege that interlopers in that primitive world can endure. From that cavernous, distended throat came a tremendous, world-shaking noise.

"HOOM! HOOM! HOOM! HOOM! HOOM! HOOM!"

Forepaugh put his hand to his head. It made him dizzy. He had not believed that such noise could be. He knew that no creature could long live amidst it. He tore strips from his shredded clothing and stuffed his ears, but felt no relief.

"HOOM! HOOM! HOOM! HOOM! HOOM!"

It throbbed in his brain.

Gunga lay a-sprawl, staring with fascinated eye into the pulsating scarlet gullet that was blasting the world with sound. Slowly, slowly he was slipping. His master hauled him back. The Martian grinned at him stupidly, slid again to the edge.

Once more Forepaugh pulled him back. The Martian seemed to acquiesce. His single eye closed to a mere slit. He moved to a position between Forepaugh and the tree trunk, braced his feet.

"No you don't!" The Earth man laughed uproariously. The din was making him light-headed. It was so funny! Just in time he had caught that cunning expression and prepared for the outlashing of feet designed to plunge him into the red cavern below and to stop that hellish racket.

"And now—"

He swung his fist heavily, slamming the Martian against the tree. The red eye closed wearily. He was unconscious, and lucky.

Hungrily the Earth man stared at his distant flash pistols, plainly visible in the luminescence of their fungus bedding. He began a slow, cautious creep along the top of a vine some eight inches thick. If he could reach them....

rash! He was almost knocked to the ground by the thud of a frantic tentacle against the vine. His movement had been seen. Again the tentacle struck with crushing force. The great vine swayed. He managed to reach the shelf again in the very nick of time.

"HOOM! HOOM! HOOM! HOOM! HOOM!"

A bolt of lightning struck a giant fern some distance away. The crash of thunder was hardly noticeable. Forepaugh wondered if his tree would be struck. Perhaps it might even start a fire, giving him a flaming brand with which to torment his tormentor. Vain hope! The wood was saturated with moisture. Even the fire pellets could not make it burn.

"HOOM! HOOM! HOOM! HOOM! HOOM! HOOM! HOOM!"

The six-shooter! He had forgotten it. He jerked it from its holster and pointed it at the red throat, emptied all the chambers. He saw the flash of yellow flame, felt the recoil, but the sound of the discharges was drowned in the Brobdignagian tumult. He drew back his arm to throw the useless toy from him. But again that unexplainable, senseless "hunch" restrained him. He reloaded the gun and returned it to its holster.

"HOOM! HOOM! HOOM! HOOM! HOOM! HOOM!"

A thought had been struggling to reach his consciousness against the pressure of the unbearable noise. The fire pellets! Couldn't they be used in some way? These small chemical spheres, no larger than the end of his little finger, had long ago supplanted actual fire along the frontiers, where electricity was not available for cooking. In contact with moisture they emitted terrific heat, a radiant heat which penetrated meat, bone, and even metal. One such pellet would cook a meal in ten minutes, with no sign of scorching or burning. And they had several hundred in one of the standard moisture-proof containers.

s fast as his fingers could work the trigger of the dispenser Forepaugh dropped the potent little pellets down the bellowing throat. He managed to release about thirty before the bellowing stopped. A veritable tornado of energy broke loose at the foot of the tree. The giant maw was closed, and the shocking silence was broken only by the thrashing of a giant body in its death agonies. The radiant heat, penetrating through and through the beast's body, withered nearby vegetation and could be easily felt on the perch up the tree.

Gunga was slowly recovering. His iron constitution helped him to rally from the powerful blow he had received, and by the time the jungle was still he was sitting up mumbling apologies.

"Never mind," said his master. "Shin down there and cut us off a good helping of roast tongue, if it has a tongue, before something else comes along and beats us out of a feast."

"Him poison, maybe," Gunga demurred. They had killed a specimen new to zoologists.

"Might as well die of poison as starvation," Forepaugh countered.

Without more ado the Martian descended, cut out some large, juicy chunks as his fancy dictated, and brought his loot back up the tree. The meat was delicious and apparently wholesome. They gorged themselves and threw away what they could not eat, for food spoils very quickly in the Inranian jungles and uneaten meat would only serve to attract hordes of the gauzy-winged, glutinous Inranian swamp flies. As they sank into slumber they could hear the beginning of a bedlam of snarling and fighting as the lesser Carnivora fed on the body of the fallen giant.

When they awoke the chronometer recorded the passing of twelve hours, and they had to tear a network of strong fibers with which the tree had invested them preparatory to absorbing their bodies as food. For so keen is the competition for life on Inra that practically all vegetation is capable of absorbing animal food directly. Many an Inranian explorer can tell tales of narrow escapes from some of the more specialized flesh-eating plants; but they are now so well known that they are easily avoided.

clean-picked framework of crushed and broken giant bones was all that was left of the late bellowing monster. Six-legged water dogs were polishing them hopefully, or delving into them with their long, sinuous snouts for the marrow. The Earth man fired a few shots with his six-shooter, and they scattered, dragging the bodies of their fallen companions to a safe distance to be eaten.

Only one of the flash pistols was in working order. The other had been trampled by heavy hoofs and was useless. A heavy handicap under which to traverse fifty miles of abysmal jungle. They started with nothing for breakfast except water, of which they had plenty.

Fortunately the outcroppings of rocks and gravel washes were becoming more and more frequent, and they were able to travel at much better speed. As they left the low-lying jungle land they entered a zone which was faintly reminiscent of a terrestial jungle. It was still hot, soggy, and fetid, but gradually the most primitive aspects of the scene were modified. The over-arching trees were less closely packed, and they came across occasional rock clearings which were bare of vegetation except for a dense carpet of brown, lichenlike vegetation that secreted an astonishing amount of juice. They slipped and sloshed through this, rousing swarms of odd, toothed birds, which darted angrily around their heads and slashed at them with the razor-sharp saw edges on the back of their legs. Annoying as they were, they could be kept away with branches torn from trees, and their presence connoted an absence of the deadly jungle flesh-eaters, permitting a temporary relaxation of vigilance and saving the resources of the last flash gun.

They camped that "night" on the edge of one of these rock clearings. For the first time in weeks it had stopped raining, although the sun was still obscured. Dimly on the horizon could be seen the first of the foothills. Here they gathered some of the giant, oblong fungus that early explorers had taken for blocks of porous stone because of their size and weight, and, by dint of the plentiful application of fire pellets, managed to set it ablaze. The heat added nothing to their comfort, but it dried them out and allowed them to sleep unmolested.

n unwary winged eel served as their breakfast, and soon they were on their way to those beckoning hills. It had started to rain again, but the worst part of their journey was over. If they could reach the top of one of the mountains there was a good chance that they would be seen and rescued by their relief ship, provided they did not starve first. The flyer would use the mountains as a base from which to search for the trading station, and it was conceivable that the skipper might actually have anticipated their desperate adventure and would look for them in the Mountains of Perdition.

They had crossed several ranges of the foothills and were beginning to congratulate themselves when the diffused light from above was suddenly blotted out. It was raining again, and above the echo-augmented thunder they heard a shrill screeching.

"A web serpent!" Gunga cried, throwing himself flat on the ground.

Forepaugh eased into a rock cleft at his side. Just in time. A great grotesque head bore down upon him, many-fanged as a medieval dragon. Between obsidian eyes was a fissure whence emanated a wailing and a foul odor. Hundreds of short, clawed legs slithered on the rocks under a long sinuous body. Then it seemed to leap into the air again. Webs grew taut between the legs, strumming as they caught a strong uphill wind. Again it turned to the attack, and missed them. This time Forepaugh was ready for it. He shot at it with his flash pistol.

othing happened. The fog made accurate shooting impossible, and the gun lacked its former power. The web serpent continued to course back and forth over their heads.

"Guess we'd better run for it," Forepaugh murmured.

"Go 'head!"

They cautiously left their places of concealment. Instantly the serpent was down again, persistent if inaccurate. It struck the place of their first concealment and missed them.

"Run!"

They extended their weary muscles to the utmost, but it was soon apparent that they could not escape long. A rock wall in their path saved them.

"Hole!" the Martian gasped.

Forepaugh followed him into the rocky cleft. There was a strong draft of dry air, and it would have been next to impossible to hold the Martian back, so Forepaugh allowed him to lead on toward the source of the draft. As long as it led into the mountains he didn't care.

The natural passageway was untenanted. Evidently its coolness and dryness made it untenable for most of Inra's humidity and heat loving life. Yet the floor was so smooth that it must have been artificially leveled. Faint illumination was provided by the rocks themselves. They appeared to be covered by some microscopic phosphorescent vegetation.

After hundreds of twists and turns and interminable straight galleries the cleft turned more sharply upward, and they had a period of stiff climbing. They must have gone several miles and climbed at least 20,000 feet. The air became noticeably thin, which only exhilarated Gunga, but slowed the Earth man down. But at last they came to the end of the cleft. They could go no further, but above them, at least 500 feet higher, they saw a round patch of sky, miraculously bright blue sky!

"A pipe!" Forepaugh cried.

He had often heard of these mysterious, almost fabulous structures sometimes reported by passing travelers. Straight and true, smooth as glass and apparently immune to the elements, they had been occasionally seen standing on the very tops of the highest mountains—seen for a few moments only before they were hidden again by the clouds. Were they observatories of some ancient race, placed thus to pierce the mysteries of outer space? They would find out.

he inside of the pipe had zigzagging rings of metal, conveniently spaced for easy climbing. With Gunga leading, they soon reached the top. But not quite.

"Eh?" said Forepaugh.

"Uh?" said Gunga.

There had not been a sound, but a distinct, definite command had registered on their minds.

"Stop!"

They tried to climb higher, but could not unclasp their hands. They tried to descend, but could not lower their feet.

The light was by now relatively bright, and as by command their eyes sought the opposite wall. What they saw gave their jaded nerves an unpleasant thrill—a mass of doughy matter of a blue-green color about three feet in diameter, with something that resembled a cyst filled with transparent liquid near its center.

And this thing began to flow along the rods, much as tar flows. From the mass extended a pseudopod; touched Gunga on the arm. Instantly the arm was raw and bleeding. Terrified, immovable, he writhed in agony. The pseudopod returned to the main mass, disappearing into its interior with the strip of bloody skin.

Its attention was centered so much on the luckless Martian that its control slipped from Forepaugh. Seizing his flash pistol, he set the localized for a small area and aimed it at the thing, intent on burning it into nothingness. But again his hand was stayed. Against the utmost of his will-power his fingers opened, letting the pistol drop. The liquid in the cyst danced and bubbled. Was it laughing at him? It had read his mind—thwarted his will again.

Again a pseudopod stretched out and a strip of raw, red flesh adhered to it and was consumed. Mad rage convulsed the Earth man. Should he throw himself tooth and nail on the monster? And be engulfed?

He thought of the six-shooter. It thrilled him.

But wouldn't it make him drop that too?

flash of atavistic cunning came to him.

He began to reiterate in his mind a certain thought.

"This thing is so I can see you better—this thing is so I can see you better."

He said it over and over, with all the passion and devotion of a celibate's prayer over a uranium fountain.

"This thing is harmless—but it will make me see you better!"

Slowly he drew the six-shooter. In some occult way he knew it was watching him.

"Oh, this is harmless! This is an instrument to aid my weak eyes! It will help me realize your mastery! This will enable me to know your true greatness. This will enable me to know you as a god."

Was it complacence or suspicion that stirred the liquid in the cyst so smoothly? Was it susceptible to flattery? He sighted along the barrel.

"In another moment your great intelligence will overwhelm me," proclaimed his surface mind desperately, while the subconscious tensed the trigger. And at that the clear liquid burst into a turmoil of alarm. Too late. Forepaugh went limp, but not before he had loosed a steel-jacketed bullet that shattered the mind cyst of the pipe denizen. A horrible pain coursed through his every fibre and nerve. He was safe in the arms of Gunga, being carried to the top of the pipe to the clean dry air, and the blessed, blistering sun.

The pipe denizen was dying. A viscous, inert mass, it dropped lower and lower, lost contact at last, shattered into slime at the bottom.

iraculous sun! For a luxurious fifteen minutes they roasted there on the top of the pipe, the only solid thing in a sea of clouds as far as the eye could reach. But no! That was a circular spot against the brilliant white of the clouds, and it was rapidly coming closer. In a few minutes it resolved itself into the Comet, fast relief ship of the Terrestial, Inranian, Genidian, and Zydian Lines, Inc. With a low buzz of her repulsion motors she drew alongside. Hooks were attached and ports opened. A petty officer and a crew of roustabouts made her fast.

"What the hell's going on here?" asked the cocky little terrestial who was skipper, stepping out and surveying the castaways. "We've been looking for you ever since your directional wave failed. But come on in—come on in!"

He led the way to his stateroom, while the ship's surgeon took Gunga in charge. Closing the door carefully, he delved into the bottom of his locker and brought out a flask.

"Can't be too careful," he remarked, filling a small tumbler for himself and another for his guest. "Always apt to be some snooper to report me. But say—you're wanted in the radio room."

"Radio room nothing! When do we eat?"

"Right away, but you'd better see him. Fellow from the Interplanetary News Agency wants you to broadcast a copyrighted story. Good for about three years' salary, old boy."

"All right. I'll see him"—with a happy sigh—"just as soon as I put through a personal message."