Just as the sun fell below the rim of the asteroid, plunging it into a darkness only faintly relieved by the light of the stars, he crashed into the deeper underbrush. A trailing creeper tripped him in his mad flight. He fell headlong, to lie panting, sobbing for breath, in the thick carpet of blood-colored moss.

Behind him, from the direction of the lake, he heard a sudden clangor as of rock beating against metal. This endured only a short time. Then the solid ground beneath him shook slightly, and an appalling crash of trees and underbrush to the rear told him that the stone colossus was on his trail.

He leaped to his feet and continued his great bounds over the sharply curved surface of the asteroid, banging against tree trunks, bruising himself against stones, falling in the darkness to rise again and flee as before in a mad attempt to distance the crashing sound of pursuit behind him.

Then he felt himself writhing in thin air as his flying course took him over the edge of a cliff. Down, down he fell, to land in a dense bed of foliage far below. Something hit his head with terrific force. Pinwheels of light flashed before his eyes, to fade into velvety nothingness....

Slowly, uncertainly he wavered back to consciousness. For a moment he was aware of nothing save that he was lying on some surface that was jagged and uncomfortable, and that it was broad daylight. He opened his eyes, and saw that he was reclining, across a springy bed formed of the top of a tree. Ahead of him loomed a cliff about a hundred feet high.

Remembrance suddenly came to him. The unreasoning rush through the underbrush. The nightmare creature lumbering swiftly after him. The fall over the cliff into the top of this tree.

With a cry, he sat up, expecting to see the stone giant nearby and poised to leap. But it was nowhere in sight; nor, listen as intently as he would, could he hear the sounds of its crashing path through the brush. Somehow, for the moment at least, he had been saved. Perhaps his disappearance over the cliff edge had thrown it off his track.

He became aware of the fact that it was difficult for him to breathe.

His lungs were heaving in a vain effort to suck in more oxygen, and his tongue felt thick as though he were being strangled. Then he saw that his oxygen concentrator had been knocked from his head when he fell, and was dangling from a limb several feet away. It was almost out of breathing range. Had it fallen on through the branches to the ground he would have died, in his unconsciousness, in the rarified atmosphere. He reached for it; settled the band around his head again.

After once more listening and peering around to make sure the rock colossus was not about, he descended the tree that had saved his life, and began to walk in the direction he judged the lake to be. He would get into his Dart, cruise aloft out of harm's way, and perhaps think up some effective course of action.

He was thinking clearly, now. And, in the glare of daylight, no longer an unreasoning animal fleeing blindly over a dim-lit foreign sphere, he was unable to understand his panic of the night. Afraid? Of course he had been afraid! What man wouldn't have been at sight of that monstrous thing? But that he, Harley 2Q14N20, should have lost his head completely and gone plunging off into the brush like that, seemed unbelievable. To the depths of his soul he felt ashamed. And to his own soul he made the promise that he would wipe out, in action, that hour of cowardice.

As he wound his way through the squat, carmine forest, he tried to figure out the nature of the thing that had crashed balefully after him in the black hours.

It had seemed made of rock--a giant, primitive stone statue imbued with life. But it was impossible that it should really be fashioned of rock.

At least it ought to be impossible. Rock is inorganic, inanimate. It simply couldn't have the spark of life in it. Harley had seen many strange creations, on many strange planets, but never had he seen inorganic mineral matter endowed with animation. Nor had anyone else.

Yet the thing _looked_ as though made of stone. Of some peculiar, quartz-suffused granite--proving that the wan, white-haired man he had talked to in the sanitarium had not been mad at all, but only too terribly sane. The creature's very eyes had had a stony look. Its eyelids had rasped like stone curtains rubbing together. Its awful, two-fingered hands, or claws, had ground together like stones rubbing.

Was it akin to the lizards, the cold-blooded life of Earth? Was this rocky exterior merely a h.o.r.n.y sh.e.l.l like that of a turtle? No. Horn is horn and rock is rock. The two can't be confused.

The only theory Harley could form was that the great beast was in some strange way a link between the animal and the mineral kingdoms. Its skeletal structure, perhaps, was silicate in substance, extending to provide an outside covering that had hardened into actual stone, while forming an interior support to flesh that was half organic, half inorganic matter. Some such silicate construction was to be found in the sponge, of Earth. Could this be a gigantic relative of that lowly creature? He did not know, and couldn't guess. He wasn't a zoologist.

All he knew was that the thing appeared to be formed of living, impregnable stone. He knew, also, that this fabulous creature was bent on destroying him.

At this point in his reflections, the glint of water came to his eyes between the tree trunks ahead of him. He had come back to the lake.

For moments he stood behind one of the larger trees on the fringe and searched around the sh.o.r.e for sight of the rock giant. It was nowhere in evidence. Rapidly he advanced from the forest and ran for the Dart. From a distance it appeared to be all right: but as he drew near a cry rose involuntarily to his lips.

In a dozen places the double hull of the little s.p.a.ce craft was battered in. The man-hole lid was torn from its braces and bent double. The gla.s.s panels, unbreakable in themselves, had been shoved clear into the cabin; their empty sash frames gaped at Harley like blinded eyes. Never again would that Blinco Dart speed through the heavens!

He went to the spot where he had left his Sco drill, and a further evidence of the thing's cold blooded ferocity was revealed. The intricate mechanism had been wrenched into twisted pieces. The drums were battered in and the flexible hose lengths torn apart in shreds. The inventor himself couldn't have put it in working order again.

He was hopelessly trapped. He had no means of fighting the colossus. He had no way of escaping into s.p.a.ce, nor of returning to Earth and trying to raise a loan that would allow him to come back here with men and atomic guns. He hadn't even a way of intrenching himself in the ground against the next attack.

For an instant his hair p.r.i.c.kled in a flash of the blind panic that had seized him a few hours before. With a tremendous effort of will he fought it down. This--the destruction of his precious Dart and drill--was the result of one siege of insensate fear. If he succ.u.mbed to another one he might well dash straight into the arms of death. He sank to the ground and rested his chin on his fist, concentrating all his intellect on the hopeless problem that faced him.

The surface of Z-40 was many square miles in extent. But, if he tried to hide himself, he knew it was only a question of time before he would be hunted down. The asteroid was too tiny to give him indefinite concealment. Flight, then, was futile.

But if he didn't try to conceal himself in the spa.r.s.e forest lands, it meant that he must stay to face the monster at once--which was insanity.

What could he do, bare-handed, against that thirty-foot, three-tentacled, silicate ma.s.s of incredible life!

It was useless to run, and it was madness to stay and confront the thing. What, then, could he do? The sun had slid down the sky and the red of another swift dusk was heralding the short night before he shook his head somberly and gave the fatal riddle up.

He rose to his feet, intending to make his way back to the concealment--such as it was--of the forest. It might be that he could find safety in some lofty treetop till day dawned again. Then he stopped, and listened. What was that?

From far away to the left he could hear faint sounds of some gargantuan stirring. And, coincident with the flickering out of the last sc.r.a.p of sunlight, a distant crashing came to his ears as an enormous body smashed like an armored ship through trees and thorn bushes and trailing vines. The rock thing had found his trail and was after him again.

A second time Harley fled through the dim-lighted night, stumbling over boulders and tripping on creepers. But this time his flight was not that of panic. Frightened enough, he was; but his mind was working clearly as he leaped through the forest away from the source of the crashing.

The first thing he noted was that though--as far as his ears could inform him--he was managing to keep his lead, he wasn't outdistancing his horrible pursuer by a yard. Dark though the night was, and far away as he contrived to keep himself, the colossus seemed to cling to his trail as easily as though following a well-blazed path.

He climbed a tree, faced at right angles to the course he had pursued, and swung for the next tree. It was a long jump. But desperation lent abnormal power to his muscles, and the gravity regulator adjusted to extremely low pitch, was a great help. He made it safely. Another swinging leap into the dark, to land sprawling in a second tree; a third; a fourth. Finally be crouched in a tangle of boughs, and listened. He was a quarter of a mile from the point where he had turned from his first direction. Perhaps this deviation would throw the rock terror off.

It didn't. He heard the steady smashing noise stop. For an instant there was a silence in the darkness of the asteroid that was painful. Then the crashing was resumed, this time drawing straight toward where he was hidden. Somehow the thing had learned of his change of direction.

He continued his flight into the night, his eyes staring gla.s.sily into the darkness, his expression the ghastly one of a condemned man. And as he fled the crashing behind him told how he was followed--easily infallibly, in spite of all his twisting and turning and efforts at concealment. What h.e.l.lish intelligence the monster must possess!

He ran for eternities. He ran till his chest was on fire, and the sobbing agony of his breathing could be heard for yards. He ran till spots of fire floated before his eyes and the blood, throbbing in his brain, cut out the noise of the devilish pursuit behind him. At long last his legs buckled under him, and he fell, to rise no more.

He was done. He knew it. His was the position of the hunted animal that lies panting, every muscle paralyzed with absolute exhaustion, and glares in an agony of helplessness at the hunter whose approach spells death.

The crashing grew louder. The tremor of the ground grew more p.r.o.nounced as the vast pursuer pounded along with its tons and tons of weight.

Harley gazed into the blackness back along the way he had come, his eyes sunk deep in the hollows fatigue had carved in his face, and waited for the end. The dark night darkened still more with the approach of another swift, inexorable dawn.

There was a terrific rending of tree trunks and webbed creepers. Dimly in the darkness he could see something that towered on a level with the tallest trees, something that moved as rapidly and steadily as though driven by machinery. Fear so great that it nauseated him, swept over him in waves; but he could not move.

The first grey smear of dawn appeared in the sky. In the ghostly greyness he got a clearer and clearer sight of the monster. He groaned and cowered there while it approached him--more slowly now, eyeing him with staring, stony orbs in which there was no expression of any kind, of rage or bate, of curiosity or triumph.

Great stumps of legs, with no joints in them, on which the colossus stalked like a moving stone tower--a body resembling an enormous boulder carved by an amateurish hand to portray the trunk of a human being--a craggy sphere of rock for a head, set directly atop the deeply riven shoulders--a face like the horrible mask of an embryonic gargoyle--a mouth that was simply a lipless chasm that opened and closed with the sound of rocks grinding together in a slow-moving glacier--the whole veiled thinly by trailing lengths of snapped vines, great shattered tree boughs, bushes, all uprooted in its stumping march through the forest!

Harley closed his eyes to shut out the sight. But in spite of himself they flashed open again and stared on, as though hypnotized by the spectacle they witnessed.

The grey of dawn lightened to the first rose tint of the rising sun. As though stung to action by the breaking of day, the thing hastened its ground-shaking pace. With one last stride, it came to Harley's side and loomed far above, the unwinking eyes glaring down at him.

The three arms, hinged at equidistant points at the base of the horrible head, slowly lowered toward his prostrate form. There was a grating noise as the creature hinged in the middle and bent low, bringing its enormous, staring eyes within two yards of his face.

One of its hands closed over his leg, tentatively, experimentally, as though to ascertain of what substance he was made. He cried aloud as the rock vise, like a gigantic lobster claw, squeezed tight. The thing drew back abruptly. Then the chasm of its mouth opened a little, for all the world as though giving vent to soundless, demoniac laughter. All three of the vise-like hands clamped over him--lightly enough, considering their vast size, and intimating that the colossus did not mean to kill him for a moment or two--but so cruelly that his senses swam with the pain of it.

He felt the grip relax. The vast stone pincers were lifted from him; slithered to the ground beside him.