One hundred feet: a mighty bulge slimed over the ground, four times the height of a man, quivering jellylike as though it sensed its prey. Progenitor's bony body echoed that movement in sympathetic vibration. Mat's gorge rose, fouling his throat as he fought for control over his emotions. He had captured Phoebus in the stone, bringing him far across the plain, winging from surface to surface; but would this tiny spark from the sun's domain daunt Phog?
Seventy-five feet: Terror lashed his mind, convulsed his muscles; muscles hard from the hauling of great slabs. "Now! Now!" the old man shouted, his voice a high-pitched wail. Mat gulped, shaking from head to knee, but held himself from action. He yearned to yank the curtain away—the curtain that held back the fierce sunlight chained in this final relay; but for the sake of the test he dared not unveil this light too soon.
Fifty feet: The impalpable stuff of Phog bubbled and swirled, exhaling digestive vapors. Mat's eyes smarted; his nostrils pinched together in vain attempt to filter out the alien gas. Behind him, Progenitor coughed and racked, unable to call again.
Mat's hands gripped the warm stone spasmodically—and did not act. Suppose, somehow, Phoebus had lost his strength; suppose the light only angered the monster....
Twenty-five feet: Phog loomed, as tall as the distance between them, curling up into a deadly hood. Phoebus was far far away, beyond help—except for the caged beam. Somewhere inside the awful shroud, uncaged, the insatiable Runner slavered. If the weapon failed—
Mat acted. Hands now fumblingly eager lifted free the fiber shield. Suddenly there was a brightness; a coruscating beam stabbed out and struck the ground ahead. It was a ray of the sun, blinding in the gloom, harnessed by tireless labor during Mat's last foot of growth.
He took hold of the balanced stone, tilting it up. The beam followed, reflecting from the polished surface and marching along the ground, up and into Phog itself. Now—
Phog sizzled and folded into itself, trying to escape that burning light. But the darting lance played over its surface, vaporizing the rank mists wherever it touched.
To one side and the other Phog continued its advance; but before that implacable shaft it retreated, wounded, dribbling dismal white droplets. It was unable to attack.
"It works!" Progenitor cried. "We have defeated Phog!"
Mat answered him with a smile, allowing the old man his share of pride. Victory was sweet indeed.
The light failed.
Phog rolled back, facelessly gloating. Feverishly Mat cast about, seeking the malfunction, but there was none. The reflectors were in order, yet the beam was not coming in.
He looked up to see Phog fifteen feet distant, offering a putrescent embrace. Within it—were there malevolent eyes?
The beam snapped on. Phog recoiled furiously. Had the phantom shape within been singed? He kept the light fixed on one spot, drilling a hole in the wall before him, while his mind pondered the meaning of that brief cessation. Would it happen again?
The malodorous veil crept up around the beam, leaving a harmless tunnel. Phog was accommodating itself. Quickly he switched the light to another place.
The glow died. Phog sucked together and reached for him. Fifteen feet....
"Someone is cutting off the relay!" Progenitor cried.
Of course! The tribesmen knew nothing of the careful mechanisms spanning the plain. They would be out searching for food, wandering carelessly between the pylons, intercepting the invisible channel of light.
Anger flushed Mat's face. He had held Phog at bay, had tasted victory over the killer of men—only to be defeated by other people's ignorance. The beam flicked on and off again, as though to flaunt his impotence, and Phog crept up to a hungry ten feet.
"We must go," he called, forgetting the deference due his ancestor. But at the lip of Phog there was no time to stand on ceremony. They ran.
The banks of solid mist were far beyond their position. They were at the nadir of a deep cleft, carved by the light. Phog threatened momentarily to fill in from the sides, capturing them. Even as he ran, Mat made a mental note to provide for the protection of his flank, perhaps with additional relays, if he escaped this time.
Progenitor was puffing hugely, blowing out his white whiskers as he ran. Mat saw that the oldster could not maintain the pace for long. Yet there was no effective or honorable way to assist him; he was the grandfather. If only the beam were reliable, they could make a stand—
Phoebus returned, overhead, and suddenly they were safe. What determined the comings and goings of the high wisps that shrouded it and let Phog come? He would have to study this—
Progenitor collapsed by a relay, exhausted. In the distance Mat observed the tribesmen returning, meandering along the line of relays. Rage blotted his sight for an instant; then he began to think.
When the people arrived there was a pile of stones beside the pylon, buttressing the path of the beam but not interfering with it. "Cross here," Mat told the incurious people. "Climb up the rocks, so; then jump over to the other side and step down."
They looked at him and at the steps transcending empty sand, uncomprehending. "Phoebus is here," he explained. "We must keep it safe, to battle Phog." But he saw that he was making no impression. They knew nothing about his beam of light, or the principles of reflection he had devised to control it. They had no interest in anything except hunger and immediate danger and occasional ancestry of infants. Not one of them would consider standing up to the awesome enemy. Docile and timid, they had abdicated the courage and intelligence of Man. Progenitor had warned him of this.
Mat picked up a ragged stone. "If anyone fails to use the steps," he said, "I will smash this against his head."
The nearest man looked at him. The man was larger than he and older. Mat's bravado deserted him. He did not want to fight; he longed to drop his weapon and flee—as he had from Phog. He was one of the Tribe; he had no courage. If the man crossed the beam....
A girl was watching him, one he had not noticed before. Something about her bothered him; she seemed familiar. Then it came to him; she was the age his sister would have been.
Shame overcame his dread. The ghost of Sal mocked him in this girl's eyes. Not again would his cowardice sacrifice her body to the Runner. Not again would the bloodless bones rise to haunt his memory.
Mat hefted the stone with new purpose. He pointed to the crude stile surmounting the path of the beam. Apprehensively, the man obeyed.
After that, so did the others. It was plain that they did not understand the ritual of treading over nothing; but they gave way to his greater determination. They did the easy thing; they backed down in the face of a threat, as always.
Never again would he be like them.
Last to navigate the stile was the girl. "You're so brave," she said, smiling at him. "My name is Jul."
Three relays marched across the land to converge upon the battlefield of shining stones. The plain was pocked with the marks of their excavation, for the rocky formation had tilted deep into the earth, as though to hide its splendor. Many tribesmen had labored under Mat's direction to bring up the flat slabs and cleave them apart to reveal the brightness inside; many fingers of growth had passed while they rubbed and rubbed to accentuate that shine with fine fibers and make the surfaces ready for Phoebus.
Two mighty structures stood at the terminus, each as high as a man could reach. Each comprised two columns bearing a great stone crosspiece, and the two arches faced each other to form a two-sided cube visible for many thousands of feet. Each column was fashioned from highly glossed stones tilted this way and that, and above the crosspieces were perched more polished fragments.