He put down the suitcase and turned, holding the torch up so that it lighted the other side. "Come on," he said. "It's getting late."

Lil flapped across and settled down beside Horn. She looked back at Wu, who hesitated at the end of the girder.

"I'm an old man," he wailed. "I'm old and feeble. I can't do it. I've been running all day and creeping and crawling and climbing through a mountain's black heart. I can't do it. I can't stand the thought of heights. I feel dizzy already."

Horn grunted impatiently and put his foot on the end of the girder. Lil stared at Wu with her one good eye.

"Come back," Wu moaned. "Come back, my friend. I've been a sentimental fool long enough. After this you can eat coal."

"Life is more precious than diamonds," Lil said obscurely. She winked with malice. "Maybe this strong young man would like to find diamonds for me."

"You wouldn't leave me to die?" Wu gasped. "Wait. I'm coming." But his voice trembled.

He started out unsteadily, his breath coming fast and shallow. His fat arms were spread out for balance, and his eyes stared fixedly at a point in the darkness beyond Horn's shoulder. He sidled across, one foot inching forward, the other sc.r.a.ping behind.

When he was halfway across, the girder wobbled under Horn's foot. Wu stiffened, swayed, and stopped.

"Ah, no!" he said breathlessly. "Don't let it move. My poor, mistreated heart-it can't stand much more of this."

"I think," Horn said slowly, "that it's time we had a little talk."

"Of course," Wu said. "Talk, talk. Anything. I'll talk. I'm the best talker you ever heard. Only wait until I'm over there." Sweat was streaming down his face.

"I'll get better answers if you're there," Horn said calmly. "Don't move."

Wu had started to inch forward; the girder wobbled again. Wu gasped and stopped.

"What shall we talk about?" Horn asked casually. "About Sunport and why old men go there? About tunnels and valleys? About rabbits that turn into birds? About snake tracks and rabbit tracks that start suddenly and end just as abruptly? About-"

"Anything-" Wu gasped.

"What are you?" Horn asked. "And what is Lil? When I saw her the first time, her one eye was on the left. Now it's on the right."

"I'll tell you," Wu moaned. "Only let me cross. I can't talk here. I'll fall-"

"Don't move!" Horn looked down at the parrot. "Don't you try anything either, whatever you are, or your master will-"

But as Horn looked down, the girder twisted under his foot. Wu screamed and tottered, his arms contorting themselves grotesquely.

Before Horn could move, the old man had toppled into the black pit.

THE HISTORY.

Port of the sun. Sunport....

It rose from its own ashes, phoenixlike, and launched its gleaming, wingless children toward the stars. Outward they spread in a vast sphere, seeking the new worlds, the virgin worlds, carrying with them a spark of the immortal flame. Where they landed, the spark leaped and grew.

Sunport waited, but they did not come back.

They found all kinds of worlds: some so sweet they could not leave, some so bitter there was no time for anything but struggle.... They relaxed, or they fought. They shaped and were shaped.

Weary, like Earth, Sunport waited. Exhausted, like the soil and the mines, Sunport waited. Still waiting, Sunport returned to ashes.

And at last they came. They came as conquerors. But they were still the children of Earth. Changed a little, they were still men.

Something stirred in the ashes....

4.

PHOENIX.

While Wu was still toppling, something whirred beside Horn and disappeared swiftly into the darkness. Horn glanced quickly around. They were both gone, Wu and Lil. Horn listened. The seconds pa.s.sed, and there was no distant splash from the pit.

Horn put one foot on the girder and held up the torch. The fat old man was dangling under the girder, his mouth opening and shutting in mute terror, his arms and legs pushing downward as if they could shove the blackness away.

A wire gleamed. It circled the rusty beam. A bright metal hook went through the waistband of Wu's baggy breeches. Where the wire joined the hook was blue brilliance, burning in the torchlight with a cold, splendid luminescence. It was faceted, like diamonds, thousands of them sparkling....

Kicking, gasping, Wu swung jerkily back and forth. Horn shook himself. He walked out on the beam, stooped, took hold of the unexplainable wire. It moved liquidly in his hand, and he almost dropped it and the living burden it supported. His hand tightened. Inside it was a comfortable handle.

He backed along the girder, his chest rigid with strain, shining with sweat. Wu swung heavily below, each swing threatening to send them both into the gulf. Finally one backward-reaching foot touched solid rock. Horn strained backward. Wu swung in, rising. His hands caught the edge of rock. He clawed his way desperately over the brink, crawled meters from the edge, and collapsed, panting and trembling.

The thing in Horn's hand flowed again. Horn looked down. The parrot was perched on his finger, her ragged wings drooping wearily.

"Disaster," she said breathlessly, "is the crucible of human hearts. We thank you, my master and I."

Wu sat up slowly. "Indeed, indeed. You are a n.o.ble young man, brave-"

"It won't go away if you shut your eyes," Horn said.

He stuck the torch into a crevice in the wall. It flared smokily over the scene as he sat down and pulled his gun forward between his knees so that it pointed toward the old man and the bird perched now on his shoulder.

"I toppled you off the girder," Horn said. "I'd just as soon toss you over the edge again."

"It was a stupid thing to do," Wu said. "You can't get answers from a dead man."

"Obviously. What is your life worth to you? It's immaterial to me whether you live or die."

Wu sighed and shook his head. "Ah, violence! You give us no choice. An old man and an old bird, what chance do we have against youth and callousness and a gun?"

"Answers," Horn said.

"How old do you think I am?" Wu asked.

Horn stared at Wu's ageless face. "Seventy? Eighty?" he said, and knew that he was wrong.

"More than fifteen hundred. Fifteen hundred weary years. Searching for peace and never finding it. Longing for rest and afraid of dying. Lil and I going on and on."

Horn's eyes narrowed, but the rest of his face was immobile.

"Like Lil, I am the last of my race," Wu went on. "When I was born on Stockton Street in San Francisco, my people were the most numerous on Earth. And the oldest. But they clung to Earth while others went out to the stars. With Earth, they died.

"I was different. I immigrated to Mars. At Syrtis City, with youthful folly, I established the New Canton Sanitary Laundry. But water was scarce and cleaning fluids were dear. It was cheaper to weave new plastic clothes than to clean them.

"I became a ship's cook on a small, prospecting vessel. Its owners struck the richest treasure in history. On one of the asteroids, we found the Diamond Cavern."

Wu crawled warily to the suitcase close to the edge of the pit, dug into it, and crawled back with a bottle. He lifted it to his lips; his throat moved convulsively twice before he lowered it and handed it to Lil. Wu sighed; his small, black eyes blinked.

"Living diamonds, sir. Carbon deposits in a mountain torn from an exploding world. The cavern was underlaid by uranium. For a long time, that energy fed Lil's race; when it began to fail, they learned how to fission individual atoms. When the uranium was used up entirely, they learned to gather thermal energy even from very cold molecules, in defiance of the Second Law of Thermodynamics. Improbable? True. But all life exists in a kind of defiance of the Second Law.

"Living diamonds. But the creatures were more wonderful than their crystalline skins. As you have noticed, Lil is no parrot. She is a pseudomorph of the Diamond Cavern."

A tear sparkled gemlike in Lil's one eye and dropped to the dusty tunnel floor.

"Lil's race had many things to offer men. They had a culture almost as old as Earth itself. Energy was low there; time moved slowly. They were almost immortal. But the ship's crew saw only one thing: the diamonds. One radiation bomb destroyed the cavern and all the creatures in it, discoloring and ruining most of the diamonds in the process. Only Lil was saved. I hid her in the galley. We have been together ever since."

Lil moaned thinly. "Poor old Lil," she sobbed. "She's all alone. Ah, ah, ah. Her people, all gone. Her world murdered and forgotten. No friend in all the universe but poor old Wu. Oh, the lost wonder, the beauty...."

She wilted. Horn's gun lifted. Wu held up a warning finger. "Sh-h-h," he said softly. "You are going to see something that no one alive but me has ever seen."

Lil's gay, disheveled plumage flowed. The yellow legs collapsed into pliant pseudopods. A glittering surface of diamond was uncovered. Everything else ran shapelessly into an opening at the top, leaving a diamond the size of a man's two hands clasped together.

Torchlight struck it. The diamond threw it back, multiplied, in an incredible glory of prismatic colors. Horn caught his breath.

"Wait," Wu whispered. "Wait until she opens."

Seams appeared in the top of the burning, thousand-faceted spheroid. Six diamond petals bent slowly down. Above them rose six slender, living tendrils. Reaching pink fingers, they grew and divided into delicate and intricate membranes like a pure white web.

"With those and her amorphous body," Wu said, "she can a.s.sume any form she wishes. Those tracks you saw, the rabbit who looked at you across the stream, the bird that flew to me-all Lil."

The pistol slipped from Horn's relaxed hand; it slithered up under his shoulder. At the sound, the diamond thing leaped explosively into the air. Its splendor was concealed, in an instant, by the parrot's ragged feathers.

Lil swayed and moaned again. "Gone, all gone."

"Don't cry, Lil," Wu said softly. He rummaged deep in one pocket. "Here's a little trinket I've been saving for a bitter hour. It came out of the stickpin of a grafting Company inspector who tried to jail us for vagrancy."

Lil stopped moaning and flapped to Wu's shoulder. Her strong beak took the gleaming, pea-sized diamond delicately from his thick fingers. A m.u.f.fled crunch and the stone was gone.

"One tomorrow," she said cheerfully, "is worth a million yesterdays." She rubbed her beak affectionately against Wu's wrinkled cheek. "A most beautiful diamond."

"She can a.s.similate almost any form of carbon," Wu said. "But she prefers diamond. When we're prosperous, that's what she eats. Recently we've been reduced to anthracite."

"The secret," Horn said coldly. "How have you lived so long?"

"Lil," Wu said. "Her people learned many things in their long, almost eternal existence: life, probability, atomic structure.... That was only one of the things mankind lost through greed. She keeps me alive, and I help her find food.

"We wander. If we stay still very long, Duchane's Index will find us. That vast collection of memory would quickly fit our descriptions into a thousand-year-old record of jewel thefts. We would like to stay on the frontiers, beyond the reach of Eron, but there are few diamonds there.

"Wanderers, eternal vagabonds, we have seen a hundred worlds and known them all and have only our memories that go back too far to show for it. We must keep moving. Men would wonder why I don't die. My secret would rouse in them the same madness as Lil's diamond carapace. They would kill me for it.

"Yet there are consolations. There is always tomorrow-a new ship to catch, a virgin planet waiting. When memory grows too long, there's a way to blot it out. The weed for me, and diamonds for Lil, and rum for both of us."

Horn studied them for a moment. "That's all you've done with it?"

Wu shrugged. "What would you do?"

"It would give a man a different perspective," Horn said thoughtfully. "You could do something for all humanity: in science, politics, philosophy. You owe it-"

"For what?" Wu asked dryly. "Humanity had nothing to do with it. It tossed away its chance when its representatives wiped out Lil's race."

"Original sin?" A smile flickered across Horn's face. "If a man could think things out thoroughly, plan carefully, act slowly," he mused, "he could guide his people into better, wiser paths. If a tyrant arose, like Eron, he could-"

"One man against an empire?" Wu broke in. "Empires rise and fall, and that cycle is dictated by forces ignorant of things as insignificant as a man. They are as vast and mysterious in their workings as fate itself. Eron will fall-in its own time. But you will probably be long dead, and I myself may be dead. Even Lil can't push that finality away forever."

"Forces!" Horn shrugged. "They are only men in the ma.s.s. One man can lead them or push them. And one man, acting at the right time, at the right place, in the right way, can topple the greatest boulder."

"And get crushed himself when it falls," Wu said. "No, thank you. As long as I have lived, as weary as life sometimes grows, I cling to it-more desperately even than you. What have you to lose but a few unhappy years? It is easy for you to be foolhardy and contemptuous of danger. I must be timid and cowardly. This miserable carca.s.s, which has lasted me so long, may last me as long again, with care."

Horn was on his feet. He pulled the torch out of the wall and motioned with his head for Wu and Lil to go in front. Wu picked up his suitcase and turned his head back to look at Horn.

"Don't you believe me, sir?"

"You aren't in the pit, are you?" Horn answered. The question Wu asked was something Horn couldn't answer directly. For the moment he was willing to accept it as a working hypothesis; it fitted the observed data. In addition, it was too fantastic not to have an element of truth. "Keep moving. We may be late as it is."

"We mustn't make you late for your appointment with destiny," Wu said. The words floated back mockingly.

The tunnel began to widen. It spilled them into a great chain of vast black areas: warehouses, Horn guessed, for the first interplanetary commerce. Sloping ramps led them up and up again. With the first distant suggestion of sunlight, Horn ground out the torch against the wall and, a little farther on, leaned it against the side of the last broad tunnel.

Storms had washed mud and debris into the crumbling entrance. The narrow exit that remained was well concealed by a gnarled juniper tree. Horn peered between the leaves. Beyond were ruins: mounds of weathered rubble pierced by an occasional rusted spear, a tottering wall. It was deserted. Horn climbed through the hole and slipped down under the lowest branch. Wu followed with a m.u.f.fled sigh of relief.

Horn crept to the shaky wall and glanced quickly over it. He stifled an exclamation. "The Victory Monument!"

It towered against the noon sky, eight hundred meters away, where once the Mars Docks of Old Sunport had been. But even Sunport, at her proudest, couldn't have built this.

Its base was an immense black cube capped with a black hemisphere. It was at least nine hundred meters high. Towering endlessly above that rounded pedestal was a great, cylindrical column. It was faced with luxion and glowed with rising waves of living color. Blood-red just above the black hemisphere, it shimmered through orange, yellow, green, blue, indigo, and violet. The top faded to a shining white.

Crowning the pillar, four kilometers overhead, was a huge, steel-gray sphere, smooth and featureless except at the poles. There, thousands of slender golden spikes bristled in every direction.

"Eron!" Wu said at Horn's elbow.

"I've never seen it," Horn said.

"It's a good reproduction," Wu said. "That's it. Eron. Your boulder. Let's see you topple it."