Never hesitating, the machine raced on along the path he had so carefully mapped out for it. A part of him was still pleading angrily to be released, but he knew now that he was safe. And presently Seranis understood that too, for the forces inside his brain ceased to war with one another. Once more he was at peace, as ages ago an earlier wanderer had been when, lashed to the mast of his ship, he had heard the song of the Sirens die away across the wine-dark sea.

  10.

  "So you see," concluded Alvin, "it will carry out any orders I give, no matter how complicated they are. But as soon as I ask questions about its origin, it simply freezes like that."

  The machine was hanging motionless above the Master Associa-tor, its crystal lenses glittering in the silver light like a cluster of jewels. Of all the robots which Rorden had ever met, this was by far the most baffling: he was now almost sure that it had been built by no human civilization. With such eternal servants it was not surprising that the Master's personality had survived the ages.

  Alvin's return had raised so many problems that Rorden was almost afraid to think of them. He himself had not found it easy to accept the existence of Lys, with all its implications, and he wondered how Diaspar would react to the new knowledge. Probably the city's immense inertia would cushion the shock: it might well be years before all of its inhabitants fully appreciated the fact that they were no longer alone on Earth.

  But if Alvin had his way, things would move much more quickly than that. There were times when Rorden regretted the failure of Seranis' plans—everything would have been so much simpler. The problem was immense, and for the second occasion in his life Rorden could not decide what course of action was correct. He wondered how many more times Alvin would present him with such dilemmas, and smiled a little wryly at the thought. For it would make no difference either way: Alvin would do exactly as he pleased.

  As yet, not more than a dozen people outside Alvin's own family knew the truth. His parents, with whom he now had so little in common and often did not see for weeks, still seemed to think that he had merely been to some outlying part of the city. Jeserac had been the only person to react strongly: once the initial shock had worn off he had engaged in a violent quarrel with Rorden, and the two were no longer on speaking terms. Alvin, who had seen this coming for some time, could guess the details but to his disappointment neither of the protagonists would talk about the matter.

  Later, there would be time enough to see that Diaspar realized the truth: for the moment Alvin was too interested in the robot to worry about much else. He felt, and his belief was now shared by Rorden, that the tale he had heard in Shalmirane was only a fragment of some far greater story. At first Rorden had been skeptical, and he still believed the "Great Ones" to be no more than another of the world's countless religious myths. Only the robot knew the truth, and it had defied a million centuries of questioning as it was defying them now.

  "The trouble is," said Rorden, "that there are no longer any engineers left in the world."

  Alvin looked puzzled: although contact with the Keeper of the Records had greatly enlarged his vocabulary, there were thousands of archaic words he did not understand.

  "An engineer," explained Rorden, "was a man who designed and built machines. It's impossible for us to imagine an age without robots—but every machine in the world had to be invented at one time or other, and until the Master Robots were built they needed men to look after them. Once the machines could care for themselves, human engineers were no longer required. I think that's a fairly accurate account, though of course it's mostly guesswork. Every machine we possess existed at the beginning of our history, and many had disappeared long before it started."

  "Such as flyers and spaceships," interjected Alvin.

  "Yes," agreed Rorden, "as well as the great communicators that could reach the stars. All these things vanished when they were no longer needed."

  Alvin shook his head.

  "I still believe," he said, "that the disappearance of the spaceships can't be explained as easily as that. But to get back to the machine— do you think that the Master Robots could help us? I've never seen one, of course, and don't know much about them."

  "Help us? In what way?"

  "I'm not quite sure," said Alvin vaguely. "Perhaps they could force it to obey all my orders. They repair robots, don't they? I suppose that would be a kind of repair. . . ."

  His voice faded away as if he had failed even to convince himself.

  Rorden smiled: the idea was too ingenuous for him to put much faith in it. However, this piece of historical research was the first of all Alvin's schemes for which he himself could share much enthusiasm, and he could think of no better plan at the moment.

  He walked toward the Associator, above which the robot was still floating as if in studied indifference. As he began, almost automatically, to set up his questions on the great keyboard, he was suddenly struck by a thought so incongruous that he burst out laughing.

  Alvin looked at his friend in surprise as Rorden turned toward him.

  "Alvin," he said between chuckles, "I'm afraid we still have a lot to learn about machines." He laid his hand on the robot's smooth metal body. "They don't share many human feelings, you know. It wasn't really necessary for us to do all our plotting in whispers."

  11

  This world, Alvin knew, had not been made for Man. Under the glare of the trichromatic lights—so dazzling that they pained the eyes—the long, broad corridors seemed to stretch to infinity. Down these great passageways all the robots of Diaspar must come at the end of their patient lives, yet not once in a million years had they echoed to the sound of human feet.

  It had not been difficult to locate the maps of the underground city, the city of machines without which Diaspar could not exist. A few hundred yards ahead the corridor would open into a circular chamber more than a mile across, its roof supported by great columns that must also bear the unimaginable weight of Power Center. Here, if the maps spoke the truth, the Master Robots, greatest of all machines, kept watch over Diaspar.

  The chamber was there, and it was even vaster than Alvin had imagined—but where were the machines? He paused in wonder at the tremendous but meaningless panorama beneath him. The corridor ended high in the wall of the chamber—surely the largest cavity ever built by man—and on either side long ramps swept down to the distant floor. Covering the whole of that brilliantly lit expanse were hundreds of great white structures, so unexpected that for a moment Alvin thought he must be looking down upon a subterranean city. The impression was startlingly vivid and it was one he never wholly lost. Nowhere at all was the sight he had expected— the familiar gleam of metal which since the beginning of time Man had learned to associate with his servants.

  Here was the end of an evolution almost as long as Man's. Its beginning was lost in the mists of the Dawn Ages, when humanity had first learned the use of power and sent its noisy engines clanking about the world. Steam, water, wind—all had been harnessed for a little while and then abandoned. For centuries the energy of matter had run the world until it too had been superseded, and with each change the old machines were forgotten and the new ones took their place. Very slowly, over millions of years, the ideal of the perfect machine was approached—that ideal which had once been a dream, then a distant prospect, and at last reality:

  No machine may contain any moving parts.

  Here was the ultimate expression of that ideal. Its achievement had taken Man perhaps a thousand million years, and in the hour of his triumph he had turned his back upon the machine forever.

  The robot they were seeking was not as large as many of its companions, but Alvin and Rorden felt dwarfed when they stood beneath it. The five tiers with their sweeping horizontal lines gave the impression of some crouching beast, and looking from it to his own robot Alvin thought it strange that the same word should be used for both.

  Almost three feet from the ground a wide transparent panel ran the whole length of the
structure. Alvin pressed his forehead against the smooth, curiously warm material and peered into the machine. At first he saw nothing: then, by shielding his eyes, he could distinguish thousands of faint points of light hanging in nothingness. They were ranged one beyond the other in a three-dimensional lattice, as strange and as meaningless to him as the stars must have been to ancient Man.

  Rorden had joined him and together they stared into the brooding monster. Though they watched for many minutes, the colored lights never moved from their places and their brilliance never changed. Presently Alvin broke away from the machine and turned to his friend.

  "What are they?" he asked in perplexity.

  "If we could look into our own minds," said Rorden, "they would mean as little to us. The robots seem motionless because we cannot see their thoughts."

  For the first time Alvin looked at the long avenue of titans with some trace of understanding. All his life he had accepted without question the miracle of the synthesizers, the machines which age after age produced in an unending stream all that the city needed. Thousands of times he had watched that act of creation, never thinking that somewhere must exist the prototype of that which he had seen come into the world.

  As a human mind may dwell for a little while upon a single thought, so these greater brains could grasp and hold forever the most intricate ideas. The patterns of all created things were frozen in these eternal minds, needing only the touch of a human will to make them reality.

  The world had gone very far since, hour upon hour, the first cavemen had patiently chipped their arrowheads and knives from the stubborn stone.

  "Our problem now," said Rorden, "is to get into touch with the creature. It can never have any direct knowledge of Man, for there's no way in which we can affect its consciousness. If my information's correct, there must be an interpreting machine somewhere. That was a type of robot that could convert human instructions into commands that the Master Robots could understand. They were pure intelligence with little memory—just as this is a tremendous memory with relatively little intelligence."

  Alvin considered for a moment. Then he pointed to his own robot.

  "Why not use it?" he suggested. "Robots have very literal minds. It won't refuse to pass on our instructions, for I doubt if the Master ever thought of this situation."

  Rorden laughed.

  "I don't suppose he did, but since there's a machine specially built for the job I think it would be best to use it."

  The Interpreter was a very small affair, a horseshoe-shaped construction built around a vision screen which lit up as they approached. Of all the machines in this great cavern, it was the only one which had shown any cognizance of Man, and its greeting seemed a little contemptuous. For on the screen appeared the words:

  STATE YOUR PROBLEM PLEASE THINK CLEARLY

  Ignoring the implied insult, Alvin began his story. Though he had communicated with robots by speech or thought on countless occasions, he felt now that he was addressing something more than a machine. Lifeless though this creature was, it possessed an intelligence that might be greater than his own. It was a strange thought, but it did not depress him unduly—for of what use was intelligence alone?

  His words died away and the silence of that overpowering place crowded back upon them. For a moment the screen was filled with swirling mist, then the haze cleared and the machine replied:

  REPAIR IMPOSSIBLE ROBOT UNKNOWN TYPE

  Alvin turned to his friend with a gesture of disappointment, but even as he did so the lettering changed and a second message appeared:

  DUPLICATION COMPLETED PLEASE CHECK AND SIGN

  Simultaneously a red light began to flash above a horizontal panel Alvin had not noticed before, and was certain he must have seen had it been there earlier. Puzzled, he bent toward it, but a shout from Rorden made him look around in surprise. The other was pointing toward the great Master Robot, where Alvin had left his own machine a few minutes before.

  It had not moved, but it had multiplied. Hanging in the air beside it was a duplicate so exact that Alvin could not tell which was the original and which the copy.

  "I was watching when it happened," said Rorden excitedly. "It suddenly seemed to extend, as if millions of replicas had come into existence on either side of it. Then all the images except these two disappeared. The one on the right is the original."

  THE C O U N C I L

  Alvin was still stunned, but slowly he began to realize what must have happened. His robot could not be forced to disobey the orders given it so long ago, but a duplicate could be made with all its knowledge yet with the unbreakable memory-block removed. Beautiful though the solution was, the mind would be unwise to dwell too long upon the powers that made it possible.

  The robots moved as one when Alvin called them toward him. Speaking his commands, as he often did for Rorden's benefit, he asked again the question he had put so many times in different forms.

  "Can you tell me how your first master reached Shalmirane?"

  Rorden wished his mind could intercept the soundless replies, of which he had never been able to catch even a fragment. But this time there was little need, for the glad smile that spread across Alvin's face was sufficient answer.

  The boy looked at him triumphantly.

  "Number One is just the same," he said, "but Two is willing to talk."

  "I think we should wait until we're home again before we begin to ask questions," said Rorden, practical as ever. "We'll need the Associators and Recorders when we start."

  Impatient though he was, Alvin had to admit the wisdom of the advice. As he turned to go, Rorden smiled at his eagerness and said quietly:

  "Haven't you forgotten something?"

  The red light on the Interpreter was still flashing, and its message still glowed on the screen.

  PLEASE CHECK AND SIGN

  Alvin walked to the machine and examined the panel above which the light was blinking. Set in it was a window of some almost invisible substance, supporting a stylus which passed vertically through it. The point of the stylus rested on a sheet of white material which already bore several signatures and dates. The last of them was almost fifty thousand years ago, and Alvin recognized the name as that of a recent President of the Council. Above it only two other names were visible, neither of which meant anything to him or to Rorden. Nor was this very surprising, for they had been written twenty-three and fifty-seven million years before.

  Alvin could see no purpose for this ritual, but he knew that he could never fathom the workings of the minds that had built this place. With a slight feeling of unreality he grasped the stylus and began to write his name. The instrument seemed completely free to move in the horizontal plane, for in that direction the window offered no more resistance than the wall of a soap bubble. Yet his full strength was incapable of moving it vertically: he knew, because he tried.

  Carefully he wrote the date and released the stylus. It moved slowly back across the sheet to its original position—and the panel with its winking light was gone.

  As Alvin walked away, he wondered why his predecessors had come here and what they had sought from the machine. No doubt, thousands or millions of years in the future, other men would look into that panel and ask themselves: "Who was Alvin of Loronei?" Or would they? Perhaps they would exclaim instead: "Look! Here's Alvin's signature!"

  The thought was not untypical of him in his present mood, but he knew better than to share it with his friend.

  At the entrance to the corridor they looked back across the cave, and the illusion was stronger than ever. Lying beneath them was a dead city of strange white buildings, a city bleached by the fierce light not meant for human eyes. Dead it might be, for it had never lived, but Alvin knew that when Diaspar had passed away these machines would still be here, never turning their minds from the thoughts greater men than he had given them long ago.

  They spoke little on the way back through the streets of Diaspar, streets bathed with sunlight which se
emed pale and wan after the glare of the machine city. Each in his own way was thinking of the knowledge that would soon be his, and neither had any regard for the beauty of the great towers drifting past, or the curious glances of their fellow citizens.

  It was strange, thought Alvin, how everything that had happened to him led up to this moment. He knew well enough that men were makers of their own destinies, yet since he had met Rorden events seemed to have moved automatically toward a predetermined goal. Alaine's message—Lys—Shalmirane—at every stage he might have turned aside with unseeing eyes, but something had led him on. It was pleasant to pretend that Fate had favored him, but his rational mind knew better. Any man might have found the path his footsteps had traced, and countless times in the past ages others must have gone almost as far. He was simply the first to be lucky.

  The first to be lucky. The words echoed mockingly in his ears as they stepped through the door of Rorden's chamber. Quietly waiting for them, with hands folded patiently across his lap, was a man wearing a curious garb unlike any that Alvin had ever seen before. He glanced inquiringly at Rorden, and was instantly shocked by the pallor of his friend's face. Then he knew who the visitor was.

  He rose as they entered and made a stiff, formal bow. Without a word he handed a small cylinder to Rorden, who took it woodenly and broke the seal. The almost unheard-of rarity of a written message made the silent exchange doubly impressive. When he had finished Rorden returned the cylinder with another slight bow, at which, in spite of his anxiety, Alvin could not resist a smile.

  Rorden appeared to have recovered himself quickly, for when he spoke his voice was perfectly normal.

  "It seems that the Council would like a word with us, Alvin. I'm afraid we've kept it waiting."