Free The City and the Stars / The Sands of Mars by Arthur C. Clarke Page B

in front of us now— and he could not go far along it. He would have to turn back, as you would turn back if you started to cross a plank between those towers.”
    “But why?” asked Alvin. “There must have been a time—”
    “I know, I know,” said Khedron. “Men once went out over the whole world, and to the stars themselves. Something changed them and gave them this fear with which they are now born. You alone imagine that you do not possess it. Well, we shall see. I’m taking you to Council Hall.”
    The Hall was one of the largest buildings in the city, and was almost entirely given over to the machines that were the real administrators of Diaspar. Not far from its summit was the chamber where the Council met on those infrequent occasions when it had any business to discuss.
    The wide entrance swallowed them up, and Khedron strode forward into the golden gloom. Alvin had never entered Council Hall before; there was no rule against it— there were few rules against anything in Diaspar— but like everyone else he had a certain half-religious awe of the place. In a world that had no gods, Council Hall was the nearest thing to a temple.
    Khedron never hesitated as he led Alvin along corridors and down ramps that were obviously made for wheeled machines, not human traffic. Some of these ramps zigzagged down into the depths at such steep angles that it would have been impossible to keep a footing on them had not gravity been twisted to compensate for the slope.
    They came at last to a closed door, which slid silently open as they approached, then barred their retreat. Ahead was another door, which did not open as they came up to it. Khedron made no move to touch the door, but stood motionless in front of it. After a short pause, a quiet voice said: “Please state your names.”
    “I am Khedron the Jester. My companion is Alvin.”
    “And your business?”
    “Sheer curiosity.”
    Rather to Alvin’s surprise, the door opened at once. In his experience, if one gave facetious replies to machines it always led to confusion and one had to go back to the beginning. The machine that had interrogated Khedron must have been a very sophisticated one— far up in the hierarchy of the Central Computer.
    They met no more barriers, but Alvin suspected that they had passed many tests of which he had no knowledge. A short corridor brought them out abruptly into a huge circular chamber with a sunken floor, and set in that floor was something so astonishing that for a moment Alvin was overwhelmed with wonder. He was looking down upon the entire city of Diaspar, spread out before him with its tallest buildings barely reaching to his shoulder.
    He spent so long picking out familiar places and observing unexpected vistas that it was some time before he paid any notice to the rest of the chamber. Its walls were covered with a microscopically detailed pattern of black and white squares; the pattern itself was completely irregular, and when he moved his eyes quickly he got the impression that it was flickering swiftly, though it never changed. At frequent intervals around the chamber were manually controlled machines of some type, each complete with a vision screen and a seat for the operator.
    Khedron let Alvin look his fill. Then he pointed to the diminutive city and said: “Do you know what that is?”
    Alvin was tempted to answer, “A model, I suppose,” but that answer was so obvious that he was sure it must be wrong. So he shook his head and waited for Khedron to answer his own question.
    “You remember,” said the Jester, “that I once told you how the city was maintained— how the Memory Banks hold its pattern frozen forever. Those Banks are all around us, with all their immeasurable store of information, completely defining the city as it is today. Every atom of Diaspar is somehow keyed, by forces we have forgotten, to the matrices buried in these walls.”
    He waved toward the perfect, infinitely detailed simulacrum of