The Ringworld Engineers

by Larry Niven

  It couldn’t matter now. “Calling the Hindmost,” he said. “Calling the Hindmost.”

  Nothing.

  The screen wasn’t built to swivel. It faced always outward, away from the shadow squares. Annoying but informative: it could mean that the pictures were being beamed from the shadow squares themselves.

  He reduced the scale on the screen. He sent the viewpoint swooping to spinward at impossible speed until he was looking down on a world of water. He dropped like an angel in a death dive. This was fun. The Library’s facilities were considerably better than Needle’s telescope.

  The Map of Earth was old. Half a million years had distorted the continents. Or more? A million? Two? A geologist would have known.

  Louis shifted to starboard of antispinward until the Map of Kzin filled the screen: islands clustered around a plate of glare ice. And how old was this Map’s togography? Chmeee might know.

  Louis expanded the view. He hummed as he worked. He skimmed above yellow-and-orange jungle. His view crossed a broad silver band of river, and he followed it toward the sea. At the junctures of rivers there ought to be cities.

  He almost skimmed past it. A delta where two rivers joined; a pale grid pattern imposed on jungle colors. Some human cities had “green belts,” but in this kzinti city they must cover more territory than the buildings. At maximum magnification Louis could just make out patterns of streets.

  The kzinti had never liked big cities. Their sense of smell was too acute. This city was almost as big as the Patriarch’s seat of government on Kzin.

  They had cities. What else? If they had any kind of industry, they’d need ... seaports? Mining towns? Keep skimming.

  Here the jungle was scrawny. The yellow-brown of barren soil showed through in a pattern that wasn’t city-shaped at all. It looked like a melted archery target. At a guess, it was a very large and very old strip mine.

  Half a million years ago, or more, a sampling of kzinti had been dropped here. Louis didn’t expect to find mining towns. They’d be lucky to have anything left to mine. For half a million years they had been confined to one world, a world whose surface ended a few hundred feet down. But it seemed the kzinti had kept their civilization.

  They had brains, these near-cats. They had ruled a respectable interstellar civilization. Tanj, it was kzinti who had taught humans to use gravity generators! And Chmeee must have reached the Map of Kzin hours ago, in his search for allies against the Hindmost.

  Louis had followed the river to the sea. Now he skimmed his god’s-eye view “south” along the shoreline of the Map’s largest continent. He expected ports, though the kzinti didn’t use ships much. They didn’t like the sea. Their seaports were industrial cities; nobody lived there for pleasure.

  But that was in the Kzinti Empire, where gravity generators had been used for millennia. Louis found himself looking down on a seaport that would have rivalled New York harbor. It crawled with the wakes of ships barely large enough to see. The harbor had the nearly circular look of a meteor crater.

  Louis lowered the magnification, backing his viewpoint into the sky, to get an overview.

  He blinked. Had his miserable sense of scale betrayed him again? Or had he mishandled the controls?

  There was a ship moored across the harbor. It made the harbor look bathtub-sized.

  The wakes of tinier ships were still there. It was real, then. He was looking at a ship as big as a town. It nearly closed off the arc of the natural harbor.

  They wouldn’t move it often, Louis thought. The motors would chew up the sea bed something fierce. With the ship gone, the harbor’s wave patterns would change. And how would the kzinti fuel something so big? How had they fueled it the first time? Where did they find the metals?

  Why?

  Louis had never seriously wondered if Chmeee would find what he sought on the Map of Kzin. Not until now.

  He spun the magnification dial. His viewpoint receded into space until the Map of Kzin was a cluster of specks on a vast blue sea. Other Maps showed near the edges of the screen.

  The nearest Map to the Map of Kzin was a round pink dot. Mars ... and it was as far from Kzin as the Moon was from Earth.

  How could such distances be conquered? Even a telescope wouldn’t penetrate more than two hundred thousand miles of atmosphere. The idea of crossing that distance in a seagoing ship—even a ship the size of a small city—tanj!

  “Calling the Hindmost. Louis Wu calling the Hindmost.” Time was running out for Louis Wu as repairmen moved in on Needle and Chmeee culled the Map of Kzin for warriors. Louis didn’t intend to mention any of this to the Hindmost. It would only upset the puppeteer.

  What was the Hindmost doing that he couldn’t answer a call?

  Could a human even guess at the answer?

  Continue the survey, then.

  Louis ran the scale down until he could see both rim walls. He looked for Fist-of-God Mountain near the Ringworld’s median line, to port of the Great Ocean. Not there. He expanded the scale. A patch of desert bigger than the Earth was still small against the Ringworld, but there it was, reddish and barren, and the pale dot near the center was ... Fist-of-God, a thousand miles tall, capped with naked scrith.

  He skimmed to port, tracing the path they had taken following Liar’s crash. Long before he was ready, he had reached water, a wide-flung arm of the Great Ocean. They had stopped within sight of that bay. Louis drifted back, looking for what would be an oblong of permanent cloud, seen from above.

  But the eye storm wasn’t there.

  “Calling the Hindmost! In the names of Kdapt and Finagle and Allah I summon thee, God tanj it! Calling—“

  “I am here, Louis.”

  “Okay! I’m in a library in the floating city. They’ve got a map room. Look up Nessus’s records of the map room we—“

  “I remember,” the puppeteer said coolly.

  “Well, that map room showed old tapes. This one is running on present time!”

  “Are you safe?”

  “Safe? Oh, safe enough. I’ve been using superconductor cloth to make friends and influence people. But I’m trapped here. Even if I could bribe my way out of the city, I’d still have to get past the Machine People station on Sky Hill. I’d rather not shoot my way out.”

  “Wise.”

  “What’s new at your end?”

  “Two data. First, I have holograms of both of the other spaceports. All of the eleven ships have been rifled.”

  “The Bussard ramjets gone? All of them?”

  “Yes, all.”

  “What else?”

  “You cannot expect rescue from Chmeee. The lander has set down on the Map of Kzin in the Great Ocean,” the puppeteer reported. “I should have guessed. The kzin has defected, taking the lander with him!”

  Louis cursed silently. He should have recognized that cool, emotionless tone. The puppeteer was badly upset; he was losing control of the finer nuances of human speech. “Where is he? What’s he doing?”

  “I watched through the lander’s cameras as he circled the Map of Kzin. He found a capacious seagoing ship—“

  “I found it too.”

  “Your conclusions?”

  “They tried to explore or colonize the other Maps.”

  “Yes. In known space the kzinti eventually conquered other stellar systems. On the Map of Kzin they must have looked across the ocean. They were not likely to develop space travel, of course.”

  “No.” The first step in learning space travel is to put something in orbit. On Kzin, low orbital velocity was around six miles per second. On the Map of Kzin, the equivalent was seven hundred and seventy miles per second. “They couldn’t have built too many of these ships either.
Where would they get the metals? And the voyages would take decades, at least. I wonder how they even knew there were other Maps.”

  “We may guess that they launched telescopic camera equipment aboard rockets. The instruments would have to perform quickly. A missile could not go into orbit. It would rise and fall back.”

  “I wonder if they reached the Map of Earth? It’s another hundred thousand miles past Mars ... and Mars wouldn’t make a good staging area.” What would kzinti have found on the Map of Earth? Homo habilis alone, or Pak protectors too? “There’s the Map of Down to starboard, and I don’t know the world to antispinward.”

  “We know it. The natives are communal intelligences. We expect that they will never develop space travel. Their ships would need to support an entire hive.”

  “Hospitable?”

  “No, they would have fought the kzinti. And the kzinti have clearly given up the conquest of the Great Ocean. They seem to be using the great ship to block off a harbor.”

  “Yeah. I’d guess it’s a seat of government too. You were telling me about Chmeee.”

  “After learning what he could by circling above the Map of Kzin, he hovered above the great ship. Aircraft rose and attacked him with explosive missiles. Chmeee allowed this, and the missiles did no harm. Then Chmeee destroyed four aircraft. The rest continued the attack until weapons and fuel were exhausted. When they returned to the ship, Chmeee followed them down. The lander presently rests on a landing platform on the great ship’s conning tower. The attack continues. Louis, is he seeking allies against me?”

  “If it’s any comfort to you, he won’t find anything that can go up against a General Products hull. They can’t even hurt the lander.”

  Long pause; then “Perhaps you’re right. The aircraft use hydrogen-burning jets and missiles propelled by chemical explosives. In any case, I must rescue you myself. You must expect the probe at dusk.”

  “Then what? There’s still the rim wall. You told me stepping discs won’t send through scrith.”

  “I used the second probe to place a pair of stepping discs on the rim wall as a relay.”

  “If you say so. I’m in a building shaped like a top, at the port-by-spinward perimeter. Set the probe to hover until we decide what to do with it. I’m not sure I want to leave yet.”

  “You must.”

  “But all the answers we need could be right here in the Library!”

  “Have you made any progress?”

  “Bits and pieces. Everything Halrloprillalar’s people knew is somewhere in this building. I want to question the ghouls too. They’re scavengers, and they seem to be everywhere.”

  “You only learn to ask more questions. Very well, Louis. You have several hours. I will bring the lander to you at dusk.”

  Chapter 22 -

  Grand Theft

  The cafeteria was halfway down the building. Louis gave thanks for a bit of luck: the City Builders were omnivores. The meat-and-mushroom stew could have used salt, but it filled the vacuum in his belly.

  Nobody used enough salt. And all the seas were fresh water, except for the Great Oceans. He might be the only hominid on the Ringworld who needed salt, and he couldn’t live without it forever.

  He ate quickly. Time pressed on the back of his neck. The puppeteer was already skittish. Surprising that he hadn’t already fled, leaving Louis and the renegade Chmeee and the Ringworld to their similar fates. Louis could almost admire the puppeteer for waiting to rescue his press-ganged crewman.

  But the puppeteer might change his mind when he saw the repair crew coming at him. Louis intended to be back aboard Needle before the Hindmost turned his telescope in that direction.

  He went back to the upper rooms.

  The reading screens he tried all gave unreadable script and no pictures and no voice. Finally, at one of a bank of screens, his eye caught a familiar collar.

  “Harkabeeparolyn?”

  The librarian turned. Small flat nose; lips like a slash; bald scalp and a fine, delicate skull; long, wavy white hair ... and a nice flare to her hips, and fine legs. In human terms she’d have been about forty. City Builders might age more slowly than human beings, or faster; Louis didn’t know.

  “Yes?”

  There was a snap in her voice. Louis jumped. He said, “I need a voice-programmed screen and a tape to tell me the characteristics of scrith.”

  She frowned. “I don’t know what you mean. Voice-programmed?”

  “I want the tape to read to me out loud.”

  Harkabeeparolyn stared, then laughed. She tried to strangle the laugh, and couldn’t; and it was too late anyway. They were the center of attention. “There is no such thing. There never has been,” she tried to whisper, but the giggle bubbled up and made her voice louder than she wanted. “Why, can’t you read?”

  Blood and tanj! Louis felt the heat rising in his ears and neck. Literacy was admirable, of course, and everybody learned to read sooner or later, at least in Interworld. But it was no life or death matter. Every world had voice boxes! Why, without a voice box, his translator would have nothing to work with!

  “I need more help than I thought. I need someone to read to me.”

  “You need more than you paid for. Have your master renegotiate.”

  Louis wasn’t prepared to risk bribing this embarrassed and hostile woman. “Will you help me find the tapes I need?”

  “You’ve paid for that. You’ve even bought the right to interrupt my own researches. Tell me just what you want,” she said briskly. She tapped at keys, and pages of strange script jumped on her screen. “Characteristics of scrith? Here’s a physics text. There are chapters on the structure and dynamics of the world, including one on scrith. It may be too advanced for you.”

  “That, and a basic physics text.”

  She looked dubious. “All right.” She tapped more keys. “An old tape for engineering students on the construction of the rim transport system. Historical interest only, but it might tell you something.”

  “I want it. Did your people ever go under the world?”

  Harkabeeparolyn drew herself up. “I’m sure we must have. We ruled the world and the stars, with machines that would make the Machine People worship us if we had them now.” She played with the keyboard again. “But we have no record of that event. What do you want with all this?”

  “I don’t quite know yet. Can you help me trace the origin of the old immortality drug?”

  Harkabeeparolyn laughed, softly this time. “I don’t think you can carry that many book spools. Those who made the drug never told their secret. Those who wrote books never found it. I can give you religious spools, police records, confidence games, records of expeditions to various parts of the world. Here’s the tale of an immortal vampire who haunted the Grass Giants for a thousand falans, growing uncomfortably cunning with the years, until—“

  “No.”

  “His hoard of the drug was never found. No? Let me see ... Ktistek Building joined the Ten because the other buildings ran out of the drug before Ktistek did. A fascinating lesson in politics—“

  “No, forget it. Do you know anything about the Great Ocean?”

  “There are two Great Oceans,” she informed him. “They’re easy to pick out on the Arch at night. Some of the old stories say the immortality drug came from the antispinward Ocean.”

  “Uh-*huh*.”

  Harkabeeparolyn smirked. The small mouth could look prissy. “You are naive. One can pick out just two features on the Arch with the naked eye. If anything valuable came from far away and comes no more, somebody will say that it came from one of the Great Oceans. Who can deny it, or offer another origin?”

  Louis sighed. “You’re probably right.”
/>   “Luweewu, how can these questions possibly be connected?”

  “Maybe they can’t.”

  She got the spools he’d requested, and another: a book for children, tales of the Great Ocean. “I can’t think what you’ll do with these. You won’t steal them. You’ll be searched when you leave, and you can’t carry a reading machine with you.”

  “Thank you for your help.”

  He needed someone to read to him.

  He didn’t have the nerve to ask random strangers. Perhaps a nonrandom stranger? There had been a ghoul in one of these rooms. If ghouls in the shadow farm knew of Louis Wu, perhaps this one did too.

  But the ghoul was gone, leaving only her scent.

  Louis dropped into a chair in front of a reading screen and closed his eyes. The useless spools bulged in two of his vest pockets. I’m not licked yet, he thought. Maybe I can find the boy again. Maybe I can get Fortaralisplyar to read to me, or to send someone. It’ll cost more, of course. Everything always costs more. And takes longer.

  The reading machine was a big, clumsy thing, moored to the wall by a thick cable. The manufacturer certainly hadn’t had superconducting wire. Louis threaded a spool into it and glared at the meaningless script. The screen’s definition was poor, and there was no place for a speaker grid. Harkabeeparolyn had told the truth.

  I don’t have time for this.

  Louis stood up. He had no choices left.

  The roof of the Library was an extensive garden. Walks spiraled out from the center, from the top of the spiral stairs. Giant nectar-producing flowers grew in the rich black soil between the walks. There were small dark-green cornucopias with tiny blue flowers in the mouths, and a patch of weenie plant in which most of the “sausages” had split to give birth to golden blossoms, and trees that dropped festoons of greenish-yellow spaghetti.

  The couples on the scattered benches gave Louis his privacy. He saw a good many blue-robed librarians, and a tall male librarian escorting a noisy group of Hanging People tourists. Nobody had the look of a guard. No ramps led away from the Library roof: there was nothing to guard, unless a thief could fly.