Ringworld's Children

CHAPTER 18 The Ringworld Floor

Hanuman caught the rim of the stepping disk with a hand and a foot. Rocks like rust-colored teeth waited far below him. For millions of falans his kind had known what to do about falling.

Proserpina flicked through. Hanuman caught her belt, but he wasnt needed: she had the rim of the stepping disk. "Trap," she said. She pulled herself onto an ochre rock. "Crude. Aliens?"

Hanuman said, "Tunesmith is careful. Anything might come through from the Penultimates home. Proserpina, we were told to wait. Hes sent us a service stack."

"Follow," said Proserpina. She swung around from the rim and thumped soundly against the stepping disk. Nothing happened. "Gauthiers changed the link."

"I know the protocols." Hanuman popped the controls open, freed a hand, and tapped rapidly. "Well lose Gauthiers link. Do you care where the detective and the native went?"

"Shell change the settings again. Theyre lost in the network. Go."

Hanuman swung himself down and was elsewhere.

Under a hemisphere of artificial sky, a sun burned low, red, and flattened. Veldt stretched out around Hanuman, with a lake and a low forest in the distance.

Proserpina flicked in behind him. She gaped at the lowering sun. "Was there a planet-born protector?"

"Yes. I dont know details," Hanuman said.

"I am suddenly very hungry." Proserpina loped toward the trees.

"I surmise," Hanuman said, "that protectors lose their hunger when they have too little to protect. Were you idle for a very long time?"

They were running through yellow grain, and Hanuman was falling behind. He recognized the trees ahead.

His memories as a breeder were murky. He was old, slowing down, joints starting to hurt. The troop had fought an intruder. Hanuman, fiercest of the males, got close enough to inhale a scent that sparked a rage of hunger. Hed eaten himself stupid, then estivated, then… woke like this, in a pocket of forest transplanted deep underground, with its own wandering sun. His own forest to keep him sane, and puzzles to train his newly expanded mind.

The trees were fruit trees. Lower plants grew at the edges. Ringworld life was Pak life, and all these were edible crops. Proserpinas hands plunged into the dark soil. She tore a yellow root out of the ground and ate, and gave another to Hanuman.

Presently she asked, "Wheres Tunesmith?"

"I cant call him." The pressure suit Proserpina had worked up for him was a quick fix. It didnt fit well, and it didnt have a communication link to Tunesmith. "Hell find us," Hanuman said.

"I was trapped on a single map for more than a million falans," she said. "When my Pak brethren ceased to supervise the Ringworld landscape, I continued to test for protectors in the Repair Center. The Repair Center has remained active, and I have remained passive. Im the last defense. One day I will be needed. Even now that day may not have come, but we must see. I should explore. Where can you take me?"

"Your interest is in the massing of alien craft near our sun, isnt it?"

"Yes."

Hanuman rewrote settings. "Come."

They were in a vast, dark, ellipsoidal space.

Stars glared unimpeded, light-enhanced, in walls and floor and ceiling. Spacecraft were harder to see. Tunesmith had set blinking circles round the ones hed found; he might have missed others. Thousands of ships. Hundreds of thousands of tiny blinking points: probes.

Only Proserpinas head turned.

Three long swinging booms ended in chairs equipped with lap keyboards. All three were empty. Hanuman asked, "Would you like — ?"

"Shush," she said, and continued to take it all in. Stepping disks: one visible. She couldnt see the one she was standing on. Weapons and cameras: she couldnt see those either. The star projections could mask anything.

If Tunesmith attacked, it would be from above, and Hanuman would attack too. She was ready — but that was instinct speaking. Practically speaking, if Tunesmith wanted her life, it was his. She asked, "Do you know these ships?"

"Some of them." Hanuman pointed out a few: Puppeteer, Trinoc, Outsider, Kzinti, ARM, Sheathclaws.

"Some are only observers," Proserpina said. "Some are arrayed for war. Badly. The ARM would win if they struck there and there…" Her voice wandered off. "And wreckage from this ship or this one might strike the Ringworld. That tail design confines antimatter fuel, doesnt it? Has Tunesmith considered destroying all of these fleets?"

"Tunesmith considers everything."

"But I dont know his tools. He must be at work on something! Something besides mere defensive meteor control. I wont know anything until I know what we can fight with. Or run with."

Hanuman said, "Run?"

"I speculate." Proserpina walked around the curve of the glowing wall. Under a glare of light were the bones of an ancient protector, laid out with some of his tools. The joints were swollen into knobs. Vertebrae in the back were fused.

"They had already begun to mutate," she said. "Do you know that we kill mutants? Do you still do that?"

"Of course, if they smell wrong, or behave wrong."

"This one was very good at what he did. Look at the state of the bones, the scarring from mere age. He must have survived tens of thousands of falans. Hanuman, should we have loosed our predators?"

"No."

"But these who were our own shape have occupied every ecological niche we didnt fill." She looked hard at Hanuman. Shed almost managed to ignore his mutant smell. "I see your point. Not just scavengers like this one, but brachiators like you. Mutations and evolution are good, if only you can stop it now, always now, so that your own kind need not change."

Hanuman didnt answer. She was only stating the obvious.

But Tunesmith spoke. "Your kind, your original Pak, did not survive. Thats what mutations and evolution are for, Proserpina. Something almost of your shape has multiplied into the tens of trillions. You dont like some of us? When did you ever like all of your neighbors?"

He was standing atop a chair on a boom just above her head. He could have nailed her in an instant. Too clever, too quick.

Proserpina said, "Bet. Even odds well be dead in nineteen falans, if I read these patterns right. Youve studied them longer. Hello, Tunesmith."

Tunesmith leapt down. "Hello, Proserpina, revered ancestor. Are your guests safe?"

"I see this as more urgent than their lives. You have been meddling with our basic design!"

"Yes, but not quickly enough. I need all the help I can get."

"What design changes have you made? What changes do you contemplate?"

"What would be your approach to dealing with the Fringe War?"

"I might have tried… can you give me a way to make pictures?"

Tunesmith set his chair swinging near the elliptical wall. Now the starscape was gone, and the wall was deep blue. Tunesmith waved at the wall: white lines appeared.

Proserpina jumped to another chair. She waved shapes to life. Sun. Shadow squares. Ringworld. They were white lines and curves, and then they were photographically realistic views. Proserpinas arms moved like a concert masters. The sun took on detail: magnetic fields cradled the interior. The fields changed: squeezed. The suns south magnetic pole curdled, churned, then sprayed light.

"I might have tried this," Proserpina said. "When we built the Ringworld, we set a superconductor network within the foundation structure. We can manipulate magnetic fields." The suns south pole jetted X-ray-colored flame. Slowly the sun moved north, leaving the Ringworld behind. Its gravity pulled, faint lines on the blue wall, and the Ringworld followed.

"We use the sun for thrust, up to a few meters per second squared by Interworld measurement. Beyond that—" Streamlines formed. The Ringworld moved on alone, the sun lost. "Flux of interstellar matter through the Ringworld can be steered to the axis to undergo fusion. The jet from the sun gives more fuel. A fusion exhaust confined by magnetic fields replaces the sun, bathes the Ringworld in light, and serves as a ramjet too. The Ringworld survives. We can continue to accelerate."

"Drawbacks?"

"Deceleration would be difficult but not impossible. Fields could be adjusted to thrust forward. Tides would shift."

Tunesmith waited.

"When we stopped, there would be no sun." Proserpina shrugged; the picture distorted. "It doesnt matter. We cant even begin. The sun grows too hot if we try to accelerate it. The shadow-square ring can be pulled almost closed, for shielding, but if the shadow squares fell behind or were pulled ahead, landscape would be charred.

"Worst, its too slow," Proserpina said. "The suns gravitational pull isnt enough. I can manipulate the suns magnetic fields to pull harder on the Ringworld, and it still isnt enough. Alien intruders still follow. I cant think of a way to leave them behind."

"Its the wrong principle," Tunesmith said. "You didnt know. You lack information. Did Louis Wu speak of Carlos Wus medical system? Or the spacecraft we stole from the Kzinti?"

"No."

"Ill give you details when I need to. Meanwhile — those protectors vicious enough to hold the Repair Center have not always been diligent. Theyve allowed meteor impacts, eyestorms, erosion, and sometimes an exposed sea bottom. That fool bloodsucker left thousands of places where the Ringworlds foundation shows through. I need you and your allies and servants to find these places and shake a dust into them. I have been working with others of my own kind, with the Ringworld-wide network of Ghoul species; but I havent been able to reach enough of these breaches. We move too slowly."

"What is this dust? What does it do?"

"You need only know—"

"I must judge for myself!"

"I dont want an equal partner, Proserpina! The dust spreads itself through scrith, but first the scrith must touch it. How can we put more of it in contact with the Ringworld floor?"

"My servants in the spill mountains," Proserpina said, "are useless on the flats. They suffocate. Theyll spread dust along the spill mountain edges, on the rim wall, if you can get the dust to them. Theyll travel by balloon from peak to peak."

"Good. My own spill mountain protectors have been doing that. What else?"

"Water folk," Proserpina said. "Well use them. We need to reach the spill pipe system that circulates sea bottom sediment—"

"Hup."

"Yes, flup. We use that word too. Flup accumulates in the bottoms of the seas. Without our tending, it would stay there. Topsoil all through the Ringworld would be lost under the seas in a few thousand years. Weve set in place a circulation system of spillpipes that runs under the scrith floor and up the outside of the rim wall, to fall over the edge. It becomes spill mountains. Ultimately it replenishes the earth. If your dust can be introduced into the seabottoms, can it spread into the scrith from there?"

"Yes."

"How long will it take?"

"If we begin now, less than two falans."