by Larry Niven
The others stirred.
Tunesmith's deep-radar window showed one ARM ship diving through the puncture hole--leaving hard-won turf abandoned, but safeguarding data from its explorations, unless some ambush waited beneath the Ringworld floor. The other accelerated hard, running down the storm's axis in a channel of clear air, the pupil of the eye.
Kzinti had deep-radar too. Two lens ships were diving. Fire followed them down.
The eyestorm flashed to a blue-white glare.
The Hindmost killed the zoom window before it could blind them. On a less expanded view--Tunesmith must have a camera on one of the shadow squares--a star glared near the Other Ocean, as big as... too big... far too big.
The puppeteer said, "I believe one of the ARM ships exploded. Antimatter. We'll have a hole the size of..." The Hindmost thought it through, then folded into himself and was silent.
The eyestorm was gone, blasted apart. Cloud patterns showed an expanding ring of shock wave crossing seas and gray-green land. A hemisphere of cloud enveloped a dimming fireball.
"What has happened here?"
Tunesmith and the little chimp-protector were on the stepping disk: a sorcerer confronting wayward apprentices, demanding explanations. Louis's throat closed on him. It felt like he should have stopped this. It felt like Tunesmith would, should blame him.
"Antimatter explosion," Acolyte said.
"Is there a hole under that cloud?"
The question was already silly: the dome of cloud was dimpled in the center. It was being sucked into interstellar space. When Acolyte didn't answer, Louis said, "There was already a hole--"
"Of course. We have to move fast," Tunesmith said. "Come." He had the lip of the stepping disk up and was redirecting it.
Louis found his voice. "Sure, now's a good time to move fast. You've brought the war home! And now the air's draining out of the Ringworld!"
What had been a fireball was nearly gone. The Ringworld floor was naked scrith within a slowly expanding ring of cloud. Clouds streamed toward the hole.
And Tunesmith had Louis by the forearm. He walked them to a stepping disk.
Hanuman's eyes took it all in in one sweep:
He'd bent the laws that governed this universe and a hypothetical other. His mission was a total success. And none of it mattered. The Ringworld held everything worth saving, and the Ringworld floor was ripped open.
The puncture was on the far side of the arch. That was both good and ill. Death would be a long time marching around the curve to reach them here; but Tunesmith's countermeasures would have to cross that same gap.
The aliens saw it too. The most alien was the eldest, the most experienced, perhaps the wisest, and that one had shut down his mind. The hominid had lost hope. The youngest, the nothing-like-a-big-cat, was--like Hanuman--waiting for someone to solve it.
Tunesmith?
Tunesmith was in motion while Hanuman was still catching up. The Ghoul protector showed no doubts. When Tunesmith and Louis Wu vanished, the little protector followed. Tunesmith would fix it.
Machinery on a Brobdingnagian scale had been moved into the workstation under Mons Olympus.
Tunesmith dropped Louis's arm and moved among his instruments at a sprint. The little protector, Hanuman, scampered after.
Acolyte popped up next to Louis. "Louis, what's happening?"
"The air's draining out of the Ringworld."
"That would be... the end of everything?"
"Yah. Starting on the far side. We might have days, but only because the Ringworld is so endlessly big. I have no idea what Tunesmith thinks he's doing."
"What is that massive structure? I've seen it--"
Hanuman rejoined them. "That is a meteor plug, largest version. Of course it was never tested."
It was the shape of an aspirin tablet and roughly the size of the Twin Peaks arcology or a small mountain, still small compared to the puncture in the Ringworld. Louis said, "I remember. It was in one of the caverns. He set it moving here on big stacks of float plates."
They watched it slide into the hole in the floor and fall, guided by magnetic fields toward the base of the linear launcher. Tunesmith was at the edge, watching. Louis and Acolyte went to join him.
Forty miles from the roof to the floor of the RepairCenter ran the loops of the linear launcher. It was way overbuilt for something as small as Hot Needle of Inquiry. It would better accommodate something like this half-mile-wide package of Tunesmith's. The launcher's bottom sat on an array of float plates, and that was moving to adjust its aim.
The package was near the bottom now, still falling, but slowing.
Tunesmith saw them watching. Immediately he hustled them away from the hole in the floor.
Lightning roared at their backs. Louis turned to see something tremendous flash past, out through the crater in Mons Olympus and gone.
Acolyte's ears were curled into tight knots. Hanuman lifted his hands from his ears and said something inaudible. Louis couldn't hear anything. His ears still held the roar and agony of that lightning blast.
Louis didn't lose his deafness for some time. Acolyte recovered much faster. Louis could see the Kzin discussing... whatever... with Tunesmith and Hanuman while they all followed the action in a wall display of the Meteor Defense Room. The Hindmost remained in footstool mode.
Louis could only watch.
Tunesmith's meteor-plug package drifted toward the sun. Needle had been launched at a tenth of lightspeed; the launch system was capable of that. But over such a distance the package's fall seemed sluggish.
In a zoom window the puncture showed as a black dot on landscape that looked lunar: clear and sharp and barren of water's silver or the dark gray-green of life. Louis guessed the puncture was sixty to seventy miles across. A ring of fog surrounded it, bigger than the Earth and still growing.
The Ringworld was not yet aware of its death. Air and water would flow into the hole and out into vacuum, but first it all had to move... from up to three hundred million miles around each arc before the shock could reach the Ringworld's far side, the Great Ocean, here. Not much would be lost in a hundred and sixty minutes, while Tunesmith's package crossed the Ringworld's diameter. Even the Other Ocean wouldn't have begun to boil yet.
Hanuman wandered over. He said--loudly, spitting his consonants; it was fun to watch his lips--"I have been in this state for less than a falan. I still cannot grasp the scale of things. I did not grow up in a universe fifty billion falans old, on a ring spinning around one fleck of light among ten-to-the-twentieth of flecks. There were not that many of anything! My world was small, cozy, easily grasped."
"You get used to it," Louis said. He could barely hear himself. "Hanuman, what is that? What can it do? We're losing our atmosphere!"
"I know little."
"Share it with me," Louis demanded.
"Two bright minds with similar goals will solve problems in similar ways. The Vampire protector Bram saw a need to plug meteor holes. His first meteor plugs were small, but his mass driver under Mons Olympus is hundreds of falans old and hugely overbuilt. The Fist-of-God meteoroid impact must have frightened Bram witless.
"Tunesmith builds bigger yet. That package is his biggest effort." Hanuman was constantly in motion, bouncing around Louis as he spoke, arms swinging. "We shall see it in action. Tunesmith wants us to observe on site. If there is partial failure, then we must see what must be redesigned."
"This double-X-large meteor patch, how does it work?"
"I would be guessing."
"It's never been tested?"
"Tested when? You were stored in the 'doc for less than a falan. Tunesmith made and trained four Hanging People protectors, built a nanotech factory to make bigger meteor p
lugs, monitored the Fringe War, designed several probe ships, built a stepping-disk factory, redesigned your Hot Needle of--"
"He's been busy?"
"He's been crazy as a stingbug hive city! And if the plug doesn't work, it's all for nothing."
"Do you have children?"
"Yes, and they have children. Since Tunesmith made me, I've not had the chance to count them, nor even to sniff them. Of course they are all forfeit to Tunesmith's schemes and the Fringe War."
"Aren't we all. Should Tunesmith have taken such a risk?"
"How should I judge?" Hanuman's frantic dance, the hands pounding his chest, would have been an uncontrollable rage in any human. "Tunesmith implies that the greatest risk was not to act. Louis, how can you remain so still?"
"Fifty years... two hundred falans of yoga. I'll teach you."
"I must act," Hanuman said, "but not because to be still is wrong. It may be that way with Tunesmith. How can I know? I am enraged with no target."
The sun's gravity was bending the package's course minutely.
Tunesmith and Acolyte walked over. Tunesmith asked, "Louis, do you have your hearing back? Have you rested?"
"I slept. Where did you land Long Shot?"
"Why would I tell you that?" Tunesmith waved it off. "You and Acolyte and Hanuman must observe my plug in action. Has Hanuman told you anything?"
"It's a double-X-large-size meteor plug."
"Good. I have a stepping disk in place--"
"You saw this coming," Louis said.
"I did."
"Could you have stopped it?"
"How?"
"Don't steal Long Shot?"
"I need to understand the Quantum II hyperdrive. Louis, you must see that the Fringe War would never have stayed in the comets. These Ball World species covet the technology that made the Ringworld. It isn't the Ringworld they want to preserve. They want the knowledge, and to keep it from each other."
Louis nodded. It wasn't a new thought. "Scrith armor. Cheap fusion plants."
"Trivia," Tunesmith said. "The Ringworld engineers needed motors to spin this structure up. They must have confined a hydrogen mass equivalent to a dozen gas giant Ball Worlds, then fed it all through force fields arrayed to act as hydrogen fusion motors. Your Ball World bandits don't have decent magnetic control, and what they have won't scale up. They might learn something by studying our motors on the rim wall. They would study the Ringworld. They need not preserve it. Am I talking sense?"
"Maybe."
"Louis, I want you in place to observe the meteor patch as it deploys."
"Tunesmith, it bothers me to be expendable."
"I don't use the word, Louis. I don't use the concept. All life dies, all life resists dying. I would not put you in unneeded danger."
"Interesting word."
"I have a stepping disk in place from which you may observe. A sight not to be missed. Hanuman will go. Will you? Acolyte, will you go? Or will you rest here in comfort to learn if all we know has been destroyed?"
Acolyte looked to Louis.
Louis threw up his hands. "Stet. You want us in pressure suits?"
"With all my heart," Tunesmith said. "Use full gear."
Chapter 9 -
View from a Height
They geared up in Needle and flicked from there. The Hindmost wasn't with them. They'd left the puppeteer in a depressed and uncommunicative state.
At lightspeed via stepping disks, they'd arrive ahead of Tunesmith's plug package.
Acolyte wore Chmeee's spare pressure suit, retrieved from Needle's stores. He looked like a bunch of grapes. Hanuman, in a skintight suit with a fishbowl helmet, went first. Louis stepped onto the plate.
The bottom dropped out.
Louis hadn't expected free fall. He hadn't expected to be thousands of miles up, either. He snatched at something: Hanuman's hand. Hanuman pulled him to the stepping disk.
The Ringworld, two or three thousand miles below, skimmed past at ferocious speed. It looked infinite in all directions. The rim walls were too distant to show as more than sharp lines.
Acolyte yowled.
Louis didn't dare reach for the thrashing, terrified Kzin. Acolyte's father's spare pressure suit was all balloons, but there were waldo claws on all four limbs. It would have been like reaching into a threshing machine.
"It's all right. You have attitude jets," Louis shouted. "Use them when you feel like it."
The yowling stopped.
Louis's magnetic soles held him down. Hanuman had turned the stepping disk off. Otherwise they'd be back aboard Needle.
"Plenty of time, Acolyte," Louis said. "We're orbiting the sun." Louis held his voice calm, soothing. He's only twelve. "Essentially we're standing still, and the Ringworld goes at the usual seven hundred and seventy miles per second, so we'll see the whole thing go under us in seven and a half days. Hanuman--?"
"Eight," Hanuman said. "Eight stepping disks are now in orbit. Tunesmith intended more. This was the nearest. I've committed the stepping-disk system to memory. If we need to reach the surface, there's a service stack not too far, but meanwhile we can see it all. Can you pick out the puncture?"
"I don't see it yet."
"Look antispin."
"It's behind us? Stet, I have it. It looks like a target." Airless moonscape rimmed with cloud, scored with lines pointing inward toward a black dot.
The land racing below them still had river networks lined with the dark green of life. Through the land a white streak ran to antispin. Louis thought he knew what that was, but it was less urgent than the puncture. "Acolyte--?"
"I see the wound. I do not see the plug package."
"I haven't found that either," Hanuman said. 'Too small. Tunesmith, are you with us?"
"Half hour delay," Louis reminded him. "Sixteen minutes each way, lightspeed." This was a protector? But upgraded from an animal. You didn't expect a protector to forget things... and Hanuman must be very accustomed to Tunesmith's guidance.
Acolyte bounced against the stepping disk. Magnetic boots clung. He stood uncertainly. "My father tried to tell me about free fall," he said. "I don't think he ever feared it."
Tunesmith spoke from sixteen minutes in the past. "I've sent the signal to deploy the double-X-large meteor plug. Tell me what you see, all three of you. Be free to interrupt each other, I can sort your voices."
A lamp lit above the target.
It didn't look much brighter than a street lamp, but its size... Louis squinted past the glare. "Something unfolding. Tunesmith, it looks like fire salamanders mating... or a balloon inflating... it's bulking up into a shape like a sailing ship's life preserver. Jets firing at fusion temperatures. What have you got there, Tunesmith?"
Acolyte: "It's settling. Slowing. A torus. It's much wider than the puncture, a thousand to two thousand klicks across. Was this what you wanted to hear?"
Hanuman: "The scrith foundation that holds the Ring together demonstrates tremendous tensile strength. I've done the numbers. The forces that hold scrith together would generate showers of quarks if pulled apart. A bag made of such material would be strong enough to confine a hydrogen fusion explosion. There's risk, Tunesmith, but it seems to be holding."
Acolyte: "It's settling--"
Louis: "--enclosing the puncture. Leaving the puncture exposed like a bull's-eye on a target. I'm guessing your balloon stands fifty miles tall, so it'll confine the atmosphere as long as it holds."
Hanuman: "Tunesmith, how good an insulator is a scrith balloon? We wouldn't see it if it weren't leaking energy. When it cools enough, it'll collapse. Tunesmith, it will leak air. The ground beneath will be uneven."
&nbs
p; Answer came there none. Tunesmith's reaction was a Ringworld diameter away.
So he must have spoken sixteen minutes ago. "Watch for the second package," the protector said. "Tell me if it settles inside the ring."
Acolyte: "I don't see anything. Louis? Hanuman?"
Louis: "There won't be a meteor trail--"
Acolyte: "Rocket! I see it. Fusion, by its color. Settling slowly at the edge of the hole. It's down."
Louis: "We're drifting too far. I can't see the puncture any more."
Hanuman bent over the rim of the stepping disk. "I'll fix that. The next stepping disk is thirty degrees around the Ringworld arc. Ready?"
They flicked.
The Ringworld flowed beneath them. They'd jumped thirty degrees, about fifty million miles. Louis, looking ahead of him, found a line of white several worlds wide, and a brighter line peeping above its center. Acolyte said, "There it is. We can't see detail, Tunesmith. We won't be over it for half a day."
Louis: "There's a zoom function in our faceplates. Tunesmith, I don't see any change. Your balloon plug is still inflated. Everything outside the balloon is fog. We've lost a... few percent of the Ringworld already."
Around the edges of the fog, the land would be ravaged by shock waves running through air, sea, earth, and the scrith foundation. Weather patterns would be shattered.... Louis realized he was being optimistic. He was assuming that Tunesmith would plug the hole, stop the loss.
He had once estimated the Ringworld's population at thirty trillion, with hominid species in every possible ecological niche. That vast plain of fog would be water droplets condensed by a drop in pressure. Ecologies under that fog blanket would be dehydrated and suffocating. Around it they'd soon be ravaged by climate change.
But only if Tunesmith made a miracle.
"I think a ship in stasis crashed to antispin of the puncture," Louis said. "I can't see it from here."
Hanuman said, "We won't be over it for half a day. I'm going to flick us home."
A moment later--plus a quarter hour--they were aboard Needle.
Moments afterward, so was Tunesmith. "Hanuman, report," he said.
