The Clockwork Rocket

by Greg Egan

  Yalda braced her tympanum.

  “Eight.”

  In less than a flicker the wave of compression came hurtling back up through the rock. Through the bench she felt the first insistent tremor from the nearest ignition points, then the pounding of ever more engines reached her until even the most distant were hammering at her body. For one terrified moment she could discern no change in her weight—her skin reported nothing but the bench’s vibrations—then she tried to raise an arm and was rewarded with unambiguous resistance, easily overcome but enough to banish her fears. If the engines had been too weak to lift the mountain, she would not have felt this. No amount of ineffectual flame and fury, no mere buffeting and shaking, could have mimicked the glorious signature of acceleration.

  Belatedly, she checked the balance beside her, isolated in a vibration-deadening frame from the jittering floor. The polished hardstone scrood-weight was stretching the spring by close to twice the original amount, putting the thrust within a notch of its intended value. There could be no doubt that the Peerless was rising, climbing ever faster into the sky.

  Chilled air flowed through the room; the cooling system was working. Not only had the mountain failed to collapse into smouldering rubble, or squat on the ground building up heat until it set the world on fire, it wasn’t even going to cook its passengers alive.

  Yalda’s relief turned to exhilaration. She tried to picture the events below: flame spilling out from the hole the severed mountain had left in the ground, hot gas and burning dust swirling across the plain to engulf the empty buildings of Basetown. If she envied Eusebio anything now, it was the sight of a dazzling white streak of fire splitting the eastern sky, when all she had before her was this trembling red-lit cave. But no matter; she’d write him a note and have it carved in stone to be passed down the ages: You witnessed the launch in all its splendor, but when I looked down on your world it was small as a pebble.

  The room shuddered; Yalda was thrown sideways in her restraint, her euphoria banished. She looked to the gyroscopes at the center of the room, struggling to interpret their quivering. She’d sat with Frido and Eusebio, calculating the motion of these devices under all manner of calamities, but now her mind was blank and she couldn’t match what she was seeing to any of those predictions.

  Babila caught her eye with a series of symbols on an outstretched palm: One engine failed, but we’ve recovered. That made sense; if the rocket had remained unbalanced and the mountain had started tumbling, the axes of the gyroscopes would have ended up far from their starting markers. The machines feeding the other engines had detected the incipient swerve, and those positioned to compensate were doing so.

  One feed had malfunctioned, out of three dozen. That was no worse than the proportion of recruits who’d pulled out. The machinists responsible for it wouldn’t even leave their benches to attempt repairs while the engines were still producing extra thrust, laboring to overcome the world’s gravity. This was failure at a level they’d anticipated, not an emergency. It could wait the six chimes until their weight became normal.

  Yalda checked the clock; a single chime had passed. The Peerless would be about a separation above the ground now. She longed for a window—and some magic that would make it worthwhile by granting her a view through the flames—but even the lucky people in the highest observation chambers would only be able to see the distant horizon, gradually shrinking until it was obscured by the glare of the exhaust. By the time their path had curved sufficiently to allow them to look back on their starting point, the world really would appear as small as a pebble.

  The room lurched again, a sickening swing abruptly curtailed. Yalda steadied herself and peered anxiously at the gyroscopes; the rocket remained level. Had a second engine cut out, or had the first recovered spontaneously? Even two dead engines didn’t threaten their stability, but ongoing failures at this rate certainly would. Whatever had happened, the machinists on site would leave their benches now, make inspections and report.

  Yalda looked across at Frido; he signaled tersely: Patience. Until they had more information there was nothing the navigators could do. The Peerless was still under control, and still ascending at close to the target rate. If that much of their luck continued, in two more chimes they’d reach the point where they could shut down all the engines without fear of plummeting back to the ground. In a wide, slow orbit around the sun, they could assess the situation and make repairs. Dispiriting as such a setback would be, better a delay and some damage to morale than have the Peerless turn into a spiraling firework.

  For a third time, the rocket staggered and then caught itself. Yalda felt as if she were back on the footbridge over the trench, paralyzed by the sight of the abyss beneath her—and watching the ropes that supported her snapping one by one. Where were the reports from the machinists? She stared at the bank of paper tape writers connected to the signaling ropes. Though the devices had never been used outside the Peerless, they’d proved invaluable during the construction phase. Only adjacent chambers were connected directly, but messages that needed to go farther could be relayed from chamber to chamber. These particular units had been tested thoroughly—most recently when the machinists had first reached their stations prior to the launch.

  Finally, one writer began disgorging a message. Babila could reach it without leaving her bench; she grabbed the end of the strip and peered at it, frowning, before the message was complete. Having the thing print actual symbols would have made it too complicated, so they’d devised and memorized a simple code that could be transmitted by tugging on either of two ropes.

  From chamber four, Babila wrote on her palm, stretching her hand to fit more words. Feed stopped. Waiting. Chamber four was out at the rim; the message had reached them via two intermediaries.

  That would have been the first failure, with the machinist following the protocol and delaying inspection until the thrust was reduced and movement became easier. But then almost immediately, another message arrived: From chamber three. Feed stopped. Investigating.

  Chamber three was also at the rim, right next to chamber four. What source of failure, Yalda wondered, could depend on proximity? Dust from construction rubble—somehow missed in all the inspections—shaken out of its hiding place and rendered airborne by the vibrations?

  That made no sense, though. Coarse enough debris might jam the clockwork—delaying the feed’s opening in the first place—but Yalda was sure there was no part of the machinery where grit in the cogs could cause the feed to close once it was already open.

  Chamber four, then chamber three… she wasn’t going to wait to learn where the third failure had been. She held up her hand to Babila. Message to chamber two, and all its neighbors: Make a full inspection.

  Babila started working the ropes. Frido caught Yalda’s eye.

  Sabotage? he asked. His face bore an expression of disbelief. This was not a scenario they’d anticipated.

  Just being cautious, she replied. Whatever the cause of the first two failures, it could do no harm to test the assumption that their proximity was more than a coincidence.

  Yalda turned to the clock; in a couple of lapses they would reach planetary escape velocity. The protocols dictated that three failures was the limit; one more and she’d have no choice but to shut down all the engines as soon as it was safe and let the Peerless drift around the sun until they’d diagnosed and remedied the problem.

  Another of the tape writers started up. This one was out of Babila’s reach; she unstrapped herself and lumbered across the floor, pausing to strengthen her legs with extra flesh from her torso. As she read the message her tympanum twitched, as if she couldn’t stop herself silently cursing. Then she turned away from the machine and wrote across her chest: From chamber two. Intruder sighted. Pursuing.

  Yalda and Frido joined her in spreading the news—first to those chambers that were close to number two but where the message would not have been seen already. The rope system was faster than any messenge
r on foot, but it was beginning to seem hopelessly slow and unwieldy.

  When they’d finished Yalda stood beside the tape writers, disoriented and frustrated. An intruder? Accepting the notion was difficult enough, but her role made it even harder to bear. She should have been running through the feed chambers trying to catch the saboteur, not hanging around here playing message clerk.

  Six chimes from ignition—precisely on schedule—the other feeds proved that they were operating flawlessly by cutting back the rocket’s thrust from two gravities to one, all the while smoothly maintaining the balancing act compensating for the dead engines. The Peerless was four times as far from the center of the world now than it had been at launch—and moving almost five times faster than it needed to be to continue its ascent indefinitely. To the astronomers tracking their flight from the ground, the journey would appear to be proceeding uneventfully. One more jammed feed, though, and the whole world would have known that they were in trouble.

  Yalda tentatively relaxed her tympanum; the hammering of the engines was still unpleasant, but it wasn’t intolerable.

  “I think speech is viable again,” she shouted at her companions.

  What? Babila wrote on her chest.

  Yalda turned to Frido. “So who’s the number one candidate to send in a saboteur?”

  Frido’s expression made it clear that he knew who she had in mind, but he still balked at the idea. “Six gross casualties, all innocent people…?”

  “If it was Acilio, he wasn’t trying to murder us,” Yalda replied. “If that had been the aim he would have sent someone after the gyroscopes; he could have crashed the Peerless when it was barely off the ground, and made a big display of it for everyone watching from Zeugma.”

  “So he wanted us drifting?” Frido suggested. “Demoralised by the engine failures, hanging around in orbit until we’d taken every feed apart and inspected every component a dozen times. Nobody dead, but enough of a setback to humiliate Eusebio.”

  “Who’s this Acilio?” Babila asked.

  “A Councilor in Zeugma,” Yalda explained wearily. “His grandfather and Eusebio’s grandfather had a business dispute—”

  Babila held up a hand to stop her. “I don’t care about anyone’s squabbling ancestors. His name and position should be enough for the people who return to find him and kill him.”

  Yalda said, “Yeah, we’re not interested in those barbaric generations-long feuds.”

  One of the tape writers sprung to life; Yalda stepped forward and began decoding the message. “From chamber one,” she read. “Intruder captured. Claims he’s alone. Bringing him to you.”

  Half a bell later, four machinists entered the navigator’s post. Pia, Delfina and Onesta were walking in single file, carrying their captive on their shoulders; they’d extruded extra arms to hold him in place, but he did not appear to be struggling. The fourth machinist, Severo, was too short to join in the formation, so he walked ahead of the women as a lookout.

  The machinists dropped their burden in front of the navigators; the saboteur crouched on the stone, his face turned to the floor. He wasn’t wearing a name tag, but Yalda was almost certain that she recognized him.

  “Nino?”

  He didn’t reply. She squatted for a better look; it was him. She still remembered handing him his tag before Eusebio’s big speech.

  “Why?” she demanded, angry and perplexed. Nino had witnessed Benedetta’s crash, but he had still chosen to stay with them; she’d thought that was a sign of his commitment. “What did Acilio offer you?”

  At the mention of the name Nino’s rear eyes flickered toward her, all but confirming her guess. “Is there anyone else here working for him?” she asked.

  Nino’s reply was inaudible beneath the noise of the engines. “Speak louder,” Yalda yelled. “Who else did he recruit?”

  “I only know about myself,” Nino insisted. “If there are others, I was never told.”

  Yalda addressed the machinists. “You did a good job. You should go back to your posts now; I don’t want any feeds left unguarded.”

  “Are you sure you can control him?” Delfina asked. “He’s a fast runner. You should fetch some melding resin.”

  Melding resin? Yalda said, “We won’t let him out of this room. Please, protect your feeds.”

  When they’d gone, Yalda sat on the floor in front of Nino. “Tell me the truth,” she pleaded. “Is there anyone else? If the Peerless ends up damaged, it’s your life too.”

  “There are tools in the next chamber,” Babila announced darkly. “Frido could fetch them for us.”

  “Tools?”

  “Screwdrivers, chisels, awls,” Babila explained.

  Yalda said, “Just… let me talk to him.”

  She turned back to Nino. “Start at the beginning. If you want us to believe you, you have to tell us everything.”

  Nino kept his eyes cast down. “I lied to you,” he admitted. “I have children.”

  Yalda recalled him claiming that his co had died when he was young, but she’d never believed that; she’d thought he was fleeing from pressure to raise a family. “So why be apart from them?”

  “Gemma destroyed my farm,” he said. “I was already in debt. The Councilor said he’d pay what I owed—and pay my brother enough to look after all the children.”

  “In return for what?”

  “First, just to join you and… spy for him.” Nino’s voice faltered, though Yalda wasn’t sure if he was ashamed of his actions or merely embarrassed. “I was hoping that might be enough—that I might not have to go into the void myself. But then he gave me instructions for jamming the feeds, and said he’d double the payment to my family if the Peerless went dark within one bell of the launch.”

  “How did he know any details about the feeds?” Yalda had forgotten where Nino was meant to be working, but he certainly hadn’t been in training for a machinist’s job.

  “I don’t know,” Nino replied. “The Councilor knew more about this rocket than I did. He must have had other spies.”

  “Other spies where?” Yalda pressed him. “In the construction crew, or among the travelers?”

  “I don’t know,” Nino repeated flatly.

  “What did you use to stop the feeds?” she asked.

  “These.” He opened two pockets and took out some small rocks. “I jammed them under the emergency shutoff levers for the liberator tanks. I was told to do that for as many feeds as I could, until the machinists got word to shut down all the engines.”

  There were several such levers in each feed chamber—some of them far from the machinists’ posts. The chambers were so crowded with equipment that it would have been no great feat to enter and leave them unseen, especially while everyone was confined to their benches.

  Yalda took one of the rocks from him. It was a kind of soft powderstone, shedding a fine sand even as she handled it. Jammed under a lever, before long it would have simply crumbled and fallen away. If Nino hadn’t been caught in the act they might never have known what had really happened, and ended up convinced that the feeds themselves were at fault.

  “And then what?” she asked.

  “Nothing else,” Nino said. “If I didn’t get caught, I was meant to blend in again: just go back to my station and do my job.”

  “So after the sabotage was over, you’d be ready to pull your weight?” Yalda asked sarcastically. “Ready to be part of the team again?”

  “I never wanted to harm anyone!” Nino protested vehemently. “The Peerless was meant to drift in the void for a while—that’s all. Once the Councilor got what he wanted, why would I bear any ill will toward you?”

  “Whatever your background really is,” Yalda replied, “you’ve seen more than enough since we recruited you to know how dangerous this was. Don’t pretend that it never crossed your mind that you could have killed us all.”

  Nino tensed angrily at the accusation, but his silence stretched on too long to end in an indignant denial. “I
asked the Councilor about that,” he admitted finally. “He said if the mountain crashed into the ground, it would be a mercy.”

  “A mercy?”

  Nino looked up and met Yalda’s gaze. “He said the whole idea of a city in the void was insane. One by one, things would go wrong—things that couldn’t be fixed without help from outside. Within a generation you’d all be starving. Eating the soil. Begging for death.”

  Yalda sent a message up to the nearest construction workshop, summoning people with the skills to create a secure prison cell, but she expected it would take a couple of days for them to arrive, lugging supplies. As a stopgap she shifted the food out of the pantry that served the navigators’ post and improvised a latch for the door, using tools and spare parts from the adjacent feed chamber. The navigators would be sleeping in shifts, so there would always be at least two of them awake—and by moving the bed right next to the pantry door, it provided a barricade and allowed even the sleeper to act as a third guard.

  Babila had offered to escort Nino up through the mountain and organize his incarceration in a distant storeroom—for the sake of getting him as far away as possible from anything vulnerable to further sabotage—but Yalda preferred to have him nearby, in case she thought of something important that she’d failed to ask him about Acilio’s scheme. According to the recruitment records Nino was unschooled, but as an experienced farmer he’d been destined for the same job on the Peerless. Yalda had no reason to trust him to tell the truth about anything, but his account of his own actions struck her as plausible, even if he was probably embellishing the story or omitting details in order to portray himself in the best possible light.

  As her sense of shock and anger faded, Yalda found herself feeling a kind of battered exhilaration at the way things had actually unfolded. The Peerless had been tripped, three times, but it had kept its balance—and if the test had been unwelcome, the outcome was still worth celebrating. They had proved that the machinery on which their lives depended was every bit as resilient as they’d hoped—and they had humiliated an enemy in the bargain.