Greg Egan - The Clockwork Rocket

Strapped to her bench in the navigators’ post, Yalda counted down the pauses. It had always been Frido or Babila doing the honors before, but she’d taken the role for herself this time, knowing it would be her last chance.

“Three. Two. One.”

The anticlimax that followed was welcome; any sudden, perceptible change would have meant that something had gone horribly wrong. The clock advanced another two lapses before Yalda noticed anything at all—and even then she had her doubts; the hint of dizziness, of balance gone awry, could as easily have been nothing but anticipation. The machinists were tapering off the flow of liberator in an excruciatingly protracted manner; it would take a full chime for the engines to shut down completely.

“Can you hear that?” Frido asked.

“Hear what?” Babila raised her head to listen.

Yalda said, “The rock.” Over the hammering of the engines, she could make out a low creaking sound coming through the ceiling. The mountain had lost only a fraction of its weight, but it was already beginning to rearrange itself, stretching out beneath the diminishing load. That was not a bad sign; better that it start adjusting now than save up the changes for a sharp transition later that released all its energy at once.

Four lapses into the shutdown, Yalda could have sworn that the skin on her back was growing numb—and knowing the true reason that she was starting to register less pressure did nothing to make the illusion less compelling. At seven lapses her dwindling weight began triggering flashes of panic, in which she was convinced—for a moment or two—that the legs of the bench had given way beneath her. The engines were producing a strange, soft patter now; the rock above had fallen silent. For the first time since the launch, she could hear the ticking of the clock from across the room.

Babila turned and vomited up her last meal, thoughtfully depositing it out of sight of her companions—though the floor itself might not hold the mess down much longer. With no hope of reconciling the room’s apparent steadiness with the alarming sense that everything was slipping, Yalda closed her eyes. She found herself visualizing the Peerless from a distance, a dark cone against the color trails. But in this fanciful vision the middle third of the mountain had turned as soft as resin, and she watched in horrified fascination as it stretched out into a narrow tube, then snapped—

She braced for the impact that must have followed the same plummeting sensation for every one of her ancestors who’d had the misfortune to experience it. That the crash never came was no surprise, but nor was it a relief; the threat of impending damage refused to be dispelled.

Yalda lay on her bench humming softly, waiting for something to change. Finally, she grew sufficiently inured to the sense of dread to open her eyes and look around. Frido had removed most of his straps and was sitting up; Yalda did the same, and felt no worse for it. In fact, the actions were reassuring, proving that she still had control over her body.

Half a dozen ropes had been strung across the room at shoulder height. Frido finished unstrapping himself and reached up to take hold of the nearest of them. At first he tried to walk across the floor, using the rope as an aid, but his feet kept slipping on the stone. Then he changed his approach, curling his body up and gripping the rope with his feet as well, forming them into a second pair of hands. After a few unsteady moments, he mastered the technique and scurried along the rope, hand over hand, as far as the wall. Then he swung onto a second rope that was fastened to the stone beside him, and set off in a new direction.

Babila watched him, stupefied. “I’m not doing that for the rest of my life,” she moaned. “You can send me home right now.”

Yalda removed the strap from around her waist and took hold of the nearest rope. Following Frido’s example, she re-formed her feet and tried to raise them, but then she found herself tumbling slowly in mid-air, still clinging to the rope with a single hand but unable to seize it with any other appendage.

“Hunch up, you fool!” Babila suggested irritably; in her state of nausea even Yalda’s clumsiness was a personal affront. But it was good advice; Yalda had no control over her body’s orientation, but she could still bring all four hands together at the point where she held the rope. From there, she slid them along it, spacing them out more comfortably. She looked across the room to study Frido’s technique—he was never taking more than one hand off the rope at a time—then she began tentatively pulling herself along.

She was fine at first, until her sense of the vertical flipped and the cozy illusion that she was hanging down from a horizontal rope was replaced by the equally false conviction that she was perched above it, precariously balanced, certain to tumble over at any moment. She closed her eyes and pictured herself ascending instead: climbing up a vertical rope. When she opened her eyes and started moving again, her chosen illusion persisted; the small forces on her body as she dragged it along the rope were oriented in the right direction to reinforce the idea.

After practicing for a while she became reasonably proficient, but it was disconcerting to be so dependent on the ropes. If one of them snapped, installing a replacement would not be easy; it was clear now that they’d underestimated the number of handles needed on the walls to ensure that a chamber like this remained navigable, come what may. And if threading a new rope into place was a major task, any kind of construction work would be impossible.

Frido left the navigators’ post, dragging himself through the doorway to see how the neighboring machinists were faring. Babila was still sitting on her bench looking miserable. Yalda approached her.

“Try the ropes,” she said. “I’ll stay close to you.”

“I can’t do it,” Babila declared.

“You can’t hurt yourself. You can’t fall.”

“What if I get stranded?” Babila retorted. “Drifting in mid-air?”

It wasn’t an entirely ridiculous objection; the chamber was high enough that someone really could end up out of reach of anything solid—let alone anything they could actually grasp.

“Even if you let go of the rope accidentally,” Yalda pointed out, “you won’t drift away from it very quickly. You’ll always have time to grab hold of it again. And I’ll stay in front of you, I’ll make sure you’re all right.”

Babila wasn’t happy, but she reached up with one hand and grabbed the rope beside her, released the strap around her waist, then refashioned her obsolete feet and curled her body up so she could grip the rope in four places.

“We’re all animals now,” she declared forlornly. “I feel like an arborine.”

“Is that so bad?” Yalda wondered. “We’re going to have to re-learn everything we do, but if we’ve done something similar before, in the forests, that can only help.”

“And which zero-gravity forests were they?” Babila began pulling herself along the rope with surprising speed.

Yalda backed away from her hastily. “None in the past,” she said, “though it might be interesting to see how they deal with it now. We might learn something from all of the animals.”

“They won’t know what hit them,” Babila predicted gloomily. “They’ll cope much worse than we do.”

“Maybe.”

For all her reticence, Babila proved to be quite agile. Yalda suspected that most of her pessimism was just the nausea talking, and that both would wear off soon enough.

“A part of me keeps thinking that this is temporary,” Yalda admitted, clinging to the rope near the center of the room; the chamber now seemed to her like a disk-shaped space standing up on one edge. “As if it’s a trick that’s all down to some clever new way of using the engines, and if we get bored with it we can always just stop.”