There was a jolt as the rope went taut, then they were bound together, moving in a broad circle around a common point. Yalda dragged herself along the rope a short way, then gestured to Fatima to use an airburst to get rid of some of their angular momentum. By the time they were within arms’ reach of each other, their spin was almost gone.
Fatima took hold of Yalda’s helmet and pressed it against her own. “Help me get down. Please.”
She sounded terrified, and for a moment Yalda couldn’t reply. How could she have come after her at all, if she was so afraid?
“Let me take the canister from you,” Yalda suggested gently. “Don’t release it until I’m holding it.”
Fatima had two arms wrapped around the cylinder. Yalda embraced it herself the same way, then eased it out of Fatima’s grip.
With her other hands, she rearranged the rope, forming two coils and bringing them around their bodies, then securing the connection with a series of knots. Fatima was shivering; she’d already done more than Yalda could have asked of anyone. It was her own job now to get them safely down.
“I keep thinking about Benedetta,” Fatima said. “Landing is the hardest thing.”
“This won’t be like that,” Yalda promised. “No fire, no heat, no danger—” She noticed the sunstone lamp still strapped to Fatima’s shoulder. “We won’t need that anymore.” She pulled it loose and swatted it gently away into the void; with all the jarring it had suffered already, it was a miracle it hadn’t exploded.
Yalda found her target on the horizon and opened the valve on the air cylinder a notch; the effortless kick against her arms was the most beautiful sensation she’d ever felt. She’d never know if she’d already been heading back toward the ground before Fatima reached her; she didn’t want to know.
A pinprick of light appeared on the dark rock below them. “Did you see that?” Yalda asked Fatima. She’d been hoping that she might have been delirious before—or that Fatima’s ascent might have included enough unlikely swerves for her search lamp to account for everything.
“Yes. What was it?”
“I have no idea,” Yalda lied. “Don’t worry; we’ll work it out later.”
As the mountain loomed closer, the line of worksites spread out beneath them, the most distant fading to black. Yalda made a sideways correction, steering them toward the mouth of their own tunnel. When that patch of bright rock began to grow alarmingly, she squirted air down, slowing their descent. For a pause or two she thought she might have overdone it and launched them away from the mountain again, but they were close enough now that the cues did not remain ambiguous for long. She used another quick burst to slow their horizontal motion, lest they scrape all their skin off on the rock.
As the guide rails running past the tunnel mouth rushed into view, Yalda discerned a new feature: the team had tied dozens of lengths of rope to the rails, spread out along a couple of stretches, pointing away from the rock with their free ends high above the ground. If she could steer into this soft, forgiving fence—
“Try and grab the ropes!” she urged Fatima, as they swooped toward them. “The more arms to share the jolt, the better.”
A flicker before the glorious fool-catcher came within reach, Yalda used a tiny kick from the cylinder to give them a slight upward velocity. Then she dropped the cylinder and flailed around, managing to seize one of the ropes. Fatima had gripped another one, in two places. Yalda brought all her own hands onto her rope before it went taut; the shock to her joints made her cry out in pain, but she didn’t lose hold of it.
They were a few strides above the guide rails. Yalda had been expecting to have to drag herself hand-over-hand down to the ground, but the ropes’ elastic tug had delivered a little more force than was needed to stop them, and they were actually drifting slowly toward the surface.
Fatima began humming from the shock. Yalda almost joined her, but she was afraid that if she started she’d never stop.
She said, “We’re safe. You did it, my friend, and now we’re both safe.”
18
Lavinio said, “Without gravity, I think this is the best we can do.”
Yalda bent down from the ropes that crossed the test field and examined the plants. The wheat stalks were barely two spans high.
“They’re… mature? They’re making seeds?” The tiny structures protruding from the stalks certainly resembled seed cases, but they were so small that it was hard to be sure.
“Yes, they’re mature,” Lavinio confirmed.
“But they’re a twelfth the size of normal wheat!”
“However long we keep the seedlings in the centrifuge,” Lavinio explained, “they always stop growing when we take them out—but if we raise them to this height first, they don’t die when we replant them in the fields. They don’t get any bigger, but they do form seeds of their own.”
“Wonderful.”
It was not the outcome they’d been hoping for, but Lavinio couldn’t hide his fascination. “It’s as if the maturation process is triggered directly by the cessation of growth, so long as the plants are larger than some critical size. If we really understood the mechanism, perhaps we could intervene further. But for now—”
“For now, we have the option of growing six crops a year—each with extremely low yields.” Yalda prodded one of the seed cases with a fingertip. “And these actually germinate?”
Lavinio said, “Yes—if we put them in a centrifuge, like their parents. The seedlings start out extremely stunted, but they catch up in size by about the fourth stint.”
Yalda had been expecting a clear-cut verdict, one way or the other, to force her hand. The utter failure of the centrifuged seedlings would have left her with no choice but to spin the Peerless, while a perfect fix that let them grow the old-style crops would have allowed her to declare that building the engines had been a worthwhile precaution, but actually firing them had mercifully proved to be unnecessary. “So where does this leave us?” she asked.
“It would be much more labor-intensive than ordinary farming,” Lavinio said. “And we’d need at least ten dozen centrifuges to yield the same total volume of grain as we were harvesting in a year, when we had gravity.”
Ten dozen centrifuges, running around the clock. Burning fuel, demanding maintenance. Spinning the whole mountain would eat into their sunstone reserves—but they would only need to do it once.
“It would be survivable,” Lavinio added. “Not ideal, but not completely impractical.”
Yalda thanked him, and promised a decision within the next few days.
She headed back to the summit, skimming along the stairwell’s ropes. With ordinary wheat in ordinary fields, it would be a simple matter to increase the size of the crop to feed a larger population. Having to build and run a dozen more centrifuges just to increase the yield by one tenth would change everything.
But if they went ahead and spun the Peerless, and then some wayward pebble set the slopes on fire, how much harder would it be to douse the flames when the mountain was flinging everything off into the void?
Yalda left the stairwell in the academic precinct and dragged herself down the corridor toward her office, trying not to betray her anxiety as she returned the warm greetings of passersby. Now that the tunnels were finished, the completion of the spin engines was in the hands of skilled machinists—but everyone here had been out on the slopes in the dust and danger, everyone had earned the right to think of the project as their own.
Some people flashed her looks of excitement and anticipation; some called out “Three stints to go!” If she turned around and announced that all of their work had been for nothing—and that they would now have to live on meager supplies of machine-raised, stunted wheat—she was going to need a spectacularly compelling argument to back up her decision.
Marzia was waiting outside her office. “The test rig’s ready,” she said. “Just give the word, and we’ll launch it.”
“Are you sure this is safe?”
“It will be five strolls from us when it ignites, and still moving away,” Marzia reminded her. “I don’t see how we could make it any safer without giving up the chance to observe it at all.”
Yalda accepted this, but it was hard to be relaxed about the experiment. The engines of the Peerless had failed to set the world on fire, but that had never been their purpose. Marzia’s rig was designed to ignite a mineral that had never been seen burning, except perhaps on the surface of a star.
“What if a spark comes back and hits the mountain?”
“Any debris that would be hot enough to harm us will be hot enough to burn up long before it reaches us.”
“Unless you ignite the Eternal Flame,” Yalda joked weakly.
Marzia gave an exasperated buzz. “If you’re going to start invoking those kinds of fantasies, why not throw in another twist and let us survive anyway? Then we can all head home to see our families.”
Yalda said, “Go ahead and launch the rig. Just make sure that the fire lookouts know what to expect.”
Three bells later, Yalda met Marzia in the precinct’s observation chamber. Marzia had set up two small telescopes and trained them on the rig, which from their point of view appeared almost fixed now as it drifted away from the mountain. By starlight the device was just a slender silhouette, but after Yalda had taken a peek to confirm that the instrument was aimed correctly, Marzia handed her a filter to slip into the optics. The image was about to brighten considerably.