Incandescence

introductions; the light-bearer was called Lud, and the others were Jos, Rud, Cot and Sad.

The light that emerged from the machine on Lud’s back was weak, rendering the group sketchily. Their bodies were merely hinted at by a glimmer of surfaces, as if their carapaces had turned to metal. Seeing your companions’ beating hearts was not the point, though; this modest light would still be enough to allow you to spot obstacles and walk through the darkness with confidence.

“Where are you headed?” Ruz asked politely. Roi was sure that he was twice as eager as she was to hear how the light machine worked, but it would be discourteous to raise the matter immediately.

“We have no destination yet,” Jos replied. “We want to know what’s happening to the Splinter, so we’ve left our teams to search for answers.”

Roi could hardly believe what she was hearing. They’d left their teams? How? Had the Jolt shaken them free, like the rubble it had torn from the solid walls?

She said, “We have some ideas about what’s happening to the Splinter. We believe something has pushed it, and now it’s falling back and forth, in and out of the Incandescence.”

Lud said, “Falling back and forth?”

“If you throw something shomal from the Null Line,” Ruz explained, “it will reach a certain distance, fall back to the Null Line, go past it some way junub, fall back again, and so on. We think the Incandescence ends if you go far enough shomal or junub, and that’s why the light comes and goes.”

The group talked this over among themselves, then asked to hear more. Zak remained quiet, which usually meant that he was tired or in pain, so Roi explained his idea of the Splinter orbiting the Hub, and the experiments in the Null Chamber that seemed to support it.

While they were talking the light from the machine faded, and its whirring sound died away. But the walls were already beginning to brighten, and soon Roi had a normal view of everyone. They had a small cart with them, full of metal parts.

Cot climbed on to Lud’s back and began turning a handle attached to the machine. Ruz could no longer contain himself. “It’s spring driven, isn’t it?”

“Of course,” Lud said. “Trying to crank it smoothly and walking at the same time would be impossible.”

“But what makes the light?” Ruz’s tone was drenched with such longing that he might have been a starving child begging for food.

Lud chirped with amusement. “Just two rough surfaces scraped over each other, under pressure. Rough enough to make a disturbance, but not so rough that they’ll stick.”

Jos added, “I found the effect completely by luck. I was grinding plants into a powder between two stones, and I grew tired of stopping work every time it grew dark. When I ground stone against stone with nothing between them, a faint light seemed to come from the point of contact. At first I thought I was just going mad from the darkness, but the more effort I applied, and the less of the mush there was to smooth the stones, the stronger the light became.”

Roi said, “So you’ve left your old teams now? You’ve formed a new one, and you’re looking for recruits?”

“Not exactly,” Cot replied, working briskly to ensure that the spring was fully wound before the darkness returned. “We still don’t know what’s the best thing to do. We’ll form a team if that’s necessary, but we’re willing to join an existing one if they can make a good case that they know what’s going on and that they’re doing something useful about it.”

Every time Roi thought she could no longer be shocked, these people outdid themselves. It had taken a great struggle for her to tear herself free of her work team to join Zak. On that first journey to the Null Chamber she had never been able to admit her intentions, even to herself. Now here were five people roaming the Splinter, challenging every passing stranger to make a reasoned bid for their labor, as if the whole idea of recruitment had been turned inside out.

Zak spoke softly. “Some people are trying to build a tunnel that will change the way the wind pushes on the Splinter. If they succeed, they hope it will carry us to safety. I’m sure they could use your skills.”

Lud said, “I can make no promises, but we’d be happy to talk to them, to hear their case.”

Ruz said, “We can draw you a map, give you directions.”

“You’re not going there yourself?” asked Sad.

“We have another task.” Roi explained about the crack in the wall, and the observations that they hoped would clarify both the Splinter’s ordinary motion and the nature of the Jolt.

The idea struck a chord with the light-makers, and they seemed torn between joining Zak’s expedition and heading for the sardside and the tunnel-makers. Zak, however, explained that he would be making the observations alone and that his two assistants were all that he needed.

Cot said, “Then at least take this with you to help you on your way.” He opened the cart and produced a second light machine. “We brought two spares, and plenty of parts. If you take this one, we will still have no trouble reaching the sardside.”

Zak said, “Thank you.” Roi would have preferred an extra body or two to help pull Zak’s cart; this was more weight to carry, and now they’d have no excuse to rest when darkness came. Still, at least this way they could choose their own pace.

Roi drew a map for the light-makers showing the way to Bard’s team, and the two groups parted. Ruz agreed to carry the light machine on his back; he took the rear harness so as not to obstruct Roi’s view ahead.

They toiled on toward the junub edge, resting as they wished and using the machine to enable them to travel through the darkness. At first Roi found the strange, shallow illumination it cast disorienting, but after a dozen cycles she was accustomed to it, her mind switching easily between the two ways of seeing.

It was hard work winding the spring, though. “I want you to improve on the design,” she told Ruz.

“In what way?”

“I want a version that works unattended, filling itself with light when there’s light to spare, then releasing it in the darkness.”

As they approached the edge the tunnels became increasingly strewn with rubble and the walls ever more fractured. Some of this might have been due to the Jolt, but Roi had heard descriptions of the area that long predated that event. It was easy to believe in a crack in the outer wall here, if not so easy to reach it.

Ruz, who had been timing the lengths of each stretch of light and darkness, reported that he’d finally started to detect a small asymmetry between successive times spent in the dark. Now that they were a significant distance away from the Null Line, when the Splinter moved junub of the Incandescence the darkness came earlier, and lasted longer, than when it moved shomal. Roi had already noticed a difference in the way the light penetrated the rocks, with the onset of brightness coming faster when it started from above than from below, but every sign that confirmed their guesses about the Splinter’s motion through the Incandescence was important. Apart from anything else, they would be relying on the rock of the Splinter to protect Zak from any dangerous emanations; they did not want to misidentify the phases of the cycle and send him out in the wrong period of darkness, to find the Incandescence looming directly above him.

Shifting enough rubble to allow them to steer the cart through the tunnel became an impossible task. Roi helped Zak pack the instruments into his cavities, then had him climb on to her back. According to Zak’s map they did not have far to go, but the map contained no annotations about the ease of travel along the tunnels it portrayed—let alone an up-to-date account that included the damage wrought by the Jolt.

Roi noticed a slight thickening in the sparse vegetation on the walls before she felt the faint hint of a wind, rising and dying with the light. This close to the Calm, that could only mean that the feeble wind had almost no rock to penetrate. She moved ahead cautiously, afraid that they might all be caught by surprise with no roof above them, but as they approached the intersection marked on the map as lying directly beneath the crack, the onset of light brought no blinding revelation. If anything, this place seemed less bright than the garm-sharq edge.

Still, the vegetation on the roof was the thickest Roi had seen since they’d set out from the Null Chamber. She set Zak down and clambered up the wall to explore it. She hadn’t walked upside down in weight like this for a long time, and the encrusted surface didn’t make it any easier.

She probed the surface gently with her claws. “The rock feels strong,” she reported. “No gaps, no cracks.”

Ruz said, “Maybe the vegetation’s repaired it.”

“All my maps are too old,” Zak lamented. “We should have brought tools to cut our way out.”

“Tools, and a very large work team,” Roi suggested. She’d heard it said that the outer wall was at least a