“Now what?” asked Elthebar, the stormwarden. Navani wasn’t particularly happy to have the tall man along; he looked silly with his pointed beard and his mysterious robes. But he’d been in the map room with them, and forbidding him hadn’t seemed right when she needed every mind she could get.

“Search this area,” Navani said to the others. “See if you can find a vein of garnet on the walls. It might be small and hidden among the changing colors of the strata.”

They did as she requested. Dabbid, the mute bridgeman, started searching the floor instead of the walls—working with his sphere enclosed entirely in his hand so it gave almost no light.

“Cover up your spheres and lanterns,” Navani said to the others. The command drew expressions that ranged between confused and horrified, but Navani led the way, closing the shield on her lantern.

The others obeyed one at a time, plunging the room into darkness. Light from a distant corridor flashed red in a sequence—only with no thunder. A few people’s hands glowed softly from the spheres inside, backlighting veins and bones.

“There,” Navani said, picking out a faint twinkling on the floor near one of the walls. They clustered around it, investigating the spark of garnet light in a hidden vein of crystal.

“What is it?” Isabi asked. “What kind of spren?”

The light started moving through the vein, across the floor, then down the corridor. Navani ignored the questions, following the spark until it moved up a wall. Here it followed the curving strata into a specific room, rounding the stone and slipping through the gap between door and doorway.

Venan had keys, fortunately. Inside, they had to step over rolled rugs to find the spark of light at the rear. Navani brushed her fingers against it and found a small bulge in the wall.

A gemstone, she realized. Connected to the line of crystal. It’s embedded in here so deeply, it’s difficult to see. Seemed to be a topaz. Hadn’t there been a similar gemstone embedded into the wall of that room where they’d found the model of the tower?

Infuse the topaz, the Sibling’s voice said in her mind. You can do this without Radiants? I have seen you perform such marvels.

“I need several small topazes,” Navani said to her scholars. “No larger than three kivs each.”

Her team scrambled; they kept gemstones of all sizes on hand for their experiments, and one soon brought forth a small case of infused topazes. Navani instructed her and several others to take the gemstones in tweezers and present them to the topaz set into the wall.

An infused gemstone touched to an uninfused one could be made to lend some of its Stormlight—assuming they were the same variety, and the uninfused gemstone was much larger than the infused ones. It worked a little like a pressure differential. A large empty vessel would take Stormlight from small full vessels.

It was a slow process, especially when the gemstone you wanted to infuse was relatively small—limiting the potential size differential. She moved up next to Ulvlk and Vrandl, the two Thaylen scholars. Both were artifabrians of a very secretive guild.

“Almighty send we can make this work in time,” Navani said as thunder echoed behind them.

“So that is why you brought us,” Vrandl said. She was a short woman who preferred havahs to traditional Thaylen dress. She wore her eyebrows in tight curls. “The tower is invaded, your men are dying, and you see an opportunity to pry trade secrets from our fingers?”

“The world is ending,” Navani countered, “and our greatest advantage—this tower, with its ability to instantly move troops from one end of Roshar to the other—is threatened. Is this really the time to hoard trade secrets, Brightness?”

The two women didn’t reply.

“You’d watch it burn?” Navani said, feeling exhausted—and snappish. “You’d actually let Urithiru fall rather than share what you know? If we lose the Oathgates permanently, that’s it for the war. That’s it for your homeland.”

Again they remained silent.

“Fine,” Navani said. “I hope when you die—knowing your homeland is doomed, your families enslaved, your queen executed—you feel satisfied knowing that at least you maintained a slight market advantage.”

Navani pushed to the front of the group, where her scholars were coaxing Stormlight into the wall gem bit by bit. Often a fabrial needed to fill a certain percentage before it activated—but the more this one drew in Stormlight, the slower the drain would occur.

Footsteps scraped the stone behind her, and Navani turned to see Ulvlk—junior of the two Thaylen scholars—standing behind her. “We use sound,” she whispered. “If you can make the gemstone vibrate at a certain frequency, it will draw in Stormlight regardless of the size of gems placed next to it.”

“Frequency…” Navani said. “How did you discover this?”

“Traditions,” she whispered. “Passed down for centuries.”

“Create a vibration…” Navani said. “You use drilled holes? No … that would require Stormlight to be already infused. Tuning forks?”

“Yes,” Ulvlk explained. “We touch the tuning fork against the full gemstone, making it vibrate, then can lead a line of Stormlight out to the empty one. After that, it will siphon, like liquid.”

“Do you have the equipment here, now?” Navani asked.

“I…”

“Of course you do,” Navani said. “When I sent runners to fetch you, you thought I was going to evacuate you. You’d have grabbed anything of value in your rooms.”

The young Thaylen woman fished in her pocket, pulling out a metal tuning fork.

“You will be expelled from the guild!” Vrandl snapped from behind, angerspren pooling beneath her. “This is a ploy!”

“It’s no ploy,” Navani assured the nervous young woman. “Honestly, we were close to a breakthrough using the weapons the Fused have—which are able to drain Stormlight out of a person. All you’ve done here is potentially save this tower from invaders.”

Navani tried the method, hitting the tuning fork, then touching one of the infused gemstones. Indeed, as she pulled it away from the stone and toward the gemstone on the wall, it trailed a small stream of Stormlight. Like how Light behaved when a Radiant was sucking it in.

That did the trick, infusing the wall gemstone in seconds. The Sibling had explained what was coming, but Navani still jumped when—upon being infused—the fabrial made the entire wall shake.

It parted at the center; it had been a hidden door all along—locked by a fabrial that in the old days probably only a Radiant could have activated. They quickly uncovered their lanterns and spheres, revealing a small circular chamber with a pedestal in the center. Set into that was a large sapphire, uninfused.

“Quickly,” Navani said to the others, “let’s get to work.”

* * *

Kaladin slung his pack over his shoulder, then slipped out of the room of another frightened family. This one, like those before, had asked him for news, for information, for promises. Was it going to be all right? Would the other Radiants rise as he had? When would the Bondsmith return?

He wished he had answers. He felt so blind. He’d grown accustomed to being in the thick of everything important—privy to not only the plans of important people, but their worries and their fears as well.