It’s a personal lift, meant to levitate you up and down long distances. To help you travel the height of the tower.

“Interesting,” he said, glancing at the device laid out on the stone bench. “Though, I’m not one for technology, Brightness. Pardon, but I barely know how to turn on a heating fabrial.”

You’ll need to learn quickly then, Navani said. As you’ll need to replace the rubies in the fabrial with the Voidspren ones from the spanreeds you stole. We’ll need all twelve pairs. Do you see a map in with the device?

“Just a moment,” he said, digging in the sack and pulling out a small folded map. It led to a place on the twentieth floor, judging by the glyphs. “I’ve got it. I should be able to reach this place. The enemy isn’t guarding the upper floors.”

Excellent. There are weights in a shaft up there where you’ll need to install the other halves of those rubies. A mechanism on the fabrial bracer will drop one of those weights, and that force will transfer through the bracer. You’ll be pulled in whatever direction you’ve pointed the device.

“By my arm?” Kaladin asked. “That doesn’t sound comfortable.”

It isn’t. My engineer has been trying to fix that. There is a strap that winds around your arm and braces against your shoulder, which he thinks might help.

“All right…” he said. It was something to do, at least.

But fabrials? He’d always considered them toys for rich people. Though he supposed that was becoming less and less the case. Breeding projects were creating livestock with larger and larger ruby gemhearts, and fabrial creation methods were spreading. It seemed every third room had a heating fabrial these days, and spanreeds were cheap enough that even the enlisted men could afford to pay to send messages via one.

Navani coached him through replacing the rubies. Fortunately, the case of spanreeds he’d stolen included a few small tools for undoing casings. It wasn’t any more difficult than replacing the buckles on a leather jerkin.

Once it was done, he and Syl ventured out, sneaking up nine floors. He didn’t use any Stormlight; he didn’t have enough to waste. Besides, it felt good to work his body.

On the twentieth floor, the garnet light led him to the location the map had described. Inside he found the weights and the shaft, and Navani walked him through installing the matching rubies. He began to grasp how the device worked. The big weights were more than heavy enough to lift a man. Five of the rubies in his fabrial were connected to these weights, binding them together.

The other seven rubies were used to activate and control the weights. The intricate system of pulleys and mechanisms was far more complex than he could understand, but essentially it allowed him to switch to a different weight when one had dropped all the way. He could also slow the weight’s fall or stop it completely, modulating how quickly he was being pulled.

Each weight should be able to pull you hundreds of feet before running out, Navani said via a garnet vein on the wall. These shafts plunge all the way down to the aquifers at the base of the mountain. That means you should be able to soar all the way up from the ground floor to the top of the tower using one weight.

The bad news is that once all five weights have fallen, the device will be useless until you rewind them. There is a winch in the corner; it’s an arduous process, I’m afraid.

“That’s annoying,” Kaladin said.

Yes, it is mildly inconvenient that we have to wind a crank to experience the wonder of making a human being safely levitate hundreds of feet in the air.

“Pardon, Brightness, but I can usually do it with far less trouble.”

Which is meaningless right now, isn’t it?

“I suppose it is,” he said. He looked at the fabrial, now attached to his left arm, with the straps winding around all the way to his shoulder. It was a little constrictive, but otherwise fit quite well. “So, I point it where I want to go, activate it, and I’ll get pulled that way?”

Yes. But we made the device so that it won’t move if you let go—it was too dangerous otherwise. See the pressure spring across your palm? Ease off that, and the brake on the line will activate. Do you see?

“Yes,” Kaladin said, making a fist around the bar. It had a separate metal portion wrapped around it on one side, with a spring underneath. So the harder he squeezed, the faster the device would pull him. If he let go completely, he’d stop in place.

There are two steps to the fabrial’s use. First, you have to turn the device on—conjoining the rubies. The switch you can move with your thumb? That’s for this purpose. Once you flip it, your arm will be locked into its current orientation, and won’t be able to move the bracer in any direction except forward.

The second step is to start dropping a weight. If a weight falls all the way, swap to the next one using the dial on the back of your wrist. You see it?

“I do,” he said.

Once you stop, you’ll remain hanging until you disengage the device. But so long as you have another weight that hasn’t run out, you can turn the dial to that one, then continue moving upward. Or if you’re bold enough, you can disengage the device and fall for a second while you point it another direction, then engage it again and set it to pull you that way instead.

“That sounds dangerous,” Kaladin said. “If I’m up high in the air, and need to get over to a balcony or something, I have to drop into free fall for a bit to reset the direction of the device so it can pull me laterally instead of up and down?”

Yes, unfortunately. The engineer who created this has grand and lofty ideas—but not much practical sense. But it’s better than nothing, Highmarshal. And it’s the best I can do for you right now.

Kaladin took a deep breath. “Understood. I’m sorry if I sounded ungrateful, Brightness. It’s been a rough few days. I’m glad for the help. I’ll familiarize myself with it.”

Excellent. You shouldn’t have to worry about the Voidlight in the gemstones running out through practice—conjoined rubies don’t use much energy to maintain their connection. But they will run out naturally, over time. We’ll have to figure out what to do about that when it happens.

For now, I’m hoping the Sibling will soon trust me enough to tell me where to find the remaining nodes. Once I have that information, I can devise a plan to protect them, perhaps by distracting the enemy’s search toward a different region of the tower. It’s vital that you keep that shield in place as long as possible, to give me time to figure out what is wrong with the Light in the tower and its defenses.

“Any movement there?” Kaladin asked.

No, but I’m currently focused on filling holes in my understanding. Once I have the proper fundamentals on Stormlight and Voidlight, I hope I’ll make more rapid progress.

“Understood,” Kaladin said. “I’ll contact you again in a few hours, if you can make time, to discuss my experience with this device.”

Thank you.

He stepped away from the wall. Syl stood in the air beside him, inspecting the fabrial.

“So?” Kaladin asked her. “What do you think?”

“I think you’re going to look extremely silly using it. I can’t wait.”

He walked out to a nearby hallway. Up here on the twentieth floor, he should be safe practicing in the open—assuming he stayed away from the atrium. He walked the length of the hallway, setting out amethysts to light the way. Then he stood at one end, looking down the line of lights. The fabrial left his fingers free, but that bar in the center of his hand would interfere with fighting. He’d have to one-hand his spear, as if he were fighting with a shield.