Dema brought a sheet of wet cloth to the fan test.
“If it doesn’t move this,” she said, “I won’t let you tell the clinic it works.”
Iven held the cloth by one corner. Water ran from the other into the channel beside the maintenance platform. “If it moves that, we can use it to pull the carts.”
“Good. The carts are waiting too.”
The fan drum sat on blocks outside its housing. The new blade had been shaped and tempered at the forge, its mounting holes placed farther from the weakened edge than the original. Iven had checked the dimensions again that morning. Jem and Vela had checked them after him, partly because they did not trust him and mostly because they trusted a fan less when it had to spin fast near people’s heads.
Neri’s temporary bridge support had held overnight. A second prop now stood beneath the bent bracket, and a rope barrier marked the edge of the broken span. The service gate remained chained. Kesh’s watch had heard movement in the upper duct but had seen no vent-hooks since the previous afternoon.
Sera arrived with a basket of dry bandages and a list of rooms whose filters needed fresh cloth. She set both on the platform.
“Can you give Dema the first batch when it dries?” she asked.
“Of course,” Dema said. “Will you stop checking the list while we’re working?”
“No.”
“Then at least move it out of the way of the grease.”
Sera placed it on a clean crate. Iven had promised to let other people lift the drum. He kept the promise by directing the work from a position where he could see the shaft and both bearings. Jem and two workers took the weight on a physical hoist. Vela guided the far end into its housing. Neri watched the clearance between the drum and the casing.
“Left a little,” Neri said.
Jem moved it left.
“Your left.”
“That’s where I moved it.”
“Then the housing moved right.”
They adjusted it until the shaft rested in the new sleeve. Iven inserted the retaining collar, tightened its bolts, and turned the drum by hand. The blades passed the casing with a narrow, even gap. No edge scraped.
“New blade,” Vela said.
He lifted it from the cloth where the smith had wrapped it. The curved plate was heavier than the others by a small amount. They had accounted for that by adding a counterweight to the opposite side of the drum. Iven checked the fastenings again before fitting the blade.
The first bolt entered cleanly. The second stopped short. He backed it out and found a trace of forge scale in the hole. Jem cleared it with a brush. The bolt then seated without force.
“Will you mark them?” Dema asked.
Iven drew a line across each bolt head and the blade’s mounting plate. “If they move, the marks separate.”
“Good. I can see those from the access panel.”
“You should check them after the first hour, then after the full shift,” Vela said.
“I will. You can write it on the wall if you think I’ll forget.”
Vela found a piece of chalk. Dema watched her write, then added a line beneath it: If the fan makes a noise like a dying goat, stop it.
“That’s not a technical description,” Vela said.
“It’s the one my workers will remember.”
They closed the housing and opened the lower duct. The channel had been cleared the previous day. Kesh’s crew had placed a screen over the broken upper seam, leaving the other opening free so the vent-hooks could leave without passing through the fan. Kesh had watched the route at dawn and seen no animal enter.
“Does that mean they’re gone?” Brin asked.
“It means I didn’t see them.”
“That’s becoming a popular answer.”
“It’s cheaper than being wrong.”
Vela opened the drive line. The fan began to turn slowly, then stopped with a low scrape.
Everyone waited.
“Again,” Iven said.
Vela closed the line, allowed the pressure to settle, and opened it once more. The drum turned through half a rotation. The scrape came at the same point.
Iven opened the access panel and looked inside. One of the old blades had shifted when the new mounting was tightened. Its tip now touched a raised seam in the casing.
“That’s mine,” he said.
“You didn’t make the seam,” Jem replied.
“I tightened the blade without checking the full circle afterward.”
Neri handed him the spanner. “Then check it now.”
He loosened the blade, adjusted its angle, and turned the drum by hand through two complete rotations. It cleared the seam each time. Jem checked the opposite side. Vela tested the shaft’s end play. When the panel was closed again, Iven asked Dema to stand with the wet cloth at the duct outlet.
“Not directly in front,” he said. “If anything comes out, I want it to hit the wall.”
“Anything?”
“Loose dust. A forgotten tool. My reputation.”
“Your reputation has survived worse.”
Vela opened the line.
The drum turned. This time it continued past the old point of contact. The sound deepened as the blades gathered speed, a steady rush under the metal casing. Air came through the lower duct in a concentrated stream. Dema’s cloth lifted, twisted, and pulled against her hands.
“It moves,” she called.
“Does it dry?”
“That takes longer than a breath.”
Iven stood beside the housing, listening for a knock or uneven scrape. The new sleeve stayed cool under his hand. The marks on the blade bolts remained aligned. The air stream strengthened until dust rose from the floor and hurried toward the open channel.
The graft along his left forearm warmed. The pattern settled gradually, more like the rhythm of a wheel than the sudden impact of a piston: a rotating surface pushing air in a chosen direction, bounded by the energy and space available to it. He held the feeling without trying to use it. The fan still needed its full test.
Vela adjusted the drive. The drum ran at its working speed for several minutes. Dema took the wet cloth to the outlet and hung it where the stream could reach it. The cloth flapped against its support, then began to settle as water left the surface.
“Now?” Iven asked.
“Now it works.”
He smiled. The new pattern remained distinct beneath his skin. He had earned it through the blade, bearing, alignment, and test, but the machine did not become less useful because he had learned from it. The air continued toward the drying room.
A shout came from the upper stair.
Kesh ran down with her pole. “The smaller one is at the screen. It has something caught around its limb.”
“Is it trying to get through the fan?” Vela asked.
“It’s trying to pull the screen away.”
The screen protected both the machine and anything on the other side from the blades. If the animal tore it loose, the fan could draw it into the drum or send loose metal into the housing.
“Stop the drive,” Iven said.
Vela closed the line. The drum slowed but did not stop immediately. Iven waited until it had nearly settled. He considered holding the accessible brake tooth, but the ratchet was not seated. Sheltered beside the housing, he released plate and brought ratchet forward; then he applied the hold while Vela secured the mechanical brake.
Kesh led them to the upper seam. The young vent-hook clung to the screen, its dark body pressed against the duct. A length of wire had wrapped around one forelimb and caught on the mesh. It pulled repeatedly, bending the screen outward.
“It’s the one I hit,” Iven said. A cracked plate showed at its shoulder.
“It may remember you,” Kesh replied.
“Does it have to?”
“It doesn’t have to like you.”
The animal turned toward their lamps. Its feelers spread. Behind it, the duct narrowed into a passage too small for a person to enter.
“If we cut the wire, will it attack?” Vela asked.
“It might. If we leave it, it will tear the screen.” Kesh looked at Iven. “Can you hold the limb without putting your hand beside it?”
He had ratchet, piston, and bell seated after the change at the brake. The new fan pattern was in his library but not ready. A physical pole could hold the limb against the mesh while Kesh cut the wire. He did not need to test a new ability on an animal whose reaction he could not predict.
Jem passed him a padded bar. Iven set it against the creature’s hooked limb and pressed it gently toward the screen. The animal pulled. He used the ratchet pattern at the bar’s contact point, resisting the movement in one direction while allowing Kesh to shift the wire.
“Now,” he said.
Kesh cut the wire. The creature jerked free, struck the padded bar once, and backed into the duct. It paused at the bend, feelers moving, then vanished into the smaller passage.
Vela examined the screen. Two wires were bent, but the frame remained secure. She replaced the damaged section with a spare piece while Iven held the bar against the frame. They checked the bolts, cleared the cut wire, and returned to the fan.
The second run held. The drum turned smoothly. Dema’s cloth moved in the stream, and the drying room’s upper vent carried damp air away. Workers began bringing the first usable batch toward the clinic.
Iven waited until the crew had cleared the outlet, then stepped into the open space beside the housing. Sheltered beside the housing, he released ratchet and seated the new fan pattern; he also reseated plate in place of piston. Plate and bell occupied the other channels. He aimed his left hand toward a loose strip of cloth tied to a post and released a small burst.
Air pushed outward in a narrow cone. The strip snapped away from him, then fell back. He tried again with less force. Dust lifted from the floor and moved toward the channel.
“Can you move a person?” Jem asked.
“Let’s find out with a person who agrees.”
Jem stepped onto a dry patch and planted his boots. Iven warned him, then sent a stronger gust toward his chest. Jem leaned back, slid half a step, and caught himself.
“Again,” he said.
Neri folded her arms. “Why?”
“Because I want to know whether I can stay up.”
“You did.”
“Barely.”
Iven sent a second burst from a different angle. Jem shifted his footing before it arrived and stayed in place. The effect was useful, not irresistible. A person who saw it coming could brace, and a heavier object would move less.
Dema held up the wet cloth. “Can you dry this faster?”
“Not without spending more charge than the fan uses from its drive.”
“Then let the machine do it.”
He liked the answer. The imprint gave him a way to move air when no machine was available. The repaired fan could do its ordinary work for as long as its drive and maintenance allowed. Neither had to replace the other.
They carried the first dry-enough cloth to the clinic. Sera inspected it and allowed half into the clean store. The rest returned to Dema for another hour. No one celebrated the difference between half and all, but the shelves were less empty when they left.
At the bridge above the lower lane, Neri checked the far bolts again. A cart crossed with a load of timber, followed at a distance by two workers. The marks remained aligned. Cage Seven moved along its guide nearby, its replacement wheel turning without a scrape.
Tavin met them with a folded message. “The freight captain has our questions for the Sill. He’ll deliver them when the next transfer reaches the station.”
“How long?” Iven asked.
“A few days if the weather holds. Longer if it doesn’t.”
“Can we go with the freight?”
“Not yet. The next crossing is for supplies, and the station needs notice before a larger party arrives.”
Iven looked beyond the saddle toward the distant escarpment. He could not see the Sill from here. He could see the direction in which the route ran: a line of dark ground, intermittent water, and the distant shapes of other moving cities.
Asa came down the lane carrying a basket of bowls. “The people from the washhouse have a room for the week. The mason says the passage can reopen after the upper wall is shored.”
“Who pays for it?” Neri asked.
“The owner and the relief fund. The family doesn’t.”
Iven took the basket from her. She did not object, though she kept one hand on it until he had a good grip.
At the kitchen, Vale was serving the evening meal. Brin announced the fan’s success before anyone asked. Dema corrected him when he said it had dried every piece of cloth in an hour. Kesh described the young vent-hook’s retreat, and Vale asked whether anyone had checked the kitchen’s own vent screen.
“I’ll look after supper,” Iven said.
“You’ll eat first,” Vale replied.
He sat. The new fan pattern rested beside the others in his library, ready to be seated when he needed it. It did not make the clinic’s shortages vanish or bring an answer from the Sill faster. It gave him another way to act, earned by a machine that was now working for the people who depended on it.
Dema’s workers brought the remaining cloth through the door while he ate. They hung it on a line above the stove, where the last dampness could leave without carrying soot into the fibers. Vale handed each of them a bowl. No one had to be told to sit down.