What water takes away

The third branch ended on a narrow duct, beyond which a stream of black water flowed between two walls. It did not appear on any recent map.

Zaelyra knelt on the edge. "The current comes from the east. It must join the basin under the forges district."

Rhylor observed the water. "Or a pit."

The water had tiny shiny splinters. Zaelyra collected one from a bottle and placed it against the light of her lamp. It was not ore, but a transparent scale, very thin.

"There are fish in the pool," she says.

"Or someone is transporting it."

She put away the bottle without arguing. The detail did not establish a route; it only indicated that the water was not stagnant. The current could connect a tank to an inhabited basin.

Rhylor knelt down and deposited some dust on the water. The grains drifted, then disappeared into a crack under the ledge.

"This is where you have to fix the rope," he says.

Zaelyra handed him the pitch. "You saw it right away."

"I've already fixed a rope in the wrong place."

"What happened?"

"Someone crossed. The rope, on the other hand, remained."

He did not add who had crossed or why the rope had given way. Zaelyra planted the pitch higher, in the place it indicated, and tested the grip of all his weight before engaging.

"You let me do it? She asked.

"I'll check."

"It's not the same thing."

"No. But it's a start."

Zaelyra fixed a ribbon of paper on a rod and held it above the net. The paper leaned eastwards, then straightened up. The air current was going in the other direction. Two paths crossed under the stone.

"The water goes down to the basin. The air comes from a lower gallery."

"Or the air rises through the cistern."

"I can check with a thread."

Rhylor handed him a reel. She knotted a strand on a flat stone and let it drift. The wire stretched, vibrated, then stopped against a ring hidden under the surface.

"There is a passage below," she says.

"There's a ring underneath. Do not turn one into the other until you have checked."

He was right. Zaelyra stretched the strand until she felt the resistance of the ring, then knotted it to a roughness of the cornice. The flat stone remained under the surface, held against the metal. On the map, she noted two hypotheses, with a clearly visible question mark. She hated signs of uncertainty. That was probably why she forgot them so often.

Before engaging on the cornice, they planted two pitons several steps apart and stretched a safety rope between them. They hung their harnesses on it, with enough slack to move forward without pulling each other. Rhylor tested each piton separately. Both bit in the same strip of rock; the surface, however, showed no cracks. They advanced to the cistern. Halfway, they discovered a cut in the wall, at shoulder height. Fibers were stuck there: a rope had rubbed there recently.

"How long? Zaelyra asked.

Rhylor pinched one of the fibers. "A few days. Maybe less."

"Someone is still using the boat."

"Someone used it. It's not the same."

She looked at the black water. "You really don't want to conclude anything."

"I want to avoid concluding instead of evidence."

"And if we wait for the evidence, people can disappear."

"That's why we're moving forward. That's not why we invent."

Zaelyra folded the map in half, then reopened it on the page where she had noted the first measurements. The ink was clean, the lines straight. Nothing said that the ground was shaking or that the light had changed.

"The House's reports do not keep the assumptions," she says. "Only the conclusions."

"The reports are made to decide where to send the guards. Not to tell what people ignored."

"Then they forget how wrong they were."

"People are wrong even when they remember. Rhylor checked the pitch. "But a good survey leaves enough room for the next one to doubt."

She added a pencil mark on the edge of the page, without inking it. Next to it, she wrote the direction of the current, the angle of the cornice and the difference between the displacement of the water and that of the air. Her statement looked less like an order and more like a conversation with the person who would come after her.

"You really don't want to give a simple answer," she says.

"Simple answers are easy to carry. That's why we sell them so expensive."

"And you, what do you sell?"

"Time. When I have some."

She wondered how much time he had left, and since when he knew.

They resumed their progress towards the tank, held by the safety rope. The stone was smooth, polished by centuries of runoff. After about twenty steps, the gallery expands around a low cistern. Someone had fixed rings in the wall. Below, a flat boat was overturned against the rock.

"A road of passage," says Zaelyra.

"A road that should not appear on your report."

"You ask me to falsify the statement?"

"I ask you to choose what you put in danger."

She turned to him. "If this way is used to get people out, why is the House hiding it?"

"Maybe the House is not the only one hiding it."

A sudden thrust lifted the flat stone and stretched the thread. Three metal blows resounded under the water: the ring had just hit the wall. The current swelled and the cistern vibrated. The tremor ran into the cornice. A crack opened under Zaelyra's boot and the edge collapsed. The first piton was torn off. Rhylor pulled on the safety rope and grabbed his harness; the tension passed to the second, but the crack crossed the entire rock strip. He in turn ceeded. Both slid towards the ledge.

The lamp fell into the water and went out.

In the dark, Zaelyra felt her hand slide. Another hand grabbed his sleeve from the cornice. It wasn't Rhylor.

"Don't pull on the arm," says a familiar voice. "The stone is crumbling. Give me the rope."

Nym Varr stood above them, a bag of tools on his shoulder. A fine rope surrounded his shoulder.

"You were supposed to be in the annex," said Zaelyra.

"I was there. Then your sister had the good idea to leave a door open."

"Did Vhaelyn let you go?"

"She left the door open. My tools were in the hallway. She was looking at the stairs when I took them back."

"Did she see you?"

"Yes. She didn't sound the alarm. We didn't specify what came next."

Nym fixed his rope to a ring deeply sealed in the wall. He shot it once, then a second, listening to the metal. "Rhylor, keep your harness on. Zaelyra, pass your arm in the loop that I go down. Don't try to grab the stone: it goes under your fingers."

The buckle brushed his shoulder and slipped. She took it back with her free wrist. Rhylor kept one hand on his harness; with the other, he spread a stone that was detached above them. Nym stretched the rope until it carries Zaelyra's weight.

"Now, push against the wall."

His boot scraped the basalt. The first grip rested, but the rope held it. Rhylor and Nym slowly pulled it up, without tearing off what was left of the ledge. Once on the cornice, she rolled flat on her stomach and cleared the passage.

Nym handed him a hooded lamp. For Rhylor, he added a knot of friction to the rope and lowered a second loop.

"The first piton gave way. The second too, "says Zaelyra.

"I remember," Rhylor replied. "Keep the tension."

They put it back together. Nym only let him catch his breath after verifying that the ring was still holding.

"Did you follow us?"

"I followed the marks. Not you. The thread of the annex made me believe that a lane was opening up. This one led me to the cistern. He showed the ground. A small turquoise bow was attached to the base of the wall. "Someone wanted her to be found."

"What did you learn from the measurement? Zaelyra asked.

Nym rolled out his sheet. The circles represented air vents; thin arrows indicated the direction of the current. At the place of the tank, three arrows joined while the ducts should have remained separated.

"This connection is not on the plans of my neighborhood."

"It could have been built later."

"Or the plans have been corrected to make it disappear."

Rhylor followed the line without touching the ink. "This duct could feed the inhabited galleries."

"It could also evacuate smoke from a forge. I will only know by measuring the air on the other side."

Nym folded his statement before Zaelyra could copy it. "I can give you the directions, not the names of the families who depend on this catch."

"I didn't ask you."

"Not yet."

He put the paper against his chest. The hidden road may not have been a single road. It was used by people who did not have the same reasons to borrow it. If Zaelyra made her visible in one go, she risked confusing their needs.

Rhylor took out his open circle plate. Nym looked at her without touching.

"This path leads to an old relay? Zaelyra asked.

"At one pass, yes. The relay, I cannot guarantee it. The maps stop before the interesting part."

A flash of light passed in the distance, on the other side of the water. A lantern, then a second. Guards searched the galleries.

Rhylor put the plate back in his pocket. "We have what we need."

"We didn't even understand what we found," says Zaelyra.

"This is just the right time to leave."

They left the boat where it was. Nym erased the turquoise bow from the tip of his boot, but the pale mark remained on the stone.