The knocks did not stop when Cael moved. They only slowed, the way a heartbeat slows when it has decided the danger is patient and can be met later. Mara stood with the count spoiled in her mouth. Five, and then the wet sound of his boots, and then nothing she could trust to be five.
"I need to see the first one," she said.
Nessa turned from the wall. "Sile took the door. You watched her take it."
"I watched her go in. The Ledger records that the unnamed can hold the door. It does not say the holding is finished by going in." Mara heard her own voice climbing the numbered stair it climbed when she was frightened. "There are three points I have not verified. One, that the door is held. Two, that holding it costs nothing I failed to read. Three, whether the count I lost is the count that binds."
"You lost it because he moved," Nessa said, not unkindly, and looked at Cael as though he were a draught under a door.
Cael had already crouched by the open panel. He was fitting the board back into its frame, working the warped edge against the swollen wood with the flat of his thumb, testing where it caught. He did it the way other men breathe. Mara watched his hands find the bind in the grain and ease it, and she thought, with the small treachery of a mind that would not stay on task, that she had never once seen him leave a thing hanging crooked while people talked over it. It was the only steadiness in the room. She resented needing it.
"Drain course runs behind the archive stair," he said, not looking up. "Sile's door lets onto it. If you want to see her, we go now, before the tide turns the water back into the low tunnel." He set the board and stood. "I'll take the child."
"Elian stays with me," Nessa said.
"Elian stays with the man who presented him," Mara said. "The Ledger bound them. If Cael goes into the drain, Elian goes into the drain." She did not enjoy saying it. She said it precisely, which was the same to her as saying it kindly.
They went single file, Cael first with the lantern and the boy against his shoulder, Mara behind, Nessa last with her undertaker's bag knocking her hip. The drain course was a stone throat that sweated. Old iron rungs, salt-eaten to lace, marked where inspectors had once descended in a time when the town still inspected things it did not want to see. The knocking followed them along the wall at their left, keeping pace, spaced and unhurried.
Mara counted the sealed alcoves as they passed. She could not help it. Second door. Third. Each was a bricked arch with a sill worn smooth, thresholds that had once been the backs of houses before the streets were raised and the lower town buried itself against the winters. Six of them stripped of the Watch's protection when Tovan took the station duty. She had ruled that the unnamed could hold them. She had thought the word for that ruling was mercy.
Sile's door was the first alcove past the archive stair.
The woman sat inside it, on the sill, with her back to the bricked arch as though the bricks were a chair she had always owned. That much was as Mara remembered. But the lantern found her wrong. Her hair was wet. Not damp from the tunnel's sweat, but wet through, hanging in ropes, water beading at the ends and dropping and beading again, and it did not dry in the hour they stood there, and it would not, Mara understood, dry at all. Salt had dried white at the corners of Sile's mouth. When she smiled — she did smile, at Elian — her lips cracked and did not bleed.
"Low tide came," Sile said. Her voice had gone quiet at the edges, the way a voice does over water. "It came to the door. It wanted in. I held the sill." She turned her hands over. The palms were pruned, white and ridged, the hands of someone drawn out of the harbor after too long. "It's colder in me now. That's the price of it. A little colder each low water. I don't mind yet."
"Yet," Mara repeated.
Nessa was already down beside her, thumb under the woman's jaw, tilting her face to the light, reading her the way she read the newly born and the newly dead. "Her lips. Her nail beds." She spoke to Mara over her shoulder without softening it. "You didn't seat a guard here. You seated a shore. The sea can't cross the sill, so it drinks the one who holds it. Slow. One tide at a time. It'll take her the way the water takes anyone. It's only being polite about the speed."
Mara stood very still. The count in her head reordered itself against her will. Six doors. Six low tides a fortnight. She did the arithmetic she did not want and arrived where she knew she would arrive.
"That is not what the clause said," she said.
"The clause said the erased can hold the door without surrendering a roof." Cael had set Elian down on a dry ledge and was crouched at Sile's sill, running his fingers along the mortar where the water had reached. He found the high mark, a dark line, and pressed it, and it gave under his thumb, soft as bread. "It didn't say without surrendering anything. You read it for the roof because the roof was what you were afraid of." He said it flatly, no accusation shaped in it, which was worse than accusation. He took a folding knife from his coat and began scraping the ruined mortar back to sound stone, so the next tide would meet a clean edge instead of a rotten one. Buying Sile an hour, maybe. A tide. Something.
Mara watched him do it. He would not save anyone with a knife and a bad joint of mortar, and he knew it, and he was doing it anyway, carefully, because the alternative was standing in the dark being useless while a woman went cold. That was the thing she could not put down. He had every reason to let this town drown and instead he was mending its buried thresholds one scrape at a time, and he had not once looked at her for permission or for thanks.
"Then I have condemned her," Mara said.
"You've delayed her," Nessa said. "There's a difference to the one waiting. Don't take it from her by naming it a death before it is one."
The knocking, which had gone quiet at Sile's door, began again further along. The second alcove. Patient. Then the third answered it, and the fourth, spaced out down the drain like watchmen calling the hour.
"They know," Sile said. She did not sound afraid. She sounded like someone recognizing neighbors. "They've been in the walls a long time, the ones the town forgot on purpose and the ones it forgot by accident. They heard the wall change. They know there's work now that only we can do." Water dropped from her hair to the sill and ran toward the low tunnel. "There's more of us than you have doors, Examiner. You could seat one at every sill and still not empty the walls."
"Five doors remain," Mara said. "I counted five knocks."
"You counted five before he moved," Nessa said quietly. "You said so yourself."
And there it was. Mara felt the floor of the thing open under her. As Examiner she had counted, and counting was ruling; the number she reached was the number the Ledger would hold true. She had reached five and lost it. If the walls held six who would answer, or seven, and she had declared five with her own frightened arithmetic, then a door stood unaccounted, and an unaccounted door was an open one, and an open one received the sea.
She turned to Cael. He had stopped scraping. He was watching her the way he watched a strap before it failed, looking for the place it would tear.
"I have to count them again," she said. "All of them. Every knock in the wall, exactly, before the tide turns, or my mistake becomes the town's."
"You can't count what won't come out," he said. "They knock. They don't line up to be tallied."
"Then I go door to door and I open each one until I have the true number." She heard herself and could not stop. "One. I open the second alcove. Two. I record who answers. Three—"
"Three," Nessa cut in, hard, "every one you open and speak to, you seat. That's the shape of it. You saw Sile. You open a door to count it and someone's on the other side and the sea's coming and you'll seat them because you can't leave the door bare. You won't be counting, girl. You'll be spending people to fix a number."
Mara stopped on three. The tunnel dripped. Down its length the knocking went on, and she understood that she could not tell any longer whether it was four separate hands or one hand at four distances, and that the not-knowing was itself the trap, because to resolve it she would have to open, and to open was to bind.
Sile shifted on her wet sill. "I'll count for you," she offered. "I can hear them from in here. I'm one of them now." She tilted her dripping head against the brick and closed her eyes, and her lips moved, and Mara realized the woman was already saying numbers, softly, the way Mara herself did, the way the cold does when it comes up through the feet — and could not tell, in the lantern light, whether Sile had reached the true count, or whether she had simply learned, in one low tide, to count the way the sea counts, which is to say without ever arriving at the last.