At the yard she went straight to the back wall.
It was midday. The hands were at the bins, Tavin was at the melt pit, and two carters from the dock guild were waiting by the gate with an empty wagon for a load of sorted conduit, smoking and stamping their feet in the cold. Nobody paid attention to her. She took the chalk from her apron and stood in front of the brick beside the debt column, in the clean space where nothing had been written, and began.
First the dots.
Nine of them. She drew them as Halvek had named them, as the primer had always named them: nine lamp systems on the Compact’s list. She had no idea where they really were in the sky. Nobody in the Low Brace knew that; the Compact’s chart had shown them as gold circles arranged in a rough spiral, the oldest at the center and the others winding outward, and she drew them that way now, from memory, a spiral of nine dots on the brick. She labeled the ones she knew. Hearth near the outer edge. Lorn, further out still. Meridian at the center.
Then she opened the notebook to the column she had copied and began placing dates.
Sorrel and Whitlow had their hollow rings on the chart, and she put them where the chart had put them. Sable was harder. But the register’s margins had given her something: beside Sable’s collapse, the clerk in his tight small hand had written the system that took in its refugees, Sable, refugees to Lorn and Tal, and the chart’s open paper on the outer turn, where a ninth circle ought to be, sat between those two. She drew Sable there. Then she put a small chalk cross on each of the three dead dots, with its year and month, and a smaller ring beside Lorn for its rise.
When the last one was on the wall she stepped back to look.
The crosses moved inward.
She had half expected it, from the arithmetic in the records hall, but seeing it on the wall was different. The earliest failure sat beside the outermost dot, far out on the spiral’s last turn. The next sat a little further in. The next further still. Each later date lay closer to the center than the one before, and the line they made ran straight. It never jumped about the way failures from age would jump, one here, one there, wherever metal happened to be tired. It leaned. It ran in a long steady curve, inward, along the spiral, toward a single point near the middle.
And the gap she had found in the register, the missing two years, fell exactly where the curve passed between Sorrel and Whitlow.
She stood with the chalk in her hand. Behind her the carters were laughing at something. The melt pit hissed as Tavin raked it.
She checked each cross against the notebook before she let herself believe the line. Dates first. Positions second. Then the line. That was the order Tavin would want, and she wanted it too.
Tavin came out of the pit shed a few minutes later with a water cask on his shoulder, heading for the trough. He saw the wall. He stopped.
He set the cask down on the cobbles and came closer and stood beside her, looking at the dots and the crosses and the dates. He said nothing for a while. She watched his eyes follow the line from the outermost cross inward, slowly, cross by cross.
“Who told you the lamps keep dates?” he said at last.
“The register did. The tithe register. In the margins.”
“The register doesn’t know the lamps.” His voice gave nothing away. “The register knows households. Some clerk with nothing to do writes rumors in a margin, and you chalk them on my wall.”
“They’re not rumors. They’re dated. Every one of them.” She pointed at the outermost cross. “That one failed ten years ago. That one six. That one a little over three. They’re getting closer together. And they move. They move in a line.”
“Lamps fail from age,” Tavin said. “The Compact says it. The Compact’s engineers say it. Old metal, old hearts. That’s what the record says.”
“Age doesn’t walk in a line.”
He was quiet.
“If they were failing from age,” Mara said, “they’d fail all over. Wherever the metal was oldest. Wherever the heart was worst. It’d be random, or it’d follow how old they are. These don’t. They go inward. One after another, along the spiral. As if somebody were walking down a list.”
“The Compact blames age,” Tavin said. “And the Compact has the seals. The Compact holds every maintenance seal on every lamp in the nine systems. So the Compact has the last word on what killed a lamp.” He looked at her. “That’s how it works.”
“The wall has more words than the Compact,” Mara said.
He did not answer that. He rubbed a thumb along the edge of the bench where the varnish had worn through, back and forth, as if testing it for a burr.
One of the carters had drifted over from the gate, curious, his pipe in his teeth. He was a big red-faced man with a guild badge on his cap. He stood behind them and looked at the wall for a while, reading the dates, puzzling over the dots.
“That’s the lamps, is it?” he said.
“Yes.”
He squinted. “So which one’s next?”
Mara looked at the wall. She looked at the curve of crosses, at the place where it was heading, and followed it with her eyes the way she would follow a stress line down a landing leg, to the next weakest seam. The curve came in along the spiral’s outer turns, past Lorn, and it was bending toward a dot she had drawn near the outer edge but not at it, a little inside the path the failures had made.
She found it. She did not need to look for the label. She had written it herself.
Hearth.
It sat squarely on the line. The next turn of the curve, if it held its lean, would pass straight through Hearth’s dot on its way inward.
Below the dot, in smaller letters, she had written Cinder, and below that, smaller still, because she had been drawing from habit, the way she would label a map of the district for a delivery: Low Brace.
The carter followed her eyes to the dot and read the label. He laughed, a short loud laugh, as if she had told a joke.
Then he saw the chalk. He saw the crosses and the dates and the curve, and Mara’s finger resting just beside the dot with Low Brace written under it, and the laugh went out of him all at once, like air out of a punctured bladder. He took the pipe out of his mouth.
“That’s not funny,” he said.
“No,” Mara said.
He stood there a moment longer. Then he put the pipe back in his mouth and went back to the wagon and said something low to the other carter, and they both looked at the wall from across the yard and then away.
Tavin had not moved.
Mara stepped up to the wall again. At the center of the spiral, the point where the curve was gathering, the place every cross was leaning toward, there was the dot she had labeled Meridian, the oldest lamp, the Compact’s seat. But the curve aimed a little to one side of Meridian itself. It aimed at a point just beside it, a little below, where she had drawn nothing at all, because the chart had shown nothing there.
She took the chalk and drew a small mark at that point. A question mark. She wrote nothing beside it. She could not think what to write. A well, perhaps, or a hole, or a place where a list began. She left the question mark alone on the brick.
Tavin picked up the water cask and set it on his shoulder again.
“Clear the wall before the shift,” he said. “Before the hands come back from their meal.”
“Why?”
“Because the hands can read,” he said, “and the carters talk, and by nightfall half the Low Brace will be standing in front of my yard asking if Hearth is next. And you can’t tell them.” He looked at the question mark. “You can’t tell them anything. You don’t know.”
He walked off toward the trough.
She stood in front of the wall with the chalk in her hand and the rag in her apron pocket. She could rub it all out in half a minute. She looked at the curve, the crosses, the Hearth dot with Low Brace written under it in her own careless hand.
She did not take out the rag. She looked at the question mark in the middle, the only thing on the wall she had not got from someone else’s record, and left it there, unlabeled, for somebody besides herself to look at and check.