Spring reached the quarry before it reached the valley. The trucks ran from six. The weighbridge kept its own weather: dust, diesel, and small brass numbers sliding under glass. We had work again. Work is its own weather.
The trouble came by cart, in four wooden boxes, from the river station: four hundred letters, every one of them labelled. The river station had done its own labelling, as the district required, and it had done it from a street book. The street book was two years old. In the winter the district had added two numbers to the end of every door, and nobody had told the book.
So the labels were wrong. Not scattered wrong. Wrong in one direction, all of them, the way a clock is wrong when it is an hour behind. Every label pointed at the house next to the right one.
We taught the line on that batch for six days. It learned fast, the way it always did, and then it stopped. Thirty-one letters in a hundred wrong, and the same thirty-one on Tuesday and on Wednesday. The child had a column for that now, ever since the slope. She counted how long a number takes to stop moving. It had never stopped so quickly.
Fast is good, the grey technician said. Fast is cheap. The child looked at the wall. Fast is early, she said. It stopped in the wrong place.
She took the batch apart on the weigh office floor, under the brass numbers, and asked a question none of us had asked it. Not what the line had learned. What it had learned from.
The answer was plain once she said it. Every letter whose door number ended one lower had been read as though it ended correctly, not always, but so often that the line had made a habit of it. The line had not learned the letters. It had learned the mistake, learned it perfectly, and been rewarded for it exactly as if it had been right.
A wrong label is not noise, she said. It is a lesson you did not choose.
Our quarry cousin stood at the door with a weigh ticket in each hand. DESCENT does not argue much; he carries. A slope does not know why a load is heavy, he said. It only knows it must move. If the ticket says four tonnes and the truck is empty, the slope will still learn four tonnes. He said it without blame. He had said the same thing about himself.
The eldest had spent a lifetime asking for the rule that would have prevented this. That night he asked a smaller question, and wrote it at the top of a clean page: WHO WROTE THIS LABEL, AND WHAT WERE THEY LOOKING AT. Under it, one line. River station. Street book. Winter. Not told.
The method came from the child, and it cost us tags. Labels are the one thing the district rations; we had a hundred a month. She took fifty letters and had two readers read them separately, without speaking, without seeing each other marks. Where they agreed, the label stood. Where they disagreed, a third reader opened the letter, and only those were labelled again. Fifty letters cost us forty tags, half a day, and one argument about whether the second reader was worth the wage.
At nine that night Merta came up from the printing office with a district form and a pencil behind her ear. The form had one line for a signature and a sentence above it: THE BATCH WAS CORRECTLY LABELLED. She put it on the counter and pushed it across. Sign it and I can go home, she said.
No, said the eldest. Then sign that you were told, she said, and it was not a kindness and not a threat; it was the way she had learned to work with us. He wrote in the margin, small: labelled by: unknown. The child wrote under it: read by two, then a third. Where they disagreed, we opened the letter.
Merta read it twice. Then she signed her own name under our line, the first time we had seen her name on anything that was not a postal form, and carried the form away into the dark.
The line, retaught on the fifty letters we had relabelled, came down to twelve wrong. Then it stopped again, and the child wrote down where, and how long it had taken to get there. Eleven days. She put the two numbers side by side on the wall: thirty-one in six days, twelve in eleven. A wrong label does not slow the line, she said. It satisfies it.
That night she hung one of the new cards on the shelf where the key lay, beside the closed promise ledger. On the card, in her small hand: OPEN IT WHEN YOU CAN SAY WHAT IT WILL TELL YOU. To lift the key now, a person had to take the card first. The eldest came in late, dusty to the elbows, took the card down, read it by the lamp, and put the key back on the shelf with the card behind it, so that next time it would be in his hand before the key was.
The district put up its fourth table that spring, and none of us could say what the river station would print on it. But we knew something we had not known in the winter: a number can be right about the world and wrong about the letter, and the difference is written by somebody hand, on a day, from something they were looking at.
House of Sparks is a work of fiction. The family, the valley, the stations and the tables are invented. The milestones are not.