The morning of Sirocco was a jar, and on the morning it went missing, Ivo Tarrow counted it out on a cold platform at Emberwhistle Halt and found it in the wrong crate. The bells went at four. Eleven jars stood on the planks in front of the booth, brass and sand-crusted, each with a blue loop on the handle. Ivo counted them twice. “Eleven,” he said. “There should be twelve.” The twelfth slot was empty, and beside it the chalk said NINETY-ONE, in his own shaky hand from winter.

Nim Ferrous was waiting for the Long Noon with her bag. She had a single copper braid down one side of her head, tied off with blue twine. “Jar ninety-one is in crate four,” said Ivo. “Take it out and put it on this plank.” It was a night jar. You could tell by the brass collar, which was cut with a notch. Morning jars have a flat collar, and it is the only way anybody can tell them apart in the dark. “Ninety-one is a night jar.” “Then the morning is somewhere else.”

“The morning is a hundred and ten minutes away, sitting in a crate at Kellvetch, or the morning is gone.” He wrote on the board. NINETY-ONE. NIGHT. NOT MORNING. Then he looked up. “I am sending this east on the wire. Then I am going back inside, because a man who has counted a thing wrong does not stand out in the cold being looked at.”

The Long Noon went east under six great canvas gasbags, rising as it spent its stored hours. Behind the coal door was the Ledger Room, narrow, lined with steel, and always warmer than outside. Sol Brannen sat there in white gloves with a green glass lamp over the desk, the right thumb of his glove stained green into the weave, and the engine’s heartbeat coming up through the floor a half beat behind his writing. He read the wire out loud. “Emberwhistle to the Long Noon. Jar ninety-one is a night jar. Crate four. I. Tarrow.”

Nim was sent to fetch the crate, and she came back with the seal broken in a hurry. The noon market at Sirocco was the biggest day of the month, and the day had no morning to start it. Sol put two fingers on the Ledger and read out the line his own hand had written four days before. “Jar ninety-one. Morning. Sealed at Kellvetch. Confirm you heard that correctly.” “Yes, sir.”

“Ledgers cannot be un-written,” he said. “They can only be carried forward. So this line is true, and something after it is false, and the something is either a hand that picked up the wrong jar, or a hand that wrote the wrong word. A machine cannot lie. A man can, with a perfectly good pen.”

Sirocco at nine in the morning was cold, and dark, and wrong. The town was built in the lee of a three-hundred-foot dune, and the Underdune Bazaar was roofed with stretched canvas, and every stall lit its own lamp with bottled sunrise, so the market ran in low amber light from before dawn until noon. It was the reason people came. It was amber light in a country that had white light and then nothing. Now the canvas was grey, and the stalls stood in rows with their lamps burning thin and low, and nobody was under them.

“Nobody is at the stalls,” said Nim. “Nobody is awake,” said Marmalade. Marmalade was nine, and she lived under the brake van, and one of her boots was a full size too small with its cuff patched in cut tin. She stood in the dark street with her face tipped back at the sky. “They are asleep,” she said. “It is nine, and the baby on number six was crying at seven, and now the baby is quiet, and that is worse.”

“The loud man was here,” she said a minute later. “He came through the bazaar yesterday with two porters and a crate, and he did not go to a stall. He went to the back, where the curtains are.”

Behind the third curtain sat Septimus Vail, in a white panama hat, with sunglasses cut from smoked window glass, and a lantern turned down low on the table. “Seventy minutes,” he said, before anybody had spoken. “My price to open this booth. Seventy minutes each, cut from your own lives, and I take coin as well, because coin is what people have. Same again?” “We are not here to buy,” said Nim.

“You have wasted seventy minutes, and I am sorry, and it is still seventy minutes.” He did not get up to shut the booth. “Nobody ever comes here to look at the weather. What do you want?” “We want to know where your morning went,” said Marmalade.

“I have a morning,” he said. “Jar three hundred and six, bottled at Kellvetch in the last vats, warm as bread. It came down on the noon cart on Tuesday and it has been sitting behind this curtain since Tuesday, and I cannot sell it, because nobody in Sirocco wants a morning they already have.” Nim felt the cold come up through the soles of her boots.

“The crate he put in the market was the wrong one,” Marmalade said, in a confidential whisper. “I heard the man with the porters say crate four was for the town, and the man in the hat said the town would not notice till the lamps went.”

Sol Brannen came up to the booth with the Ledger under his arm and put it on the table with a thump. “Jar ninety-one,” he said. “Morning, per the manifest. It arrived in Sirocco as a night jar, and my clerk at Kellvetch signed the crates, and his name is on the sheet, and I will not be the man who says the word was wrong without a figure first.” Vail took his sunglasses off. His eyes were red at the rims.

“Ninety-one is not the number on this jar,” he said. “Three hundred and six is on this jar, and three hundred and six is a morning, and I have not had a hand on ninety-one since Tuesday when it went out on the noon cart.” “Then somebody in your trade is holding Sirocco’s morning,” said Sol. Vail put the sunglasses back on.

“The morning goes back to the town tonight, on the four o’clock, free, because I would rather be the fool who gave it away than the thief who kept it. And in exchange the Underdune Bazaar gives me its light for a year. Every stall, every lamp, every jar of bottled sunrise the bazaar owns, counted onto my cart before the four o’clock. Three thousand six hundred of them, or thereabouts. That is my price, it is the Yards’ price, and I have never shaved a figure off a jar in my life.”

“Three thousand six hundred,” said Nim. “Or thereabouts,” said Vail. “That is a year of light for one morning.” “That is what a morning is worth. Ask the Yards.” He spread his hands. “I am not the fat cat. I am the man with the only jar in the basin that opens onto a sunrise. Walk out into the dark if you like, and have no morning at all.” Nobody walked out. Marmalade counted the stalls out loud on her fingers, and by noon the bazaar was a counting floor.

There were sixty-one stalls. They counted them twice, and it was sixty-one both times. “Six stalls have eight lamps each,” said Nim. “That is forty-eight. Fifty-five stalls have one each. That is fifty-five. That is one hundred and three stalls, and three thousand and ninety bottles, and we have not done the cook-stoves or the children’s lanterns yet.” By dusk they had done the cook-stoves, the bell-ringers’ lanterns, and the fourteen loose bottles under the children’s stall, which Nold Quill counted personally, twice, and would not let anybody else touch. “Three thousand five hundred and forty-one,” said Nim.

“Three thousand six hundred,” said Vail. “There is your arithmetic,” said Ferrite, from the end of the row, “with your own figures on it.” “There is the night jar,” said Marmalade. “Ninety-one is a night jar. It is in a crate in the rail-shed behind the bacon stall, because I saw it when the porters put it down, and the porter said a night is worth a hundred of a morning.” Vail took his sunglasses off again. “Ninety-one is in the rail-shed. In my shed, under my lock.” “Then we have three thousand six hundred and forty-one,” said Nim.

Vail was quiet. Then he wrote a figure on the back of a bill and turned it round so that everybody could see it. Three thousand six hundred and forty-one, he wrote. Paid. Witnessed by S. Brannen, who read the number out loud and asked whether she had heard it correctly, and then asked Marmalade, and then, after a while, asked her again.

They did not open jar three hundred and six in the bazaar. Sol said the ground under a jar opened out of its season is sterile for a year, and a year of sterile ground in a market is a year nobody eats. So they carried it up to Balloonmast Ridge, where six mooring masts stand eighty feet tall, on bare red stone that nothing has ever grown on, and there is nothing to sterilise. The four o’clock was late, because the Long Noon had to burn hours to get up the ridge, and Captain Ferrite gave the order himself.

“Right. Listen. Ballast light, two hours, and I will answer for every minute of it in the book. Nobody touches the jar until the light is right. Children, stand behind the mast feet.” Marmalade stood behind a mast foot. Nim stood beside her. Sol had the Ledger open on a crate, reading the time out loud as the light came over the ridge, at half past four in the afternoon, which was not a thing the sun did there. The glass of the jar went from grey to gold to the colour of the inside of a loaf.

And the light came over the ridge and down onto the sand and across the whole of Sirocco at once, warm and low and slanted, the way a morning is supposed to be. Every dog in the town started barking at the same time. “It is a sunrise,” said Marmalade. “It is a whole sunrise and it is half past four in the afternoon.”

The children of Sirocco came out into the street. There were a great many of them, and they stood in the amber light with their faces turned up, and nobody moved a lamp, because there was nothing left to move one with.

The bazaar was dark inside for a year after that. That was the price, and the town had counted it themselves, stall by stall, and nobody could say they had not known. Nold Quill swept out her front on the first morning without lamps, and stood in the doorway with the broom in her hands. “A year,” she said. “Well. It is a market. It will wait.”

Vail came and went that year, and did very well selling noon light to the places that had it, and said “same again?” to everybody. And Marmalade told everybody, in a whisper, before they had agreed to anything, that the man in the white hat gave the morning back for nothing and was frightened of his own arithmetic. Both of those things turned out to be true.

The Long Noon stood at Sirocco one more night, and in the morning Ferrite burned the hours to get to the west end. Sol Brannen carried forward the line about jar ninety-one, because a Ledger cannot be un-written, and wrote a second line under it in green ink, in the same hand: WRONG WORD. FIND IT. “Seventy minutes,” said Vail, when they came for the twenty minutes they still owed him. “Same again?” “No,” said Nim. “We counted.”

And Ivo Tarrow, at the far end of the Line, kept the chalk on his board, and every morning for the rest of that year he wrote NINETY-ONE, NIGHT, NOT MORNING for the next man, until the words wore down to a ghost of themselves. That is the arithmetic of it.