Garrick Bole had the brass rule in his left hand and the leather finger-cuff on his right forefinger, and he had one hour between the second set and the third, and he meant to spend that hour below the crossing where nobody went. The interval was the only hour in the day when the cathedral was not being held in shape. The six sang without stopping for more than an hour at a time, and between the sets the building settled into something approximate. Ordin Brack put his feet in the cistern water. Nissa Ashkel lay on the loft floor with her arms over her face. Ilde Marrow took the file from her breast pocket and went along her own moustache, one short stroke, two, the way a man checks a blade. Garrick went down. That was the crime, if it could be called a crime. There is no form on which to enter an hour spent below the crossing alone.

The stair to the Wellmouth turns twice, and the water gets louder as you go, because the water is the loudest thing in the cathedral and the cathedral is otherwise the quietest thing anybody has ever built. It smells faintly of a hospital and of eggs. At the foot of the stair the shaft went down into rock, the pool lay in the middle of it, black and warm and perfectly still, and the copper tap stood above the water polished by two centuries of hands.

He had done his station round at the sixth hour. Three bays down the west side of the shaft had bloom at their bases, the soft white spread that means a column is not held, and he had measured them with the rule and chalked a date beside each mark. The third bay had no station number, and that was the thing. Every column on that side carried a number cut into the plinth by the founder’s masons and copied into the ledger ever since. The third bay had a plinth and no number, because at the last walking of the outside count, in the spring, it was a lump of wet white with a shelf on it, and a lump with a shelf is not a column, and so it is not a station, and so it is not a number. Nobody sings at a place with no number. That is not in the book. There is no page for it.

He stood in front of it with the lamp at his knee and did the only kind of thinking he is good at. If a column could be made where there was no page, the four hundred and eleven would become four hundred and twelve and the book would be a lie by one. If it could not, the third bay was a place where the building could be improved for nothing, by anybody, forever, and nobody had tried in four hundred years, because everybody who had stood in that bay was a person with a page. He put his hand flat on the shelf. It was wet and warm, the way the gallery is warm. Then he sang.

He had no intention of singing a new note. He sang the one his stall had been holding since the second hour of the set, the drift note, the one that moves and shapes, and it sat in his throat like a coin in a tooth. He sang it because it was the note he had, and because an hour is a waste if you spend it not singing. He held it eleven minutes. He knows that because the copper tap drips at a rate you can count, and he counted. At the fourth minute the water answered. Not loudly. The pool had a skin on it like the skin on cold tea, and the skin drew in toward the middle and made a ring, and the ring took the note and gave it back a fifth above, which is what the growing gallery does, and which is the reason the choir has not slept properly in a year. At the nine-minute mark the shelf at the base of the third bay came up off the floor.

It did not come up fast. He watched it the way you watch a nail drawn out of a wall. It came in a ring, the way water comes up through a rope, and where it came through the grit it squeaked, because everything on this floor squeaks like snapped sugar and this squeaked too, and he thought that it was going to be a column. At the eleventh minute he stopped, because his throat had gone to sand and the salt was coming up into the roof of his mouth, and he stood with his mouth shut and watched it finish. It came to the height of his knee, the exact width of the plinth above it, which meant the plinth had been a column once, or had been waiting four hundred years for a note to tell it that it was allowed to be one. The crystal was already humming his note, a finger’s width above the pitch he had sung.

He got out his working book and wrote the hour, the bay, the height, and the fact that there had been no one else on the floor. Then he read the line back, and put the book away, and went up. On the stair he stopped, because the water had gone slack, the way a room is slack after a door has been opened and shut in a hurry.

The Ledger Room is eight feet square and deliberately too warm, because a ledger kept in the damp grows a page a season and the book is four hundred and eleven pages and there are no more. One candle, one brass-cornered lectern, one stool nobody but Lida Trask has ever been allowed to sit on. Garrick was not permitted in after the sixth hour. He went in anyway, on the strength of being the clerk, which is the only strength he has ever had, and turned to page eighty-eight. Page eighty-eight is the column at the mouth of the shaft, the nearest entered column to the third bay, its note a low drift note that four singers have carried in a line. Down the outside of every page is a ruled margin where a clerk may record observations about the column that page belongs to.

He wrote the hour and the bay and the height, and that the bloom had set and come up eleven inches and stopped, that it was hard, that it hummed a finger above the pitch, that it was not a column because it had no number, and that there had been no living witness. He signed it, dated it, put the hour down again because he had written it twice, and closed the book, and lay on his bed with salt drying white in the creases of his knuckles.

At the seventh hour the six went up to the stalls. Ordin came out of the cistern with his forearms pale to the elbow and said nothing about the water, which meant the water was wrong. Forty minutes in, the drift note came off its line. A drift note travels along the ruled lines of the columns and the floor, the way water finds a channel, and Garrick’s had been running west all evening. At the twenty-ninth column of the west side it stopped dead, jumped, and picked up again nine inches higher with a click he felt in his back teeth. Nissa Ashkel stopped singing in the middle of a phrase, which she perhaps does twice in a year. The rest of them carried the gap without her the way a line of figures carries a missing one, and she came in on the beat with her jaw shut so hard the muscle jumped.

Afterwards she came down off the loft and stood at the rail and looked at him, the white fringe of her hair stuck to one side of her head with the sweat. “Anything in the ninth rank,” she said. “You stopped.” “I did not stop,” Garrick said. “Something is in the ninth rank.” “You stopped,” she said, “and the leaf is not there. and then there was. and then it was there.” She waited. He understood that she had not answered him at all. Then: “I have been listening to a note for a year that has no column. It is under the floor of the gallery and it is not one of ours. Last night it was yours, and now it is on the other side of something, and the something is not a column.” She said it flatly, without any of it being a complaint, and went up, and slept until the second hour of the morning.

Hesper was reading the cancelled pages at the eleventh hour, because that is her chore, and it is done in the Ledger Room so the damp leaves are not carried about the nave. She read them in order, out loud, standing. “Page one hundred and forty-one, cancelled in the year of the long flood, the gallery stands, it is not entered. Page one hundred and e —” She stopped. “Hesper is on a leaf,” she said. “Hesper has found a leaf.” Between page one hundred and seventy-nine and page one hundred and eighty there was a leaf that had not been there the night before. It was pale and damp and thicker than the others, with a deckled edge you could feel with a thumbnail, and it smelled of the surface, of a wet street a long way up.

The ruling either side of it did not meet. On one side the lines ran to the gutter and stopped. On the other they began again two-tenths of an inch lower, as though the book had been ruled by two people who had never compared notes. “Hesper is turning back. Hesper is turning back and it is not there. Hesper is turning forward and it is there.” Then, because the chore is the chore: “Page one hundred and eighty, cancelled on the reader’s own authority, the gallery stands, it is not entered. Page one hundred and eighty-one —” In the doorway, Garrick Bole had gone the colour of the wall.

They had it out in the Ledger Room with the candle guttering, Lida Trask on the stool, and Garrick standing. Lida Trask was thirty-nine and the book was forty years old in her keeping, and she wore a black ribbon on her left wrist, renewed every twelfth month, for the one column she struck on her own authority in her twentieth year. The two of them understood each other perfectly here, which is that you do the arithmetic anyway. “Page eighty-eight,” she said. “Show me the margin.” He showed her. It was clean. The rule ran down the margin, four parallel lines and the outer edge, and the ink had not struck anywhere on it, and the paper was dry. Garrick Bole did not tidy, and would not have taken it back if he could.

“It is a true line,” he said. “It is in my hand. I wrote it at the second hour. I do not withdraw it and I will not have it said that I did not write it.” “I am not saying you did not write it,” Lida said. “I am saying the page has it. The page has taken it and made a leaf to have somewhere to keep having it, and the book is now four hundred and twelve leaves, and the count on the back page is four hundred and eleven columns. Both numbers are true, and there is no form in this world for a book that is both.”

“The count does not move,” Garrick said. “Per the back page, per the count, the gallery is held to four hundred and eleven and it is held, and the third bay is a pillar eleven inches high that is not a column. I have made the number correct and also made a book with a leaf in it. Which of those two facts am I permitted to keep.” “Both. It is permitted, and it will sit in the middle of the count for the rest of my time, and the cancelling schedule is on the inside cover in my hand, and it has no line for a damp leaf. If the shortfall is not made good by the twelfth month I shall have to write three names on that cover, and I shall have to do it in the same ink.” She turned the leaf over with the corner of a thumb. The back of it was blank, and damp.

Ordin Brack was on the cistern ladder with his back to them and his forearms in the water, and he did not turn round. “Closer,” he said. “The floor carries.” They went closer, which they always did. “The tap is slow,” Garrick said. “Is it.” “The tap was slow at the fifth hour and is not slow now, and I have chalked it down both times, because you cannot argue with a thing you have not marked. The pool is down an inch and a half since yesterday. It came up before I got to it, and it went down on its own between the fourth hour and the fifth.” He wrung the rag out and the pool took it and gave it back. “You can have your book. I have a pool that does what a pool does, and no man has ever told me why.” “Does it sing,” Garrick said. “The thing has not stopped,” Ordin said. “That is the whole of what I have.”

They took it to Ilde Marrow, the only one of the six who could do anything about it, and who had spent two years shortening her own sets in the hope that nobody would count the difference. She ran the file once along her moustache and answered him in the note she had been holding — the sixth, the silence, the one that holds the air out of the other five — so that the reply came up through the floor rather than out of her mouth, and Garrick felt it in his knees. “Then it is a debt,” she said, “and there is a page for a debt, and the page is a leaf, and you have found it in a night. Per the count, that is the fastest work in the history of this book.”

“There is no page for a debt,” Lida said, in her speaking voice, carefully, as a woman reading a figure off a wall. “There is a page for a column. A debt is a column with no page.” “Then what is the leaf.” “A page with nothing on it,” Lida said. “It is damp, and it is not a column, and it is a hundred and seventy-ninth in a hand I did not write, and it will be a hundred and seventy-ninth in the hand of everybody who opens this after me.” And Ilde Marrow, who had been the sixth voice for twenty-two years, dropped to a speaking voice to be kind, and said: “Then give it a line, Garrick. A page with nothing on it is nothing. You are the clerk. You have ruled four hundred and eleven pages and you can rule a line on a damp leaf in a warm room, and you have never once done it for yourself.”

He ruled it at the second hour of the morning with the brass rule laid flat and a pen he had to dip twice, because the leaf drank the first stroke and the second came out grey and thin. One line, down the middle, in the hand of a copying-master, exactly as he had ruled every page in the book. Under the line he wrote: “Third bay, west side of the shaft, no station number. At the interval between the second and third set, being alone on the floor, I sang the drift note and held it eleven minutes. The bloom at the base set and came up to eleven inches and stopped. It is hard and it hums a finger above the pitch. There was no living witness. I enter that I did it, at the second watch, and that it is true, and I am the only person who can say so.”

He dated it and signed it and put the hour down. The ink stayed, which was the whole of the test. He put his thumb on it; the paper was damp and the ink was dry and it did not lift. And when he closed the book, the ruled lines either side no longer failed to meet, because there was a ruled leaf between them with his name on it. A line is a line, and a ruled line is a form, and the fact had a form, and the salt does not lie. It only returns.

“I am the witness to myself,” Garrick said. “Per the law, a note is sung when a living person hears it sung, and I sang it and nobody heard me, so per the law it is a debt. Per the entry, a column is paid for when its note is in this book in ink by hand with a date, and it is, so per the entry it is paid for. Those are two instruments and I played them at once on purpose. I would rather have one line in the book than a fortnight of not sleeping.” “Write the form out again for the record,” Lida said, “and I will countersign it as a witness to the entry, which I am. The law does not ask for two people to have heard a note. It asks for a person to have heard a note and a person to have entered it, and for the first time in four hundred years those two are in the same hour.”

At the seventh hour he took the brass rule and the chalk and did the station round, and the six went up, and the drift note ran west all evening and came off its line nowhere at all. At the third bay he laid the rule flat across the floor and chalked the mark and the date and the arrow, the way the book requires. It was where he had left it the night before. Eleven inches, and no more, and hard, and clear, and humming a finger above the pitch with the green heart in it that all of them had. Behind it, on the plinth above, there had been bloom. There was none now. He measured it out of habit, out of four hundred years of a clerk with a rule in his hand, and found three inches and nothing growing. Then he put the date beside the mark with an arrow, because that is what you do, and stood in the grit waiting. The half-inch a week had stopped. The book had one leaf in it that was not a page, and a debt written down on it in a clerk’s careful hand, and it was that, and not one night of good singing, that had paid for the bay.