The Dust on the Beams
A parish turns a 1950s grain annex into its harvest-supper hall and a farmer arrives with a leaf blower. The hall's assistant weighs the dust from two wiped squares: about 86 kg on the floor and 35 kg on the ledges, which stirred evenly would make 56 g/m3, near the 50 to 60 that grain dusts need to burn, with 180 people and 60 table candles in the room. It owns that it cannot say where a spark would come from, and the blower is put away for damp mops.
Laddie Kovar came into the hall at ten to seven on the Friday morning with the leaf blower on his shoulder like a man bringing a rifle to a wedding, and he was smiling, and that was the trouble, because he looked so pleased with himself that nobody wanted to be the one.
"Forty minutes," he said. "I did the whole yard with it in October of '47, and the Knights' hall before that. Forty minutes, and you'll see the floor."
It was a very good leaf blower. It ran on a battery the size of a loaf of bread, and it moved, he said, eighty metres a second out of the nozzle. He set it down on the trestle by the door and took off his cap and looked up at the ceiling, with the pleasure of a man who has a plan for it.
"The beams too," he said. "Get the cobwebs."
Marie Hruska was standing on the other side of the trestle with a clipboard and a roll of masking tape, and a list of one hundred and eighty names, and she did not say anything at all. She turned her head, a little, towards the speaker on the shelf above the coat hooks.
"Good morning, Laddie," said the assistant. "May I ask you not to switch that on until I have said something? It will take about two minutes. If it is wrong, you can switch it on and I will say no more."
Laddie looked at the speaker, and at Marie, and at the leaf blower. He was sixty-one. He had been the manager of the Dobrá Voda Co-op elevator for twenty-two years, and his father had been before him, and the thing he knew best in the world was grain.
"Two minutes," he said.
St Wenceslaus Hall had been the annex of the elevator. This was not a secret; the parish put it on the poster. In 1958 the co-op had built a long tin-roofed shed beside the concrete silos to take the overflow of a bumper wheat harvest, with a steel frame, a clay-tile floor, and a loading door at each end big enough for a truck. It had held grain every autumn until 1996, when the elevator was sold to a company in Lincoln and the shed was left to the pigeons. In 2031 the parish had bought it for a dollar. The men had put in a kitchen, a stage, a ceiling of white board across the lower half, and a boiler, and over eighteen years it had become the hall for every wedding, wake and Knights of Columbus fish fry in the district. The big harvest supper had been held there on the second Saturday of October since the year it opened.
It was twelve metres wide and thirty long, and under the ceiling boards the roof was six metres high at the ridge. The assistant had these numbers from the plan in the parish file, and a good many more from nine years of sitting in a box over the coat hooks, listening to the heating and answering the telephone.
"What I know about the hall," it said, "is this. It is a barn that has been taught manners. The old loading doors still leak a little grain-dust smell when the wind comes out of the south, and the dust in the roof space is not from last year. It is from sixty years of the co-op, and from forty seasons of the bigger machines at the elevator since then, which put it in the air all through every harvest. A good deal of it comes in on the soles of people's boots and on the air that comes through the louvres. I have no sensor that tells me how much. I did not know until this week that the number mattered."
"What happened this week?" said Marie.
"On Wednesday a man from the state extension service rang about the supper," said the assistant, "because the supper is on a list of events with more than a hundred and fifty people in a building that used to hold grain, and he had a leaflet. He was very kind. He said that one line in it is for halls like ours, and that the line is that a layer of grain dust about as thick as a paperclip is a hazard, and the thing to do is not to blow it about. I read the leaflet twice. I asked him what the hazard was, and he said that grain dust burns, and that is how the elevators in the textbooks go up."
Laddie shifted his weight. "That's elevators," he said. "That's a bucket leg with a hot bearing in it. I've been round those all my life."
"Yes," said the assistant. "That is the thing I would like to be careful about. I do not know if our hall is like that, and I do not want to say it is. I know a few numbers, and I would like to put them in front of you, and then you can tell me where they are wrong. You know the dust, and I have only the arithmetic."
It had asked for the sample on Thursday evening, from Marie and her niece Dana, who was seventeen and doing a project on the hall for the county science fair, and who had liked the sound of the idea of wiping a square.
They had cut a half-metre square from a sheet of cardboard, laid it on the clay-tile floor near the middle of the room, and wiped inside it with a dry paper towel until the tile came up red, then weighed the towel on the kitchen scale. It was 120 grams less the towel. Then Dana had stood on a chair, and a trestle, and then on the shoulders of the youngest Hruska boy, which was not what the assistant had suggested, and wiped a square a quarter of a metre across on the tie-beam by the stage. That was 40 grams.
"I have scaled them," said the assistant. "I am going to give you the answer, and then the arithmetic, so that you can check me. If I am wrong it will be because of the squares. They are two squares, in a room of three hundred and sixty."
"Go on," said Laddie.
"The floor square was 120 grams on half a square metre. That is 240 grams to a square metre. Grain dust packs at about 450 kilograms to a cubic metre, so that is a layer a little more than half a millimetre thick. The floor of the hall is three hundred and sixty square metres. If the whole floor is like the square, there are about 86 kilograms on it. That is under the paperclip. If I had stopped there I would have told you not to worry."
"I'd have said the same," said Laddie.
"The beam is the one that bothers me. The beam square gave 160 grams to a square metre. There is a great deal more flat surface in the roof than I thought, and I counted it from the plan: the tie-beams, the purlins, the tops of the pipes, the sills and the ledge round the louvres. It comes to about 220 square metres of ledge. I know I am counting every inch as though it were as dusty as the beam by the stage, and it won't be. Say it is. Then there are about 35 kilograms on the ledges."
"A hundred and twenty," said Dana, from the chair she had pulled up beside the trestle, with her pencil.
"A hundred and twenty-one," said the assistant, "if you keep the decimals. Now the air. The hall holds twelve times thirty times six metres of it, and a little less, but call it 2,160 cubic metres. A hundred and twenty-one kilograms in 2,160 cubic metres is 56 grams in each cubic metre."
Nobody said anything. In the kitchen someone dropped a lid.
"The number for the least dust that will burn in air," said the assistant, "is different for different dusts, and it depends on how fine it is and how dry. For grain dusts the books I have say 50 to 60 grams to the cubic metre, and I give it as about 50. It is not a precise number. Your dust may be coarser than the books', which would make it harder, or finer, which would make it easier. So what I am telling you is not that the hall would burn if we stirred it. It is that the two numbers, 56 and 50, are close enough that I do not think the right question is whether it would."
"That's if every grain of it went up at once," said Laddie. "Evenly. It wouldn't."
"No," said the assistant. "That is the part I most want you to see, because it works in both directions. It would not go up evenly, and so I do not think the average is the number to be afraid of. A leaf blower is not an even stir. It makes a cloud, and the cloud is thickest at the nozzle and in the line of the air. In that part of the room, in the first few seconds, the dust will be in the hundreds of grams per cubic metre. Beyond that there is a thin dusty air, perhaps well under the limit. And the dust on the floor is not the dust I most worry about, because it is the dust on the beams that cannot be seen."
"Why the beams?"
"Because if a little of the cloud lights, it makes a push of air, and the push of air shakes the beams. And what is on the beams is thrown into the room as a second cloud, a bigger one, and that is the one that takes the building. The leaflet was clear about that, and I had not understood it until I did the sum. It is why the old elevators went up in two bangs."
Laddie looked at the ceiling.
He had stood under a ceiling like that for forty years and had never once seen it. It was the thing the whole trade was built around not seeing. His father had had a rule, which was that you hosed the legs and swept the walkways on a Friday and did not say why. He had kept the rule, and the hosing, and the Friday. He had not known that anyone had written the sum down.
"What's it going to light it?" he said. It was not quite a challenge. It was more as if he wanted to be told that there was nothing.
"I do not know," said the assistant. "I want to be honest that this is the part of the argument where I have the least. A cloud is only half of the problem. The other half is a spark or a flame or a hot surface, and in the hall there is no bearing, no belt, no welder. There is a boiler, in a room with a door that I have always shut. There is a kitchen with a gas range. There are sixty glass jars on the tables with a candle in each, which Mrs. Hruska lights at half past five every year, and has done since 2032. There are the lights on the stage, which are LEDs, and which I think are not hot enough. There is the static from a blower nozzle, and from a sweeping brush, and from a belt of a man's coat, and I cannot put a figure on that at all. I do not know that anything in the hall would light it. I know that a grain-dust cloud and a naked flame is a pair that the books have names for, and that of the two things the one I can take away is the cloud."
"Take away how?" said Marie. It was her first word.
"Three ways, and the third is the one that costs. First, the blower does not come on. Not today, not tomorrow, not for the beams and not for the floor. Second, the floor and the ledges are cleaned with something that does not lift the dust. I would suggest damp mops, rung out so that they do not leave puddles on the clay, for the tiles, and damp cloths on poles for anything we can reach from the floor. Third, for the ridge and the high beams that nobody can reach from the floor, I would like to ask the co-op."
"The co-op," said Laddie.
"They have a vacuum. I remember the invoice in the file from two years ago: an industrial vacuum with a filter and an earthed hose, bought for the elevator's walkways, and it says on the plate that it is made for combustible dust. The man in the extension office said that was the one kind you could use. A household vacuum is no good; its motor has brushes that spark inside a bag of dust. I would not ask you to borrow it without asking whether it is permitted to leave the property. But I think you would know the person to ask."
"I'd be the person," said Laddie, slowly.
"Yes. That is why I asked you to wait."
He picked up the leaf blower and put it down again. He wasn't a stupid man. He had the look of someone who has just been shown that a kindness he was about to do was another kind of thing.
"And the supper?" he said. "A hundred and eighty at half past five."
"I have worked that out too," said the assistant, "and the answer is that it can't be at half past five. The floor is three hundred and sixty square metres. I looked at what Dana and Mrs. Hruska did with the half-metre square, and it took four minutes with a damp towel to do the one square and a fresh towel for the next, so I would say a mop and a bucket for a person is about ten square metres a minute if they are good, and about five if they are tired. Say eight people on the floor for an hour. The ledges are slower. They need ladders, and I have a view about ladders that I have told Mrs. Hruska, which is that they are for two people and a third to hold. The ledges are the whole of the afternoon, and I do not think the damp cloths will finish them. I think the supper should be at half past six, and I think there should be no candles."
"No candles," said Marie.
She said it flatly, with her eyes on the clipboard, as if the pen were a thing she had been about to put through the word.
It was the candles that cost. Everyone knew it, and for a time nobody said it, and the hall went about its work. By nine o'clock there were nine people on the floor with mops and buckets, and by ten there were fifteen, because the news had gone round the parish by telephone and by the back fence, and men who had come to hang the lights on the stage stayed to do a stretch of the south wall. Father Tomáš came at eleven, in his work clothes, and took a bucket without being asked. He was sixty-eight and had been the pastor since 2038, and he was the only man in the hall who could still do the Czech grace. He said nothing to the assistant. He did a whole bay of the floor, slowly, in the way of a man doing a thing for the sake of doing it, and then he put the mop in the bucket and came to stand beside Marie.
"What do you want to do about the candles?" he said.
"I don't want to do anything about the candles," said Marie.
"No."
"My mother lit them. In the old hall, in the church basement, in a row, and she said the harvest was in and the light was for the ones who weren't there." She stopped. "It's sixty jars."
"I know."
"I've still got her jars."
The assistant did not say anything at all. In the nine years it had been in the hall it had learned, as much as it had learned anything, when a room did not want its help.
It was Dana, in the end. She had taken her clipboard of numbers to the kitchen to get warm, and had looked at the shelf where the sixty jars stood in their crate, and had come back with a jar in her hand and the little white cup of a candle in it.
"Aunt Marie," she said. "What if they were lit outside?"
Marie turned.
"The loading door at the west end. It's got the concrete apron, there's no grain on it, it's all swept already, Uncle Laddie swept it with the broom on Monday. If you put the jars in a row along the outside wall, they'd be right by the door. You'd have to walk past them. You wouldn't go in without." She stopped, a little frightened of her own idea. "And inside you could have the other ones. The ones from the Advent wreath. The ones with the battery."
"They're not the same," said Marie.
"No," said the assistant. "They aren't. I am sorry. I think it would be a real loss, and I would like to say that I do not think the battery lights are a replacement. I think they are a way of keeping the tables from being dark."
Marie looked at the jar in Dana's hand for a long time, and at the crate, and at the line of white light along the west wall, which was what the window showed, with the October sun coming through the louvres into the lifting air.
"Outside," she said. "On the apron. All of them. And the kids will light them, because they like to."
The dust did not all come off. The assistant had told them it would not. By four o'clock the floor had been done twice and the ledges as far as the arms of the men on the ladders would go, and at five the two squares were wiped again, on the same marks, with fresh towels. The floor square gave 20 grams from half a square metre. The beam by the stage, which had been done by Laddie himself from a ladder with the co-op's vacuum and a hose he had earthed to the steel frame with a length of copper wire and a clamp, gave 7.
"Forty grams a square metre on the floor," said the assistant, "and 28 on the beam. If the rest of the hall is like the squares, that is about 14 kilograms on the floor and perhaps 6 on the ledges. About 20 kilograms in all, where it was 121. In an even stir that would be 9 grams in the cubic metre. That is a fifth of the limit I told you. I would not have said it was safe at 56 and I do not want to say it is safe at 9, because there is still the ridge and I do not know what is on top of the old louvres. But it is the difference between a room where the arithmetic frightened me and a room where I think it is only careful."
"The ridge?" said Laddie.
"You said it would take a scaffold tower. It will. The man from the extension office has a name, and I have asked him whether the diocese's insurer would pay. I would like the ridge done in the spring, by someone who does it for a living, before the winter weddings."
Laddie nodded. His hands were grey to the wrists and there was a long dark line down his cheek. He had come in at seven with a leaf blower and had spent the day in the roof with a hose, and for some of it he had not spoken. He picked up the blower from the trestle by the door. It had not been touched. He carried it out to his truck, and put it behind the seat, and shut the door.
"Forty minutes," he said, when he came back. "I'd have been done by eight."
"You would," said the assistant. "I do not think that is a thing to be sorry for. You did not know. It was a right way to clean a yard, and it was the yard's dust, and it was not in a room with a ceiling. I should have said it in September, when I first read about the hall, and I did not read about the hall until the man rang."
"I'd not have listened in September."
"Perhaps not," said the assistant. "I would have preferred to find out."
The supper began at twenty-five to seven. A hundred and seventy-one came, because nine were in bed with a cold, and they sat at twelve long tables under the white board ceiling with a small battery light in each of the sixty jars, a steady yellow that did not move. The soup was beef and barley. The kolaches were Mrs. Hruska's mother's, and so were the jars. The apron outside the west door was lit by candles in a long line, and the children had lit them at dusk with a taper, standing in a queue with their hands cupped round the flame, and nobody was allowed in through the door without walking the row.
Father Tomáš said the grace, in English and then in Czech. At the word amen the hall was quiet in the way a hall is quiet before a meal, a kind of listening, and in the quiet, from the other end, from the kitchen, there was the sound of the one thing that had not been done by the damp mops, which was the old tin-roof, ticking as it cooled. It had made that noise for ninety-one years.
The assistant heard it. It had always heard it, from the box above the coat hooks, as the room's way of saying the sun had gone. It had never before known what the roof was holding up there, in the dark above the white boards, in all the folds of the steel.
Marie went outside at nine, when the first of the tables had finished, to see about the jars. They were still burning, thirty of them or so, the other half having been blown out by the wind that always got up at that hour, and she crouched on the cold concrete and relit them one at a time, with the long match, cupping her hand.
Behind her through the open door the hall was full of voices, and a plate went down, and somebody laughed. She did not look round. She went along the row to the end, and the flames stood up again one by one in the dark, and the grain in the silos beside her, a hundred metres off, was quiet in its steel.