When the house was finished it would be the most luxurious home for miles around. The ground floor would be a spacious undercroft, for storage, with a curved vault for a ceiling, so that it would not catch fire. The hall, where people actually lived, would be above, reached by an outside staircase, its height making it hard to attack and easy to defend. Against the hall wall there would be a chimney, to take away the smoke of the fire. This was a radical innovation: Tom had only ever seen one house with a chimney, but it had struck him as such a good idea that he was determined to copy it. At one end of the house, over the hall, there would be a small bedroom, for that was what earls’ daughters demanded nowadays-they were too fine to sleep in the hall with the men and the serving wenches and the hunting dogs. The kitchen would be a separate building, for every kitchen caught fire sooner or later, and there was nothing for it but to build them far away from everything else and put up with lukewarm food.

Tom was making the doorway of the house. The doorposts would be rounded to look like columns-a touch of distinction for the noble newly weds who were to live here. With his eye on the shaped wooden template he was using as a guide, Tom set his iron chisel obliquely against the stone and tapped it gently with the big wooden hammer. A small shower of fragments fell away from the surface, leaving the shape a little rounder. He did it again. Smooth enough for a cathedral.

He had worked on a cathedral once-Exeter. At first he had treated it like any other job. He had been angry and resentful when the master builder had warned him that his work was not quite up to standard: he knew himself to be rather more careful than the average mason. But then he realized that the walls of a cathedral had to be not just good, but perfect. This was because the cathedral was for God, and also because the building was so big that the slightest lean in the walls, the merest variation from the absolutely true and level, could weaken the structure fatally. Tom’s resentment turned to fascination. The combination of a hugely ambitious building with merciless attention to the smallest detail opened Tom’s eyes to the wonder of his craft. He learned from the Exeter master about the importance of proportion, the symbolism of various numbers, and the almost magical formulas for working out the correct width of a wall or the angle of a step in a spiral staircase. Such things captivated him. He was surprised to learn that many masons found them incomprehensible.

After a while Tom had become the master builder’s right-hand man, and that was when he began to see the master’s shortcomings. The man was a great craftsman and an incompetent organizer. He was completely baffled by the problems of obtaining the right quantity of stone to keep pace with the masons, making sure that the blacksmith made enough of the right tools, burning lime and carting sand for the mortar makers, felling trees for the carpenters, and getting enough money from the cathedral chapter to pay for everything.

If Tom had stayed at Exeter until the master builder died, he might have become master himself; but the chapter ran out of money-partly because of the master’s mismanagement-and the craftsmen had to move on, looking for work elsewhere. Tom had been offered the post of builder to the Exeter castellan, repairing and improving the city’s fortifications. It would have been a lifetime job, barring accidents. But Tom had turned it down, for he wanted to build another cathedral.

His wife, Agnes, had never understood that decision. They might have had a good stone house, and servants, and their own stables, and meat on the table every dinnertime; and she had never forgiven Tom for turning down the opportunity. She could not comprehend the irresistible attraction of building a cathedral: the absorbing complexity of organization, the intellectual challenge of the calculations, the sheer size of the walls, and the breathtaking beauty and grandeur of the finished building. Once he had tasted that wine, Tom was never satisfied with anything less.

That had been ten years ago. Since then they had never stayed anywhere for very long. He would design a new chapter house for a monastery, work for a year or two on a castle, or build a town house for a rich merchant; but as soon as he had some money saved he would leave, with his wife and children, and take to the road, looking for another cathedral.

He glanced up from his bench and saw Agnes standing at the edge of the building site, holding a basket of food in one hand and resting a big jug of beer on the opposite hip. It was midday. He looked at her fondly. No one would ever call her pretty, but her face was full of strength: a broad forehead, large brown eyes, a straight nose, a strong jaw. Her dark, wiry hair was parted in the middle and tied behind. She was Tom’s soul mate.

She poured beer for Tom and Alfred. They stood there for a moment, the two big men and the strong woman, drinking beer from wooden cups; and then the fourth member of the family came skipping out of the wheat field: Martha, seven years old and as pretty as a daffodil, but a daffodil with a petal missing, for she had a gap where two milk teeth had fallen out and the new ones had not yet grown. She ran to Tom, kissed his dusty beard, and begged a sip of his beer. He hugged her bony body. “Don’t drink too much, or you’ll fall into a ditch,” he said. She staggered around in a circle, pretending to be drunk.

They all sat down on the woodpile. Agnes handed Tom a hunk of wheat bread, a thick slice of boiled bacon and a small onion. He took a bite of the meat and started to peel the onion. Agnes gave the children food and began to eat her own. Perhaps it was irresponsible, Tom thought, to turn down that dull job in Exeter and go looking for a cathedral to build; but I’ve always been able to feed them all, despite my recklessness.

He took his eating knife from the front pocket of his leather apron, cut a slice off the onion, and ate it with a bite of bread. The onion was sweet and stinging in his mouth. Agnes said: “I’m with child again.”

Tom stopped chewing and stared at her. A thrill of delight took hold of him. Not knowing what to say, he just smiled foolishly at her. After a few moments she blushed, and said: “It isn’t that surprising.”

Tom hugged her. “Well, well,” he said, still grinning with pleasure. “A babe to pull my beard. And I thought the next would be Alfred’s.”

“Don’t get too happy yet,” Agnes cautioned. “It’s bad luck to name the child before it’s born.”

Tom nodded assent. Agnes had had several miscarriages and one stillborn baby, and there had been another little girl, Matilda, who had lived only two years. “I’d like a boy, though,” he said. “Now that Alfred’s so big. When is it due?”

“After Christmas.”

Tom began to calculate. The shell of the house would be finished by first frost, then the stonework would have to be covered with straw to protect it through the winter. The masons would spend the cold months cutting stones for windows, vaults, doorcases and the fireplace, while the carpenter made floorboards and doors and shutters and Tom built the scaffolding for the upstairs work. Then in spring they would vault the undercroft, floor the hall above it, and put on the roof. The job would feed the family until Whitsun, by which time the baby would be half a year old. Then they would move on. “Good,” he said contentedly. “This is good.” He ate another slice of onion.

“I’m too old to bear children,” Agnes said. “This must be my last.”

Tom thought about that. He was not sure how old she was, in numbers, but plenty of women bore children at her time of life. However, it was true they suffered more as they grew older, and the babies were not so strong. No doubt she was right. But how would she make certain that she would not conceive again? he wondered. Then he realized how, and a cloud shadowed his sunny mood.