“Good.”

Jack smiled. “When I left Kingsbridge, riding my mother’s horse, with my stepfather’s tools in a satchel slung across my shoulder, I thought there was only one way to build a church: thick walls with round arches and small windows topped by a wooden ceiling or a barrel-shaped stone vault. The cathedrals I saw on my way from Kingsbridge to Southampton taught me no different. But Normandy changed my life.”

“I can imagine,” Raschid said sleepily. He was not very interested, so Jack recalled those days in silence. Within hours of landing at Honfleur he was looking at the abbey church of Jumièges. It was the highest church he had ever seen, but otherwise it had the usual round arches and wooden ceiling-except in the chapter house, where Abbot Urso had built a revolutionary stone ceiling. Instead of a smooth, continuous barrel, or a creased groin vault, this ceiling had ribs which sprang up from the tops of the columns and met at the apex of the roof. The ribs were thick and strong, and the triangular sections of ceiling between the ribs were thin and light. The monk who was keeper of the fabric explained to Jack that it was easier to build that way: the ribs were put up first, and the sections between were then simpler to make. This type of vault was also lighter. The monk was hoping to hear news from Jack of technical innovations in England, and Jack had to disappoint him. However, Jack’s evident appreciation of rib-vaulting pleased the monk, and he told Jack that there was a church at Lessay, not far away, that had rib-vaulting throughout.

Jack went to Lessay the next day, and spent all afternoon in the church, staring in wonder at the vault. What was so striking about it, he finally decided, was the way the ribs, coming down from the apex of the vault to the capitals on top of the columns, seemed to dramatize the way the weight of the roof was being carried by the strongest members. The ribs made the logic of the building visible.

Jack traveled south, to the county of Anjou, and got a job doing repair work at the abbey church in Tours. He had no trouble persuading the master builder to give him a trial. The tools he had in his possession showed that he was a mason, and after a day at work the master knew he was a good one. His boast to Aliena, that he could get work anywhere in the world, was not entirely vain.

Among the tools he had inherited was Tom’s foot rule. Only master builders owned these, and when the others discovered Jack had one, they asked him how he had become a master at such a young age. His first inclination was to explain that he was not really a master builder; but then he decided to say he was. After all, he had effectively run the Kingsbridge site while he was a monk, and he could draw plans just as well as Tom. But the master he was working for was annoyed to discover that he had hired a possible rival. One day Jack suggested a modification to the monk in charge of the building, and drew what he meant on the tracing floor. That was the beginning of his troubles. The master builder became convinced that Jack was after his job. He began to find fault with Jack’s work, and put him on the monotonous task of cutting plain blocks.

Soon Jack set off again. He went to the abbey of Cluny, the headquarters of a monastic empire that spread all across Christendom. It was the Cluniac order that had initiated and fostered the now-famous pilgrimage to the tomb of Saint James at Compostela. All along the Compostela road there were churches dedicated to Saint James and Cluniac monasteries to take care of pilgrims. As Jack’s father had been a jongleur on the pilgrim road, it seemed likely he had visited Cluny.

However, he had not. There were no jongleurs at Cluny. Jack learned nothing about his father there.

Nevertheless, the journey was by no means wasted. Every arch Jack had ever seen, until the moment he entered the abbey church of Cluny, had been semicircular; and every vault had been either tunnel-shaped, like a long line of round arches all stuck together, or groined, like the crossing where two tunnels met. The arches at Cluny were not semicircular.

They rose to a point.

There were pointed arches in the main arcades; the groined vaults of the side aisles had pointed arches; and-most startling of all-above the nave there was a stone ceiling that could only be described as a pointed barrel vault. Jack had always been taught that a circle was strong because it was perfect, and a round arch was strong because it was part of a circle. He would have thought that pointed arches were weak. In fact, the monks told him, the pointed arches were considerably stronger than the old round ones. The church at Cluny seemed to prove it, for despite the great weight of stonework in its peaked vault, it was very high.

Jack did not stay long at Cluny. He continued south, following the pilgrim road, diverging whenever the whim took him. In the early summer there were jongleurs all along the route, in the larger towns or near the Cluniac monasteries. They recited their verse narratives to crowds of pilgrims in front of churches and shrines, sometimes accompanying themselves on the viol, just the way Aliena had told him. Jack approached every one and asked if he had known Jack Shareburg. They all said no.

The churches he saw on his way through southwest France and northern Spain continued to astonish him. They were all much higher than the English cathedrals. Some of them had banded barrel vaults. The bands, reaching from pier to pier across the vault of the church, made it possible to build in stages, bay by bay, instead of all at once. They also changed the look of a church. By emphasizing the divisions between bays, they revealed that the building was a series of identical units, like a sliced loaf; and this imposed order and logic on the huge interior space.

He was in Compostela at midsummer. He had not known there were places in the world that were so hot. Santiago was another breathtakingly tall church, and the nave, still under construction, also had a banded barrel vault. From there he went farther south.

The kingdoms of Spain had been under Saracen rule until recently; indeed, most of the country south of Toledo was still Muslim-dominated. The appearance of Saracen buildings fascinated Jack: their high, cool interiors, their arcades of arches, their stonework blinding white in the sun. But most interesting of all was the discovery that both rib-vaulting and pointed arches featured in Muslim architecture. Perhaps this was where the French had got their new ideas.

He could never work on another church like Kingsbridge Cathedral, he thought as he sat in the warm Spanish afternoon, listening vaguely to the laughter of the women somewhere deep in the big cool house. He still wanted to build the most beautiful cathedral in the world, but it would not be a massive, solid, fortress-like structure. He wanted to use the new techniques, the rib-vaults and the pointed arches. However, he thought he would not use them in quite the way they had been used so far. None of the churches he had seen had made the most of the possibilities. A picture of a church was forming in his mind. The details were hazy but the overall feeling was very strong: it was a spacious, airy building, with sunlight pouring through its huge windows, and an arched vault so high it seemed to reach heaven.

“Josef and Raya will need a house,” Raschid said suddenly. “If you were to build it, other work would follow.”

Jack was startled. One thing he had not thought of building was houses. “Do you think they want me to build their house?” he said.

“They might.”

There was another long silence, during which Jack contemplated life as a housebuilder for wealthy merchants in Toledo.

Eventually Raschid seemed to come awake. He sat upright and opened his eyes wide. “I like you, Jack,” he said. “You’re an honest man, and you’re worth talking to, which is more than can be said for most people I’ve met. I hope we will always be friends.”