Tom was making the doorway of the house. The doorposts would be rounded to look like columns—a touch of distinction for the noble newlyweds who were to live here. With his eye on the shaped wooded 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 into 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.Continue this excerpt...

Read about how the Peterborough Cathedral inspired Ken Follett's work.

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