The owner of the store told Saff the clock was too damaged to ever be restored. But Saff was persuasive; he was sure he could fix it. He took home the clock that day—and unknowingly set the wheels in motion for a renaissance of Harrison’s clock-making science, dismissed and ignored for 300 years.

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Martin Burgess, who made Saff’s clock, lives 3,500 miles from New York on a rural plot of land in Essex, England. He is a clockmaker trained by blacksmiths, a restorer of Egyptian antiquities, and one of the foremost experts on chainmail in the U.K., if not the world.

In the 1950s, in a bookstore in London, Burgess bought a biography of Harrison, who is best known for inventing the chronometer, or sea clock. In 1714, Queen Anne of England passed the Longitude Act, offering a £20,000 prize (roughly $3 million today) to anyone who could devise a way to calculate longitude at sea; without it, British trade ships were losing lives and precious cargo. As Dava Sobel documented in her book Longitude, Harrison was able accomplish the task with a clock called H4. Besides for allowing sailors to calculate how far east or west they had traveled, the clock was extremely accurate, losing only 39.2 seconds over a 42-day voyage.

But in the years before he created his marine timekeepers, Harrison made precision pendulum clocks, also known as regulators. At the time, George Graham, the period’s most prominent clockmaker, was building clocks that were accurate to a second per day. Harrison, who was trained as a carpenter, not a clockmaker, made clocks almost entirely out of wood; according to Harrison, they were so accurate that they changed by only a second a month, far better than any other clock being made for use on land or sea. But he believed that he could do even better: By using his theories, Harrison claimed, it would be possible to make a clock with an error of one to two seconds per year.

Harrison left behind three manuscripts about his methods. The most important, published a year before his death, is titled: A Description concerning such mechanism as will afford a nice, or True mensuration of time. As the name suggests, the language is dense and convoluted. The contemporary British clockmaker George Daniels has called the text “rubbish”; Rupert Gould, the author of the biography Burgess read, described it as “gibberish.”

Burgess disagreed.

“Everybody said, ‘That’s a lot of nonsense,’” Burgess said. “‘Second to the month? No. Those things couldn’t possibly.’ Well, I was pretty sure they did.”

Burgess and another horologist, William Laycock, began to study Harrison’s writing more closely, and then to advocate for his theories within the horological community. In 1976, the two delivered a lecture to the British Horological Institute arguing for the validity of Harrison’s ideas, but they were generally dismissed—except by a few. In the audience was the engineer Mervyn Hobden. He had never met Burgess. But after the lecture, Hobden said, he felt compelled to approach him.