Message #13421

[Bianca]

Fragmentary Knowledge
by John Seabrook (page 5)


As Moussas and I headed uphill, toward the Acropolis, he pointed out the spot where Meton’s astronomy school and solar observatory had been. On our way back down, we stopped at the famous Tower of the Winds, the now gutted shell of what was the great central clock of ancient Athens. Designed by the renowned astronomer Andronicus of Cyrrhus, it is thought to have been an elaborate water clock on the inside and a sundial on the outside. “But, in light of what we know about the Mechanism,” Moussas said, “I am beginning to wonder whether this was a much more complicated clock than we think.”

When Derek Price died, of a heart attack, in 1983, his work on the Mechanism was unfinished. Although his fundamental insights about the device were sound, he hadn’t figured out all the details, nor had he succeeded in producing a working model that was correct in all aspects.

That year, in London, a Lebanese man walked into the Science Museum, on Exhibition Road, with an ancient geared mechanism wrapped in a handkerchief in his pocket. Michael Wright, one of the curators of mechanical engineering, was summoned to examine the artifact, which was in four main fragments. The man said that he’d bought the artifact in a street market in Beirut several weeks earlier. The Science Museum eventually bought it from him, and Wright and a colleague, J. Field, showed that it was a geared sundial calendar that displayed the positions of the sun and the moon in the zodiac. Wright also built a reconstruction of the sundial. The style of lettering on the dial dated the device to the sixth century A.D., making it the second-oldest geared device ever found, after the Antikythera Mechanism.

In addition to his job as a curator, Wright helped to maintain the old clocks exhibited in the museum. Among them was a replica of the oldest clock that we have a clear account of, constructed in the early fourteenth century by Richard of Wallingford, the Abbot of St. Albans. It was a fantastic astronomical device called the Albion (“All-by-One”). Another reconstruction was of a famous planetarium and clock built by Giovanni de’ Dondi, of Padua, in the mid-fourteenth century, known as the Astrarium. Like many students of mechanical history, Wright had noted this odd upwelling of clockwork in Europe, appearing in several places at around the same time. He was familiar with the theory that many of the elements of clockwork were known to the ancients. With the decline of the West, goes this theory, technical expertise passed to the Islamic world, just as many of the Greek texts were translated into Arabic and therefore preserved from loss or destruction. In the ninth century, the Banu Musa brothers, in Baghdad, published the “Book of Ingenious Devices,” which detailed many geared mechanical contrivances, and the tenth-century philosopher and astronomer al-Biruni (973-1048) describes a Box of the Moon—a mechanical lunisolar calendar that used eight gearwheels. The more Wright looked into these old Islamic texts, the more convinced he became that the ancient Greeks’ knowledge of gearing had been kept alive in the Islamic world and reintroduced to the West, probably by Arabs in thirteenth-century Spain.


from the issuecartoon banke-mail thisIn the course of this research, Wright became intensely interested in the Antikythera Mechanism. Upon studying Price’s account closely, he realized that Price had made several fundamental errors in the gearing. “I could see right away that Price’s reconstruction doesn’t explain what we can see,” he told me. “The man who made the Mechanism made no mistakes. He went straight to what he wanted, in the simplest way possible.” Wright resolved to complete Price’s work, and to build a working model of the Mechanism.

Whereas Price worked mainly on an academic level, approaching the Mechanism from the perspective of mathematical and astronomical theory, Wright drew on his vast practical knowledge of arbors, crown wheels, and other mechanical techniques used in gear-train design. His experience in repairing old grandfather clocks, many of which also have astronomical displays that show the phases of the moon, led him to one of his key insights into the engineering of the Mechanism. He posited that there must have been a revolving ball built in the front dial that indicated the phases of the moon—one hemisphere was black, the other white, and the ball rotated as the moon waxed or waned. Wright also showed how a pin-and-slot construction could be used to model the movement of the moon.

Wright, who is fifty-eight, has a British public-school demeanor, which is generally courteous and hearty and seemingly rational. But he is prey to dark moods, wild, impolitic outbursts, and overcomplicated personal entanglements—“muddles,” he calls them. Although he told me, “I really hate confrontation, and antagonism of any kind, even competition,” he consistently finds himself in disastrous confrontations with people who should be his allies. Whereas academic researchers are used to collaboration, and to sharing resources and insights, Wright is temperamentally more like a lone inventor, working away in secrecy and solitude until he has found the solution.

He did have a collaborator once—Allan Bromley, a lecturer in computer science at the University of Sydney and an expert on Charles Babbage, the nineteenth-century British mathematician who was the first to conceive of the programmable computer. Bromley used to come to the Science Museum to study Babbage’s papers and drawings and Wright would often lunch with him. In 1990, the pair took new X-rays of the Mechanism, the first since Price’s. But Bromley brought the data back to Sydney and would allow Wright to see only small portions of the material. (According to Wright, Bromley confessed “that he had it fixed in his mind that it would be his name, preferably alone, that would be attached to the ‘solution.’ ”)