'Decoding the Heavens' by Jo Marchant

A friend and I can't discuss archaeology without arguing over the greatest wonder of the ancient world. Is it the crypt of Seti I in the Valley of the Kings, whose grandeur dwarfs the modest resting place of Tutankhamen? No, surely it's the tomb of Qin Shi Huangdi, with its thousands of life-size terra cotta infantry. But what about the ruins of Palenque or Great Zimbabwe? Yet can they compare with Angkor Wat or the Colosseum?

After reading Jo Marchant's marvelous first book, "Decoding the Heavens," I may find myself arguing that our greatest legacy of the past might actually be -- instead of yet another shrine to hubris -- a toaster-size technological memento of just how intelligent some ancient thinkers could be. The very conception of the artifact that experts call the "Antikythera device" is outrageous, aside from its brilliant engineering. Both points deserve emphasis. We may wonder why, for example, the islanders of Rapa Nui sculpted giant heads out of volcanic tuff, but the concept itself doesn't baffle us. There are plenty of unsolved historical mysteries, but most are along the lines of the opaque cipher of the 15th century Voynich manuscript. Few archaeological artifacts compel experts to ask one another, "What exactly is that thing, and how on earth did some ancient whiz kid think of it, much less produce it?"

In her busy, elegant narrative, Marchant asks this question about the Antikythera device -- and, more impressively, she answers it. She reported, in the pages of Nature in 2006, what appears to be the solution to the mystery: how the device's intricate gear systems tracked the different cycles of the sun and moon and the few planets known to the ancient Greeks, as well as the four-year Olympiads. Marchant is not the first person to write about the device, of course. It shows up in most books about ancient technology, alongside diagrams of the mechanical singing birds of Crete and the possibility that the Nazca of Peru invented the first passenger balloons. But until recent technical advances, such as the microfocus X-ray imaging that enabled researchers to literally peer inside the corroded bronze fragments, one hidden layer at a time, scientists were often working with too little data and too much inference -- and, in some cases, a strong leaven of arrogance. Marchant's account is the most up-to-date and the first to document the full story, exploiting discoveries that occurred as recently as 2008.