The Crystal Sun

Archaeologists have always insisted most strenuously that lenses did not exist in ancient times. Robert Temple's real-life detective story proves them wrong. His research began with the discovery that an ancient artifact in the British Museum, believed to be a piece of rock crystal, had, in fact, been ground to form a lens.
In this fascinating book, one of the most revolutionary studies in the history of science and civilization to be published for decades, Robert Temple reconstructs the story of light technology in ancient civilization. Dating back at least to 2600 BC to Old Kingdom Egypt, but unknown to modern archaeologists and historians, a science of optics and a sophisticated technology for the manufacture of lenses was widespread and fundamental in ancient times. It inspired awe in cultures who used it, so became encoded in their mythologies and religions.

"From the Paperback edition.