Palimpsest reveals new knowledge of old past

Guardian : Thousands of books were lost, burned, or scattered during the upheaval of Europe’s Dark Ages. Among those missing books were treatises by some of the earliest mathematicians, such as Archimedes. But some of the material is now being rediscovered with the use of modern technology.Centuries ago parchment was expensive, so scribes would frequently reuse pieces by scratching out the old text and replacing it with new. It was discovered years ago that a 13th century Byzantine prayer book was actually composed of several earlier, overwritten manuscripts—one of which contained several treatises by Archimedes that were copied in 10th century Constantinople. As Physics Today reported 10 years ago, by illuminating the manuscript with specific wavelengths of light and by applying intensive data analysis to the scattered images, the original wording can be recovered.Besides Archimedes’ treatises, the prayer book also contained speeches by the classical Athenian orator Hyperides and a lost commentary on Aristotle’s Categories.The so-called Archimedes Palimpsest is on display through 1 January 2012 at the Walters Art Museum in Baltimore, Maryland, and next week Cambridge University Press is publishing a two-volume book on the subject.