X-rays illuminate ancient writings
Hidden Archimedes text comes to light in a physics lab.
An early transcription of Archimedes' mathematical theories has been brought to light through the probing of high-intensity X-rays.
The text contains part of the Method of Mechanical Theorems, one of Archimedes' most important works, which was probably copied out by a scribe in the tenth century. The parchment on which it was written was later scraped down and reused as pages in a thirteenth century prayer book, producing a document known as a palimpsest (which comes from the Greek, meaning 'rubbed smooth again').
Scholars discovered the text concealed in this book as early as 1906. Since then, much of the text has been read, using everything from magnifying glasses to ultraviolet light, which highlights the hidden ink.
But some of the text has been solidly obscured by some twentieth-century forgeries of medieval art that were slapped on top of a few pages. So researchers at the Stanford Synchrotron Radiation Laboratory in Menlo Park, California, decided to use X-rays to peer through this modern ink. Iron pigment in the original ink fluoresced when hit by the X-rays, allowing researchers to see the text for the first time.
"The Method is one of the most inventive and spectacular treatises of the greatest mathematician of antiquity," says William Noel, associate curator of manuscripts and rare books at the Walters Art Museum in Baltimore, Maryland, and director of the palimpsest project. "This information is not available anywhere else in the world."
The first page has now been scanned, but researchers have not yet been able to decipher the writing. Each scan yields a picture of the writing on both sides of each page, along with the thirteenth-century text that also lurks beneath the forged drawings. Different images will have to be compared carefully to unpick the Archimedes text.
Uwe Bergmann, a physicist at the synchrotron lab, says the technique is fairly straightforward, although he doesn't think it has been used to illuminate antique manuscripts before.
Alexander Jones, a classicist at the University of Toronto in Canada, thinks the technique could be useful in a wider context. "What we know about the Greco-Roman world depends very heavily on texts," he explains. "There are undoubtedly other damaged manuscripts to which this method could be applied."