Synchrotron X-ray fluorescence unveils Archimedes' hidden manuscript

Recently, a very old copy of Archimedes' writings, which had been erased, written over and even painted over during the past 1,000 years, has been analyzed by X-ray fluorescence with a sub-micron X-ray beam at Stanford Synchrotron Radiation Laboratory, California, United States. The palimpsest, which is preserved at Walters Art Museum in Baltimore, is a goatskin parchment on which a 10th-century scribe copied some of Archimedes' manuscripts originally written around 220 B. C. Later, the ink was erased by being scraped off with a pumice stone. Further damage was done when forgers painted Byzantine religious images on four pages. Archaeologists have successfully analyzed much of the 174-page palimpsest by conventional methods using visible and ultraviolet light, but several pages, including those under the paintings, remained obscured. The main idea behind the work at Stanford is that the ink contains iron pigment, and therefore the analysis is basically the mapping of iron K X-ray fluorescence. As the ink is only 1-2 microns thick, the use of a sub-micron beam was crucial. The analysis revealed that the hidden text on two of the pages is about floating bodies and the equilibrium of planes. Surprisingly, the third page is a previously unknown introduction to Archimedes' Method of Mechanical Theorems. The main source of the news is an article by Heather Rock Woods, Stanford University,http://news-service.stanford.edu/news/2005/may25/archimedes-052505.html
For further details, contact Neil Calder, Stanford Linear Accelerator Center, Phone +1-650-926-8707, or Uwe Bergmann, Stanford Synchrotron Radiation Laboratory, Phone +1-650-926-3048, bergmann@SLAC.Stanford.EDU