Eureka! Unlocking Archimedes' ancient text
Causing invisible ink to glow
BALTIMORE, Maryland (AP) -- A particle accelerator is being used to reveal the long-lost writings of the Greek mathematician Archimedes, work hidden for centuries after a Christian monk wrote over it in the Middle Ages.
Highly focused X-rays produced at the Stanford Linear Accelerator Center in Menlo Park, California were used last week to begin deciphering the parts of the 174-page text that have not yet been revealed.
The X-rays cause iron in the hidden ink to glow.
"One of the delightful things is we don't know what it's going to say," said William Noel, head of the Archimedes Palimpsest project at the Walters Art Gallery in Baltimore.
Scholars believe the treatise was copied by a scribe in the 10th century from Archimedes' original Greek scrolls, written in the third century B.C.
It was erased about 200 years later by a monk who reused the parchment for a prayer book, creating a twice-used parchment book known as a "palimpsest." In the 12th century, parchment -- scraped and dried animal skins -- was rare and costly, and Archimedes' works were in less demand.
The palimpsest was bought at auction for $2 million in 1998 by an anonymous private collector who loaned it to the Baltimore museum and funded studies to reveal the text. About 80 percent of the text has been uncovered so far.
"It's the only one that contains diagrams that may bear any resemblance to the diagrams Archimedes himself drew in the sand in Syracuse 2000 years ago," Noel said.
Enter: the particle accelerator
While reading an article on the text, Stanford physicist Uwe Bergmann realized he could use a particle accelerator to detect small amounts of iron in the ink. The electrons speeding along the circular accelerator emit X-rays that can be used to cause the iron to fluoresce or glow.
"Anything which contains iron will be shown, and anything that doesn't contain iron will not be shown," Bergmann said.
Bergmann normally uses the accelerator, in which electrons are pushed to near the speed of light, to study the structure of water, and how water is split to create oxygen during photosynthesis.
Most of the text has been revealed by scientists at Johns Hopkins University and the Rochester Institute of Technology who used digital cameras and processing techniques as well as ultraviolet and infrared filters developed for medicine and space research.
The so-called Archimedes Palimpsest includes the only copy of the treatise "Method of Mechanical Theorems," in which Archimedes explains how he used mechanical means to develop his mathematical theorems. It is also the only source in the original Greek for the treatise "On Floating Bodies," in which Archimedes deals with the physics of flotation and gravity.
Three of the undeciphered pages were imaged last week, and the rest are expected to take three to four years to complete, Noel said.
Scientists at the Stanford Linear Accelerator Center in Menlo Park, California are analyzing a 174-page text.  The book had originally contained a copy of Archimedes' writings, but had been erased by a monk in the 12th century and reused as a prayer book.  The particle accelerator is able to see small iron particles that were present in the original ink.

The book is believed to have been originally copied from Archimedes' 3rd century BC Greek scrolls.  About 80 percent of the text has been recovered, showing diagrams that may more closely resemble Archimedes' original work than has ever been seen before.  The palimpsest includes "Method of Mechanical Theorems", a treatise that had been thought lost.  In it, Archimedes describes his use of mechanics to establish his mathematical theorems.  The palimpsest also includes the only original Greek version of "On Floating Bodies", which explains the physics of gravity and flotation.

It is projected that it may take three to four years to complete imaging of the book.