X-Rays Image Fragile Scrolls

A machine that can generate light beams a million times brighter than conventional x-rays is being used to reveal the text of ancient documents, such as the Dead Sea Scrolls, considered too brittle to be read without destroying them.

The Dead Sea Scrolls are hundreds of ancient parchments first discovered in caves by the Dead Sea in 1947, where they had been hidden in clay pots and undisturbed for centuries. The scrolls contain texts from the Hebrew bible and originated sometime between the second century BC and the first century AD, scholars estimate. Many have been considered too fragile to be read since their discovery.

A scroll image created by researchers at Cardiff University in Wales. They are using powerful x-rays to reveal texts in ancient parchments too fragile to unroll or unfold, such as many of the Dead Sea Scrolls. (Image: Graham Davis and Tim Wess/Cardiff University)

Now researchers at Cardiff University's School of Optometry and Vision Sciences could provide the key to unlocking the secrets of those texts. Professor Tim Wess, head of the Institute of Vision at Cardiff University, has been working with the Diamond Light Source (DLS), a new scientific facility in Oxfordshire, England, and developed techniques to read written words on ancient documents without unrolling or unfolding them.

The DLS synchrotron is a powerful machine that fires electrons at close to the speed of light to generate synchrotron light in the form of x-rays, ultraviolet and infrared beams. Most of the experiments at the DLS, which opened in February, will use superbright x-rays. Researchers will use this intense synchrotron light to study a wide range of biological, chemical and material samples at the atomic and molecular level.

"Diamond will allow us to examine nanoscopic collagen structure in fragile and priceless parchments such as the Dead Sea Scrolls, to determine the advance of degradation without damage to the irreplaceable document," Wess said.

The facility will ultimately host up to 40 advanced research stations, called beamlines. Each beamline is designed primarily to support a particular research community or technique, such as life, physical and environmental sciences.

Wess and his team are the first users of the I22 noncrystalline diffraction beamline for the physical and life sciences. They are now working on the full-scale imaging and "virtual unrolling" of scrolls too fragile to open. The synchrotron x-rays can also be used to determine how fragile documents are, and how they should be preserved.

"In addition to identifying ways in which we might be able to prevent the loss of important records from both our past and future, our research aims to understand how we might recover documents damaged in natural disasters across the ages -- such as the fire at the Library of Alexandria, or more recently flooding in the Czech Republic, Italy and Poland, which could leave such archives lost forever," Wess said.

Historically significant documents such as the Dead Sea Scrolls, Domesday book, Magna Carta and the Declaration of Independence have survived environmental assault through the ages. However, the progressive degradation of the dried animal skins they are written on leaves them at risk.

Because ancient parchments were made from calfskin, sheepskin or goatskin, they contain collagen, which over time can degenerate into gelatine, which is brittle when dry but turns to jelly when wet. Wess and his team hope to use the DLS to examine the nanoscopic structure of the Dead Sea Scrolls, with the goal of developing a simple test to determine the proportion of gelatine in a historical sample.

The ink used to write ancient scrolls contains iron, which creates a "shadow" image on an x-ray. The researchers took numerous scans of parchments from different angles and were able to create a 3-D "unrolled" version of a document with 80 percent accuracy via computer, Wess said. Their research has also found that the mineral content of the Dead Sea Scrolls may have helped stabilize the collagen and slowed the scrolls' deterioration.

Documents currently being investigated by his team include some from national archives, such as 18th century scrolls damaged by fire, musical manuscripts thought to be written by Beethoven and Mozart, and postage stamp-sized fragments of the Dead Sea Scrolls.

Wess revealed his findings in a paper presented this week at the BA Festival of Science at York University, organized by the British Association for the Advancement of Science.

For more information, visit: www.cardiff.ac.uk