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A Closer Look at Ancient Documents

12/03/08
The USC Archaeological Research Center has studied the Dead Sea Scrolls for more than two decades – and their technology remains unparalleled.
By Lauren Walser
Bruce Zuckerman, USC College professor of religion and director of the USC Archaeological Research Center

Photo/Dietmar Quistorf
It feels impolite to call them “small dinky things” or “smashed mushrooms.” But researchers in the USC archaeology labs said as much. And pressed onto a piece of glass while undergoing intense photography, those descriptions do not seem far off.

Technically, they’re called Dead Sea Scrolls. And for a single day in November, researchers in the USC Archaeological Research Center had five “dinky” fragments of the scrolls in their hands. But the researchers saw this day as more than just a chance to unlock new clues to these ancient texts. It was an opportunity to test out some of the most high-tech equipment in the field using techniques only available in their labs at USC.

The Dead Sea Scrolls have long been artifacts of intense scholarly and public interest – as well as heated debate. In 1947, young Bedouin shepherds stumbled upon a cave full of jars containing ancient scrolls. This discovery led to an ongoing search that has produced thousands of tiny fragments of biblical and early Jewish documents, dated from the third century BCE (before the common era) to the second century C.E. – including documents nearly a thousand years older than any other surviving manuscript of the Hebrew Scriptures.

It’s a rare opportunity for scholars to have these documents available to them, but the researchers in the Archaeological Center have been working with these scrolls for more than 20 years – longer than any other group of scholars.

“If someone wants the best images of the Dead Sea Scrolls, they know to come to us,” said Bruce Zuckerman, USC College professor of religion and director of the USC West Semitic Research Project and the Archaeological Research Center.

And this time around, new photographic equipment made their acquisition of Dead Sea Scroll fragments all the more exciting.

“What we especially wanted to do this time was see if this equipment would work the way we expected it to,” Zuckerman said. “It wasn’t certain that this would be the case. No one had ever tried these techniques before.”

But their results were astounding. “The images we captured are far better than anything we’ve ever seen before,” Zuckerman said. “We were able to pick up details we didn’t expect to see.”

The process was a slow one. First, the researchers scanned the image under two different lighting conditions – visible light and a narrow band of infrared light. The latter brings out the contrast between the skin and the ink. Over time, the ink becomes obscured as the skins darken so that the surfaces appear totally black to the naked eye. But under the infrared light, the skin becomes highly reflective, and the ink reappears.

Then the fragments were taken to a light dome. Or, as Zuckerman calls it, “the Ollie dome.” (“It looks like Oliver Hardy’s hat,” he explained.) This spherical machine holds an array of 32 lights allowing for 32 pictures to be taken, each from a slightly different light angle.

Through a special software algorithm called polynomial texture mapping, the researchers were able to capture the most minute details of the scrolls’ fabric, such as the hair follicle patterns of the skins. This imaging may allow researchers to identify the types of animals whose skins were used, which then will help them piece the fragments together.

Once the scanned images were uploaded on their computers, the researchers got to work. Using the computer mouse as a narrowly focused light source, researchers were able to control the intensity and the positioning of the light by moving the mouse around, revealing detailed information about the types of skin used and the writing they contain.

The speculation began: Is this a piece of Leviticus, the third part of the Torah? Or is this part of a commentary on the Torah, as many of the Dead Sea Scrolls are?

“Imaging like this is literally better than standing in front of the piece looking at it,” explained Ashley Sands ’07, who got her first taste of archaeology as a freshman in one of Zuckerman’s classes and continues to work for his lab.

When comparing these new techniques to their previous methods, it is apparent just how far the USC archeology lab has come.

In the past, the researchers used infrared film to examine the scrolls, which produced grainy, washed-up images. And DNA sampling, which previously was the only way to identify the types of animal skins used, is a difficult and time-consuming process that ends up destroying the original sample.

“This is such a quantum leap over our old methods,” Zuckerman said. “At this level, we’re even able to see how the ink falls into grooves in the skin. We never could see this until we had this technology.”

The implications of their discoveries are broad. These new techniques will help researchers as well as conservation experts who preserve and archive the artifacts.

Polynomial texture mapping imagery also has enabled historians studying medieval illuminated manuscripts to see the actual brushstrokes on the pages for the first time.

“And this is just the beginning,” Zuckerman said. “I expect we’ll be using these methods in ways we haven’t even thought of yet.”