X-RAYS GIVE GLIMPSE OF PAST : NASA TECHNOLOGY HELPS ARCHAEOLOGISTS DISCOVER JAMESTOWN.

Byline: Mark St. John Erickson Newport News Daily Press

Elliot Jordan stands in a small, darkened room peering at the cluster of X-rays hanging on the wall.

``Lots of surprises,'' the archaeologist says, pushing his nose up close to one of the glowing pictures.

Only a few minutes before, Jordan and fellow conservator Michael Lavin had started to unbox dozens of mysterious, rust-colored lumps found at the site of the first permanent English settlement in the New World.

Working under the watchful eye of NASA engineering technician Bob Berry, they arranged the puzzling clods under the lens of an industrial X-ray machine at Langley Research Center's non-destructive evaluation radiographic lab. Soon, the first sheets of film were spitting out of the developing machine and slapping into a wire hopper. From there, they went to the gleaming white surface of the fluorescent lightbox, where Jordan, Lavin and Berry smiled broadly as the secrets of the hidden artifacts unfolded.

Instead of rusty blobs, the X-rays turned up a handwrought hinge, a box lock, a hasp and a gang mold used for pouring lead musket balls. They also uncovered a cauldron leg, a knife handle and a saw-toothed strap used for hanging kettles over a fire.

``This is much better than going to a lot of trouble for something that's not much more than a big block of nails,'' says Lavin, who performs most of the iron conservation work for the Jamestown Rediscovery project.

``It can take a week just to clean one bag of these things - and then you find out it's something that's not worth cleaning.''

No one knows exactly how much work the NASA X-rays have saved the archaeologists at Jamestown.

Using the pictures as a guide, they cut the time needed to clean an iron breastplate to around 100 hours, Lavin says.

Over the past 2-plus years, the scientists have brought dozens of promising yet ambiguously shaped lumps of rusty clay to Berry's lab, hoping to avoid the tedium and risk of doing their work unaided.

The objects have ranged from slender bridle bits to broad axheads, and they include such significant finds as the breastplate and a cabasset helmet.

``Some of them we think we know before we come down here, and some of them we have no idea,'' Jordan says.

``It lets you know right off the bat what you're working with.''

The highly detailed pictures also help the archaeologists determine the smartest methods for conserving the often fragile pieces of iron.

Using equipment designed to ferret out design and manufacturing flaws in aircraft and space flight hardware, they can identify weak areas that need special treatment. And they can weigh the benefits of cleaning an extremely rare artifact by hand or with such laboratory techniques as electrolysis.

``But you'd probably lose part of it if you did because of the extensive corrosion.'' No ordinary medical X-rays could provide enough detail to make such delicate judgments. The fine and extra-fine grade film used here is about 10 times more sensitive than that normally used in hospitals, Berry says.

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Photo: Archaeologist Elliott Jordan and Bob Berry, a Langle y technician, look at X-rays of iron artifcats from the Jamestown, VA., settlement.

Knight-Ridder Tribune Photo Service