National Geographic's Dan Vergano
describes how the lava-charred scrolls of ancient Roman Herculaneum are starting to be read through careful use of X-rays.
The volcanic Mount Vesuvius erupted in 79 A.D., destroying the wealthy Roman resort town of Herculaneum along with the better-known Pompeii. Only some 260 years ago did explorers at Herculaneum first uncover the roughly 800 charred scrolls from a library in a building dubbed the "Villa de Papyri," buried beneath more than 50 feet (15 meters) of ash.
While hundreds of the scrolls have been painstakingly unwrapped since then, with some destroyed in the process, most remain too fragile to unroll and read. But a new x-ray technique reads the text right through the rolled-up papyrus, reports a team led by Vito Mocella of the Institute for Microelectronics and Microsystems of the National Council of Research, in Naples, Italy, by discerning charcoal ink from charred papyrus.
"This pioneering research opens up new prospects not only for the many papyri still unopened, but also for others that have not yet been discovered," the team reports in the journal Nature Communications.
The x-ray technique, called phase-contrast tomography, can read the letters on a rolled-up fragment of a scroll that suffered the 608°F (320°C) heat of the ash avalanche that buried the town. The deciphered letters most likely were written in the century before the destruction of the resort.
The scrolls undergo the equivalent of a chest x-ray, which doesn't do much damage, says computer imaging expert Brent Seales of the University of Kentucky, in Lexington, who is on the larger team that for years has sought to peer inside the Herculaneum scrolls. "The real worry comes from handling them; they are very delicate," he says.