The charred scrolls of ancient Herculaneum may yet yield their secrets, suggests an x-ray analysis released Tuesday of one previously impenetrable roll of papyrus.
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.
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Conventional x-rays of the rolled-up Herculaneum scrolls don't reveal anything, says Seales, who is not an author of the current study. "What this study is reporting is a good first step," he says. "Down the road I think it will lead to a large number of scholars studying these scrolls."
Similar to a medical CT scan, the new process produced a three-dimensional view of the folded, compressed interior of the charred scroll. Unlike regular x-rays, the method can distinguish the charcoal ink from the surface of the charred papyrus.
Studying the interior surface of the scroll, the researchers demonstrated they were able to read letters, a few microns thick, written on the papyrus long ago. A first effort deciphered 24 letters used in ancient Greek, the language of philosophy in the Roman world.
"It will probably not be possible in the near future to really read [rolled-up] charcoaled papyri or similar objects, but with this technique one can certainly learn something new, and that is quite exciting," says x-ray expert Uwe Bergmann of the SLAC National Accelerator Laboratory in Menlo Park, California.
La Dolce Vita
A phrase read by the researchers from the study papyrus shows that this scroll, like most of the others, was likely written by a philosopher named Philodemus, an Epicurean thinker who advocated pleasure as a guide to a good life, setting him apart from the era's more stern Stoics.
Even seeing single Greek letters helps reveal how ancient sages did their stuff, says classicist Rebecca Benefiel of Washington & Lee University, in Lexington, Virginia. "You bet deciphering more of these scrolls would be helpful," she says.
Most likely, the study scroll contains an essay called "On Frank Criticism" by Philodemus, calling for honesty between friends, the researchers conclude based on their study of the scroll, which came from a collection in Paris.
The study researchers hope that the method leads to a non-destructive way to investigate more of Herculaneum's charred papyri, which in turn will reopen consideration of more excavation at the Villa de Papyri. Scholars have long pondered the possibility of another library buried deeper beneath its ruins.
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