Featured Artifact the Burnt Herculaneum Scroll Read
When Mt. Vesuvius erupted in A.D. 79, it destroyed a library of classical works in Herculaneum. The papyrus scrolls weren’t incinerated, but were instead carbonized by the hot gases. The resulting black carbon cylinders have mostly withstood attempts to read their contents since their discovery. Earlier attempts to unfurl the scrolls yielded some readable material, but were judged too destructive. Researchers decided to wait for newer technology to be invented that could read the scrolls without unrolling them.
Now, a team led by Dr. Vito Mocella from the National Research Council’s Institute for Microelectronics and Microsystems (CNR-IMM) in Naples, Italy has managed to read individual letters inside one of the scrolls. Using a form of x-ray phase contrast tomography, they were able to ascertain the height difference of about 0.1mm between the ink of the letters and the papyrus fibers, which they sat upon. Due to the fibrous nature of the papyrus and the carbon-based ink, regular spectral and chemical analysis had thus far been unable to distinguish the ink from the paper. Further complicating the work, the scrolls are not in neat cylinders, but squashed and ruffled as the hot gases vaporized water in the papyrus and distorted the paper.
Hundreds of papyrus rolls, buried by the eruption of Mount Vesuvius in 79 AD and belonging to the only library passed on from Antiquity, were discovered 260 years ago at Herculaneum. These carbonized papyri are extremely fragile and are inevitably damaged or destroyed in the process of trying to open them to read their contents. In recent years, new imaging techniques have been developed to read the texts without unwrapping the rolls. Until now, specialists have been unable to view the carbon-based ink of these papyri, even when they could penetrate the different layers of their spiral structure. Here for the first time, we show that X-ray phase-contrast tomography can reveal various letters hidden inside the precious papyri without unrolling them. This attempt opens up new opportunities to read many Herculaneum papyri, which are still rolled up, thus enhancing our knowledge of ancient Greek literature and philosophy.
The catastrophic eruption of Mt. Vesuvius occurred on the afternoon of 24 August 79 AD. Because Vesuvius had been dormant for approximately 800 years, it was no longer even recognized as a volcano. Based on archaeological excavations and on two letters of Pliny the Younger to the Roman historian Tacitus, the course of the eruption can be reconstructed.
At around 1pm on 24 August, Vesuvius began spewing volcanic ash and stone thousands of meters into the sky. When it reached the stratosphere, the top of the cloud flattened, prompting Pliny to describe it to Tacitus as a Stone Pine tree. The prevailing winds at the time blew toward the southeast, causing the volcanic material to fall primarily on the city of Pompeii and the surrounding area. Since Herculaneum lay to the west of Vesuvius, it was only mildly affected by the first phase of the eruption. While roofs in Pompeii collapsed under the weight of falling debris, only a few centimeters of ash fell on Herculaneum, causing little damage but nonetheless prompting most inhabitants to flee.
During the following night, the eruptive column, which had risen into the stratosphere, collapsed onto Vesuvius and its flanks. The first pyroclastic surge, formed by a mixture of ash and hot gases, billowed through the mostly evacuated town of Herculaneum at 100 mph. A succession of six flows and surges buried the city’s buildings, causing little damage and preserving structures, objects and victims almost intact.
Recent multidisciplinary research on the lethal effects of the pyroclastic surges in the Vesuvius area showed that in the vicinity of Pompeii and Herculaneum heat was the main cause of death of people, who were heretofore presumed to have died by ash suffocation. This study shows that exposure to at least 250 C hot surges even at a distance of 10 kilometers from the vent was sufficient to cause the instant death of all residents, even if they were sheltered within buildings.