The Herculaneum scrolls, first uncovered in the 18th century, were buried by the eruption of Mount Vesuvius in 79 AD that famously destroyed the Roman cities of Pompeii and Herculaneum. Consisting of a collection of 2 000 tightly wound scrolls, the eruption left them in a charred and fragile state. Previous efforts to read them have resulted in either extensive damage or full destruction. Using an instrument called a synchrotron accelerator that delivers x-ray beams 100 billion times brighter than anything used in a modern hospital, scientists at the European Radiation Synchrotron Facility realised that the scrolls were inscribed with metallic ink. The find is unexpected because until now scholars have depended on evidence left by the Roman historian Pliny the Elder that the Classical World used an ink made from smoke collected from wood furnaces. Pliny was himself one of the many victims of Vesuvius’ eruption. Making the discovery In January 2015, the research team used the accelerator to identify individual letters of the Greek alphabet and even whole words within the texts. Now they have gleaned that the papyrus scrolls contain high levels of lead that could only have come from its intentional use in the ink. The scientists came to this conclusion after they calculated that the levels of metal detected were too high to be explained by water contamination from the lead pipes used by the Romans, or from a copper inkpot or bronze container. ‘We found some metal – some lead – in the ink, which is supposed to come four centuries after [the eruption of Mount Vesuvius],’ commented Dr Emmanuel Brun of the European Radiation Synchrotron Facility. He continued: ‘The common belief is that the Romans introduced metallic ink in the fourth century.’ The findings, published in the journal ‘Proceedings of the National Academy of Sciences’ offers the opportunity to study the ink-and-paper technologies used during the Roman Empire’s zenith, as well as firmly establish the fact that the invention of metallic ink can be dated at several centuries earlier than previously thought. New opportunities for scholars Scholars can also now explore in further depth the handwriting of the ancient world and work towards being able to read ancient texts long considered lost. They can also explore the possibility of deciphering previously unknown and unread texts. ‘The discovery is interesting for the historical aspects but also for us for the papyrus scroll imaging,’ Dr Brun elaborated. ‘The different phases of the present study on the ink will allow us to optimise the next experiments on the reading of the invisible text within papyri.’ Out of 2 000 scrolls excavated from Herculaneum, around 600 remain unopened. Most the scrolls are philosophical works written in Ancient Greek, but other works include a comedy written in Latin. With these findings and the further refinement of the x-ray imaging methods pioneered in the study, it could soon be possible to decipher the remaining scrolls and considerably expand our understanding of the culture, literature and lifestyles of the Classical World.