October 14, 2021
Today we drove to the Ancient Roman city of Herculaneum which was buried under volcanic ash and pumice in the eruption of Mount Vesuvius in AD 79. The date of the eruption has been shown to be on or after 17 October. Support for an October/November eruption has long been known in several respects: buried people in the ash were wearing heavier clothing than the light summer clothes typical of August; fresh fruit and vegetables in the shops are typical of October – and conversely the summer fruit typical of August was already being sold in dried, or conserved form. Wine fermenting jars had been sealed, which would have happened around the end of October; coins found in the purse of a woman buried in the ash include one with a 15th imperatorial acclamation among the emperor’s titles and could not have been minted before the second week of September.
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 the death of people who had previously been thought to have died by ash suffocation. This study shows that exposure to the surges, measuring at least 250 °C (480 °F) even at a distance of 10 kilometres from the vent, was sufficient to cause the instant death of all residents, even if they were sheltered within buildings.
