When Mount Vesuvius, on the west coast of Italy, first began its volcanic rumblings in A.D. 79, ash and white pumice deluged the surrounding region, including the famous city of Pompeii. Several hours later, the volcano belched up another phase of its eruption: a series of steaming toxic clouds of gas and rock, called pyroclastic surges, that heaved down the mountainsides, engulfing Pompeii and the nearby seaside town of Herculaneum.
Most residents of Herculaneum had time to flee—but not all. Some 340 people perished in the town’s beachside boathouses and on the beach itself.
How these unlucky souls died has been a mystery. The dominant theory, first proposed in 2001, suggests that they succumbed instantly to heat shock, and that the surge was so intense, their blood boiled and their flesh vaporized.
But not everyone agrees. “The reality is that soft tissue does not instantly vaporize at any temperature,” says Tim Thompson, a biological anthropologist at Teesside University in the U.K. “I think there’s a general consensus among those who work on bone and remains that vaporization just doesn’t happen.”
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In a new study, published this week in the journal Antiquity, Thompson and his colleagues offer a new analysis and theory as to how these people died—one that may change how we picture this iconic episode. The techniques they used are part of an emerging set of tools that allow anthropologists to investigate human remains exposed to high heat—as in cremation, for example—at an unprecedented level of detail.