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Refugees trying to shelter from Vesuvius were fried alive by volcanic ash

By David Derbyshire, Science Correspondent

AFTER 12 hours huddled in the beachside boat houses, the refugees from Herculaneum had probably assumed that the worst was over.

Vesuvius had been erupting all day and, apart from the hail of pumice, there seemed to be no obvious danger. Yet as the 300 men, women and children sat in the semi-darkness debating whether to return to their homes or flee down the coast, a scorching cloud of superheated volcanic ash burst into the crowded shelters. They were instantly fried alive.

More than 1,900 years later archaeologists have learnt how some of the townsfolk died. In Nature today they report on an analysis of 30 skeletons excavated in the 1980s and 1990s.

The people of Herculaneum were unaware that their town, a resort for wealthy Romans, was in the shadow of an active volcano. Vesuvius had not erupted for centuries and the series of earthquakes 17 years before had not been linked to it.

Then, in 79AD, explosions began the best-documented eruption of antiquity. For 12 hours, according to Pliny, the volcano sent up a column of ash and hot gas and hurled out hot stones and pumice.

Most of the 4,000 to 5,000 inhabitants appear to have evacuated the city. Since the first excavations in the 18th century, few bodies have been found in Herculaneum. Many fled to the beach, probably to escape by boat. Others waited in 12 boat huts, each about 100ft square.

The study of their remains shows that the column of gas and ash from the volcano collapsed, sending a 500C pyrosclastic surge through the town and to the waterfront. The cloud dropped down the 60ft cliff and blasted the shelters.

The relaxed postures of the skeletons suggest that they died instantly from heat shock and not suffocation. The hot cloud vaporised their flesh and then covered their remains with volcanic ash.

A team led by Dr Alberto Incoronato, of the University of Naples Federico II, studied 80 skeletons taken from ash that had solidified. These showed no signs of a "voluntary self-protective reaction or agony contortions, indicating that their vital organs must have stopped within a shorter time than the conscious reaction time. The cloud was a mixture of hot gas and ash," he said yesterday. "It caused little damage in the town itself but killed these people instantly."

The position of the victims suggested that the ash expanded slightly and then deflated, becoming denser and smothering the remains. Some people had fractures and holes blown into their skulls by the heat. The patterns of cracks in tooth enamel and patterns in the bones suggest 500C temperatures.

Dr Pier Petrone, a co-author of the study, said: "It is the first time that there is the possibility to study a group of people who did not die from illness or age. It is a cross section of a living population." The victims were mostly young adults or children and babies, he added. The boat chambers were crowded, with one containing more than 40 skeletons.

Herculaneum was a favoured holiday destinations of Romans. Merchants and landowners often had second homes in the shadow of Vesuvius. Most workers in the towns were employed in agriculture, fishing or trade industries.

-- Anonymous, April 12, 2001