Much of what we know about the eruption of Vesuvius in 79 AD we know through the writings of Pliny the Younger. The younger Pliny was a young man when Vesuvius erupted — only 18 years old. His father had died when the boy was quite young, but he had been well-educated, first at home and later in Rome. In Rome, he got to know his uncle, Pliny the Elder, with whom he became quite close.
No one was really expecting any significant activity from the volcano. It had been considered dormant for hundreds of years, and was covered with farms and vineyards. There had been serious eruptions in the past, but that was thousands of years before Pliny’s time and had become the stuff of legends. From time to time there was a minor earthquake, certainly, but that served more to reassure the local residents than to disquiet them. As Pliny the Younger wrote to a friend, the tremors “were not particularly alarming because they are frequent in Campania.”
It was the middle of the day when the volcano first exploded, throwing a column of smoke and ash into the air. Pliny the Younger compared it to a pine tree — he meant the stone pine of the Mediterranean region, which has an umbrella-like top of branches on top of a very tall trunk. The column was variegated in color, showing bright and dark areas which were probably the effects of cinders and earth.
The elder Pliny, who was prefect of the Roman Navy, received a message asking for help in evacuating from a friend in Herculaneum, where the only route out of the city would be by sea. (We aren’t told how the messenger got out of the city.) He immediately took his fleet and set off for Herculaneum.
When he approached the city, the thick rain of cinders and rock prevented him from approaching the city, so he set off for Stabiae instead. He had another friend in Stabiae, Pompianus, who had already loaded up a ship with his possessions and was preparing to leave the city. Neither Pompianus nor anyone else was able to leave, however. A strong wind coming in from the bay — the same wind which had brought Pliny there — was preventing anyone from leaving.
The party returned to the village, and Pliny was even able to sleep that night — his comrades later remarked on his snoring. When the building that Pliny was staying in threatened to become blocked with debris, his party awakened him, and they set off for the fields, with pillows tied over their heads to protect them from what was falling from the heavens. At one point, they sat down to rest for awhile, and when they were ready to move on Pliny was unable to get up, even with his friends’ assistance. The party moved on without him.
Pliny the Younger believed that his uncle had been overcome with poisonous gases, but, since the others of the party were unaffected, this seems unlikely. However, Pliny was fat and subject to asthma, so he may have been more vulnerable. It is also possible, and perhaps more likely, that he suffered a stroke or heart attack. It is unlikely that his friends would have abandoned him if he had still been alive.
It is unknown how many people died in the 79 AD eruption of Vesuvius, but it is known that the cities of Pompeii, Herculaneum, and Stabiae were destroyed. In Pompeii, 1,044 casts have been made from the depressions of bodies in the ash, and the scattered bones of another 100 or so victims have been found. Another 332 bodies were found in Herculaneum. Pompeii was by far the largest of the three towns; it is estimated that it may have had a population as large as 20,000.
It is thought now that most of the deaths were caused, not by suffocation, but by the intense heat of the event. It has been estimated that heat waves of up to 250 degrees Celsius (482 degrees Fahrenheit) could have been found at distances of 10 kilometers from the vent. A temperature that extreme would likely cause instant death, even for people huddled indoors. Other studies have indicated that the first heat surge at Herculaneum could have reached 500 degrees Celsius (932 degrees Fahrenheit.)
The first discovery of the ruins of Pompeii took place in 1599, by an architect digging a channel to divert the Sarno River. He found a few frescoes, which he considered shockingly sexual in subject matter, and promptly covered them up again. The city was rediscovered in 1738 during the construction of a summer palace for Charles of Bourbon. The first serious excavations began in 1764.
In the 1860’s, it was discovered that in many of the ash deposits where human remains had lain there were pockets in the ash layer. The archeologist Giuseppe Fiorelli was the first to realize that these had been the places where flesh had decomposed, and he devised a technique for injecting plaster into the hollows, perfectly recreating the forms of the dying citizens. A similar technique is still used today, but with silicon instead of plaster.
Herculaneum also netted a significant archeological find: the skeletons of the victims. Because of the intense heat, the flesh was practically vaporized, leaving the skeleton behind. Since the Romans tended to cremate their dead, these remains provide some of the very few Roman skeletons that are available for study, and provide information on the inhabitants of Herculaneum. (They suffered from lead poisoning, for one thing.)
Other victims at Herculaneum were found along what was then the coast, and seem to have died of shock, but were not vaporized. Their death was not quick; many of the victims clearly died in agony. Most of these remains were found in structures that are believed to have been boathouses. No remains of boats were found — apparently other Herculaneum residents had already taken them.
Since 79 AD, Vesuvius has erupted over 30 times. Some of them were significant: in 472 ashes fell as far away as Constantinople, and 512 the devastation was great enough that those that lived there were given exemption from taxes.
By the end of the 13th century, the volcano was quiet enough that its slopes were once more covered with vineyards and farms. Then came 1631, when 3,000 people were killed by lava flows and boiling water. After that, eruptions happened at least several times every century. The most recent eruption was in 1944.
Today about three million people live within 12 miles of Vesuvius. About 600,000 of them are crammed into la zona rossa, the “red zone.” In some places the population density is as high as 30,000 per square kilometer, higher even than Hong Kong. The current evacuation plan assumes that there would be between two weeks and 20 days advance warning of an eruption, and that 600,000 people could be transported by car, train, bus, or ferry within seven days — through narrow, winding, and often congested roads.
The government is also seeking to decrease the population of the red zone. Illegally constructed buildings are being demolished, and a national park has been established around the upper regions of the volcano in order to prevent further construction there. The government has also offered financial incentives to people who move out of the area.
Naturally, the volcano is closely monitored, both in terms of ground movement and in the chemical composition of gases being emitted. To date, no magma has been discovered to be less than 10 kilometers from the surface. Vesuvius is currently at rest.
Sources: Chase’s Calendar of Events, 2011 Edition: The Ultimate Go-To Guide for Special Days, Weeks, and Months, Editors of Chase’s Calendar of Events; http://en.wikipedia.org/wiki/August_24; http://en.wikipedia.org/wiki/Mount_Vesuvius; http://en.wikipedia.org/wiki/Pliny_the_Younger; http://en.wikipedia.org/wiki/Pliny_the_Elder; http://www.gutenberg.org/cache/epub/2811/pg2811.html; http://www.archaeology.co.uk/cwa-2/world-features/visiting-pompeii.htm; http://en.wikipedia.org/wiki/Pompeii; http://en.wikipedia.org/wiki/Herculaneum; http://en.wikipedia.org/wiki/Stabiae; Bill McGuire, “In the Shadow of the Volcano,” Guardian.co.uk; Christian Fraser, “Vesuvius Escape Plan ‘Insufficient,’” BBC News.