24th August: Mount Vesuvius

On this day in 79 AD, Mount Vesuvius Erupted destroying Pompeii and Herculaneum. Here are 10 facts about the event.

1. It seems rather coincidental that the disaster happened the day after Vulcanalia, the Roman festival to honour Vulcan, the god of volcanoes and fire (August 23). At this festival, people would build bonfires and sacrifice small animals to protect their crops from forest fires. No doubt the disaster would have suggested to the survivors that Vulcan had been extremely unimpressed with the previous day's sacrifices. The Emperor Domitian (who ruled from 81-96 A.D.) must have thought so, because he built a new altar to Vulcan on the Quirinal Hill and introduced the sacrifice of a bull-calf and a red boar to the sacrifices made on the Vulcanalia.
2. At least, historians have assumed it happened on this date because Pliny the Younger, who wrote the only surviving eyewitness account of the disaster, dated his letter "nonum kal. Septembres" which was interpreted as meaning "the ninth day before the Kalends of September", or eight days before September 1, i.e. August 24.
3. However, "nonum kal. Septembres" wasn't the standard way of writing the date, and more recently, the actual date of the eruption has been questioned by archeologists, who noticed that the victims were wearing warmer clothing than would have been expected in August, and the produce found stored in Pompeii (fresh Olives and dried fruit) suggested it actually happened in October. Further evidence came from the study of weather patterns - the prevailing winds in the area in August would have resulted in different patterns of ash fall. Also, a commemorative coin, which would not have been minted until late September, was found in the purse of one victim.
4. Had the residents of Pompeii had the scientific knowledge we have today, they would have known something was wrong because of the increased number of Earthquakes prior to the eruption. As it was, earthquakes were just a normal part of life for them and they would simply patch up any damage and carry on. Today, volcanologists are constantly monitoring the seismic activity and are confident they would be able to give several months' warning of an eruption on that scale.
5. According to legend, many years before the eruption, Hercules passed through the area while performing his labours. It was described as a "plain of fire" and the volcano as "a hill which anciently vomited out fire". Hercules pacified the giant bandits who lived there before moving on. It's possible that Herculaneum, the other town decimated by the eruption, was named after this legend.
6. The eruption released a hundred thousand times the thermal energy released by the Hiroshima bombing.
7. 16,000 people died in the disaster. Most of them were anonymous citizens, but well known people who perished were Pliny the Elder (who was organising a rescue party), and Agrippa (a son of the Jewish princess Drusilla and the procurator Antonius Felix) and his wife.
8. Pliny's nephew, Pliny the Younger, survived - he declined to go on the rescue mission and stayed at home in Misenum, across the bay of Naples, writing his letters - although he did evacuate later in the day and helped his elderly and corpulent mother escape.
9. To this day, the type of eruption that happened that day, with clouds of ash rising for miles, is called "Plinian" after Pliny's description. He described the ash cloud coming out of the mountain as resembling a pine tree.
10. Vesuvius is still active - the only active volcano in Europe. It has erupted several times since 79AD, the most recent eruption being in March 1944. None of the subsequent eruptions were anything like as destructive, although in 1631, volcanic ash reached modern day Istanbul over 1,200 kilometres (750 miles) away.