On 5 February AD 62, an earthquake of an estimated magnitude of between 5 and 6 and a maximum intensity of IX or X on the Mercalli scale struck the towns of Pompeii and Herculaneum, severely damaging them. The earthquake may have been a precursor to the eruption of Mount Vesuvius in AD 79, which destroyed the same two towns. The contemporary philosopher and dramatist Seneca the Younger wrote an account of the earthquake in the sixth book of his Naturales quaestiones, entitled De Terrae Motu.