For the past five centuries, articles about the eruption of Vesuvius have typically said that the eruption began on August 24 of 79 AD. This date came from a 1508 printed version of a letter between Pliny the Younger and the Roman historian Tacitus, written some 25 years after the event. Pliny was a witness to the eruption and provides the only known eyewitness account. Over fourteen centuries of manuscript hand-copying up to the 1508 printing of his letters, the date given in Pliny's original letter may have been corrupted. Manuscript experts believe that the date originally given by Pliny was one of August 24, October 30, November 1, or November 23. This odd scattered set of dates is due to the Romans' convention for describing calendar dates. The large majority of extant medieval manuscript copies - there are no surviving Roman copies - indicate a date corresponding to August 24, and from the discovery of the cities into the 21st century this was accepted by most scholars and by nearly all books written about Pompeii and Herculaneum for the general public.