Pliny the Younger's Letters About the Eruption of Vesuvius(pompeii.org.uk)

https://www.pompeii.org.uk/s.php/tour-the-two-letters-written-by-pliny-the-elder-about-the-eruption-of-vesuvius-in-79-a-d-history-of-pompeii-en-238-s.htm