I've just come across some more interesting digital books on Vesuvius, this time "Campi Phlegraei, Observations on the Volcanoes of the Two Sicilies". The following description is taken from the Claremont Libraries Digital Collections website:
Campi Phlegraei is a firsthand report which documents the late eighteenth century eruptions of Mount Vesuvius. Written by Sir William Hamilton, the British envoy to the Neapolitan royal court in 1764, the work is named for the area around Naples known locally as the Campi Phlegraei or "flaming fields." This name refers to the frequent and violent eruptions of Mount Vesuvius. The area was a popular destination for wealthy travelers undertaking the Grand Tour because of the long history of volcanic activity as well as the classical sites, Pompeii and Herculaneum, which were excavated in 1748 and 1738 respectively.
Hamilton was able to observe the volcano from his arrival in Naples on November 17, 1764, through the eruptions which lasted until October 20, 1767. He became a Fellow of the Royal Society and wrote a series of letters describing the activity of the volcano. The letters were to be read aloud at the Society's meeting and published in its Transactions. The letters make up the text of the Campi Phlegraei. Hamilton engaged the Anglo-Neapolitan artist Peter Fabris to create sketches in situ to illustrate the work. The sketches were reproduced in prints that were hand colored individually by local artists.
Hamilton applied focused attention resulting in a work which is important to the science of volcanology due to the precise descriptions of the changes in the appearance of the volcano, the lava flows and other volcanic activity. The illustrations document the Naples area of the 1700s, aspects of life in Italy of the era, and most importantly, the geological conditions of Mt. Vesuvius and the surrounding terrain.
Volume one of the Campi Phlegraei is predominately text with a single plate and a map. Volume two is predominantly plates with textual descriptions. The third book is a supplement to the original two volume work. The supplement was published in 1779 and describes the eruption of Mt. Vesuvius in August 1779. The supplement is composed of letters written to The Royal Society of London and five hand-colored plates illustrating the volcanic activity.