Transcriber's Notes.
Preserved the unusual, but consistent, spelling of "develope."
Preserved the unusual, and inconsistent, references to the Plates. Sometimes Arabic numerals are used, but usually Roman numerals. Most have "a" attached to the name, but not VIII, and sometimes not in the references to them.
Equations were converted to linear text, adding spacing and parentheses as necessary.
Changed "fumarolles" to "fumaroles" on page 3: "fumaroles and salfatares."
Changed "Lyall" to "Lyell" in footnote originally on page 9: "Daubeny, Lyell, Phillips and others."
Changed "throught" to "through" on page 35: "passing through it."
Removed duplicated word "the" on page 40: "the great Calabrian Earthquake."
Page 89 refers to the "Fossa del Vetrano;" elsewhere there are references to "Fossa della Vetrana," which may be what was intended. However, I did not change this.