Document written by Sir Charles Lyell at Messina on the Island of Sicily describing his visit there in the autumn of 1857. The bulk of the document is spent describing the way lava flows down both steep and gentle slopes and specifically discusses the lava flow resulting from the 9 month long eruption of 1852/3. In addition he discusses the formation of the Val del Bove, 9 November 1857.

Letter to Leonard Horner from Sir Charles Lyell discusing the internal structure of lava flows. Lyell also remarks on the probable nature of the additions to the core of Mount Vesuvius that had occurred that year, with illustrations, 10 December 1857.