The island of Ischia, off the coast of Sicily, c 1770.
© Science Museum / Science & Society Picture Library
Hand-coloured etching by Peter Fabris (active 1768-1779). Illustrated plate from William Hamilton's study of Italian volcanoes, 'Campi Phlegraei' (published Naples, 1776). Shows (1) a mountain of volcanic origin, (2) the town of Ischia, (3) the castle of Ischia and (4) a strata of erupted volcanic matter. The island is rich in mineral waters of differing degrees of heat. Based on letters to the Royal Society, Hamilton's book is a seminal work on the nature and effects of volcanic explosions.