Sidney Lee, Dictionary of National Biography: Index and Epitome alphabetic letter H, entry 13358 diplomatist and archæologist; grandson of William Douglas, third duke of Hamilton [q. v.]; M.P., Midhurst, 1761-4; plenipotentiary at Naples, 1764-1800; K.B., 1772; made twenty-two ascents of Vesuvius, witnessing 1776 and 1777 eruptions; visited Etna; F.R.S., 1766; published ‘Campi Phlegræi,’ 1776 (also a supplement, 1779), and other works describing observations of volcanoes and Calabrian earthquakes; sent account of Pompeian discoveries to Society of Antiquaries; sold collections of Greek vases and antiquities to British Museum, 1772; and to Thomas Hope, 1801; purchased from Gavin Hamilton (1730-1797) [q. v.] ‘Warwick Vase,’ and from Byres, the architect, ‘Portland Vase’; privy councillor, 1791; married Emma Hart [see HAMILTON, EMMA], 1791; entertained Nelson at Naples, 1798; accompanied Neapolitan court to Palermo, 1798; travelled to England with Nelson; D.C.L. Oxford, 1802. [xxiv. (6.53)
Charles Dickens, Little Dorrit page 208 But for that resolution so often recalled, Clennam might have wished him in the crater of Mount Etna, in return for this civility. (6.04)
Three years in California. By Walter Colton page 288 It is possible that these blow-holes, as they are called, were the vents of volcanoes, performing the same functions as those found beneath the shaking cone of Etna. (7.06)