The Royal Society awarded him the Copley Medal in 1770 for his paper, An Account of a Journey to Mount Etna. In 1772 he published his writings on both volcanoes in a volume called Observations on Mount Vesuvius, Mount Etna, and other volcanos. This was followed in 1776 by a collection of his letters on volcanoes, entitled Campi Phlegraei (Flaming fields, the name given by the Ancients to the area around Naples). The volume was illustrated by Pietro Fabris.