Note 22 — Chapter IV
Reading edition
See Desmarest's classic map and his papers in Mem. Acad. Roy. Sciences, Paris, 1774, 1779; Journ. de Physique, 1779; Scrope's Geology of Central France, 1827, and Extinct Volcanoes of Central France, 1858; Lecoq's Époques Géologiques de l'Auvergne, 1867; M. Michel Lévy, Bull. Soc. Géol. France, 1890, p. 688; M. Boule, Bull. Carte Géol. France, No. 28, tome iv. 1892.