On the Excavation of Valleys as Illustrated by the Volcanic Rocks of Central France

Allier alluvial beds alluvion alluvium ancient alluvion ancient basalt angle Ardêche Auvergne barrier basaltic plateau beds of rounded boulders Cantal Central France Chaluzet cheire cliff columnar basalt Combres Côme compact basalt course Couze crater dammed depth descends described district Edin epoch eruptions Etang de Fung excavation extinct quadrupeds Farm of Boulade feet in thickness feet thick filled flowed Fontaulier fossil bones fragments geologists Geology of Central gorge granite gravel height hill Hyæna Issoire lacustrine deposites lake lava current lava-current marls miles modern Mont Dor Mont Perrier Monton Montpezat Pardines pebble-bed phenomena phonolite pitchstone Plate Pontgibaud Pranal present river primary rock prisms of basalt pumice quadrupeds quartz right bank rounded pebbles sand Scoriaceous Lava scoriæ Scrope seen side Sioule slope St Maurice stream subjacent gneiss surface Tartaret tertiary marls tertiary strata Thueyts trachytic breccia trachytic conglomerates transported matter Unconformably Vayres Velay vertical Vivarais volcanic matter waste