Fluidity of lavas.
Forbes, Professor, on the structure of glaciers.
Fragments ejected at Ascension. -at the Galapagos archipelago.
Freshwater Bay.
Fuerteventura (Feurteventura), calcareous beds of.
Galapagos archipelago. -parapets round craters.
Gay Lussac, on the expulsion of carbonic acid gas.
Glaciers, their structure.
Glossiness of texture, origin of.
Gneiss, derived from clay-slate. -with a great embedded fragment.