Geology, a Manual for Students in Advanced Classes and for General Readers

abundant action Ammonites angles animals aqueous rocks basalt beds brachiopods calcareous called Cambrian carbonate of lime carbonic acid Carboniferous cement chalk character chemical clay cliffs coal measures coast colour conglomerate consists contain coral Cretaceous crust crystalline crystals denudation deposits derived Describe Devonian earth embedded England evidence extinct felspar flint formed fossils fresh-water genera geological glacial glacier gneiss gradually granite Greensand grit hard heat hills igneous rocks iron Isles known lakes land lava layers Lias limestone London clay lower marine marls mass material matter metamorphism mica millstone grit mineral Miocene North numerous occur Oolite origin oxide Paleozoic period Permian plants Pliocene portion present pyrites quartz regions remains reptiles river salt sand sandstones saturation schists shales shells silicate Silurian slates slope soil species stone strata stratified rocks surface Tertiary thin trilobites unconformably upper valley various vegetable volcanic Yorkshire