Lectures on Geology: Being Outlines of the Science

Actynolite alluvial alternating ammonites amygdaloidal arenaceous argillaceous argillite augit basalt beautiful beds belemnites bitumen calcareous CALIFORNIA chalk chlorite chlorite schist clay slate coal color columnar compact felspar composed compound conglomerates containing crater crystals deposits distinct earth elevated epidote feet felspar Fibrous foliated formation fossils fracture fragments Geologists Geology gneiss grains granite granular green greenstone grey greywacke gypsum hornblende Humboldt imbedded indurated ingredients iron laminæ laminar lava lignite limestone marble marine marl mass mentioned mica mica slate micaceous schist minerals mountains observed occasionally occur ocean oolite organic remains ostrea passes peat porphyry position primary rocks primitive prismatic pyrites quantity quartz quartz rock Quartz sand sandstone Scaly schist schistose secondary rocks serpentine shale shells sienite siliceous simple sometimes spar species splintery stone strata structure substances surface SYNOPSIS talc tertiary texture theory tion transition trap UNIVERS usually vallies varies varieties vegitable veins volcanic