A First Book in Geology: Designed for the Use of Beginners |
Other editions - View all
Common terms and phrases
animals animals and plants basins become beds beneath bits body bottom buried called carbon Carboniferous carried caverns caves changes claystones coal cold comes constantly contain coral coral reefs creatures crevices crystalline crystals currents decay deposits dissolved earth earth's history earth's surface earthquake easily fall feet feldspar fishes flows foraminifera force forests fossils give glaciers gneiss grains grow heat higher hornblende hundred insects lakes land lava LESSON lime limestone living lower mammals mass matter melted metals mica miles mineral mollusks motion mountains move ocean pebbles poles protozoa quartz radiates rain reefs regions reptiles river rocks sand sandstones sea-floor sea-shore sea-water shape shells shocks shore side Silurian sink holes slowly soil solid sometimes species stones stream structure substances things thousand Triassic tropics valleys veins vertebrates volcanoes waves wear winds
Popular passages
Page 29 - Soils are the wreckage of the rocks, as they wear down under the action of the air, the rain and frost, the roots of plants and the stomachs of worms. This wearing has been going on for a very long time in the past, so that the soil now on any country may have gradually settled downwards for thousands of feet, as the rocks slowly rotted away and were carried off by the streams.