Eyewitness A small planet within a vast Solar System, the Earth is unique in several ways. It has life, it has water, and it has a surface that is continually being renewed.The parts of the Earth that can be seen are just a tiny proportion of the whole planet. Beneath the Earth"s crust lies the thick rocky mantel, and at the centre there is a metal core, which is partly solid and partly liquid. A magnetic field protects the Earth from the Sun"s harmful radiation. Over three-quarters of the Earth"s surface is covered by water. Of all the rain that falls on the land, one-third runs off into rivers and returns to the sea. The rest soaks into the soil where it remains for years as ground water, which keeps rivers flowing in times of drought.Featuring historic scientific apparatus and ground-breaking experiments, Earth is an intriguing look at the world in which we live.- Here is a spectacular, thought-provoking, and highly informative guide to the fascinating story of the Earth. Superb, full-colour photography of geological equipment, rocks, minerals, and 3-D models reveals the ideas and discoveries that have changed our understanding of the world in which we live- See how glaciers create fjords; how beaches are shaped; where Africa is splitting apart along the Rift Valley; ocean-floor volcanoes; the atmosphere from space; the elements in the Earth"s crust; an exploding volcano- Learn how earthquakes are recorded; how the Grand Canyon was formed; about plate tectonics; how rock minerals are changed by weathering; how much of the Earth"s surface is covered by water; where icebergs originate- Discover the age of the Earth; how the ocean floor is mapped; how to sieve fossils from sea floor sediments; how garden snails provided a clue to the continental drift theory; what gases make up the atmosphere; and much, much more