Earthquakes and volcanoes frighten people but they also give them great pleasure. Although volcanoes are mostly beautiful mountains, they have destroyed cities, forests and farmland throughout history. The word volcano comes from the name of the island of Vulcano, just 5 north of Sicily. In classical times, people thought k was the home of Vulcan - the god of destruction. Science has improved greatly. However, we still know very little about volcanoes. A volcano is a kind of chimney, or vent. This chimney goes down to a liquid deep in the earth, called 'magma'. Three types of material come out of this vent: a hot liquid ('lava'), pieces of rock and great quantities of gas. The lava and rock often collect around the vent and form the volcano's 'cone'.
Scientists often classify, i.e. group, volcanoes according to the type of vent and kind of explosion.
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