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Geography-Kozlova (1)

17.7 Mountains that explode 
Since ancient times volcanoes have struck terror and awe into the heart of man: 
but scientists tell us they do more good than harm. Many of the islands in the seas 
and oceans have been thrown up by volcanoes. They have thrown up whole mountain 
ranges too, some of which are very useful because they increase rainfall. The best 
thing of all, however, is the way the lava from volcanoes enriches the soil. This 
explains why farmers crowd the sides of volcanoes, risking death and destruction 
from new eruptions. They can grow such good crops there that they think the risk 
well worth while. 
Some volcanoes are dangerous. Of all the thousands and thousands of them 
scattered about the earth, only about 500 are active. Perhaps not more than 50 
volcanoes are erupting at this moment like Stromboli in the Mediterranean and Izalco 
in El Salvador 
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. Such volcanoes are watched by scientists. Most of the great volcanic 
disasters have been caused by surprise outbursts from volcanoes which have not 
erupted for so long that everyone imagines them to be quite harmless. 
In 1952, one of these, Mount Lamington, in New Guinea 
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, erupted and caused 
six thousand deaths. That disaster was bad but there have been much worse ones. 
Think of Vesuvius which erupted in 79 A.D. burying the towns of Herculaneum and 
Pompeii 
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under its ashes. Have you heard of Krakotoa 
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? Thirty – six thousand lives 
were lost when Krakotoa erupted, and the smoke and dust from the explosion was so 
thick that it was blown right around the world. 
There is so much power in an exploding mountain that man can not attempt to 
control it. But at least he is learning how to save himself from the volcano’s fury. 
Scientists are studying volcanoes ways and learning how to tell in advance when they 
are going to erupt. Thanks to scientists we are not so helpless as people were in 
earlier days, when they were too often caught before they could even try to get away. 


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