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LIVING IN AN OCEAN OF AIR 



many could tell how the air was used. It might be easier 

 to answer the statement that air helps us fly our kites, 

 sail our boats, hold up toy balloons, and turn toy wind- 

 mills. Practical boys will at once think of air in bicycle 



What holds a kite up ? How do you get a kite up in the air ? Why does the boy 

 run with his kite? 



and auto tires, while a girl might think of a cool breeze 

 produced by means of an electric fan. Perhaps someone 

 knows how the air helps fill a fountain pen or a medicine 

 dropper or at least how it helps you to drink soda water 

 through a straw. Let us look into some of these uses of 

 the air and see if we can explain them scientifically. 



What Is a Vacuum? Air not only fills what we call 

 "empty" bottles, but it fills our houses and all outdoor 

 space. The Greeks had a saying, "Nature abhors a 

 vacuum," which was handed down from generation to 

 generation. They knew, as we know, that it is difficult 

 to keep air out of any space. If air is pumped out of a 

 jar so that there is nothing in it, we say a vacuum is 



