CHAPTER XVI. 



HOW THE TELEPHONE TALKS. 



Everybody knows what the telephone is be- 

 cause it is in almost every man's house. But 

 while everybody knows what it is, there are 

 very few (comparatively speaking) that know 

 how it works. If you remember what has been 

 said about sound and electromagnetism it will 

 not be hard to understand. 



When any one utters a spoken word the air 

 is thrown into shivers or vibrations of a pecu- 

 liar form, and every different sound has a 

 different form. Therefore, every articulate 

 word differs from every other word, not only 

 as a shape in the air, but as a sensation in the 

 brain, where the air-vibrations have been con- 

 ducted through the organ of hearing; other- 

 wise we could not distinguish between one 

 word and another. Every different word pro- 

 duces a different sensation because there is a 

 physical difference, as a shape or motion, in 

 the air where it is uttered. If one word con- 

 1" ( >0 simultaneous air-motions and an- 

 other 1 ."><)() you can see that there is a physical 

 or mechanical difference in tin- air. 

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