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HOW WE PRODUCE ELECTRICITY 



The influence of the earth's magnetism extends far out 

 into space, and may be one cause of the displays of " north- 

 ern lights" or aurora seen in the sky of the northern and 

 southern hemispheres. You have all heard of "sun 

 spots." While we do not know just what they are, scien- 

 tists find that the activity of sun spots is closely asso- 

 ciated with the magnetic 

 activity on the earth. 



There are many interest- 

 ing facts which we can piece 

 together in telling the story 

 of how electricity has been 

 harnessed and has become 

 the most powerful of man's 

 servants. The Greeks 

 learned of one property of 

 electricity when they 

 rubbed amber, which they 

 called electron, and found 

 that it would pick up small 

 particles. When Franklin 

 sailed his kite in a thunder- 

 storm and discovered that 

 lightning was a form of 

 electricity, another step was 

 taken. r And when Galvani, 

 the Italian scientist, found 

 that the legs of dead frogs 

 twitched when he brought 

 them into a circuit with iron and copper, still another 

 important fact about electricity was discovered. Then 

 came Volta with his discovery that electricity could be 

 generated by chemical means. We might go through a 

 long list of discoveries, each of which gave us more and 

 more knowledge about electricity. 



Franklin took chances with his kite, but 

 he discovered that electricity could be 

 conducted through the wet kite string. 

 What danger did he expose himself to ? 



