CHAPTER XXX 



ELECTRICITY 



280. Many animals possess the five senses, but only man 

 possesses constructive, creative power, and is able to build on 

 the information gained through the senses. It is the con- 

 structive, creative power which raises man above the level of 

 the beast and enables him to devise and fashion wonderful 

 inventions. Among the most important of his inventions are 

 those which relate to electricity ; inventions such as trolley 

 car, elevator, automobile, electric light, the telephone, the 

 telegraph. Edison, by his superior construc- 

 tive ability, made possible the practical use of 

 the telephone, and Marconi that of wireless 

 telegraphy. To these inventions might be 

 added many others which have increased the 

 efficiency and production of the business 

 world and have decreased the labor and 

 strain of domestic life. 



281. Electricity as first Obtained by Man. 

 Until modern times the only electricity known 

 to us was that of the lightning flash, which 

 man could neither hinder nor make. But 

 in the year 1800, electricity in the form of 

 FIG. 197. -A simple a weak current was obtained by Volta of 



electric cell. J 



Italy in a very simple way ; and even now 

 our various electric batteries and cells are but a modification 

 of that used by Volta and called a voltaic cell. A strip of 



306 



