18 "Nature's dfctraclcs. 



every-day life; and if so, what he thinks of 

 that little speech he made to the boys fifty 

 years or more ago. 



If we make an analysis of the history of 

 the science of electricity we shall see that it 

 has progressed in successive eras, shortening 

 as they approach our time. For a period of 

 2300 years, from Thales to Franklin, but littl.- 

 or no progress was made beyond the further de- 

 velopment of the phenomena of frictional elec- 

 tricity the most important invention being 

 that of the Leyden jar. From Franklin to Vol- 

 ta was forty-eight years, and from Volta to 

 Faraday about thirty-two years. From this 

 time on the development was very rapid as com- 

 pared with the old days. Soon after Faraday, 

 Morse, Henry, Wheatstone, and others began 

 experiments that have grown, during fifty or 

 sixty years, into a most colossal system of elec- 

 iric telegraphs, telephones, electric lights and 

 electric railroads. In the latter days marvel 

 has succeeded marvel with such rapid strides 

 that the ink is scarcely dry from the descrip- 

 tion of one before another crowds itself upon 

 our attention. Where it will all end no one 

 knows, but that it has ended no one believes. 

 The human mind has become so accustomed to 

 these periodic revelations of the marvelous 

 that it must have the stimulus once in a while 

 or it suffers as the toper does when deprived of 

 his cups. The commercial instinct of the 



