BOOK III. 



CHAPTER I. 



Electricity. 



" Nature will not deliver her oracles to the crowd, nor by 

 sound of trumpet. We must open our minds to her in solitude, 

 with the simplicity of children, and look earnestly in her face for 

 a reply." WALTER SAVAGE LANDOR. 



THE grand requisite to a right understanding of 

 nature, is to watch attentively all the changes 

 that mark her progress, and the various circum- 

 stances by which they are attended. Perhaps 

 there is not a more striking characteristic of the 

 present age, than the vast amount of industry 

 and talent that are devoted to the cultivation 

 of separate branches of science, which cannot be 

 understood but as connected parts of one har- 

 monious system. The leading object of all 

 science is to reduce a multitude of phenomena 

 to some universal principle, or general law, which 

 pervades the entire constitution of matter. But 

 how is it possible to arrive at universal facts or 

 fundamental laws, without regarding nature as a 

 whole ? 



