478 ELECTRICITY. 



take place in experiment. Universally, whenever an 

 electric body is brought near others in their natural 

 state, it produces contrary electricity in those parts which 

 are nearest to the electrified body. This is called induc- 

 tion of electricity. 



These may be considered as the fundamental princi- 

 ples of the theory. It was originally proposed by Du 

 Faye, a French philosopher. Franklin proposed another, 

 in which he supposed onlv one kind of electricity. When 

 bodies had an excess of this, they were said to be posi- 

 tively electrified ; when there was a deficiency, ne- 

 gatively. The positive electricity of Franklin corres- 

 ponds to the vitreous of Du Faye, and the negative to the 

 resinous. The theory of two fluids is now almost uni- 

 versally received. We shall accordingly adopt its 

 phraseology in this treatise, and proceed to describe the 

 facts which constitutes this science, under the following 

 heads. 



I. Effects produced by electricity in its natural state. 



II. Means of accumulating the electrical poic cr. 



III. Effects produced by electricity when accumulated. 



IV. Effects produced by electricity when in motion. 



I. .EFFECTS PRODUCED BY ELECTRICITY IN ITS NATURAL 

 STATE. 



We know, unfortunately, very little in regard to this 

 branch of our subject. The univetsal diffusion of this 

 agent, leads us to suppose that the Author of Nature, 

 who does nothing in vain, accomplishes some important 

 ends by it, in its ordinary and natural operation. What- 

 ever these ends may be, philosophers have almost en- 

 tirely failed to discover them. Various experiments have 

 been performed with a view to develope some unseen 

 power exerted by electricity, in the process of vegetation, 

 in muscular motion, in the phenomena of crys- 

 tallization, and in the ordinary fluctuations of wind 

 and weather. But these attempts have been attended 

 with very partial success. Some things, indeed, of a 

 very interesting character have been brought to light, 

 and which, in a more full treatise than this, would de- 



