194 UNIVERSAL DIFFUSION 



appeared a very imbecile, and the cui bono generation 

 would have laughed at his silly labours. But when he- 

 announced to his school that this amber held a soul or 

 essence, which was awakened by friction, and went forth 

 from the body in which it previously lay dormant, and 

 brought back the small particles floating around it, he 

 gave to the world the first hint of a great truth which has 

 advanced our knowledge of physical phenomena in a mar- 

 vellous manner, and ministered to the refinements and to 

 the necessities of civilisation. Each phenomenon which 

 presents itself to us, however simple it may appear to be,, 

 is an outward expression of some internal truth, the inter- 

 pretation of which is only to be arrived at by assiduous 

 study, but which, once discovered, directs the way to new 

 knowledge, and gives to man a great increase of power. 

 There is no truth so abstract that it will not find its useful 

 application, and every example of the ministration of 

 Physical Science to the purposes of humanity is an evi- 

 dence of the value of abstract study, and a reply to the 

 utilitarian in his own language. 



Electricity appears to be diffused through all nature ; 

 and it is, beyond all doubt, one of the most important 

 of the physical forces, in the great phenomena of crea- 

 tion. In the thunder-cloud, swelling with destruction, 

 it resides, ready to launch its darts and shake the earth 

 with its explosions: in the aerial undulations, silent 

 and unseen, it passes, giving the necessary excitement 

 to the organisms around which it floats. The rain- 

 drop the earth-girdling ocean and the ringing waters 

 of the hill-bom river, hold locked this mighty force. 

 The solid rocks the tenacious clays which rest upon 

 them the superficial soils and the incoherent sands, 

 give us evidence of the presence of this agency ; and in 

 the organic world, whether animal or vegetable, the ex- 

 citement of electrical force is always to be detected. 



In the solar radiations we have perhaps the prime mover 

 of this power. In our atmosphere, when calm and cloud- 



