92 NOMOS. 



this action. According to the premises, indeed, heat 

 could not radiate through the atmosphere, or pene- 

 trate anywhere, without the mediation of chemi- 

 cal changes of one kind or another. Indeed, we 

 Can form no conception of heat apart from these 

 changes. 



In this way, step by step, we have arrived at a 

 point from which we catch a glimpse of a central 

 law. As we come along, the phenomena of electricity 

 are seen to submit themselves to the law of chemical 

 action, and magnetism and light and heat are found 

 to become mere modes of electricity, while 



The whole . . . 



history of at the same time the idea of chemical 

 action has become so comprehensive and 

 general as to lose all proper speciality. In 

 a word > electricity, magnetism, light, heat, 



the law of the an( J chemical action, have all merged into 



laboratory. . 



characters of a common action an action of duality, 

 out of which arise under peculiar circum- 

 stances certain marked movements an action which 

 depends not upon incomprehensible imponderables, 

 but upon certain definite and comprehensible pro- 

 perties of matter. All things have indeed combined 

 to point to a law which is at once simple in its nature 

 and manifold in its operations, and this is the answer 

 we get to the question proposed at the beginning 

 What is electricity ? 



What then ? Is this law the law which dominates 

 in nature ? This is the question which we have now 

 to ask, and which we propose to answer as best we 



