LAW; — ITS DEFINITIONS. 109 



ultimate agency to which the machinery is due, 

 whereas in the machinery of Nature the ultimate 

 agency is concealed from sight. But it is the 

 very business and work of Science to rise from the 

 Visible to the Invisible — from what we observe 

 by Sense to what we know by Reason. 



And this brings us to the Fifth meaning in which 

 the word Law is habitually used in Science, — a 

 meaning which is indeed well deserving of attention. 

 In this sense, Law is used to designate, not any 

 observed Order of facts, — not any Force to which 

 such Order may be due, — neither yet any com- 

 binations of Force adjusted to the discharge of func- 

 tion, but — some purely Abstract Idea, which carries 

 up to a higher point our conception of what the phe- 

 nomena are and of what they do. There may be 

 no phenomena actually corresponding to such Idea, 

 and yet a clear conception of it may be essential 

 to a right understanding of all the phenomena 

 around us. A good example of Law in this sense 

 is to be found in the law which, in the Science of 

 Mechanics, is called the First Law of Motion. 

 The law is, that all motion is in itself, (that is to 

 say, except as affected by extraneous Forces,) uni- 



