222 



(8) 



vast social ameliorations, and vast alterations in the 

 popular conception of the origin, rule, and governance 

 of things. Miracles are wrought by science in the phys- 

 ical world, while philosophy is forsaking its ancient met- 

 aphysical channels, and pursuing those opened or indi- 

 cated by scientific research. This must become more and 

 more the case as philosophic writers become more deeply 

 imbued with the methods of science, better acquainted 

 with the facts which scientific men have won, and with 

 the great theories which they have elaborated. 



If you look at the face of a watch, you see the hour 

 and mirtute-hands, and possibly also a second-hand, 

 moving over the graduated dial. Why do these hands 

 move, and why are their relative motions such as they 

 are observed to be ? These questions cannot be an- 

 swered without opening the watch, mastering its various 

 parts, and ascertaining their relationship to each other. 

 When this is done, we find that the observed motion of 

 the hands follows of necessity from the inner mechanism 

 of the watch when acted upon by the force invested in 

 the spring. 



This motion of the hands may be called a phenome- 

 non of art, but the case is similar with the phenomena 

 of Nature. These also have their inner mechanism, and 

 their store of force to set that mechanism going. The 

 ultimate problem of physical science is to reveal this 

 mechanism, to discern this store, and to show that from 

 the combined action of both, the phenomena of which 

 they constitute the basis must of necessity flow. 



I thought that an attempt to give you even a brief and 

 sketchy illustration of the manner in which scientific 

 thinkers regard this problem would not be uninteresting 

 to you on the present occasion ; more especially as it 



