FARADAY. 411 



If his discovery of Magneto-electricity may be ranked 

 with that of the pile by Volta, this new discovery 

 may almost stand beside that of Definite Combining 

 Proportions in Chemistry. He passed on to Static 

 Electricity its Conduction, Induction, and Mode of 

 Propagation. He discovered and illustrated the prin- 

 ciple of Inductive Capacity; and, turning to theory, 

 he asked himself how electrical attractions and repul- 

 sions are transmitted. Are they, like gravity, actions 

 at a distance, or do they require a medium? If the 

 former, then, like gravity, they will act in straight 

 lines; if the latter, then, like sound or light, they may 

 turn a corner. Faraday held and his views are gain- 

 ing ground that his experiments proved the fact of 

 curvilinear propagation, and hence the operation of a 

 medium. Others denied this; but none can deny the 

 profound and philosophic character of his leading 

 thought.* The first volume of the Researches contains 

 all the papers here referred to. 



Faraday had heard it stated that henceforth phys- 

 ical discoveries would be made solely by the aid of 

 mathematics; that we had our data, and needed only 

 to work deductively. Statements of a similar character 

 crop out from time to time in our day. They arise 

 from an imperfect acquaintance with the nature, pres- 

 ent condition, and prospective vastness of the field 

 of physical enquiry. The tendency of natural science 

 doubtless is to bring all physical phenomena under the 

 dominion of mechanical laws; to give them, in other 

 words, mathematical expression. But our approach to 

 this result is asymptotic; and for ages to come pos- 

 sibly for all the ages of the human race Nature will 



* In a very remarkable paper published in PoggendorfFs ' An- 

 nalen ' for 1857, Werner Siemens accepts and develops Faraday's 

 theory of Molecular Induction. 



