112 



CHAPTER IX. 



TRANSITION TO CHEMICAL SCIENCE. 



THE preceding train^of generalization may justly 

 appear extensive, and of itself well worthy of 

 admiration. Yet we are to consider all that has 

 there been established as only one-half of the science 

 to which it belongs, one limb of the colossal form 

 of Chemistry. We have ascertained, we will sup- 

 pose, the laws of Electric Polarity; but we have 

 then to ask, What is the relation of this Polarity 

 to Chemical Composition? This was the great 

 problem which, constantly present to the minds of 

 electro-chemical inquirers, drew them on, with the 

 promise of some deep and comprehensive insight 

 into the mechanism of nature. Long tasks of re- 

 search, though only subsidiary to this, were cheer- 

 fully undertaken. Thus Faraday 1 describes himself 

 as compelled to set about satisfying himself of the 

 identity of common, animal, and voltaic electricity, 

 as "the decision of a doubtful point which inter- 

 fered with the extension of his views, and destroyed 

 the strictness of reasoning." Having established 

 this identity, he proceeded with his grand under- 

 taking of electro-chemical research. 



The connexion of electrical currents with chemi- 

 cal action, though kept out of sight in the account 

 1 Dec. 1832. Researches, 266. 



