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. 



