EPOCH OF DAVY AND FARADAY. 185 



reference to the direction of terrestrial magnetism, 

 might be considered as naturally east and west; 

 and he conceived elements as, in this way, arriving 

 at the doors or outlets at which they finally made 

 their separate appearance. The doors he called elec- 

 trodes, and, separately, the anode and the cathode 1 '; 

 and the elements which thus travel he termed the 

 amon and the cation (or cathion 1 *). By means of 

 this nomenclature he was able to express his 

 general results with ' much more distinctness and 

 facility. 



But this general view of the electrolytical pro- 

 cess required to be pursued further, in order to 

 explain the nature of the action. The identity of 

 electrical and chemical forces, which had been 

 hazarded as a conjecture by Davy, and adopted as 

 the basis of chemistry by Berzelius, could only be 

 established by exact measures and rigorous proofs. 

 Faraday had, in his proof of the identity of voltaic 

 and electric agency, attempted also to devise such a 

 measure as should give him a comparison of their 

 quantity; and in this way he proved that 19 two 

 small wires of platina and zinc, placed near each 

 other, and immersed in dilute acid for three seconds, 

 yield as much electricity as the electrical battery, 



17 Art. 663. 



18 The analogy of the Greek derivation requires cation / but 

 to make the relation to cathode obvious to the English reader^ 

 and to avoid a violation of the habits of English pronunciation, 

 I should prefer cath'ion. 



19 Art. 371. 



