IIO ANIMAL ELECTRICITY. LECTURE Y. 



to added resistance at the interface, by reason of 

 which a loniritudinal spreading- of current takes place 

 on each side of each electrode. The extrapolar anodic 

 and kathodic currents witnessed at the commence- 

 ment of the lecture are thus accounted for. 



Again you say perhaps "but this is physical, not 

 physiological " ; to which I should reply : " yes cer- 

 tainly it is physical, but that does not mean that it 

 is not physiological." It is physiological in so far 

 as it depends upon physiological conditions, upon the 

 state of nerve that we call living, a state of peculiar 

 physico-chemical lability, subject to all kinds of 

 modifying influences — temperature, moisture, drugs, 

 all the influences in short that we are accustomed 

 to consider in terms of their unanalysed effect on 

 living matter. 



Yes, the phenomena are physical ; but they are 

 also physiological ; the two terms are not mutually 

 exclusive, unless we reserve the term physiological 

 for phenomena of which we are unable to detect 

 the physico-chemical mechanism. The chief aim of 

 physiological study is to express physiological pheno- 

 mena in terms of physics and chemistry. And I 

 venture to hope that we shall be able to push this 

 enterprise a good deal further in this direction ; I 

 shall not be disappointed or surprised if much of our 

 study of living nerve should turn out to be a study 

 of the simple phenomena of electrolytic mobility, and 

 if the depressant action u])on nerve of anaesthetics 



