28 ANIMAL ELECTRICITY. — LECTURE I. 



" represent under the figure of the ether vibrations, holding it, 

 " under all conditions, absolutely distinct from electricity. I, 

 " on the contrary, am in favour of a diametrically opposite 

 " view. If I do not greatly deceive myself, I have succeeded 

 " in realising in full actuality (albeit under a slightly different 

 "aspect) the hundred years' dream of physicists and physio- 

 " logists, to wit, the identity of the nervous principle with 

 " electricity." 



Yet du Bois-Reymond was no vitalist ; his animating 

 thought was to analyse the "vital forces" and to find their 

 physical and chemical components. His endeavours con- 

 centrated themselves upon the study of living nerve and 

 muscle, of their electrical manifestations in particular. He 

 laid, perhaps, undue stress upon these manifestations by 

 presenting them as evidence of an identity between the 

 nervous principle and electricity. In his view a filament of 

 nerve was a string of dipolar electromotive molecules, posi- 

 tive at their middle and negative at their two ends; between 

 longitudinal surface and transverse end a current exists 

 (current o{ rest) which undergoes a diminution (negative 

 variation) during excitation of the nerve or of the muscle. 

 In the electrotonic state (Lecture V.) the molecules are re- 

 adjusted with negative poles towards the anode and positive 

 poles towards the kathode. 



Hermann's presentation of matters differs from the above 

 in several particulars. Electrical differences of potential do 

 not pre-exist in normal nerve or muscle, but are the con- 

 sequence of injury and of physiological activity. Injured 

 points are electronegative to normal points. Physiologically 

 active points are electronegative to resting points. Du Bois' 

 negative variation is an action-current. Du Bois' electro- 

 tonic currents are the effect of electrolysis. 



