Il6 ANIMAL ELECTRICITY. LECTURE V. 



and with various electrolytes I might have shown 

 deflection, now in the direction of the make, now in 

 the direction of the break. But now I answer that 

 it is physiological, and shall illustrate this statement 

 by killing the nerve (dipping it into hot water and 

 replacing it on the electrodes), and showing that on 

 the dead nerve there is no longer any deflection in 

 the direction of the break when the nerve is traversed 

 by the same series of alternating currents. As you 

 see, the galvanometer spot remains unmoved, even 

 when I considerably strengthen the induced currents ; 

 it is not till these are raised to an excessive strength 

 that the spot begins to shift. This is a physical 

 effect which I do not understand, and shall there- 

 fore make no attempt to explain. It is however 

 easy to distinguish from the deflection afforded by 

 living nerve. 



Well then, admitted that the deflection in the 

 direction of the break is "physiological," present with 

 the living nerve but absent from the dead nerve, and 

 dependent upon the polarisability of living nerve — 

 are we able to proceed further in our explanatory 

 analysis ? 



Not much further, with any legitimate assurance; 

 v. Fleischl gives a highly complex explanation which 

 I shall not reproduce to you.^ Hermann regards it 



^ V. Fleischl's experiment and his interpretation of it are 

 given in the "Wiener Sitzungsberichte, 1878. 



