90 



ANIMAL ELECTRICITY. LECTURE IV. 



In illustration of the first of these two points I 

 cannot do better than show you an extremely simple 

 experiment that suggested itself only two or three 

 days ago as a possible lecture demonstration, and 

 of which nevertheless I already venture to say that 

 it does not fail. I only wonder how it is that I 

 never tried it before, for I have frequently wanted 

 an illustration of the kind, and wondered whether 

 the living tissues of the human body traversed by a 



Current 

 > 



Counter' Current 

 < 



Fig. 38. — Plan of apparatus for the demonstration of " internal polarisation 

 of the human subject. 



galvanic current give rise to any demonstrable internal 

 polarisation, or whether they are so to speak kept 

 too well washed by the alkaline blood traversing their 

 capillaries. 



Experiment, — Here are two vessels of salt solution 

 R and L connected with the two poles of a battery. 

 Here are two other vessels R' and L' of salt solution 

 connected with a galvanometer, which is shunted to 

 such an extent that on completing circuit through my 



