CHAPTER IX 



HELMHOLTZ IN K.ONIGSBERG ANIMAL ELECTRICITY 



IN after life Helmholtz made important mathe- 

 matical and physical contributions to the theory 

 of electrical actions, and it is interesting to observe, 

 while the fact is in keeping with the plan of his 

 whole career, that he was led into this path from 

 the side of physiology. Before he left Berlin, and 

 while he was in Konigsberg, his friend Du Bois 

 Reymond was carrying on those researches into 

 animal electricity that have made him famous. 

 Helmholtz witnessed and took part in many of his 

 experiments, favoured him with criticisms, and solved 

 theoretical problems that arose in the course of 

 the enquiry, more especially as to the distribution 

 of electricity on conductors of various forms. By 

 using a delicate, high-resistance galvanometer, and 

 by the use of non-polarizable electrodes, a new 

 impulse was given to the experimental investigation 

 of animal electricity. If from living muscle, for 

 example, currents could be led off into the gal- 

 vanometer, as had been done by Nobili about 1827 

 and by Matteucci ten years later, it was manifestly 

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