LECTURE VIII 



The Fallacy of the Electrodes Water Transport at Anode or Kathode 

 Alteration of Resistance at Anode or Kathode. 



76. Review. This lecture is to be partly retrospective, 

 partly prospective. We shall pass under a rapid review the 

 principal steps of our investigation, inspecting with most care 

 what may appear to us to be weak points, rinding perhaps in 

 those very weak points, points of attraction to further investiga- 

 tion. 



The main principle and "motif" running through the in- 

 vestigation has been that the electrical responses to electrical 

 stimulation are a token and measure of vitality in the objects 

 selected for examination in the retina, in the entire eyeball, in 

 its crystalline lens, in the skin of animals, in the " skin " of 

 plants, in all the living tissues of plants, in living tissues of 

 animals ; and in my last lecture, when I tried to show you how 

 slowly and gradually the vitality of human skin is lost, I 

 ventured to touch upon a fallacy that becomes specially 

 apparent when one undertakes to follow the sign to its last 

 discernible trace. It was lost to sight among accessory 

 physical reactions, fortunately small as compared with the 

 physiological reactions of full vigour, but quite unavoidable, 

 since they are inherent to the apparatus we have to use, I 

 mean the electrodes. And although I call your special atten- 

 tion to the " Fallacy of the Electrodes " at this last stage, I 

 should like to assure you that it has been carefully excluded 

 in all the experiments you have witnessed, and that from the 

 very outset of the investigation the possible simulation of a 

 blaze-current by a polarisation at the electrodes has been con- 

 sidered and excluded. You remember, no doubt, that we hardly 



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