82 POIiABIZED CONDITION OF THE CHAP. vm. 



effect in these results which caimot be fully accounted 

 for, under the supposition that the current is due 

 entirely to the changes which occur during nutrition ; 

 and I believe that we shall be justified in coining 

 to the following conclusions, and in considering 

 that the so-called muscular and nerve currents may 

 depend upon three circumstances: first, upon the 

 changes which occur during nutrition ; secondly, upon 

 the heterogeneity of the parts, (Including under this 

 term the action of the platinum electrodes, viz. the 

 catalytic action or the combining power of platinum 

 upon the moist animal substances in contact with its 

 surface ;) and, thirdly, upon an electrical state or 

 condition of the muscular or nerve fibre itself. 



In thus considering the muscular or nerve fibre as 

 being in a peculiar state or condition which may be 

 termed polarissed", an objection might be urged to 

 the employment of this term, inasmuch as the term 

 polarity embraces the idea of duality — an antithetical 

 action, which, as we have seen, does not exist in 



■= Dr. Todd, I believe, was the first to describe the true cha- 

 racter of the phenomena I am now speaking of, and to point 

 out their dependence upon nutrition, and also to consider them 

 as being polar in their nature. See the article on the Physiology 

 of the Nervous System in the " Cyclopaedia of Anatomy and 

 Physiology." Du Bois Keymond speaks of the tissue as being 

 in an electro-tonio state. I have avoided using this term electro- 

 tonic, as the facts appear to me to resemble those of a charged 

 Leyden jar, rather than that of a wire conducting a current of 

 electricity. 



