52 STUDIES IN ELECTRO-PHYSIOLOGY: 



sympathetic ; in motor, sensory, and mixed nerves ; in a 

 minute section, as well as in a large mass, of nervous sub- 

 stances ; in a small fibril as well as in a large muscle ; in 

 the skin, spleen, testicles, kidneys, liver, lungs, and 

 tendons ; but not in fasciae, sheaths of nerves, and sinews. 



It is over one hundred years since Du Bois-Reymond 

 taught us this, and we have learned nothing from it. 



The next prominent exponent of electro-physiology 

 was Dr. C. B. Radcliffe, who sought to prove that the 

 sheaths of fibres of nerve and muscle during rest are 

 charged with electricity like Leyden jars. He postulated 

 the theory that the sheaths of the fibres were dielectric, 

 but did not attempt to differentiate the" open " from the 

 " closed " circuits of the nervous system. 



He said: "When a' nerve or muscle passes from 

 action to rest it resumes its condition of charge." But 

 " elongation, therefore, is the result of charge, and con- 

 traction of discharge." 



This view is, of course, quite fallacious. The reverse 

 obtains. When an impulse is conveyed to certain groups 

 of sarcomeres they contract ; when discharge takes place 

 they elongate, and are again in readiness for charge. 



Then we had Professor John Trowbridge, of Harvard 

 College, who cast grave doubts upon the interesting and 

 hitherto accepted conclusions of Du Bois-Reymond in 

 regard to animal electricity, and ascribed the whole 

 phenomena as due to the alleged fact that two liquids of 

 dissimilar chemical character, separated by a porous 

 partition, gave rise to a current of electricity. More 

 recently this somewhat far-fetched hypothesis of dissimilar 

 fluids has been substituted by two dissimilar metals ; i.e., 

 electrodes ; the theory being that electrical action is set 

 up between two electrically dissimilar metals the elec- 

 trodes in the presence of an exciting liquid, such as the 

 secretion of the sweat-glands. 



