106 PROCEEDINGS OF THE ACADEMY OF [1888. 



EESEARCHES UPON THE GENERAL PHYSIOLOGY OF NERVE 



AND MUSCLE. 



BY Dr. HENRY C. CHAPMAN AND Dr. ALBERT. P. BRUBAKER. 



No. 1. 



Electrical currents and Electro-motive force of Muscle and Nerve in 

 frog. Whatever view may be entertained as to the nature of the 

 electrical currents present in injured muscle or nerve, whether the 

 same be regarded as pre-existing in the uninjured condition, or as 

 being developed through injury, there can be no difference of opinion 

 as to the fact that such currents exist, at least in the injured condi- 

 tion. In as much,, however, as so far known to the authors of this 

 communication, all researches hitherto undertaken with the object 

 of demonstrating the presence of electrical currents in muscle and 

 nerve, and of more particularly determining the electi-o-motive force 

 of the same, have been made by Prof. Du Bois Reymond it does 

 not appear superfluous to bring before the attention of the Academy 

 the results of some recent investigations made by the authors in the 

 Laboratory of Jefferson Medical College upon large specimens of our 

 our common frog, Rana. Cateshiana. That the presence of electri- 

 cal currents in nerve and muscle should have long escaped the notice 

 of physiologists was doubtless due, not only to the imperfect forms of 

 galvanometers formerly in use, but also to the fact of electrical cur- 

 rents being developed whenever two electrodes were placed in contact 

 with organic tissues. With the construction of delicate galvanom- 

 ters, like those of Wiedemann, and of non-polarizable electrodes, that 

 is of electrodes that will convey or divert an electrical current present 

 in a muscle or nerve to a galvanometer, without generating one, it 

 became possible to demonstrate without cavil that injured muscle and 

 nerve are seats of electro-motive force. The instruments made use of 

 in obtaining the results tabulated below, were of the convenient form 

 devised for this purpose by Prof Du Bois Reymond,^ to whom this 

 branch of science is so much indebted, and consisted of a Wiedemann 

 galvanometer with telescope and scale, around compensator, mercurial 

 keys and whippe and non-polarizable diverting cylinders and divert- 

 ing vessels ^ the latter or non-polarizable electrodes being always 



1 Gesammelte Abhandlungen, Leipzig, 1875, Band I. 



2 A description of these instruments will be found in Chapman's Physiology 

 1887, Chap. XXXVIII. 



