] 63 NBEVE FORCE. CHAP. XT. 



obtain any decided evidence of the nerve current 

 being affected during nerve action — I say decided — 

 then we should be called upon to account for its 

 increase or decrease, according to the principles of 

 conservation of force \ and to shew vyhat has become 

 of the force. But if the effects that have been 

 obtained with the galvanometer, viz. a gradital decrease 

 in the nerve current, such as I have observed, be 

 due merely to a disorganization of the nervous tissue, 

 and they are such as are consonant with this sup- 

 position, then nerve force must be ranked as a higher 

 form of force, and the electric condition of the tissue 

 merely a condition for the manifestation of nerve 

 action. To assist in elucidating this question, let 

 us just refer for a moment to the muscular current, 

 and see whether this current is affected during 

 muscular contraction. 



When the electrodes of a galvanometer are so 

 an'anged with the muscular fibre, viz. in contact 

 with the transverse and longitudinal sections, the 

 muscular current is produced ; upon making the 

 muscle contract, the needle returns rapidly to its 

 former position, and passes beyond it. Du Bois 

 Eetmond has designated this effect, " the negative . 

 variation of the muscular current;" the exact mean- 

 ing of the phrase I do not comprehend, if it be 

 intended to express more than the fact. The 

 question, however, is this. Is the return of the 



' On the Conservation of Force. By Prof. Fakadat. " Philo- 

 sophical Magazine," April, 1857. 



