150 NEEVE FORCE. CHAP. XI. 



I should certainly hesitate hefore coming to the 

 conclusion, that no effect is produced upon the 

 nerve current during nerve action; but I certainly 

 have not been able to obtain those definite and 

 constant indications that we have a right to expect, 

 under the supposition that the nerve current, as 

 manifested in the transverse direction of the nerve, 

 is converted during nerve action into a current in 

 the longitudinal direction of the nerve, •which appears 

 to be the opinion of De la Eive, as expressed in the 

 remarks I have already quoted. 



Concluding Eemarks. 

 The conclusions that we have arrived at in the 

 present investigation being of a negative character, 

 may perhaps be considered as any thing but satis- 

 factory. Let us not, however, be led away by the 

 false supposition, that because negative results have 

 only been obtained, that therefore no positive know- 

 ledge is acquired : we may have ascertained a most 

 important fact, if true, and, whether true or not, 

 may partly depend upon our being able to give a 

 satisfactory reason for our failures. Have we not, 

 it may be asked, commenced our inquiry with a 

 false notion in regard to nerve action ; viz. its 

 identity with electric action ? Have we not sup- 

 posed an identity to exist between current force 

 and nerve force, which we have failed to prove? 



tetanic contractions in its own limb, I have not been able to 

 ascertain ; there is no increase in the nerve current. 



