50 ANIMAL ELECTRICITY. LECTURE IL 



muscle works and does not diminish, carbon and oxy- 

 gen must come to it, as carbon with oxygen leave it. 

 There must be integration reparative of disintegra- 

 tion. And although no doubt during heightened 

 action the disintegrative movement is hastened, and 

 during subsequent repose reintegration, yet we must 

 not too absolutely imagine as independent and disso- 

 ciated these two opposite movements — they are rather 

 the concomitant aspects of one complex process of 

 metabolism, although, no doubt, action gives promi- 

 nence to the negative movement of expenditure, and 

 rest favours the positive movement of recuperation. 



Turninor back to the electrical sigfns of nerve 

 action, we find this opposition of movements mirrored 

 as it were by the currents during and after action. 

 During action we have a negative effect, after action 

 we have a positive after-effect. To which double 

 statement I may add that in certain states of nerve 

 we may witness even during action a positive effect 

 that may possibly signify that even during action 

 integration may predominate over disintegration. 

 But however that may be, we shall find in the 

 empirical study of reagents that this positive varia- 

 tion contributes some very significant items to the 

 series of arguments upon which we are about to 

 enter. 



To sum up, we shall have as elements of study 

 three principal effects upon a nerve set up for experi- 

 ment as shewn in ^^. lo. 



