MUSCLE-NERVE PHYSIOLOGY. 535 



lism is no doubt the axis-cylinder. The question whether a nervous 

 impulse is possibly an electrical change, as has been asserted by some, 

 cannot be at present settled, but if it be so, at any rate it differs essenti- 

 ally from an ordinary current, if in no other respect, at any rate in the 

 rate of transmission, 



