1876.] 



Excitability of Motor Nerves. 



11 



probably become more than proportionally increased to the more sudden 

 stimulus. In order to test the correctness of this hypothesis, Dr. 

 Sanderson further suggested that the period of the muscle's latent stimu- 

 lation before and after cutting should be taken, and also that the follow- 

 ing experiment should be tried. By means of an appropriate apparatus, 



1. 2. 3. 4. 



Descending Ascending Descending Ascending 



make. make. break. break. 



the uncut muscle was to have supphed to it a galTanic stimulus of mea- 

 sured duration ; and this duration was to be graduated down to the point at 

 which the break succeeded the make with a rapidity just sufficiently great 

 to prevent the muscle from responding to either stimulus. The strength 

 of the current remaining unaltered, the nerve was then to be cut through 

 at the usual place ; and, lastly, it was to be observed whether or not the 

 muscle was thus rendered more sensitive to stimuli of short duration. So 

 far as this part of the inquiry has as yet proceeded, the results are as follow. 

 Section of the nerve (either just above the knee or immediately after 



