348 



TABLE I. The Nerve divided and lifted up at its end. 



Professor Bernard proposes to place another period before the 

 first of these a period corresponding to the normal unexhausted 

 and undisturbed state of nerve, and characterized by contraction at 

 the beginning of the two currents, direct as well as inverse. 



The investigations of Dr. Rousseau show how it is that the order 

 of these contractions is altered by certain changes in the arrange- 

 ment of the nerve acted upon by the current. If the nerve acted 

 upon be divided and lifted up at its end, so as to break the circuit of 

 the derived current*, the order of contraction is that which is put 

 down in the preceding Table ; if the nerve acted upon be raised in a 

 loop (either without dividing it, or, after dividing it, by dropping down 

 the end), so as not to break the circuit of the derived current, the 

 order of contraction is that which is represented in the following 



Table : 



TABLE II. The Nerve in a loop. 



* Figures 3 & 4 on page 354 may serve to illustrate all that need be said 

 respecting the derived current. In figure 3, the sciatic nerve of a frog's leg is 



