452 



MESSRS. F. GOTCH AND V. HORSLEY 



air by the ligature. A separate pair of non-polarisable electrodes was placed in 

 connection with the cross section and the surface respectively of each nerve. A 

 piece of cord 1 centim. long was now removed from the upper end of the lower 

 fragment of the cord, thus exposing a fresh cross section of all the columns. 



The left sciatic nerve showed a resting electrical difference between the surface and 

 cross section, which was balanced by a difference of 01 Daniell ; the right nerve 

 showed a rather less marked difference balanced by 008 Daniell. 



Each pair of nerve contacts was alternately connected with the galvanometer, a 

 Pohl s reverser without cross wires being used to switch either set of contacts into 

 connection. The following deflections, opposed in direction to the resting difference, 

 were obtained from the nerve when the cut ends of the various columns designated 

 below were excited for 5 seconds : 



LEFT Nerve connected. 



KIGHT Nerve connected. 



The intensity of the stimulus was now doubled. 



LEFT Nerve connected. 



Strength of stimulus. 



Region excited. 



ISccoiularv coil. 



1000 



Left posterior column . . . 



Left lateral . . . 



Right posterior . 



Right lateral . . . 



Effect. 



190 



5 



30 



Nil. 



