242 Proceedings of Royal Society of Edinburgh. [sess. 
both nerves through the same electrodes C,D, and the density 
would therefore be more nearly equal in the two than with the 
arrangement of fig. 3. As before, a compensator was put in the 
galvanometer circuit. B was not an electrode, but only a movable 
i 
bridge of clay. If we stimulate at I, it will depend upon the 
distance of B from C whether the anodic effect will be positive or 
negative. 
Experiments 6 and 7 are samples of the results got by this 
method. 
Experiment 6 . 
Distances — a, 10 mm.; b, 10 mm.; c, 2 mm.; d, 13 mm. 
Polarising Current. 
Stimulation 
Effect. 
1D| 
-184 
3D| 
- 38 
5D! 
+ 58 
8 D| 
+ 68 
1 D 
+ 138 
1 D Rh. 90 cm. 4 
- 53 
5D! 
+ 30 
8D! 
+ 63 
ID! 
- 79 
2D! 
- 76 
Experiment 7 shows the change of sign on the anodic side even 
with 2 D. The negative effect on the side of the cathode seems 
here to diminish with increase of current, and this might suggest 
that with still stronger currents a positive phase might be found. 
I cannot say that I have found any trace of such an effect, and it is 
only in exceptional cases that the diminution in the negative effect 
appears. 
