MESSRS. A. WALLER AND A. DE WATTBVILLE OK THE INFLUENCE 
that of the latter, being more vascular and susceptible, therefore of greater increase of 
vascularity under the influence of the current. 
We made the conditions of experiment unfavourable to the results anticipated by 
using a weaker current than the original current when it was desired to prove 
augmentation of excitability, a stronger current than the original current when it was 
desired to prove diminution of excitability. This was done for the galvanic test by 
altering the number of cells so that the galvanometer deflection was evidently smaller 
or greater than before. The instruments at our disposal did not allow us to apply 
this d fortiori device to all the cases of the question, but we established our prin¬ 
cipal results by its means, and we think that the proof of these may be taken to cover 
the remaining cases of which the results are congruent. 
Tracing B, with the accompanying description, are given as formal examples of the 
application of this proof as regards the polar region. Tracings C and D illustrate a 
simpler and more direct proof of the physiological nature of the after-kathodic change. 
Ti’acing B. 
Tracing B. 11,000 oliras additional resistance in circuit. 
Cells. 
a. 
K.C.C. 
b. 
K.T). 
.120 
0. 
K.C.C. 
.126 
d. 
K.D. 
.120 
e, 
K.O.C. 
.126 
f- 
Interval. 
9- 
K.C.C. 
.120 
h. 
K.C.C. 
.116 
The contractions at (e) with stronger current are smaller than those at (a); therefore the excitability 
is diminished. The contractions at (Ji) with weaker current are greater than those at (a) ; therefore the 
excitability is increased. 
