Ml; s \\ .1. SMITH ON THE NATURE OF ELECTROCAPILLARY PHi.NCMKXA. 55 



onlinate, they cross one another a second time. In the neighbourhood of the maxima 

 tin- horizontal distances between the curves are not very accurately determinable ; 

 In it the general nature of the depolarization curve is obvious. 



Fig. 2. 



The vertical dotted line in fig. 1 is drawn as nearly as possible through the highest 

 point of the capillary curve. Immediately to the right of this line there is a dotted 

 curve. The points required to determine this curve were obtained by bisecting the 

 horizontal lines drawn between points on the direct curve corresponding to the same 

 surface tension. Considering any horizontal line, therefore, the intercept made on it 

 between the vertical line and the above dotted curve represents the extent by which 

 a point on the descending branch departs from symmetry with the corresponding 

 point on the ascending branch, with respect to the vertical axis. The whole curve, 

 therefore, represents the manner in which the descending branch of the capillary 

 curve departs from symmetry with the ascending branch, with respect to a vertical 

 axis through the point of maximum surfluv tension. The internal resistance of the 

 electrometer used in the experiment above described was certainly less than 100,000 

 ohms, and probably not much above 50,000 ohms. Hence the depolarization effect 

 upon the form of the curve, due to the internal resistance of the electrometer, lay 

 between 0'5 per cent, and 1 per cent, of the corresponding effect due to the external 

 resistance of 10,000,000 ohms. From an examination of the horizontal distance 

 between the ascending branches of the direct and indirect curves we therefore see 

 that the depolarization effect (due to the internal resistance) upon the ascending 

 branch of the direct curve is negligible within the limits of observation. 



The a.seenilin^ Kraneli of the curve can, therefore, be taken to be sensibly inde- 

 pendent of the depolarization. It is seen from the indirect curve, however, that the 

 depolarization current continues to increase after the maximum is passed, and that, 

 eventually, the rate of increase becomes very rapid. It is also evident from the 

 curves that the rate at which the descending branch of the direct curve departs from 

 symmetry with the ascending branch is very similar to the rate at which the depolariza- 

 tion current increases. The departure from symmetry might, therefore, be very well 

 due to the depolarization. 



