64 



Mi; s \v. .1 SMITH ON THE NATURE OF ELECTROCAPILLARY PHENOMENA. 



independent of the accuracy of the division of the scale. The zero of this scale ftl 

 about 12-4 centims. above the capillary point, so that the reading correspond,.,- to 

 the maximum surface tension, in dilute sulphuric acid, was about 31'6 centims. 

 position of the summit of the mercury column relative to the scale could be deter- 



mined to within about a tenth of a millimetre. It would not be difficult to arrange 

 for a greater degree of accuracy in this measurement ; but, apart from the increase 

 in the time occupied by the observations, which more delicate determination would 

 involve, the above error does not exceed that introduced from other causes. Usually 

 the solution to be examined was placed in a Clark cell tube of the Rayleigh H form. 



