﻿386 M. G. Quincke on the Capillary Phenomena 



Alcohol above ; Olive-oil below. 

 a* =0*7906, <r M =0*9136, 



2« =4*476 mgrms., ct ou =. 0*226 mgrm. 



No. 



2r . 



h . 



hu* 



2rh<r. 



Xou COS OJou 



1. 



2. 



millim. 

 0-363 

 0-330 



millitns. 

 10 

 15 



millims. 

 18-1 

 16-2^ 



mgrms. 

 4-436 

 4-395 



mgrm. 



-0-020 



-0040 



Olive-oil above ; Alcohol below. 

 <r o =0*9136, <r u = 0'7906, 

 2ot = 6*341 mgrms., « OM = 0*226 mgrm. 



1. 



2. 



0582 

 0-346 



10 

 15 



135 

 27-9 



5-77 

 6-19 



-0-28 

 -007 



The observations show that the angle (o ou was not constant in 

 the different experiments, with the exception of the series water 

 above, oil of turpentine below — in which a value u ou is found for 

 Nos. 4 to 7, which very nearly agrees with the determination 

 from observations of drops (Table X. § 10) when the angle <o ou 

 is put =180°. For the measurements 1 to 3 of the same series, 

 the too small value of Xrha- or a ou cos co ou is owing to the very 

 thin layer of water which covers the oil of turpentine. The oil of 

 turpentine at the capillary meniscus of the common surface, freed 

 from the water, being specifically lighter, rose in the column of 

 water, spread itself out (compare § 26), and rendered impure the 

 upper meniscus of the open surface of the water, which no longer 

 possessed the constant for water, but that of a mixture of water 

 and oil of turpentine. In observation No. 1 the water above the 

 oil of turpentine was removed by a piece of blotting-paper. 



In the series of experiments with olive-oil above and water 

 below, the common surface was decidedly concave upward, whilst 

 in contradiction herewith o) ou > 90° would follow from the observed 

 elevations. Hence the cause that too small a value of h u was 

 observed must very likely be sought in the friction of the liquids 

 against the sides of the tube^ which very considerably retarded 

 the condition of equilibrium. 



The same also holds good for the experiments with alcohol and 

 olive-oil given at the end of Table XVIII., where, on account of 

 the smallness of a 0M , the fluctuations are perhaps still more 

 striking. 



22. I have also made a series of experiments with some 

 liquids which mix in all proportions, in which therefore u ou = } 

 and the weight of liquid raised above the common level of the 



