THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



[FIFTH SERIES.] 



MA Y 1878. 



XL VI. On the Edge-angle and Spread of Liquids on Solid 

 Bodies. By G. Quincke*. 



[Plate XII.] 



1. JNTRODUCTION.—In a former communication f I 

 have investigated the phenomena of capillary action 

 at the common surface of two fluids, and have measured the 

 capillary constant, or tension, a 12 , of this common surface^ by 

 various methods. 



The fluid particles themselves must be assumed to have a 

 ready mobility, in order that the condition of equilibrium may 

 be rapidly attained. This is, of course, only approximately 

 the case. The more viscous the fluids considered, and the 

 greater the friction of the fluid particles, either of the same 

 fluid or of the different fluids, against one another, the more 

 slowly will the condition of equilibrium be attained. The 

 course of the phenomena may be essentially modified from 

 this cause. 



* Translated by Silvanus P. Thompson, from PoggendorfPs Annalen. 



t Pogg. Ann. cxxxix. pp. 1-89 (1870) ; and Phil. Mag. [IV.] vol. xli. 

 No. 273 (April 1871). 



\ [The subjoined extract from the memoir of 1871 referred to above 

 explains the author's use of symbols. — Transl.] : — "In the following 

 memoir I shall use the same notation as in my former communications on 

 Capillary Phenomena (Pogg Ann. 1858-69), and shall distinguish the 

 magnitudes which relate to a point P ] or P 2 of the free surface of the 

 liquid 1 or 2 by means of the suffix 1 or 2, the magnitudes which relate 

 to a point P x 2 of the common surface of two liquids 1 and 2 by means of 

 the double suffix 1 2." 



Phil. Mag. S. 5. Vol. 5. No. 32. May 1878. Y 



