THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZIiNTE 



AND 



JOURNAL OF SCIENCE. 



[FIFTH SERIES.] 



MAY 1880. 



XLI. On the Diffusion of Liquids. 

 By John H. Long, of Lawrence, Kansas, U. S. A* 



[Plate VII.] 



Historical. 



AMONG- the many subjects of physical inquiry which have 

 claimed the attention of investigators during the past 

 thirty years, one of the most interesting and at the same time 

 not the least important has been that of the diffusion of liquids. 

 Leaving out of consideration the experiments of Jolly |, Lud- 

 wiglf, Cloetta§, and others, who observed the progress of dif- 

 fusion between two media separated by a membrane, and 

 whose results, besides being somewhat contradictory among 

 themselves, have a physiological rather than a physical or 

 chemical interest, we come first, in the consideration of the 

 literature, to the work of Graham ||, which, as has been re- 

 marked, must be regarded as the first and only general inves- 

 tigation of this subject in our possession. 



The method employed by Graham is too well known to 

 require a minute description here. I will simply say that he 

 allowed the diffusion to take place between salt-solutions or 

 other liquids, contained in small phials, and a much larger 



* Communicated by the Author, being a Dissertation presented to the 

 Faculty of Science of the University of Tubingen for the attainment of 

 the degree of Doctor of Science. 



t Zeitschrift fur rationelle Medicin. Also Pogg. Ann. lxxviii. p. 261. 



X Pogg. Ann. lxxviii. p. 307. 



§ Diffusionsversuche durch Membranen mit zwei Salzen. Zurich, 1851. 



|| Phil. Trans. 1850, p. 1. Ann. JPharm. lxxvii. pp. 56 & 129. 



Phil. Mag. S. 5. Vol. 9. No. 57. May 1880. 2 A 



