THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



[FIFTH SERIES.] 



MA Y 1887. 



XLV. On the Expansion of Salt- Solutions. By W. W. J. 

 Nicol, M.A.j B.Sc., F.R.S.E., Lecturer on Chemistry, 

 Mason College, Birmingham*. 



[Plates V. & VI.] 



nPHIS is a subject which has at no time attracted much 

 J- attention. With the exception of the experiments of 

 Bischoff, Muncke, Despretz f, and Rosetti J, which deal 

 with special cases, such as the expansion of sea-water, we are 

 indebted to Gerlach § and Kremers || for the whole of our 

 knowledge of the subject ; and this may be summed up as 

 follows : — 



1. The rate of expansion of a salt-solution is the more 

 uniform the more concentrated the solution. Thus, while the 

 line representing the volume of pure water at various tempe- 

 ratures is very pronounced in curvature, the lines correspond- 

 ing to the volumes of various solutions of a salt approximate 

 more and more to a straight line the stronger the solution 

 (Gerlach, loc. cit.). 



2. As a consequence of the above it follows that salt-solu- 

 tions expand faster than water at low temperatures ; but that 

 at high temperatures, on the other hand, the rate of expansion 

 is less than that of water. 



* Communicated by the Author. 



t Fogg- Ann. xli. p. 58. 



% Ann. de Chim. et Phys. (4) xvii. p. 370 (1869). 



§ Spec. Gew. der Salzlosungen. Freiberg, 1859. 



|| Pogg. Ann. vols, c.-cxx. (1857-62). 



Phil. Mag. S. 5. Vol. 23. No. 144. May 1887. 2 D 



