

Conductivity and Fluidity of Solutions. = 481 
In solution 1, the ionization remains constant at all 
temperatures, but for the other solutions there is a very 
marked decrease with rise of temperature, and this becomes 
greater the stronger the solution. 
Referring back to Table HK, it will be seen that for solution 1 
there has been no change in ‘fluidity by the addition of the 
salt to the water. It is only when the fluidity becomes 
smaller by the addition of the salt that there is the diminishing 
of the ratio . with rise of temperature, so that the 
diminution of 5 may be due to two causes, the re-combi- 
nation of the ions and the retarding influence of the molar 
viscosity; and the latter influence may be felt in much weaker 
solutions than one has generally supposed. 
I have at the begininng of this paper briefly referred to the 
work of Koblrausch in connexion with the zero conductiy ity 
of dilute solutions. His conclusions were arrived at from a 
study of the temperature variations of conductivity of dilute 
solutions between 0° and 34° C. The question of a lower 
limit to the conductivity has since been attacked by Bousfield 
and Lowry *, who show that the conductivity of dilute 
solutions and the viscosity of water tend towards the same 
limiting temperature, and over the range of temperature (from 
5° to 34° C. ) the temperature variations can be expressed by 
the same kind of curve. They, however, doubt the existence 
of the zero at the point indicated by Professor Kohlrausch and 
Professor Lyle and myself. 
Neither Kohlrauseh nor Beusfield and Lowry used Slotte’s 
form of equation to represent their results, and it has been 
shown by Thorpe and Rodger + that this is the one which 
gives the best values, where a wide range of temperature is 
involved, for viscosity ; and it is probably the best form of 
equation to use in connexion with conductivity results. 
Kunz { conducted some low-temperature experiments with 
strong sulphuric-acid solutions and solutions of other sub- 
stences, and decided that in these cases no zero conductivity 
existed at the temperature supposed. 
Kohlrausch§ has recently studied the temperature 
variations of ionic mobilities, and has here introduced the 
idea that ions in solutions are surrounded by watery atmo- 
spheres carried along with them, and the resistance the ions 
* Bousfield & Lowry, Roy. Soc. Proc. p. 42, June 19, 1902, 
+ Thorpe & Rodger, Phil. Trans. 1894. 
t Kunz, Compt. Rend. vol. exxxv. p. 788 (1902). 
§ Kohlrausch, Sitz. Ber. d. Berlin, Akad. p. 572 (1902). 
Phil. Mag. 8. 6. Vol. 7. No. 41. May 1904. 2 L 
