240 Proceedings of Royal Society of Edinburgh. [sess. 
parison of his curves ; * it is plain, however, that experiments over 
a much wider range of concentration are required before any 
satisfactory conclusions can be reached. 
Electkic Conductivity at 0° C. 
The equivalent conductivities of dilute solutions of chloride, 
bromide, iodide of a metal are practically the same at 18° C., though 
concentrated solutions do show small differences. In order to see 
if greater differences exist at a lower temperature, we have deter- 
mined the conductivity of all the solutions employed in the 
viscosity experiments at 0° C. The method was the usual 
Kohlrausch alternating current method, with bridge and telephone. 
The results are corrected for the slight variations in temperature, 
and the cell constant was determined by means of the value at 0° C. 
of 1 n KC1, as given in Kohlrausch ( Leitvermogen , p. 204). 
Whetham f has recently determined the conductivity of a 
number of solutions at 0° C., potassium chloride being one of them : 
for 1 n KC1 (1*2 n was the most concentrated solution employed) 
he found A = 69'0. There is also in Kohlrausch (Leitvermogen, p. 
199) a table of temperature coefficients of conductivity for dilute 
solutions of HC1, KC1, KI, as determined by Deguisne. 
Table VI. 
Mol. per litre. Equivalent conductivity. 
KC1 1 65*4 
2 63T 
3 62-4 
KBr 1 68*3 
2 67-6 
3 65-8 
KI 1 70-0 
2 69-5 
3 68*0 
HC1 1 187-0 
2 165-7 
3 143-5 
HBr 1 203-0 
2 175-0 
3 148-3 
* These are viscosity-percentage concentration curves, and are not compar- 
able, as are viscosity-molecular concentration curves, 
t Proc. Roy. Soe., 71, p. 332 (1903). 
