518 Proceedings of Poyal Society of Edinburgh. 
Percentage 
Free Acid. 
h 2 so 4 
Na 2 S0 4 
(Observed.) 
(Calculated.) 
0*025 + 
0*1 
62-1 
62*9 
0*05 
67*3 
67*4 
0*1 
73*2 
73*1 
0*2 
80*9 
79*6 
0*35 
84*0 
84*9 
Fig. 4. 
Lithium Sulphate. 
The experimental results for solutions containing sulphuric acid 
and lithium sulphate were treated exactly as the preceding. The 
values of the constant K were first obtained by means of the same 
expression with the same exponent, and from them a correcting 
factor determined as before. The value of the exponent y in the 
latter was 0*365, practically identical with that for sodium 
sulphate. It appears, therefore, that the equilibrium in this 
case is represented by an expression of the same form and con- 
taining the same exponents as before. 
The next tables give all the data for the calculation of the most 
probable value of the constant A 1} which completely determines 
the expression for the equilibrium. 
