The Absorption Coefficient of Solution for Monochromatic Radiation. 45 



TABLE 16. Cobalt Sulphate in Water (Figs. 14 and 15) Continued. 



Houstoun has measured two solutions of cobalt sulphate in water. 

 His values are given in table 17, for the sake of comparison. 



TABLE 17. A for Cobalt Sulphate in Water. 



Houstoun's values for A are in general much lower than the values 

 recorded in table 16. His values indicate, however, that A is a con- 

 stant with respect to c at all points in the spectrum, which is in agree- 

 ment with the results of the present work. Plate 21 of the paper by 



