16 
MK. W. CASSIE ON THE EFFECT OF TEMPERATURE ON 
Fig. 8. 
If the relation indicated by Cleer Maxwell’s electromagnetic theory of light held 
good, and the specific inductive capacity were ecjual to the square of the refractive 
index, then the rate of change of specific inductive capacity with temperature ought 
to be twice that of the refractive index. Amongst the liquids, for which Dale and 
Gladstone have observed the refractive indices at difterent temperatures, are four of 
those dealt with here. The mean rates of change, with tenqjeratui'e of the refractive 
index for the A line in the spectrum, deduced from their observations, are 
