Constant of Ice and Alcohol at very Low Temperature*. 

 Fi&. 2. 



I I 1 I I I _J I 



-200- -190 -180- —170 -ISO- -150- -140- - ISO- 



I ember- at ure in PlaUnum degrees . 



The broad general result which emerges from these experiments is 

 that at a temperature of — 185° C. we find a value for the dielectric 

 constant for ice, when using relatively very slow reversals of 

 electromotive force, which is not very different from that found by 

 observers using reversals of many millions per second by the use of 

 electrical oscillations or waves, when working at temperatures of 

 0° C. or a little below. 



C, B. Thwing ('Zeits. Phys. Chem.,' vol. 14, 1894), using an 

 electrical resonance method, has examined tbe variation of the 

 dielectric constant of water with temperatures from 0° C. to 88° C, 

 and found a maximum value of 85*2 at or near the temperature of 

 maximum density of water. 



It seems therefore to be a matter of some importance to measure 

 the dielectric constant of ice at all temperatures from the lowest 

 which can be reached up to 0° C, using various frequencies of alter- 

 nating electromotive force, and to explore the mode of variation of the 

 dielectric constant with temperature and with frequency throughout 

 this range. The point which especially needs to be cleared up is 

 whether the dielectric constant of ice is, or is not, more changed hy 



