Constant of Tee and Alcohol at very Low Temperatures. 13 



The observations with same condenser having frozen alcohol as 

 the dielectric are as follows : — 



Table VIII. — Brass Condenser filled with Absolute Ethylic Alcohol 

 frozen and reduced to —185° C. 



Deflection of 

 galvanometer 

 when in charge 

 circuit. 



Deflection of 

 galvanometer 

 when in discbarge 

 circuit. 



Voltage on 

 terminals of 

 condenser. 



Mean 

 galvanometer 

 deflection. 



12 -20 cm. 

 12-10 „ 

 12-10 „ 



12-80 cm. 

 12 -50 „ 

 12-50 „ 



50-5 volts 

 )> >> 



3> . >> 



12-5 cm. 

 12-3 „ 

 12 3 „ 



Mean galvanometer deflection = 1260. 

 Mean voltage = 50*5. 



Galvanometer deflection corrected for capacity of glass separators and also of 

 contact breaker, and reduced to correspond to a voltage of 101*1 = 24665. 



Since the corrected capacity of the condenser when at — 185° C. 

 and filled with gaseous air at —185° C. is represented by the number 

 7*905 = 8-39— 0-07-0-415, we have for the dielectric constant of 

 solid alcohol at -185° C. the value 24*665/7*905 = 312. 



In addition to measuring the dielectric constants, the same experi- 

 mental arrangements enabled lis to measure approximately the 

 dielectric resistance of the ice and frozen alcohol at and from the 

 temperature of —185° C, and the following tables give the approxi- 

 mate total resistance of the condenser when the dielectric consisted 

 of these substances and was slowly allowed to heat up from 

 -185° C. 



Table IX. — Variation in the Resistance of an Ice Condenser heated 

 up from -185° C. = -200° pt. to about 70° C. Temperatures 

 given in platinum degrees by standard platinum thermometer P x . 



Temperature of 



the ice in 

 platinum degrees. 



-200*0° 

 -1722 

 -135-0 

 -126*0 

 -108-4 

 -98-8 

 -95*2 

 -93-2 



Resistance of 

 the ice condenser 

 in megohms. 



26200-0 

 5670-0 

 1570-0 

 11300 

 706-0 

 470 

 353-0 

 282-0 



