SCHLTJNDT — DIELECTRIC CONSTANTS OF PURE SOLVENTS. 369 



One scries of measurements was made which gave the value 

 11.7 for its D. C. at 19° C. 



Iso-propyl Nitrite. — A sample of iso-propyl nitrite, prob- 

 ably not entirely free from nitrous acid, was measured. The 

 value 11.5 was found for its D. C. at 19° C. 



Ethyl Uretliane. — The sample used for the measurements was 

 kindly furnished by the School of Pharmacy of this University. 

 Its melting-point was 48° C. The value found for the D. C. 

 of the liquid compound at 60° was 13.6 ; the solid form gave the 

 value 3.18 at 23° C. 



Amylsulph-hydrate. — The boiling point of the sample was 

 116.5° C. under 752 mm. of pressure. The D. C. found was 

 4.35 at 22° C. 



INORGANIC SOLVENTS. 



Phosphorus Trichloride. — The sample used was of Kahl- 

 baum's manufacture. It was redistilled, boiling at 74.1° C. 

 under a pressure of 740 mm. The average of two determina- 

 tions gave the value 3.36 for its D. C. at 22° C. No absorption 

 was observed. 



Arsenic Trichloride. — The sample which served for the 

 measurements had been prepared in this laboratory by Dr. 

 Lincoln. It was dried with fused calcium chloride and was 

 redistilled. The sample used boiled from 127° — 128° C. un- 

 der 740 mm. of pressure. The value 12.35 was obtained for 

 its D. C. at 21° C. Slight absorption which was doubtless due 

 to conduction was observed. 



Antiraony Trichloride. — The sample used for the measure- 

 ments conducted about as well in the fused state, at 70° C, as a 

 fiftieth normal sodium choride solution. The position for max- 

 imum resonance was still well enough defined without increas- 

 ing the intensity of the oscillations in the secondary circuit, but 

 the absorption was more marked than with arsenic trichloride. 

 Hence it seemed advisable to determine the D. C. by the 

 method outlined by Drude 1 for substances which show absorp- 



3 See Drude Zeit. phys. Cherc. 23, pp. 294-297. 



