THE ALUMNI JOURNAL 109 



sulphide, collected, washed with hydrogen-sulphid water, alcohol, 

 carbon disulphide, and finally alcohol. After drying until of con- 

 stant weight, an aliquot portion was oxidized and weighed as 

 Sb,0,. 



For the electrolytic estimation, an electrode of 50 sq. cm. was 

 employed, with a solution of the weighed sample in 45 Cc. of 

 water and 80 Cc. of sodium sulphide solution (sp. gr. 1.13 — 1.15) 

 and 15 Gm. of potassium cyanide. Three hours with a current of 

 1.5 volts and 0.25 ampere at 75° C were sufficient for the complete 

 deposition of the metal. After washing the electrode with water, 

 alcohol and ether, it was dried for 10 minutes at 90°. The same 

 sample was estimated volumetrically according to the U. S. P. 

 process. 



Gravimetric Method. — 



According to the above figures, it will be noted that each method 

 yields concordant results (per cent, of Sb) ; however, they do not 

 agree among one another. As standard we are inclined to accept 

 the gravimetric results, since, according to D. F. Smith (Elec- 

 trolytic Analysis, '07, 177), the electrolytic method yields some- 

 what higher figures than the gravimetric. 



