OF ARTS AND SCIENCES. 65 



dissolve easily in hot water free from saline matter, but do not crys- 

 tallize readily from the solution. Of this salt, after careful washing 

 and drying only, 



0.7744 gr. lost with WO.Na^ 0.1859 gr. = 24.01 % NHg + H„0. The 



oxygen gained by the vanadic dioxide is 2.14'^ and 24.01 -[- 



2.14 = 26.15% NH3 + H,0 

 0.5556 gr. gave when heated in a combustion tube 0.1451 gr. = 



26.11% NH3 + H.O 

 0.8969 gr. gave with KMnO, 0.2001 gr. VO, = 22.31% 

 0.2018 gr. " " 0.0444 gr. " =22.19% 



0.5626 gr. after reduction with SOgH^gave with KMnO^ 0.2427 gr. = 



43.13% VA 

 0.2494 gr. after reduction with SOgHj gave with KMnO^ 0.1067 gr. = 



42.76% V2O5 

 0.5325 gr. gave 0.0326 gr. (NHJ2O = 6.13% 

 0.5053 gr. » 0.0309 gr. " =6.12% 



The mean of the two determinations of VO2 is 22.25%, and the 

 equivalent in VjO. 24.38%, which, subtracted from 42.76 and 43.13 

 respectively gives 18.38 and 18.75 for the percentages of VoOg. 



The analyses correspond closely with the formula 



5987 100.00 



A portion of the very dark green salt was boiled with water, and the 

 deep green solution allowed to stand, when much lighter green crystals 

 separated. These were again dissolved and recrystallized. The crys- 

 tals had a peculiar rusty olive-green surface color. Of this salt, 



0.4770 gr. gave 0.1013 gr. V2O, by KMnO^ = 21.21% and 



0.1014 gr. V02 = 21.22% 



0.4014 gr. gave 0.0249 gr. (NHJ2O = 6.20% 



0.3062 gr. lost with WO^Naj 0.0663 gr. = 21.65% 



VOL. XXI. (n. 8. XIII.) 5 



