- 



PROCEEDINGS OP IIIK A.MI.KK \\ ACADEMY. 



ever, than tint evolved when the same capric oxide was dissolved in >ul- 

 pliiir.i" acid. It \\;i> shown, however, that the gas which resulted upon 

 solution in hydrochloric acid and Btannous chloride consisted wholly ol 

 nitrogen, and thai the volume of this nitrogen corresponded t<» the uitro- 



in the . ■ I free by Bolutii i the same oxide in Bulphuric acid. 



Although ii was evident that the oxygen waa absorbed by the stannous 

 chloride, yet, Bince in the case of all oxides heretofore examined the in- 

 cluded gases consisted chiefly of nitrogen, it is fair to conclude that this 

 so in the case of ferric oxide. Only a trace even of nitrogen was 

 evolved from the ferric oxide, hence this preparation must have been 

 practically free from included 



In order to avoid any error due to hygroscopicity, the oxide u-<< i for 

 each analysis was bottled in dry air in the bottling apparatus, which lias 

 already been described elsewhere.* The platinum boat containing the 

 oxide was heated in the hard glass tube while the air was exhausted from 

 the apparatus by means of a Sprengel ail - pump. Dry air was then 

 admitted, and the boat was pushed into the* weighing bottle which was 

 then Btoppered and weighed with the usual precautions. Since in two 

 instances repetition of the bottling failed to change the weight of the 

 oxide, subsequently this precaution was omitted. 



The oxide was then reduced in the manner already described, constant 

 weight of the metal bein<j attained much more easily than in the ,■;,.,- of 

 oxide prepared from ferric hydrate. Five closely agreeing results were 

 obtained from analyses of material prepared as above. 



SERIES II. 



* These Proceedings, 32, 50 (1890). 



