418 



SMITHSONIA^' MISCELLANEOUS COLLECTIONS 



VOL. 54 



In 1850 Maumeiie s ^ results appeared. He dissolved pure iron wii'e 

 in aqua regia, preciiDitated with ammonia, filtered off the precipitate, 

 washed thoroughly, ignited and weighed after the usual methods of 

 quantitative analysis. The percentages of Fe in FBoOs are given in the 

 third column : 



1.482 grm. Fe gave 2.117 grm. FeoOj. 



1.452 " 2.074 



1.3585 " 1.941 



1.420 " 2.0285 



1.492 " 2.1315 



1.554 " 2.220 



Mean, 70.0008, ± .0019 



Hence Fe = 56.003. 



The two determinations hy Eivot " are quite unimportant. This chemist 

 reduced ferric oxide in hydrogen, and obtained the subjoined per- 

 centages of iron : 



69.31 

 69.35 



Mean, 69.33, ± .0130 



Hence Fe = 54.25. 



Eichards and Baxter ^ also reduced ferric oxide by hydrogen. Iron 

 was purified electrolytically and then converted into oxide by two proc- 

 esses. First, by solution, precipitation as hydroxide, and ignition of the 

 latter compound. With the oxide thus prepared, the two subjoined re- 

 ductions were made : 



Fe.Os. 

 3.17485 

 3.01235 



Fe. 

 2.22096 

 2.52750 



Per cent. Fe. 

 69.954 

 69.968 



Mean, 69.961, ± .0047 



Hence Fe = 55.900. 



Secondly, iron was converted into nitrate, and that into oxide by 



calcination. The oxide was free from occluded gases, 

 vacuum weights for both series, are as follows: 



The data, with 



1 Compt. Rend., Oct. 17, 1850. 



2 Ann. Cheiti. Pharm., 78, 214. 1851. 



' Proc. Amer. Acad., 35, 253. Zeitsch. anorg. Cheni. 



23, 245. 1900. 



