OF I HON OF NEW JERSEY. 83 



Protoxide of Iron. The means which the Judge 

 used were insufficient to shew the existence of Phos- 

 phoric acid, which is one of its essential constituents. 

 For a description of this mineral the reader is referred 

 to the above work, and to the mineralogy of Professor 

 Cleaveland. 



'This mineral was analysed as an hydrated proto- 

 phosphate of Iron, a preliminary examination having 

 shewn that it contained no other substances. 



A. 5 Grammes of the mineral were dissolved in 

 nitro-muriatic acid with heat. Water was then added 

 to dilute the liquor, and the iron was thrown down 

 by ammonia, in union with the phosphoric acid ; the 

 precipitate separated from the liquor by filtering was 

 washed and calcined : the resulting liquor was set 

 by for future examination. 



B. In order to decompose the ferruginous phos- 

 phate, it was treated with three times its weight of 

 caustic potash, at a red heat, in a silver crucible, the 

 mixture was constantly stirred and maintained at that 

 temperature for half an hour ; after cooling, it was 

 diluted with water and filtered. As one fusion does 

 not always free the oxide of iron from phosporic acid, 

 it was again fused with another portion of that alkali, 

 asrain diluted and filtered. The oxide of iron was 

 well washed with water acidulated with acetic acid, 

 to separate it from the potash, then dried and cal- 

 cined. It weighed %A% grammes. As the iron in 



