IRON. COBALT. NICKEL. 



Ferrous sulphide, precipitated 

 from ferrous solutions by ammonium 

 sulphide. 



Ferrous hydroxide passing into 

 ferric hydroxide. Ferrous solutions 

 precipitated by alkali hydroxides. 



Ferric hydroxide, precipitated 

 from ferric solutions by alkali hydrox- 

 ides. 



Ferrous solutions, precipitated 

 by potassium ferrocyanide. 



Ferric solutions, precipitated by 

 potassium ferrocyanide, or, Ferrous 

 solutions precipitated by potassium 

 ferricyanide. 



Ferric solutions, treated with 

 alkali sulphocyanates. 



Cobaltous carbonate, precipita- 

 ted from cobaitous solutions by so- 

 dium carbonate. 



Nickeloits carbonate, precipita- 

 ted from nickelous solutions by sodium 

 carbonate. 



