552 Intelligence and ^Miscellaneous Articles. 



the precipitate in phosphoric acid. By evaporation the salt is ob- 

 tained in small prismatic crystals, which are very soluble in water, 

 but insoluble in alcohol. This salt consists of — 



Phosphoric acid . 48*98 to 49- 17 



Protoxide of manganese 25*42... 24*60 



Water of hydratation . 13*24 ... 12*77 



Water of crystallization 13*19 ... 13*24 



100*83 99*78 



The water of crystallization is dissipated between 230° and 248° F. 



Trisphosphate of Manganese. — This salt is obtained by precipitating 

 sulphate of manganese with common phosphate of soda. It is a 

 white light powder, very slightly soluble in water and perfectly 

 amorphous. 



M. Heintz found the trisphosphate of manganese to consist of — 



Phosphoric acid 29*32 to 29 



Oxide of manganese 43*91 ... 43 



Water expelled between 230° and 248° F. 15*95 ... 15 



Water expelled by calcination 11*^2 ..11 



82 

 66 



85 

 12 



100*50 100*45 



Ammoniaco-diphosphate of Manganese. — When a solution of sul- 

 phate of manganese containing ammonia and its hydrochlorate is 

 gradually dropped into an ammoniacal solution of phosphate of soda, 

 a viscid precipitate is produced, which after some time is converted 

 into crystalline scales. This is Otto's salt. Analysis gave — 



Otto. Heintz. 



Phosphoric acid 37*86 38*37 



Oxide of manganese .... 37*84 38*35 



Ammonia 9*16 1 «, r , 



Water 15*14 / Jtiai 



100*00 100*23 



Diphosphate of Manganese. — A solution of sulphate of manganese 

 is to be rendered acid by acetic, hydrochloric or phosphoric acid, 

 and to this is to be added common phosphate of soda until the pre- 

 cipitate, which at first disappears, becomes permanent, some man- 

 ganese remaining in solution. By standing, this precipitate is con- 

 verted into a reddish crystalline mass, which is but slightly soluble 

 in water, but readily so in acids. 



This salt contains — 



Phosphoric acid 34*61 to 34*86 



Oxide of manganese 34*58 ... 34 43 



Water expelled between 230° and 248°F. 23*30... 22*05 



Water expelled at 392° 423... 4*23 



Water expelled by calcination 4*38 ... 4*38 



101*10 99*95 



Journ. de Ph. et de Ch., Novembre 1848. 



