168 Dr TURNER'S Chemical Examination 



According to this analysis, 100 parts of the ore contain 



Protoxide 86*94 



Oxygen 9*851 



Water 0*949 



Baryta ...... 2*260 



Silica a trace. 



100-000 



Now 86*94 : 9*851 : : 36 : 4*079 ; and as the presence of water 

 and baryta, from the small quantity of these substances, must be 

 regarded rather as accidental than essential to the mixture, it fol- 

 lows that Braunite is an anhydrous deutoxide of manganese. 

 I apprehend the baryta must be in combination with deutoxide 

 of manganese ; since, were it united with peroxide, the loss in 

 oxygen would exceed the quantity above stated. 



I am not acquainted with any analysis of this mineral by 

 other chemists. 



Analysis of the Pyramidal Manganese-ore or Hausmannite. 



Hausmannite, before being washed, yields a faint odour of 

 chlorine by the action of sulphuric acid. When heated to red- 

 ness it gives off 0*435 per cent of water ; and at a white heat the 

 loss is only 0*65 per cent, indicating 0*215 of oxygen. When 

 dissolved in muriatic acid, a small quantity of silica is left, 

 amounting to 0*337 per cent ; and on adding sulphuric acid to 

 the solution, a little sulphate of baryta subsides, indicating 0*111 

 per cent of the pure earth. Hausmannite is accordingly resolved 

 by this analysis into 



