26 



PHYSIOGRAPHY. 



Manganese Spar. 



ors, are in general, several tints of green, brown and red, which become 

 darker on exposure to the air. 



2. Heated before the blow-pipe, it becomes dark-brown, and melts into 

 a reddish brown or blackish glass, which in the variety from N, Jersey, 

 is magnetic. With borax, it dissolves into a violet colored glass. Re- 

 duced to powder, and Created with muriatic acid, it is partly dissolved; 

 the insoluble remainder assuming a white color. , 



