Iron. . 27,5 



ihapelefs mafles, or in a ftaladitical form, or 

 even cryftalized in regular forms according to 

 GmeHn y though Mr. Ddljle denies it : in 

 fome places it forms whole mountains ; it 

 affords from 40 to 80 per cent, of iron. Ac- 

 cording to Mr Gerhard it contains argill, 

 for he extracted alum from it. Mr. Hklm 

 found it alfo to contain manganefe. 



SPECIES VIII. 



Hematites In a loofe form, mixed with a notable 

 Proportion of ArgilL 



H matitical yellow^ red and 6rown Ochres. 



13. Ochres are diftinguifhed from clays 

 by containing a larger proportion of martial 

 particles ; thofe that become brown by calci- 

 nation, and alfo magnetic, belong to this 

 fpecies ; fometimes the ferruginous particles 

 are mixed with argill, and calcareous or mu- 

 riatic earths, and then thefe ochres effervefee 

 with acids. 



SPECIES IX, 



Red Calx of Iron combined with Plumbago. 

 "Red Eifen Glimmer, Eifenrahm and Eifenman. 



14. This differs from the black in this, 

 that it is not magnetic before tor refaction. 



T 3 SPECIES 



