98 Elements of Mineralogy. 



65 of filex, 1 6 of argil], 5 of iron, the 



remaining 14 gr. were diflipated. 



SPECIES XIV. 



Arglll mixed with a notable Proportion of red 

 Calx of Iron y andfometimes Steatites. 



Red Ctialk. 



It hardens in fire, and then often becomes 

 magnetic , in the ftrongeft heat it melts into 

 a black glafs, which does not corrode the 

 crucibles, as calcareous ores do: it affords 

 1 6 or 18 per cent, of iron; if it does not 

 become magnetic it affords only from 7 to 14 

 per cent. Rinman Hiftoria Ferri, 189. 



Compound Species in 'which the Argillaceous 

 Genus predominates. 



SPECIES I. 



Compounds of the different Species of the Ar- 

 gillaceous Genus. 



I. VARIETY. 

 Micaceous Marl. 



II. VARIETY. 

 Micaceous Shiftus, either Slate or Flag-ftone* 



HI. VARIETY, 



