8 Enumeration of Simple [Book t. 



7. Coal * or Carbon, the bafis of fixablc air. 



8. The unknown radicals of the muriatic, fluoric, 

 and boracic acids. 



9. The fixed alkalis. 



10. Earths. 



11. Metals. 



"The different earths which are as yet known to phi- 

 .Jofophers are, 



1. Calcareous, or earth of lime, 



2. Silicious, or earth of flints. 



3. Argillaceous, or clay. 



4. Magnelia. 



5. Barytes, or ponderous earth. 



To thefe later mineralogifts have added, 



6. The Scottjlh, or Strpnthian earth, 



7. Thejargonic. 



8. The adamantine. 



Whether all or mod of thefe may not be refolvable 

 into the five principal earths may yet be doubted ; and 

 thus far is certain, that all of them are exceedingly 

 fcarce: the Scottifti however is the moft common. 



The metals again are fubdivided into. 



1. Arfenic. 



2. Molibdena. 



3. Nickel. 



4. Cobalt. 



* More properly charcoal, for our common pit-coal is a hete- 

 fogeneous mafs, containing much foreign matter, as may be feen 

 Book VI. c. 37. I have however employed the generic term 

 ccal, becaufe charcoal, though much the purefl of thefe bodies, is 

 in this country coftfidered not as a natural but a faftitious fub- 

 ftance. 



5. Bifmuth, 



