DOMAIN VI. CARBONACEOUS. 



STRUCTURE I. FIBROUS. 



Aspect 1. Entire. Bovey coal. 



Surturbrand, from Iceland. 



Fibrous lignite, from France, Liguria, c. 



Aspect 2. Mingled. Bovey coal, with resinas- 

 phalt. 



Lignite, with ambe'r, from Prussia. 



STRUCTURE II. FRIABLE. 



From the south of France. 



STRUCTURE III. EARTHY. 



Aspect 1. Entire. Umber or earth of Co- 

 logne. 



Aspect 2. Mingled. The same, with nuts re- 

 sembling the areqa. 



With a gum which burns like frankincense. 



Having thus described the ESSENTIAL ROCKS, 

 or those which receive their divisions and deno- 

 minations from preponderant or from predomi- 

 nant substances, whence they might also be 



