COAL. 35 



abundant quantity. Further west, in Ohio and 

 Pennsylvania, it has been discovered, and I am 

 confident that it exists in the vicinity of this can a], 

 The reasons which induce this opinion are vari- 

 ous and conclusive, and 1 shall now enumerate 

 some of them. 



Coal is composed of charcoal, or carbon, bitu- 

 men, some portion of earth, and generally a small 

 quantity ofmetalic matter. When it exists with- 

 out bitumen, it is termed anthracite or glance coal. 

 All the western coal contains bitumen, and gene- 

 rally speaking, the coal found cast of the moun- 

 tains is without it. 



Coal is found in hilly situations, under strata of 

 grit, which is a compound of sand and clay, or 

 under schistus which is an indurated clay, splitting 

 into layers and forming either slate, or a substance 

 called shivers, according to its fracture. Coal 

 frequently alternates with strata ofgrit, stone and 

 schistus. Its roof is generally composed of shale ; 

 and although in the island of Great Britain it is 

 not intermingled with lime stone, which generally 

 forms the outlines of coal fields, yet on the conti- 

 nent they are often found in company. 



Discarding the theories which have been stated 

 respecting the origin of coal, whether of min< 

 or vegetable derivation, it is sufficient merely to 

 state facts in order to sustain the opinion which 1 

 have advanced on this subject. 





