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coal appear to be, that jet is found in detached masses, whilst 

 Cannel coal is deposited in strata ; and that jet, once set on fire, 

 continues to flame for a considerable time, a bituminous vapour 

 being at the same time exhaled ; whilst Cannel coal requires to be 

 so disposed, that its combustion may be aided by that of the sur- 

 rounding fire, and by an increased rapidity of the accession of air. 

 The difference between the chemical phenomena yielded by this 

 substance and by jet appears to depend chiefly on the greater quan** 

 tity of earth which enters, as a constituent part, into the composi- 

 tion of Cannel coal than into that of jet. The terra ampelitis of the 

 ancients has been supposed by many to have been the substance 

 we are here treating of; but the term seems, most generally, to have 

 been applied to that species of loose bituminous earth which exists 

 in those parts, in which fluid bitumens have prevailed. 



The coal possessing these properties, and which is obtained from 

 Lancashire, is that to which the term Cannel coal is most com- 

 monly applied ; Cannel coal being the provincial expression for 

 Candle coal; candle in the Lancashire dialect being pronounced 

 cannel ; the high degree of inflammability possessed by this sub- 

 stance having obtained for it this distinction. The coal called 

 Scotch coal, from its being obtained from Scotland, possesses similar 

 properties. It is obtained in large solid compact masses, and con- 

 tains nearly as large a proportion of bitumen ; it flames almost as 

 freely as the former, and burns away to a white ash. 



The Cannel coal of Wigan in Lancashire, the most beautiful coal 

 of this species, is found, according to Mr. Godefroy de Villetaneuse, 

 at the depth of seventy-six yards from the surface of the rock ; over 

 which is a stratum of earth, from three to eight yards in thickness. 

 The first stratum of the rock, he states, to be two feet in thickness ; 

 laying on a metallic stone of a deep blue colour, forty-six yards 

 thick. Underneath this is a vein of common coal, five feet in thick- 

 ness ; and thirty yards beneath this is found the Cannel coal, the 

 thickness of which is one yard two inches. 



