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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 surrounding 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 quantity of earth which 
enters, as a constituent part, into the composition 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 commonly 
applied; Cannel coal being the provincial expression for Candle 
eoal ; candle in the Lancashire dialect being pronounced cannel; the 
high degree of inflammability possessed by this substance having 
obtained for it this distinction. The coal called Seotch coal, from its 
being obtained from Scotland, possesses similar properties. It is 
obtained in large solid compact masses, and contains nearly as large 
a proportion of bitumen ; it flames almost as freely as the former, 
and bm-ns 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 stratmn 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. 
