Drs North on Fuel. ug 
getables. These articles are presumed to be changed by a 
natural charring, or coaling process, into the various and dif- 
ferent kinds of coal which have been found. 
Common firew before itis cut, is known to be living, 
organized matter, which contains charcoal, and the hydroge- 
nous or bituminous principle. The latter, as is well known, 
can be made to disappear by the smotheri evaporating, 
or partial combustion process, which is used in making char- 
coal. 
The various sorts-of firewood, which have grown in the 
open air, contain fewer hurtful extraneous matters, than the 
pecially the former, which contain ie Sisco hurtful ingredi 
ents, are, or may be, more highly charged with the bituminous 
or hydrogenous principle, than is the case, with the more com« 
mon sorts of wood. This is probably occasioned by the peat 
aving grown in water, which is known to contain t1e hydro- 
genous principle in great abundance. Peat, and coal, of 
such a quality, as has just been considered, makes a more 
uniform, mild, and pleasant heat, if not a better fire, than or- 
wood. 
Bituminous fuel, kindles and burns at a low temperature, 
and is attended with much flame, soot, smoke, dust, and ma- 
ny ashes, but has, notwithstanding its inconveniences, been 
used ing a 
a vehement heat is required. But justice and candour make 
it necessary to say, that bituminous fuel, has almost every 
where been the cheapest. 
