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bark, and here and there adorned with their leaves. The wood was 
inflammable, making a strong fire, and serving instead of fossil coals. 
Dr. Plott, in his History of Oxfordshire, relates, that the scarcity 
of firing, in some parts of that county, has induced the people to 
burn a sort of black substance, of a grain somewhat like rotten 
wood, half burnt ; partaking also of a mineral nature, and therefore 
called by authors metallophyton, or lignum fossile. Put into water, 
it will not swim ; and into fire, it consumes but slowly, and sends 
forth very unpleasant fumes. A vein of it, at Ducklington, looked 
like wood; yet broken, shewed a smooth and shining superficies, 
not unlike to stone pitch ; and put into the fire has not near so ill a 
smell. The doctor, who fully believed in the frolics of the stone- 
forming archeseus, says, as to the substance of lignum fossile, it is 
thought to be a cretaceous earth, turned to what it is by subter- 
raneous heats ; for that it was never formerly wood, notwithstanding 
its specious and outward likeness, is plain from its never being 
found with roots or boughs, or any other signs of wood*. 
Dr. Morton, who likewise did not believe in the subterranean 
change and preservation of organized matter, describes two or three 
species of this metallophytonf , one of which, he says, is of a dark 
colour, and has a grain ; for in one direction (which is usually ac- 
cording to the length of the pieces) it cleaves or parts pretty readily 
into plates and splinters ; the other way it snaps into shorter pieces, 
and will not cleave at all. There is another sort, which does not so 
readily part into the flakes. None of these are found in any large 
masses. They are all, more or less, of a glossy black, and have a 
density or smoothness within, like that of bitumen, or jet. In that 
also they resemble, as he remarks, the true bitumen, or pisasphalton. 
They are not so firm and hard as the common coal, and are much 
* The Natural History of Oxfordshire, by Dr. Plott, p. 65. 
f The Natural History of Northamptonshire, by Dr. Morton, p. 121 
