2^6 
In the grounds at Benwell, about a quarter of a mile north of 
the river Tyne, a coal mine took fire at a workman’s candle, negli- 
gently placed, and continued burning about thirty years, though 
at first so small, that a proposal was made to put it out for so low 
a reward as half-a-crown, but it was not accepted. It afterwards 
acquired such force and strength, Mr. Wallis says, from the kindled 
sulphurs and bitumens, that it raged with fury, in various directions 
and depths ; sometimes taking its course east and west, and at last 
to the north, into the grounds of Fenham, near a mile from its first 
appearance: committing great ravages in its way; and being onlv 
conspicuous by its flame, and columns of smoke, in the night. Tlie 
eruptions at Fenham were in nearly twenty places*. 
Nor is it from accidents only that combustions of this kind 
occur. Mr. Williams states that, within a mile of Kirkaldy, in 
Scotland, in a great plain, called Dysart Moor, the coal, which 
is there found in plenty, burns almost spontaneously— Sometimes 
flames are seen in the night, and a black smoke in the day ^The 
inhabitants say, that at approach of storms, dreadful hissing noises 
are heard from the holes and caverns, with a considerable discharge 
of flame. Nor is it beds of coal only, that a slow combustion would 
convert to mineral coal, as Mr. Kirwan calls this charred coal; 
since a similar substance might probably be formed by the burning 
of peat, the stratum covering which might so regulate its burning, 
as to secure its charring. In addition to the instances, mentioned 
in a former Letter, of these accidents, I will relate one, mentioned 
by Abbe Fortis, who says, “ Not many years ago, a fen, near the 
village of Ostrovizza, was struck with lightning, and, its bottom 
being turf, it burned a long time under ground, though the fire was 
visible only in the night ; after it was extinguished, the whole fen 
remained black, and the upper soil became barren ■f'.” 
* The Natural History of Northumberland, vol. i. p. 132. 
f Travels in Dalmatia, p. 37. 
