NATURAL PHILOSOPHY.

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consequence of there not being a sufficiency of dry materialintervening between the earth on which hay stands and thehav itself; when it will be discovered that the caloric occa-sioned by the congregated vegetable has drawn the humidityfrom the earth, occasioning what is known as moukly hay,which appears as the first step towards its actual and finaldecomposition. But if the process be suffered to proceed,the heat soon considerably augments, the vapour becomessmoky, and actual flames soon burst forth, when the wholemass is presently reduced to ashes.

“ The remarkable and frequent evolution of heat justspoken of,” he says, “ demands an inquiry whether anything similar ever takes place in the process of bituminiza-tion; since if that be not the case, the parallel would fail.”But as the process of bituminization is carried on out of thereach of ordinary examination, it is impossible, as previouslyobserved, to speak correctly as to the phenomena whichtake place in its process.” However, to prove that theefl'ects are similar, he cites a letter from Peter Collinsoq,Esq. to Sir Hans Sloane , among the imprinted papers ofthe Royal Society preserved in the British Museum , whichshows that this phenomenon may arise during the process.This writer, it appears, accounted for the occurrence uponsimilar principles to those which our author has adopted.“ Our newspapers, printed here, mention the burning of“ brooks in the vale of Good Cheap; but the case is, that“ some pieces of marshy ground, called brooks, from their“ watery situation, have flamed for some time; and these“ they have called burning brooks; the parish next adjoin-“ ing is also called Brooks. The soil is like those parts“ of Cambridgeshire where the turf is cut, and very often“ under water; but this dry season has brought it from very“ wet to that degree of moisture which often causes hay to“ ferment and take fire. Accordingly this fire begins“ about four feet under ground, just above the water, (as“ appears by digging,) and so burns up to the surface where“ it flames out, especially if stirred by any thing; and“ according to the quantity of roots and peat it meets with,“ it leaves strata of black coal or red ashes. The fire has“ now burnt for several weeks, and is expected to continue“ till rain or springs extinguish it. The same land burnt“ about forty years ago. Perhaps this hypothesis of its“ kindling by fermentation, may be confirmed by the fre-“ quent firing of hay-stacks this year, of which we have“ many more instances than in several years before.”

He then cites the authority of Schoockius, whence, it islearnt, that this species of combustion is no rare occurrence