NATURAL PHILOSOPHY.

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moisture to answer the purpose of fermentation; which fer-mentation consists in the action of the leaven producing heat,this bitumen operating on the substance, aided by the variousspecies of air discovered in all exist ing bodies, causes a separa-tion of the vegetable oils, or most unctuous parts of the plants,mhicli unction constitutes a vegetable produce, somewhat similart to the mineral, thepure naphtha of the ancients; the previousoperation producing a fresh substance, called bitumen. Thisbitumen has the power peculiar to all unctuous natures, torender foreign objects, of a vegetable nature also, as wood, ofq ualities similar to its own: one of which appears to be itsleading feature, is the communication of this unctuous prin-ciple to all surrounding objects. Of which bitumen thereare various species of the same generic character, previouslydescribed; denoting, perhaps, its different stages of exist-ence. This original deposition of these substances havingcreated by fermentation, that leaven, as properly termed byMr. Parkinson , a sufficiency of which is at all times remain-ing to impregnate fresh supplies of vegetable substancesconstantly falling into this receptacle, so, in part, is a freshsupply brought in, and a constant fermentation is goingforward.

By way of reconciling an apparent contradiction existingbetween Mr. Parkinson ’s opinion and an hypothesis of Dr.Anderson; the former taking it up on the principle just given,whilst the latter believes the peat moss to be distinct speciesof vegetative perfection, and in its fossil state to be in as higha degree of perfection as that species of vegetation is capa-ble of attaining;—we observe, that the fact is notorious, thattwo substances can produce a third, distinct in its proper-ties from either of its originals; this is so well known, thatit will be superfluous to adduce instances: but since anytwo or more substances unite in the production of a third,or other nature, so they may also produce one analogous totheir own properties, so we regard the substance calledpeat moss to be; whilst it is specifically distinct from everyother species of production: this generating in the peat soilfurnishes an infinity of small fibrous roots, which afford adegree of consistency to the entire mass.

This is, we humbly conceive, the mode by which peatearth is first produced, constantly generated, and suppliesprovided to answer every diminution occasioned by thenecessities of man for this species of fuel,

It is now time to speak of the formation of coal,which we do, taking our data from the same very ingeniousauthor. The opinion of Pliny , and after him of Schoockius,