Now, if it be allowed, that all matter is effentially the fame, under every poffible diverfity of appear ance; its phænomena exhibit almoft an infinity of modal diverfification. Two effences only (viz. fpirit and matter) are fully fufficient, to account for every appearance, and to answer every known purpose, of creation, and of providence. What occafion, then, for five? or, as fome fuppofe, for no fewer than feven; viz. earth, water, air, fire, light, æther, and fpirit? Might we not, juft as rationally, dream of feventy, or even feventy millions of effences? Sir Ifaac Newton's rule for philofophifing, and the argument on which he grounds it, ftrike me with all the force of self-evidence: Caufas rerum naturalium non plures admitti debere, quàm quæ et veræ fint, & earum phænomenis explicandis fufficiant. Dicunt utique philofophi: Natura nihil agit fruftra ; & fruftra fit, per plura, quod fieri poteft per pauciora. Natura enim fimplex eft, & rerum Caufis fuperfluis non luxuriat. If this be juft, the admiffion of more effences, than two, would be totally inconfiftent with a firit and fundamental principle of all natural knowledge. 2. The four claffes of matter, commonly called Elements, are, in reality, not fimple, but exceedingly compound, bodies; and partake yery much of each other. Which circumftance forms no inconfiderable branch of that alaia, or confufion, literally fo termed; introduced by original fin. Thus, Earth affociates to itself all the folvable fubftances that are committed to its bofom. Which fubftances, after the time refpectively requifite for their folution, and for their co-alefcence with the earth, are not diftinguishable from original earth itself. : Water is known to comprehend every fpecies of earthy particles; as well as to include no fmall portion of air and to be capable, by motion, of affuming that quality which we term heat, even in fuch a degree, as to be no lefs intolerable by animals, than flame itself. Air is conftantly intermingled with an immenfe number of diffimilar particles. With household dust (for instance), which is, in fact, the wearings of almost every thing. Not to mention the countlefs effluvia, with which the atmosphere is charged, inceffantly flying off from animal bodies, both found and putrefcent; and from the whole world of vegetable fubftances, both fragrant and fœtid. These particles, through the continual attrition occafioned by their motion and interference with each other, and by the ambient preffure of the air upon them all, undergo, it is probable, a gradual atomic feparation and, when fufficiently comminuted, become, at laft, a genuine part of that aerial fluid, in which they only floated before. Could we breathe nothing but pure, unmixed air, human health and life would, probably, extend to an extreme length. Fire, or more properly a fiery fubftance, will burn (i. e. communicate a portion of its own motion to), and affimilate, all other contracting ance; it will follow, that what we call fenfible qualities are, rather, modal difcriminations, than real, differences. Let us apply this doctrine to colours. Several contracting bodies, whofe corpufcular co-hefion is not fufficiently clofe and firm to refift the fubtil agency of that infinuating power. But, when its force is exhaufted (i. e. when the inteftine agitation of its parts has forced off all that was volatile; and ceafes, in confequence of having no more to do), what remains? A quantity of particles, equally capable (for ought that appears to the contrary) of being condenfed into earth, or expanded into water, or rarefied into air. Which reminds me, 3. Of the continual tranfmutation of one modified fubftance into another, by the chemical procefs of nature; fometimes affifted, but oftener quite unaffifted, by art; which literal metamorphofis feems to be a grand and fundamental law of this lower world; and, if admitted, furnishes me with an additional argument for the famenefs of matter under all its vaft variety of modes and forms. We may, for example, afk, with the poet: "Where is the duft, that has not been alive? "The moift of human frame the fun exhales: And thus the mysterious wheel of nature goes round; the vast mechanic circulation is kept up; and, by a wonderful, but real, sexwpnois, well-nigh every thing (I fpeak of matter only) becomes every thing, in its turn. So thoroughly perfuaded am I, in my own mind, that all the atoms, particles, and larger portions, of matter, are primarily and intrinfically and effentially homogeneous; that I make no doubt, but a millione is phyfically capable of being rarefied into light, and light phyfically capable of being condenfed into a millitone.-By the way, light is, perhaps, no more than melted air: and air is, perhaps, the never-failing refervoir, which fupplies the fun with materials for its rays. Air is, inconteftibly, a neceffary pabulum of fublunary, and why not of folar, fire? I fhall conclude this excurfive note, with a pertinent paffage from Mr. Boyle in which that profound and judicious naturalift informs us, on the authority of an experiment made by himself, that even water is ultimately convertible into oil, and into fire. "Since the varicus manner of the coalition of feveral corpufcles into one vifible body, is enough to give them a peculiar texture, and thereby fit them to exhibit divers fenfible qualities, and to become a body, fometimes of one denomination, and fometimes of another; it will very naturally follow, that, from the various [but providential] occurfions of thefe innu merable Several neceffary pre-requifites must concur, to imprefs my mind, at firft, with an idea of colour. 1. There must be the prefence of a vifible object: 2. The merable fwarms of little bodies that are moved to and fro in the world, there will be many fitted to flick to one another, and so compofe concretions: and many (though not in the Telf-fame place) disjoined from one another, and agitated apart. And multitudes alfo, that will be driven to affociate themfelves, now with one body, and prefently with another. "And if we alfo confider, on the one fide, that the fizes of the fmall particles may be very various; their figures almoft innumerable; and that if a parcel of matter do but happen to flick to one body, it may give it a new quality; and, if it adhere to another, or hit against fome of its parts, it may conftitute a body of another kind; or if a parcel of matter be knocked off from another, it may, barely by that, leave it, and become, itfelf, of another nature than before: if, I fay, we confider thefe things, on the one fide; and, on the other fide, that (to ufe Lucretius's comparifon) all the innumerable multitude of words, which are contained in all the languages of the world, are made of the various combinations of the twenty-four letters of the alphabet; it will not be hard to conceive, that there may be an incomprehenfible variety of affociations and textures of the minute parts of bodies, and confequently a vast multitude of portions of matter endued with ftore enough of different qualities, to deferve diftinct appellations, though, for want of heedfuinefs and fit words, men have not yet taken fo much notice of their lefs obvious varieties, as to fort them as they deferve, and give them diftinct and proper names. "So that, though I would not fay, that any thing can immediately be made of every thing; as a gold ring, of a wedge of gold; or oil, or fire, of water; yet fince bodies, having but one common matter, can be differenced but by accidents [i. e. by modes and circumftances not effential to their nature as parts of matter at large], which feem, all of them, to be the effects and confequents of local motion; I fee not, why it fhould be abfurd to think, that (at least among inanimate bodies), by the intervention of fome very small addition or fubtraction of matter (which yet, in moft cafes, will not be needed), and of an orderly feries of alterations, difpofing, by degrees, the matter to be tranfmuted, almost of any thing may at length be made any thing. "So, though water cannot, immediately, be tranfmuted into oil, and much lefs into fire; yet, if you nourish certain plants with water alone, as I have done, until they have affimilated a great quantity of water into their own nature, you may, by committing this tranfmuted water (which you may diftinguifh and feparate from that part of the vegetable you first put in) to diftillation in convenient glaffes, obtain, befides other things, a true oil, and a black combuftible 2. The furface of that object must have a certain difpofition, texture, or conftruction, of parts :3. Rays of light muft fall towards, and be returned from, that furface:-4. My organs of fight muft (1.) be of fuch a ftru&ure, and, (2.) be in fo found a ftate, as duly to admit, the impreffion naturally refulting from the above complication of circumftances. Who, that confiders all this, can doubt, a moment, whether the idea of colour, with which my mind is affected, on its perception of an object, depend, as abfolutely, on the ftructure and on the ftate of my eyes, as on the fuperficial difpofition and illumination of the object itfelf? Yea, it depends much more on the former, than on the latter. For, as it has lately been well argued, "If all mankind had jaundiced eyes, they must have been under a neceffity of concluding, that every object was tinged with yellow: and, indeed, according to this new fyftem" [viz. the fyftem which fuppofes that bodies are of the colour they feem to be of], "it would then have been fo; not in appearance only, but alfo in reality! *" Befides; was it to be granted, that "colour is a real, material thing;" fuch conceffion would naturally engender a farther mistake, viz. that at least thofe feven colours, which are denominated original ones, and which appear fo very different from each other, are in fact fo many different effences. But as this conclufion, though forcibly deducible from the premife, would be fraught with abfurdities neither few nor fmail, we may fairly fufpect the premife itself to be untrue. combuflible coal (and confequently fire); both of which may be fo copious, as to leave no juft caufe to fufpect, that they could be any thing near afforded by any little fpirituous parts, which may be prefumed to have been communicated, by that part of the vegetable that is first put into the water, to that far greater part of it which was committed to ditillation." Origin of Forms, &c. p. 61-63. Dr. Pricttley's Examination of Beattie, &c. p. 143. An An objection was lately ftarted in private company, against the doctrine which maintains the univerfal famenefs of matter, as if, upon this hypothefis, it would follow, that "All bodies and all qualities of bodies, are equally eftimable." Nothing, however, can be more frivolous than fuch a fuppofition. It might as plaufibly be alledged, that, "Because all actions, confidered, as actions, are exertions of power; therefore, all actions are equally good." Whereas the modes and effects of action occafion fuch vaft relative differences in actions. themselves that a man of common understanding and virtue cannot long hefitate, what fpecies of action to approve. Thus it is, with regard to bodies, and femblances. For, "Tho' the fame fun, with all-diffufive rays, If a philofophic lady vifits a mercer's fhop with a view to felect the brighteft filk it affords; the fair customer will be naturally led to fix her choice on that, whofe colourings appear, to her, the most elegant and vivid: though he knows that thofe colourings are illufive, and that, in reality, there is no fuch thing as abfolute colour at all. In short, we are fo conftituted, as to receive much more delectable idea, from fome femblances, and from fome combinations of femblances, than from others. And we, with very good reafon, like or diflike accordingly. Though, were our organs contrarily fabricated to what they are; the fame objects, which now give us pleafure, would be fources of pain: and what we now relifh as defirable, and admire as beautiful, would ftrike us as, difguftful and deformed. How |