Page images

192. 20

table, and metallic fulphurs impart different quali. ties to the same acid salt ? Can this be explained upon Homberg's principles ? And are we not obo. liged to suppose, that light separated by the attracting and repelling powers in the strainers, ducts, and pores of those bodies, forms several distinct kinds of sulphur, all which, before such feparation, were lost and blended together, in one common mass of light or fire seemingly homogeneous.

192. In the analysis of inflammable bodies, the fire or fulphur is lost, and the diminution of weight seweth the loss (a). Oil is resolved into water, earth, and salt, none of which is inflammable. But the fire or vinculum which connected those things, and gave the form of oil, escapes from the artist. It disappears, but is not destroyed. Light or fire imprisoned made part of the compound, gave union to the other parts, and form to the whole. But having escaped, it mingles with the general ocean of æther, till being again parted and attracted, it enters and specificates fome new subject, of the animal, vegetable, or mineral kingdom. Fire therefore in the sense of philofo. phers is also fire, though not always flame.

193. Solar fire or light, in calcining certain bodies, is observed to add to their weight. There is therefore no doubt but light can be fixed, and enter the composition of a body. And though it should lye latent for a long time, yet, being fet free from its prison, it shall still thew itself to be fire. Lead, tin, or regulus of antimony, being exposed to the fire of a burning glass, though they lose much in smoak and steam, are nevertheless found to be considerably increased in weight, which proves the introduction of light or fire in..

(a) i69.


to their pores. It is also observed, that urine produceth no phosphorus, unless it be long exposed to the solar light. From all which it may be concluded, that bodies attract and fix the light; whence it should seem, as some have observed, that fire without burning is an ingredient in many things, as water without wetting.

194. Of this there cannot be a better proof, than the experiment of Monsieur Homberg, who made gold of mercury, by introducing light into its pores, but at such trouble and expence, that I fuppose no body will try the experiment for profit. By this junction of light and mercury, both bodies became fixed, and produced a third different from either, to wit, real gold. For the truth of which fact, I refer to the memoirs of the French academy of Sciences. From the foregoing experiment it appears, that gold is only a mass of mercury penetrated and cemented by the substance of light, the particles of those bodies attracting and fixing each other. This seems to have been not altogether unknown to former philofophers ; Marsilius Ficinus the Platonist, in his commentary on the first book of the second Ennead of Plotinus, and others likewise before him, regard. ing mercury as the mother, and sulphur as the fa. ther of metals; and Plato himself in his Timæus describing gold, to be a dense fluid with a shining yellow light, which well suits a composition of light and mercury.

195. Fire or light mixeth with all bodies (a), even with water; witness the flashing lights in the sea, whose waves seem frequently all on fire. Its operations are various according to its kind, quantity, and degree of vehemence. One degree ...fa) 157.


keeps water fuid, another turns it into elastic air (a). And air itself seems to be nothing else but vapours and exhalations, rendered elastic by fire. Nothing flames but oil: and sulphur with water, salt, and earth compose oil ; which sulphur is fire : therefore fire enclosed attracts fire, and causeth the bodies whose composition it enters to burn and blaze.

196. Fire collected in the focus of a glass ope. rates in vacuo, and therefore is thought not" to need air to support it. Calx of lead hath gone off with an explosion in vacuo, which Niewenty't and others take for a proof that fire can burn without air. But Mr. Hales attributes this effect to air enclosed in the red lead, and perhaps too in the receiver, which cannot be perfectly exhausted. When common lead is put into the fire in order to make red-lead, a greater weight of this comes out than was put in of common lead. Therefore the red-lead should seem impregnated with fire. Mr. Hales thinks it is with air. The vast expansion of compound aqua fortis, Mr. Niewenty’t will have to proceed from fire alone. Mr. Hales contends. that air must necessarily co-operate. Though by: Niewentyt's experiment it should seem, the pholphorus burns equally, with and without air.

197. Perhaps they who hold the opposite sides in this question, may be reconciled by observing that air is in reality nothing more than particles of wet and dry bodies volatilised, and rendered elastic by fire (6). Whatever therefore is done by air must be ascribed to fire, which fire is a subtile invisible thing, whose operation is not to be difcerned but by means of some grofler body, which

exhauh in

der Weio, the

(a) 149.

fb) 147, 150, 151,

M 2


ferves' not, for a pabulum to nourish the fire, but for a vehicle to arrest and bring it into view. Which seems the sole use of oil, air, or any other thing, that vulgarly pafseth for a pabulum or food of that element.

198. To explain this matter more clearly, it is to be observed, that fire, in order to become sen-' sible, must have some subject to act upon. This being penetrated and agitated by fire affects us with light, heat, or some other sensible alteration.: . And this fubject fo wrought upon may be called culinary fire. In the focus of a burning glass ex- ' posed to the sun, there is real actual fire, though not discerned by the sense, till it hath somewhat to work on, and can fhew itself in it's effects, heating, flaming, melting, and the like. Every ignited body is, in the foregoing sense, culinary fire, But it will not therefore follow, that it is convertible into pure elementary fire. This, for ought that appears, may be ingenerable and incorruptible by the course of nature. It may be fixed and imprisoned in a compound (a), and yet retain it's nature, though lost to sense, and though it return in. to the invisible elementary mafs, upon the analysis of the compounded body: as is manifest in the folution of stone lime by water..

199. It should seem, therefore, that what is faid of air's being the pabulum of fire, or being converted into fire, ought to be understood only in this sense ; to wit, that air being less gross than other bodies, is of a middle nature, and therefore more fit to receive the impressions of a fine ætherial fire (6), and impart them to other things. ACcording to the antients, foul serveth for a vehicle to

(a) 169, 192. 193.

(b) 163.


intellect (a), and light or fire for a vehicle to the soul ; and, in like manner, air may be supposed a vehicle to fire, fixing it in some degree, and communicating it's effects to other bodies.

200. The pure invisible fire or æther doth permeace all bodies, even the hardest and most solid, as the diamond. This alone, therefore, cannot, as some learned men have supposed, be the cause of muscular motion, by a mere impulse of the nerves communicated from the brain to the membranes of the muscles, and thereby to the enclosed æther, whose expansive motion, being by that ineans increased, is thought to swell the muscles, and cause a contraction of the fleshy fibres. This, it should seem, the pure 'æther cannot do immediately, and of itself, because, supposing it's expansive motion to be increased, it must still pass through the membranes, and consequently not swell them, inasmuch as æther is supposed freely to pervade the most solid bodies. It should seem therefore, that this effect must be owing, not to pure æther, but to æther in some part fixed and arrested by the particles of air.

201. Although this æther be extremely elastic, yet, as it is sometimes found by experience to be attracted, imprisoned and detained in gross bodies (6), so we may suppose it to be attracted, and, its expansive force diminished, though it should not be quite fixed, by the loose particles of air, which combining and cohering therewith may bring it down, and qualify it for intercourse with groffer things. Pure fire may be said to animate air, and air other things. Pure fire is invisible; therefore fame is not pure fire. Air is necessary both to life and flame. And it is found by experi

[blocks in formation]


« EelmineJätka »