ferves not for a pabulum to nourish t for a vehicle to arreft and bring it Which feems the fole ufe of oil, air, o thing, that vulgarly paffeth for a pabul of that element. 198. To explain this matter more to be obferved, that fire, in order to fible, must have fome fubject to act being penetrated and agitated by fi with light, heat, or fome other fenfib And this fubject fo wrought upon m culinary fire. In the focus of a burni pofed to the fun, there is real actual not difcerned by the fenfe, till it hath work on, and can fhew itfelf in it's ing, flaming, melting, and the like. nited body is, in the foregoing fense, But it will not therefore follow, that tible into pure elementary fire. Th that appears, may be ingenerable and by the course of nature. It may be f prifoned in a compound (a), and yet ture, though loft to fenfe, and though to the invifible elementary mafs, upo of the compounded body: as is mani lution of ftone lime by water. 199. It fhould feem, therefore, tha of air's being the pabulum of fire, verted into fire, ought to be under this sense; to wit, that air being lefs ther bodies, is of a middle nature, more fit to receive the impreffions of rial fire (b), and impart them to othe cording to the antients, foul ferveth fo (b) 163 (a) 169, 192. 193. but view. other food 7, it is This fects us teration. be called glafs ex though newhat to cts, heat Every ig linary fire. is converfor ought corruptible ed and im tain it's na It return in the analyfis ft in the fo what is faid - being con Food only in grofs than o and therefore a fine æthe things. Ac or a vehicle to intellect (a), and light or fire for a vehicle to the foul, and, in like manner, air may be fuppofed a vehicle to fire, fixing it in fome degree, and communicating it's effects to other bodies. 200. The pure invifible fire or æther doth permeate all bodies, even the hardest and most folid, as the diamond. This alone, therefore, cannot, as fome learned men have fuppofed, be the cause of mufcular motion, by a mere impulfe of the nerves communicated from the brain to the membranes of the muscles, and thereby to the enclosed æther, whose expanfive motion, being by that means increafed, is thought to fwell the mufcles, and cause a contraction of the fleshy fibres. This, it fhould feem, the pure æther cannot do immediately, and of itself, because, fuppofing it's expansive motion to be increased, it muft ftill pafs through the membranes, and confequently not fwell them, inafmuch as æther is fuppofed freely to pervade the moft folid bodies. It fhould feem therefore, that this effect must be owing, not to pure æther, but to æther in fome part fixed and arrested by the particles of air. 201. Although this æther be extremely elastic, yet, as it is fometimes found by experience to be attracted, imprisoned and detained in grofs bodies (b), fo we may fuppofe it to be attracted, and its expansive force diminished, though it fhould not be quite fixed, by the loofe particles of air, which combining and cohering therewith may bring it down, and qualify it for intercourse with groffer things. Pure fire may be faid to animate air, and air other things. Pure fire is invifible; therefore flame is not pure fire. Air is neceffary both to life and flame. And it is found by experi ment, that air lofeth in the lungs the feeding flame. Hence it is concluded, fame thing in air contributes both to life Vital flame furvives culinary flame in vac fore it requires lefs of that thing to fufta 202. What this may be, whether fo proportion, or fome peculiar parts of not easy to say. But thus much feems whatever is afcribed to acid may be al to fire or æther. The particles of æthe der with the greatest force: therefore, ag Sir Ifaac Newton's doctrine, when united attract each other with the greatest force fore they conftitute the acid. For. ftrongly attracts and is attracted, may b acid, as Sir Ifaac Newton informs us in h acido. Hence it should seem, that the Homberg, and the acid of Sir Ifaac a tom one and the fame thing, to wit, p æther. 203. The vital flame or æthereal fpi attracted and imprisoned in groffer bodies to be fet free and carried off, by the fu traction of a fubtil and pure flame. H haps it is, that lightening kills animals, fpirituous liquors vapid in an inftant. 204. Hippocrates in his book conce Heart obferveth, that the foul of man is rifhed by meats and drinks from the lo but by a pure and luminous substance d rays, and diftributing a non-natural nourif he terms it, in like manner as that fro teftines is diftributed to all parts of the bod luminous non-natural nourishment, thou fecreted from the blood, is exprefly fa come from the lower belly. It is plain, he thought it came into the blood either by refpiration, or by attraction through the pores. And it must be acknowledged, that fomewhat igneous or æthereal brought by the air into the blood feems to nourish, though not the foul itself, yet the interior tunicle of the foul, the auraï fimplicis ignem. 205. That there is really fuch a thing as vital flame, actually kindled, nourish'd, and extinguish'd like common flame, and by the fame means, is an opinion of fome moderns, particularly of Doctor Willis in his tract De fanguinis accenfione: that it requires conftant eventilation, through the trachea and pores of the body, for the discharge of a fu liginous and excrementitious vapour: and that this vital flame, being extremely fubtil, might not be feen any more than fhining flies or ignes fatui by day-light. And yet it hath fometimes become vifible on divers perfons, of which there are undoubted inftances. This is Dr. Willis's notion: and perhaps there may be fome truth in this, if it be fo understood, as that light or fire might indeed conftitute the animal spirit or immediate vehicle of the foul. 206. There have not been wanting thofe, who, not content to fuppofe light the moft pure and refined of all corporeal beings, have gone farther, and bestowed upon it fome attributes of a yet higher nature. Julianus the Platonic philofopher, as cited by Ficinus, faith, it was a doctrine in the theology of the Phoenicians, that there is diffused throughout the univerfe, a pellucid and fhining nature pure and impaffive, the act of a pure intelligence. And Ficinus himself undertakes to prove, that light is incorporeal, by feveral arguments: Because it enlightens and fills a great space in an inftant, and without oppofition: Because feveral lights lights meet without refifting each other light cannot be defiled by filth of any caufe the folar light is not fixed in an Laftly, because it contracts and expand eafily without collifion, condenfation, or delay throughout the vafteft fpace. fons are given by Ficinus, in his comm firft book of the fecond Ennead of Plot . 207. But it is now well known, moves, that it's motion is not inftantar it is capable of condensation, rarefaction fion that it can be mixed with other ter their compofition, and increase their All which feems fufficiently to overt arguments of Ficinus, and fhew light poreal. There appears indeed fome firft fight, about the non-refiftance of ticles of light occurring one to another fible directions or from all points. Par we suppose the hollow furface of a la ftudded with eyes looking inwards one it may perhaps feem hard to conceive, rays from every eye fhould arrive at eve without juftling, repelling, and confor other. 208. But thefe difficulties may be confidering in the first place, that v are not mathematical points, and c that we are not to fuppofe every poin radiating point. Secondly, by grantin rays do refift and intercept each othe ftanding which the act of vision may ed. Since as every point of the ob feen, fo it is not neceffary that rays fuch point arrive at the eye. W (a) 169, 192, 193. |