SECT. IX. The Third Reafon, and an Experiment.

BUT Thirdly, We fee yet farther, that the Air likewife is not proper or adapted in all its Parts in general, for the fupplying of Fire or Flame, but that certain determinate Parts of the fame are required thereto; from whence it likewife feems to appear, that we muft form a more limited Notion of Fire, than to think it merely a Motion of fome Parts, provided the fame be but fwift enough, and that it is very probable, that Fire being maintain'd by fome particular Subftance, does confift of particular Parts, and has therefore a diftin& Nature of its own. For which purpofe, let any one make the following Experiment:

We took an eight-corner'd Bottle ADE (Tab. XVI. Fig. 3.) cutting off the Bottom of it, and then put a Candle, fet upon a flat Piece of Board, under it; the Ends of which Board D and E ftood out beyond the Edge of the Glafs, that they might not be driven up into it when the Glafs was let down a's far as BC in the Water: And we then obferved;

I. That the Candle being lighted, remained burning as in a Lantern, while the Air flowed in by feveral little Holes, that it found between the Board DE, and the Glass.

H. But putting the Bottle into Water as high as BC, whereby all the Paffages for the Air were ftopp'd, the Candle burnt about 20 Seconds, and then went out because the Warmth of the Candle driving the Air out of the Mouth A, the Flame loft its Food.

III. A crooked Tin Tube HK F, which was not very large, being put into the Glass, there feemed new Air to be derived to it by the Candle,

but

but we found however, that after it had burnt between 21 and 22 Seconds, it went out again.

IV. To fee therefore if this did not likewife happen thro' want of Air, which, as it was protruded before the Mouth A, might likewife find its Paffage by the other Mouth of the Tube FK H, as foon as it was fufficiently rarified by the Warmth of the Candle, we took a pair of Bellows LH, blowing continually fresh Air therewith into the Tube, and by the Tube into the Bottle; where-, upon we obferved the Candle burning as bright as ever before, whilft fuch blowing lafted.

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V. But that which is very remarkable, was, that when inftead of the Bellows we blew into the Tube at H, with the Mouth, fome Air which had been a while in the Lungs, we found the Candle did not burn above ten Seconds; and confequently not near fo long as when it had no fresh Air at all: This is a plain Sign, that the Air in our Lungs lofes that Property which render'd it fit to feed the Flame, and that Flame and the Breath of Men seem to require the fame kind of

Air.

VI. This is the more confirmed, forafmuch as when we fuffer'd the Air to go no farther than the Mouth, and not to defcend into the Lungs, and by quick and frequent Breathings, conveyed the fame into the Tube, the Candle would continue burning, tho' not fo bright as when we used the Bellows, which fupplied it with more and fresher Air.

VII. Having put a little Wax-light in the Place of the Candle, we found that by leaving the crooked Tube in the Bottle open, the faid Light burnt 170 Seconds.

From all which it may be inferr'd with great Appearance of Truth, that the Air in general is VOL. II. 002

not

not only neceffary to Fire, but even, that fome particular Parts thereof are only proper for it; and confequently, if it be not eafie to prove, yet it is very probable, that Fire is likewise a particular Subftance or Matter. For if it had wanted nothing more than that fine Element or Principle; which fome Philofophers have fuppofed, and befides them only fome coarfer Particles, be they what they will, fo that they could by the faid Matter only be continued in Motion; it does not feem that either of thefe were wanting here, even at the time when the Candle was extinguifhed. For of the latter fort, there was enough remaining in the Candle it felf; and according to thefe Philofophers, the other fine Matter may with less Refistance come at the Flame through the Pores of the Glafs, than through the Air it felf. Is this likewife by Chance, that whereas Fire does ftand in need of a continual Afflux of particular Particles of the Air, the faid Particles are always at hand, and are endowed with juft fuch a Property as will feed almost all kinds of Fires? How comes it then, that they dare not likewise maintain, that the Fitness of the Teeth and Pinions of a Wheel, a Clock, or a Mill, or the Wards of the Key for a Lock, which it is to open, are formed without the Contrivance of the Workman? Since the Ends and Pupofes for which they are used, fall infinitely fhort in comparison of those great Benefits which the Aptitude of Air and Fire to each other do derive to Mankind.

SECT.

SECT. X, and XI. The Fourth Reason, and Experi

ments.

IF now, Fourthly, we can fhew by Experiments, that that which we discover in Contemplating Fire has a great Analogy and Likenefs to the Effects of Water and Air, with refpect to the Matters that are diffolved therein; we fhall learn farther, that thofe Philofophers feem to come neareft to the Truth, who maintain, that Fire is a particular Matter, or a Menftruum, as the Chymifts phrase it, capable of unbinding, that is, of dividing or feparating very many and almost all Bodies that are known to us; after the fame manner, for inftance, as Water acts upon Salt, and Aquafortis upon Iron. So that the burning of moft Bodies is no otherwise performed, than by the melting of fome of the Parts thereof in the Flame. For which reafon, if there be many Fire-Particles in fuch Bodies, as Wood, Turf, or the like, they help to encrease the Flame when they are let loose by burning; and when none of these are to be met with in Bodies, or when they can't be unbound, the Flame is not encreas'd thereby, but thofe Bodies are only melted and render'd fluid in the fame manner as we fee Afhes and Metals melted in the Fire, which don't burn, but are turned to Glafs. And as other Menftruums do either not diffolve fome Bodies wholly, or not in a long while; fo we find fome, but very few, Bodies that are capable of refifting the Power of Fire after it has long operated upon them.

Those that defire to fee fome Examples of this kind of Effects of Fire, need only confult the Writings of Chymifts about them; and to fave them trouble, we fhall prefent them with fome few.

'Tis known, that if one put Salt of Tartar and pounded Antimony in Water together, that Salt will take hold of the Antimony in a little time, unite itself in that Menftruum with the Sulphur thereof, as the Chymifts delight to call it. After the fame manner we find, that the faid Salt of Tartar unites itself with the Sulphur of Antimony when diffolved in Fire, as before it had partly been in Water. Now the faid Chymifts know, that whether Fire or Water be chofen for a Menftruum, a Mixture of the fame Properties will refult from this Salt and Antimony; and every one may fee the fame by putting Vinegar to both.

Thus we fee the fame Effects refulting indifferently from Fire and Water in other Chymical Operations; fuch as Coagulations or Precipitations, as they are called by Chymifts; the Regulus Antimonii being mingled with its Sulphur in Antimony, by the means of Salt of Tartar, that unites itself in the faid Sulphur, is feparated from it by Fire, and finks to the Bottom after the fame manner as Steel united with the Sulphur-Copperas, when this last is diffolved in Water, and fo in many other Cafes.

Thus we find alfo, that the Flame of a Candle is always blue and transparent at Bottom, but much whiter at Top, because more Parts of the Cotton and Tallow are there mingled in the Flame, which is render'd thicker thereby; juft after the fame manner as when any thick Matter is mingled with the Water, which will be cleareft where there is a lefs Quantity of fuch Matter, and thickeft or most troubled where the Matter moftly abounds. So likewife, when you kindle a Brimftone Match, the Flame proceeding from the Brimftone will appear at firft blue and tranfparent, bur fo foon as the Stick or Card, which it cover'd, are diffolved, the Confufion of the Parts of both Bedies will render the fame thicker and whiter presently.

Infinite