as from those of the Fire itfelf, one may fee there that fome of those Bodies being wholly fhut up in Glafs, became heavier only by the pure Flames of Brimftone, or of Spirit of Wine; which could not happen otherwife than from the fmall Fire-Particles that must first have penetrated the narrow Pores of the Glafs. [See the faid Boyle de penetrabilitate Vitri à ponder. part. Flam.]

SECT. XIV. Fire will likewife cleave to Water; proved by Experiments.

IV. Now that Fire can likewise join itself to Water, may be fhewn by fetting a Glafs, or rather a little Tea-Cup (to prevent the breaking of it) full of very hot Water under the Receiver of an Air Pump; when you will often fee at the very first Exhauftion, if the Water be hot enough, or at least at the fecond or third, fo great a Motion in the Water, that, like boiling Water, it will run over the Brims of the Veffel. This Experiment may be very easily made by all that use Air-Pumps.

When we tried this upon the 24th of December, 1705, there was a little. Glafs full of cold Water put under the Receiver at the fame time, which, according to Cuftom, did indeed difclofe a few Bladders or Air-Bubbles, but no kind of Motion that was any ways comparable to that of hot Water; fo that this laft Motion feems to be more properly owing to the Fire than to the Water.

But to be affured thereof, and to fatisfie the Objection, whether the Heat of the Air might not likewife be the cause of this more violent Mo-. tion in the hot Water, on the 21st of January, 1706, we heated fome Lye, in which there is no Air, and put it into a little Glafs under the Receiver; and to prevent the Pump from being fpoiled, if it fhould chance to run over, we put the firft Glafs into a

fecond:

fecond: And we obferv'd upon the fecond turn of the Pump (tho there was no Alteration at the first) that the Lye, with a fudden burfting, flew out above both the Glaffes; which can only be afcribed to the Particles of Fire contained in it; forafmuch as no Air ever mingles itself with this kind of Liquor.

After wards, upon the 7th of June, 1709, making the fame Experiment again with Water, we filled two equal Tea Cups at the fame time with boiling Water; and putting one of 'em under the Receiver, we found that the Receiver itself, upon taking off the Preffure of the Air, and during the Motion of the Water, was very hot at the Top. Now, whether this proceeded from hence, that the Fire Particles being freed from the Preffure of the Air, and extricating themselves by their Motion from the Water, rifing up to the Top, and paffing thro' the Glafs, render'd it hotter there than in any other Place; or, whether it be only to be ascribed to the Vapours, we fhall not here difpute; but this is true, that the Water, which had undergone fo many Motions in the Receiver, being taken out from thence, was much colder even to the touch of all that were then prefent, than that which was never put under it: Whereas, if it be supposed, that the Heat were caufed alone by a greater Motion of the Parts of the Liquor, and not fingly by those of the Fire, the Water that had been under the Receiver, and had been put into fuch violent Motion, fhould have been much hotter than that which had fuffer'd none.

And thus it feems to appear from hence, that the Water under the Receiver had therefore loít more of its Heat than the other, because the FireParticles, by taking away the Preffure of the Air, got an Opportunity of freeing themfelves by their Ff2

own

own Motion from the Water, from whence, being flown out, the Water remained lefs warm than that other, in which the preffure of the Air had hinder'd the Fire Particles from feparating themfelves fo fuddenly from the Water.

Now whether this adhefion of the Particles of Fire to Water may likewife be fuppposed to contribute fomething, and to be the caufe either alone or jointly, of that Property of the Water whereby it extinguishes the Fire, I fhall not examine any farther here; forafmuch as the giving a true Reason of fuch Extinction, as common, and therefore as unheeded as it may appear to many, does (if I may speak my Mind freely in the Matter) require a great deal of Confideration.

SECT. XV. Three Confequences from the laft Experiment.

To proceed; I have noted three Things, that feem to follow from the abovemention'd Experiment.

Firft, That as Water and Air are particular Subftances, it seems, that we might conclude from hence, that Fire alfo fhould be efteemed as fuch; and not be look'd upon, confider'd as only a fwifter Motion of the Parts of all other Bodies. This may be inferr'd from the Waters becoming colder, afterit has been just put into Motion, as has been fhewn, therefore need not be here repeated. It likewife feems to appear from hence, that cold and hot Water being at the fame time put under the Receiver, and the Preffure of the Air remov'd, the hot Water, immediately after its great Motion, did not fhew the leaft moving Particles, whereas there were feveral Stirrings obferved in the cold, by the Rarefaction of Air, a good while after. Now 'tis known, that by Boiling and Heat, the Air flies

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out of the Water, fo that thefe Rifings and Ebullitions feem not to be imputable to any other Caufe than to the Fire-Particles that fucceed and cleave to the Water, and which, by flying away, leave the Water at rest.

Secondly, From hence it likewife feems to appear, that the Fire-Particles are very Elaftical and Expanfive: Forafmuch as we fee, that by removing only the Preffure of the Air that keeps them down, they exert their Motion of their own accord, which is alfo a Property of an Elaftick Body.

Thirdly, The laft thing that may be inferr'd from this Experiment, and may likewife be of use, is, that the Fire which fticks close to the Water, as foon as it comes into an Air which is thinner and lefs powerful in its Preffure, abandons the Water and flies away from it,

SECT. XVI. Water and Fire feem to produce a Compofition lighter then Air.

FROM all this it is to be observed, that Fire and Water being united and mingled together, may make a Compofition lighter than fo much Air, and which can afcend in it; just as Iron and Cork being faften'd together, will float upon the Water, tho' the Iron be heavier than the faid Water. I remember to have feen an Experiment very analogous to this, by throwing a Clod or Lump of unrefined Brimftone, and letting it fink in Lye, to discover whether it contained as much Air in it as Salt-petre, in which we found a great deal; but having taken off the Preffure of the impendent Air, we did not only fee fome little Bubbles fwelling up, but what is chiefly remarkable here, fome of the little Bits of Brimftone that were broken off, were driven upwards

Ff3

by

by these Bubbles, and when they burst, the Brimftone funk down again. I have obferved the fame when Water was thrown into Salt, and the Preffure of the Air removed. From whence may be inferr'd, that a lighter fluid Matter may joyn itfelf to a heavier, and make one Compound therewith, and afcend and float in a Liquor, in which the heavier, being alone, would fink. Thus Experience likewife teaches us, that a fmall Heat, and confequently a little Fire, can make Water evaporate and rife upwards, even without boiling; And fo we alfo fee all volatile Salts, fuch as those of Sal-Armoniac, of Hartfhorn, &c. afcending by the Warmth of a Fire that is hardly fenfible. The fame does happen too in pure burning Spirits, and in all other things that are esteemed the most volatile by the Chymifts.

And if this Adhesion of the Particles of Fire to thefe Matters, be not the only Cause thereof, it may at least be fuppofed from what has been faid before, that it may be reckon'd a concurrent Caufe: And it even feems to be more credible, that this Cause is more common than that by which the Water, before it is capable of turning itself into Vapours, muft be rarified into a nine or ten times greater heighth, length and breadth : Which is no ways, at leaft very rarely, experienced in Substances that evaporate with so small a Heat; and in others, fuch as Volatile Salts, can hardly be fuppofed to happen.

SECT. XVII. Water must be divided into exceeding Small Particles, in order to be Evaporated.

THE laft thing that is required above all the reft, as being the chiefeft Occafion of the Rifing of Water into the Air, is, that it fhould be divided