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Show FR FR A Glafs Veffel then IA full of Water to ‘A, being immerg’d in a Veffel of Water mix’d with Salt GH KL, the Water prefently rifes from D to C; which feems owing to the fudden Conftru@ion of the Veffel, haftily plung’d into fo cold a Medium: Soon after from the Point C it continually defcends condenfing,till it arrives at the Point F ; where for fome time it feems to remain at Reft : But it foon recovers it felf, and begins to expand, rifing from F to E, and from thence foonafter, by one violent Leap, mounts to B; and here-the Water in I is immediately feen all thick and cloudy, and in the very Inftant of this Leap is converted into Ice. Add, that while the Ice is growing harder, and fome of the Water near the Neck ofthe Veffel I is freezing, the Flux of the Water is continu’d above B towards A, and at length runs out at the Veffel. APTA [Pe WASH OA Sb a ae ne dihs tn adly, That theylofe not only of the {pecifick, but alfo of their abfolute Gravity by freexiag ; fo that when they are thaw’d again, they are found confiderably heavier than before. 3dly, That frozen Water is not quite fo tranfparent as whenit was liquid; and that Bodies don’t perfpire fo freely through it. 4thly, That Water, when frozen, evapo- rates almoft as much as when fluid. To fome one of thefe Principles, all the Syftems of Freezing are reducible, The Cartefians explicate Freezing by the Recefs or going out ofthe Etherial Matter from the Pores of the Water, or other Liquor; which being once done, the finer Parts aretoo {mall and flexible to keep the long, flender and Eel-like Particles of Water fluent, or in the Form of a Liquor. But the Corpufcularians, or Gaffendifts, af. cribe the freezing of Water, with more Probability, to the Ingrefs of Multitudes ofcold or frigorifick Particles, as they call them, which entring the Liquor in Streams, and difperfing themfelves every Way thro’ it, do crowd into the Pores of the Water, and hinder the wonted Agitation ofits Parts, and wedgeit up, as it were, into the hardor confiftent Body of Ice; and from hence proceeds its Increafe of Dimenfions, Coldnefs, &c. That Ice is fpecifically lighter than the Water out of whichit is by freezing made, is certain by its {wimming in it; and that this Lightnefs of Ice proceeds from thofe numerous Bubbles which are produc’d in it byits Con- gelation is equally plain - But how thofe Bubles come to be generated in freezing, and what Subftance they contain in them, if they are not quite empty, isan Inquiry ofgreat Importance, and, perhaps, if difcover'd, may contribute much to the underftanding the Nature of Gold. j Mr. Hobbs will have it common Air, which intruding into the Water in Congelation, intangles it felf with the Particles of the Fluid, be requires the Prefence and Contiguity of prevents their Motion, and produces thole sii, numerous Bubbles, thus expanding its Bulk, 6thly, That Water which has been boil’d, andrendering it {pecificallylighter. does not freeze fo readily as that which has But in anfwer to this, no fuch Ingrefs of not. Air into Water appears in its Coagulation; qthly, That Water being cover’d over with and that it does not get into frozen Oil is a Surface ofOil of Olives, does not freeze fo plain, becaufe that Body is condens’ d by bereadily as it does without it; and that Nut ing frozen. Oilabfolutelypreferves icunder a ftrong Froft, _ And Mr. Boyle has alfo fhewn, by utwhen Olive Oi! will not. doubted Experiments, that Water will freeze 8thly, That Spirit of Wine, Nut Oil, and in Veflels hermetically feal’d, and into bral Oil of Turpentine do not freeze at all. Bodies or Veflels clofely ftopt, and into which gthly, That the Surface of the Water in the Air can have no Ingre{s, hath yet been sthly, That Water does not freeze in vacuo, freesing appears all wrinkled; the Wrinkles being fometimes in Parallel Lines, and fome- times like Rays, proceeding from a Centre to the Circumference. s . ig, or the Method of accounting for thefe Phenomena are very many. The chief Principles that different Authors have gone upon, are either, that fome foreign Matter is introduc’d within the Pores of the Fluid, by means of whichit is fix’d, its Bulk increas'd, (c. Or that fome Matter which was naturally contain’d in the Fluid, is now expell’d; by reafon of the Abfence of which the Body becomes fluid, &c. , Orthat there is fome Alteration produc’d in “ Eres oe either of the Particles of he Fluidditit felf, or of fomethi mething that i tain’d withinit. ee turn’d into Ice, abounding with thefe Bubbles as numerous as in thofe frozen in the open Air. _He alfo has prov’d by Experiment, that Water kepta while in the exhaufted Receivery till allits Bubbles were emerg’dand gone,be- ing afterwards turn’d into Ice by a freexiig Mixture, the Ice had fcarce any Bubbles in it: Whence it is plain, that thefe Bubbles are fill’d with fome Matter which is within the Water, if they are fill’d with any thing: But he proves alfo, by plain Experiments, that they have none, or exceedingly little crue cla {tick Air contain’d in them. Others, and thofe ofthe greateft Number; are of Opinion, that the freezing Matter is 4 Salt; and they argne, that an Excefs of Cold will render Water torpid, but never congealit without Salt: They fay, that thofe Particles that are the chief Caufe of freezing, are Saline FR FR Saline mix’d in a due Proportion, Conge- the Air, or rather an Alteration in the Spring lation bearing a near Relation to Cryftallization. This Salt is f{uppos’d to be of the nitrous Kind, and to be furnifh’d by the Air, which is generally found to abound in Nitre. It is indeed no difficule Matter to account for the Particles of Nitre preventing the Fluidity of Water. Thefe Particles are fuppos’d to be fo manyrigid pointed Spicula, which are eafily impell’d, or driven into the Stamina or Globules of Water; which by this means becoming varioufly mingled, and intangled with it, do by degrees weaken and deftroy the Motionof it. The Reafon that this Effe& arifes only in fevere Winter Weather,is, that it is then only that the retraG@ing AGion of the nitrous Spicula is more than equal to the Poweror Prin- ciple, by which the Fluid is otherwife kept in Motion, or difpos’d for Motion. Several Experiments ofartificial Freezing fupport this Opinion. Forif you mix a Quantity of commonSaltPetre with Snow, or Ice pulveriz’d, and diffolve the Mixture in the Fire, and then im— merge a Tube full of Water in the Solution, the Water, thar Part of ic next the Mixture, will freeze prefently, even in a warm Air. Whence they argue, that the Spicula of the Salt is driven through the Pores of the Glafs, and mix’d with the Water, by the Gravity of the Mixture and of the incumbent Air: For that it is evident that the Salt has this Effect, inafmuch as it is certainly known, that the Particles of Water cannot find their Way through the Pores ofthe Glafs. In thefe artificial Freezings, in whatever rt the Mixture is apply’d, there is prefently in or Lamma ofIce produc’d, whether at the Top, Bottom, or Sides, by reafon that there is always a Stock offaline Corpufcles fufficient to overpower thefe Particles of Fire; but xzatural Congelations are confin’d to the Top of the Water, where the laft moft abounds. it this Syftem is oppos’d by the Author of andit is allow’d, that each Particle of Air has the Virtue of a Spring: And hence thisAuthor argues, that the {mall Springs of grofs Air mix’d with Water, have more Force in cold Winter Weather, and do then anbend them- felves more than at other Times: Hence thofe Springs thus unbending themfelves on one Side, and the external Air continuing to prefs the Surface of the Water on the other, the Particles of the Water being thus conftring’d and lock’d up together, muft lofe their Motion and Fluidity, and form a hard confiftent Body, till a Relaxation of the Spring of the Air from an Increafe of Heat, reduce the Particles to their old Dimenfions, and leave Room for the Globules to fow again. But this Syftem feems to be built upon 2 falfe Principle; for the Spring or Elafticity of the Air is not increas'd by Cold, but diminifh’d: Air condenfes by Cold, and expands irs felf by Heat; and it’ is demonftrable in Pneumaticks, that the elaftick Force of ex— panded Air is of that to the fame Air as con- dens’d, as the Bulk when rarefied is to its Bulk when condens’d. Indeed, fome Authors, in order to account for the Increafe of the Bulk and Dimenfion of the f{pecifick Gravity of frozen Water, have advanc’d as follows, viz. That the aqueous Particles in their natural State were nearly Cubes, and fo fill’d their Space without the Interpofition of many Pores; but that they are chang’d from Cubes to Spheres by Congelation: From whence it will neceffarily fol- Jow, that there muft be a great deal of empty Space between them. But in oppofition to this Hypothefis, the Nature of Fluidity and Firmnefs eafily fuggefts,that {pherical Particles are much properer to confticute a Fluid than cubical ones, and le(s difpos’d to-form a fix’d than cubick one. pour expliquer la Nature But after all, in order to come at a con- Glace, who objeéts that it does not ap- fiftent Theory of Freezing, we muft either have Recourfe to the frigorick Matterofthe I 2 and Force of the Air, is the Caufe of this clofer Union of Water. It is evident from Experiment, that there are an infinite Number of Particles of grof{s Air interfpers’d among the Globules of Water, ong pear, that Nitre al enters the Compofition of Ice; but if it did, it would fall fhort of accounting for fome of the principal Effedis ; as, Howfhould the Particles of Nitre, by en¢ e Pores of the Water, and fixing the , caufe the Water to dilate, and render it fpecifically lighter? Theyfhould naturally augment its Weighr. This, and fome other Difficulties thew the ty of anew Theory, and therefore the nor advances this which follows, ch feems to folve the Phenomena in a manple, as not deing upon the Admiffion or Extrufion of ous eterogene Matter. hat Water freezes in the Winteronly, be- aufe its Parts then being more clofely join’d together, do mutually embarrafs one another, nd lofe al] the Motion they had; and thas Corpufcularians, confider'd under the new Light and Advantages of the Newtonian Philofophy, or to the Aitherial Matter of the Cartefians, under the Improvements of Monf. Gauteron. The true Canfe of Freezing, or the Conge- lation of Water into Ice, fay the former, feems plainly to be the Introduction of the fri-~ gorifick Particles into the Pores or Interftices betweenthe Particles of the Water,andby that meansgetting fonearthem, as to be juft within the Spheres of one another’s artraéting Force, and then they muft cohere into one folid or firm Body. But Heat afterwards feparating them, and putting themintovarious Motions, breaks this Union, and feparates the Particles fo far from one another, that they get out of the Diftance of the atrrafting Force, and into the Verge ofthe repelling Force, |