generated fastning itself as on other occasions we declare very strongly to the sides of the Glass contiguous to its edg as the liquor freezes deeper and deeper this crust of Ice increases in thickness and strength so that the water is included as in a vessel Hermetically sealed betwixt this Ice at the upper part and the sides and bottom of the Glass every where else and consequently the remaining water being uncapable of Congelation without Expansion when the ice is grown strong enough at the top to make it easier for the expansive endeavour of the freezing water to crack the sides or bottom of the Glass then to force up that thick cake of Ice the vessel will be broken how much soever there be of it empty above the surface of the Ice And this Conjecture may be confirmed by these two Particulars the one That when water is frozen in a broad vessel which is too strong to be broken or stretch'd by the frost the surface of the ice contiguous to the Air will be convex or protuberant because that though the glaciation began at the top the thickness and Compactness of the vessel makes it easier for the expansive endeavour to thrust up that cake of ice in those parts of it that are the remoter from the sides whereunto they are strongly fastned then to break so solid a vessel 6. The other Particular is afforded us by that Experiment of ours mention'd in the Vth Title foregoing wherein if a vessel half full of water be made to freez not first at the top but at the bottom that liquor may be turned into ice without danger to the glass But we will now add an Experiment on whose occasion we have set down these Considerations For being inclined to think that the spring of the Air shut up in a vessel stopped will preserve it expanded or at least keep it from considerably shrinking notwithstanding a very great degree of Cold in case the vessel be strong and close enough to fence it from the pressure of the external Air we conjectured that the bare weight of the outward Air added to the Refrigeration of the included Air would not be sufficient to break much weaker glasses then those we have been speaking of And therefore partly to satisfie some ingenious Men that this Conjecture made me dissent from and partly to show the Peripateticks and those that adhere to them in the question under consideration that either the Cold alone cannot always as they teach us contract the Air or that if it do the breaking of well stopp'd glasses in frosty weather is much fitter to evince that there may be a vacuum then that there can be none we made the following Experiment 7. We took three glass-bubbles of differing shapes and sizes which we caused to be blown with a Lamp that to make the Experiment very favourable for our Adversaries we might have them much thinner and consequently weaker then those glasses that are wont to be made use of to keep liquors in and which notwithstanding are wont to be broken though they be not full by the frost These Bubbles when the Air was at a convenient temper within were as easily they might be nimbly seal'd up with care to avoid the heating of the Air in them and being afterwards expos'd sometimes to the Air it self in very frosty weather and sometimes to that greater Cold which is produced by the placing them in a mixture of snow and salt we could not nevertheless find that any one of the three was at all broken or cracked so that in case the included Air were condensed into a lesser room the space it deserted may be concluded empty or else it will hardly appear what 〈◊〉 there can be that Nature should break as the Peripateticks pretend very much stronger glasses in Apothecaries shops to prevent a vacuum 8. Having shown that water it self acquires a considerable Expansion by Cold we will next shew that Aqueous Bodies or those that abound with waterish parts do divers if not 〈◊〉 of them the like We took Eggs and exposing them to a sufficient Degree of Cold we observ'd that when the contain'd liquors were turn'd into Ice they burst the shells asunder so that divers gaping Cracks were to be seen in them as long as they continu'd frozen 9. Milk Urine Rhenish-wine and good spirit of Wine being set to freez in distinct glass Eggs neither of the three former liquors 〈◊〉 observ'd to subside before it began to rise The Event in sum was that the Urine was much longer then either of the two other liquors before it began to swell but rose to a far greater height then they afterwards The Wine did not leave the mark above an inch beneath The Milk ascended about two inches and the Urine by guess six or seven 10. A strong solution of 〈◊〉 Vitriol being put into a Cylindrical Pipe seal'd at one end so that the liquor fill'd the Pipe to the height of about six or eight inches being frozen with snow and salt the congeal'd liquor grew very opacous and look'd as if it had been turn'd or shot into Vitriol save a little that remain'd fluid and transparent near the bottom And this Ice as appeared rose considerably higher then the liquor did before Congelation It were perhaps worth trying whether or no even several Bodies of a stable consistence and durable Texture might not be found to receive some though less manifest Dilatation by excessive Cold. And methinks those who attribute Glaciation to the plentiful Ingress of frigorifick Atoms into Bodies should by their Hypothesis have been invited to make some Trials of this kind since we see that the invisible Moisture of the Air against rainy weather does seem manifestly enough to alter the Dimensions of doors window-shuts and other such works made of wood not well season'd And even without supposing the truth of the Epicurean Hypothesis if we consider that in Bread though we are sure that much more water was added to the Meal or Flower then was exhal'd in the Oven yet there appears not the least drop of water distinct in the Concrete and that Harts-horn Sponges and many other Bodies that seem very dry will afford by distillation good store of phlegm or water and more then can probably be ascrib'd to any transmuting Operation of the Fire If I say we consider these and the like things it may seem worth while to try which I want the conveniency to do by accurate measures whether the invisible and interspers'd water its comminution notwithstanding will not upon freezing swell the Body that harbours it And I would the more gladly have been satisfi'd in this because I hop'd it might help me to unriddle a strange 〈◊〉 afforded us by the Narrative of the Dutchmens Voyage to Nova Zembla wherein they relate That the Cold was so great that their Clock was frozen and would not go though they hung more weight upon it then before So that they were
Regards they be far less commodious then either a Watch or Clock Besides that in many cases a skilful Natur alist will by a variety and collation of Experiments make the same discoveries and perform the same things for which others are wont to be beholding to Instruments and perhaps do many things without them that have never been done with them And since Necessity is proverbially allow'd to be the Mother of Inventions even in Tradesmen and Vulgar heads why should we doubt but that the rich and inventive Intellect of a Philosopher may in cases of necestity turn it self and contrive the things it can dispose of into so many differing forms that it will often make its own Sagacity and Industry supply the want of exact Tools and Instruments And these Considerations that tend to keep ingenious Men from Dispondency I therefore think fit to Inculcate because the Common-wealth of Learning would lose too many useful Observations and Experiments and the History of Nature would make too slow a Progress if it were presum'd that none but Geometers and Mechanitians should imploy themselves about writing any part of that History But to return to those Trials of our own that occasioned this as I hope Seasonable Digression I was about to add That as the acknowledgement I was making that some of the Trials were 〈◊〉 want of Accommodations less Artificial then I could have design'd or wish'd them touches not all nor haply the greatest part of the following Experiments so it need not derogate from the Readers reliance on those which it does concern For though some of them might have been more Artificially performed to the manner yet they could not have been more Faithfully registred as to the Events Which though I dare promise my self that most Readers will be induc'd to believe upon the Considerations not long since intimated Yet I think it requisite to give this intimation on this occasion because that though I have 〈◊〉 largely manifested to what contingencies divers Experiments are liable yet I have found very few whose events are so subject to be varied by slight and not easily beeded circumstances as several Experiments concerning Cold Where oftentimes the degree of that Quality or the time during which it continues appli'd or the manner of Application or the thickness shape and bulk c. of the vessels that contained the matter expos'd to it may have a far greater influence on the success then those that have not tri'd can easily imagine And it increases the difficulty that these Experiments of ours being very few excepted the only that are yet made publick concerning Cold we cannot so easily as in other cases free our selves from the doubts that may be suggested by different events by comparing together several Experiments of the same kind though to obviate this inconvenience as far as I may I have divers times in cases where the Experiments seem'd like to be thought strange or to be distrusted set down several Trials of the same thing that they might mutually support and confirm one another Of those Contingent Experiments about Cold I was newly speaking of the Reader may meet with an eminent Example in the 21. Title where mention is made of the differing Effects of Air blown out of a pair Bellows upon a Weather-glass and as for the suspition I there conclude with though I yet doubt whether 〈◊〉 will reach All the Cases incident to that Experiment I have since been confirm'd in it by finding that by purposely varying the temper of the Bellows themselves I could divers times considerably vary the operations which the Winds blown out of them in their differing states had upon the Liquor in the Weather-glass Of this I expect to have an opportunity of saying more and therefore shall at present add but this one particular which may sufficiently justifie me for having said That Weather-glasses our Sensories may give very differing Informations about the Temperature of the Air turn'd into Wind by being blown out of the same pair of Bellows For having taken two Hermetically seal'd Weather-glasses furnished with highly rectified spirit of Wine and purposely made for my Experiments by a person eminently dexterous in making such Instruments and having likewise provided a large pair of Bellows I found that by blowing 20. blasts at a time on the Ball of one of them though the Pipe were not only slender but of an unusual length amounting to about 30. Inches yet the Liquor did not sensibly subside any more then rise And in the other Weather-glass whose Pipe was less long but whose Ball was purposely made far greater to be the fitter for short and nice Experiments we found more then once and that as well in the cold Air as in a close Room that the wind that was blown in divers blasts out of the Bellows against the lower part of the Instrument did not only make the spirit of Wine subside but did make it manifestly though but very little ascend And 't is not necessary for the making good of what I taught that such Trials should always succeed just as these did since it may suffice to prove what I pretended that a good seal'd Weather-glass did divers times discover the Wind to be rather warm then cold when upon Trial then purposely made it felt not only manifestly but considerably cold both to a By-standers Hand and to my own Hand and Face though my hand that was blown upon were immediately before more then ordinarily cold And I shall here add That judging it fit to make further Trial with an unseal'd Weather-glass I made one that was in some regards preferable to those mentioned in the second Praeliminary Discourse by making the Bubble large and the Cylindrical Pipe so proportion'd to it that instead of a Drop of water a Pillar about an Inch long of that Liquor was kept suspended and play'd as well conspicuously as nimbly up and down in the Pipe And having fastned this Instrument in an erected Posture with the Sphaerical part uppermost to the inside of a Window by blowing upon the Ball with the Bellows above mentioned which had lain some hours not very far from the Chimney-corner but without seeming to be sensibly warm'd by the neighbourhood of the fire a very few blasts made the suspended water hastily subside and thereby witness the Expansion and so the warmth of the included Air and upon my ceasing to blow the same water would reascend in the Pipe and that though I stood near it to watch it which shows that the former Depression was not caused by the approach of my warm Body and this I did more then once both alone and before witness notwithstanding that the Air blown at the same time out of the same Bellows upon our hand and face seem'd cool enough But fearing to insist any longer on this matter in a Preface I think it now unseasonable to add That as some contingent Experiments in subsequent Trials may Fail oftner
NEW EXPERIMENTS AND OBSERVATIONS TOUCHING COLD OR AN EXPERIMENTAL HISTORY OF COLD Begun To which are added An Examen of Antiperistasis And An Examen of Mr. Hobs's Doctrine about COLD By the Honorable Robert Boyle Fellow of the ROYAL SOCIETY Whereunto is annexed An Account of Freezing brought in to the Royal Society by the learned Dr. C. Merret a Fellow of it Non fingendum aut excogitandum sed inveniendum quid natura faciat aut ferat Bacon LONDON Printed for John Crook at the Sign of the Ship in St. Pauls Church-yard MDCLXV THE PUBLISHER TO THE INGENIOUS READER I Am fully perswaded you will much rejoyce to see that Exquisite searcher of Nature the Illustrious Robert Boyle come abroad again as knowing he never does so but when richly furnisht with very Instructive and Useful matter He presents you here with a Treatise of New Observations and Experiments in order to an Experimental History of Cold. This is the Body of the Book but it comes accompanied with some Preliminaries and an Appendix whereof the former contains New Thermometrical Experiments and Thoughts the latter an Exercitation about the Doctrine of Antiperistasis followed with a short Examen of Mr. Hobs ' s Doctrine touching Cold. From all which it will more and more become manifest with what spirit and care this Excellent Person advanceth real Philosophy with what exactness he pursueth his Engagement therein and how great caution he useth that nothing may slide into the Philosophical store that may prove prejudicial to the Axioms and Theories hereafter perhaps to be deduc'd from thence Having thus shortly given you my sense of the substance of this Considerable Treatise I am now to advertise you of one or two circumstances necessary to be taken notice of in its perusal One is that the Noble Author being at Oxford when the Book was printed at London he hopes the Reader will not impute to him the Errors of the Press which yet he is perswaded will not be many and out of which must be excepted a Blank or two occasion'd by this That the Authors Papers being near two years since given to be transcribed to one whose skill in writing was much greater than as it afterwards appear'd his knowledge of what was or was not good sense or true English this person suddenly going for Africk before the Transcript had been examin'd and not taking care to leave all the first Copy the Author found besides several Blanks that he filled up out of his Memory or by repeating the Experiments they belonged to one or two where he was not able to repair the Copists omissions And besides unexpectedly met with very many Passages so miserably handled that by putting him to the trouble of writing almost a New Book when part of this was already in the Press it much retarded the Publication of that which now comes forth The other is That whereas in the Preface some passages are so penned as to suppose the Book to be published early in the Winter the Reader is to be advertis'd That the 〈◊〉 part of the Preface was sent a good while since to the Press though the latter however then written out was hindred from accompanying it by some hopes of the Authors to gain by delay an opportunity he missed of to perfect an Experiment he was desirous to insert and that when the Frost began which was late in the season the Coldness did within a while arrive at that degree that by its operation upon the moisten'd paper it long put a stop to the Proceedings of the Press But the Author that he might neither be quite defeated of his aim nor disappoint the Curious of their Expectation did in the first or second week of the Frost which was about the end of the year 1664. present the Royal Society with divers Copies of the History of Cold though the Book were not then quite printed off And these Books being so near finish'd that of 21. Sections whereof the History of Cold consists the Press had then reach'd to about the 19. and I had the 20. in my hands to supply it when the weather should permit the Author hop'd that by seasonably communicating so much of his intended Treatise to so many of the Virtuosi that were the likeliest to make use of it he had pretty well provided against the Prejudice that might otherwise accrue from the slowness of the Press and therefore allow'd himself to subjoyn to the History the discourse of Antiperistasis and the Examen of Mr. Hobs's Doctrine as belonging to the same subject And finding the frosty weather to continue later than was expected which had he foreseen before his History was printed off it would have given him opportunity of Enlargements he hopes the Publication may not be yet too late for diligent Readers to make some use of the season for examining his Experiments or trying some of the New ones those may suggest And therefore for the quicker dispatch of the Book he purposely omits and reserves for another occasion besides the papers that he hath not yet given me some that I have already in my hands And 't is I presume for the same reason that he forbears to publish what he long since writ about the Origine of Forms and Qualities in a small Tract which he had thoughts of sending forth in the company of the ensuing History as a Discourse fit to be an Introduction as well to That as to his Historical writings about Colours and some other Qualities This is all the Advertisement I had to give you And seeing it would be altogether impertinent for me to take any pains or to use any Art to procure a Gust for a Book composed by Mr. Boyle I have no more to say but that the Author being so Generous as to oblige Forrain Nations as well as his Own has already taken care of having it put into Latine Farewel H. O. London March 10. 1664 5 THE AUTHORS PREFACE INTRODUCTORY COld is so barren a subject and affords so few Experiments that are either very delightful for their surprizing prettiness or very considerable for their immediate use that instead of admiring that any of my friends should wonder at my having been induc'd to write of such a Theme I freely confess that I have been sometimes tempted to wonder at it my self and therefore I think my self oblig'd to give my Readers an account of these three things Why I thought fit to write of Cold at all For what Reasons I have treated of it after the manner to be met with in the ensuing Book And Why I venture my unfinished Collections about it abroad so soon I. To satisfie the first of these Queries I have several things to say And first That the subject I have chosen is very noble and important for since Heat has so general an Interest in the Productions of Natures Phaenomena that Motion excepted of which it is a kind there is scarce any thing in Nature whose
I am now upon for whilest I was yesterday writing It I had occasion to Examine by such a Seal'd Weather-glass as I have been speaking of the Temper of a certain strange kind of mixture that towards the close of this Treatise I shall have Occasion to take special Notice of and though to the touch it appear'd but Lukewarm yet having put into it the Ball and part of the stem of the seal'd Weather-glass I found the Included Liquor slowly enough impell'd up so high that at length to my wonder it rose eight or nine Inches in a Stem which was not much above a foot long but that which I relate as the surprizing Circumstance is that when I had taken out the Thermoscope and remov'd it again into a deep Glass full of Cold water whence I had just before taken it out to put it into the Anomalous mixture I had a mind to examine the Tincture in the Weather-glass did not as it was wont and as any one would have expected begin to subside again towards its former station but continued within about half an Inch or less of the very Top of the Instrument though neither my own busie Eyes nor those of a person very well Vers'd in making and using Thermoscopes could perceive that the expanded Tincture was any where discontinued by any Air or Bubbles which at first we suspected might possibly though it were very unlikely have been generated by the Tepor of the mixture But that which continued our wonder if not increased it was that during four or five hours that the Instrument continued in the Cold water and during some hours also that it was expos'd to the Air the Tincture did not subside above half an Inch and which is yet more strange having left the Glass all night in the window of a Room where there was no Chimney I found in the morning that its descent was scarce sensibly greater for it continued about eight Inches higher then the mark it stood at when I first put it into the Lukewarm mixture and how long it will yet retain this strange expansion is more then I can tell But by this and what I may have occasion hereafter to relate concerning this mixture it may appear somewhat the more reasonable to suspect that even seal'd Weather-glasses furnished with high rectifi'd spirit of Wine may in some though very rare conjunctures of Circumstances and from some peculiar Agents either by their insinuating themselves through the Pores of the Glass or on some other Account receive impressions that as far as can easily be discern'd are not purely the genuine and wonted Operations of Heat and Cold. The Chymist Orthelius tells us that the Liquor distill'd from the Oar of Magnesia or Bismute which seems to be the same Mineral that we in English call Tin-glass will swell in the Glass 't is kept in not only manifestly but very considerably at the full Moon and shrink at the new Moon and if all my endeavours to procure that Oar had not prov'd fruitless I should be able by my own Experience to disprove or confirm so admirable a Phaenomenon but being as yet unfurnish'd to make the Trial my self lest it might appear a Vanity so much as to mention without rejecting it a thing so very unlikely I shall add that since I find the Thing for the main which was delivered by the Chymist imploy'd as an Argument by a famous Mathematician the Jesuite Casatus whose expressions are such as if he himself had observ'd that even in stopt Glasses the foremention'd Mineral spirit increased very sensibly in Bulk about the time of the full Moon which wonder being admitted may not only countenance what we were saying but hint some other very strange things in Nature This brings into my mind what I have elsewhere mention'd that a Tincture of Amber I had made with high rectifi'd spirit of Wine did for many Moneths in a well stopt Glass discover it self to be affected with certain changes which were thought to proceed from some secret mutations of the Air that did sensibly so work as I had not observed it to do upon other Liquors wherein the spirit of Wine abounded And perhaps upon long and diligent observation one might find a Disparity betwixt Weather-glasses kept in the same place but furnished with differing Liquors a Disparity I say that could not be so well ascrib'd to any thing as to the peculiar Nature of the Respective Liquors which though of divers kinds may to add that towards the facilitation of Trials be made of a very conspicuous colour by the self-same Metal Copper which not only gives the Known colour in Aqua fortis but affords a fair solution in Aqua Regis and it makes a Liquor of a most deep and lovely blew in spirit of Urine or of Sal Armoniack and the like nay I have found that in good Chymical Oyl of Turpentine for express'd oyls are too easily congeal'd the bare filings of it will yield a sufficient Tincture But because it is yet but a bare suspicion that Seal'd Weather-glasses made of differing Liquors but in other points alike may be otherwise then uniformly affected by the Temperature of the External Air I shall now add an observation already made to show that even the Seal'd Weather-glasses furnish'd with spirit of Wine are not so perfectly secluded from all commerce with external Bodies and liableness to their operations but that they may be wrought upon otherwise then we think For I have more then once observ'd that even in seal'd Thermoscopes made purposely at home for me and with great care by the expertest maker of Them after a good while and when no such matter was expected there have emerg'd Bubbles which whether they proceeded from some undiscernable Particles of Air harbour'd in the Pores of the Water which in process of time by their Union came to make conspicuous Bubbles or from some dispos'd particles of the spirit of Wine it self by successive alterations brought to a state of Elasticity I now examine not but only affirm that sometimes I have had of these Bubbles great enough to possess the space of many Inches in the shank of a long seal'd Weather-glass and I have been troubled with them in more Weather-glasses then one or two which I therefore take Notice of not only because it serves to prove what I was saying but because it is very fit an Advertisement should be given of it to prevent mistakes For when these Bubbles are small and are generated or happen to stay at or about the Place where the Sphaerical and Cylindrical parts of the Glass meet they may easily as I have observ'd lurk unheeded and reaching from side to side so divide the spirit of Wine in the Ball from That in the Stem that the latter shall not be able 〈◊〉 rise and fall according to the changes of the weather the Bubble notwithstanding its aerial nature being more indispos'd to be mov'd up and
through the sides of the glass but that the Air within the vial highly refrigerated by the mixture Did upon the account of their free intercourse enable the Air contiguous to the outside of the vial to freez the Dew it met with sticking on it we prosecuted the Experiments with the addition of this circumstance that on several occasions we seal'd up the vial that contained the 〈◊〉 and the other frigorifick body it was mixt with and afterwards by the help of this mixture froze the externally adhering moisture 8. Having then according to this way substituted spirit of Nitre for oyl of Vitriol or spirit of Salt we found that it froze yet more powerfully then either of those two liquors and continued to do so in those parts of the outsides of the glass that were adjacent to the included snow till that snow was almost totally resolv'd into a liquor This we tri'd both in a thin seal'd glass and in a pretty thick glass stopp'd only with a Cork 9. Afterwards we successfully enough tri'd the Experiment with spirits less acid as not only with spirit of Vinegre but with spirit of Sugar I mean the Red Empyreumatical spirit forc'd over in a Retort which mixt with snow according to the manner of the Experiment did at length freez the externally adhering moisture But the filmes of ice were very thin and very apt quickly to disappear 10. Having thus made a number of trials with acid spirits we thought fit to make some with Urinous spirits that abound in volatile salt and accordingly having mixt spirit of Urine and Snow in an open vial and agitated them we found that the external moisture did discernably though not very strongly freez But with spirit of Sal Armoniack drawn from Quick Lime according to the way I have delivered in another Treatise the operation was quick and powerful enough 11. Having tri'd to freez water with acid and with volatile spirits 〈◊〉 we thought it not amiss to try what they would do both together and accordingly pouring upon snow both some spirit of Urine and a little oyl of Vitriol and shaking them into the snow in an open Vial we found that the mixture did freez though the glaciation in this case produced were very languid 12. Having thus tri'd salts disingag'd from their grosser parts or shattered into Corpuscles by distillation we made some trial likewise with grosser salts as with Sal Gem with a sublimate made with common Sublimate and Sal Armoniack nay and with both 〈◊〉 and Kitchin Sugar with all which among 〈◊〉 like bodies that I can now Remember the Experiment succeeded well enough also a very strong solution of Pot-ashes mixt with snow in a open single Vial did freez but that very faintly And both a very strong solution of very pure salt of Tartar and at another time a strong solution of Pot-ashes being the one as well as the other mixt and agitated with snow in a single vial produced filmes of ice though thin ones on the outside of the glass 13. After this we thought fit to make a trial of another kind of which I find this account among my Notes We filled a single vial with snow and then powred into it a convenient proportion of a strongly sweet solution of minium in spirit of Vinegre and having shak'd the mixture together we found that this sweet Sugar of Lead did as well as acid and alcalizate salts excite the cold of the snow so much as to produce filmes of ice on the outside of the glass but a parcel of the same solution being for divers hours kept in snow and salt was not thereby frozen In order to the discovery of some hints of the account upon which the above mentioned mixtures were more intensly frigefactive then snow alone we sealed up a single vial full of snow unmingled with any other ingredient and found it to thaw much more slowly then any of those parcels of snow which we had mixt with salts or spirits In prosecution of this conjecture we shall add that for ought we could find by divers trials no salt that helps not the snow to dissolve faster then else it would did inable it to produce ice though usually it did produce dew on the outside of the vial that contained the mixture and accordingly neither Chrystals of Tartar nor Borax both beaten to powder nor which is more considering what we lately noted of the effects of another sort of Sublimate would Sublimate inable the snow to freez as well the powder of Sublimate as that of Borax and that of Tartar lying for a great while in the snow undissolv'd 14. Belonging to this matter I find among my papers also this Note Water of Quick Lime made by quenching store of unslak'd Lime in common water twice tri'd would not make snow freez perhaps because though the water were kept stopt yet the liquor having been kept in the glass a twelve-moneth and more probably the spirits may have flown away which I find by inquiring of one that Drinks much Lime-water that it abounds with when fresh and grows destitute of a while after and possibly also the badness of the Lime was the cause why being mingled with snow it would not freez though all the vials that did not freez did yet gather store of dew on the outsides perhaps because of the snow whose melting alone may suffice to produce that effect 15. It may seem somewhat more strange that distilled oyl of Turpentine which is so hot and fiery a liquor should not enable snow to freez but this agrees not ill with the conjecture lately mentioned for it will hereafter appear that in oyl of Turpentine Ice dissolves slower then in Divers other liquors without excepting common water it self 16. And yet notwithstanding the bad success of this trial we were not Discouraged from making another with spirit of Wine for though according to the common opinion of Chymists and Physicians it be a mere vegetable Sulphur yet we that have elsewhere ventured to ascribe some such operations to it as Chymists would have belong to Saline Liquors did not scruple to seal up in a single vial almost filled with snow a convenient quantity of pure spirit of Wine drawn off from quick Lime the better to dephlegm it and of this mixture we found the operation more powerful then any of those we have formerly mentioned for the freezing vertue of this did not only last long both in the seal'd single vial and in another that was open but the inclosed mixture presently crusted the outside of the glass or of the neck if it were made to fill that with ice which might be taken off in flakes of good breadth or in pieces of good thickness Nay it presently froze Urine into Figured ice which might be taken off in scales 17. This last circumstance puts me in mind of another Experiment whereby we tried by a vigorous mixture of Snow and some choice spirit of Nitre we had met with
to freez liquors of more difficult conglaciation then fair water We took then some snow and mingled with it some of the newly mentioned spirit of Nitre in so luckly a proportion that it froze very vigorously and very suddenly insomuch that once almost as soon as it was set to the ground it froze the vial to the floor it was set on and the outside of the glass that contained this mixture we wetted with spirit of Vinegre which was frozen into pretty thick ice But yet not quite to forget that circumstance retaining the salt taste of spirit of Vinegre and though this mixture would not discernably freez spirit of Nitre on the outside yet it transmitted cold enough to freez weak spirit of Salt and to give Us the pleasure of seeing some Saline liquors presently turned into figur'd Ice as not only the last mentioned spirit exhibited some little as it were Saline Iceikles crossing each other and quickly vanishing but which was far prettier having often observed that Sal Armoniack being dissolved in water and the solution being put very slowly to evaporate in part but not too much away the remaining liquor would in the cold shoot into parcels ofsalt very prettily figur'd some of them resembling combs with teeth on both sides and others resembling feathers having observ'd this I say and being desirous to try whether the spirit of Sal Armoniack distilled by the help of quick Lime being put to congeal on the outside of a glass would not afford a Resemblingly figured Ice we found upon trial both that the mixture was able to freez that subtile spirit and also that it shot into Branches almost like those exhibited by such salts undistilled And it was not unpleasant to behold how upon the inclining the glass so that the freezing mixture rested a little near any part of the spirit this liquor would shoot into such branches as we have been speaking of so nimbly that the eye could plainly discern them as it were to grow and hastily overspread the surface of the glass but those Branches were wont quickly to vanish I had almost forgot to mention that I tried the freezing with snow and divers fermented Liquors undistilled instead of spirit of Wine and though the Experiments succeeded not with small Beer much less with water yet there was a glaciation though but slight produc'd not only by the addition of Wine but even by that of moderately strong Ale 18. Having observed that the Liquors and other bodies that assisted the snow to freez were generally such as hastned its dissolution we thought it not altogether unworthy the trial to examine what would be the Event of procuring a speedy dissolution of the snow by substituting bodies actually warm instead of potential hot ones Of this sort of trials I find among my Notes these two registred 1. Into a single vial almost filled with snow there was poured a pretty quantity of well heated sand that it might dissolve the snow in many places at once without heating the ambient Air or the outside of the glass but though the solution of the snow seemed to succeed well enough upon the shaking of the vessel yet the outside of the glass was only bedewed not frozen 2. Into another single vial almost filled with snow we poured some water which we judg'd of a convenient warmth and we poured it in by a funnel that had but a slender orifice beneath that the warm water might fall into the middle of the snow without Running to the sides and taking a convenient time to shake the glass we did by this way produce a very considerable degree of cold and much dew on the outside but were not satisfied that any of that dew was frozen though the success would have invited us to have made further trials in greater glasses if we had had any more snow at hand Wherefore This Experiment is to be further and more artificially tri'd 19. It is a common tradition not only among the vulgar but I presume upon their account among learned men that the oftentimes variously and sometimes prettily enough figur'd hoar frost which is wont to appear upon glass windows in mornings preceded by frosty nights are exsudations as it were that penetrating the glass-windows are upon their coming forth to the cold external Air frozen thereby into variously figured ice How groundless this conceipt is may be easily discovered if men had not so lazy a curiosity as not to try which they may do in a moment and without trouble whether the Ice be according to the tradition on the outside of the window and not contrary to it on the In-side where indeed it is generated of the aqueous Corpuscles that swiming up and down in the Air within the Room are by the various motion that belongs to the parts of fluid bodies as such brought to pass along the window and there by the vehement cold of the neighbouring external Air communicated through the glass condens'd into dew and frozen into Ice 20. And because divers modern Naturalists have taught I think erroneously that glass is easily enough pervious not only to Air but to divers subtile liquors lest the favourers of this Doctrine should object that we have ill assigned the natural cause of the ice appearing on the outside of the glass in the former Experiments which according to them may rather proceed from the subtler but yet visible parts of the excessively cold mixture of the snow and saline bodies penetrating the pores of the glass and setling on the outside of it To obviate this objection I say and to confirm what we have taught in another Treatise about the wandring of store of aqueous vapours through the Air we will add the following Experiments purposely made to evince these truths 21. At one time four ounces and a quarter of a mixture of Ice and Salt being inclosed in a vial and thereby enabled to condense the vapours of the ambient Air was by their accession increas'd 12. grains Another time a vial wherein snow weighing two ounces six drachms and an half was suffered to condense the vapid Air the dew that partly adher'd to it and partly fell from it made the whole weigh four grains more then the vial did when it was first put into the scale in which scale we found some water flowing from the dew which gave that increase of weight And here let me add by the way that the tip of This seal'd vial being broken under water suck'd in a considerable quantity of it whether because of some little rarefaction of the Air included in the sealing or because of the infrigidation of that Air by the snow or for both these Reasons or any other I shall not Now dispute 22. But other Experiments to the same purpose we made wherein the increase of weight was more considerable and that the way we used may be the better understood and the conclusion built upon it the more undiscuss'd we will add a couple
in 〈◊〉 He answered me That it did there freez much harder then in our Climate but would not that 〈◊〉 had observed be turn'd into true perfect Ice On the other hand I find the Testimony of that Ingenious Navigator Captain T. James who relating the effects of cold he met with in the Island where he and his men were forc'd to winter does in one place reckon Oyl among the Liquors such as Vinegre and Sack that ev'n in their house was firmly frozen and more expresly elsewhere All our Sack says he Vinegre Oyl and every thing else that was liquid was now frozen as hard as a piece of wood and we must cut it with a Hatchet And Olaus Magnus speaking of the fights wont to be made upon the Ice in the Nothern Regions Glacialis Congressus says he fit in Laneis Calcibus non pellibus aut Coriis unctis 〈◊〉 enim frigoris quodcunque sit unctuosum convertit in Lubricitatem glacialem There being a great Similitude in point of Inflammability and disposition to mix with many subtle Oleous Bodies betwixt spirit of Wine and Oyl and as great an affinity in divers other regards betwixt that spirit and both aqueous and saline Liquors with which it will readily mix I had a great Curiosity to know what kind of change would be produc'd in vinous spirits in case they were exposed to a cold great enough to work a visible change in their Texture I therefore solicitously inquir'd of the Russian Emperors lately mention'd Physician whether or no he had observ'd in Muscovy any manifest change produc'd by cold in Hot Waters and spirit of Wine To which he returned me this answer That common Aniseed-water and the like weak spirits would be turn'd into an imperfect kind of Ice and that ev'n the very strong spirits though they would not be turn'd into Ice would be turn'd into a kind of substance like Oyl Title III. Experiments touching Bodies Indispos'd to be Frozen 1. WE found many liquors whose subtle parts being by Distillation brought over and united into very spirituous liquors and so either totally or in great measure freed from those phlegmatickor aqueous parts that dispose Bodies to congelation could not be brought to freeze either by the cold of the external Air to which in frosty nights we exposed them or by such an Application of snow and salt as served to freez other Bodies 2. Of this sort were among acid menstruum's Aqua fortis spirit of Nitre of Salt also oyl of Turpentine and almost all I add the word almost because the Essential oyl of Aniseeds and the Empireumatical oyl of common oyl will lose their fluidity in a less degree of Cold then that of our mildest frosts I say almost all the Chymical oyls we had by us as likewise spirit of Wine and other strong spirits of fermented Liquors and even 〈◊〉 it self if it were good would very hardly be brought to afford us any Ice at all But among the many liquors that would not freez there were a few whose trials afforded us some circumstances not altogether unworthy their being mention'd As 1. I being desirous to satisfie some friends that 't was the brisk spirit of the Grapes whether resulting from or extricated and exalted by fermentation that kept all the rest of the Sack from freezing I took a parcel of that liquor that would afford us no Ice at all and by the help of a lighted candle or some other actually flaming body kindled it and letting the inflammable part burn away the remaining part of the Liquor which was by vast odds the greatest part was easily brought to freez Next when the formerly mentioned trial was made with water and Pot-ashes we likewise in another glass exposed a solution wherein the proportion of salt of 〈◊〉 in reference to the water was four times greater there being in this zij of the salt to 〈◊〉 only of water and this solution though the glass were covered with hoar frost and Ice on the outside froze not at all within And likewise when another time we made a very strong solution of salt of Tartar that was very pure and fiery it did not freez though a considerably strong solution of salt of Pot-ashes that was exposed with it did So that these Experiments about the glaciation of Lixiviate Liquors must be repeated to be reduc'd to a certainty 3. That the common express'd oyls of Vegetables will after their manner freez that is lose their fluidity and become as it were curdl'd in very cold weather is a 〈◊〉 of common observation but I had a mind to try whether or no Train oyl that is made of the fat of Animals commonly that of Whales though not by distillation properly so called yet by the help of fire would not be more capable of resisting the violence of the cold and accordingly I found that Train oyl exposed to the Air in a convenient vial continued fluid notwithstanding a more then ordinary sharpness of weather and this I tried two or three several times but at length one night proved so very cold that the next morning I found the oyl unfluid which differing 〈◊〉 seem a little to Countenance but more to disfavour the Report of Olaus Magnus who writes That whereas in Northern Regions 't is usual for strong places to lose in winter the protection afforded them in Summer by their Ditches though never so wide and deep because the frost makes them easily passable to the Enemy This inconvenicy is wont to be prevented by pouring into the Ditches the Ice if there be need being first broken great store of this Train oyl which swimming upon the surface of the water and being incongealable by the cold protects the subjacent water from the freezing violence of the cold and keeps the moats unpassable But because our Author mentions this as a known and vulgar Practice in those Icy Regions it may perhaps deserve a little Enquiry whether the Whale Oyl used by the Swedes Laplanders Muscovites and other Inhabitants of those parts be not differing either as to the Fishes 't is made of or as to the way of making it or as to the way of keeping it from such Train Oyl as we Employed unless perhaps it do already appear by the Relation of writers belonging to those Countries or of Travellers that have been in them that Olaus Magnus has in that particular as I fear he has in some others misinformed his Readers 4. We took notice that a strong solution of common Sugar was easily enough turned into Ice but on a strong solution of Sugar of Lead we could not with salt and snow work the like change and this though the trial were not negligently made which I therefore think not unworthy to be mention'd because that the two only Ingredients of this Sugar were Lead which is esteemed a very cold Body and spirit of Vinegre from which as I noted above we did by the like degree of cold
water we would easily be more certain of then if we had imploy'd spirit of Wine and this oyl it self we rectifi'd in a gentle heat to make it the more pure and subtle Then we took a small round vessel of clear glass furnish'd with a conveniently long stem or pipe and having first weighed the glass alone in a pair of very good scales we found it to weigh 〈◊〉 〈◊〉 56 ½ gr then putting in oyl of Turpentine till it fill'd the round part of the Glass and ascended a little way into the stem we carefully mark'd with a Diamond on the outside of the Glass how high it reach'd and then weigh'd the Glass and the Oyl together which weigh'd 〈◊〉 〈◊〉 and 34 ½ gr then we put in by degrees a quarter of a Drachm and with a Diamond carefully mark'd how high it reach'd in the pipe and so we continued putting in several Quantities of oyl still carefully weighing each parcel in the scale and marking its height on the outside of the Glass which we did in order to a certain design and found it a work tedious and troublesome enough till the Liquor and the Glass together weighed 〈◊〉 〈◊〉 4 ½ grains then we put fair water into an open-mouth'd Glass in which we also plac'd the little Bolt-head with oyl of Turpentine and by such a circumposition of salt and snow as is hereafter to be often mention'd we made the water which was contain'd in the wide mouth'd Glasses and by which the Sphaerical part of the Bolt-head containing the Oyl was surrounded we made this water I say begin to freez and when we perceiv'd a little Ice to be produc'd in it we carefully mark'd with a Diamond to what part of the stem the oyl of Turpentine was subsided and then transferring the Bolt-head into a mixture of snow and salt where we kept it for an hour or two till we could perceive it to fall no lower and marking with a Diamond this station also of the Liquor we afterwards remov'd the Glass into a warmer Air till the Oyl by expanding it self had regain'd the highest mark whence it had begun to sink Then into a very little Glass carefully counterpois'd in a pair of exacter scales then the former we gently poured out of the Oyl till what remain'd rested against that mark on the outside of the stem to which it fell when the water began to freez and this we found to amount to somewhat above 9 ½ grains so that for conveniency of reckoning we may safely enough take the Intire number of 10. grains After this we poured out of the remaining oyl into the same little Glass till what rested in the Pipe was even with that mark to which the snow and salt had made it fall and this parcel of oyl hapned to be almost precisely of the same weight with the other so that in this Trial for perhaps in others which it were therefore worth while to make the degree of Cold may much vary the Events the Artificial way of freezing we imploy'd made the oyl subside as much after it had been refrigerated and condens'd by a cold capable of freezing water as that degree of Cold had been able to condense it at first And lastly having deducted the weight of the Glass from the weight of the whole Oyl and Glass to obtain the weight of the oyl alone and having divided the weight of the whole Oyl first by that of the former parcel we have mentioned to be ten grains and then by the superadded weight of the second parcel we took out both which parcels together we estimated at twenty grains we found that rectifi'd oyl of Turpentine of a moderate temper being expos'd to such a degree of Cold as would freez common water did by by shrinking lose but about a ninty fourth part of its Bulk and being reduc'd to as great a degree of Cold as we could bring it to by snow and salt ev'n then it lost but about a forty seventh part of its Bulk I say about because I thought it needless as well as tedious to mind fractions and little odd numbers especially since as we formerly intimated it was scarce possible to arrive at a great exactness in such a Neck as that of our Bolt-head though it were proportionable enough to the Ball and chosen among several that were purposely procur'd for the trying of Experiments 8. There are some other Trials about the Degrees of Cold which for want of Ice and other Accommodations we could not make as we would have done often nor shall scarce be able to do it till more friendly Circumstances afford us an opportunity And yet because our Trials though not prosecuted as far as we thought may possibly prove not unwelcome we will subjoyn something about two of the chiefest of them 9. The one was design'd to measure in what proportion water of a moderate degree of Coldness would be made to shrink by the circumposition of snow and salt before it begin by Congelation to expand it self of this what we shall here take notice is only That by a Trial purposely made with common water in a round Glass furnish'd with a long stem we found the water in that stem to subside so very little that whether or no it were insensible it was inconsiderable But probably a greater Quantity of water and a slenderer stem would have made the shrinking of the Liquor more Notable and upon that Account 't is that I here mention It. 10. The other Thing was to measure by the differing weight and Density of the same portion of water what change was produc'd in it betwixt the hottest time of Summer and first a glaciating Degree of Cold and then the highest we could produce by Art And in order to this we weigh'd with a pair of exact scales a glass bubble heavier then water in that liquor when it seemed to be at a moderate Temper as to Coldness and by the Diminution which we found of the glasses weight in the water we easily collected according to the Rules of the Hydrostaticks the weight of as much water as is equal in bulk to the glass Bubble and thereby the Proportion betwixt the glass and an equal bulk of such water as we first weighed it in then by the application of snow and salt we made that water begin to freez and weighing in it again the same bubble 't was easie to collect by the Decrement of its weight in this refrigerated water what Proportion an equal Bulk of the liquor did then bear to the Glass and by comparing these two differing Proportions together we were assisted to make an Estimate how much the water was made more heavy and dense by the Action of a freezing degree of Cold Afterwards taking our time in Summer we thought fit in the same parcel of water that had been purposely reserved in a glass to weigh the same bubble that by the difference of its weight in the water when
as it could to its temper and consequently to the same temper as to heat and cold and then with the warmth of ones hand the included ice being loosened from the glass as it was taken out and a ruler divided into inches and eights being laid alongst it with a knife a little warmed the ice was soon and yet not carelesly divided into several small Cylinders of three quarters of an inch a piece and these Cylinders thus reduced to as sensible an equality as we could were nimbly and carefully put into the several liquors hereafter to be mentioned and whilest we our selves watched very attentively till each of these icy Cylinders was quite and yet but just dissolved we caused others to keep time by the help of a Pendulum whose Vibrations were each a second minute or 60. part of a Common Minute whereof 60. go to make an hour and it was easie for those we appointed to watch the Vibrations of the Pendulum notwithstanding the Quickness of its Motion because it was fitted to a little Instrument purposely contrived for such nice observations wherein a long Index moving upon a divided Dyal plate did very manifestly point out the number of the Diadromes made by the Pendulum 3. This Experiment was afterwards repeated twice with Cylinders of ice each of them an inch long and though the successes of these trials were various enough yet we shall subjoyn both the last as being made with more advantage then the first that the more light may be gathered from them and that at least we may discover how difficult it is to make such Experiments in this matter as that all the nice circumstances of them may safely be relied on I. Trial. 1. Oyl of Vitriol where a Cylinder of Ice of an iuch long being put into lasted 5. minutes 2. Spirit of Wine in which the ice sunk lasted 12. minutes 3. Aqua fortis lasted 12 ½ minutes 4. Water lasted about 12. minutes 5. Oyl of Turpentine lasted not good 44. minutes 6. Air lasted 64. minutes II. Trial. 1. In Oyl of Vitriol where an inch of Cylindrical ice lasted 3. minutes 2. In Spirit of Wine lasted 13. minutes 3. In Water lasted 26. minutes 4. In Oyl of Turpentine lasted 47. minutes 5. In Sallet Oyl lasted 52. minutes 6. In the Air lasted 152. minutes 4. We likewise thought it worth trying whether there would be any difference and how much difference there would be in the Duration of pieces of ice of the same bulk and figure some of them made of common water and others of frozen Wine Milk Oyl Urine and other spirituous liquors these several pieces being exposed to be thaw'd in the same Air or other ambient liquor 5. We also tried whether Motion would impart a heat to ice by nimbly rubbing a strong piece of ice upon a plate of ice and though this seemed to hasten the dissolution in that part of the icy plate where the Altrition had been made yet we were unwilling to determine the matter till further and exacter trial have been made 6. And this brings into my mind an Experiment that has by some been thought very strange The occasion I remember was that I received the last Winter the honour of a visit from a Nobleman of great eminency and learning who chancing to come in while I was making some trials with ice would needs know what I was doing with it but the presence of a very fair Lady in whom Hymen had made him happy and of some other Company of that Sex that he brought along with him inviting me to give him the answer that I thought would be most suited and acceptable to his Company I merrily told him that I was trying how to heat a Cold liquor with ice and to satisfie him that was no impossibility I held out an open mouth'd glass full of a certain liquor which for some just reasons I do not describe but do plainly teach it in an opportuner place and desired them to feel whether it were not actually Cold and when they were satisfied it was so I chose among the pieces ofice that lay by me that I judg'd by the eye to be fit for my purpose for every piece was not so for a reason I elsewhere shew and throwing it into this liquor it did not only in a trice vanish in it but the Lady I was mentioning seeing the liquor smoak and advancing hastily to try whether it were really warm found it so hot that she was quickly fain to let it alone and had almost burnt her tender hand with which she had in spight of my 〈◊〉 wasion taken hold of the glass which Her Lord himself could 〈◊〉 indure to hold in his But this Experiment which for the main I have repeated before competent witnesses though it be not impertinent to the History of Cold yet I shall not build much upon it because how strange soever many have been pleased to think it I shall elsewhere shew that I made use of a certain unperceivable slight which in my opinion did as well as the nature of the liquor and the texture of the ice contribute to the suddenness and surprizingness of the Effect 7. But to return to the duration of the effects of Cold I think those much mistaken who imagine that the effects of Cold do continually depend upon the actual presence and influence of the manifest efficients as the light of the Air depends upon the Sun or Fire or other luminous body upon whose removal it immediately ceases For when cold agents have actually brought a disposed subject to a state of congelation though the manifest efficient cause cease from acting or perhaps from being the effect may yet continue For in most cases if a certain texture be once produced in a body it is agreeable to the constancy of nature that it persevere in that state till it be forceably put out of it by some agent capable to overpower it and though we usually see ice and snow as it were of their own accord to melt away when the frosty constitution of the Air ceases yet the cause of that may be not barely the cessation of frosty weather but that those easily dissoluble bodies are exposed to the free Air which being heated by the Sun beams and perhaps by calorifick expirations from the earth is furnisht with an actual cause upon whose account it destroys the texture of the ice and snow but even here above ground if snow be well compacted into great masses in which by reason of the closeness of the little icickles but little Air is allowed to get between them I have seen such masses of snow last so long not only in thawing but in rainy weather as to be wondered at and if such snow or ice be kept in a place where it may be fenced from the Sun and other external enimies though the place it is lodged in be not any thing near cold enough to produce ice yet it will as some trial
one fill'd up after the same manner to make the Experiment the more satisfactory But though he could not procure it yet the success was not unwelcome because it was manifest that there were cracks in the Iron in one place conspicuous and in others easily discoverable by blowing into the barrel and putting on the outside of the suspected parts either spittle or some fit liquor whose agitation plainly disclos'd the egress of the wind and there appear'd small cause to doubt but that these cracks were produc'd by the operation of the cold since not only the Smith was a skilful man in his trade and one that I us'd to imploy about Instruments and also the barrel had been sometimes kept many hours fill'd with water without appearing other then very stanch but which is the considerablest circumstance the night before the frost as I lately noted was not able to make the water break out at any of these clefts though it were able to force it self a way out at the screw in spight of all the care we had taken to make it go close I have only this circumstance to add about this matter that when by thawing one part of the ice some pieces of the rest were got out of the barrel all I took notice of appear'd to be full enough of Bubbles but yet such as seem'd lesser then ordinary whether they were so by chance or were determined to be so by the resistence or compression which the freezing water found upon its endeavouring to expand it self in the barrel Appendix to the XVII Title LOng since the writing of the foregoing Section meeting with a passage in Bartholinus where he vouches Cabaeus for the Experiment of congealing water without limiting it to any season of the year by putting Salt 〈◊〉 into it and shaking it strongly I was thereby confirmed that I was not mistaken in supposing that Gassendus mention'd in the former Section did not exclude that corporal and visible Nitre out of the number of the grand efficients of congelation For Cabaeus having publish'd his comment upon Aristotles Meteors whence this experiment is taken by Bartholinus before Gassendus publisht his Book 't is probable that he as well as others borrowed the Experiment from him and Cabaeus as Bartholinus quotes him prescribes the putting the Salt-petre its self into water which being a while put into a brisk motion will after some agitation not only refrigerate that water but bring it to a true and proper congelation Wherefore suspecting that this relation wherein Bartholinus says he will believe him without an oath may have given rise to the opinions and affirmations of those ingenious writers that have since ascrib'd such wonderful coldness to Nitre and finding in Bartholinus that Cabaeus's proportion betwixt the Nitre and the water was that of 35. to a 100. that is almost as one to three I thought it very well worth while to make Trial of an Experiment which seem'd to me little less unlikely then considerable I took then a pound of good Salt-petre and near 3. pound of common water to observe the more narrowly Cabaeus's proportion these being put into a large new Pipkin were kept constantly and nimbly stirr'd about sometimes by me sometimes by one or other of my Domesticks relieving one another when they were weary but though the mixture was with a kind of broad glass spattle kept in a brisk motion that for the most part was 〈◊〉 the manner of a whirle-pool and sometimes a more confus'd agitation and though we kept it thus stirring for almost an hour and a half till we saw no likelihood of effecting any thing by trying our selves any further yet not only we could not perceive that any Atom of true ice was produc'd whereas according to our Authors we might have expected a true and perfect congelation of all or the greatest part of the water but we did not find that there was so much as any freezing of the vapours on the outside of the vessel and for this reason we thought 〈◊〉 about the same time to try the Experiments by another kind of Agitation and mixing two ounces of Salt-petre with about six of water in a conveniently siz'd vial we did several of us successively vehemently shake the vial too and fro till we were almost tyr'd but neither this way was there produced the least ice within the glass or the least congelation of the vapours of the Air on the outside of it 'T is true that when so great a proportion of Salt-petre began to be dissolv'd in the Pipkin the water had a sensible increase of coldness which afterwards seem'd to diminish when once the Nitre was dissolv'd but not to mention that if I much mistake not we have observ'd the water to be refrigerated when upon the dissolution of common salt multitudes of actually cold and solid Corpuscles came to be every way dispers'd through it this coldness produc'd by the Nitre was very far short of the degree requisite to congelation for to satisfie my self that my sense did not misinform me I took a good seal'd Weather-glass of about ten or twelve inches long and immersing it into the cold mixture of Nitre and Water I observ'd the tincted spirit of Wine in the stem to descend not inconsiderably and when I perceived that degree of cold to have wrought its effect I remov'd the Thermoscope into a vial fill'd with common water about which I had caus'd to be plac'd a mixture of beaten ice and salt to 〈◊〉 the contained water in which the ball of the Instrument being plac'd the spirit of Wine hastily descended two or three inches below that place at which it stood when 't was remov'd out of the Nitrous solution And for further satisfaction removing the Thermoscope once again into that solution the spirit of Wine in the stem was hastily impell'd up as if the bubble had been put into warm water And once more the Weather-glass being remov'd into the formerly mention'd 〈◊〉 water the tincted liquor began to fall down hastily again and within a while subsided almost into the bubble whereupon to avoid injuring the instrument we thought fit to take it out so that upon the whole matter if the learned Cabaeus were not deluded by mistaking some Crystals of Nitre which I have observ'd easily to shoot again in water that has been 〈◊〉 with it for true and proper ice I cannot but wonder at his assertion and must take the liberty to think my self warranted by so many Harmonious Trials as I have found unfavourable to the suppos'd supremeness of Cold in Salt-petre to retain my former opinion about it till more succesful Experiments withdraw me from it 'T is a receiv'd Tradition among the Water-men and many others that the Rivers if not Ponds also are frozen first at the bottom and begin to thaw there But though I find this opinion to be in request not only among English Water-men but among the French too yet I think it
18. Title where I recited the Experiment of the infrigidating Winds I should more expresly have taken notice of this circumstance that to satisfie my self that 't was not the bare Wind as such whose operation upon the Air included in the Ball of a Weather-glass made the liquor to ascend we put a mark upon the height it stood at when we had a pretty while blown upon it and then without removing the Bellows put ice and salt about the Iron pipe of it By which mixture the Air that was afterwards blown through that pipe was so cool'd in its passage as to make the liquor very manifestly to ascend even in a Weather-glass where I did imploy as I have elsewhere declared that I often do Quicksilver instead of water or spirit of Wine And least the vicinity of the frigorifick mixture should be suspected to have caus'd this contraction of the included Air we did sometimes purposely intermit the moving of the Bellows without removing the Weather-glass and though notwithstanding that vicinity the liquor would begin a little to subside yet when ever the cold spirits or the Corpuscles of the highly refrigerated Air were by the playing of the Bellows anew approach'd to or rather brought to touch in swarms the globular part of the instrument the Mercury would manifestly ascend And since we are speaking of Weather-glasses I shall on this occasion subjoyn That certain circumstances may also vary the success of another Experiment somewhat of kin to that lately repeated about the pendulous Drop which is briefly mentioned not far from the beginning of the first Praeliminary Discourse For though the common Thermometers that are here wont to be sold in shops have usually the Pipe of the Bolthead very large in proportion to the Ball and therefore are in that place said to be Weather-glasses not nice and though on such instruments in certain Temperatures of the Air intimated by the word sometimes imploy'd in that passage the Air blown out of a pair of Bellows against some part of the included Air would not especially at the beginning make the Air sensibly contract it self and the liquor ascend though at the very first and second blast the coldness of this artificial Wind might be very sensible to the touch which was the thing intended to be taught in that passage yet having the curiosity with other Bellows at another season of the year to blow long upon the Ball of a not common but nice Weather-glass of my own making furnished with a pipe that was very slender I divers times but not always found the tincted liquor manifestly enough to ascend as if the Wind consisting of a more compress'd Air did by containing a greater number of cold particles in the same room more affect the internal Air then the contact of the calm and lax outward Air did before which disparity of events has given me the design of making further Trials with differing Thermoscopes at other seasons of the year to see if I can bring the matter to some certainty by discovering the cause of this contingency in which I afterwards suspected that some light degree of warmth or coolness in the Bellows themselves which as being unmanifest to the sense scap'd unheeded might have an interest When I was about some of the former Experiments I would willingly have had an opportunity of trying with a good seal'd Weather-glass what difference there would be betwixt the cold of the nocturnal Air in a frosty night in places where the Air was kept calm by being shelter'd from the wind not by inhabited buildings but by some Wall or other body whence any warm Effluviums were least to be expected and betwixt the cold of the same Air in places where cold winds especially Northerly or Easterly did freely and strongly blow But my occasions then confining me to a Town I had not conveniency to make any secure observations of that nature and even in a more commodious place unless it were determined whether there be Corpuscles properly and constantly frigorifick upon whose account some winds are so much colder then others there may arise more scruples about this matter then I must now stay to discuss There is one thing more that it may be is not impertinent to mention before I take leave of the XVIII Title for in confirmation of what is there delivered concerning the Vicissitudes of these troublesome degrees of cold and heat within the the compass of the same Natural day complain'd of by the Patriarch Jacob and by Olearius I shall add that having since had opportunity to inquire about such matters of a learned Physician lately come from the Indies he assur'd me that notwithstanding the violent heats of the day he usually observed the nights to be so very cold that he was perswaded some positively frigorifick steams did in the night ascend out of the Earth and make it very expedient if not necessary for those English that live in the warmer parts of America to imitate the Natives in keeping fires under their Hammacks or hanging Beds I thought it might be a Luciferous Experiment in relation to an Hypothesis that might be propos'd about cold to try whether if two such liquors were provided as by being mix'd together would so far forth lose their fluidity as to obtain at least the consistence of an Unguent this impediment put to the former confused and greater agitation of their parts would produce any sensible degree of cold this I thought fit to try by immersing for a competent time the Ball of a tender seal'd Weather-glass into each of the liquors apart and then into the soft mixture their coalition would compose To produce such a mixture more ways then one it was not difficult for me by the help of some Experiments I had provided to add to my History of fluidity and sirmness But though a strong solution of Minium or calcined Lead in spirit of Vineger or a very strong infusion of good quick-Lime in water will either of them and one of them I did make use of though I have forgotten which coagulate a just proportion of good Sallet Oyl to name no other made by expression into such a consistence as I have been speaking of yet for want of a seal'd Thermoscope tender enough I cannot now repeat the Experiment and till I do I dare not draw any conclusion from it though if I much misremember not when I show'd it an ingenious person neither he nor I could perceive that the liquors by being depriv'd of their fluidity had acquir'd any thing of coldness discoverable by the seal'd Weather-glass It is much controverted among the Curious whether water be capable of Compression and divers have of late inclin'd to the negative upon observing a want of cogency in the Experiments that have been brought to evince the affirmative What Trials and Observations we long since made about this matter may be met with in some of our other Treatises wherefore I shall now subjoyn that
I mean the heating of quick-Lime in cold water I confess I cannot but admire the Laziness and Credulity of Mankind which have so long and generally acquiesc'd in what they might so easily have found to be false This I say because I was possibly the first that has had both the curiosity and boldness to examine so general and constant a Tradition yet I doubt not that you will soon be brought to take it as well as I for as great as popular an error For to let you manifestly see how little the Incalescence of the quick-Lime needs be allowed to proceed from the coldness of the ambient water if instead of cold water you quench it with hot water the Ebullition of the liquor will not only be as great as if the water were cold but oftentimes far greater As I have sometimes for curiosity removed boiling water from the fire and when the liquor had left of boiling but was yet scalding hot I put into it a convenient quantity of quick-Lime and after a while the water which as I said had ceas'd from boiling began to boil afresh with so much vehemence and such large and copious bubbles that it threatned to run over the Pot of which before the effervescence a considerable part was left unfill'd And this was no more then what I might well look for hot water being much fitter then cold to pervade nimbly the body of the Lime and hastily dissolve and set at liberty the igneous and saline parts wherewith it abounds And how much a greater interest salts may have in such incalescencies then Cold I have also taken pleasure to try by pouring Acid spirits and particularly spirit of salt upon good quick-Lime For by this means there would be a far greater degree of heat excited then if I had instead of spirit of Salt used common water And this whether I imploy'd the spirit cold or hot For in either case so small a portion as about the bigness of a Walnut of Lime put into a small glass would by the addition of a little spirit of Salt put to it by degrees both hiss and smoak and boil very surprizingly and notwithstanding the small quantity of the matter would conceive so great a heat that I was not able to hold the glass in my hand And to show some friends how little heat excited in quick-Lime by cold water proceeds barely from the coldness of that liquor I caus'd a parcel of good Lime to be beaten small and putting one part of it into a glass vessel I drench'd it plentifully with oyl of Turpentine more then it would imbibe and the other portion of the Lime I likewise drench'd with common water both these liquors having stood in the same room that they might be reduc'd by the same Ambient Air to a like degree of coldness the event of this Trial was what I look'd for that the oyl of Turpentine notwithstanding its actual coldness and the great subtilty and piercingness of parts which it has in common with other Chymical oyls being of an incongruous Texture seem'd not to make any dissolution of the powdered Lime and did not for several hours that I kept it produce that I perceived any sensible heat in the Lime Whereas to show that 't was not the fault of the Lime that part of it on which common water had been poured did after a little while conceive so strong a heat that it broke a large openmouth'd-glass into whose bottom it was put and not only grew so hot that I could not endure to hold it in my hand but sent out at the mouth of the glass though that were considerably distant from the Lime a copious white fume so hot that I could not well suffer the holding of my hand over it And to prevent a possible though invalid objection which I foresaw might be drawn against the Experiment made with oyl of Turpentine from the Oleaginous Nature of that liquor I covered a piece of the same sort of quick-Lime I have been speaking of with highly rectified spirit of Wine but though I left them together all night yet I perceived not that the liquor had at all slack'd the Lime which continued in an intire lump till upon the substituting of common water it did as I remember quickly appear to be slack'd since it fell assunder into a kind of minute white powder which was bating the colour almost like mud and would easily by a little shaking be disperst like it through the water 15. Eleutherius I ingeniously confess to you Carneades that what you say surprizes me for I thought it superfluous to try my self so acknowledged an Experiment being not able to imagine that so many learned men for so many Ages should so unanimously and confidently deliver a matter of fact of which if it were not true the falsity could be so easily discovered 16. Carneades For my part Eleutherius I confess I am wont to doubt of what they teach that seldom or never doubt And I hope you will forgive me if having found an assertion so general and uncontroul'd of a falsity so easie to be disprov'd I be inclinable to suspect the Truth of their other inferior Traditions about Antiperistasis and of these I will mention the two chiefest I have met with among the moderns for being contriv'd Experiments I presume you will easily believe they came not from Aristotle nor the Ancienter Schoolmen that commented upon Him 17. The first of these is the freezing a Pot to a Joynt-stool by a mixture of snow and salt by the fires side in which case 't is pretended that the fire does so intend the cold as to enable it to congeal the water that stagnated upon the surface of the stool betwixt That and the bottom of the Pot. But how little need there is of Antiperistasis in this Experiment you may guess by this that I have purposely made it with good success in a place in which there neither was nor ever probably had been a fire the room being destitute of a Chimney And this Trial of mine I could confirm by divers other Experiments of the like nature but that this one is sufficient 18. I proceed therefore to the other Experiment which is delivered by very learned men and for whom I have a great respect according to these if you take a somewhat large Pot and having fill'd it almost with snow place in the midle of the snow a Vial full of water this Pot being put over the fire the coldness of the snow will be so intended by the heat from which it flies into the water that it will turn that liquor into ice But though I several times tri'd this Experiment yet neither in earthen nor in silver vessels could I ever produce the promised ice And I remember that an eminently learned man that wondered to find me so diffident of what he said he knew to be true readily undertook to convince me by an Ocular proof but with
in motion become vehemently cold in their passage For Mr. Hobs cannot as other Naturalists derive the coldness of freezing winds from the cold steams they meet with and carry along with them in their passage through cold Regions since then those steams rather then the wind would be the cause of that vehement coldness and so it might justly be demanded whence the coldness of those cold exhalations proceeds Besides that 't is very precarious and unconsonant to observation to imagine such a wind as he talks of to blow whenever great frosts happen since as we noted before very vehement glaciations may be observ'd especially in Northern Regions when the air is calm and free from winds 19. The account he gives in his seventh Section of turning water into ice is the most unsatisfactory I have ever yet met with for a good part of that Section is so written as if he were affear'd to be understood But whereas he supposes that by the indeavour of the wind to raise the parts of the water joyn'd with the indeavour of the parts of the water towards the Center of the Earth the uppermost parts of the water will be prest together and coagulated he says that which is very far from satisfactory For first ice is often produced where no wind can come to beat upon the uppermost parts of the water and to raise them and in vessels Hermetically seal'd which exactly keep out air and wind ice may be generated as many of our Experiments evince And this alone were a sufficient answer since the whole explication is built upon the action of the wind But this is not all we have to object for not to urge that he should have prov'd that the uppermost parts of the water must be raised in congelation especially since oyl and divers other liquors are contracted by it not to urge this I say what shew of probability is there that by the bare indeavour of the wind and the gravity of the superficiate parts of the water there should be any such forcible compression made as he is pleas'd to take for granted And yet this it self is less improbable then that supposing the upermost parts of the water to be pressed together that pressure is sufficient to coagulate as he speaks or rather congeal them into ice So bold and unlikely an assertion should at least have been countenanced by some plausible reason or an example in some measure parallel For I remember not any one instance wherein any degree of compression that has been imploy'd much less so slight a one as this must be considering the causes whence 't is said to proceed can harden any liquor into ice or any other hard body And in the Experiment we have elsewhere mentioned of filling a Pewter vessel with water and when 't is exactly clos'd compressing it by the knocks of a Hammer till the water be reduc'd to penetrate the very Pewter we found not that so violent a compression did give the water the least disposition to turn a hard body And as for the way Mr. Hobs assigns of Increasing the thickness of ice 't is very difficult to conceive how a cake of ice on the top of the water being hard frozen to the sides of the containing vessel and thereby severing betwixt the included water and the external air the wind that cannot come to touch the water because of the interposition of the hard and rigid ice should yet be able sometimes at the depth of nine or ten foot or much further to beat upon the subjacent water and turn it into ice And it is yet more difficult to conceive how the wind must do all this when as was lately noted the water does very often freez more and more downwards to a great depth in places where the wind cannot come to beat upon it at all And as to what Mr. Hobs further teaches that the ice must contain many particles of air receiv'd into it we have elsewhere occasion to show how 〈◊〉 he discourses about those Icy Bubbles 20. The reason he assigns of the freezing of water with Snow and 〈◊〉 does as little satisfie as the rest of his Theory of Cold. For not to mention that he affirms without proving it that Snow and Salt have in them a great deal of air it is very precarious to assert that this air must be prest out every way in wind which must rake the sides of the vessel for 't is strange that far more diligent observers then Mr. Hobs should take no notice of any such wind if any such wind there were but this is yet less strange then that which follows namely that this wind must so rake the sides of the vessel as to make the vessel by the same motion and action congeal the water within it For what affinity is there between a wind passing along the outside of a glass altogether impervious to it and the turning a fluid body included in that glass into a hard and brittle body The wind indeed may perhaps if it be strong a little shake or agitate the particles that compose the glass and those may communicate some of their motion to the contiguous parts of the water but why all this must amount to the turning of that water into ice is more I confess by far then I can apprehend Especially seeing that though you long blow upon a glass of water with a pair of Bellows where there is not an Imaginary wind as Mr. Hobs's but a Real and manifest one yet the water will be so far from being frozen that our formerly mentioned Experiments of blowing upon Thermometers make it probable that it will scarce be cool'd And if Sea-salt do contain so much air by vertue of which it as well as the Snow produces so intense a degree of Cold how chance that being resolv'd in a little water without Snow it does not produce at least a far greater degree of cold then we find it to do Besides in the Experiment we made and elsewhere mention of freezing water seal'd up in Bubbles though the Bubbles were suspended in other glasses whose sides no where touched them and the remaining part of whose cavities were fill'd some with air and some with unfreezing liquors what likelihood is there that Mr. Hobs's insensible Wind should be able to occasion so many successive Rakings through differing Bodies as there must be to propagate the congelative motion if I may so call it of the wind through the first glass to the included Air or Liquor and through that new Medium to the glass containing immediately the water and through that to the innermost parts of the seal'd up water And it might be further objected if it were worth while that Mr. Hobs does not so much as offer at a reason why spirit of Wine Aqua fortis or even Brine if it be of the strongest sort are not either by this mixture or here in England by the Wind in the open