I shall content my self to make use of this obvious 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 of Cold that in Rivers Ponds and other receptacles of water the congelation begins at the Top where the liquor is expos'd to the immediate contact of the Air which sufficiently argues that the Air is colder then the Water since it is able not only sensibly to refrigerate it but to deprive it of its fluidity and congeal it into Ice whereas if the water it self were the primum frigidum either it ought to be at least as to the major part of it always congeal'd or we may justly demand a reason why when it does freez the glaciation should not begin in the middle or at the bottom as soon as at the Top if not sooner And our Arguments against the precedency of the water in point of coldness may be strengthen'd by this That frosts are wont to be hardest when the Air is very clear and freest from Aqueous vapors whereas in rainy weather wherein such vapors most abound the cold is wont to be far more remiss To which we may add what we lately deliver'd from the observation of Navigators that even in the frigid Zone the main Sea where yet the water is in the greatest mass and so most likely as well as advantag'd to disclose its nature never freezes though the Straits and Bays and Gulphs be frozen over which argues that the greatest degrees of Cold are rather to be assign'd to the Air or to the Earth then to the Water which by the practise formerly mention'd of the Masters of the French Salt Marshes appears to be when it is of a considerable depth fitter to preserve Bodies from congelation then to congeal them which instance I the rather repeat because it seems to argue that the water is not so much as dispos'd to receive any very intense degree of cold at a remote distance from the Air for though Navigators tell us of exceeding thick pieces of Ice yet as we have already elsewhere noted we are not bound to believe that the congealing cold has pierced any thing near so much as that thickness amounts to from the superficies of the Sea directly downwards for though it were no great matter if it did in comparison of that depth of the Sea which though the water be naturally cold the sharpest Air is unable to congeal yet we have elsewhere proved that those thick masses of Ice are not solid and intire pieces but rather heaps of many 〈◊〉 and other fragments of Ice which running upon one another or sliding under one another are by the congelation of the intercepted water and perchance half thaw'd snow as it were cemented together into mis-shapen and unweildy masses which conjecture agrees very well with that observation of the Ingenious Captain James which he delivers in these words It seldom rains after the middle of September but snows and that snow will not melt on the lands nor sands At low water when it snows which it doth very often the sands are all covered over with it which the half tide carries 〈◊〉 ously twice in twenty four hours into the great Bay which is the common Rendezvous of it Every low water are the sands left clear to gather more to the increase of it Thus doth it dayly gather in this manner till the latter end of Octob. and by that time hath it brought the Sea to that coldness that as it snows the snow will lye upon the water in flakes without changing its colour but with the wind is wrought together and as the Winter goes forward it begins to freez on the surface of it two or three inches or more in one night which being carried with the half tide meets with some obstacle as it soon doth and then it crumples and so runs upon it self that in few hours it will be five or six foot thick the half tide still flowing carries it so fast away that by December it is grown to an infinite multiplication of Ice Thus far this Navigator to which I shall add another passage out of one of his Countreymen Mr. Hudson famous for the Northern Discoveries that bare his name by which added to what has been elsewhere deliver'd to the same purpose we may be invited to believe that the vast Hills and Islands of Ice that are to be met with about the Straits of Weigats and elsewhere are not generated of the Sea it self It s no marvel says he that there is so much Ice in the Sea towards the Pole so many Sounds and Rivers being in the Lands of Nova Zembla and Newland to ingender it besides the coasts of Pechora Russia and Greenland with Lappia as by proof I find by my Travel in these parts 15. But for all this I think not fit as does the Ingenious Gassendus and some others to make the water indifferent as to heat and cold For as I formerly noted concerning the Earth so I must now represent touching the water that setting aside the 〈◊〉 of the Sun which is but adventitious where it does operate and 〈◊〉 〈◊〉 many vast portions of that Element which it 〈◊〉 not 〈◊〉 reach the insensible parts of water are much less agitated then those of our Sensories temperately dispos'd and consequently may in regard of us be judg'd cold For though water being a Liquor I readily allow it a various Motion of its component Corpuscles that being requisite to make a Body fluid yet such an agitation which is sufficient for fluidity may be and often is far more remiss then that of the spirits Blood and other liquors of so hot a Sanguineous animal as Man as we see that Urine though after it has been long omitted it continues a fluid Body yet its parts are far less agitated then they were when it came hot and reeking out of the Bladder 16. And upon this occasion I shall add what by inquiry I have learned that except the parts somewhat near the superficies of the water which the heat of the Sun or the warmth of the neighbouring lower Region of the Air may give some warmth to the whole Body of the Sea is very cold for being very well acquainted with one that for some time got a livelihood by going down into the Bottom of the Sea to fetch up what could be recovered out of shipwrackt vessels I purposely inquired of him what cold he felt under water and he more then once told me that though near the Top of the water the cold were very moderate yet when he was necessitated to descend a great depth he found it so great that he could not very long support it and particularly he told me that having occasion to descend about twelve or fourteen fathom deep which is nothing in comparison of the depth of many Seas to fasten ropes to the Ordinance of a great ship that was some years since cast away near the coast of one of the Northern Countries though the Engine that was let down
with him supplied him so well with Air that he was not incommodated in point of Respiration and though he felt no other inconveniencies that might disswade his tarrying longer yet the cold was so great and troublesome that he was not able to endure it above two or three hours but was constrain'd to remount to a milder as well as a higher Region I wish'd several times he had had with him a seal'd Weather-glass for ordinary Thermometers would on that occasion have been unserviceable to prevent some little doubt that might be made whether the intense Cold he felt might not be only and chiefly in reference to his Body which might be so alter'd and dispos'd by this new Briny Ambient as to make such a disturbance in the course or texture of his Blood as that which makes Aguish persons so cold at the beginning of the fit though the temperature of the Ambient Body continue the same But this is not the only person that found the Sea Exceeding cold for I remember Beguinus relates from the mouth of a Marseillian Knight that was overseer of the Coral-fishing in the Kingdom of Tunis that having upon that coast let down a young man to feel whether Coral were hard or soft as it grew in the water when this man was come about eight fathom near the Bottom of the Sea he felt it exceeding cold To which we shall add the testimony of a sober Traveller Josephus Acosta who tells us That it is a thing remarkable that in the depth of the Ocean the water cannot be made hot by the violence of the Sun as in Rivers Finally he subjoyns even as Salt-Petre though it be of the nature of Salt hath the property to cool water even so we see by experience that in some parts and havens the salt water doth refresh the which we have observed in that of Callao where they put the water or wine which they drink into the Sea in Flaggons to be refreshed whereby we may undoubtedly find that the Ocean hath this property to temper and moderate the excessive heat For this cause we feel greater heat at Land then at Sea caeteris paribus and commonly Countries lying near the Sea are cooler then those that are farther off By all these testimonies it seems to appear that both in very cold Regions and very hot the deep parts of the Sea seem to be very Cold the Sun beams being not able to penetrate the Sea to any great depth for I remember that having enquired of the Diver I lately mentioned whether he could discern the light of the Sun at any great distance from the surface of the water he answered me that he could not but as he went down deeper and deeper so he found it darker and darker and that to a degree that would scarce have been expected in so Diaphanous a Body as water is 17. But this submarine cold if I may so call it though it be great and considerable is not so intense as to intitle water to be the primum frigidum since as cold as our Divers found it at the bottom of the Sea they did not find it cold enough to freez the water there as the Air often does at the Top. 18. The next Opinion we are to consider is that of the Stoicks of old and adopted by the generality of Modern Philosophers that are not Peripateticks who assert the Air to be the primum frigidum But being ere long more particularly to treat of the Temperature of the Air we will reserve till then to examine whether it be cold of its own nature or not but in the mean time we shall here take leave to question whether it ought to be esteem'd the primum frigidum For not to mention that Aristotle and the Schools with many other learned men think the Air so far from being the coldest of the Elements that they reckon it among the hot ones because I confels their opinion is not mine not to represent the heat of the Air in the Torrid Zone nor that by the generality of Philosophers the upper Region of the Air which is believed to make incomparably the greatest part of it is always hot and the lower Region is so too in comparison of the middle though the coldness even of this is not perhaps unquestionable not to urge any of these things I say I shall in this place mention only two observations 19. The one is that which I lately recited touching the great coldness of the water in the deeper parts of the Sea for'tis not easie to show how this great cold proceeds from that of the Air whose operation seems not as may be judg'd by that little way that frosts pierce into the moist Earth to reach very far beneath the surface of the water insomuch that Captain James who had very good opportunity to try allows not in case the Ice be not made by accumulation that the Frost pierces above two yards perpendicularly downwards from the surface of the water even in the coldest habitable Regions And this will seem the more rational if we consider that in case the coldness of the Sea proceeded constantly from the Air as such the cold would be greater near the surface where 't is contiguous to the Air then in the parts remoter from it and yet the contrary may appear by the passages lately recited 20. But if it be objected that this at best can prove no more then that the Air is not the primum frigidum notwithstanding which it may be the summum frigidum For answer I must proceed to my second Argument which will perhaps evince that it is not that neither for by the same way of arguing by which those I am now dealing with endeavour to prove the Air to be the coldest Body in the World I shall endeavour to prove that it is not so For their grand and as far as I remember their only considerable Argument is drawn from Experience which shows that water begins to freez at the Top where 't is exposed to the Air but to this vulgar Experiment I oppose that of mine which I have often mentioned already to other purposes that by an application of salt and snow I can make water that would else freez at the Top begin to freez at the Bottom or at any side I please and that much sooner then the common Air even in a sharp frosty night would be able to congeal it and when in exceeding cold weather the Ambient Nocturnal Air had reduc'd a parcel of Air purposely included in a convenient glass to as great a degree of condensation as it could I have more then once by the External application of other things been able to condense it much farther which argues that 't is not the Air as such but some adventitious frigorifick Corpuscles taking that term as I do in this Treatise in a large sense that may sometimes be mingled with it which produce the notablest degrees of
Cellars and other subterraneal cavities where consequently they produce such a heat as to those that come out of the cold air may be very sensible And the rather because whilest men by the coldness of the season are more then ordinarily careful to stop up the passages at which the external air may get in they do though designlesly stop up the vents at which the subterraneous exhalations might get out And to shew you that this last circumstance is not impertinently taken notice of I shall tell you that a very grave Author having occasion to mention Cellars relates it as a practise in divers houses of a Town where he had been to keep vents in their deep Cellars which in the Summer were from time to time opened partly to keep the places sweet and wholsom and partly to let out the warm Exhalations that would else hinder their liquors from keeping so fresh and well And these steams were affirm'd to have been several times taken notice of to ascend visibly into the free air like a smoak which several Phaenomena and particularly what I formerly related of the hot fumes that manifestly ascended out of the great Groove in the Hungarian Mine may keep us from thinking incredible 40. And now by what I have hitherto discours'd I have made way for the solution of a Phaenomenon that is wont to be much urg'd in favour of Antiperistasis namely the smoaking of water that is drawn in frosty weather out of deep Wells and Springs 41. But first I must advertise you that 't is improperly enough that some urge for Antiperistasis such examples as the strange Spring near the Temple of Jupiter Ammon which Lucretius and others have observed to have been exceeding cold in the day time and as hot at night for not now to examine whether this story be not fabulous or might not be ascrib'd to some crafty trick of the Idolatrous Priests that had a mind to impose upon Alexander as well as others and procure an admiration to the place I consider that this and other the like cases such as are the Springs mentioned in the Islands of Maldiviae by Pyrard a French Author that was shipwrack'd and liv'd long in those parts must be referred to the peculiar Nature of the Springs or some other hidden cause since if the water of them were but ordinary and the Phaenomena were the effects of Antiperistasis it might justly be expected that the like should happen in all Springs or at least in very many which that it does not common experience shows us And I would say that this might be the case of the Spring you mention out of Captain James's Voyage but that besides that he does not say expresly that it was frozen in July but only that then it afforded him no water which might happen upon divers other accounts And besides that 't is manifest that in far hotter Countries where the excessive heat of the Air might more intend the subterraneal cold if Antiperistasis could do it there is no talk of any such degree of cold in Summer as to freez the Springs besides this I say there seems to be through some mistake or other a contradiction in the relation it self since in the same Voyage speaking of the same month of December he expresly says that their Well was then frozen up so that dig as deep as they could they could come by no water And he complains on that occasion of the unwholsomness of melted snow-water 'T is true that he soon after mentions a Spring that he found under a hills side which did not so freez but that he could break the ice and come to it but by his very sending far from his house to that Spring it appears to have been a Consequence and therefore a Proof of the uselesness of his Well in December as his affirmation that it continued all the year so as to be serviceable when the ice was broken shows that the Antiperistasis did not freez it up in Summer And having cleared my self of such a Testimony of this ingenious Navigator as would appear very illustrious if there had been no mistake about it I shall not scruple to add that the late publisher of the Latin Description of Denmark and Norway informs us that in or near that little Danish Island 〈◊〉 wherein the famous Tycho built his Urani-Burgum there is one Spring among many ordinary ones that even in the coldest Winter is never frozen which subjoyns my Author does in these regions exceeding rarely happen to be found Olaus Magnus also relates that in another part of the King of Denmarks Dominions namely near Nidrosia one of the chief Cities of Norway there is a Lake that even in that Northern Region never freezes And the learned Josephus Acosta mentions that among a very great number of hot Springs to be met with in Peru At the Baths which they call the Baths of Ingua there is a course of water which comes forth all hot and boiling and joyning unto it there is another whose water is as cold as ice He adds That the Ingua or the Peruvian Emperor was accustomed to temper the one with the other and that it is a wonderful thing to see Springs of so contrary qualities so near one to another These relations as I was saying I scruple not to mention though at first sight they may seem to disfavour my cause For by these and some others it may appear that Springs may obtain very peculiar and strange qualities from the nature of the places whence they come or through which they pass or from some other causes that are as hidden from us as the originals of these rare waters And this being once prov'd who knows what interest such causes as we are strangers to may have in some Phaenomena that are wont to be wholly ascrib'd to the heat and cold of the superficial part of the ground and what influence they have upon many other Springs besides those above mentioned some of which that are very deep may rise from the warm region of the Earth where they may be affected by the place as both these and others may be by Mineral juices and steams such perhaps as we know nothing of though we well know that some of them that are saline without being at all sensibly hot will powerfully resist congelation 42. But having hinted thus much on this occasion I shall now proceed to consider The smoaking of waters drawn from deep places in frosty weather and show that it does not necessarily conclude such water to be warmer in Winter since that effect may proceed not from the greater warmth of the water in such weather but from the greater coldness of the Air. For we may take notice that a mans breath in Summer or in mild Winter weather becomes very visible the cold ambient Air nimbly condensing the fuliginous steams which are discharg'd by the Lungs and which in warmer weather are
by the Diary the Quicksilver to have ascended but to 29 Inches and a pretty deal less then a half Since that time being forced by several Avocations to be often absent from the place where my Thermoscopes were kept I was not careful to prosecute such Observations those already set down not to mention those that are not here transcrib'd being judg'd abundantly sufficient to evince the Paradox propos'd to be prov'd by them Only to manifest that after I desisted from registring my Observations the Phaenomena may probably have been as remarkable as before I shall add That one of the last times I chanc'd to take notice of the Difference to be gather'd by comparing the two Weather-glasses I found the weather happening to be warmer then ordinary the difference between them to exceed any that I remembred my self to have then observ'd amounting to forty four if not to forty five Divisions And ev'n since the writing of the Last Line we have had opportunity to observe a Phaenomenon which if it had occurr'd to us in the place where we might have compar'd the Barascope with the Exact Weather-glasses hitherto mention'd and whereby we had been invited to rely upon it would perhaps appear more Considerable then any of the Observations yet recorded For not very many hours ago finding in the Morning the Quicksilver to be risen in a good Barascope of mine though another from that all this while referred to and elsewhere kept above ¾ of an Inch higher then the place it rested at the Night foregoing and a somewhat Nice Weather-glass where the included Air is kept in the lower part of the Instrument which is shaped like that already describ'd in this Discourse being consulted to show what Effect so great and sudden a change of the Atmosphaeres gravity would have upon it I saw the tincted Liquor in the shank depress'd a full Inch or more beneath the Surface of the Ambient Liquor in the Viol which strange depression of the Liquor in a pipe above 20 Inches long and where the alterations of the Air as to Heat and Cold are not wont to produce any thing near so great an Effect I could not but take much notice of Since the season of the year makes it no way likely that the night though Cold could have had so powerful an Operation on it especially since an Amanuensis that watch'd it much longer then I affirms that he saw the Liquor driven down quite to the very Bottom of the pipe and a Bubble of the outward Air to make its passage through the water and to joyn with the Air contain'd in the cavity of the Viol. The II. Discourse Containing some New Observations about the Deficiencies of Weather-glasses together with some Considerations touching the New or Hermetical Thermometers ANd since I had occasion to speak of the Deficiencies of Weather-glasses and the mistakes whereto men are liable in the Judgement they make of Cold and Heat upon Their Informations it will not perhaps appear impertinent to add three or four Considerations more to excite men to the greater Wariness and Industry both in the making and using Weather-glasses and in their Judging by them 1. And first I consider that we are very much to seek for a Standard or certain Measure of Cold as we have setled Standards for weight and magnitude and time so that when a man mentions an Aker or an Ounce or an Hour they that hear him know what he means and can easily exhibit the same measure but as for the degrees of Cold as we have elsewhere noted concerning those of Heat we have as yet no certain and practicable way of determining them for though if I use a Weather glass long 't is easie for me to find when the Weather is colder or when warmer then it was at the time when the Weather-glass was first finished yet that is a way of estimating whereby I may in some degrees satisfie my self but cannot so well instruct others since I have no certain way to know determinately so as to be able to communicate my knowledge to a remote Correspondent what degree of Coldness or Heat there was in the Air when I first finished my Thermoscope For besides that we want distinct Names for the several gradual differences of Coldness we have already declar'd that our sense of feeling cannot safely be relied upon to measure them and as for the Weather-glass that is a thing which in this case is suppos'd to be no fit Standard to tell us what was precisely the temper of the Air when it self was first finished since that does but inform us of the recessions from it or else that the Air continues in the Temper it was in at the making of the Instrument but does not determine for us that Temper and enable us to express it as indeed it is so mutable a thing ev'n in the same place and oft-times in the same day if not the same hour that it seems little else then a Moral impossibility to settle such an universal procurable Standard of Cold as we have of several other things And indeed there is scarce any Quality for whose differences we have fewer distinct Names having scarce any for the many degrees of Coldness that may be conceiv'd to be intermediate betwixt Lukewarmness and the Freezing degree of Cold and even these are undefin'd enough for that which to some mens senses will feel Lukewarm by others will be judg'd Hot and by others perhaps cold nor is even the glaciating degree of Coldness well determin'd since not only differing Liquors as oyl wine and water will manifestly freez much more easily one then another but even Liquors of the same denomination and of waters themselves some are more easily turn'd into Ice then others and I see no great cause to doubt but that there may be sufficiently differing degrees of Cold whereof the mildest may suffice for the congelation of some waters I must not forget to add that the same person that has made many observations with a Weather-glass is so confin'd by that numerical Instrument that if by the spilling of the Liquor or the cracking of the Glass or the casual intrusion of some Bubbles of Air or by any of divers other Accidents that may happen the Instrument should be spoil'd he would though he should imploy again the same Instrument be reduc'd to seek out 〈◊〉 new Standard wherewith to measure the varying temperature of the Air. And though it be not difficult to include in the Cavity of a Weather-glass some other fluid Body instead of Air yet it will be very difficult if not impossible to include a Body fit to resent and show the Alterations of the Ambient Air without being also liable to receive impressions from it at the time of its being first shut up Yet I will not here omit that I have sometimes consider'd whether the essential oyl of Aniseeds which is that that is distill'd by the intervention of water in a
down in the slender Stem of a small Weather-glass then the spirit of Wine it self as we have elsewhere shown that when Air is not forc'd a Bubble of it will not in several cases so readily pass through a very narrow passage as would that grosser fluid Water But all these difficulties not to call them extravagances which I have been mentioning about seal'd Weather-glasses I represent not to show that it is at least as yet worth while to suspect ours so far as to imploy all the Diligence and Inventions that were 〈◊〉 to prevent or silence the suspicions of a Sceptick or that might be thought upon in case the matter did require or deserve such extraordinary Nicety but only to give men a rise to consider whether it would be amiss to take in when Occasion presents it self as many collateral Experiments and Observations as conveniently we can to be made use of as well as our Sensories and Weather-glasses in the Dijudications of Cold. And perhaps an Attentive Enquiry purposely made would discover to us several other Bodies Natural or Factitious which we might make some use of in estimating the degrees of Cold. For though to give an instance 〈◊〉 be thought the Liquor that is most susceptible of such an Intensity of Cold as will destroy or suspend its Fluidity yet not here to repeat what we formerly deliver'd of the easie congealableness of Oyl of Aniseeds we have as we elsewhere note to another purpose distill'd a substance from Benzoin which becomes of a fluid a consistent Body and may be reduc'd to the state of fluidity again by very much lesser alterations of the Ambient Air as to Heat and Cold then would have produc'd Ice or Thaw'd it I could also here take notice of what I have sometimes observ'd in Amber-greese dissolv'd in high rectifi'd spirit of Wine or in other Sulphurous or Resinous concretions dissolv'd in the same Liquor for now and then though it seem'd a mere Liquor in warm Weather it would in Cold weather let go part of what it swallow'd up and afterwards redissolve it upon the return of warm weather some of these concretions as I have seen in Excellent Amber-greese shooting into fine figur'd masses others being more rudely congeal'd And I might also add what I have observ'd in Chymical Liquors not unskilfully prepar'd out of Urine Harts-horn c. which would sometimes seem to be totally clear Spirits and at other times would suffer a greater or lesser proportion of Salt to Chrystallize at the Bottom according to the Mutations of the Weather in point of Cold and Heat Such kind of instances I say I could mention but I shall rather chuse to prosecute my Examples in that obviousest of Liquors Water and add that even That may afford us other Testimonies of the increased or lessen'd cold of the Air then that which it gives us in Common Weather-glasses For in some parts of France the Watermen observe that the Rivers will bear Boats heavier loaden in Winter then in Summer and I have upon inquiry been credibly inform'd that Seamen have observ'd their ships to draw less water upon the Coasts of frozen Regions where yet the Sea is wont to be less brackish then they do on our British Seas which argues that water is thicker and heavier in Winter then in Summer Nay I shall add that not only in differing Seasons of the Year but even at several times of the same day I have often observed the Coldness of the Air to be regularly enough so much greater at one time of the day then at another that a Glass bubble Hermetically seal'd and pois'd so as to be exactly of the same weight with its equal Bulk of Water as that Liquor was constituted at one time of the Day would about Noon when the warmth that the Summers Sun produc'd in the Air had somewhat rarifi'd the water and thereby made it bulk for bulk somewhat lighter then before the Bubble would sink to the Bottom of the water which for the better marking the Experiment I kept in a Glass-Tube but when at night the coolness of the Air had recondens'd the water and thereby made it heavier it began by little and little to buoy up the Bubble which usually by morning regain'd the Top of the Water and at other times of the day it not unfrequently happen'd that the Bubble continued swimming up and down betwixt the Top and the Bottom without reaching either of them sometimes staying so long in the same part of the Tube that it much surpriz'd divers of the Virtuosi themselves who thought the poising of a weight so nicely not only a very great difficulty as indeed it is but an insuperable one But of this Experiment I elsewhere say more and because about other Weather-glasses I have said so much already I think it may not be improper to Sum up my thoughts concerning the Criteria of Cold by representing the following particulars 1. That by reason of the various and unheeded predispositions of our Bodies the single and immediate informations of our senses are not always to be trusted 2. That though Common Weather-glasses are useful Instruments and the informations they give us are in most cases preferrable to those of our sense of touching in regard of their not being so subject to unheeded mutations yet ev'n these Instruments being subject to be wrought upon by the differing weights of the Atmosphaere as well as by Heat and Cold may upon that and perhaps some other accounts easily mis-inform us in several cases unless in such Cases we observe by other Instruments the present weight of the Atmosphaere 3. That the seal'd Weather-glasses we have been mentioning are so far preferrable to the Common ones as especially they not being obnoxious to the various pressure of the external Air that there seems no need in most cases to decline their reports or postpose Them to those of any other Instruments But yet in some nice Cases it may be prudent where it may conveniently be done to make use also of other ways of examining the Coldness of Bodies that the concurrence or variance to be met with in such ways of Examination may either confirm the Testimony of the Weather-glass or excite or assist us to a further and severer inquiry 4. That I would not have Men too easily deterr'd from devising and trying various Experiments if otherwise not unlikely or irrational about the estimating of Cold by their appearing disagreeable to the vulgar Notions about that Quality For I doubt our Theory of Cold is not only very imperfect but in great part ill grounded And I should never have ventur'd at trying to make seal'd Weather-glasses if I could have been withheld either by the grand Peripatetick Opinion that to shun a void water must remain suspended in Glasses where if it fall the Air cannot succeed it or the general opinion ev'n of Philosophers as well new as old That Air must be far easier then any visible Liquor
which more properly belongs to the Considerations about Heat where we have already handled it partly because our Design in the following Collections was not so much to gather and set down Observations that were obvious to any that was furnish'd with a Mediocrity of Attention as Experiments purposely made in order to the History of Cold and partly too because in this Collection though we do as occasion serves take notice of some Experiments and Phaenomena that relate to Cold in General or indefinitely yet our chief work has been to find out and deliver the Phaenomena of Congelation or of that intense Degree of Cold which either does freez the Bodies it works upon or at least were capable of turning common water fitly expos'd to it into Ice And this may serve for a general Advertisement about the ensuing Papers and consequently having premis'd it we shall without any further Preamble proceed to the setting down such things as we have tri'd and observ'd concerning those Matters beginning with those that belong to the Title prefix'd to the first Part or Section of our History 1. The Bodies that are cold enough to freez others are in this climate of ours but very few and among the most remarkable is a Mixture of Snow and Salt which though little known and less us'd here in England is in Italy and some other Regions much employ'd especially to cool Drinks and Fruits which men may easily do by burying in this mixture Glasses or other convenient vessels fill'd either solely with Wine or other Drinks or else with water that hath immersed in it the fruits to be refrigerated 2. The Circumstances we are wont to observe in making and employing this mixture we shall hereafter in due place deliver and therefore here we shall only take notice that we could not find upon some trials that such Glasses filled with water as would be frozen easily enough by this mixture of Snow and Salt would be in like manner frozen in case we employ'd Snow alone without mingling any Salt with it I deny not that 't is very possible that in very cold Countries as well Snow as beaten Ice may freez water powred into the Intervals of its Parts But there is great odds betwixt water so intermingled with Ice or Snow and only surrounded with it in a vessel where the water is as it were in one entire Body and of a comparatively considerable thickness And there is also a great Difference betwixt the degrees of coldness in 〈◊〉 Air of Frigid Regions and of England And perhaps too there may be some Disparity betwixt the Degrees of Coldness of Ice and Snow in those Climates and in ours And we must have a care that in case a Vial full of water buri'd all night should freez we ascribe not the Effect to the bare Operation of the Snow which may be entirely or in great Part due to the coldness of the Air which would perhaps have perform'd the Effect without the Snow 3. But though Snow and Salt mixt together will freez water better then Snow alone yet we must not think that there is any such peculiar vertue in Sea-salt to enable Snow to freez but that there are divers other Salts each of which concurring with Snow is capable of producing the like Effect For we found upon trial that we could freez water without the help of Sea salt by substituting in its place either Nitre or Alume or Vitriol or Sal Armoniack or even Sugar for either of those being mingled with a due proportion of Snow would serve the turn though they did not seem equally to advance the congealing power of the Snow nor scarce any of them did do it so well as Sea salt But of this elsewhere more 4. When we had made the newly mentioned trials some particular conjectures we have long had about the nature of Salts invited us to try whether uotwithstanding the comminution and consequent change produced in Salts by Distillation the Saline Corpuscles that abound in the distill'd liquors of those concretes as well as in their solutions would not likewise by being mixt with it enable Snow to freez water at least in small and slender Glasses This we first went about to try with good spirit of Salt but we found as we fear'd that though it made a sufficiently quick dissolution of the Snow it wrought upon yet its fluidity hindered it from being retain'd long enough by the Snow to the bottom of which it would fall before they had stay'd so long together as was requisite to freez so much as a little Essence-bottle full of common water 5. Wherefore we bethought our selves of an expedient whereby to try the operation not only of those spirits but of divers other bodies which were unapt for a Due commixture of Snow after the way newly mention'd or of which we had too little or valued them too much to be willing to spend quantities of them upon these trials And this way that remains to be mention'd we somewhat the better lik'd because the Experiments made according to it would also prove Experiments of the transmission of Cold through the extremely 〈◊〉 〈◊〉 of Glass And even in this way of trying we did at first meet with a discouragement which least it should happen to others we shall here take notice of namely that having put a convenient quantity of Snow into a somewhat thick green glass Vial though we copiously 〈◊〉 mixt with it a somewhat weak spirit of salt being loath to imploy the best we had and having well stopt the vessel did carefully 〈◊〉 together and thereby agitate the mixture in it yet the Glass appeared only bedew'd upon the outside without having there any thing frozen But suspecting that the thickness of the Glass might be that which hindred the operation of the included mixture we put snow and a convenient proportion of the self same spirit of salt into a couple of thin Vials one of which we clos'd exactly and the other negligently and having long shaken them we found that what adhered to them on the outside was though but somewhat faintly and thinly frozen 6. And as to this sort of Experiments we shall here observe 〈◊〉 〈◊〉 all that the Snow or Ice included 〈◊〉 with the Saline Ingredient whatever that were was always thaw'd within the Glass and that consequently 't was the condens'd vapor of the Air or other liquor that adhered to the outside of the glass which was turn'd into Ice which is the Reason why in mentioning these Experiments we often use the word freez in a transitive sense to signifie the operation of the frigorifick mixture upon other bodies 7. This premised let us proceed to relate that we afterwards took Oyl of Vitriol and mixing it with Snow in such an other vial as that last mentioned we found its freezing power far greater then that of spirit of salt And least it should be pretended that in these Experiments the cold was not transmitted
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
made much lighter by the heat of the ambient Air we might obtain the Information we desir'd to which we shall add That we also recommended to some Virtuosi that were likely to have the opportunity of gratifying Us that such an Experiment might be procured to be made in the midst of Summer in some part of Italy by the help of the there not unfrequent Conveniency of a Conservatory of snow wherein the water might be reduc'd to freez before the end of the same hour at whose beginning the there warmer Air had given it its greatest Expansion and so the Difference betwixt the Density of the same parcel of water might be the more conspicuous But as I have not received any Account of my Desires from abroad so coming now 〈◊〉 home to review the Memorial I caused to be written of the newly mention'd Observation I find that through the Negligence or Mistake of an Amanuensis there must needs be a manifest oversight committed in the 〈◊〉 down the Numbers which my Memory does not now enable me to repair And the season being now improper to repeat the Experiment as well as the numerical parcel of water I had kept and I imployed both times being thrown away I think it may be sufficient if not too much to have thus particularly intimated the way we took without ading the Cautions where with we proceeded nor what Trials we made to the same purpose with high rectifi'd spirit of Wine since unlucky accidents frustrated our Attempts 11. Whether the making of these kind of Trials with the waters of the particular Rivers or Seas men are to sail on may afford any useful estimate if and how much Ships and other Vessels may on those 〈◊〉 be safely loaden more in Winter 〈◊〉 in 〈◊〉 may be an 〈◊〉 of which I shall not in this place 〈◊〉 any 〈◊〉 Notice then to intimate thus much That the difference betwixt water highly refrigerated and that which is but of an usual degree of coldness is not so great as some 〈◊〉 〈◊〉 seem to have thought For on a Day which though made cold by snow intermingled with the rain that then fell was not a frost we took common water and weighed in it a glass Bubble whose weight in the Air was 150. grains and this Bubble weigh'd in that water lost so much of its former weight as to weigh about 28 â… grains and then by snow and salt reducing that water to such a degree of Coldness that it began to be turned into Ice about the inside of a small open glass that contain'd it we found the same Bubble not to weigh at all above one eighth part of a grain less then it did before So that if we may judge of the shrinking and condensation of the water by the Increment of weight it shrunk but about a 230. part of its former Bulk and this according to a pair of scales that would turn with about the 32. part of a grain which may keep us from wondring at what we lately delivered concerning the very inconsiderable subsidence of the water we exposed to snow and salt in a small Bolthead And it may also make that the more probable which we not long since related about the oyl of Turpentines not losing much above a 100. part of its Bulk by being expos'd to such a degree of cold as made water begin to freez Whether we may from this and from the formerly recited Experiment of the great subsidence of spirit of Wine in a seal'd Weather-glass safely conclude these subtile distill'd Liquors to be much more sensible then water of Cold as well as of Heat further Trials will best resolve and these I have not now so much opportunity as I could wish to pursue 12. But they that have a mind to prosecute Experiments of this kind and others that relate to the Degrees of Cold may perchance be somewhat assisted even by these Relations and especially by those Passages that mention the use of the seal'd Weather-glass furnish'd with spirit of Wine and of those wherein a drop of liquor is kept pendulous For the former of these being not subject to the Alterations of the Atmospheres 〈◊〉 nor as may be probably suppos'd by reason of the strength of the high rectifi'd spirit of Wine to be frozen by sending the same Weather-glass which may be made portable enough as I have tried by transporting one of them in a Case that might be easily carri'd even in a Pocket from one Countrey to another one may make far better Discoveries of the differing Degrees of Coldness in differing Regions and know somewhat near how much the Air even of Muscovy or Norway or Greenland it self is colder then that of England or any other Countrey whence the Weather-glass shall be sent The Instrument being accompanied with a memorial of the Degree it stood at when expos'd to such a Cold as made water begin to freez 13. The other Thermometer where a drop of liquor is kept pendulous may not only be imploy'd in such cases where the Pipe and Bubble can be erected upon the Horizon but by reason that the outward Air will indifferently impel the Bubble laterally or upwards upon the Refrigeration of the inward and that the bubble will not barely by its weight drop out of the inverted Instrument because of the resistence of the subjacent outward Air for these causes I say such a Thermoscope may as we have tri'd be also us'd where the Pipe shall be held Horizontal or inclin'd or even Perpendicularly downwards so that the flat Part of the Bubble may be appli'd to discover the Coldness either of the Wall or of the Ceiling of a room or other Bodies however scituated And if the Pipe be made long and even as sometimes we imploy one above a foot long not only sensible but great Effects of very little Disparities in the Coldness of Bodies to which the Instrument is appli'd may with pleasure be observed And the same drop of liquor may be long enough preserv'd useful in the Pipe But this Advertisement I shall give that as sensible as this Instrument appears to be of the nicer Differences of Coldness as of Heat yet they that shall have the Curiosity to examine with it as I have done the Temperature I say not of more resembling Bodies but of Liquors that may be thought to have their parts so differingly agitated as common Water high rectifi'd spirit of Wine and even rectifi'd oyl of Turpentine I add not Dephlegm'd oyl of Vitriol because of some odd Phaenomena not here to be insisted on will perhaps find the Event so little in many cases answer the Expectation he would have had of uniformly finding great Disparities in their actual Coldness if he had not met with this Advertisement that he will not much wonder that a Person who wants not other Imployments for his Time was willing to decline so tedious and nice a Task Title V. Experiments touching the Tendency of Cold Upwards
Estimate above deliver'd of the Expansion of water and that grand Hydrostatical Theorem demonstrated by Archimedes and Stevinus That floating Bodies will so far and but so far sink in the Liquor that supports them till the immersed part of the Body be equal to a Bulk of water weighing as much as the whole Body For Captain James in his often cited Voyage makes mention of great pieces of Ice that were twice as high as the Top-mast-head of his Ship 6. And the Hollanders in their famous Voyage to Nova Zembla mention one stupendious Hill of Ice which I therefore take notice of here not only because it has been thought the greatest that men have met with but because they deliver its Dimensions not as Captain James and Navigators are wont to do by comparison with the unknown heights of some of the Masts of their Ships but by certain and determinate Measures which in the Icy Island we are speaking of were so divided by the surface of the water that there was 16. fathome extant above it though there were but 36. beneath it which though a vast depth in it self yet 〈◊〉 but little exceed double the height And the Danish Navigator Janus Munckius imploy'd by his King to bring him an Account of Greenland mentions some floating pieces of Ice that he met with and observ'd in that Sea which though but somewhat above 40. fathome under water were extant 20. fathome that is near half as much above water whereas it seems that according to our above mention'd Computation of the Expansion of water the part under the water ought to be eight or nine times as deep as that above the water is high 7. To clear this difficulty I shall represent these three particulars First that in our Computation the Ice that sinks so deep is suppos'd to float in fresh water whereas in the Observations of the above nam'd Navigators those vast pieces of Ice floated on the Sea-water which by reason of its saltness being heavier then fresh-water Ice will not sink so deep into that as into this And that salt may hugely increase the weight of the water wherein it is dissolv'd may be clearly gather'd from the ponderousness of common Brine and from the practise of several sorts of Tradesmen who to examine the strength of their Lixiviums and other Saline Liquors are wont to try whether they will keep an Egg floating which we know common water will not do And I have also by the Resolution of some Metalline Bodies in fit Menstruums made Liquors that are yet much more ponderous then is sufficient for the support of Eggs. But yet we must be so candid as to take notice of what some Modern Geographers deliver with probability enough namely That nearer the poles the Seas are not wont to be so salt as in the temperate and the Torrid Zones and those Northern being not so salt as our Seas there is the less to be allow'd for the difference in gravity and consequently in the power to keep Ice from sinking betwixt those Seas and ours 8. But secondly this lesser saltness of the water in the Northern Seas may as to our case be recompenc'd by the greater coldness of it For though as we have formerly observed the Condensation of fresh water effected here by a degree of Cold capable to make it begin to freez is not so great as most men would imagine yet besides that I have often taken pleasure to make the same Body to sink or ascend in the same water by a much less variation 〈◊〉 Cold then that we have been mentioning it is to be consider'd that the degree of Cold to which water was brought in the Experiment deliver'd in the fourth Section to which we are now looking back was but such a degree as would make fresh water begin to freez whereas the salt Sea-water being indispos'd to congelation may by so vehement a Cold as reigns in the Winter season in those gelid Climates be far more intensly refrigerated and thereby more condens'd then common water is here by such a measure of Cold as may begin to freez small portions of it But though what we have hitherto represented may well be look'd upon as not inconsiderable to the purpose for which it has been alledg'd yet the main thing that is to remove the scruple suggested by the height of Icy hills above the water is 9. Thirdly that such Hills of Ice are not to be look'd upon as intire and solid ones but as vast piles or lumps and masses of Ice casually and rudely heap'd up and cemented by the excessive Cold freezing them together by the intervention of the water that washes them which piles of many pieces of Ice are not made without great Cavities intercepted and fill'd only with Air between the more solid Cakes or Lumps so that the weight of these stupendious pieces of Ice is not to be estimated by the bigness they appear of at a distance from the Eye but considering how much Air there is intercepted between the Icy Bodies of which they are compiled there may be a hollow structure of Ice reaching high into the Air and yet the whole Aggregate or Icy pile will press the subjacent water on which it leans no more then would as much water as were equal in Bulk only to the immers'd parts as we see in Barges loaden with Boards which though pil'd up to a great height above the water make not the vessel to sink more then a Lading that would make a far less show and oftentimes be all contain'd within the Cavity of the vessel provided it be more ponderous in specie But to enter into any further Consideration of these Hydrostatical matters would be improper in this place especially since we have elsewhere treated of them And that these floating Hills and Islands of Ice are not intire and solid pieces of it we shall otherwhere have occasion to shew out of Navigators and even in the Observation we have mentioned out of Janus Munck the Learned Relator of it Bartholinus takes notice that those vast pieces of Ice we have been mentioning that reach'd 20 fathome above water were compiled of store of Snow frozen together 10. These Considerations may serve to render some Account of those stupendiously tall pieces of ice whose extant part bears so great a proportion to the immersed part when the whole mass does really float But I confess I doubt that not only in the Examples we have alledg'd but in other eminent ones of mountains of ice if I may so call them there may be a mistake and that the height of them above the water would be far less and the depth under water far greater if the ice had water enough to swim freely For Sea-men by reason of the difficulty are not wont to measure the height of those pieces that float at liberty in the Sea And as for those that are on ground as their heights lye far more convenient
examine this having taken a piece of Ice we did not find upon trials that I partly made my self and partly caus'd in my presence to be made by others that if a mans Eyes were close shut he could certainly discern the Approach of a moderately siz'd piece of Ice though held never so near his fingers ends Nay which is more considerable having had the curiosity to make the Trial with one of those very sensible Thermoscopes I have formerly mention'd wherein a pendulous drop of liquor plays up and down in a slender pipe I found that by holding it very near to little Masses of snow somewhat compacted too the movable drop did not betray any manifest operation of so cold a neighbouring Body but if the glass were made to touch the snow the effect would then be notable by the hasty descent of the pendulous drop or its motion towards the obtuse part of the Instrument in case that were not perpendicularly but laterally appli'd to the snowy Lumps But this languidness of operation may perhaps proceed in great part from the smallness of the Pieces of Ice that were imploy'd For hearing of a Merchant that had made divers Observations about Cold in Greenland I desir'd by the mediation of a very learned Friend to be inform'd whether or no in the night they could perceive those vast heaps or rather mountains of ice that are wont to float up and down in that Sea by any new and manifest accession of Cold and was inform'd by way of Answer to that Question that being at Sea they could know the approach of Ice as well by the increase of Cold as by the glaring light which the Air seem'd to receive from the neighbouring Ice 3. But that which makes me suspect that there may in this account be some mistake is that I have not yet met with any like observation in any of the voyages into gelid Climates that I have had occasion to peruse though in some of them the Navigators frequently mention their having met with vast rands as some call them and Islands of mountainous ice in the night And 't is as I remember the complaint of one or two if not more of them that the Ship lay close by such vast pieces of ice without their being aware of it by reason of the fogs By which it seems that there was no sensible Cold diffused to any considerable distance whereby they might be advertised of the unwelcome neighbourhood even of so much ice But possibly the approach of far smaller masses of ice would have been sensible to them in such a Climate as ours where the organs would not have been indisposed to feel by a long accustomance of any thing near so intense a degree of Cold as that which then reigned in those Northern Seas 4. Whilest we were considering the Difference betwixt the operations of even the Coldest Bodies at the very nearest Distance and upon immediate Contact we thought it an Experiment not altogether unworthy to be tri'd whether though ice and snow alone that is unassisted by salts would not in some of our formerly mention'd Experiments freez water through the thickness even of a thin glass they may not yet do it when the water is immediately contiguous to them And I remember that we took a conveniently shap'd Glass and having frozen the contained water for some hours from the bottom upwards till the ice was grown to be of a considerable thickness we mark'd what part of the glass was possess'd by the unfrozen water and then removing the vessel to a little Distance from the snow and salt it stood in before we let it 〈◊〉 there to try whether the ice would freez any part of the contiguous and incumbent water but some intervening accidents hindred us from being able to derive any great satisfaction one way or other from our trial 5. Wherefore we shall add by way of Compensation that the diligent Olearius relates that at Ispahan the Capital City of Persia though it be seated in a very hot Climate and though it seldom freez there above a finger thick and the ice melt presently at Sun-rising yet the Inhabitants have Conservatories which they furnish with solid pieces of ice of a good thickness only by pouring at night great store of water at convenient intervals of time upon a shelving floor of Free-stone or Marble whereon as the water runs over it the most dispos'd of its parts are in their passage arrested and frozen by the contiguous ice which by this means says my learned Author may be brought in two or three successive nights to a very considerable thickness 6. We several times gave order to have this Experiment tried in England but partly through the negligence of those we imploy'd and partly upon the score of intervening circumstances our expectation was but ill answered And in this case I mention intervening circumstances because having caus'd a servant to pump in the night upon a not very thin plate of ice that was laid shelving upon a Board and another flat piece of Ice being about the same time laid under a place where water derived from a neighbouring spring is wont continually to drop he brought me word that not only in this last nam'd place the ice melted away but that under the pump instead of increasing in thickness by the waters running over it it was thereby rather dissolv'd At which somewhat wondring I went in the morning my self to the pump and causing a good flake of ice to be in a convenient posture plac'd under it I observed the water as it came out of the pump and was falling on the ice to smoak as if the depth of the Well had made the water though very Cold to the touch somewhat warm in comparison of the ice and thereby fitter to resolve then to increase it which inconvenience may be prevented by suffering the water of deep Springs and Wells to stand to cool in the Air before it be put to the Ice and this though the neighbouring Air were as I found by manifest proofs so cold that I was not tempted to impute the unsuccesfulness of the Experiment rather to its want of a sufficient coldness then the water's So that till I have an opportunity of making a further Trial I cannot 〈◊〉 more to the Persian way of augmenting ice But to proceed our having met with but an unsatisfactory Account of this Experiment which we were the more troubled at because this seem'd a promising way of trying that which otherwise is not so easily reduc'd to Experiment for the Temperature of the Air must be seriously consider'd in assigning the Cause of divers trials that may be made for the resolving of the same Question For to omit other Examples here in England we find that water poured on snow is wont to hasten the Dissolution of it and not to be congeal'd by it whereas having inquir'd of an Ingenious Person that liv'd a good while among the Russians
as our Author was descending into the golden Mine at Cremnitz he found in one place the heat to increase as he descended more and more which seems not to agree with a passage we lately mention'd out of him and to exceed any he had met with in any other Mine and afterwards the overseer bringing him into a room that abounded with smaragdine Vitriol the Mineral whence this heat proceeded though the room were spacious he found there besides a sharp spirit very offensive to his throat so troublesome a heat that he was ready to faint away with sweating and very much wondered how the diggers were able to work there And elsewhere the Author himself notes that such hot Mines of Vitriol or Sulphur may be found even in the first region of the earth as he calls that which is somewhat near the surface and which he thinks 〈◊〉 to name the cold region and within a large sphere of activity make it perpetually hot But this as I was intimating I mention but as a suspicion or a conjecture and notwithstanding that the degree of heat may be much increased in these Mines by the concurrance of accidental causes in case the conjecture be admitted yet since the frequency of a sensible degree of heat in very deep places does very little favour their opinion that will allow the earth to have no other heat but what it receives from the Sun beams or by the manifest fire of burning hills as Aetna and Vesuvius And if it should be objected that this Subterraneal heat is adventitious to the Earth which is supremely cold of its own nature Gassendus might reply that 't is as likely that the coldness of it near the superficies may be adventitious too and that it appears at least as manifestly that the one proceeds from the contiguous Air as it does that the other proceeds from some included fire and if I misremember not he hath this consideration that 't is somewhat strange that Nature should have intended the Earth for its summum frigidum and yet that a great part and for ought we know the greatest should be constantly kept warm either by the Sun as under the Torrid Zone or by the Subterraneal fires But the objection mention'd against Gassendus opposes but one of the Arguments we have alledg'd against the Earths being the primum frigidum and would leave the others in their force though it did more convincingly answer that against which 't is framed then it seems to do 10. And if the Patrons of the Earths coldness to evade the Arguments I have alledged should pretend that when they affirm the Earth to be the primum frigidum they mean not the Elementary Earth but some Body that is mingled with it I shall desire to know which 't is they mean of the many other Bodies that make up the Terrestrial Globe that we may examine what right it has to that Title and in the mean time I shall conclude against them that the Earth it self has none since they grant a colder Body then it and such a one as the earth must be beholding to for the greatest degrees of coldness it chances to possess 11. But though I presume enough has been said to make it appear unlikely that the Earth should be the primum frigidum yet I must in this dissent from the learned Gassendus that he thinks the Earth not only not to be the primum frigidum but not to be naturally cold any more then hot For the insensible parts of the Earth like those of other firm Bodies being heavy and perhaps gross and either having no constant motion at all or at least a far more remiss agitation then that of our Sensories it seems to follow that the Earth must seem cold to us unless it be by the communicated heat or motion of some extrinsick Agent put into a degree of agitation that belongs not to its nature and for the like reason I think it not improbable that pure Earth should in its own Nature be colder then either pure Water or pure Air since the Earth being a consistent Body its component particles are at rest among themselves or at least mov'd with an almost infinite slowness whereas Water and Air being fluids their component particles must be in a restless and various motion and consequently be less remote from heat which is a state wherein the various agitation of the minute particles is more vehement 12. And if those that plead for the Earth had declar'd that they meant not the pure or Elementary Earth but that part of the Terrestrial Globe that is distinct from the Sea and other Waters that make it up and would have Earth in that sense not to be the primum frigidum but only the summum frigidum perhaps they might have a better plea for their Opinion then they can urge for theirs who contend for the Water or the Air especially if to countenance their Opinion this memorable observation be added which I have met with among those Navigators that have had the greatest Experience of the Frigid Zone for the Dutch that sail'd thrice to Nova 〈◊〉 and once wintered there affirm in their first voyage that the highest degrees of Cold are not to be met with in the main Sea where yet men are most expos'd to the Operations of the Air and of the Water but either upon the Land or near it That accurate Geometrician and Hydrographer Fournier tells us that in 1595. the Hollanders being intercepted by Icy Scholes in the strait of Weigats and meeting with certain Muscovites demanded of them whether those Seas were always frozen and were answered that neither the Northern Sea nor that of Tartary did ever freez and that 't was only that strait with the Sea contiguous to the shores of some Bays and Gulphs that were frozen and our judicious Author not only adds that in effect all those that sail into those parts relate That all those Lumps of Ice are such as have been loosened and severed from the Islands and the Rivers of the Samojeds and Tartars but adventures to affirm in general terms that 't is certain the main Seas never freez and that 't is but the confines and shores of some of them that are frozen 13. That the water is the primum frigidum the Opinion of Aristotle has made it to be that of the schools and of the generality of Philosophers But I can as little acquiesce in this opinion as in the former not finding it agreeable to what experience teaches us 14. For not to mention that it would be very difficult to prove that divers very cold Bodies as Gold and Silver and Crystal and several other fusible stones have in them any water at all to which their coldness may with any degree of probability be ascribed nor to urge the Arguments that some Modern contenders for the supreme coldness of the Air are wont to imploy not I say to insist on such things
pottinger that contain'd the cold liquor began to freez at ¼ after ten That which contain'd the water heated and cool'd again began to freez ¾ past ten And that which contain'd the hot water at half an hour after eleven and somewhat better So that though all froze within the compass of two hours yet the cold water began this time to freez an hour and a ¼ sooner then the hot These pottingers were earthen but I elsewhere made the Trial in others of mettal and there also the cold water began to freez both before that which had been heated and cooled again and long before the hot Another time I measured out the water by spoonfuls into pottingers not having then by me any fit Scales to weigh it to be the more sure that the quantities of water should not be considerably unequal and then also the cold water froze a considerable while before the hot But my usual jealousie in the making nice Experiments tempting me to inquire whether the water in some of the former Trials had not been heated in a stone Bottle not a Skillet it was confess'd that it was so but that the bottle us'd to contain nothing but Beer and had been wash'd before-hand And though I did not think that the bottle could have any considerable influence on the Experiment yet least it should be suspected that the scalding water mighr have imbib'd some spirituous parts remaining yet among the minute dregs of Beer in the pores of the bottle for the greater security I caus'd the water to be heated in a Skillet and because in one of the Trials made in a Village where we had not choice of pottingers the cold water chanc'd to be put into one that afterwards seem'd less then that wherein the hot was expos'd I did this very day repeat the Experiment by putting cold water into a somewhat larger pottinger heating the other water in a Skillet and the event of the Trials is this That the cold water being put out with the rest at ¾ after 6. began to freez somewhat before ½ after 7. The water heated and cool'd again began to freez ¾ after 7. And having these frozen waters a pretty while by me I sent in for my own further satisfaction for the hot water and found it not to be in the least frozen at half a quarter after 8. So that supposing it to continue half a quarter of an hour longer before the beginning of its congelation it was twice as long ere it began to freez as the cold water had been By which we may see how well bestow'd their labour has been that have puzled themselves and others to give the reason of a Phaenomenon which perhaps with half the pains they might have found to be but Chymaerical I have been the more circumstantial in setting down these Trials that I may express a civility to so famous a Philosopher as Aristotle and also because Artificial Congelations which we can commonly best command and which we have the oftenest us'd about our other Experiments are not so proper for this For having formerly had the curiosity to take two pipes of glass made of the same Cylinder that they might be of equal bore and having seal'd each of them at one end and having fill'd both to the same height and then stirr'd them too and fro together in a mixture of beaten ice water and salt which mixture I make use of for the effecting sudden Congelations I found both waters to freez too quickly to make a notable disparity in the length of times that they remain'd uncongeal'd And we will not on this occasion omit one Phaenomenon afforded us by these Trials because it may admonish men how cautious they ought to be in making nice Experiments For having once made the formerly mention'd Trial with glass pipes that were but 〈◊〉 as not exceeding the 〈◊〉 of a mans fore-finger and having for greater caution put the hot water first into one glass and then into another we found one time that the hot water froze first and wondering at it we examin'd the glasses and perceiving one of them to be more Conical or acuminated where it had been seal'd up then the other it seem'd probable and afterwards appear'd true that the water in this acuminated part being suddenly frozen by reason of the slenderness of the glass there promoted and accelerated the Congelation of the rest so that whether it were the cold or the hot water that was put into that pipe it would thereby gain a manifest advantage In the foregoing Experiments made in pottingers I made use not only of cold and hot water but of water that had been heated and cool'd again though not reduc'd to its full pristine coldness to prevent the Objections of some that might pretend that such water would have frozen sooner then Cold which yet would not salve the common opinion which specifies not such water Postscript ANd it seems that such Cautions as I have been mentioning are not altogether useless For accidentally casting my eye upon the Circulus Pisanus of Berigardus upon Aristotles Meteors I somewhat wonder'd to find that an Author who is look'd upon to be a great adversary of Aristotle except in his dangerous and ill-grounded conceit of the eternity of the world and some other erroneous opinions does yet indeavour to justifie Aristotle by affirming that his Experiment will succeed if by heated water we understand that which having been heated is suffered to cool again till it be reduc'd to the temper of other water which was not heated For this refrigerated water he says he has found to congeal much sooner then the other water but this I confess I am very unapt to believe For having divers times caus'd cold water to be expos'd to the Air in frosty weather with that which had been heated and cool'd again and having set sometimes one of my Domesticks sometimes another to watch them the events did very much disfavour the assertion of our Author though care was had of the circumstances most considerable in such an Experiment as the matter size and shape of the vessels the equal degree of cold in the two several parcels of water into both which I sometimes dipp'd my finger to judge of them before they were expos'd and the place in which they were put both together to be frozen But for further satisfaction we elsewhere took two pottingers bought purposely for the making of Experiments of the same size and shape and in the same shop one of these we almost fill'd with cold water out of a glass wherein we mark'd how high that water reach'd that by filling the same glass to the same height with the refrigerated water we might be able to measure out the same quantity into the other pottinger This done I appointed one whose care I had no reason to distrust to examine the tempers of the several waters with a more then ordinarily sensible Weather-glass as a far safer
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
fires shining in the night sometimes in one place sometimes in another which were suppos'd to be kindled by the sulphurous and other subterraneous exhalations and that when they perceiv'd those fires especially if any number appear'd in several places those that were well acquainted with the coast would not continue long out at Sea but rather quit an opportunity of catching Fish then not make seasonably to the shore having often observed and particularly this last year that bold and unexperienced Mariners by slighting these forerunners of storms were in few hours shipwrack'd by them 48. To this I shall add what happened some years since upon the Irish coast near a strong Fortress called Duncannon where divers of the ships Royal of England lying at anchor in a place where they apprehended no danger from the wind there seem'd suddenly to ascend out of the water not far from them a black cloud in shape and bigness not much unlike a Barrel which mounting upwards was not long after follow'd as the most experienced Pilot foretold so hideous a storm as forc'd those ships to go to Sea again and had like to have cast them away in it And this account was both written by the principal officers of the Squadron to their superiors in England and given soon after it happened by the chief of those eye-witnesses and particularly by the Pilot to a very near kinsman of mine well vers'd in Maritine affairs that commanded the land forces in those parts as a truth no less known then memorable 49. And on occasion of what I was saying about the eruption of hot steams in several parts of the Earth I now call to mind something that I have met with in a very small but curious Dissertation De admirandis Hungariae aquis whose Anonymous Author I gather from some passages in the Tract it self to have been a Nobleman Governor of Saros and some other places in Hungary and to have written this discourse both for and to that inquisitive German Baron Sigis mundus Liber famous for the account he gave the world of the Ambassy whereon he was sent by the German to the Russian Emperor This Anonymous but noble writer tells us then that in that part of Hungary which he calls Comitatus Zoliensis there is a gaping piece of ground which does emit such mortal exspirations that they suffocate not only Cats and Dogs purposely held at the end of long poles over the cleft but kill even Birds that attempt to fly over it And in other places of the same Tract I have met with many other relations which if I had time to make a particular mention of would much countenance what I have been lately saying but though I pretermit several other instances I cannot but take especial notice of one which together with what I lately mention'd to have happened near Duncannon may make it probable that not only under the surface of the dry ground but in that part of the Terrestrial Globe that is covered with water there may arise streams and consequently Exhalations actually and that considerably hot For in one place he takes notice that not far from the well known City of Buda there is a hot Spring which they call Purgatory which the waters of Danubius it self are not able to keep from being hot nay within the very Banks betwixt which that great River runs there boil up hot Srings where those that will go deep enough into the water may commodiously bath themselves And elsewhere speaking of the River Istrogranum in the same County he adds That not only the Banks of it but within the very River it self one may discover hot Springs by removing the Sand at the bottom with ones feet To this I shall add That having heard of a Ditch in the North of England in some regards more strange though less famous then the sulphureous Grotta near Naples whence not only subterraneal steams but those so sulphureous as to be easily Inflamable did constantly and plentifully ascend into the Air I had the curiosity to make inquiry about it of the Minister of the place a very learned Man and conversant in Mines who then happened to be my neighbour and he attested the truth of the relation upon his own knowledge And it was confirm'd to me by a very ingenious Gentleman who went purposely to visit this place and found it true That a lighted Candle or some such actually burning body being held where this Exhalation issued out of the Earth would kindle it and make it actually flame for a good while and if I misremember not as long as one pleas'd And as this place was but few years since taken notice of so there may be probably very many others yet undiscovered that may supply the Air with store of Mineral exhalations proper to generate fiery Meteors and Winds I remember that having lately ask'd an inquisitive Gentleman that is a great searcher after Mines whether he did not observe some meteors near those places where he is most conversant he told me that 't is very usual in some of them to see certain great fires moving in the Air which in those places diggers because of some resemblance real or imaginary are wont to call Draggons And the Russian Emperors Physician you were speaking of inform'd me a while since that he had not long ago observ'd in Winter a River in Muscovy where though the rest of the surface was frozen there was a part of it near a mile long that remain'd uncovered with ice which probably was kept from being generated there by those subterraneous Exhalations since he says he saw them ascend up all the way like the smoak of an Oven And in case the matter of fact delivered by Olaus Magnus be true concerning the strange thaws that sometimes happen with terrible noises in the great Lake Veter those wonderful Phaenomena may not improbably be ascrib'd to the ascent of great store of hot subterraneal steams which suddenly cracking the thick and solid ice in many places at once produce the hideous Noises and the hasty Thaw that he speaks of And this suspicion may be countenanced partly by this circumstance that before these sudden thaws the Lake begins with great noise to boil at the bottom and partly by what is related by a more Authentick writer I mean that learned Traveller the Jesuite Martinius who witnesses that at Peking the royal City of China 't is very usual that after the Rivers and Ponds have continued hard frozen over during the Winter the Thaw is made in one day which since the freezing of the waters as he tells us required many makes it very probable That the sudden thaw is effected as he also inclines to think by subterraneal steams which I may well suppose to be exceeding copious and to diffuse themselves every way to a very great extent since they are able so soon to thaw the Rivers and Ponds of a large Territory and
possible cause of cold in those places that are near the Pole or where the obliquity of the Sun is great 4. How water may be congealed by Cold may be explained in this manner Let A. in the first figure represent the Sun and B. the Earth A. will therefore be much greater then B. Let E. F. be in the plain of the Aequinoctial to which let G. H. I. K. and L. C. be parallel Lastly let C. and D. be the Poles of the Earth The air therefore by its action in those parallels will rake the superficies of the Earth and that with a motion so much the stronger by how much the parallel Circles towards the Poles grew less and less From whence must arise a wind which will force together the uppermost parts of the water and withal raise them a little weakening their endeavour towards the Center of the Earth And from their endeavour towards the Center of the Earth joyned with the endeavour of the said wind the uppermost parts of the water will be press'd together and coagulated that is to say the top of the water will be skinned over and hardened and so again the water next the Top will be hardened in the same manner till at length the ice be thick And this ice being now compacted of little hard Bodies must also contain many particles of air receiv'd into it As Rivers and Seas so also in the like manner may the Clouds be frozen For when by the ascending and discendding of several clouds at the same time the air intercepted between them is by compression forced out it rakes and by little and little hardens them And though those small drops which usually make clouds be not yet united into greater bodies yet the same wind will be made and by it as water is congealed into ice so will vapours in the same manner be congealed into snow From the same cause it is that ice may be made by art and that not far from the fire for it is done by the mingling snow and salt together and by burying in it a small vessel full of water Now when the snow and salt which have in them a great deal of air are melting the air which is 〈◊〉 out every way in wind rakes the sides of the vessel and as the wind by its motion rakes the vessel so the vessel by the same motion and action congeals the water within it 5. We find by Experience that cold is always more remiss in places where it rains and where the weather is cloudy things being alike in all other respects then where the air is clear And this agreeth very well with what I said before for in clear weather the course of the wind which as I said even now rak'd the superficies of the Earth as it is free from all interruption so also it is very strong But when small drops of water are either rising or falling that wind is repelled broken and dissipated by them and the less the wind is the less is the cold 6. We find also by experience that in deep Wells the water freezeth not so much at it doth upon the superficies of the Earth For the wind by which ice is made entring into the Earth by reason of the laxity of its parts more or less loseth some of its force though not much So that if the Well be not deep it will freez whereas if it be so deep as that the wind which causeth cold cannot reach it it will not freez 7. We find moreover by experience that ice is lighter then water the cause whereof is manifest from that which I have already shown namely that the air is receiv'd in and mingled with the particles of the water whilest it is congealing 8. To examine now Mr. Hobs's Theory concerning Cold we may in the first place take notice that his very Notion of Cold is not so accurately nor warily deliver'd I will not here urge that it may well be Question'd whether the tending outwards of the spirits and fluid parts of the Bodies of animals do necessarily proceed from and argue heat Since in our Pneumatical Engine when the air is withdrawn from about an included viper to mention no other Animals there is a great intumescence and consequently a greater indeavour outwards of the fluid parts of the body then we see made by any degree of heat of the ambient Air wont to be produc'd by the Sun This I say I will not insist on but rather take notice that though Mr. Hobs tells us that to cool is to make the exterior parts of the body indeavour inwards yet our Experiments tell us that when a very high degree of Cold is introdnc'd not only into water but into Wine and divers other partly Aqueous liquors there is a plain intumescence and consequently indeavour outwards of the parts of the refrigerated Body And certainly Cold having an operation upon a great multitude and variety of bodies as well as upon our Sensories he that would give a satisfactory definition of it must take into his consideration divers other effects besides those it produces on humane bodies And even in these he will not easily prove that in every case any such indeavour inwards from the Ambient Aetherial substance as his Doctrine seems to suppose is necessary to the perception of Cold since as the mind perceives divers other qualities by various motions in the Nervous or Membranous parts of the sentient so Cold may be perceiv'd either by the Decrement of the agitation of the parts of the Object in reference to those of the Sensory or else by some differing impulse of the sensitive parts occasion'd by some change made in the motion of the blood or spirits upon the deadning of that motion or by the turbulent motion of those excrementitious steams that are wont when the blood circulates as nimbly and the pores are kept as open as before to be dissipated by insensible transpiration 9. It may afford some illustration to this matter to add That having inquir'd of some Hysterical Women who complain'd to me of their distempers whether they did not sometimes find a very great coldness in some parts of their heads especially at the Top I was answered that they did so and one of them complain'd that she felt in the upper part of her head such a Coldness as if some body were pouring cold water upon it And having inquired of a couple of eminent Physicians of great practise about this matter they both assur'd me that many of their Hysterical patients had made complaints to them of such great Coldness in the upper part of the head and some also along the Vertebra's of the Neck and Back And one of these Experienc'd Doctors added that this happen'd to some of his Patients when they seem'd to him and to themselves to be otherwise Hot. The noble Avicen also some where takes notice that the invenom'd Bitings of some kinds of Serpents creatures too well
a true 〈◊〉 or a coagulated substance that look'd just like Ice both 〈◊〉 eminent Virtuosi and I my self who had the Curiosity to 〈◊〉 it can bear him witness Lib. 1. Titulo de frig Asperitate pag. 9. This is pointed at in the third Page of the following Account where mention is made of an Honorable Person c. See the Publisher's Advertisement to the Reader * Among which I am since informed that he had tried divers before he saw my Papers * So one of the chief Passages of the Examen of Antiperistasis is much confirmed by the Forty Fourth and Forty Fifth Pages of the following Papers which contain an Account of a Trial made by the command of the Royal Society to whom it was proposed by the Author of the Examen with a request that they would be pleased to order it to be made The Art of Pottery Pag. 27 28. See the 18. of our New Physico-Mechanical Experiments In the defence against Linus Cap. 4 Dr. H. P. An Ingenious man has proposed another way of setling a Standard for Weather-glasses namely by observing the coldness which is requisite to make distill'd water begin to freez But though the accurateness of this way may be as well as the other justly Question'd and cannot often be put in practise even in Winter it self nor without trouble yet it may also be advantagiously made use of when the cold happens to be great enough to freez water Dr. Wren Dr. Goddard Mr. Hook Defence against Linus Cap. the 5th Theatr. Chynic volum 6. Vitrum optimè clausum ne quid exspir are posset in loco ubi quiesceret statui 〈◊〉 sine animi voluptate lice bat in Pleniluniis manifesta inclusi liquoris incrementa observare in Noviluniis vero Decrementa c. They are the words of Paulus Casatus in his Terra Machinis mota Pag. 143. But since the writing of these Praeliminary Discourses the Author of them having consulted by the means of some Ingenious friends the learned Casatus finds that He never made nor saw the Experiment himself but relates it upon the authority of a certain Dutchman whose name he adds not and who therefore may probably be the same Orthelius that is mention'd by the Author of these Praeliminary Discourses who thinks it requisite to give the Reader this Advertisement because Casatus himself did not as he should have done intimate that he de iver'd this but upon anothers credit L' Hydrographie du P. Fournier liv 18. Cap. 12. Defence against Linus Cap. 3. Sect. 11. of the same 30. Chap. See more concerning these Weather-glasses in the first of these three Discourses See th 〈…〉 gure 〈…〉 rest 〈…〉 Pag. 58. Olai Magni Gent. Sept. Hist. Lib. 11. Cap. 24. Olaus Magnus in Historia Gentium Septentrionalium lib. 11. cap. 20. 21. Cap. 6. pag. 42. See the Praeliminary Discourses 4. Jan. 15. * See the latter part of the next Title In the Discourse touching the primum frigidum Gulielmus Fabritius Hildanus de Gangr 〈◊〉 Cap. 10. Barthol de usu Nivis pag. 80. Pag. 74. Pag. 79. Barthol de figurâ nivis pag. 79 〈◊〉 de usu Nivis pag. 83. Capt. James's Trav. pag. 76. Barthol de usu Nivis Cap. 12. * Of the usefulness of Experimental Philosophy Purch Lib. 3. cap. 5. Sect. 2. pag. 493. Pag. 73. Pag. 67. Lib. 1. Sect. 〈◊〉 Cap. 5. pag. 122. Nicholaus Zucchius Melchior Cornaeus It froze so sore within the house that the Walls the Roof thereof were frozen two fingers thick with Ice and also in our Cabins where we lay all those three days while we could not go out Gerat de 〈◊〉 in his third Voyage Pag. 64. Feb. 4. 1661. Decemb. 11. 1662. Decemb. Decemb. Decemb. the 17. Barthol de Nivis usu Chap. 6. * In our Hydrostatical Paradoxes Ex nive copiosa glaciata compacta Pag. 14. * Mr. Hudsons Voyage for the discovery of the North-west passage written partly by Mr. Abacuck Pricket * In the Sect about the Temperature of the Air. * New Exp. Physico-mech Exper. 6. †See the forecited place * The Appendix to the Physico-mechanical Experiments Decemb. the 13. Decemb. 13. Voyage de 〈◊〉 de Perse Liv. V. Pag. 63. Pag. 86. * The breadth was I know not how omitted in the note but as I remember it was about an 8. part of an Inch. Olaus Ma. Gent. Septentr Hist. Lib. 1. Cap. 14. Purchas Lib. 4. Cap. 13. Purchas lib. 4. cap. 13. pag. 813. * Neither hereafter will I marvel though the strait of Weigats be stopped up to the Northeast with such huge mountains of Ice since the Rivers Oby and Jenesce and very many more whose names are not yet known pour out such a quantity thereof that in a manner it is incredible For it cometh to pass in the beginning of the Spring that in places near unto the Sea the Ice through the excessive thickness and multitude thereof doth carry down wood before it And without doubt this is the cause that about the shore of the strait of Weigates so great abundance of floatiug wood is every where seen and whereas in that strait near nnto Nova Zembla it is so extreme Cold it is no marvel if in regard of the narrowness of the strait so huge heaps of Ice are gathered and frozen together that in the end they grow to sixty or at least to fifty fathomes thickness Says the Description of the Countreys of Siberia Samojeda c. extant in Purchas's third part of his Pilgrim Lib. 3. Cap. 7. Pag. 14. Pag. 106. Purchas lib. 4. cap. 18. pag. 837. Pag. 17. Hydrographie du P. G. Fournier liv 9. cap. 29. compar'd with the 22. Chap. of the same Book Olai Mag. lib. 3. cap. 2. pag. 334 * Saepe aliàs his annis fatalibus tam profundè congelavit marina Aqua ut non tantùm plaustra sed integrum exercitum ad aliquot Milliaria Germanica secure vexerit c. Inquit T. Barthol De nivis usu pag. 43. Barthol de nivis usu cap. 6. Glycas apud Fournier liv 9. cap. 19. In the Evening we were inclosed amongst great pieces of Ice as high as our Poop and some of the sharp blew corners of them did reach quite under us Capt. Jam. pag. 6. Olaus lib. 1. cap. 14. Olaus Magnus 〈◊〉 11. Blefkenius in Purch lib. 3. cap. 22. I have seen also the sides lin'd with reeds 〈◊〉 instead of boarding or steening Pag. 101. Pag. 〈◊〉 * In the Sceptical Chymist The Dialogues about heat and flame 〈◊〉 Bernard de Palissey au Traitté du Sel commum De Claves au second Livre das pierres pierreris Cap. 2. Ibid. 〈◊〉 de 〈◊〉 livre 11. cap. 2. * In the Discourses about Antiperistasis the following passages are taken out of a 〈◊〉 narrative consisting of about two sheets of paper of Joh. Baptista Morinus published in the year 1619. and titled Relatio de locis Subterraneis annexed
with our Living Bodies yet I fear they have too much ascribed to them when they are look'd upon as such exact Instruments to measure heat and cold by that we neither can have nor need desire any better For not yet to mention some inconveniences in the contrivance of them which makes them unapplicable to some purposes and less proper in others then Thermoscopes might be made even in divers cases wherein they are presum'd to be unexceptionable their Reports are not to me I confess quite exempt from suspicion For in ordinary Weather-glasses some part of the Liquor being contiguous to the External Air it is subject to be impell'd more or less upwards not only according as heat or cold affects the included Air but according as the incumbent Air happens to be heavier or lighter And though this be a thing not taken Notice of by those that have treated of Weather-glasses yet 〈◊〉 what we have elsewhere manifested concerning the weight and spring of the Air aud what we have probably 〈◊〉 concerning the varying height of the Mercurial Cylinder in the Torrecellian Experiment I see not why It should not much call in Question the Informations we receive from common Weather-glasses in those cases where the height or weight of the Atmosphaerical pillar that presses upon the Water in the Weather-glass is considerably longer or shorter lighter or heavier then is usual For besides the reason of the thing we have Experience on our side I might mention on this Occasion an Experiment I thought on and also attempted last winter to show ev'n upon a Ballance the varying gravity of the Atmosphaere in one and the same place by hanging a small Metalline weight at one End of a pair of Scales so strangely exact that they would turn with far less then the 500. part of a grain and counterpoising it at the other end with a Hermetically seal'd Glass Bubble which being blown as large and as thin as could possibly be procur'd of so small a weight might by its great disproportion in Bulk to the Metalline Body lose more of its weight then That would upon the Ambient Airs growing more heavy But the particular Account of this Attempt belonging to another place the trial ought not to be more then hinted here especially since it may suffice for our present purpose to alledge that having found as we have already in other papers noted that in a Weather-glass where the Water is not fenc'd from the External Air the weight of the Atmosphaere may make it alter considerably between the Top and Bottom even of a Church or Steeple though it appear'd by more certain Thermoscopes that 't was not the differing Temperature of the Air as to Cold and Heat but the differing gravity of the Atmosphaere which being shorter and lighter at the Top press'd less forcibly upon the subjacent Water and the included Air as is more fully made out in the Treatise above related to And having by the intervention of a Learned Acquaintance desir'd to have some Experiments made of the Effect of the Air upon Weather-glasses in deep Pits or Mines where the Atmosphaerical Cylinder is longer and heavier I receiv'd Information that an Ingenious Physician who had the Opportunity of trying what I desir'd had found that in the Bottom of one of those very deep Pits the water in a common Weather glass rose near three Inches higher then at the top in a shank or pipe of about thirty Inches long And this notwithstanding the warmth that is usual in such deep places which seems not any thing near so plausibly referable to any other cause as to the increas'd gravity of the Atmosphaerical Pillar incumbent on the Water that Pillar being heavier at the Bottom then at the Mouth of the Pit by the weight of an aerial Pillar equal in length to the pits perpendicular height or depth But these are not the only Cases wherein the differing gravities of the Atmosphaere may as well as Heat and Cold have an interest in the rising and falling of the Liquor in Common Weather-glasses For though you should not remove them out of one place and though consequently it may seem that the Atmosphaerical Pillar that presses upon the water must be still of the same length yet not to urge that That may alter unknown to us if retaining its length it retain not its gravity we may be easily impos'd upon and take that Ascension or Subsidence of the Liquor for the Effect of a higher or remiss degree of Cold which may either totally or at least in part and in what part we are left to guess be the Effect of the increas'd or lessened weight of the Atmosphaerical Pillar happening either by the copious dispersion of Vapours and other heavy Steams through the Air or upon other Occasions not necessary to be here discours'd of or by the Praecipitation of such vapours by rain or into dew or else by the Removal of the Occasions of the Augmented Gravity or Pressure of the Air. For we have often observ'd great Variations to happen in the height of the Mercurial Cylinder in the Torricellian Experiment upon great rains and fogs and other sudden and considerable mutations of the Incumbent Air. But since I my self thought fit notwithstanding the plausible ratiocination that led me to this Conjecture to examine it by Experience I can scarce doubt but that others may have the like Curiosity that I had And therefore because it may seem a paradox it will not be amiss of many to annex three or four Trials I made to examine the propos'd doctrine especially ours having been the first observations of this kind that for ought we know have been made by any And indeed others could scarce have well made such though they had lighted on the same thoughts for want of such seal'd Weather-glasses to make them with To omit then those that I made with a seal'd Weather-glass and an ordinary one in which the water remains suspended beneath the included Air I shall briefly relate that in a Room unfurnished with a Chimney I kept two Weather-glasses which for more exactness sake I caus'd to be made of a length far greater then ordinary so that the divisions of the one were half inches and those of the other not much less and yet were Numerous The one of these which was furnished with good spirits of Wine was seal'd the other not but this last I caus'd to be so made of the shape represented by the Scheme that the Air being shut up in the lower part of the Instrument not as in common Weather-glasses at the Top the Liquor might as well in this as in the seal'd Weather-glass rise with heat and fall with Cold. In these Thermoscopes where the Ascension and relapse of the Liquors were by reason of the length of the Pipes far more conspicuous then in Vulgar Weather-glasses I observ'd with pleasure that the Hermetical Thermoscope if I may for distinction sake so call
as principally affected by the proper Virtue of the Cold but by the pressure of the Ambient Air as we shall ere long more fully declare And if this be made out then the computation we are considering will be found to be very fallacious for we have elsewhere shown That the strengths requir'd to compress Air are in reciprocal proportion or there abouts to the spaces comprehending the same portion of Air so that if a Cylinder for instance of four Inches of Air be just able to resist a strength or pressure equivalent to 10. pound weight when it comes to be compress'd into two Inches in this case I say an equal force superadded to the former which makes that a double force or equivalent to 20 pound weight will drive up that already comprest Air into half the space that is into one Inch or thereabouts whence it follows that in estimating the condensation of the Air in a Weather-glass we must not only consider how much space it is made to desert but also what proportion that deserted space bears to the whole space it formerly possest and to what degree of density it was reduc'd before the application of the then force and we must remember that the resistence of the included Air is not to be look'd upon as that of a weight which may remain always the same but that of a spring forcibly bent and which is increas'd more and more as it is crowded into less and less Room But these Nicer speculations it would here be somewhat improper to pursue IV. Wherefore I shall proceed to what may seem a Paradox that even the particular Nature of the Liquors imploy'd in Weather-glasses is not altogether to be neglected till we have a better and more determinate Theory of the causes of Cold then I fear we have For though usually it matters not much what Liquor you imploy yet 't is not impossible that in some cases men may slip into mistakes about them for it will not follow that if of two Liquors the one be much the more obnoxious to the higher degree of Cold that of Glaciation the other must be less easily susceptible of the lower degrees of Cold since those that make seal'd Weather-glasses some with water and some with spirit of wine have confessed to me that they find these last nam'd much more apt to receive notable impressions from faint degrees of Cold then those that are furnished but with water and which yet is easily turn'd into Ice by the cold of our Climate which will by no means produce the like effect upon pure spirit of Wine Besides we cannot always safely conclude as Philosophers and Chymists generally do that the more subtile and spirituous Liquors must be the least capable of being congealed that is made to lose its fluidity as oyl and some other substances are wont to be reduc'd to do by the Action of Cold for the Chymical Oyl of Aniseeds distill'd by a Limbeck is so hot and strong a Liquor that a few drops of it conveniently dissolv'd will make a whole Cup of Beer taste as strong and perhaps heat the Body as much as so much Wine and yet this hot and subtile Liquor I have found upon Trial purposely made to be more easily congealable in the sense freshly explain'd by cold then even common water and to continue so several days after a Thaw had resolv'd the common Ice into fluid water again And I know some distill'd Liquors whose component particles are so piercing and so vehemently agitated that the tongue cannot suffer them and they are not perhaps inferior to most Chymical Oyls nor to Aquafortis it self and yet these may be congeal'd by far less degrees of Cold then such as would yet prove ineffectual to freez either the generality of Chymical Oyls or the generality of saline spirits And indeed till we attain to some more determinate Theory of Cold and come to know more touching its causes then we yet do I see not why it should be absurd to suspect that though there be some kind of Bodies which seem fitted to produce Cold indiscriminately in the Bodies they invade or touch yet if the refrigeration of a Body be but the lessening of the wonted or former agitation of its parts from what cause soever that remisness proceeds it seems not impossible but that besides those Bodies or Corpuscles that may be look'd upon as the Catholick Efficients of Cold there may be particular Agents which in reference to this or that particular Body may be call'd frigorifick though they would not so much refrigerate another Body which perhaps would be more easily affected then the former by 〈◊〉 efficients of Cold. For we may observe that Quicksilver may be congeal'd by the Steams of Lead which have not been taken notice of to have any such Effect upon any other fluid Body and yet Quicksilver is not to be depriv'd of its fluidity by such a degree of Cold as would freez not only water but wine And by what we have formerly related upon the credit of that great Traveller the Jesuit Martinius it seems that water it self may in some Regions be so dispos'd by the constitution of the Soyl that 't is susceptible of strange impressions of Cold in proportion to the Effect which that degree of Cold produces there in humane Bodies Besides Opium also of which three or four grains have too oft destroyed the heat of the whole mass of Blood in a mans Body though that be a very hot subtile and spirituous Liquor does not sensibly refrigerate water as far as I could observe with a good seal'd Weather-glass which I put sometimes in a glass of ordinary water and sometimes into a glass of water of the same Temper and as we guess'd of the same Quantity wherein Opium enough to kill very many men was put in thin slices and suffered to dissolve which seems to argue that as differing Liquors have each their peculiar Texture so there may be certain Bodies whose minute particles by their peculiar seize shape and motion may be qualified to hinder or at least lessen the agitation of the particles of the appropriated Liquor into whose pores they insinuate themselves And thereby according to the lately mention'd supposition they may refrigerate that particular Liquor without having the like Effect on other Liquors whose Textures are differing And I might countenance this by adding that as fiery and agitated a spirit as that of wine when well 〈◊〉 is justly thought to be yet I know more liquors then one that being mingled with it will in a trice deprive it of its 〈◊〉 and the like change I have sometimes made in some other liquors also But I must not insist on such matters having mention'd them but only to awaken mens curiosity and circumspection and not to build much upon them which will be easily credited if it be remembred that a little above I my self sufficiently intimated that this Conjecture supposes something about the
Theory of Cold which is not yet sufficiently clear'd Only because the former Experiments show That the various Agitation of the minute parts of a Liquor whereon its Fluidity depends may be hindred or suppressed by the intervention of adventitious 〈◊〉 But do not clearly show That the Liquor by being depriv'd of that Kind of Agitation does actually acquire a Coldness I might subjoyn thus much that by the Addition of a certain substance which for just reasons I must forbear to describe that would scarce sensibly refrigerate common Water I can make a certain and for ought I know one only Liquor that is wont to the touch to be much of the Temper of Water to conceive a considerable degree of Coldness This I say as strange as it may seem I might here subjoyn to countenance the Conjectures I have been delivering and afford some new Corrolaries but for the Reason newly intimated I forbear and the rather because I think it high time to return thither whence the Considerations I have offer'd about Weather-glasses have made me digress I was going then to take notice upon the Occasion offer'd by what I related of the Influence of the Atmosphaeres gravity upon common Weather-glasses of the difference between them and those that are Hermetically seal'd And indeed these are in some things so much more convenient then the others that if I be not mistaken it has already prov'd somewhat serviceable to the Inquisitive that I have directed the making of the first of them that have been blown in England At the Beginning indeed I had difficulty to bring men to believe there would be a rarefaction and condensation of a liquor Hermetically seal'd up because of the School Doctrine touching the impossibility of a vacuum and especially because I had never seen any Experiment of this kind nor met with any that had but after some Trials which my Conjectures led me to make succesfully enough that in Hermetically seal'd Glasses both Air and Water might be alternately rarifi'd and condens'd I found my work much facilitated by the sight of a small seal'd Weather-glass newly brought by an Ingenious Traveller from Florence where it seems some of the Eminent Virtuosi that enobled that fair City had got the start of us in reducing seal'd Glasses into a convenient shape for Thermoscopes But since that the Invention has in England by a dexterous hand that uses to make them for me been improv'd and the Glasses we now use are more conveniently shap'd and more Exact then the Pattern I caused the first to be made by But the filling of these long ones that we now use is a work of more niceness and difficulty then they that have not tried will be apt to imagine and therefore may elsewhere deserve either from our Pen or his that is most vers'd in making them a more particular account of the way of Performing it The advantages of these Weather-glasses being at no hand inconsiderable For the weight or pressure of the Atmosphaere which as we have noted may work very much upon others their being seal'd defends them from And by this Advantage they may be us'd in the highest and in the deepest places with as much certainty as any where else Next whereas in other Thermometers the Liquor is very subject to be spilt in case they be removed from place to place and which is worse though they be not remov'd is subject to be prey'd upon and wasted by the Air whereby informations of such Weather-glasses are rendred in Tract of time somewhat uncertain In seal'd Weather-glasses there is no danger that Liquor should either spill or evaporate And upon the same Account 〈◊〉 have this Advantage that you may safely let them down into the Sea and immerse them in any Liquor you please without excepting the most corrosive to examine their Coldness Not to mention that instead of the courser Liquors used in common Weather-glasses which are some of them not unapt to freez and others unapt enough to comply with the slighter alterations of the Air and instead of the colourless Liquor whether water or no I know not us'd in the Florentine Weather-glass I saw We imploy highly rectifi'd spirit of Wine whose being brought to a lovely red with Cochinele open'd by the most subtile volatile spirit of Urine by which means the included Liquor is not only very conspicuous and secur'd from freezing but so susceptible of even the slighter impressions of external Bodies which would work but faintly on water that 't is pleasant to see how many Inches a mild degree of heat will make the Tincture ascend in the very slender Cylindrical stem of one of these useful Instruments of which we have spoken the more particularly in this place because we shall have frequent occasions to mention them in the following Papers and no body as yet that we know has written any Account of them But though these Weather-glasses be much more to be relied on then those that are commonly in use yet we would have a Philosopher look upon both these and our Sensories but as Instruments to be imployed by his Reason when he makes his Estimates of the Coldness of Bodies And though perhaps it will signifie nothing in the Event yet I see not why it should misbecome a Naturalists Diligence and circumspection to try whether ev'n such weather-glasses ought to be so far allow'd of as to hinder men from looking after any other kind of ways of estimating Cold. For though the sealing of these Weather-glasses protect the included Liquor from the pressure of the Air and keep it from evaporating yet it will not follow from hence that they must be exempt from all the other imperfections which we formerly mention'd to be imputable to Weather-glasses I know not whether you will allow me to add on this occasion that the tincted spirit of Wine and the like may for ought we know be said of any such Liquor being a particular mixture in case it be allow'd possible that the subtile steams of such Bodies as we formerly noted to be frigorifick in respect to some Liquors may insinuate themselves through the pores of Glass as 't is granted that the Effluviums of the Loadstone do readily per-meat It in this Case I say though I willingly allow it not to be likely yet it is not absolutely impossible that some Steams that wander through the Air may be more or less Cold or may more promote or hinder an agitation among the minute parts in reference to It then in reference to other Liquors as we formerly noted that a grain or two of Opium will exceedingly allay the warmth and motion of the whole mass of Blood in a mans Body though ten times that Quantity will not sensibly refrigerate the tenth part of so much water And that this may appear the less extravagant I shall here add some mention of an odd Phaenomenon that as it were by some Fate has occur'd to me since I began the Discourse
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
ingenious modern Naturalists who acknowledging that the Air has a weight which Mr. Hobs also does in effect admit though he make not so good use of it as they do by that explicate the ascension of water in Weather-glasses teaching that the Cold of the Ambient Air making the included Air shrink into far less room then it possest before the water in the subjacent Vessel is by the weight of the incumbent Air which presses on it more forcibly in all the other parts of its surface then it is press'd upon in that included in the shank impell'd up into that part of the shank which was newly deserted by the self-contracting Air. But though this Account be preferable by far to those which we mention'd before it and though it be not only ingenious but as far as it reaches true yet to me I confess it seems not sufficient and therefore I would supply what is defective by taking in the pressure and in some cases the spring of the external Air not only against the surface of water for That the newly mention'd explication likewise does but also against the internal or included Air. For the recited Hypothesis gives indeed a rational account why the water is impell'd into the place deserted by the Air but then supposes that the Air is made to contract it self by cold alone when it makes room for the water that succeeds in its place whereas I am apt to think that both the effects may proceed at least in great part from the same cause and that the pressure of the contiguous and neighbouring Air does according to my Conjecture eminently concur to reduce the cool'd Air shut up in the Weather-glass into a narrower space This it does in common Weather-glasses because the Ambient Air retains the whole pressure it has upon the Account of its weight whereas the internal Air by its refrigeration even when but equal to that of the External Air looses part of the pressure it had upon the account of its now weakned spring But this as I newly intimated is not the sole account upon which the Air may in some sorts of Weather-glasses impel up the water and contribute to the condensation of the Air incumbent on the water For in some circumstances one or two of which we shall produce by and by it may so happen that the rest of the Air that bears upon the water to be rais'd will not be so much refrigerated as the included Air that is to be condens'd and consequently the other Air will have a stronger spring then this last mention'd Air will retain and therefore the former will have a greater pressure then the latter will be able to resist We shall not now examine whether the spring of the Air depend upon the springy structure of each aerial Corpuscle as the spring of wool does upon the Texture of the particular hairs it consists of or upon the agitation of some interfluent subtile matter that in its passage through the aerial particles whirles each of them about or upon both these causes together or upon some other differing from either of them but this seems probable enough that as when Air being seal'd up in a Glass is afterwards well heated though it acquire not any greater dimensions as to sense then it had before yet it has its spring much increased by the Heat as may appear if the seal'd Tip be broken under water by the eruption of Bubbles by the indeavour of the imprison'd Air to expand it self so upon the refrigeration of the Air so seal'd up though the additional spring if I may so speak which the Heat gave it will be lost upon the recess of that Heat or as soon as the effect of that heat is distroy'd yet there will remain in the included Air a considerable spring and sufficient to make it as well fill at least as to sense the cavity of the seal'd Glass as it did when its spring was stronger And proportionably we may conceive that though Cold at least such as we meet with in this climate of ours do make the spring of an included parcel of Air weaker then it was before the refrigeration of that Air yet it may not make it so much weaker but that the aerial Corpuscles may be kept so far extended as not at all or scarce sensibly to quit the room they possest before in case there be not contiguous to them any other Body which by its pressure indeavours to thrust them inwards and so make them desert part of that space which clause I therefore add because that if the case propos'd do happen 't is obvious to conceive that the weakned spring of the Air cannot retain so much force to resist an external pressure as it would have if the Cold had not debilitated it and consequently this cooled Air must yield and suffer it self to be condens'd if it come to be expos'd to a pressure to which it was but equal before its being weakned And such in common Weather-glasses is the pressure that is constantly upon the surface of the water without the Pipe upon the account of the gravity of as much of the Air or Atmosphaere as comes to bear upon it Having thus explain'd our conjecture we will now proceed to the Experiments we made to countenance it as we find them entred in our loose notes In one of which I find what follows We took a Viol capable of containing five or six ounces of water and having fill'd it almost half full with that Liquor we inverted into it a Glass-pipe of about 10. Inches long and much bigger then a large Swans Quill seal'd at one end and at the other fill'd top full with water so that the open Orifice being immers'd under the Vessell'd water of the Viol there remain'd no Air at the Top of the Pipe Then as much of the Orifice of the Viols neck as was not fill'd by the pipe being carefully clos'd with Cement that no Air could get in or out the Viol was plac'd in snow and salt till the vessell'd water began to freez at the Top and Bottom And according to our expectation we found that notwithstanding this great degree of infrigeration of the Air in the Viol the water in the Pipe did not at all descend So that either the Air did not shrink by so great a Cold or the water whether to avoid a vacuum or otherwise did not remove out of the Pipe to possess the place deserted by the refrigerated Air. Afterwards we endeavoured to repeat the Experiment with the same Glasses but having had occasion to be absent a little too long though not very long we found at our return the upper and seal'd part of the pipe beaten out which we suppos'd to have been done by the intumescence of the water in the Viol upon its glaciation Wherefore we fastned into the same Viol another Pipe some Inches longer then the former and drawn very slender at the seal'd end that it might
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
or Downwards 1. THough after the consideration of the sphere of Activity of Cold it would be the most proper place to take some Notice of the Direction of its Activity yet because one of the Experiments that belong to This head is of great use to facilitate the trial of many of those that follow throughout this whole Collection we will no longer delay to say something of this matter namely in what Line or if you please towards what part the frigefactive vertue of cold Bodies does operate the furthest and the most strongly 2. 'T is a Known Doctrine among Philosophers that the Diffusion of Heat tends chiefly upwards as the flame of a Candle will burn many things held over it at a greater Distance then it would considerably warm them at in case they were held beneath its level or even by its sides and 't is true that in all cases vulgarly taken notice of the observation for reasons elsewhere discoursed of holds well enough and therefore it may be worth enquiry whether in Cold which is generally looked upon as the contrary Quality to Heat the diffusion from cold bodies be made more strongly downwards then either upwards or towards the sides About this matter I can as yet find among my Notes but the two following Experiments 〈◊〉 those not both together A very thin bubble was blown at a Lamp and purposely made flat at the bottom that it might be the more exposed to the cold and it was suspended by a string within a pretty deal less then an inch of a mixture of beaten Ice and Salt wherewith we had half fill'd a conveniently large wide-mouth'd glass but we could not find that a cold Capable of freezing did strike so high upwards for the water in the bubble remained altogether unfrozen which agrees very well with what we have observed that a mixture of ice and salt did not 〈◊〉 the vapours that wandered through the Air above half a barley corns breadth higher then the mixture in the Glass reached 3. A mixture of snow and salt being put into a vial with a long neck the round part of it was by a weight kept under water out of which being taken after a while the outside of the glass beneath the surface of the water was cased with solid Ice N B. especially about the bottom of the vial of greater hardness and thickness then one could easily imagine 4. Thus far the notes from which nevertheless I will not positively conclude though they seem to perswade it that the tendency of the cold produced by Bodies qualified to freez others is greater downwards then upwards For the satisfactory determination of that matter may for ought I know require Trials more artificial and nice then those we have been reciting And I could wish that I could find the last of them to have been carefully repeated and registred because it seems somewhat strange that the Ice should be much thicker at the bottom of the vial then elsewhere in regard that when we have as we very frequently have put mixtures of snow and salt into vials and left them in the open Air we generally observ'd that the outside of the Glass was cas'd with Ice or covered with hoar frost directly over against that part of the inside of the Glass wherein the frigorifick mixture was So that part of the snow and salt resolving one another and falling down in the form of a liquor to the bottom the unmelted part of the mixture would float upon this liquor and the external Ice would appear over against the floating mixture by which it was generated So that as the mixture grew thinner and thinner so would the Zone or girdle if I may so call it of external Ice grow narrower and narrower till at length when the snow was quite melted away the external Ice would quickly also vanish But from this observation which we frequently made That as in such vials 〈◊〉 Ice did not appear as I just now related above half a corns breadth higher then the mixture in the glass so I remember not to have observed it much lower beneath the mixture from those things I say it may be probably conjectured that even the coldest Bodies at least unless their Bulk alter the case do not diffuse their freezing vertue either upwards or downwards to any considerable distance 5. These trials as I was intimating may suggest some difficulties about the last of the two Experiments transcribed out of my notes But as 't is evident these observations were made in the open Air by the freezing of its roving vapours and the mentioned Experiment was made under water so how much this difference of mediums may alter the case as to the way of the Diffusion of cold I dare not till further trial boldly determine especially since one Circumstance to be under the next Title mentioned about the freezing of Eggs may pass for an addirional Experiment as to our present Enquiry For the Cases obtain'd by frozen Eggs suspended under water which seem to argue that the Diffusion of their cold was made every way since they were quite enclosed in the Ice they had produced 6. Though the Experiment of freezing water by the Intervention of salt and snow be not a new one for substance yet I hold it not amiss to make a further mention of it on this occasion Because that what I am to deliver about it is a Paticular not taken notice of that I know of by others the premising of which will according to what we lately intimated much facilitate the trial of many of the Experiments to be set down in the following part of these papers and will indeed appear to be of no small moment in our whole Attempt of Framing an History of Cold. For it has long seemed to me one of the chief things that has hindered men from making any considerable progress in this matter that whereas glass-vessels are generally much the most proper to freez liquors in because their transparency allows us to see what changes the Cold makes in the liquors exposed to it the way of freezing with salt and snow as it has been hitherto used does almost as little as the common way of barely exposing vessels to the cold Air in frosty weather prevent the unseasonable breaking of the glasses For in both these ways the water or other liquor usually beginning to freez at the top and it being the Nature of Glaciation as we shall see anon to distend the water and Aqueous liquors it hardens it is usually and naturally consequent that when the upper crust of Ice is grown thick and by reason of the Expansion of the frozen liquor bears hard with its edges against the sides of the glass contiguous to it the included Liquor that is by degrees successively turned into Ice requiring more Room then before and forcibly endeavouring to Expand it self every way finds it less difficult to burst the glass then lift up the Ice and
consequently does the former and thereby spoils the Experiment before it be come to perfection or have let us see what Nature would have done if she had not been thus hindred in her work 7. The consideration of this invited me to alter the common way of freezing and order the matter so that whensoever I pleased the exposed liquor should not begin to freez at the top or sides but at the bottom which I concluded it very easie to do by mingling the salt with that part only of the snow which was to lye beneath and about the bottom of the glass I placed in it For by this means the snow that was contiguous to the sides was able but to cool the water and dispose it to Glaciation whereas the mingled snow and salt on which the bottom of the glass rested did actually turn the neighbouring Liquor into Ice and lift up the incumbent liquor toward the higher and empty parts of the glass And this liquor also I could afterwards freez at pleasure without danger of breaking the vessel only by so applying salt and snow to the sides of the glass that they never reached except perhaps at the very conclusion of the Experiment so high by a reasonable distance as the upper surface of the liquor in the glass so that the superior parts of that liquor were always kept fluid and capable of being easily impell'd higher and higher by the Expansion of the freezing parts of the subjacent liquor 8. The Speculative inference that may be drawn from this Experiment of making water begin to freez at the bottom not the top will be more properly taken notice of in another place In the mean time I shall only intimate by the way that there is no great necessity of any nice proportion of salt to snow nor of any exquisite mixture of them a third or fourth part or thereabouts of Sea salt in reference to the snow will not do amiss nor do I usually put salt to all the snow at once unless in some case wherein I have a mind to freez a liquor quickly and make a speedy resolution of the snow and salt in order thereunto to which I shall only add that by the way above mentioned I do upon particular occasions make the exposed liquor freez not at the bottom or the top but next to what side of the Glass I please according to the Exigency of the Experiment But though it may suffice to have hinted the Speculative Inference that may be drawn from this way of freezing Liquors it will be expedient to give explicitely this practical Advertisement concerning it that whereas it seems to have been taken for granted that snow is necessary in this Artifice and we our selves were for some time led away with the rest by that supposition yet that is but a presumption and ought to be removed as one very prejudicial to those that with us design the prosecuting Experiments in order to the History of Cold. For snow is but seldom to be found on the ground in comparison of Ice and being but a Congeries of many small Icesicles with much Air intercepted among them it is not 〈◊〉 paribus near so durable as the more intire Body of solid Ice and yet we have found by frequent Experience that Ice well beaten in a Mortar will serve our turn for Artificial Glaciations as well if not in some respects better as snow and therefore in this History of Cold we indifferently prescribe Snow and Salt or Salt and Ice as the Ingredients of our Glaciating Mixtures Title VI. Experiments and Observations touching the Preservation and Destruction of Eggs Apples and other Bodies by Cold. 1. IT is a Tradition common enough though not here in England yet among those that have given us Accounts of very cold 〈◊〉 that if Eggs or Apples being frozen be thawed near the fire they will be thereby spoiled but if they be immersed in cold water the internal cold will be drawn out as they suppose by the external and the frozen Bodies will be harmlefly though not so quickly thawed This Tradition I thought fit to examine not only because it may be doubted whether it will succeed in our more Temperate Climate and because I love not to relye upon Traditions when I have the opportunity to examine them especially if no one Credible Author affirms them upon his particular knowledge but also because I thought the Experiment if true might be so varied and made use of as to become luciferous enough and afford us divers Phaenomena of cold not so easie to be produced by the more known ways of experimenting And accordingly having exposed some of these Bodies to a cold that was judged sharp enough we afterwards put them in water but found not the event answer our expectations no Ice appearing to be generated nevertheless we were not hereby so discouraged as not to repeat the Experiment which we judged to be not unlikely with more sollicitousness and advantage then before and having thereby brought it to succeed we afterwards made several trials of it with several distinct aims but 〈◊〉 now find any Entry of divers of them But those I have hitherto met with among my Notes I shall subjoyn as having in them some Particulars that may afford useful hints to an Enquirer into the History and Nature of Cold. And I shall set down together and that in this place though it would not otherwise be the most proper those I have met with because some Circumstances of one or other of them may be of use to us on several occasions in the present Treatise 2. An Egg weighing twelve drachms and one grain wrapt in a wax'd paper to keep it from the liquor of the thawing snow and frozen with snow and salt wanted four grains of that weight put into a dish of fair water there crusted as much Ice about the outside as made the Egg and Ice fifteen drachms and nine grains the ice being taken off from the shell and the shell very well dried the Egg was found to weigh twelve drachms and twelve grains the Egg being broken was found almost quite thawed the Egg frozen swam in water being thawed it sunk 3. We took two Eggs strongly frozen and in a room where there was a good fire we put one of them into a deep woodden-dish full of very cold water and set the other by it upon a table about two yards from the fire that they might be in Air of the same temper as to heat and cold then perceiving the Egg that lay under water to have obtained a thick crust of Ice we took it out and having first freed it from the Ice broke it and found that some part of the white was not yet freed from a pretty store of little parcels of Ice but the rest of the white which was much the greater part and the Yelk seemed to be much what of the same consistence as if the Egg had not formerly been
frozen whereas the other Egg that lay by upon the dry table had not only its whole white frozen into a consistent Body but the Yelk it self though we saw no distinct particles of Ice in it was grown so hard that it cut just like the Yelk of an Egg over boiled and being cut quite through shewed us certain concentrical circles of somewhat differing Colours with a speck much whiter then any of them in the middle of the Yelk which last circumstances whether they were accidental or no further observation must determine Note that though we have not found above once that frozen Eggs would swim yet when we had broken such Eggs the frozen white would swim but not the yelk 4. We afterwards repeated the Experiment of laying two frozen Eggs near together in the place above mentioned the one under water and the other out of it till that put in water had got a thick Icy crust and by breaking of them both presently after one another were confirmed in the Perswasion that frozen Eggs will thaw by great odds caeteris paribus faster when immersed in water then when surrounded only with Air. 5. We likewise took a frozen Egg and from a fix'd place suspended it so by a slender packthread that it hung quite under water without yet touching the vessel that the water was in This we did partly upon another Design and partly to observe whether or no the Ice would in this case be considerably thicker or thinner against the lower parts of the Egg as we formerly mention'd our selves to have observed it to be very manifestly at the lower parts of a glass which having Ice and Salt in it was immersed under water but when we took out the Egg after we saw that its Icy case had covered the packthread it was hung by we found the case upon breaking it of a thickness uniform enough to keep us from concluding any thing from this trial since though there were a pretty deal of Ice generated at so small a distance from the case of the Egg that it seemed to owe its Production to the same cause yet which was somewhat odd we did not find that this Ice stuck to that which did immediately embrace the Egg though we had some faint suspition that the Rudiments of it might have been very early parted from the Egg by some little shaking of the table occasioned by peoples passing to and fro in the room 6. We took some Pippins and exposing them to freez all night and putting them the next morning into a Bason of very cold water though in a warm room they were not long there without being inclosed with cases of Ice of a considerable thickness Where note 1. That that part of a floating Apple that was immersed under water had a very much thicker coat then the other part which remained above it 2. That the extant part seemed likewise to be harder then the immersed 3. That one of these Pippins being purposely left out of the Bason but layed by it seemed upon cutting to be harder and more frozen then those Apples which had been put into the water which scarce seemed to be at all harder then ordinary Pippins that had never been set to freez at least as to those parts of the Apples that were near the rinde and consequently near the Ice 4. That neither frozen Pippins nor frozen Eggs notwithstanding their great power of turning part of the contiguous water into Ice did appear to Us to detain or congeal any of the roving vapors of the Air as Ice or Snow included with Salt in glasses is as we have formerly observed accustomed very remarkably to do 7. We took Eggs and froze them with ice and salt till the shells of them were made to crack then we took them out and put one of them in Milk two of them in a wide Drinking Glass full of Beer and two more in a large Glass wherein we covered them with Sack that was poured in till it reached much higher in the Glass then the Eggs. But none of these trials produc'd as we could perceive one grain of ice And being desirous to see whether the Acid salt of Vinegre or the Cold in a well frozen Egg would have the chief Operation if those two Bodies were put together I found upon Trial that the Saline parts of the Vinegre began to dissolve the Egg-shell as appeared by the much altered Colour of it but the Cold of the ice in the Eggs was not able to freez any part of the water or phlegm of the Vinegre 8. We had also thoughts of trying whether or no pieces of Iron of several shapes and bignesses being for divers days and nights exposed to the freezing Air and afterwards immersed in water would produce any ice as frozen Eggs and Apples do For the Brittleness of the Laths of Stone-Bows in sharp frosts together with other observations elsewhere mention'd seem to argue that to use a popular phrase the Frost does also get into these Bodies And I have been assured by one whom the Trials I had made with Eggs and Apples invited me to consult that a great Cheese he immersed in water in a Cold Countrey was presently covered over with ice But though as I said I had thoughts of making the above mentioned Trials yet for want of a frost sufficiently durable I was not able to effect what I design'd But thus much I tri'd That though I kept good Lumps of Iron and as I remember of other Metalls besides pieces of Glass and a stone or two of a convenient size in snow and salt I know not how much longer then would have suffic'd to make Eggs or Apples or such kind of things fit to produce store of ice in water upon their being thaw'd therein yet we could not find that upon the immersing the several newly nam'd Mineral Bodies there was the least ice produced in the cold water where we kept them covered I must not nevertheless omit to make some mention of that which lately 〈◊〉 to happen at the door of our own Laboratory respecting the North East where some Glasses newly brought from the shop and not imployed lying in a Basket as they poured water into one of them to rince it part of it was presently turned into ice whilest one of my Domesticks held it in his hand who coming presently to show it me I suspected the ice might have come from or rather with the water that was poured into the Glass but upon enquiring was assured of the Contrary 9. But here I must not omit another trial relating to the former Experiments which may seem somewhat odd if its Event prove constantly the same as when we tried it For after these and divers other Experiments made with frozen Eggs and Apples we thought it might be worth the examining whether or no Ice and the Liquors of these Concretes would produce the like effects as Frozen Eggs and Apples and because 't is usually an easier
no pain save that when he came to himself again he felt such a pricking all his Body over as men are wont to find in an Arm or Leg benumm'd by having been long lean'd upon When I ask'd whether the sharpness of the Cold did not work upon the stones he answer'd That as to Flints he could not tell but as to other stones and such as are oftentimes us'd for Building the violence of the Cold made them frequently moulder into Dust. And to satisfie my Curiosity about the Effect of Cold upon Wood he told me that he had very often in the night especially when their keen frosts were unaccompani'd with Snow heard the Trees cleave and crack with very great and sometimes frightful noises and that the outside of the Fir-Trees that were laid upon one another in their Buildings and was expos'd to the Air would do the like and that he had often seen the gaping Clefts sometimes wide enough to put in his fingers which would remain in the Trees and in the Fir-wood till the thaw after which they would pretty well close of themselves Title VII Experiments touching the Expansion of Water and Aqueous Liquors by Freezing 1. THat water and other Liquors are condensed by Cold and so much the more condensed by how much the greater the degree of Cold is that condenses them has been for many ages generally taught by the Schools and taken for granted among men till of late some more speculative then the rest have called it in question upon the account of the levity of Ice since which I have met with two modern writers that have incidentally endeavoured to prove that Ice is water not condensed but rarified by the intumescence of water exposed to freezing in vessels fitly shap'd These Attempts of these learned Men putting me in mind of what I had tried to this purpose when I was scarce more then a Boy invited me to consider that by the usual ways of Glaciation such as these ingenious Men employ'd the Experiment is wont to meet with a Disaster by the breaking of the Glasses which not only makes the Event liable to some objections of theirs that befriend the common Opinion but which is more considerable hinders them from judging what this Expansion of water that is made by freezing may amount to wherefore we will now set down what we have done to ascertain and yet limit the Experiment as also to advance it further 2. Whereas then these two learned Men we have been mentioning do so expose the water to freez that it is turn'd into Ice at the top as soon as elsewhere the inconveniences of which way we have already noted we by freezing the water as we have formerly taught from the bottom upwards can easily preserve our Glasses entire and yet turn the whole contained water into Ice so that if according to this way You so place a Bolthead or a Glass-egg in whose Cavity the water ascends to the height of an inch or thereabouts within the stem or shank in a mixture of Ice or snow and salt as that the water is first turned into ice at the bottom and sides and not till the very last at the top you shall manifestly see that the ice will reach a good way higher in the neck then the fluid water did and that upon a gentle thaw of the ice the water it returns to will rest at the same height in the stem to which it reached before it was exposed to be frozen 3. We have likewise used other ways unspoken of by the lately mentioned writers to evince that water is expanded by being frozen as first that we took a strong earthen vessel of a Cylindrical form and filling it with water to a certain height we exposed it unstopped both to the open Air in frosty nights and to the operation of snow and salt and found that the ice did manifestly reach higher then the water did before it was congealed Besides if a hollow Pipe or Cylinder made of some compact matter be stopped at one end with wax or some things else which it may be more easie to drive out then to burst the Cylinder and if at the other end it be filled with water and that orifice also be stopped after the same manner this Pipe suspended in a sufficiently cold Air will have the included water frozen and by that change if the Experiment have been rightly made the water will upon congelation take up so much more room then it did before that the above mentioned stoppels or at least one of them will be thrust out and there will be produced a rod of Ice a good deal longer then the pipe at each of whose ends or at least at one of them a Cylindrical piece of Ice of a pretty length may be broken off without medling with the Pipe or the ice that fills it Divers other ways of proving the same Truth might be here alledged but that though these were not 〈◊〉 they are sufficient the matter would yet be abundantly confirm'd by divers of the Experiments that will here and there come in more opportunely in the following part of this Treatise 4. But here it will not be altogether impertinent or unseasonable to take notice that not only those School Philosophers who have considered the breaking of well 〈◊〉 Glasses in frosty weather an accident but too frequent in Apothecaries Shops and Laboratories but divers modern Virtuosi are wont to ascribe the Phaenomenon to this that the Cold of the external Air contracting the Air and Liquor within the Ambient Air must break the sides of the Glass to fill that space which being deserted upon the condensation of the included Air the liquor would otherwise leave a vacuum abhorr'd by nature and even those few Moderns that are loath to ascribe this Phaenomenon to Natures abhorrency of a vacuum either not being acquainted with the weight of the Air know not what probable account to give of it or if they acknowledge that weight are wont to ascribe it to that and to the great contraction of the internal Air made by the Cold of the External 5. But as for the Peripateticks the above mentioned Experiments sufficiently evince that in many cases 't is not the shrinking but the Expansion of the liquors contained in the stopt vessels that occasions their bursting and therefore in these cases we need not nor cannot fly to I know not what fuga vacui for an account of the Phaenomenon and whereas it may be objected that even glasses not half full of distill'd waters if they be exactly stopt are often broken by the frost in Apothecaries shops I answer That neither in this case do I see any need of having any recourse either to the fuga vacui or to the weight of the external Air for even here the Expansion of the freezing liquor may serve the turn for in such inartificial glaciations the liquor begins to freez at the top and the ice there
Claret-wine and if thrust down into either of these liquors they nimbly enough emerged 6. Whether or no Chymical oyls though like expressed oyls they shrink with a moderate degree of Cold would by congelation be like them contracted or like Aqueous liquors expanded we could not satisfie our selves by Experiment because we were unable to advance Cold to a degree capable of bringing such oyls to congelation only we had thoughts to make a trial with oyl of Aniseeds distilled with water in a Limbeck in regard that though it be a very subtile liquor and as Chymists call it an Essential oyl and though in the Summer time and at some other seasons if the weather be warm it will remain fluid yet in the Winter when the Air is cold it will if it be well drawn and genuine easily enough lose its fluidity and therefore we thought it might do well to pour some of it in moderate weather into a conveniently shap'd glass and then to freez it externally by the application of Ice and Salt that we might observe whether upon congelation it would shrink or be expanded And accordingly though we were not provided with any Quantity of this oyl yet in weather that was not sharp we did by the help of some Ice which we procur'd when the season made it a Rarity surround a glass pipe fill'd with fluid oyl of Aniseeds and found though the Pipe were but short yet the inclosed substance when it had lost its fluidity had considerably lost of the height which it reached to before 7. And because the Empyreumatical oyls that are driven out of Retorts by somewhat violent fires seem'd to be of a nature differing enough from those Essential oyls as Artists call them which are drawn in Limbecks by the help of water as well as fire And because we observ'd that some of the firmer oyls may be us'd in Physick in much larger Doses then 't is thought safe to give the latter in Conjecturing from hence that probably Empyreumatical oyls may be less hot and so less indispos'd to Congelation we thought fit to make trial no body else in probability having done it whether the Cold in our Climate could be brought to freez these oyls and whether it would expand or condense them wherefore exposing in conveniently shap'd vessels some good oyl of Guajacum that was diaphanous enough though very highly colour'd to the greatest Cold we could produce we attempted but in vain to deprive it of its fluidity All that we were able to effect being to make it very manifestly shrink Title IX Experiments in Consort Touching the Bubbles from which the Levity of Ice is supposed to proceed 1. SInce the first thing that made the Moderns suspect that water is expanded by freezing is the floating of Ice upon water it will not be 〈◊〉 for confirmation of that Argument to take some notice of the 〈◊〉 of Ice in respect of water This is best observed in great Quantities of Ice for whereas in small fragments or plates the Ice though it 〈◊〉 not to the bottom of the water will oftentimes sink so low in it as scarce to leave any part evidently extant above the surface of the water in vast quantities of Ice that extancy is sometimes so conspicuous that Navigators in their Voyages to Island Greenland and other frozen Regions complain of meeting with lumps or rather floating rocks of Ice as high as their main Masts And if we should meet with Cases wherein we might safely suppose the Ice to be as solid as entire pieces of Ice are wont to be with us and not to be made up of icy fragments cemented together with the interception of considerable Cavities filled with Air it would not be difficult for any that understands Hydrostaticks to give a pretty near guess at the height of the Extant part by the help of what we lately observ'd of the Measures of water's Expansion and by the knowledge of the immersed part which supposing that the Ice were of a prismatical figure and floated in an erected posture would in fresh water amount to about eight or nine times the length of the part of the Prisme superior to the surface of the water 2. But because perhaps the great disparity in the degrees of Cold whereby water is in this and in those gelid Climates turn'd into Ice may breed a difference in the expansion of the frozen water and because some other circumstances may be needful to be taken into consideration about the height of floating Ice above water and these will be more properly taken notice of under the following Title I shall only upon this head of the Levity of Ice subjoyn the ensuing transcript of one of our notes concerning That subject We found that pieces of Ice clear and free for ought the Eye could take notice of from bubbles would not be made to sink in spirit of Wine once distilled from Brandy and it floated likewise in strong spirit of Wine drawn from quick Lime but if the spirit of Wine were well warmed such Ice as I mentioned would sink in it though as it grew cold the same Ice would slowly ascend and sometimes remain for a while as if it were suspended without sensibly rising or falling But all this while the Ice thawed apace in the water whereinto it was dissolved did manifestly seem to run down like a stream through the lighter body of the spirit of Wine the Diversity of the Refractions making this easie to be taken notice of yet common water though heated as hot as I could indure to hold the glass in my hand would not let the fragments of the same parcel of Ice sink into it but in oyl of Turpentine and in thrice Rectifi'd spirit of Wine the Ice would sink like a stone 3. That the levity of Ice in respect of water proceeds from the bubbles that are produc'd in it and make the water when congeal'd take up more room then when fluid has scarce been doubted by any that has consider'd the Texture of Ice as well as taken notice of its levity But if this be the true and only reason we may conjecture that there must be great store of bubbles in Ice extremely minute and undiscern'd by the naked Eye For though in very many parcels of Ice the bubbles are as well conspicuous as numerous insomuch that they render the Ice whitish and opacous yet we have observed that other pieces would swim which yet were of an almost crystalline clearness And therefore we thought fit to look upon some clear pieces of Ice in a Microscope and we shall subjoyn the Event because that when we beheld some of this ice in one of our Microscopes which has been counted by several of the curious as good a Magnifier as perhaps any is in the world we could not discover such store of bubbles as it seemed there should appear upon the supposition that the adequate cause of the levity and expansion of frozen water is
the Bubbles wont to abound in Ice be filled with common Air and even this question though it seem but one comprizes two for to resolve it we must determine whether there be any true Air contained in those Cavities and whether in case there be they be adequately filled with that Air by true Air I mean such an invisible fluid as does permanently retain a spring like the common Air. 7. The former of these two Questions I must confess my self not yet resolved about my Experiments having not hitherto succeeded uniformly enough to satisfie so jealous an observer But yet I shall annex our trials not only because the thing has not been that we know of somuch as attempted by others and our ways of Experimenting if they be duly prosecuted seem as promising and hopeful if the Question be reducible to any certain Decision as perhaps will be easily lighted on but because also we have if we mistake not resolved the second Question by shewing that there is but a small part of true Air contained in the Bubbles of Ice whatever Ingenious men that rely upon probable Conjectures without consulting Experience have been pleas'd to believe to the contrary That the bubbles observed in Ice cannot all be filled with the Aerial particles lurking in the water seems evident enough by the expansion of the water and the Quantity of space taken up by those bubbles which how the interspers'd and formerly latitant Air can adequately fill unless the same parcel of Matter could truly 〈◊〉 much more space at one time then at another which I take to be physically impossible I do not yet apprehend But two ways of trial there are which we imployed to shew that the Icy bubbles are nothing near filled with true Air whether Men will have that pre-existent in the water or stollen in from without or generated anew the former of the two ways of trials probably arguing that these bubbles proceed not only for that they may proceed partly we do not at all deny from the Air pre-existent in the water and the latter concluding more generally that but a small part of the icy bubbles are filled with genuine Air. 8. And 1. we were invited to conjecture both that sometimes or in some cases the Air latitant in the water might contribute to generate icy bubbles though it was unable adequately to fill them and again that sometimes or in other cases such bubbles would be almost as numerously generated notwithstanding the recess of far the greatest part of that latitant Air by the three following Experiments taken verbatim out of our Collections I. We took fair water and having kept it in the exhausted Receiver of our Pneumatical Engine for a good while till we perceived it not to send up any more bubbles we presently transferred it into snow and salt where it was long enough before it began to freez and then we observed that the water did not swell near so much as common water is wont to do and the ice seemed to have few or no bubbles worth taking notice of but when I afterwards placed it between my Eye and the vigorous flame of a Candle I could perceive that it was not quite destitute of bubbles though they were extremely small in comparison of those that would probably have appeared in ordinary water Thus far the first Experiment the second follows which was made at another time II. The water that had been freed from the bubbles in the Receiver though it afforded an ice that seem'd to have smaller bubbles yet this ice being thaw'd part of the water was gently poured into a pipe of glass wherein being frozen it swell'd considerably enough above its first level and besides burst the glass being also very opacous by reason of the bubbles The third Experiment was more industriously prosecuted as may appear by this ample Narrative of it transcribed out of our Collections III. We took a small Egg with a pretty long neck and pouring in water till it reach'd an inch within the stem conveyed it into a long slender Cylindrical Receiver provided on purpose to make trials with such tall glasses the Air being by degrees drawn out of the bubbles appeared from time to time greater and greater and when the Receiver was well exhausted the water seemed to boil a longer time then one would have expected and sometimes the bubbles ascended so fast and great that we were in doubt whether the water did not boil over the top of the Pipe the exhausted Receiver was permitted to be so for a good while till the water had discharged it self in bubbles of its Air and then the glass-Egg was removed into a vessel furnished with ice and salt and there left ten or twelve hours that all the water save that in the neck might be throughly frozen and then we found it to have risen a great way above its first height and removing it into an Air temper'd like that wherein the first part of the Experiment was made having left it there in a quiet place for ten or twelve hours to thaw leisurely lest too warm an Air or too much stirring the glass might be an occasion of generating new bubbles in the exterior part of the ice near the glass we saw pretty store of bubbles but when that was thaw'd the rest of the ice appeared of a peculiar and unusual texture having no determinate bubbles that I could easily distinguish but seeming almost like a piece of frosted glass where the Parts that made the Asperity were exceeding thick set but this ice swam in the water whereinto the rest had been dissolved before it was all thawed when there yet remained a lump about the bigness of a small Walnut we reconveyed it into the Receiver to try whether upon the exuction of the Air the ice would be presently melted but the alteration produced was so small if any that we durst not ground any thing upon it The Receiver being exhausted there did at length appear some bubbles in the water but they were not numerous and a hundred of them seem'd not to amount to one of those larger ones the same water had yielded us the first time it was put in in the ice also some small bubbles disclosed themselves which we did not perceive there before wherefore we took out the Egg and found the ice being now thaw'd that the water was subsided to the mark we had made before it was expos'd to congelation if not some very little way beneath it Then we went about to find the Proportion wherein this dispirited water was expanded by glaciation but in pursuing this there hapned a mischance to the glass which kept the Experiment from being so accurate as we designed And therefore though it seemed to us that it amounted to about the twelfth part which is less then that of the undispirited water yet we designed the repetition of the Experiment Only in this we could not be mistaken that the
expansion wrs considerable since the water rose three inches and a half in the stem though the whole water in the Egg and stem too weighed but two ounces and a half 〈◊〉 the vessel had not been unluckily cracked we should have frozen the water once more and then sealing up the glass Hermetically and suffering the ice leisurely to thaw should have inverted it and broken it under water and have proceeded with it as we had done with some other glasses in the formerly mentioned Experiments 9. A little glass Cylinder open only at one end of a convenient length was thrust into a deep and wide mouth'd-glass about half filled with a mixture of Ice and salt but the Cylinder was neither so quite filled that the water should run over nor yet far short of being so that for all the opacous mixture of Ice and Salt we might guess at the freezing of that part of the water that we could not see by the changes appearing in the other Then conveying all into a Receiver that we had in readiness beforehand we quickly pumped out the Air upon which there came both from the upper lower parts of the water great store of Bubbles to the top where most of them brake into the Receiver having found upon trials purposely made that the Engine had continued stanch all the while and perceiving by the intumescence of the superior parts of the water that the other were frozen we let in the external Air and having removed the Receiver and taken out the mixture before the Ice was half melted we found the water as high as the mixture reached to be turn'd into ice which besides some large and conspicuous bubbles had small ones enough to render it opacous and upon the account of this expansion it was that the water did in the free Air continue a good deal higher then the mark it was but level with when the Cylinder was exposed to freez 10. The other way we employ'd to examine what was contained in icy bubbles and which seemed clearly enough to manifest that they are very far from being filled with true and springy Air is intimated in the last clause of the foregoing narrative but will be best understood by the annexed Experiments transcribed just as I find them registred in my Collections and though they be prolix and contain some few Particulars that make not directly for the purpose I alledge them for yet I think not fit to dismember or to epitomize them or otherwise to alter any thing in them partly that the inference I make from them may be the less mistrusted partly because the way of Experimenting being altogether new will be best apprehended by the subjoyned Examples and partly too because those Particulars that relate not directly to the occasion of our mentioning these trials may be useful to illustrate or confirm some thing that is already delivered or is hereafter to be delivered in the present History of Cold. 11. We took this day a glass of the form of an Egg but of double the capacity out of whose obtuse end rose up a long Cylindrical neck capable to receive the end of my little finger and no more this being fill'd with common water till the liquor reached a pretty way within the pipe and the surface of the water being carefully marked on the outside was placed in a vessel wherein ice very grosly beaten was mingled with a convenient Proportion of salt according to our way of Glaciation the Mixture not reaching up to the mark by above an inch The Experiment afforded us these Particulars I. A heedful Eye did not perceive the water sensibly to subside before it began to freez II. The water began to swell and some parts of it next the side or bottom of the glass to freez within a quarter of an hour III. The ascent of the water in the pipe increased so fast that within an hour from the time the glass was put in it did rise 4. inches and 2 9 above the mark afterwards the swelling connutied so that we took it out though a good part of the water remain'd unfrozen it had reach'd five inches and somewhat more then a half above the first Mark. IV. The ice and salt being purposely kept always beneath the surface of the water the lower parts of the water were frozen and never the upper surface V. During all this great Elevation of the water there appeared no bubbles worth taking notice of in the unfrozen parts of the liquor but the ice was very full of them divers of which toward the latter end of the Experiment were very large Bubbles but not all of them round some being about the bigness of hail shot some small like Mustard seed and others again not much inferior to little pease VI. Having taken out the glass when the water was at the highest mark we did upon a certain design pour in as much sallet Oyl as swam about two inches above it and then the glass was nimbly at the flame of a Lamp seal'd up during which time the included water subsided a little but the glass being again put into the ice and salt the Cold quickly restored the water to its former height and there remained about an inch and a half of the seal'd glass unpossessed by the two contain'd liquors VII Then with a good pair of scales we weigh'd the glass-Egg first in the Air and then in the water the better to discern whether any shrinking of the glass interven'd in the case where it hung freely and was left hanging in its Equilibrium with its opposite weight VIII Whilest it thus hung upon the thawing of the ice many bubbles great and small ascended the great ones with a wrigling motion and vanish'd at the top IX As the ice thaw'd the water and oyl descended till the whole ice was return'd to water at which time we observ'd these two remarkable things the one That the Equilibrium remain'd the same the other which was more considerable that the water was subsided again as low as the first mark with which it was level before it began to swell without falling beneath it notwithstanding the recess of such a multitude of Bubbles divers of which were very large X. The glass being inverted the seal'd end which was drawn slender was gently broken under water of which some being impell'd in did sensibly reduce the Air at the opposite end into a narrower room and as one of the spectators observ'd into a much narrower which is consonant enough to reason XI The glass being again inverted and held till it was setled we found that the water drawn in together with the water it found there and the oyl possess'd the same places as appeared by the marks in the Cavity of the Receiver that they did when it was seal'd up XII And lastly having thrown out the oyl and employing where need was a little water of the same kind we had made use of all this while
we found the glass fill'd to the highest mark to weigh 4374. grains when it was fill'd but to the lowest mark 4152. grains and when quite empty'd 1032. So that the water contain'd betwixt the highest and lowest mark and rais'd by the Glaciation was about a fifteenth part of the water set to freez and probably would have amounted to much more if the water had been all frozen 12. A large glass-Egg being taken with a proportionably big stem we poured water into it till it reached about an inch above the bottom of the stem and fastning a mark there we exposed it all night to freez in snow and salt which was so placed as not to reach so high as the bottom of the stem the next day about ten of the clock we found the water risen in the stem about 15. inches above the mark the whole Cylinder of water being fluid by reason of the snows not reaching to it Then upon a design to be elsewhere mentioned we seal'd up the glass by a very slender pipe that had been before purposely drawn out to a pretty distance from the body of the Cylinder that the glass might be seal'd in a trice before the flame of a Candle could sensibly rarifie the Air and after a while we broke off the Apex of this slender pipe in prosecution of our former Design Then suffering the water to swell freely within seven or eight hours it reach'd the very top of the glass a drop or two running over at the slender Orifice thereof so that in all the water ascended about 19. inches above the first mark then we tried by the flame of a candle to seal the glass but by reason of the Rarefaction of some of the water by the Heat into vapours by which some of the other water was from time to time spurted against the flame of the Candle we found it troublesome enough to seal it up the vessel being removed into a warm place till next morning and all the ice in the belly of it for the water in the stem continued fluid being thawed the water subsided not only to its first mark but a little beneath it by reason of that which was thrown out upon occasion of the sealing of the glass but when we came to invert this after the manner above mention'd into a vessel of water to see how much of the space deserted by the thaw'd Ice was fill'd with Air and how much was fill'd with a subtiler substance or empty just then a mischance frustrated our Expectation 13. An Egg about the same bigness with the former was placed to freez in beaten ice and salt and in less then a quarter of an hour it was risen near an inch above the Mark where the surface of the water was at the first and the water in the ball and the joyning of the neck was frozen into Laminae After an hour and a quarter those Laminae that before appeared in the beginning of the neck now disappear'd but the ball seem'd frozen into a white ice and the water in the neck was risen above the first mark four inches and a half There now appear'd abundance of small bubbles continually ascending through the neck which so continu'd all the time after till it was quite thaw'd and the white ice appear'd full of bubbles The Experiment being further pursu'd the water ascended higher and higher till it had reach'd about eight inches above the first mark Then the top of the pipe being with a Lamp drawn out into a very slender Cylinder for the conveniency of sealing up the glass was again put into the ice that the Air heated by the Lamp might cool upon which the water continued swelling till it began to run over at the orifice of the slender pipe which being held by in the flame of a candle was in a trice seal'd up so that the whole glass now appear'd full of water bating an inconsiderable Quantity of rarifi'd Air not amounting to the bigness of half a small Pea that remain'd contiguous to the seal'd part the Egg being brought into a warm room was kept there all night and a good part of the next morning before the ice was quite thaw'd which when it was the water was found subsided to the first mark and which being done the glass was inverted and the seal'd end immers'd a good way under water where being broken the external Air impell'd the water in the Bason into the Cavity of the pipe insomuch that when we took it out which we did as soon as we thought nomore water was impell'd up reinverting the glass we found that the admitted water reach'd seven inches above the first mark and left an inch and a half of the stem before it began to be wire-drawn besides as much of the slender part of the stem as by guess amounted to a quarter of an inch or more so that it seem'd that the Bubbles which made the water swell and appear'd in the 〈◊〉 amounted to an inch and three quarters of Air which consequently seem'd to be for the most part generated by this operation and to seven inches either of a vacuum or some 〈◊〉 substance which by its having no spring to resist the Pressure of the outward Air appear'd not to be Air We could not exactly measure the Quantity of water we had in all and the proportion of it betwixt the marks 〈◊〉 having left the glass in the window to try whether time or Cold would make the admitted water shrink which we did not find it to do the weather was so sharp that beginning as we concluded to 〈◊〉 the water in the stem the increasing ice burst out the belly of the glass into many pieces Another time 14. A seal'd glass being broken under water there was impell'd into the Cylinder ten inches and a little above a half And the mark it should have risen to was eleven inches and a quarter above the first and lowest mark Another time 15. In the same Bolthead wherein the greatest condensation of the Air was tri'd the water was by the Cold made to swell very near a foot above the mark it rested at when it began to freez then the glass being 〈◊〉 up the contain'd water was removed and suffered leisurely to thaw and upon the Dissolution of the ice the water fell back to the former mark lastly the glass being inverted the Apex was broken off under water and the water in the stem was by the outward Air pressing upon the water in the Bason with some Impetus and noise driven up into the Cavity of the glass and the glass being seasonably and warily remov'd from the Bason we found there had been impell'd up of the water in the Bason a little more then eleven inches so that there seem'd to be near ⅞ of an inch of Air generated or separated by the former operation Another time 16. In the same glass we made the water to swell about ten inches and
inverting the stem and breaking the Neb under water we found about ten inches of water to have been impell'd into the stem so that in this there seem'd no generation of Air. 17. To all these Experiments we shall subjoyn in two words that as in water so in some aqueous liquors we found that the icy Bubbles were not fill'd with Air though we did not think fit to take the pains to measure their respective Expansions by being congeal'd For in that elsewhere mention'd Experiment where we expos'd Milk Urine and Rhenish-wine to freez when all those liquors were risen above their former marks as is there related our Notes inform us that the Experiment was thus prosecuted 18. Being seal'd up the foregoing words mention'd the above-named expanded liquors and suffer'd to thaw the several liquors subsided to their first marks or thereabouts and the glasses being inverted and broken under water we were by an accident hindred from observing what we desir'd in that which had the Wine though when it was taken out of the freezing pot it had ice but not much swimming in it But into the glass that had the Milk the water was manifestly impell'd by the outward Air and so it was into the glass that had the Urine which being remov'd from the Bason and reinverted appear'd to have as much new liquor in its stem as amounted by guess to five or six inches 19. To which Experiment we may add that another time a seal'd glass of partly frozen Claret-wine being broken under water the water was impell'd up between half an inch and an inch above the mark beyond which it would not have ascended if the bubbles had been full of true and permanent Air. 20. If it be said that though I have delivered too many Particulars about so empty and slight a Theme as Bubbles I have this to answer that possibly all these Experiments have rather shew'd us what it is not that fills them then what it is so that more then all these Experiments appearing requisite to clear up the Difficulties about them I shall not think I have altogether mis-spent my time especially if so many past Experiments both new and not altogether impertinent by their not having taught us enough about so despicable a subject as a Bubble shall as they justly may teach us Humility Title X. Experiments about the Measure of the Expansion and the Contraction of Liquors by Cold. 1. TO the Experiments mention'd in the Seventh and Ninth Titles which shew that water has an Expansion it will be proper to subjoyn some of those whereby we endeavoured to measure that Expansion And here we shall not content our selves to say that whereas the Authors we had formerly occasion to point at take notice of their having raised water in a Bolthead half an inch or an inch by freezing we have made it ascend a foot and a half and more This I say we shall pass by because that though by such Experiments we have very clearly and undeniably manifested the Expansion of the water yet unless the Capacity of the vessel be known they will signifie but little towards the determining the Quantity of that Expansion which yet is the thing we are now enquiring after wherefore we shall add that we employ'd two differing ways to measure this Expansion 2. The one was by putting in by weight such a number of ounces of water into a Bolthead till the water was risen a pretty way in the long stem wherewith it was filled then marking on the outside to what height every freshly added ounce of water reach'd in the stem we afterwards poured out a convenient Quantity of the liquor yet leaving enough to fill the whole cavity of the spherical or obtuse end of the vessel and of the lower part of the stem then leisurely freezing this remaining water from the bottom upwards we observed that when it was frozen the ice that was made of 82. parts of water filled as one of our Notes inform us the space of 91. and if I mistake not the Character an eight so that by this troublesome way of Examination we found that the water by the Expansion it received from Cold was made to possess about a ninth part more space then it did before congelation 3. In another of our notes we find as follows 55 parts of water extended themselves by freezing into sixty and a half about six of those parts remaining unfrozen so that in this Experiment the waters Expansion was not much though somewhat differing from what it was in that last mention'd 4. The other way we made use of to measure the Dimensions that water gains by freezing was to take a Cylindrical pipe of glass seal'd at one end and left open at the other at which we fill'd it with water to a certain height that we took notice of by a mark appli'd to the outside and then keeping it in an erected posture and freezing it from the bottom upwards we found that it had acquir'd by a tenth part or thereabouts greater Dimensions in the form of ice then it possessed in the form of water But the nature of the particular parcel of liquor exposed to the Cold for it is not necessary that all waters should be equally dispos'd to be expanded by freezing and some other circumstances not now to be discoursed of may well beget some little variety in the success of this sort of trials For in one that we made carefully we found the Expansion somewhat greater then that last mentioned as may appear by the following Note which compar'd with what was lately delivered of the trials we made by weight of the water's Expansion may invite us to think that we cannot much err by estimating in general that the room that Ice takes up more then water amounts to about a ninth part of the space possessed by the same water before it was turned into Ice The note we were speaking of is this 5. In a more then ordinarily even Cylindrical glass we exposed some water to freez to measure its Intumescence and found that it expanded its self to about an eighth part or at least a ninth upon glaciation this we tri'd twice and thought that the Intumescence might have been more considerable but that in a Cylinder the freezing did not seem to succeed so well But here we must resolve a difficulty which though ordinary Readers may take no notice of yet may breed a scruple in the minds of those that are acquainted with Hydrostaticks For to such Readers this Account of ours may seem to be contrary to the Experience of Navigators into cold Climates who tell us as we shall have occasion to take notice in due place of vast pieces of Ice as high not only as the Poops of their Ships but as the Masts of them and yet the Depth of these stupendious pieces of Ice seems not at all Answerable to what it may be suppos'd to be in case we compare together the
to be measured so the measurers not knowing how long they may have been on ground for ought I know much of that admir'd height may be attributed to the snows that from time to time fall very plentifully in those frozen Regions and are compacted together either by the Sun whose Beams sometimes begin to thaw it and sometimes by the water of the waves that beat against the Ice and being congeal'd with the snow does as it were cement the parts of it together and sometimes by both of these causes So in the instance alledg'd out of Captain James of pieces of ice that were twice as high as his Top-mast-head it is said also that they were on ground in 40. fathome And in the other Example mention'd out of Bartholinus though there be 40. fathome attributed to the immersed part of the ice yet that measure is not exclusive of a greater for it is said that the ice reach'd downwards above 40. fathome and how much downwards and whether as far as the ground we are left at liberty to guess And in that stupendious piece of Ice recorded in the Nova Zembla voyage to have been in all 52. fathome that is 300. and twelve foot deep though it be granted what they affirm that it was 16. fathome above the water which is almost a third part of the whole depth yet I observe that of this Icy mountain it is said that it lay fast on the ground So that as on the one side it seems probable that the upper part of Islands of ice may be increas'd by snow and as I remember that in that famously inquisitive Navigator Mr. Hudsons voyage for the discovery of the North-west passage 't is related that his company was so well acquainted with the Ice that when Night or foggy or foul weather took them they would seek out the Broadest Islands of Ice and there come to Anchor and run and sport and fill water that stood the Ice in ponds very fresh and good So on the other side we know not how much lower the Dutch-mens Ice and Captain James's would have reach'd into the Sea in case the ground they rested on had not hindred them For though one might probably think that these are the greatest depths that any Hills of Ice have been observ'd to attain that mention'd by the Hollanders reaching 36. fathome beneath the water and that mention'd by Captain James no less then 40. fathome yet I find in Mr. Hudsons Voyage that the English in the Bay that bears his Name met with more then one or two Islands of Ice of a fargreater depth underwater For among other things the Relator has this memorable passage In this Bay where we were thus troubled with Ice we saw many of those mountains of Ice a ground in six or seven score fathome water And if the Sea had been deep enough even these stupendious moles of Ice would probably have sunk much lower and so have lessened the heights of the mountains 11. I know that delivering the measure of the Expansion of water alone I have not said all that may be said about the Expansion of Liquors But because as it has not yet appeared to me that any Liquor is expanded by Cold unless by actual freezing I doubted whether Aqueous Liquors as Wine Milk Urine c. were otherwise expanded by congelation then upon the Account of the water or phlegmatick and in a strict sense congealable part contain'd in them and whether it were worth while for a man in haste to examine their particular Expansions Notwithstanding which I would not discourage any from trying whether or no by the differing Dilatations of Aqueous Liquors some of them of the same and some of them of differing kinds we may be assisted to make any estimate of the differing proportions they contain of phlegm and of more spirituous or useful Ingredients 12. After what has been hitherto delivered concerning the Expansion of Liquors by Cold it may be expected we should say something of the measure of their Contraction by the same Quality But as for water which is the principal Liquor whose Dimensions are to be consider'd I have formerly declar'd that I could seldom or never find its contraction in the Winter season when I tried it to be at all considerable And I shall now add that having for greater certainty procur'd the Experiment to be made by another also in a Bolthead the Account I received of it was that he could scarce discern the water in the stem to fall beneath its station mark'd at the upper part of the pipe when the water in the Ball was so far infrigidated as to begin to freez Though I will not deny that in warmer Climates as Italy or Spain the contraction of the water a little before glaciation begins may be somewhat considerable especially if the Experiment be made in Summer or in case either there or here the water expos'd to freez be put into a vessel very advantageously shap'd or brought out of some warm Chamber or other place where the heat of the Air that surrounded it had rarifi'd it But to examine the measures of Contraction in the several Liquors and with the nice Observations that such a work to be accurately prosecured would require would have taken up much more of my time then I was willing to imploy about a work which I look'd not on as important enough to deserve it And therefore I shall here add nothing to what I have said under the Title of the Degrees of Cold touching the contraction of spirit of Wine and of oyl of Turpentine by the differing degrees of that Quality And as for the condensation of Air the vastest fluid we deal with I did indeed think fit to measure how much Cold condenses it But the account of that Experiment will be more opportunely deliver'd in one of the following Discourses Title XI Experiments touching the Expansive Force of Freezing Water 1. HAving shewn that there is an Expansion made of water and Aqueous Bodies by Congelation let us now examine how strong this Expansion is and the rather because no body has yet that we know of made any particular trials on purpose to make discoveries in this matter so that although some unhappy Accidents have kept our Experiments from being as accurate as we designed and as God assisting we may hereafter make them yet at least we shall shew this Expansion to be more forcible then has hitherto been commonly taken notice of and assist men to make a somewhat less uncertain Estimate of the force of it then they seem to have yet endeavoured to enable themselves to make 2. And 1. we shall mention some Experiments that do in general shew that the Expansion of freezing water is considerably strong We took a new Pewter-bottle capable to contain as we guess'd about half a pint of water and having fill'd it top full with that Liquor we scru'd on the stopple and exposed it during
a very frosty night to the cold Air and the next morning the water appeared to have burst the Bottle though its matter were metalline and though purposely for this trial we had chosen it quite new the crack appeared to be in the very substance of the Pewter This Experiment we repeated and 't was one of those bottles fill'd with Ice that had crack'd it which a Noble Virtuoso would needs make me who should else have scrupled to amuse with such a Triffle so great a Monarch and so great a Virtuoso bring to his Majesty to satisfie him by the wideness of the crack and the Protuberance of the Ice that shewed it self in it that the water had been really expanded by Congelation 3. We also tried whether or no a much smaller Quantity of water would not if frozen have the like Effect and accordingly filling with about an ounce of water a scru'd Pewter box such as many use to keep Treacle Salves in quite new and of a considerable thickness we found that upon the freezing of the included water the vessel was very much burst Afterwards filling a Quart Bottle if I mistake not the capacity with a congealable liquor and tying down the Cork very hard with strong Packthread we found that the frost made the liquor force out the stopple in spite of all the care we had taken to keep it down But afterwards we so well fastned a Cork to the neck of a quart bottle of Glass that it was easier for the congealing liquor to break the vessel then to thrust out the stopple and having for a great many hours expos'd this to an exceeding sharp Air we found at length the bottle burst although it were so thick and strong that we were invited to measure the breadth of the sides and found that the thinnest place where it was broken by the Ice was 3 16 of an inch and the thickest ⅜ that is twice as much 〈◊〉 we also by the help of the frost broke an earthen bottle of strong Flanders metal of which the thinnest part that was broken was equal by measure to the thinnest part of the other 4. But the above mention'd Instances serving only to declare in general that the Expansion of water by Cold is very forcible I thought fit to attempt the reducing of the Matter somewhat nearer an Estimate less remote from being determinate and because the water expos'd to congelation may be probably supposed to be Homogeneous we judg'd that the quantity of it may very much vary its degree of Force and because some may suspect that the Figure also may not be inconsiderable in this matter we thought fit to make our Trials in a Brass vessel whose Cavity was Cylindrical and which to make it stronger had an orifice but at one of its ends and whose thickness was such that we had reason to expect that whilest the top remained covered but with a reasonable weight the included water would find it more easie to lift up that weight then break the sides To this Cylinder we fitted a cover of the same mettal that was flat and went a little way into the Cavity leaning also upon the edges of the sides for the more closer stopping of the orifice the cavity of this Cylinder was in length about five inches and in breadth about an inch and three quarters This Cylinder being fill'd top full with water and the cover being carefully put on was fastned into an Iron frame that held it erected and allowed us to place an iron weight amounting to 56. pound or half a hundred of common English weight which circumstance I mention because the common hundred that our Carriers c. use exceeds five score by twelve But this vessel being exposed in a frosty night to the cold Air the contain'd water did not the next morning appear to be frozen and the trial was another time that way repeated with no better success as if either the thickness or clearness of the mettal had broken the violence of the external Airs frigefactive Power or the weight that oppressed the Cover had hindred that Expansion of the water which is wont to accompany its Glaciation Wherefore we thought it requisite to apply to the outside of the vessel a mixture of salt with ice or snow as that which we had observed to introduce a higher degree of Cold then the Air alone even in very frosty nights and though this way it self the glaciation proceeded very slowly and sometimes scarce at all yet at length we found that the water was by this means brought so far to freez that on the morrow the ice had on one side swelled above the top of the Cylinder and by lifting the cover on that side had thrown down the incumbent weight but in this trial the cover having been uniformly or every where lifted up above the upper orifice of the Cylinder we repeated the Experiment divers times as we could get opportunity sometimes with success and sometimes without it and of one of the chief of our Experiments of this sort we find the following account among our Collections 5. The hollow brass weight being about one inch and thee quarters in Diameter and the brass cover put on was loaded with a weight of 56. pound upon the cover and expos'd to an excessively sharp night the next morning the cover and the weight were found visibly lifted up though not above that we could discern a small Barley-corns breadth but the thickness of the brass cover was not here estimated which was much less then half an inch which according to former observations one might exspect to see the ice ascend But that which we took particular notice of was that the inclosed Cylinder of ice being by a gentle thaw of the superficial parts taken out appear'd so full of bubbles as to be thereby made opacous Also when in the morning the Cylinder was brought into my Chamber before the fire was made the 56. pound weight being newly taken off at a little hole that seemed to be between the edge of the Brass and Ice there came out a great many drops of water dilated into numerous bubbles and reduced into a kind of sroth as if upon the removal of the oppressing weight the bubbles of the water had got liberty to expand themselves but this lasted but a very little 6. After this the difficulty we have often met with in the placing of great weights conveniently upon the cover of a Cylinder and the Expectation we had to find the Quantity of the water we made use of capable upon its Congelation to lift up a much greater weight invited us to make trial of its Expansive force by some what a differing way which was to fit a wooden plug to the Cavity of the Cylinder after we had suffered it to soak a convenient time in water that swelling as much as it would before it might be made to swell no more by the water which would lye contiguous
to it in the vessel and then to drive it forcibly in till by considerable weights appended to the extant part of the plug when the Cylinder was inverted we could not draw it out the success of one of these Trials is thus set down in our Collections 7. A Plug was driven into the Cavity of a Brass Cylinder first filled with water the Plug being also well soaked then the Cylinder being inverted the Plug took up half a hundred and a quarter of a hundred weight and would possibly have taken up much more and being exposed to a very sharp night the freezing water thrust out the plug about a barley-corns breadth quite round above the upper edge of the Cylinder and it freezing all that day and the next night it was again exposed the plug not being yet taken out and then the plug was beaten out a little more namely in all near a quarter of an inch 8. Thus we see that the expansive endeavour of the water forced a resistence at least equal to that which would have been made by a weight of 74. pound and probably as the note intimates would have appear'd able to do more if we had had convenient weights and Instruments wherewith to have measur'd the strength of the waters endeavour outwards which some subsequent Trials made us think very considerable though not finding their Events set down in our notes we think it fit at present to leave them unmentioned But one thing there is in these trials that I think not unworthy a Philosophers notice and his considering namely that this endeavour of the water to expand it self is thus vigorous though the uttermost term to which it would expand it self in case it were not at all resisted would be but to about a ninth or at most an eight part of the space it possest before it began to freez whereas Air may by Heat which yet we have elsewhere shewn will not reduce it to any thing near its utmost expansion be brought to possess though not to fill according to the diligent Mersennus's observation seventy times the Dimensions it had before Rarefaction and consequently the Air expanded by Heat does by its endeavours tend to acquire above 60. times the space that the water does when expanded by so high a degree of Cold as is capable to turn it all into Ice not to mention that the expansion to which the Air tends upon the Account of its own spring is as we shew in another place many times greater then that to which Mersennus could bring it upon the bare Account of Heat 9. There remains yet one way whereby we hop'd though not to measure the Expansive force of freezing water yet to manifest it to be prodigiously great or in case we fail'd of this aim to produce at least some other Phaenomena relating to Cold that would not be inconsiderable And though our endeavours succeeded not yet because a happier opportunity may bring them to be one way or other succesful we shall annex That we caus'd to be made an Iron Ball of between two and three inches in Diameter which Ball was solid save that in the midst there was a small Cavity left to place a little water in together with a female screw as they call it reaching from the outward surface of that internal cavity and to this was applied a strong Iron screw so fitted to the internal cavity of the other screw as to fill it with as much exactness as could be obtained And this screw was made to go so hard that it requir'd to be screw'd in by the help of a Vice that it might not be forc'd out without breaking the Iron it self Our design in imploying this Instrument was that having well fill'd the internal cavity with water and forc'd in the screw as far as it could be made to go the Instrument thus charg'd with water might be expos'd to the highest degree of Cold we could produce For having thus ordered the matter we thought we might expect either that the water how much soever we heightned and lengthned the Cold would not freez at all being hindred from the Expansion belonging to Ice in comparison of water or if it did freez that one of these two things would happen either that the expansive force of that little water would by forcing such an Iron Instrument manifest its strength to be stupendious or by not breaking it present us with ice without Bubbles or at least not rarer and lighter then the water it was made of but for want of a sufficient Cold our designs succeeded not so as to satisfie us though we more then once attempted it For the great thickness of the Iron being consider'd we were not sure that the waters not freezing might not proceed rather from the thickness and compactness of the metal then from its resistence to the expansion of water And therefore we must suspend the inferences this Experiment may afford us till we have opportunity to make trial of it with a Cold not only very intense but durable enough the want of which last circumstance keeps us from daring to build any thing on our Experiment 10. And here we may take notice that it may be an inquiry more worthy a Philosopher then easie for him whence this prodigious force we have observ'd in water expanded by glaciation should proceed For if Cold be but as the Cartesians would have a privation of Heat though by the recess of that Ethereal substance which agitated the little Eel-like particles of the water and thereby made them compose a fluid body it may easily enough be conceiv'd that they should remain rigid in the Postures wherein the Ethereal substance quitted them and thereby compose an unfluid Body like Ice yet how these little Eels should by that recess acquire as strong an endeavour outwards as if they were so many little springs and expand themselves too with so stupendious a force is that which does not so readily appear And on the other side in the Epicurean way of explicating Cold though the Phaenomenon seems some what less difficult yet it is not at all easie to be salv'd For though granting the Ingress of swarms of Cold Corpuscles the Body of water may be suppos'd to be thereby much swell'd and expanded yet besides that these Corpuscles stealing insensibly into the Liquors they insinuate themselves into without any shew of boisterousness or violence 't is not so easie to conceive how they should display so strange a force against the sides of those strong vessels that they break when they may as freely permeat or enter them besides this I say we observe that in Oyl which requires a far greater degree of Cold to be congeal'd to a good degree of hardness the swarms of frigorifick Atoms that invade it are so far from making it take up more room then before that they reduce it into less as may appear by those former Experiments which manifested that
Cold does not expand either oyl or uncongealable Liquors but condense them 11. After what I have thus largely delivered concerning the expansive endeavour of freezing water I hope I may be allow'd to leave to others if they shall think it worth the labour the prosecution of the like Experiments upon Wine Milk Urine and other Liquors abounding with Aqueous parts concerning which we shall only in general remind those that may have forgotten it That by some of our Experiments it appears that such Aqueous Liquors are expanded by congelation and that their endeavour outwards is considerably forcible seems more then likely from what we formerly noted out of the Dutch Voyage to Nova Zembla where 't is related that by the extreme Cold both some of their other Barrels and some of those that were hooped with Iron were as they speak frozen in pieces that is according to our Conjecture burst together with the Hoops whether of Wood or Iron by the expansive force of the imprison'd Liquors brought to freez 12. To which I shall add that when I asked an Ingenious person whether in Russia where he liv'd a good while Beer and Wine did not when brought to congelation break the vessels they were frozen in He Answered That he had not observed wooden vessels to have been broken by them perhaps because of their yielding but glass and stone Bottles often Title XII Experiments touching a New way of estimating the Expansive force of Congelation and of highly compressing Air without Engines 1. THere is yet another way that I bethought my self of at once to measure the force wherewith freezing water expands it self and to reduce the Air to a greater degree of condensation then I have as yet found it brought to by any unquestionable way of compressing it But whereas by this method to determine exactly the Expansive force of the water it were requisite not only to know the quantity of the water and that of the Air exposed to the Cold but to make the Experiment in vessels conveniently shap'd to measure the Dilatation of the one and the compression of the other our Experiments being made in a place where we were not provided of such glasses we were not able to make our trials so instructive and satisfactory as else we might have done nevertheless we shall not scruple to subjoyn those of them that we find noted down among our Collections allowing our selves to hope that will not be unacceptable or appear impertinent not only upon the account of their novelty but for two other reasons 2. The first because though they do not accurately define the Expansive force of freezing water yet they manifest that it is wonderfully great better perhaps then any Experiment that has been hitherto practised not to say thought of as may appear by comparing what we have delivered in another Treatise of the great force requisite to compress Air considerably with the great compression of Air that has already been this way effected 3. The second because this new way affords us one of condensing the Air much farther then hitherto it has by any method I have heard of been unquestionably reduced I say unquestionably because though the diligent Mersennus and others seem to have conceived himself to have reduced it in the wind-Gun into a very narrow room yet besides that by our Expedient we have compressed it beyond what these Ingenious Men pretend to Besides this I say I have long much questioned whether the way of compressing Air in a wind-Gun which both they and we have imploy'd may safely be relied on for the oyl or some other analogous thing that is wont this way to be imploy'd and the overlooking of several circumstances that are more necessary to be taken into diligent consideration then wont to be so may easily enough occasion no small mistake in assigning so great a degree to the compression of the Air but our Exceptions against this way of measuring it may be more opportunely discours'd of in another place And therefore we will now proceed to take notice that of the two known ways of compressing Air the clearest and most satisfactory seems to be that which is performed in the wind Fountain as 't is commonly called where yet I have seldom if ever seen the Air that I remember by all the violence men could use to syringe in water crowded into so little as the third part of the capacity of the vessel And an ingenious Artificer that makes store of these Fountains being consulted by me about the further compressing of Air in them he deterr'd me from venturing to try it by affirming to me that both he and another skilful Person of my Acquaintance had like to have been spoiled by such attempts for endeavouring to urge the Air beyond a moderate degree of compression it not only burst some Fountains made of Glass but when the Attempt was made in a large but thick vessel made of strong and compact Flanders Earth the same with that of Jugs and stone Bottles the vessel was by the over-bent spring of the Air burst with a horrid noise and the pieces thrown off with that violence that if they had hit him or his Friend that assisted him in the Experiment they might have maimed him if not killed him out right so that the greatest unquestionable Compression of the Air seems to have been that recorded in the Fifth Chapter of our Defence against the learned Linus where nevertheless we could reduce the Air by the weight of a Cylinder of Mercury of about 100. inches which consequently might near countervale a Cylinder of six score foot of water but into a little less then a fourth part of its usual extent but how much further the Air may be compressed by our new purposed way it is now time to shew by the ensuing notes of which we have not omitted any that we could find both that some scruples which might else arise about the way we imployed may be prevented or satisfied and that the way we imployed in practising this method might by some variety of Examples be the better understood 4. We took a large glass-Egg with a Cylindrical stem about the bigness of my middle finger and pouring in water till it reach'd about a fingers breadth higher then the bottom of the stem we set it to freez in snow and salt for some hours with the stop of the stem which was drawn out into a very slender pipe almost at right angles with the stem open and there left it for some hours and the water was risen betwixt six and a half and seven inches This we did in order to another Experiment but then easily and nimbly sealing up the slender pipe above mentioned that the Air in the stem might not be heated we let it continue in the snow sometimes adding fresh for about 24. hours to observe to what degree the water by expanding it self would compress the imprison'd Air. The length of the Cylinder of
be some unheeded flaw or crack of the glass at which the Air had stollen out we drew near the vessel and attentively prying all about it to try if we could discover any ground of our suspition we found as far as the divided list and other circumstances could inform us that the Air supposing none of it to have got away was reduc'd by our Estimate into the 19. part of the space it possess'd before And this our curiosity prov'd not unseasonable for whilest we were narrowly surveying the glass to spy out some flaw in it we were quickly satisfied there had been none by a huge crack made upon the Eruption of the included Air whose spring being by so great a compression made too strong for the glass to resist it did with a great noise break the ball of the glass into many pieces throwing the unfrozen part of the water upon me and also throwing off the stem of the Egg which yet I had the good fortune to recover intire and which I yet keep by me as a rarity 10. Thus far we then proceeded in compressing the Air which being done in vessels Hermetically seal'd where no Air can get in or out seems to me a more unexceptionable way then those that have hitherto been thought of But further we could not then prosecute it for want both of convenient glasses and of ice or snow of which if we were provided and particularly of strong glasses we should little doubt of reducing the Air to a yet more considerable degree of compression 11. We may add on this occasion that we look'd upon the same way as somewhat less unpromising then others that have been hitherto us'd to try the compression of water for though hitherto neither the Experiments of Ingenious Men nor those made by our selves have fully satisfi'd us that water admits any more compression then it may suffer upon the account of the little parcels of Air that is wont to be dispersed among it yet the unsuccesfulness may perhaps for I propose it but as a mere conjecture be imputed to the porousness of the vessels wherein by the ways already practis'd the Experiment must be made whereas in this new way of ours not only the force wherewith the compress'd Air presses upon the water grows at length to be exceeding great and is appli'd not with a sudden Impetus as when a Pewter vessel is knock'd with a Hammer but by slow and regular degrees of increase but the water is kept in a vessel impervious to its subtilest parts so that it may indeed crack the glass but cannot get out at the pores as water compress'd is wont to do at those of metalline vessels The prosecution of this Experiment to bring it to any thing of Accurateness we omitted partly through forgetfulness and Avocations and sometimes for want of conveniency to try it But by the first of the lately mention'd Experiments about the condensation of Air it seems by the strong multitude of Bubbles which upon the breaking of the glass appear'd in the water that had been compress'd betwixt the Air and the 〈◊〉 that those two Bodies had very violently compress'd it and this we are the more apt to believe because that another time when we had seal'd up some Air and water in a glass-Egg and permitted the water to swell by the operation of the Cold but till it had reduc'd the Air included with it to about three quarters of the space it possest before even then I say to try whether the subjacent water were not also compress'd by the Air it urg'd we broke off the seal'd Apex of the glass and perceiv'd as we expected the water to ascend and that to the height of a quarter of an inch as we found by measure But such trials having not been as we just now acknowledg'd duly prosecuted we shall at present content our selves to have nam'd this way of attempting the compression of water without grounding any Inferences upon it Title XIII Experiments and Observations touching the sphere of Activity of Cold. 1. THe sphere of Activity of Cold or to speak plainer the space to whose extremities every way the action of a Cold body is able to reach is a thing very well worth the enquiring after but more difficult to find then at first one would imagine For to be able to assign the determinate limits within which and not beyond them a cold Body can operate several things are to be taken into consideration as first what the degree of Cold is that belongs to the assigned Body For it seems rational to conceive that if a cold Body as such have a diffusive vertue those that have greater degrees of Cold as Ice and Snow will be able to diffuse it to a greater distance as we see that a coal of Fire will cast a sensible heat much further then a piece of wood that is heated without being kindled Secondly the Medium through which the Diffusion is made may help to enlarge the Bounds or straiten the Limits of it as that medium is more or less dispos'd to receive or to transmit the Action of the cold Agent Thirdly Not only the Consistence and Texture of the Medium but its Motion or Rest may be considered in this case For in frosty and snowy weather men observe the winds that come from frozen lands to blow more cold then winds from the same Quarter would do in case there were no Ice nor Snow in their Passage Fourthly There may be made very differing Estimates of the Diffusion of Cold according to the Instrument that is imploy'd to receive and acquaint us with the Action of Cold. For a liquor or other Body may not appear cold to him that examines it with a Weather-glass whilest he shall feel it cold with his hand and as we elsewhere also note to that sensory it self as 't is variously dispos'd the same object will seem more or less cold so much may the Predisposition of the Organ impose upon the unskilful or unwary Fifthly The very bulk of a cold Body may very much inlarge or lessen its sphere of Activity as we may have occasion to shew ere long And besides there may be divers other things that may render it very difficult to ascertain any thing in this matter And therefore I shall reserve them for other opportunities and observe now in general that in such small parcels of Ice it self as in our Experiments we are wont to deal with we have found the sphere of Activity of Cold exceeding narrow not only in comparison of that of heat in fire but in comparison of the Atmosphere if I may so call it of many odorous Bodies as Musk Civet Spices Roses Wormwood Assa dulcis Assa foetida Castoreum Camphire and the like nay and even in comparison of the sphere of Activity of the more vigorous Loadstones insomuch that we have doubted whether the sense could discern a cold Body 〈◊〉 then by immediate Contact 2. And to
he inform'd me that it was their usual way to turn water and snow into ice by pouring a convenient Proportion of that liquor into a great quantity of snow and having also inquir'd 〈◊〉 ice had not the like operation he told 〈◊〉 that t was usual and he had seen it practis'd in 〈◊〉 to cement Ice to Buildings and other things and also to case over Bodies as it were with Ice by gradually throwing water upon them But I doubt whether that Effect be to be ascrib'd barely to the Contiguity of the Ice because I learn'd of him that this way of increasing ice is practis'd in very frosty weather when water thinly spread upon almost any other Body would be frozen by the vehement sharpness of the Air. 7. The Glaciations that nature unguided by Art is wont to make beginning at those parts of Bodies at which they are expos'd to the Air it usually happens that they freez from the upper towards the lower parts But how far in Earth and Water the most considerable Bodies that are subject to be frozen the frost will pierce downwards though for some hints it would afford worth the knowing is not easie to be defin'd because the deepness of the frost may be much varied by the degree of Coldness in the Air by which the Glaciation seems to be produc'd as also by the greater or 〈◊〉 Duration of the frost by the looser or closer texture of the Earth by the nature of the Juices wherewith the Earth is imbu'd and by the constitution of the subjacent and more internal parts of the Earth some of which send up either actually warm or potentially hot and resolving steams such as those that make corrosive liquors in the bowels of the Earth so that the frost will not seiz upon or at least cannot continue over Mines and I have seen good large scopes of land where vast quantities of good Lime-stone lay near the surface of the Earth on which I have been assur'd by the Inhabitants that the snow will not lye There are divers other things that may vary the depth to which the frost can penetrate into the ground I say into the ground because in most cases it will pierce deeper into the water But yet that we may not leave this part of the History of Cold altogether uncontributed to we will add some of our Notes whereby it will appear that in our Climate the 〈◊〉 〈◊〉 〈◊〉 less into the ground then many are pleas'd to think 8. The notes I find about this matter are these that follow which I 〈◊〉 unaltered because 't were tedious and not worth while to add the way we imploy'd and the cautions we us'd in making the observations but we shall rather intimate that the following trials were made in a Village about two miles from a great City I. Jan. 22. After four nights of frost that was taken notice of for very hard we went into an Orchard where the ground was level and not covered with grass and found by digging that the frost had scarce pierc'd into the ground three inches and a half And in a Garden nearer the house we found not the Earth to be frozen more then two inches beneath its surface II. Nine or ten nights successive frost froze the grasless ground in the Garden about six inches and a half or better in depth and the grasless ground in the Orchard where a wall 〈◊〉 it from the south Sun to the 〈◊〉 of about eight inches and a half or better February the 9. we digg'd in an Orchard near a wall that respects the North and found the frost to have 〈◊〉 the ground 〈◊〉 a foot and two inches at least above a foot 〈◊〉 〈◊〉 the eight day since it was 〈◊〉 〈◊〉 inches and a half A slender pipe of glass about 18. inches long and seal'd at one end was thrust over night into a hole purposely made with a Spit straight down into the ground the 〈◊〉 of the water being in the same level with that of the Earth the next morning the Tube being taken out the water appear'd frozen in the whole Capacity of the Cylinder but a little more then three inches But from this stick of ice there reach'd downwards a part of a Cylinder of ice of about six inches in length the rest of the water remain'd 〈◊〉 though it were an exceeding sharp night preceded by a Constitution of the Air that had been very lasting and very bitter The Earth in the Garden where this Trial was made we guess'd to be frozen eight or ten inches deep as it was in another place about the same house But is this Tube had not been in the ground the ambient Air would have frozen it quite through 9. Another Note much of the same import we find in another place of our Collections Finding that by reason of the mildness of our Climate I was scarce to hope for any much deeper Congelation of the Earth or Water I appli'd my self to inquire of an Ingenious Man that had been at Musco whether he had observed any thing there to my present purpose as also to find in Captain James's Voyage whether that inquisitive Navigator had taken notice of any thing that might inform me how far the Cold was able to freeze the Earth or Water in the Island of Charleton where that Quality may probably be supposed to have had as large a sphere of Activity as in almost any part of the habitable world And by my Inquiries I 〈◊〉 that even in frozen Regions themselves a congealing degree of Cold pierces nothing near so deep into the Earth and Sea as one would imagine For the Traveller I spoke with told me that in a Garden in Musco where he took notice of the thing I inquir'd about he found not the ground to be frozen much above two foot deep And in Captain James's Journal the most that I find and that too where he gives an Account of the prodigiously tall ice they had in January concerning the piercing of the frost into the ground is this that The ground at tenfoot deep was frozen Whence by the way we may gather how much sharper Cold may be presum'd to have reigned in that Island then even in Russia And as for the freezing of the water He does in another place occasionally give us this memorable Account of it where He relates the manner of the breaking up the Ice in the frozen Sea that surrounds the Island we have been speaking of It is first to be noted says he that it doth not freez naturally above six foot the rest is by accident such is that Ice that you may see here six fathome thick This we had manifest proof of by our digging the Ice out of the Ship and by digging to our Anchors before the Ice broke up The rest of that account not concerning our present purpose I forbear to annex only taking notice that notwithstanding our lately mention'd Experiment of freezing water in
a glass Tube thrust into the Ground yet it seems that at least where Captain James winter'd the water was not much above half so thick frozen as the Earth But we have already noted the indisposition of salt-water to congelation and whether fresh water would not have been deeper frozen may be justly doubted Title XIV Experiments touching the differing Mediums through which Cold may be diffus'd 1. IN examining whether Cold might be diffus'd through all Mediums indefinitely notwithstanding their Compactness or the Closeness of their Texture we must have a Care not to make our Trials with Mediums of too great thickness least we mistakingly impute that to the Nature of the Medium which is indeed caus'd by the distance which the Medium puts betwixt the Agent and the Patient For the mixtures of Ice and Snow wherewith we made our Experiments will operate but at a very small distance though the Medium resist no more then the common Air as may appear by some of the Experiments recorded in this Treatise This premis'd we may proceed to relate that having plac'd a copious mixture of ice and salt in Pipkins glaz'd within and in white Basons glaz'd both within and without we observ'd that the outside of both those sorts of vessels was crusted over with ice though however the bak'd Earth had not been compact nor the vitrifi'd surfaces of a very close Texture the very thickness of the vessels was so great that it seem'd it would scarce have been able to freez at a greater distance 2. By the Experiments formerly mention'd of freezing water in Pewter bottles it appears that Cold is able to operate through such mettalline vessels 3. And this may be somewhat confirm'd by one of the prettiest Experiments that is to be perform'd by the help of Cold namely the making Icy Cups to drink in The way we us'd was this We caus'd to be made a Cup of Lattin by which I mean Iron reduc'd into thin plates and tinn'd over on both sides of the shape and bigness I intended to have the Cup of then I caus'd to be made of the same matter another Cup of the same shape with the former but every way less so that it would go into the greater and leave a competent interval for water betwixt its convex surface and the concave of the other This innermost Cup was furnished with a rim or lip by which it lean'd upon the greater and by whose help its sides and bottom were easily plac'd at a just and even distance from the sides and bottom of the other but the Distance between the two bottoms is made greater then that between the sides that the icy Cup might stand the firmer and last the longer The interval between the two parts of this Mould being fill'd with water and the Cavity of the internal Cup being fill'd with a mixture of ice and salt partly to freez the contiguous water and thereby cooperate to the quicker making of the Cup and partly by its weight to keep the water from buoying up so light a Cup the external part was surrounded with ice and salt whose Cold so powerfully penetrated to the internal metalline Mould that the water was quickly frozen and the Parts of the Mould being disjoyn'd appeared turn'd into an icy Cup of the bigness and figure design'd And these Cups being easily to be made and of various shapes and that in the midst of Summer if snow or ice be at hand are very pleasant triffles especially in hot weather when they impart a very refreshing coolness to the drink poured into them and though they last not long especially if they be imploy'd to drink Wine and such like spirituous Drinks in yet whilest some are melting others may be provided and so the loss may be easily repair'd all the difficulty we met with was to disjoyn the parts of the Mould which are wont to stick very fast to the ice they include And we tri'd to obviate this sometimes by annointing the inside of the Mould with some unctuous and not offensive matter to hinder the Adhesion of the ice and sometimes by applying some convenient heat both to the convex part of the external and the concave part of the internal piece of the Mould which last mention'd way is quick and sure but lessens the durableness of the Cup. We were lately inform'd that this way of making Cups of Ice is set down 〈◊〉 〈◊〉 Argenis and 't is like enough that 〈◊〉 Man may have learn'd it amongst some of the Virtuosi of Italy he convers'd with But if we that learn'd it from none of them had not been taught it by Experience we should scarce have ventur'd to try it upon the Credit of a Romance that sort of Composures being wont to be fabulous enough to pass but for Poems in Prose 4. The learned and industrious Mathematician Erasmus Bartholinus mentions in his newly publish'd Discourse de Figura 〈◊〉 an Experiment by which he tells us that some Masters of Natures secrets do easily even in the midst of heat reduce water into Air. For they put a little snow or ice into a Funnel and thereby so refrigerate and condense the ambient Air that there will dew trickle down the sides of the Funnel By which means it has been said that some Ingenious Men have hop'd to make an artificial Fountain in the midst of Summer But I here mention this Experiment rather because 't is not unlikely to please those to whom 't is new and because having purposely tri'd it in large and thick funnels of glass it may be pertinently enough deliver'd in this place where we are treating of the Transmission or Propagation of Cold through close and thick Mediums then because we expect to make of it that use especially that Oeconomical use that has been lately intimated For first 't will be very hard to prove that 't is the very Air it self and not rather the vapours swimming in it that are by this means transmuted into water And secondly 't is true indeed that a mixture of snow and salt will condense vapours on the outside of a Funnel but either they that hop'd to make this use of the Experiment have little Experience of it and write conjecturally or else they have made it with a success very differing from ours For though we imploy'd a large Funnel and suspended it by a string artificially enough ti'd about it in the free Air And though the mixture of ice and salt we put in were sufficiently infrigidating as will appear by and by and far more so then ice or snow alone would have been yet that mixture being not able to condense the vaporous Parts of the Air into dew much if at all longer then the mutual Dissolution of the salt and snow lasted the liquor that was this way obtain'd and dropp'd down at the bottom of the Funnel whose internal Perforation ought to be carefully stopp'd least any of the resolved snow and salt should fall through
and spoil the other liquor was indeed sweet like rain water but so very little as well as so slowly generated that it amounted not any thing near to that which the snow imploy'd and spoil'd to make it would have afforded So that it may be question'd whether some cooling liquors which can as well as this mixture condense the vapid Air into water and whose Texture is not destroy'd in this operation as that of the snow is might not be more hopefully imploy'd to obtain water from the Air to which I shall only add this one thing That the mixture of snow and salt did turn the vapours that fasten themselves to the outside of the glass first into Ice before they dropt down in the form of water in almost all our Trials of this nature as well in thick Funnels as in other and thinner glasses 5. That in Hermetically seal'd glasses an included mixture of snow and salt will freez the vapours of the Air on the outside of the glass divers of the Experiments of the present Treatise do manifestly evince which argue that even so extremely close a Medium as Glasses is not able to hinder the Transmission of Cold. And this is not superfluously added because in vessels not Hermetically seal'd it may be pretended that 't is the internal Air that communicates its Coldness by some unheeded but immediate intercourse with the external After this we thought it worth an Experiment to try whether or how Cold would be diffused through a Medium that some would think a Vacuum and which to others would seem much less disposed to assist the Diffusion of Cold then common Air it self to compass this the Expedient we bethought our selves of was to suspend a slender glass full of water in one of the small Receivers belonging to our Pneumatical Engine and when the Air was very carefully pump'd out to bury the exhausted Receiver in a copious and ready prepar'd mixture of Ice and Salt to see whether notwithstanding the withdrawing of the Medium the water suspended in a kind of Vacuum as to Air or gross substances would yet be frozen by the Cold. That Event of our trials which alone I find among my Notes is registred in these terms 6. A small pipe seal'd at one end was at the other fill'd almost with water and was put into a Receiver consisting of a somewhat long and slender Tube of Glass seal'd at one end and inverted upon the Engine plate then the Air was carefully exhausted for the pump was ply'd a while after no Air appear'd to come forth in any bubble out of the Receiver through the external water nor did the water in the small pipe within disclose any number of bubbles worth taking notice of then by the help of an almost Cylindrical plate of Iron beaten Ice and Salt were heap'd against the outside of the Receiver about the height to which the water in the small pipe reach'd And at length though as we all thought much more slowly then such a Congelation would else have been perform'd the water was for the most part frozen in odd kind of flakes from the top to the bottom and the ice seem'd not to have any considerable number of Bubbles 7. There is one Experiment I have made about the Transmission of Cold through indispos'd Mediums which may not be unworthy to be here inserted For I had once a mind to try whether a cold Body could operate through a Medium that was as to touch actually hot and had its heat continually renew'd by a sountain as it were of heat that perpetually diffus'd through it new supplies of warm Liquor so that the cold Body could not here as in other cases first allay the heat of the Medium and then lessen it more and more till it had quite extinguish'd it To compass this I had soon after an opportunity of making some trials presented me For being at the Mineral Springs at Tunbridge to drink those wholsome waters for my healths sake I soon accustomed my self to drink them in considerable Quantities very early in the morning when they were exceeding Cold and sometimes drinking them in bed as well as sometimes at the Springs-head I had the Curiosity to observe whether in case I took them down very fast they would not through the warm Muscles and outward Parts of the Abdomen diffuse a sensible Coldness and upon more Trials then one I found that by laying my warm hands on the outside of my Belly I there felt at least as it seemed to me a manifest and considerable Degree of Coldness And when I related this to some ingenious Persons that were better acquainted with those Springs then I they told me that there was among those many that then resorted to those famous Springs a Knight whose Name I remember not whose Disease being judg'd formidable the Physicians enjoyned him to drink in a morning two or three times the Quantity that afforded me the Observation I was relating and that when this Knight had fill'd his Belly with so much water he us'd mightily to complain of the Coldness it diffus'd through his Abdomen insomuch that he was fain to ply those parts long with hot Napkins clapp'd to them one after another which yet as he complain'd were soon refrigerated by the excessive Cold that the water diffus'd to the outside of his Belly which yet nevertheless was not that I could learn at all prejudic'd no more then mine by so sensible and piercing a Cold. 8. It may be doubted whether in case water be not fluid upon the account of a congenite motion in the Corpuscles it consists of its fluidness may not proceed from the agitation of the ambient Air either immediately contiguous to the surface or communicating its agitation to the water by propagation of its Impulse through the vessel that interposes betwixt them To contribute to the clearing of this and some other things we devis'd the following Experiment We provided a glass-bubble of about the bigness of a Walnut and the form almost of a Pear whose stem was purposely made crooked for the conveniency of suspension This being fill'd with water which is troublesome enough to be done unless one have the knack we hung it at one end of a thread whose other end we past through a Cork by a perforation purposely made into which we afterwards fastned the thread by thrusting in a small peg to rivet it in Then filling a glass not very broad but yet furnished with a mouth wide enough to receive the bubble with oyl of Turpentine such as we bought it at the shops we stopp'd the orifice with the newly mention'd Cork so that the seal'd Bubble hanging at it was covered and every way surrounded by the oyl of Turpentine which being a liquor that at least in such Colds as we here have will not freez we plac'd the glass in beaten Ice and Salt and as it were buri'd it therein and at the end of about three
hours having been diverted by some occasions from taking it sooner out we found as we had conjectured that notwithstanding that the oyl of Turpentine continued perfectly fluid as before yet the Bubble totally immersed in this heating Chymical oyl was frozen throughout not excepting that which was harboured in the little Neck or Stalk and when I came to lift it out of the liquor the glass being crack'd as we supposed by the Cold the string brought up a little part of that which was nearest to it the rest in the form above mentioned staying behind and subsiding And that which was remarkable in this piece of Ice was that when we had taken it out it appeared cleft very deep from the outside almost to the centre according to a line drawn from the slenderest part of it almost as if one should with a knife cut a Pear in two from the stalk downwards according to its whole length And these two pieces were easily enough separable and to adde that circumstance for trial sake we left them divided in the same liquor and vessel with some thawing Ice and Salt about them for 14. or 15. hours without finding them any thing near so much wasted or resolved into water as most would have expected Whilest the above mentioned Bubble was exposed to be frozen we likewise placed by it in another vessel a Glass-Egg whose Ball and a little part of its stem we had fill'd with some of the very same parcel of oyl of Turpentine and placing about the sides of this Egg some ice and salt we observed as we expected that the liquor was after a little while made by the Cold to subside about half an inch so that 't is worth some Philosophers considering why if according to the lately mention'd Atomical doctrine Cold be made by the introduction of swarms of real and extended though Atomical Bodies they should pervade the oyl and contract it without freezing it but freez the water without contracting it but expending it rather 9. A small bubble of the bigness of a very little Nutmeg fill'd with water and Hermetically seal'd up was by a cork and a string suspended in spirit of Wine so as to be surrounded therewith and being exposed to the Air the same night in the stopt glass was the next morning found altogether frozen though the spirit of Wine it self were not at all so But another bubble by the help of a string Cork and piece of Lead carefully suspended in a strong solution of Sea-salt and exposed at the same time in a like vessel with the former when they both came to be look'd upon appear'd to be no more frozen then the brine it self which was not so at all 10. A glass Bubble of the bigness of a small Nutmeg fill'd with water and Hermetically seal'd being immersed by a weight of Lead fastned to it beneath the surface of a very salt Brine but yet not so as to reach the bottom of the liquor or glass was exposed all night to freez in weather that was extraordinarily cold but neither the imprison'd water nor the other appeared to be at all frozen The like Experiment we repeated another frosty night but without freezing either of the liquors But to show the usefulness of repeating Experiments about Cold if there be opportunity and especially in such cases where the degree or some other circumstance may much vary the event we will add that having exposed a Bubble like that newly mention'd and immers'd in spirit of Wine we found the next morning the water in the bubble turn'd into ice and having likewise exposed such a bubble immers'd in very strong Brine to be frozen by a mixture of ice and salt within about two hours after we found the bubble broken as we suppos'd upon the Expansion of the water upon its growing Ice And we also found the upper part of the bubble with the Ice sticking to it and the other part of the glass was crack'd with lines running from a point almost like the Pole and Meridian in a Globe whence we concluded the glass to have been as 't is probable burst asunder upon the Expansion of the fresh water into ice and that the Reason why there remain'd but a comparatively little parcel of ice was probably that the salt water getting in at those crannies or chinks dissolved as much of the new made ice as in a little while it could easily reach Besides 11. We fill'd a glass bubble with fair water and having Hermetically seal'd it we suspended it by a string fastned to the cork in the cavity of a wide mouth'd glass well stopt so that the bubble was every way at a good distance from the sides bottom and top of the glass This we did to try whether a sufficient degree of Cold at that distance would be freely transmitted through the glass without the intervention of a visible liquor and accordingly we found the suspended Bubble crack'd by the ice that fill'd it Title XV. Experiments and Observations touching Ice 1. A Great part of our present History being imploy'd about delivering the Phaenomena of Congelation it is not to be expected that in this Section where we treat of Ice as a distinct part of our Theme we should deliver all those particulars that have occurr'd to us wherein ice is concern'd And therefore we shall restrain our selves to the mention of those that belong to ice considered as it consists of intire and distinct Portions of congeled water Aud though we shall deliver some few Experiments of our own such as we had any opportunity to make yet much the greater part of this Section will fitly enough be taken up by Collections out of Travellers and Navigators into those Colder Regions that afford much considerabler or at least much stranger Observations concerning ice then are to be met with in so temperate a Climate as ours And what we have to deliver in this Section will naturally be divided into two parts the one consisting of our own Experiments 〈◊〉 the other containing some Passages that we have selected out of Voyages or that have been afforded us by the Relations of credible Travellers And of these two sorts of Observables that which has been first mention'd shall be first treated of 2. Some that have been in the East Indies inform us that in some parts of those Countries they were looked upon as great Liars for affirming that in Europe the fluid body of water was often without any artifice or endeavour of Man turned in a few hours into a solid and compact Body such as Ice And certainly if custom did not take away the strangness of it it would to us also appear very wonderful that so great a change of Texture should be so easily and inartificially produced But how solid the Body of ice is or rather how strong is the mutual adhesion of its parts has not yet that we know of been attempted by Experiments to be reduced to some kind of
in the midst of the Sea consists but of the fresh Particles of water that plentifully concur to compose the Sea water yet besides that in case the fresh water were taken as some of that I have found mentioned in Voyages has confessedly been from the top of the ice it might possibly be no more then melted snow which as we elsewhere take notice does in those extremely cold Regions easily freez upon the ice it falls on and oftentimes much increases the height of it Besides this I say the Argument from the insipidness of the resolved ice will conclude but upon supposition that as that ice was found in the Sea so it was also made of the Sea water which though it may have been yet I somewhat doubt whether it were or no since I find some Navigators of the most conversant in the cold Climates to inform us That most of those vast Quantities of ice that are to be met with about Nova Zembla and the strait of Weigats and that choke up some other passages whereby men have attempted to pass into the south Sea are compos'd of the accumulation of numerous pieces of ice cemented together by cold water that are brought down from the great River Oby and others so that it may very well be suppos'd that these mountainous pieces of ice may be some of these which upon the shattering of ice in Bays and straits partly by the heat of the Sun and partly by the Tides may be afterwards by the winds and currents driven all up and down the Seas to parts very distant from the shore and some of these it may be that our Countreymen met with and obtain'd their fresh water from Which I the rather incline to think because that as we shall have occasion to observe in another Section the main Sea it self is seldom or never frozen But my scope in all this is but to propose a scruple not an opinion III. The next and principal thing concerning ice is the bigness of it which I find by the Relations partly of some Acquaintances of my own and partly of some Navigators into the North to be sometimes not only prodigious but now and then scarce credible And therefore as I shall mention but few instances that I have selected out of the best Journals and other writings I have met with so I shall add a few more Testimonies to keep them by their mutual support from being entertain'd with a Disbelief which their strangeness would else tempt men to Of the vastness of single mountains of ice the most stupendious Example that for ought I know is to be met with in any language but ours is that which I formerly took notice of out of the Dutch Voyage to Nova Zembla which was ninty six foot high that is above twenty foot higher than on a certain occasion I found the Leads of Westminster Abbey to be But 't is probable that our Captain James met with as great if not greater For though in some places he mentions divers hills of Ice that were aground in 40. fathom water and consequently were as deep under water as that newly taken notice of out of the Hollanders And though he elsewhere mentions other pieces of no less depth and twice as high as his top-Mast head and this in June yet elsewhere and long after relating his return home he has this passage We have sail'd through much mountainous Ice far higher then our Top-Mast head But this day we sail'd by the highest that I ever yet saw which was incredible indeed to be related But the stupendiousest piece for heighth and depth of single Ice that perhaps has been ever observ'd and measur'd by men is that which our Famous English Seaman Mr. W. Baffin whose name is to be met with in many modern Maps and Globes mentions himself to have met with upon the coast of Greenland whose whole Relation I shall therefore subjoyn not only because of the stupendiousness of this piece of ice but because he takes notice of an observation which I knew not to have been made by any and comes somewhat near the estimate we formerly made of the proportion betwixt the extant and immers'd parts of floating ice only the following Estimate makes the extant part somewhat greater then we did which may easily proceed from other mens having as Mr. Baffin here does grounded their computation upon what occurr'd to them at Sea or in salt water where the ice must sink less then in fresh water such as my Estimate suppos'd Our Navigators words then are these The 17. of May we sail'd by many great Islands of Ice some of which were above 200. foot high above water as I prov'd by one shortly after which I fonnd to be 240. foot high and if the report of some men be true which affirms that there is but one seventh part of Ice above water then the height of that piece of Ice which I observed was one hundred and forty fathoms or one thousand six hundred and eighty foot from the top to the bottom This proportion I know doth hold in much Ice but whether it do so in all I know not Thus far of the height and depth of single pieces of ice as for the other Dimensions the length and breadth I remember not that I have read of any that had the Curiosity to measure the extent of any of them excepting Captain James whose Ship being once arrested between some flat and extraordinary large pieces of ice he and his men went out to walk upon them and he took the pains to measure some of the pieces which he says he found to be a 1000. of his paces long And probably among so many mountains and Islands of ice there would have been found some intire pieces of a greater extent then even these if men had had the curiosity to measure them Hitherto we have treated of the bigness of single pieces of ice we will now proceed to say something of the dimensions of the aggregates of many of them among which having selected four or five as the principal I remember my self to have yet met with I presume it will be sufficient to subjoyn them only About ten of the clock we met with a mighty bank of ice being by supposition seven or eight leagues or twenty four miles long says that experienced English Pilot James Hall in his Voyage of Denmark for the discovery of Greenland Another of our English Navigators mentions that even in June all the Sea wherein he was indeavouring to sail as far as he could see from the top of a high hill was covered with ice saving that within a quarter of a mile of the shore it was clear round about once in a Tide By which last clause it seems that this vast extent of ice was either one intire floating Island or at least a vast bank or rand as some Seamen term it of ice But the strangest account of banks of ice that
of five Canons But the next passage is more directly pertinent to our present subject and is couch'd in these words About twelve of the clock this night it being still calm we found our selves suddenly compassed round about with great Islands of ice which made such a hideous noise as was most wonderful so that by no means we could double the same to the westward wherefore c. Of these kind of icy thunders as some travellers call them there are divers instances to be met with mention'd in the several Voyages of the Hollanders particularly in those to Nova Zembla But many of those noises seem to be made by the dashing of the great pieces of ice against one another But if it happen when the ice as sometimes it is said to do seems to cleave as it were of its own accord to us that live in a temperate Climate it may be a matter of some dispute whence these loud ruptures of ice may proceed For Olaus Magnus in the Chapter above cited does not improbably ascribe them to the warm exhalations that in some places ascend out of the ground And I remember in favour of this opinion that I once caused divers pieces of thick ice to be brought out of a cool place into a somewhat warm room and listening observ'd a noise to come from them as if it had been produced by store of little cracks made in them but somewhat or other prevented me from repeating the Experiment and satisfying my self about the Conjecture But having lately inquired of an intelligent Polander that has travelled much upon these icy plains he agreed with our Author and others as to the frightful noise that are produc'd by these cracks of ice but affirm'd upon his own observation for that I particularly inquired after that these great clefts were often made not by thawing heat but by excessive cold and that he had taken notice of them in extremely sharp weather Indeed we sometimes observe that in very bitter frosts the frozen ground will cleave as we elsewhere have occasion to take notice But whether that be not a different case from this or whether the Polonian Gentleman were not mistaken or whether both these mention'd accounts of the cleaving of ice may on different conjunctures of circumstances take place we leave to farther inquiry There is a tradition concerning ice about the famous Volcan-Hecla in Island which though verily believ'd among the superstitious vulgar of those parts is spoken of so slightly by Blefkenius who being upon that coast had the curiosity to sail purposely thither that I think it not worth while to take any farther notice of it But 't were too tedious to set down in this Section which the strangeness and variety of the Theme has made so prolix already the other things that may be mentioned without impertinency concerning ice and therefore we shall here desist from so laborious a task as also omit the handling of snow and hail For though they are reducible to ice yet I shall at least suspend the treating of them partly because Bartholinus and Meteorologists have sav'd much of my labour and partly for the reason newly intimated so that we shall conclude this Section as soon as we have taken notice that there is yet somewhat relating to ice which being in itself considerable and whereof hitherto no experimental account appears to have been given what we our selves have tried about it may challenge to be treated of apart Title XVI Experiments and Observations touching the duration of Ice and Snow and the destroying of them by the Air and several Liquors 1. IT may be an Experiment as well instructive as new to determine what liquor dissolves ice sooner then others and in what proportion of quickness the solutions in the several liquors are made For Men have hitherto contented themselves to suspect in general that there are other liquors potentially hot wherein ice will sooner dissolve then it will in water But this opinion either being grounded upon no Experience at all or taken up upon the sight of what happens to pieces of ice which no care was taken 〈◊〉 reduce to the same bulk and figure no more then to measure attentively how long one outlasted the other we thought fit to try if we could not bring this matter to Experiment and make a determination in it though not exactly true yet less remote from exactness then had been yet for ought I know so much as attempted 2. In order to this we procured some bullet moulds and having first carefully stopped the little Crevice that is wont to remain betwixt the two halfs of the mould with a good close Cement we afterwards filled them with water and carefully closed up the orifice of the hole at which the water was poured in and then setting the mould to freez in ice and salt we found it difficult enough to keep the water more or less of it from running away through some unperceiv'd passage before the cold could have time by congealing it to arrest it But after a while when we had thus made a bullet of ice we found it a new and greater difficulty to get it whole out of the moulds without warming them for by that way we could indeed loosen the ice but then we could not avoid thawing it too and that most times not uniformly wherefore we tried by greasing the inside of the moulds to keep the ice from sticking so close to them notwithstanding the distention the water suffered by its being frozen but that we might pick out the bullet entire and this succeeding well enough we hoped by this way to obtain our end which was to have a competent number of pieces of ice of equal bulk and of the same figure to be put at once to thaw in several liquors but we could by no means procure moulds which had any number of distinct cells of the same bigness those long pairs of moulds that were to be met with in shops having their distinct cells generally made on purpose of very different bignesses which rendred them altogether useless for our design Wherefore we were fain for want of an exacter way to take a glass pipe of the most even and Cylindrical that we had and of a bore capable to admit a big mans little finger this glass being stopt at one end and kept open at the other was filled to the height of about half a foot or more of fair water and ice and salt being heaped up about it that the cold might reach as far as the 〈◊〉 did it was quickly frozen In the mean while I had caused several wide mouth'd glasses to be brought into my Chamber wherein by reason of some indisposition that hindred me from going abroad I kept some fire and having poured several liquors into these glasses which had been placed all on a row we suffered them to rest there a while that the ambient Air might have time to reduce them as far
hath taught me preserve ice and snow for a very long time Appendix to the XVI Title AN eminent instance to confirm what is delivered at the close of the foregoing Section is afforded us by the conservatories wherein snow and ice are kept all the Summer long Of these I have seen in Italy and elsewhere but supposing I had the command of some Italian and other books wherein I should meet with the dimensions and other circumstances that belong to them my finding my expectation disappointed by those books makes me think it very well worth while to subjoyn somewhat about things that may give us opportunity of making a multitude of Experiments about Cold. And therefore meeting the other day by good chance with my ingenious friend Mr. J. Evelyn his inquisitive travels and his insight into the more polite kinds of knowledge and particularly Architecture made me desire and expect of him that account of the Italian way of making conservatories of snow that I had miss'd of in several Authors and having readily obtain'd my desire of him I shall not injure so justly esteem'd a style as his to deliver his description in any other words then those ensuing ones wherein I received it from him The snow Pits in Italy c. are sunk in the most solitary and cool'd places commonly at the foot of some mountain or elevated ground which may best protect them from the Meridional and Occidental Sun 25. foot wide at the orifice and about 50. in depth is esteem'd a competent Proportion And though this be excavated in a Conical form yet it is made flat at the bottom or point The sides of the Pit are so joyc'd that boards may be nail'd upon them very closely joynted His Majesties at Greenwich newly made on the side of the Castle-hill is as I remember steen'd with Brick and hardly so wide at the mouth About a yard from the bottom is fix'd a strong Frame or Tressle upon which lies a kind of woodden grate the top or cover is double thatch'd with Reed or Straw upon a copped frame or roof in one of the sides whereof is a narrow door-case hipped on like the top of a Dormer and thatch'd and so it is complete To conserve Snow They lay clean Straw upon the grate or wattle so as to keep the Snow from running through whilest they beat it to a hard cake of an icy consistence which is near one foot thick upon this they make a layer of straw and on that snow beaten as before and so continue a bed of straw and a bed of snow S. S. S. till the pit be full to the brim Finally they lay Straw or Reed for I remember to have seen both a competent thickness over all and keep the door lock'd This grate is contriv'd that the snow melting by any accident in laying or extraordinary season of weather may drain away from the mass and sink without stagnating upon it which would accelerate the Dissolution and therefore the very bottom is but slightly steen'd Those who are most circumspect and curious preserve a tall Circle of shady trees about the pit which may rather shade then drip upon it Thus far this learned Gentlemans account of Conservatories of Snow And on this occasion I might add what the Dutch in their Nova Zembla Voyage relate namely that the three and twentieth of June though it were fair Sunshiny weather yet the heat was not so strong as to melt the Snow to afford them water to drink and that in spight of their being reduc'd to put Snow into their mouths to melt it down into their throats they were compelled to indure great thirst But because it was in so cold a Climate that this duration of the Snow was observ'd I shall rather take notice that in the Alps and other high mountains even of warmer Climates though the snow doth partly melt towards the end of Summer yet in some places where the reflection of the Sun beams is less considerable the tops will even then remain covered with snow as we among many others have in those Countries observed And for further confirmation of the Doctrine deliver'd at the end of this 16. Title I shall subjoyn a Passage which having unexspectedly met with in an unlikely place of Captain James's Voyage I think not fit to leave unmention'd here not only because 't is the sole artificial observation that I yet met with concerning the lasting of ice and so may recommend to us the Ingenuity of an Author whose Testimony we somewhat frequently make use of but because the observation is in it self remarkable and notwithstanding the difference of places may serve for the purpose we alledge it Our Navigators words are these I have in July and in the beginning of August taken some of the Ice into the ship and cut it square two foot and put it into the Boat where the Sun did shine on it with a very strong reflex about it And notwithstanding the warmth of the Ship for we kept a good fire and our breathings and motions it would not melt in eight or ten days And it is also considerable to our present purpose what the same Author elsewhere has about the durableness of the Congelation of the ground not yet thaw'd at the beginning of June For the ground says he was yet frozen and thus much we found by experience in the burying of our men in setting up the Kings Standard towards the latter end of June and by our Well at our coming away in the beginning of July at which time upon the land for some other reasons it was very hot weather Title XVII Considerations and Experiments touching the Primum Frigidum 1. THe dispute which is the Primum Frigidum is very well known among Naturalists some contending for the Earth others for the Water others for the Air and some of the Moderns for Nitre But all seeming to agree that there is some Body or other that is of its own nature supremely Cold and by participation of which all other cold Bodies obtain that quality 2. But for my part I think that before men had so hotly disputed which is the Primum Frigidum they would have done well to enquire whether there be any such thing or no in the sense newly express'd For though I make some scruple resolutely to contradict such several Sects of Philosophers as agree in taking It for granted yet I think it may be not irrationally Question'd and that upon two or three accounts 3. For first it is disputable enough as we shall hereafter see whether cold be as they speak a positive quality or a bare privation of heat and till this question be determined it will be somewhat improper to wrangle sollicitously which may be the Primum Frigidum For if a Bodies being cold signifie no more then it s not having its insensible parts so much agitated as those of our Sensories by which we are wont to judge of tactile
qualities there will be no cause to bring in a Primum Frigidum upon whose account particular Bodies must be cold since to make this or that Body so it suffices that the Sun or the Fire or some other agent whatever it were that agitated more vehemently its parts before does now either cease to agitate them or agitate them but very remisly So that till it be determin'd whether cold be a positive quality or but a privative it will be needless to contend what particular Body ought to be esteem'd the primum frigidum in the sense above specifi'd 4. Secondly Though it be taken for granted not only by the Schools but by their Adversaries the Chymists that heat and moisture driness and gravity and I know not how many other qualities must have each of them a 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 or a principal subject to reside in upon whose account and by participation of which that Quality belongs to the other Bodies wherein it is to be met with though this be so I say yet we have elsewhere fully enough manifested that this fundamental Notion upon which much of the Doctrine of Qualities is both by Aristotelians and vulgar Chymists superstructed is but an unwarrantable conceit and therefore not sufficient for a wary Naturalist to build the Notion of a primum frigidum upon there being indeed many qualities as gravity and figure and motion and colour and sound c. of which no true and genuine 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 can for ought I could ever yet discover be assigned and because heat and cold are look'd upon as Diametrically opposite Qualities we may consider that it will be very hard to show that there is a 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 of heat since stones and mettals and plants and animals and very few excepted all consistent Bodies we are conversant with may by motion be brought to heat which to attribute to the participation of some portion or other of the imaginary Element of fire is not only precarious being affirm'd by many and prov'd by none but erroneous or at least needless as we have more at large declar'd in other papers 5. A third thing that induces me to question whether there be a primum frigidum is that among those Bodies that the chiefest Sects of Philosophers whether Ancient or Modern have pitch'd upon there is not any that seems clearly to deserve the title of the primum frigidum But to make this appear we must distinctly though as briefly as our design will permit consider those four several Bodies which we have at the Beginning of this Section taken notice of to stand in competition in the Opinions of Philosophers for the title of primum frigidum 6. First then Plutarch and others contend that it is the Earth but to omit other Arguments we see that the Earth is frozen not by its own cold but by its vicinity to the Air as may be argued by this viz. that the congealing cold even in the midst of Winter affects but the surface of the Earth where it borders on the Air and seldom pierces above a few feet or at most yards beneath that part wherein the Earth is exposed and immediately contiguous to the Air as may appear by what we have formerly deliver'd concerning the small depth to which frosts reach in the ground And therefore if the Earth be protected from the Air though by so cold a Body as water it may be kept unfrozen all the Winter long as may be gathered from that remarkable practise in the great Salt-marshes of the French Islands of Xaintonge where as a diligent Writer of that Countrey very well vers'd in the making of the French Salt informs us when once the season of Coagulating Salt by the heat of the Sun is quite past the Owners are careful by opening certain Sluces to overflow all the Banks and Dams that make and divide the Salt-ponds and serve for the Workmen to pass to and fro for says my Author in his own language if they left those Marshes or Salt-works uncovered the frost would make such havock amongst them that it would be necessary to make them up again every year but by means of the water they are preserv'd or kept in repair from year to year which practise I the rather mention because the hint it affords as it is considerable to our present purpose so it may on some occasions be applicable to practises useful to humane society 7. Besides the Earth being according to those we reason with the coldest heaviest and solidest of Elements it is not so probable as to excuse them from the need of proving it that those excessively cold Agents that freez the Clouds into Snow and Hail should be 〈◊〉 Exhalations carried up to the middle Region of the Air especially since it must be done by Agents either hard to be guess'd at or considerably hot And 't is not easie to give a reason why if Elementary Corpuscles steaming from the Earth have such a congealing cold where they are disunited and but interspers'd among the particles of Air the Mass of the Earth it self whence those exhalations are suppos'd to proceed should not be able also to congeal water since the Terrestrial Corpuscles being more thick set and united in a Clod of Earth then in an equal portion of the Atmosphere it seems that where the frigorifick matter is more dense the cold should be more vehement as Philosophers observe that heat is more intense in a glowing bar of Iron then an equal portion of the flame of kindled Straw 8. But not to repeat what we formerly mention'd about Colds being a Privation there is another Argument against the Earths being the primum frigidum and that is taken from the Subterraneal fires which breaking forth in many places of the Earth as in Aetna Vesuvius Hecla the Pico of Tenariffe c. seem to argue a Subterraneal fire upon whose existence not only many Chymists build great matters but even divers Philosophers have adopted it and the learned Gassendus himself seems so far to countenance it as to imploy it as one Argument of the Earths being naturally neither hot nor cold The mention of this Subterraneal fire brings into my mind some things that I have met with amongst good though not Classick Authors and amongst men that have been either diggers of or conversant in Mines not improper to be here taken notice of For though I do not now intend to declare my opinion about the Central fire either of the Chymists or Cartesians and though the Examples newly mention'd and such other seem to me but very inconsiderable in reference to the whole Earth yet 't is observable to our present purpose that there should be so much Subterraneal heat or warmth at least generally to be met with For even where there appear no manifest signs of Subterraneal fires I have known those that were wont to go to the Bottom of deep Mines complain that a very
cold or upon whose Account the Air produces them And if these be duly applied water will be congealed whether Air comes to touch the surface of it or no nay though Bodies which the Air can never penetrte nor congeal any of their parts be interpos'd as may appear by the Experiments formerly mention'd of freezing water included in glass bubbles and suspended in oyl of Turpentine and other uncongealed Liquors and it is worth taking notice of by them that conclude the Airs being the primum frigidum from the waters beginning to freez at the Top where 't is contiguous to the Air that it is there also where the Ice begins to thaw 21. Besides the three Opinions we have hitherto examin'd there is a fourth that justly deserves to be seriously consider'd for the learned and ingenious Gassendus is suppos'd though I doubt how truly to be the Author of it and though according to his custom he speaks warily and not so confidently of it yet in his last writings he much countenances it yet some eminently learned men as well of our own as of other Nations have resolutely enough embraced it According then to these the congelation of Liquors and the cold we meet with in the Air Water and other Bodies proceeds from the admixture of Nitrous exhalations or Corpuscles introduc'd into them And as I have a great respect for divers of these mens persons so I like very well in their opinion that they do not ascribe the supreme degree of frigefactive Virtue to the Air it self but to some adventitious thing that is mingled with it but whereas they pitch upon Nitre as the grand Universal efficient of cold I confess I cannot yet fully acquiesce in that Tenent For though I am not averse from allowing Salt-Petre to be one of those Bodies that are endued with a refrigerating power and to be copiously enough dispers'd through several portions of the Earth yet for ought I know there may be not only divers other causes of cold but divers other Bodies qualified to be Efficients of cold as well as Salt-Petre 22. And first if cold be not a positive quality but the absence of heat the removing of calorifick Agents will in many cases suffice to produce cold without the introduction of any Nitrous particles into the Body to be refrigerated But because 't is disputable whether cold be a positive quality or no we will urge this Argument no further till the Controversie be decided and till then as it will remain not improbable we propose it as no other but proceed to the next 23. In the second place I see not as yet any proof that the great cold we have formerly mention'd to be met with in the depths of that vast Body the Sea especially when it is greater elsewhere then nearer the Top where the Air may better communicate its coldness to it must be the effect of Nitrous Atoms which must certainly swarm in prodigious multitudes to be able to refrigerate every drop and sensible particle of so stupendiously vast a Body as the Ocean Besides that I remember not to have found or known it observ'd that Nitre especially in vast quantities reaches near so deep in the Earth as those parts of the Sea that are found exceeding cold And as the halituous part of Nitre is more dispos'd to fly up into the Air then dive down into the Sea so we find no great documents of its having its grosser and sensible parts abounding in the Sea-water since the evaporations of that leaves not behind it Salt-petre but common Salt But these though no light considerations are not those that most weigh with me 24. For in the next place I am not satisfied with the Experiences I find alledged to prove that 't is by Nitre that the Air and the neighboring parts of the Earth and Water not to repeat the objections I lately borrowed from the Sea receive their highest degrees of Cold. For when Gassendus and others tell us that 't is Nitre resolv'd into exhalations that make the gelid Wind which refrigerates all things it touches and penetrating into the water congeals it this I say to me will seem precarious untill Gassendus or some other for him tell us what Experiments they are which he seems in one place to intimate that this new Doctrine depends on for I confess that for my part I who have perhaps had more opportunity to resolve Nitre have seen no great feats that the steams of it have done more then those of other saline Bodies in the production of cold and the spirit of Nitre which is a liquor consisting of the volatile parts of that resolved salt not only does not that I have observed appear to the touch to have considerably if at all a greater actual cold then that of divers other Liquors but seems to have a potential heat For whether or no the Exhalations of Nitre be able to congeal water into Ice I have formerly observ'd serv'd that the spirit of Nitre or Aqua fortis will dissolve Ice into water very near if not altogether as soon as the spirit of 〈◊〉 it self which inflamable Liquor is generally acknowledg'd to be in a high degree potentially hot If Gassenaus did not mean such steams of 〈◊〉 as these which I have been 〈◊〉 of it had not been amiss to have signified what other kind of Corpuscles of resolved Nitre he meant without leaving his Reader to divine it and if we may judge of other Experiments which we lately took notice that Gassendus seems to intimate by that which he sets down a little after compar'd with that he had mention'd a little before I am not likely much to be convinc'd by them but shall rather be tempted to suspect that learned man might be impos'd upon by others to write that as matter of fact which he never had tried and yet own not the having it only by report For whereas he seems to 〈◊〉 that dissolved Nitre mingling it self with water freezes it and that in Summer yet I must freely 〈◊〉 that although 〈◊〉 other Learned Moderns teach the same thing but without any mans avouching it that I know upon his own experience I who am no 〈◊〉 to Nitrous Experiments have never been able to produce or so fortunate as to see any such effect and 〈◊〉 somewhat strange to me that Chymists who make such frequent solutions of Nitre and ofrentimes with less water then is sufficient to dissolve it all so that by consequence the proportion of the Nitre to the Water must have run through almost all the possible measures of proportion should never so much as by chance as I can hear have observ'd any such matter and that which makes me thus interpret Gassendus his meaning though in one of the two passages wherein he sets down this Experiment he mentions also snow or ice to be added to the Nitre is that in the first of those two passages he ascribes the congelation to
I now consider not the causes of the Intenser Coldness in the Air without taking them in And the opinion I incline to has at least this advantage that the Air seems to be as rightfully term'd cold as Iron Marble Mercury Crystal Salt-petre and such other Bodies which men unanimously look upon as such there being none of these to which the Argument imploy'd against the coldness of the Air is not applicable save that the Air being a fluid of a looser and finer Texture does sooner receive and lose the impressions of heat and cold And yet if a Block of Marble for instance or an Iron Bullet were remov'd into one of those empty spaces that Gassendus and some others suppos'd to be beyond the bounds of this world I see not why it should not be rather cold then either warm or in a state of perfect Neutrality Since when the Corpuscles of Heat and those of Cold had extricated themselves and were flown away into the neighbouring Vacuum the component Particles of the stone or metal whose implicated Texture would hinder their Dissilition remaining much less agitated then our Organs of feeling are by the warm blood and spirits that vivifie them must if applied to those sensories appear Cold. 2. But I shall not upon this subject spend any farther discourse since perhaps the dispute either may be or at least may easily be made Verbal For in case those I argue with should so explain their opinion as not to deny that in its own nature the Air left to its self may be reputed Cold in reference to the sensories of men who are warm animals But say that nevertheless comparing it indefinitely to other then humane bodies here below it is so easily susceptable of both the contrary qualities that neither of them seems predominant in it and that when it is considerably either cold or hot it is made so by adventitious agents I shall not much contend with them especially if it can clearly be made our that there are great quantities of such cold spirits as Cabaeus and Gassendus suppos'd to be universally productive of cold more or less in all bodies where they get admission but of these cold spirits more perhaps elsewhere Our principal business in this Section being to deliver Experiments and Observations and because we shall mention but few of the former sort we will dispatch them first 3. November the 20. 1662. we took a Weather-glass fill'd to a convenient height with well rectifi'd spirit of Wine and Hermetically seal'd this we inclos'd in a glass Receiver of a Cylindrical form of about two inches Diameter and about a foot and a half high and having cemented on the Receiver we let it alone for some hours that it might perfectly cool Then drawing out the Air and watching it narrowly we observ'd that the liquor in the Weather-glass descended a little though but a very little upon the first Exuction of the Air and a little though it seem'd somewhat less upon the second but afterwards we did not find it sensibly to descend This subsidence of the liquor in all amounting to about the length of a Barley corn we attributed to the stretching of the glass by the spring of the included Air when the ambient was withdrawn and accordingly upon our allowing a Regress to the excluded Air we saw the spirit in the Thermometer rise about half a Barley-corns length to the place whence it began to subside Afterwards we suck'd out and let in the Air of the Receiver as before with like success as to the descent and remounting of the liquor 4. N. B. We tri'd with a very hot Handkerchief appli'd in a convenient place to the outside of the Receiver whether the included Weather-glass would receive impressions from it the Air that was wont to be intermediate being remov'd but we did not find the liquor in the Weather-glass sensibly to swell either by this way or by casting upon it the concentrated beams of a candle trajected through a double convex glass But when the Air was readmitted into the Cavity of the Receiver then the same Handkerchief heated a fresh and applied made the spirit of Wine sensibly though but little more to ascend Of which yet it seem'd something difficult by reason of the Nicety of the Experiment to estimate with any thing of certainty the Cause So that upon the whole matter till the Experiment be repeated in Airs of differing tempers to verifie whether 't was the withdrawing of the wonted pressure or the recess of the substance of the Air that made the liquor included in the Thermoscope subside and till the Experiment be repeated with the further observation of other circumstances which reiteration of the Trial we intended but were by intervening accidents hindred the recited Experiment will not afford much more then good hints towards the Discovery of the Temperature of the Air. 5. I have elsewhere taken notice that air included in Vessels sufficiently strong and well clos'd was not sensibly or at least not considerably condens'd by Cold but when the Air was not so included as not to be in some part or other expos'd to the pressure of the outward Air or Atmosphere it would then by a degree of Cold capable to freez water be manifestly reduc'd into a less room But how much this Contraction or Condensation of the air may amount to I did not there subjoyn nor has the measuring of it been that I know of attempted by any man Wherefore we thought fit to indeavour something in this kind of which we shall annex a brief account whereby it will appear upon the whole matter that in the Climate we live in the Cold does not so considerably condense the Air as most men seem to have hitherto imagin'd 6. And first it will not be amiss to intimate that among other ways we tried to measure the shrinking of the Air by sealing it up in glasses furnish'd with long and very slender stems that by breaking off the tips of those glasses immers'd under water when by the Cold Air of a frosty night or the Circumposition of snow and salt the included air was highly refrigerated the water might by the pressure of the Atmosphere upon it be impell'd into the Cylindrical cavity of the broken glass and by its greater or lesser Ascent therein shew how much the internal Air had been made to shrink upon the account of the Cold. But this way for reasons too long to be here deduc'd we found it troublesome and difficult to practise with any thing of certainty Nor did we ever that I remember by this way bring the refrigerated air to lose above a 30. part of its former dimensions 7. We would have tried also to measure the Condensation of the air by the ascent of water into the stem of a Bolthead so inverted that the orifice of the stem might be under the surface of the water and the Bolt-head kept erected But this way we
we must not here treat indefinitely the strange effects of cold upon other bodies being most of them produc'd by the intervention of the cold first diffus'd in the Air and those are treated of in a distinct Section wherefore we shall now give two or three instances of the sudden operations of the Cold harbour'd in the Air. The formerly mention'd English Ambassador into Russia Dr. Fletcher gives us two instances very memorable to our present purpose When you pass says he out of a warm Room into a Cold you will sensibly feel your breath to wax stark and even stifling with the cold as you draw it in and out So powerfully and nimbly does the intensely refrigerated Air work upon the Organs of respiration And whereas a very credible person now chief Physician to the Russian Emperor being ask'd by me concerning the truth of what is reported sometimes to happen at Musco and is reputed the eminentest proof that is readily observable of the extreme coldness of the air assur'd me that he himself saw the water thrown up into the air fall down actually congeal'd into ice Dr. Fletcher confirms this Report For our Ambassador also says That the sharpness of the Air you may judge of by this for that water dropped down or cast up into the Air congeal'd into Ice before it come to ground And I remember that inquiring about the probability of such Relations he answered me That being at the famous Seige of Smolensko in Russia he observ'd it to be so extremely cold in the fields that his Spittle would freez in falling betwixt his mouth and the ground and that if he spit against a Tree or a piece of wood it would not stick but fall to the foot of it 17. Among the Phaenomena of Cold relating to the air I endeavour'd to observe whether upon the change of the Weather from warm or mild to cold and frosty there would appear any difference of the weight of the Atmosphere by its being plentifully furnish'd with a new stock of such frigorifick Corpuscles as several of the modern Philosophers ascribe its coldness to but though I several times observ'd by comparing a good Barometer and sometimes also unseal'd Weather-glasses furnish'd one with a tincted Liquor and the other with Quicksilver with a good seal'd Weather-glass furnished with pure spirit of Wine that upon the coming in of clear and frosty weather the Atmosphere would very early appear sensibly heavier then before and continue so as long as the cold and clear weather lasted yet by reason of some considerations and Trials that breed some scruple in me I refer the matter to more frequent and lasting observations then I yet have been able to make in which it will concern those that have a mind to prosecute such Trials not only to consider whether or no the increased gravity of the Atmosphere may not proceed from some other Cause then the coming of frigorifick Atoms into the Air but to have a special care that their Barascopes be more carefully freed from the Air that is wont to lurk in Quick silver it self as well as other Liquors then those in the making of the Torricellian Experiment Tubes usually are least that Air getting up into the deserted part of the Tube do by its expansion and contraction obtain an unsuspected interest in the rising and falling of the subjacent Mercurial Cylinder and so impose upon them 18. Another Effect that the Cold especially in Northern Countries has oftentimes upon the Atmosphere is the making the Air more or less clear then usually it is For in the Northern Voyages the Seamen frequently complain of thick and lasting Fogs whose causes I shall not now consider but some help to guess at them may be given by what we are about to add namely that it very frequently happens on the contrary That when the cold is very intense the air grows much clearer then at other times probably because the Cold by condensing precipitates the vapours that thicken the air and by freezing the surface of the earth keeps in the steams that would else arise to thicken the air Not to dispute 〈◊〉 it may not also somewhat repress the vapours that would be afforded by the water it self since some of our Navigators observe that even when it was not cold enough to freez the surface of the Sea it would so far chill and infrigidate it that the snow would lye on it without melting 19. I remember a Swedish extraordinary Ambassador and a very knowing person whom I had the honour to be particularly acquainted with would say when he saw a frosty day accompanied with great clearness that it then look'd like a Swedish winter where when once the frosty weather is setled the sky is wont for a very long time to be very serene and 〈◊〉 and here in England we usually observe the sharpest frosty nights to be the clearest But to confirm our Observation by a very remarkable instance I shall borrow it 〈◊〉 a Navigator very curious of Celestial Observations which circumstance I mention to bring the greater credit to the following observation of Captain James which in his Journal is thus delivered The thirtieth and one and thirtieth of January there appeared in the beginning of the night more Stars in the Firmanent then ever I had before seen by two thirds I could see the Cloud in Cancer full of small Stars 20. To determine what effect the coldness of the air may have upon the Refractions of the Luminaries and other Stars I look upon as a work of no small difficulty and that would require much consideration as well as time wherefore I shall only add two or three narratives supplied me by Navigators without adding at present any thing to the matters of fact 21. The first is that famous Observation of the Dutch in Nova Zembla who take great pains to evince by several circumstances some of them highly probable that they were not mistaken in their account of time according to which they concluded that they saw the Sun whom they had lost sight of eleven weeks before about fourteen days sooner then he ought to have appear'd to them which difference has been for ought I know to the contrary by all that have taken notice of it ascrib'd to the strangely great Refraction in that Gelid and Northern air 22. And as for that other extremely cold Country where Captain James wintered it appears by his Journal that he there made divers Celestial and other observations which gave him opportunity to take notice of the Refraction and he seems to complain that he found it very great though among the particulars he takes notice of there are some that seem not very strange nor are there any that are near so wonderful as that newly mention'd of the Hollanders in Nova Zembla however in regard of the extreme coldness of the Winter air in Charleton Island it may be worth while to take notice of the following passages
but such as eat flesh as Bears and Foxes c. although Nova Zembla lyeth 4 5 and 6. degrees more Southerly from the Pole then the other land aforesaid And to this purpose I remember what is related by the learned Josephus Acosta concerning the Heats and Colds in the Torrid Zone and elsewhere When I pass'd says he to the Indies I will tell what chanc'd unto me having read what Poets and Philosophers write of the burning Zone I perswaded myself that coming to the Aequinoctial I should not indure the violent heat but it fell out otherwise for when I pass'd which was when the 〈◊〉 was there for Zenith being entered into Aries in the moneth of March I felt so great a cold as I was forc'd to go into the Sun to warm me what could I else do then but laugh at Aristotles Meteors and his Philosophy seeing that in that place and at that season when as all should be scorch'd with heat according to his rules 〈◊〉 and all my companions were a cold in truth there is no Region in the world more pleasant and temperate then under the Equinoctial although it be not in all parts of an equal temperature but have great diversities The burning Zone in some parts is very temperate as in Quitto and on the plains of Peru in some parts very cold as at Potosi and in some veryhot as in Ethiopia Brasile and the Molucques And within two Chapters after he discourses more largely of some of these Particulars And again Chapter the 12. You may continually says he see upon the tops of these mountains snow hail and frozen waters and the cold so bitter as the grass is all wither'd so as the men and beasts which pass that way are benumm'd with cold This as I have said is in the burning Zone and it happens most commonly when they have the Sun for Zenith These Testimonies of a learned man that writes upon his own knowledge I thought it worth producing to make it probable that as in several Countries the heat does not always answer to the nearness of places to the Line so in Northern Regions the cold may not always be proportionate to their vicinity to the Pole In Mr. Hudsons second voyage written by himself he mentions that above 71. degrees though they were much pester'd with ice about the end of June that day when this hapned was calm clear and hot weather adding of the next day also that it was calm hot and fair weather And Acosta tells us that we see these differences not only on the land but also on the Sea there are some Seas where they feel great heat as the report of that of Mazambigus and Ormus in the east and of the Sea of Panama in the west There are other Seas in the same degree of height very cold as that of Peru in the which we were a cold when we first sail'd it which was in March when the Sun was directly over us In truth on this continent 〈◊〉 the Land and Sea are of one sort we cannot imagine any other cause of this so great a 〈◊〉 but the quality of the wind that 〈◊〉 refresh them But to multiply no more instances we shall conclude with this one That Charleton Island where Captain James winter'd and of which we so often have occasion to make mention in our History though it seems by the effects to be a colder Region then even the Countrey about Musco and perhaps as cold as Nova Zembla it self yet Captain James who had several times occasion to take the latitude of it and assignes it the same Elevation and consequently the same Distance from the Pole with Cambridge whose latitude he reckons to be 51. degrees besides minutes and whose air is very well known to be very temperate And it is remarkable that though this place whose latitude is short of 52. degrees was found uninhabitable by reason of the cold yet not only in Mr. Hudsons Voyage the writers admonish the Readers to take notice That although they ran along near the shore they found no great cold which made them think that if they had been on shore the place is temperate And yet in this place they reckon themselves to have reach'd the 78. degree of latitude And our recenter Navigations inform us that several parts of Greenland to which this newly mentioned coast belong'd are well enough inhabited And one of our English Navigators assures us that the true height of Pustozera in Russia is no less then 68. degrees and a half if not more and yet that is a town not only well inhabited but of great trade but in Hudsons voyage I find what is more strange That under the 81. degree of latitude beyond which they discovered land very far off but beyond which none is thought to have actually sail'd toward the Pole they found it during the whole day clear weather with little wind and reasonable warm And beyond 80. degrees they not only found a stream or two of fresh water but found it hot on the shore and drank water to cool their thirst which they also commended II. The next observable I am to propose about the coldness of the Air is this That the degrees both of Heat and Cold in the air may be much greater in the same climate and the same place at several seasons of the year or even at several times of the same day then most men would believe For the proof of this Proposition we shall subjoyn two sorts of Testimonies of Travellers and Navigators the former shewing that in Countries where it is very cold in Winter it may 〈◊〉 be hot in Summer and the latter manifesting that even on the same day as well as in the same place the heat and cold that succeed one another may be one of them sensible though the other were extreme or may perhaps be both of them considerable To make this good we shall produce the following Testimonies 1. Dr. Giles Fletcher English Ambassador to the Muscovian Emperor in his Treatise of Russia and the adjoyning Regions has this memorable passage to our present purpose The whole Countrey says he differeth very much from it self by reason of the year so that a man would 〈◊〉 to see the great alteration and difference betwixt the Winters and Summers in Russia The whole Countrey in the Winter lyeth under snow which falleth continually and is sometime of a yard or two thick but greater towards the North the Rivers and other waters are all frozen up a yard or more thick how swift or broad soever they be and this continueth commonly for five moneths to wit from the beginning of November till towards the end of March what time the snow beginneth to melt so that it would breed a frost in a man to look abroad at that time and see the Winters face of that Countrey And a little after he adds And yet in the Summer time
but scarce credible that though the Cold has such strange and Tragical effects at Musco and elsewhere in Cold Countries as we have formerly mention'd especially a little after the beginning of this 18. and somewhere in the 19. Section yet this happens to the Russians and Livonians themselves who not only by living in such a Countrey must be accustomed to bitter Colds but who to harden themselves to the Cold have us'd themselves and thereby brought themselves to be able to pass to a great degree of Cold from no less a degree of heat without any visible prejudice to their healths For I remember that having inquired of a Virtuoso of unquestionable credit whether the report of our Merchants concerning this strange custom of the Muscovites and Livonians were certainly true he assur'd me that it was so at least as to the Livonians among whom being in their Countrey he had known it practis'd And the same was affirmed to me by an ingenious person a Doctor of Divinity that had occasion some years since to make a journey to Musco And the Tradition is abundantly confirm'd by Olearius whose Testimony we shall subjoyn because this seems one of the eminentest and least credible instances that we have yet met with of the strange power that custom may have even upon the Bodies of men ' T is a wonderful thing says he to see how far those Bodies speaking of the Russians that are accustomed and hardned to the Cold can endure heat and how when it makes them ready to faint they go out of their Stoves stark naked both men and women and cast themselves into cold water or cause it to be pour'd upon their Bodies and even in Winter wallow in the Snow To which passage our Author adds from his own observation particular Examples of the Truth of what he delivers 6. I had several years since the curiosity to try whether there were any truth in that tradition which is confidently affirm'd and experience by some is pretended for it that the Beams of the Moon are cold but though I were not able to find any such matter either by the ununited beams of the Moon or by the same beams concentred by such Burning-glasses as I then had yet having some years after furnish'd my self with 〈◊〉 large and extraordinary good mettalline Concave I resolv'd to try whether those beams were not only devoid of cold but also somewhat warmish since they are the Sun-beams though reflected from the Moon And we see that his beams though reflected from glasses not shap'd for Burning may yet produce some not insensible degree of warmth But notwithstanding my care to make my Trials in clear weather when the Moon was about the full and if I misremember not with a Weà ther-glass I could not perceive by any concentration of the Lunar beams no not upon a black object that her light did produce any sensible degree either of cold or heat but perhaps others with very large glasses may be more succesful in their Trials 7. On this occasion I shall add that meeting the other day in a Booksellers shop with the works of the Learned Physician Sanctorius whom I look upon as an inquisitive man considering when and where he liv'd a Picture drew my eyes to take off an Experiment whereby he thinks to evince the light of the Moon to be considerably hot which he says he tri'd by a Burning-glass through which the Moons light being cast upon the Ball of a common Weather-glass the water was thereby depressed a good way as appear'd to many of his disciples amidst whom the observation was made But though this may invite me when opportunity shall serve to repeat my Trials yet I must till then suspend my assent to his Conclusion For my Burning-glass was much better then by the Narrative his seems to have been and my Trials were perhaps at least as carefully and impartially made as his Experiment in which this may probably have impos'd upon him That performing the Experiment a company of his Scholars whilest they stood round about his Thermoscope and stoop'd as in likelihood their curiosity made them to do to see by so dim a light the event of the Experiment the unheeded warmth of their breath and bodies might unawares to Sanctorius somewhat affect the Air included in the Weather-glass and by 〈◊〉 it cause that depression of the water which he ascrib'd to the Moon beams But because this is a conjecture I intend if God permit to repeat the Experiment when I shall have opportunity to do with a more tender Weather-glass then I had by me when I made my former Observations To the XI Title BY the unsuccesfulness of the former attempts made with an Iron instrument I was invited especially being at another place where I was unfurnish'd with such hollow Iron balls as are mention'd Num. the 10. to substitute the following Experiment I caus'd a skilful Smith to take a Pistol barrel guess'd to be of about two foot in length and of a proportionable bore and when he had by riveting in a piece of Iron exactly stopp'd the touch-hole I caus'd him to fit to the nose of the barrel a screw to go as close as well he could make it and then having fill'd it to the very top with water I caus'd the screw to be thrust in which could not be done without the Effusion of some of the water as forcibly as the Party I imploy'd was able to do it that the water dilated by Congelation might not either drive out the screw or get between it and the top of the Barrel and having then suspended this barrel in a perpendicular posture in the free Air in a very cold 〈◊〉 which then unexpectedly happen'd and gave me the 〈◊〉 of making the trial I found the next morning that the 〈◊〉 water had thrust out a great part of the screw notwithstanding that to fill up intervals I had oyl'd it before and was got out betwixt the remaining part of it and the barrel as appear'd by some ice that was got out and stuck round about the screw wherefore the bitter cold continuing one day longer I did the next night cause the intervals that might be left betwixt the male and female screws to be fill'd up with melted Bees wax which I presum'd would keep the screw from being turn'd by the water and having in other points proceeded as formerly I found the next morning that the screw held as I desir'd and the preceding night having been exceeding bitter the cold had so forcibly congeal'd and expanded the water that it burst the Iron barrel somewhat near the top and made a considerable and oblique crack in it about which a pretty quantity of ice appear'd to stick besides that there were three or four other flaws at some of which smaller quantities of water appear'd to have got out At the same time that I bespoke this Iron Barrel of the Smith I order'd him to get me a brass
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
may be very warrantably question'd For 't is evident in waters we expose to freez in large vessels that the congelations begin at the surface where the liquor is 〈◊〉 to the Air and thence as the cold continues to prevail the ice increases and thickens downwards and therefore we see that Frogs retire themselves in frosty weather to the bottom of ditches whence I have had many of them taken out very brisk and vigorous from under the thick ice that cover'd the water And I have been informed by an observing person that at least in some places 't is usual in Winter for shoals of Fishes to retire to those depths of the Sea if not of Rivers also where they are not to be found in Summer Besides if Rivers were frozen at the 〈◊〉 we must very frequently meet in the emergent pieces of ice the shapes of those irregular Cavities and Protuberances that are often to be found in the uneven soils over which Rivers take their course whereas generally those emergent pieces of ice are flat as those flakes that are generated on the surface of the water Moreover if even deep rivers freez first at the bottom why should not very many Springs and Wells 〈◊〉 first at the bottom too the contrary of which nevertheless is obvious to be observ'd In confirmation of all which we may make use of what we formerly noted in the Section of the Primum Frigidum about the 〈◊〉 of the Masters of the French Salt-works who by overflowing the Banks and Causeways all the winter keep them from being spoil'd by the srost which could not be done if the waters they stand under froze as well at the bottom as at the Top. But I find that that which deceives our Water-men is that they often observe flakes of ice to ascend from the bottom of Rivers to the Top and indeed it often happens that after the hard frost has continued a while these emergent pieces of ice do very much contribute to the freezing over of Rivers For coming in some of the narrower parts of them to be stopp'd by the superficial ice that reaches on each side of the River a good way from the Banks towards the middle those flat icy bodies are easily cemented by the violence of the cold and by the help of the contiguous water to one another and by degrees straitning and at length choaking up the passage they give a stop to the other flakes of ice that either emerging from the bottom or loosened from the banks of the River or carried down the stream towards them and these being also by the same Cold cemented to the rest the River is at length quite frozen over And the reason why so many flakes of ice come from the bottom of the River seems to be that after the water has been frozen all along near the banks either the warmth of the Sun by day or some of those many casualties that may perform such a thing does by thawing the ground or otherwise loosen many pieces of that ice together with the earth stones c. that they adher'd to from the more stable parts of the banks and these heavy bodies do by their weight carry down with them the ice they are fastned to but then the water at the bottom of the river being warm in comparison of the Air in frosty weather since that even common water is so we have manifested by experience where we show how much sooner ice will be dissolv'd in water then thaw'd in Air the dispers'd ice is by degrees so wrought upon that those parts by which it held to the stones earth or other heavy bodies being resolv'd the remaining ice being much lighter bulk for bulk then water gets loose and straightway emerges and may perhaps carry up with it divers stones and clods of earth that may yet happen to stick to it or be inclos'd in it the sight of which perswades the Water-man that the flakes of ice were generated at the bottom of the river whereas a large piece of ice may carry up and support bodies of that kind of a great 〈◊〉 in case the ice it self be proportionably great so that the Aggregate of the ice and heavy bodies 〈◊〉 not the weight of an equal bulk of water On which occasion I remember that Captain James Hall in a voyage extant in Purchas relates that upon a large piece of ice in the Sea they found a great stone which they judg'd to be three hundred pound weight But of the Tradition of the Water-men we shall say no more then that this hath been discours'd but upon no great information though the best we could procure so that for further satisfaction it were to be desir'd that either by sending down a Diver or by letting down some instrument fit to feel if I may so speak the bottom of Rivers with and to try whether ice if it met with any be loose from or uniformly coherent to the ground and also bring up parcels of whatever stuff it meets with there the matter were by Competent Experiments put out of doubt We took a seal'd Weather-glass furnish'd with spirit of Wine and though not above 10. inches long in all yet sensible enough and having caus'd a hole to be made in the Cover of a Box just wide enough for the smaller end of the Glass to be thrust in at we inverted the Thermometer so that the ball of it rested upon the cover of a Box and the pipe pointed directly downwards then we placed about the ball a little beaten ice and salt and observ'd whether according to our expectation the tincted spirit that reach'd to the middle of the pipe or thereabouts would be retracted upon the refrigeration of the liquor in the ball and accordingly the spirit did in very few minutes ascend in that short pipe above an inch higher then a mark whereby we took notice of its former station and would perhaps have ascended much more if the application of the frigorifick mixture had been continued by which and another succeeding Experiment to the same purpose it seems that the condensation of liquors by cold is not always effected by their proper gravity only which ordinarily may be sufficient to make the parts fall closer together but whether in our case the contraction be assisted by some little tenacity in the liquor or by the spring of some little aerial or other spirituous and Elastick particles from which the instrument was not perfectly freed when it was seal'd up or which happened to be generated within it afterwards will be among orher things more properly inquir'd into in another place where we may have occasion to make use of this Experiment There is a famous Tradition that in Muscovy and some other cold Countries 't is usual out of Ponds and Rivers to take up good numbers of Swallows inclos'd in pieces of ice and that the benumm'd birds upon the thawing of the ice in a warm room will come to
themselves again and fly about amazedly for a while but not long survive so great and sudden a change I have in another Treatise already said somewhat about this Tradition and therefore shall now say no more of it then these two things First that I since was assur'd by a person of honour that is very curious and was commanded by a many ways great Prince to inquire out the truth of it when he was in some of those Countries where the thing is said to be familiar enough and that the 〈◊〉 and soberest persons he could ask affirm'd the thing to be true But secondly having lately inquired about this matter of a knowing person of quality that was born and bred in Poland he answered me That in the parts where he liv'd it was a very general and unquestion'd opinion that Swallows often hid themselves all the Winter under water in Ponds and Lakes and Seggy places and that the Fishermen when having broken the ice they cast their Nets for Fish do draw them up benummed but not dead so that they quickly in Stoves recover their wings but seldom after that prolong their lives But as for their being taken up in ice he told me he had not heard of it though I see not why in case they commit themselves to shallow waters as those of Ponds and Seggy places often are a sharp lasting frost may not sometimes reach them And therefore that which left me the greatest scruple about this Tradition is That this Gentleman notwithstanding his curiosity could not affirm that ever he himself had seen any example of the thing he related But I will take this occasion to add that having a mind in frosty weather to try some Anatomical Experiments about Frogs one that I imploy'd breaking in a Ditch some ice that was very thick and of which he was to bring me a quantity found in the water that was under the ice good store of Frogs besides some Toads which I found to be very lively and divers of which I kept for certain uses a good while after To confirm and to add some Paralipomena unto what I have deliver'd in the Second and in the Twentieth Titles about the frosts getting into hard and solid bodies I shall here subjoyn some particulars there omitted which I have learned partly from Experiments and partly from persons worthy of credit whom I purposely consulted about this matter And first as to the freezing of Wood we have sometimes tri'd it by purposely exposing partly other Wood and partly branches cut off from growing Trees to an intense degree of Cold by which the wood seem'd in one night to be for some little depth manifestly enough invaded by the frost But a domestick of mine having a little while since had occasion to fell an old Apple-tree on a day that had been preceded by a fortnights bitter frost came and informed me That he found that the frost had evidently pierc'd into the very middle of it though it were about a foot in Diameter And an Experienc'd Artificer whose head and hand were much imploy'd about the building of great mens houses told me that he had often seen here in England pieces of Timber it self manifestly frozen and rendred exceeding difficult to be saw'd the frost also appearing by evident signs to continue in the saw-dust And therefore it will be the less strange if in Poland the effects of Cold upon wood be more conspicuous For a learned native assur'd me that in his Countrey 't was usual to have wood frozen so hard that the Hatchets would not cut it but rebound from it and that 't was very usual to hear in the night a great many loud cracks almost like the reports of Pistols of the shingles or wooden tyles wherewith in many places they cover their houses instead of Slate and this as I purposely ask'd when the weather was dry and excessively cold When I likewise inquir'd about the thawing of wood he told me he had several times seen pieces of Timber which having been throughly frozen in the Air did when brought into rooms made warm by Stoves become cover'd with a kind of hoar frost and made them look white and that though his Bow which he shew'd me were very strong and tough as being made not of wood but horn and other close materials it would be so chang'd by the frost that unless special care were had in the thawing of it it would break That Marle and Chalk and other less solid terrestrial Concretions will be shatter'd by strong and durable frosts is observ'd by Husbandmen who thereby find it the better fitted to manure their land the Texture of those bodies during whose intireness the parts most proper to feed grass and corn are more lock'd up being by congelation in great part dissolv'd but that true and solid stones wont to be imploy'd in noble and durable Buildings should be spoil'd by the frost will perhaps to most readers seem very improbable And therefore I shall here add what I have learn'd by inquiry of the ingeniousest and most experienc'd Mason I have met with because it may not only surprize most readers but prove an useful observation to him Having then inquir'd of this Tradesman whether he did not find that some free stone a name vulgarly known would not be spoil'd by the frost he told me that he had often observ'd both free stone and harder stones then that to be exceedingly spoil'd by the frost and reduc'd to crack or scale off to the blemishing and prejudice of the houses that are built of them But because it may be objected against this that experience shews us that divers of the stateliest Fabricks in England have these stones for their chief materials and yet indure very well the inclemencies of the Air the reply may be that the difference may not consist in the peculiar natures of the stones imploy'd but in the several seasons in which the same kind of stones are digg'd out of the Quarry For if they be digg'd up when the cold weather is already come in and imploy'd in building the same Winter they will upon very hard frosts be apt to be shatter'd or scale but if they be digg'd early in the Summer and suffer'd to lye expos'd to the Sun and Air during all the heat of the Summer these season'd stones if I may so call them may outlast many sharp Winters unimpair'd It seems to me worth trying whether during their insolation if that term may be allow'd me there do not by the operation of the heat and air upon them exhale a certain unripe mineral sap or moisture whose recess may perhaps be discover'd by weight which if it remain in the stone may by very piercing frosts be congeal'd almost like the sap in Timber-trees and shatter the Texture of the stone which agrees well with what was told me by an understanding person that is Master of a great Glass-house of whom having purposely inquir'd whether he did
not find that his great earthen pots which are made up with as little water as is possible are deservedly famous for their durable Texture had not that Texture alter'd and impair'd by very piercing frosts he assur'd me that if he did not take care to keep the frost as they speak from getting into them those great and solid vessels wherein he us'd to keep his glass in fusion would in the fire scale or crack and perhaps fly and become unserviceable no less then some weeks sooner then if they had never been impair'd by the frost And when I inquired whether also glass it self would not be much prejudiced thereby he affirmed to me that oftentimes in very hard frosts many glasses that had continued intire for many weeks for that circumstance I was sollicitous to ask about would as it were of their own own accord crack with loud noises But whatever prove to be the issue of such Trials it will not be amiss to confirm the Phaenomenon it self by the testimony of an illiterate but very experienc'd French Aurhor who on a certain occasion tells us as I also take notice in another Treatise That he knows the stones of the mountains of Ardenne famous enough in France are harder then Marble and yet the inhabitants of that Countrey do not draw them out of the Quarry in winter because they are subject to the frost And it has been divers times seen that upon thaws the rocks without being cut have fallen down and kill'd many But it may yet seem far more unlikely that frosts should get into mettals themselves and yet having ask'd the newly mention'd Polonian whether he had observ'd any thing of that kind he answer'd that he had often by drawing out his sword and pulling out his pistols when he had been long in the field and came into a hot room found them quickly almost whitened over by a kind of small hoar frost But whether this were as he conceiv'd any thing that was drawn out of the Steel and setled on the surface of it I want circumstances enough to make me willing to determine But if we will credit Olaus Magnus it must be confess'd that considerably thick pieces of Iron and Steel it self will in the Northern Regions be render'd so brittle by the extreme frost that they are fain to temper their instruments after a peculiar manner his words which being remarkable I forbear to alter are these Videntur praeterea ferrei ligones certa ratione fabricati quia his spissa atque indurata glacies caeteris instrumentis ferreis non cedens facilius infringitur dum aliae secures chalybe permixtae in vehementi frigore ad solum glaciei vel virentis arboris ictum instar vitri rumpuntur ubi ligones praedicti sive ferreae hastae fortissimi manent Which testimony notwithstanding what some have written to this Authors disparagement does not seem to me at all incredible For I remember that even here in England I have had the curiosity to cause trials to be made in very frosty weather whereby if an expert Smith I then us'd to imploy did not gratis deceive me in the Irons I imploy'd that 〈◊〉 may by such degrees of cold as even our Climate is capable of be rendered exceeding brittle as he several times affirm'd to me that there are some kinds of iron which he could hammer and turn as they phrase it cold in open weather which yet in very hard frosts would become so brittle as by the same way of working easily to break if not to flye asunder And this he affirm'd both of Iron and Steel of which latter mettal another very skilful workman whom I also consulted certifi'd the like but though this disagreed not with trials purposely made on Iron rods had inform'd me yet presuming that in such a nice piece of work as a spring some further satisfaction about this matter might be obtain'd I inquired of a very dexterous Artificer that was skill'd in making springs for others whether or no he found a necessity of giving springs another temper in very frosty weather then at other seasons and he answered me that in such 〈◊〉 if he gave his springs the same temper that he did in mild and open weather they would be very apt to break And therefore in very sharp seasons he us'd to take them down lower as they speak that is give them a softer temper then at other times which as it makes it probable that the cold may have a considerable operation upon bodies upon which most men would not suspect it to have one so that discovery may afford a hint that may possibly reach further then we are yet aware of touching the interest that cold may have in many of the Phaenomena of nature I should here subjoyn that in prosecution of what is deliver'd in the XX. Section about the weight of solid bodies that I there wish'd might be expos'd to a congealing Air I did cause some Trials of that kind to be made in a very frosty night especially with Bricks but something that happened to the only Scales I then had fit for such an Experiment made me doubt whether some little increase of weight that seem'd to be gain'd by congelation were to be reli'd upon though there did not appear any hoar frost or other thing outwardly adhering to which the effect could be ascrib'd It is a Tradition which the Schools and others have receiv'd with great veneration from their Master Aristotle that hot water will sooner freez then cold but I do not much wonder that the learned 〈◊〉 as I find him quoted by Bartholinus should contradict this Tradition though he be himself a commentator upon that Book of Aristotle wherein 't is deliver'd For I could never satisfie my self that there is at least with our water and in our Climate any truth in the Assertion though I have made trial of it more ways then one but it may very well suffice to mention a few of the plainest and easiest Trials with whose success I am well satisfi'd as to the main as the Reader also will I doubt not be though not having for want of health been able to have so immediate an inspection of these as of the rest of my Experiments I was sometimes fain to trust the watchfulness of my servants whom I was careful to send out often to bring me word how long after the first freezing of the cold water it was before the other began to be congeal'd We took then three pottingers as near of a size as we could and the one we fill'd almost to the top with cold water the other with water that had been boil'd before and was moderately cool'd again and the third with hot water these three vessels were expos'd together in the same place to the freezing Air. In the Entry of one of the Trials I find that being all three put out at half an hour after eight of the clock That the
Criterion then the bare touch to judge of the coldness of liquors these being reduc'd to the same temper were expos'd to a very sharp Air and there watch'd by the person whom being not well and unable to support such weather my self I appointed to attend the Experiment and he according to direction finding them begin to freez as 't were at the very same time brought me in the two pottingers in each of which I saw the beginnings and but the beginnings of congelation where the upper surfaces of the waters were contiguous to the containing vessels so that having made this Experiment with much greater exactness then probably Berigardus did or for want of such instruments as I us'd could make it I cannot but suspect supposing the common waters he and I us'd to be of the same nature that he was either negligent or over-seen in affirming that heated and refrigerated water will cool so much sooner as he would perswade us then other And as I am not convinc'd by experience that it will freez sooner at all so till he have better made out the reason he seems to give of the Phaenomenon I must question whether he rightly ascribe after Cabaeus if I much misremember not the congelation of water to a certain Coagulum distinct from the cold spirits that plentifully mingle with the water which Coagulum it seems for his style is not wont to be very perspicuous that he would have to consist of certain dry Corpuscles no less necessary to conglaciate water then Runnet to curdle Milk And for what this Author says that he must have imploy'd boiling or scalding water who affirms it to be less congealable then other that mistake may be sufficiently disprov'd by the several above recited Trials wherein we found water moderately refrigerated to freez much later then cold and whereas Berigardus intimates that the person whoever he be that he dissents from does unskilfully suppose warm salt-water to be the less dispos'd to congelation for being salt our Author is therein also mistaken for though it be true what he alledges that salt outwardly appli'd promotes the congelation of water yet that dissolv'd in water it has a contrary effect may appear by the familiar observation that Sea-water is much more difficult to be congeal'd then fresh water and to show that 't is not a property of Sea-water but a water impregnated with common Salt I have several times tri'd that a strong solution of such salt in ordinary water will not at all be congeal'd by the being expos'd to the Air even in very sharp frosts as may be easily collected from some of the Experiments mention'd in the former part of this Book Another particular there is about the use of Allume in reference to freezing in this often cited passage of Berigardus which I might here examine if my hast and my indisposedness to ingage in a controversie of small moment did not injoyn me to defer it till a fitter occasion To confirm the power ascrib'd in the VI. Section to cold as to the long preservation of bodies from corruption 't will not be amiss to add these two remarkable passages the latter of which affords a good instance of the improvement that may be made of some degrees of cold to the uses of humane life The first observation is afforded us by some of our Countrey-men in a Voyage extant in Purchas where the writer of it speaks thus Of the Samojeds whose Countrey he visited Their Dead they bury on the side of the hills where they live which is commonly on some small Islands making a pile of stones over them yet not so close but that we might see the dead Body the Air being so piercing that it keepeth them from much stincking savour so likewise I have seen their Dogs buried in the same manner The other observation is given us in the description of Iceland made by one that visited it to be met with in the same Purchas's Collections where among other things he gives us this Account which if I mistake not I have had confirm'd by others of their strange way of ordering and preserving their Fish Having taken them they pluck out the bones and lay up their bowels and make Fat or Oyl of them They heap up their Fish in the open Air and the purity of the Air is such there that they are hardned only with the Wind and Sun without Salt better surely then if they were corned with Salt And if they kill any Beast they preserve the flesh without stinck or putrefaction without Salt hardned only with the Wind. I know not whether 't will be worth while to add to the fifth and sixth Numbers of the VII Title that for further confirmation of our opinion that 't is not Natures abhorrencie of a Vacuum but the distension of the water that breaks glasses when the contain'd liquors come to be congeal'd I did on set purpose fill several vials some at one time and some at another to the lower parts of their necks most of which were purposely made long with common water and though they were all left unstopp'd that the external Air might come in freely to them yet not only one of them that I stirr'd up and down in a mixture of beaten ice salt and water was hastily broken upon the congelation of the contain'd water but several others that were expos'd to be frozen more leisurely by the cold Air only were likewise broken to pieces by the expansion of the freezing water as appear'd both by the gaping cracks and also by this that the ice was considerably risen in the necks above the waters former stations which had been noted by marks before and if it had been more easie for the included water to make it self room either by stretching the glass or rather leaving the superficial ice congeal'd at first in the neck or by both those ways together then to break the vessel the vial would probably have remained intire I say probably because I am not sure that there may not sometimes intervene in these Experiments somewhat that may need further observation and inquiring For as it seems that what I have been lately saying may be confirmed by an unstopp'd vial which was expos'd at the same time to congelation with this success that without breaking the vial the water was frozen and the ice in the neck impell'd up a good way above the height at which the liquor rested before it began to congeal so on the other side I remember that I have sometimes had a good store of liquor frozen in a vial without breaking the glass though a vial were stopp'd as if the difference that I have on other occasions observed betwixt glasses whereof some are very brittle and others more apt to yield might have an influence on such Experiments or that some peculiar softness or other property of the ice that afforded me my observation or else some other thing not yet
taken notice of were able to vary their success In confirmation of what is delivered in the VII Section about the expansion of water by freezing I shall add that having caus'd some strong glass-Bottles of a not inconsiderable bignéss to be fill'd with a congealable liquor excepting the necks which were fill'd with Sallet oyl I observ'd that in a somewhat long and very sharp frost the contained water was so far expanded by congelation that it not only thrust up the corks but the cold having taken away the defluency of the oyl that liquor together with the water that could no longer be contain'd in the Cavities of the glasses being as it seem'd frozen as fast as it was thrust out of the neck there appear'd quite above the upper part of the Bottles Cylinders of divers inches in height consisting partly of concreted oyl and partly of congeal'd water having on their tops the corks that had been rais'd by them It is a Tradition very currant among us that when Ponds or Rivers are frozen over unless the ice be seasonably broken in several places the Fishes will dye for want of Air. And I find this Tradition to be more general then before I made particular inquiry into it I knew of For Olaus Magnus mentions it more then once without at all questioning the truth of it but rather as if the general practise of the Northern Nations to break in divers places their frozen Ponds and Rivers were grounded upon the certainty of it In the twentieth Book which treats of Fishes after having spoke of the reasons why the Northern Fishermen imploy so much pains and industry to fish under the ice and having said among other things that the nature of the Fish exacts it he adds this reason that Nisi glacie perforata respiracula susciperent quotquot in flumine vel stagno versantur subito morerentur Another passage of the same Author and taken likewise out of the same 20. Book you may meet with in the Margent though in another place he seems to intimate another and not an absurd reason of the death of Fishes in Winter where advertising the Reader that Ponds and Lakes did generally begin to freez in October he adds that Fishes are usually found suffocated when the Thaw comes where veins or springs of living water do not enter by which passage he seems to make the want of shifted water cooperate to the suffocation of the Fishes And to the same purpose I shall now add that having inquir'd of a learned Native that had had about Cracovia whose Territory is said to abound much in Ponds whether the Polanders also us'd the same custome he answered me that they did and that sometimes in larger Ponds they were careful to break the ice in eight or ten several places to make so many either vents or Air-holes for the preservation as they suppos'd of the Fish And when I inquir'd of the often mention'd Russian Emperors Physician whether in Muscovy the frost kill'd the Fishes in the Ponds in case the ice were not broken to give them Air he answered that in ordinary Ponds it were not to be doubted but that in great Lakes he could not tell because the Fishermen use to break many great holes in the ice for the taking of the Fish For at each of these holes they thrust in a Net and all these Nets are drawn up together in one great breach made insome convenient place near the middle of the rest It appears then that the Tradition is general enough but whether it be well grounded I dare not determine either affirmatively or negatively till trial have been made in Ponds with more of design or of curiosity and watchfulness then I have known hitherto done men seeming to have acquiesc'd in the Tradition without examining it and to have been more careful not to omit what is generally believ'd necessary to the preservation of their Fish then to try whether they would escape without it Wherefore though for ought I know the Tradition may prove true yet to induce men not to think it certain till experience has duly convinc'd them of it I shall represent That as much as I have in other Treatises manifested how necessary Air is to Animals yet whether Fishes may not live either without Air or without any more of it then they may find interspers'd in the water they swim in has not yet that I know of been sufficiently prov'd For what we have attempted of that nature in our Pneumatical Engine whether it be satisfactory or not is not yet divulged And I remember not to have hitherto met with any writer except Olaus be construed to intimate so much that affirms upon his own observation that the want of breaking ice in Ponds has destroy'd all the Fish Besides that possibly in frozen Ponds there may be other reasons of the death of the Fishes that are kill'd if any store of them be so by very sharp frosts For who knows what the locking up of some kinds of subterraneal steams that are wont freely to ascend through water unfrozen may do to vitiate and infect the unventulated water and make it noxious to the Fishes that live in it perhaps also the excrementitious steams that insensibly issue out of the bodies of the Fishes themselves may by being penn'd up by the ice contribute in some cases to the vitiating of the water at least in reference to some sort of Fishes For being desirous to learn from a person curious of the ways of preserving and transporting Fish whether some Fishes would not quickly languish grow sick and sometimes dy out-right if the water they swam in were not often shifted he assur'd me that some kinds of them would and it has not yet that I hear of been tri'd whether or no though Ponds seldom freez to the bottom yet the water that remains under the ice in which it self some Fishes may be now and then intercepted may not even whilest it continues uncongeal'd admit a degree of cold that though not great enough to turn water into ice may yet be great enough when it continues very long to destroy Fishes though not immediately yet within a less space of time then that during which the surface of the Pond continues frozen But 't is not worth while to be sollicitous about conjectures of causes till we are sure of the Truth of the Phaenomenon and these things are propos'd not so much to confute the Tradition we have been speaking of as to bring it to a Trial which having no opportunity to make in Ponds I endeavour'd as well this Winter as formerly to obtain what information I could from Trials made in small vessels with the few Fishes I was able to procure And I shall subjoyn most of these Trials not because I think them very considerable but because they are for ought I know the only attempts of the kind that have yet been made To satisfie my self whether the ices denying
should have made more Trials at least if not also more satisfactory ones if I could have had Fishes and vessels and cold weather at command But upon the whole matter though the Tradition we have been examining may perhaps have some thing of truth in it yet it seems to deserve to be further inquired into both in reference to the truth of the matter of fact the death of Fishes in frozen Ponds and Rivers and in reference to the cause whereto that effect is imputed I met with an odd passage in Captain James's voyage which if it had been circumstantially enough set down might prove of moment in reference to the weight of bodies frozen and unfrozen and therefore though I would not build any thing on it yet I shall not omit it The ninth says he we hoisted out our Beer and Cydar and made a Raft of it fastning it to our shore-Anchor The Beer and Cydar sunck presently to the ground which was nothing strange to us for that any wood or pipe-staves that had layen under the ice all Winter would also sinck down so soon as ever it was heav'd over board About the duration of ice I forgot through hast to add a relation of Capt. James whereby it may appear That though Wine abounds with very spirituous and nimble parts whence it resists congelation far more then water yet if even this liquor came once to be congeal'd the ice made of it may be very durable For he sets down in his Journal that when he came to his Ship again he found a But of Wine that had been all the Winter in the upper deck to continue as yet all firm frozen though it were then the moneth of May. When I treated of the great proportion in some pieces of ice that were aground instead of taking notice of the great piece of ice mention'd by Gerard de Veer to be 52. fathom deep the passage that was to be transcrib'd was this other hard by which contains two examples of towers of ice where the extant part reach'd upwards more then half as much as the immersed part reach'd downwards We saw says he another great piece of ice not far from us lying fast in the Sea that was as sharp above as if it had been a Tower whereunto we rowed and casting out our lead we found that it lay 20. fathom fast on the ground under the water and 12. fathom above the water We rowed to another piece of ice and cast out our Lead and found that it lay 18. fathom deep fast on the ground under the water and 10. fathom above the water That snow lying long and too long on the ground does much conduce to the fertilizing of it is a common observation of our Husbandmen And Bartholinus in his Treatise of the use of snow brings several passages out of Authors to make it good to which I shall add the testimony of our learned English Ambassador Dr. Fletcher who speaking of the fruitfulness of the soil and hasty growth of many things in the great Empire of Russia gives this account of it This fresh and speedy growth of the Spring there seemeth to proceed from the benefit of the snow which all the Winter time being spread over the whole Country as a white robe and keeping it warm from the rigour of the frost in the Spring time when the Sun waxeth warm and dissolveth it into water doth so throughly drench and soak the ground that it is somewhat of a slight and sandymold and then shineth so hotly upon it again that it draweth the herbs and plants forth in great plenty and variety in a very short time As we made some Trials to discover whether congelation would destroy or considerably alter the odors of bodies so we had the like curiosity in reference to divers other qualities not only those that are reputed manifest as colours and tastes the latter of which we sometimes found to be notably chang'd for the worse in flesh congeal'd but also those that are wont to be call'd occult and among the qualities of this sort I had particularly a mind to try whether the purging faculty of Catharticks would be advanc'd or impair'd or destroy'd by congelation and for this purpose I caus'd to be expos'd thereunto divers purging liquors some of a more benigne and some of a brisker nature and that in differing forms as of syrup decoction infusion c. But for want of opportunity to try upon the bodies of animals what change the cold had made in the purging liquors it had congeal'd I was unable to give my self an account of the success of such Experiments only since in some of these Trials I had a care to make use of Cathartick liquors prepar'd by fermentation which way of preparing them is it self a thing I elsewhere take notice of as not unworthy to be prosecuted I shall add on this occasion that fermentation is so noble and important a subject that the influence of cold upon it may deserve a particular inquiry And I am invited to think that that influence may be very considerable partly by my having observ'd upon a Trial purposely made both that Raisins and water with which I was us'd to make Artificial Wines did not in many days whilest the weather was very frosty so much as manifestly begin to ferment though the water were kept fluid and partly by my having observ'd that Beer will continue as it were new and be kept from being as they call it ready to drink much longer then one would readily suspect if very frosty weather supervene before it have quite finished its fermentation insomuch that an experienc'd person of whom I afterwards inquir'd about this matter assur'd me that Beer not duly ripe would not sometimes in five or six weeks of very frosty weather be brought to be as ripe as in one week of warm and friendly weather But we have a nobler instance to our present purpose if that be true which I learn'd from an intelligent Frenchman whom I consulted about this matter For according to this experienc'd person the way to keep Wine in the Must in which state its sweetness makes it desir'd by many is to take newly express'd juice of Grapes and having turn'd it up before it begins to work to let down the vessels which ought to be very carefully clos'd to the bottom of some deep Well or River for six or eight weeks during which time the liquor will be so well setled if I may so speak in the constitution it has so long obtain'd that afterwards it may be kept in almost the same state and for divers moneths continue a sweet and not yet fermented liquor which some in imitation of the French and Latins call in one word Must. And how by the help of Cold well appli'd some other juices that are wont to work early and to be thereby soon spoil'd may be long kept from working the Reader may perchance learn in
another Treatise to which such matters more properly belong 'T is known that the Schools define cold by the property they ascribe to it of congregating both Heterogeneous and Homogeneous things I thought it not amiss to attempt the making some separations in bodies by the force of Cold. For if that hold true in this climate which has been observ'd by Travellers and Navigators in Northern Regions that men may obtain from Beer and Wine a very strong spirit and a phlegme by congelation it seems probable that in divers other liquors the waterish part will begin to freez before the more spirituous and saline and if so we may be assisted to make divers separations as well by cold as by heat and dephlegme if I may so speak some liquors as well by congelation as by distillation but I doubt whether the ordinary frosts of this Countrey can produce a degree of cold great enough to make such divisions and separations in bodies as have been observ'd in the more Northern Climates For though having purposely hung out a glass-bottle with a quart of Beer in it in an extraordinarily sharp night I found the next morning that much the greatest part of the Beer being turn'd into ice there remain'd somewhat nearer the middle but nearer the bottom an uncongeal'd liquor which to me and others seem'd stronger then the Beer and was at least manifestly stronger then the thaw'd ice which made but a spiritless and as it were but a dead drink yet in some other Trials my success was not so considerable as some would have expected For having put one part of high rectifi'd spirit of Wine to about five or six parts if I misremember not of common water and having put them into a round glass and plac'd that in beaten ice and salt though the mixture were in great part turn'd into ice yet I could not perceive that even two liquors so slightly mingled were any thing accurately severed from one another although once to enable my self the better to judge of it the spirit of Wine I imploy'd was beforehand deeply tincted with Cochinele and therefore I the less wonder that in Claret Wine I could not make any exact separation of the red and the colourless parts However I thought it not amiss to try how far in some other liquors this way of separating the waterish and more easily congealable part from the rest would or would not succeed And I remember that a large glass vessel wherein spirit of Vinegre was exposed to the cold a considerable part was turned into ice whose swimming argued it to be lighter then the rest of the liquor but though I put some of this ice in a glass by it self to examine by its weight and taste when thaw'd how much it differ'd from the uncongeal'd part of the spirit my hopes were disappointed by a misfortune which was not repaired by my exposing afterwards a smaller quantity of spirit of Vinegre to the Nocturnal Air for that proved so cold that the whole was turned into ice wherefore I must reserve for another opportunity the prosecuting that Experiment as also the trying whether a separation of the Serous or the Oleaginous parts of Milk may be effected For though once the frost seem'd to have promoted a separation of Creme notwithstanding that heat also may do it and though another time there seem'd to be another kind of divulsion of parts made by congelation yet for want of leisure to prosecute such Trials they prov'd not satisfactory no more then did some attempts of the like nature that I made upon blood by freezing it But notwithstanding these discouragements I resolv'd to try what I could do upon Brine For calling to mind the Relations mentioned in the XV. Title and elsewhere which seem to argue that in some cases the ice of the Sea-water may being thaw'd yield fresh water and being the more inclin'd to think it worth Trial by a Physician I since happened to discourse with about this matter who affirm'd to me that sailing along the coast of Germany he had taken out of the Sea ice that being thaw'd he found to afford good fresh water I began to consider whether we might not by cold free salt water at some seasons of the year from a great deal of the phlegme which 't is wont to cost much to free them from by fire and other means For a little help towards the diminution of the fresh water is look'd upon as so useful an Experiment by many that boil salt out of the salt springs that in some Countries that are thought the skilfullest in that trade they make their salt-salt-water fall upon great bundles of small brush-wood that being thereby divided and reduc'd to a far greater superficies there may in falling through some of the purely Aqueous parts exhale away wherefore dissolving one part of common salt in 44. times its weight of common water that it might be reduc'd either exactly or near to the degree of saltness that has been by several writers observed in the water of our neighbouring Seas and having likewise caus'd another and much stronger Brine to be made by putting in to the water a far greater proportion of salt for so there is in many of our salt springs we expos'd these several solutions to the congealing cold of the Air in frosty weather where the last mention'd solution being too strongly impregnated with the salt continued some days and nights altogether uncongeal'd but that weaker solution which emulated Sea water being expos'd in a shallow and wide mouth'd vessel that shape being judg'd the most proper we could procure for our design the large superficies that was expos'd to the Air did as we expected afford us a cake of ice which being taken off and the rest of the liquor expos'd again to the Air in the same vessel we obtain'd a second cake of ice and taking the remaining which seem'd to be indispos'd enough to congelation we found that by comparing it with that which was afforded us by the first cake of ice permitted to thaw there appear'd a very manifest difference betwixt the water whereinto the ice was resolv'd scarce tasting so much as brackish whereas the liquor that had continued uncongeal'd was considerably salt in taste And if I had had the conveniency of examining my self these two liquors Hydrostatically as I was fain to have them examin'd by another I doubt not but by their weight I should have discovered precisely enough the difference between them which the person I employ'd found to be considerable and consequently should have been assisted to make an estimate of the advantage that might be afforded by the operation of the cold towards the freezing of the Brine from its superfluous water But though I had not a quantity of ice great enough to satisfie me whether that little brackishness of taste I have mention'd proceeded from some saline Corpuscles that concurr'd to the constituting of the ice it self or did only adhere
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
having imagin'd that Cold might afford a hopefuller way then for ought I know any man has us'd of bringing this controversie to the dicision of an Experiment I made that attempt that is mention'd in the XII Title in prosecution of which as soon as I could procure some though but some of the accommodations which I long wanted I made an Experiment which I shall subjoyn because though it be not so considerable as with better implements I could have made it yet the way I chose has as I partly intimated elsewhere these two advantages that the force imploy'd to compress the Air is both very great and very gradually and slowly appli'd and that the vessel will not like those that have been hitherto made use of give any passage through its pores to water though violently compress'd We took then a Round Ball of glass furnish'd with a moderately long Pipe and having fill'd it with water till the liquor reach'd within some inches of the top it was Hermetically seal'd up and then the water by a mixture of beaten ice and salt was made to freez from the bottom upwards that without breaking the glass the unfrozen water by the expansive endeavour of that which was freezing might be impell'd upwards and so at once both compress the Air and be press'd upon by it having by this means condens'd the Air as far as we thought safe to do in a glass that was not strong we cropt of the small Apex of the glass and immediately the compress'd Air flew out with a great noise and that part of the Pipe which was unfill'd with water was fill'd with smoak that made it look white and great store of little bubbles hastily ascended from the lower parts of the water to the upper where most of them quickly broke in such a way as put me in mind of what usually happens upon the opening of vessels that contain'd bottled Beer But that which was principally to be noted was this that besides the bubbles or froth the water it self at least supposing that no little unheeded bubbles that did not quite emerge could sensibly contribute to its height immediately ascended in the Pipe about ¾ of an inch which having carefully mark'd the first and second stations with a Diamond on the outside of the glass 't was easie for us to measure I have elsewhere propos'd a suspicion that in the attempts that had been till then made to compress water the condensation in case there were really any might perchance proceed from the compression of the Aerial particles that I have shown to be wont to ly dispers'd in the pores of common water But though the considerable expansion of water notwithstanding the breaking of the bubbles in our present Experiment seems manifestly to argue that this could be but a concurrent cause if it had any sensible effect at all of our Phaenomena yet I dare not absolutely rely even upon an Experiment that seems so cogent till I have satisfi'd my self that no springiness which I have sometimes suspected might be in the ice had any interest in the produc'd effect and that the great pressure of the forcibly condens'd Air did not make the glass it self stretch or yield For if it were able to do so then the parts of the violently distended glass upon the removal of the forcible pressure of the Air which must cease upon the breaking of the Hermetical seal returning to their former straitness below will make the water ascend somewhat higher in the pipe But though I could not procure glasses as well very thick as conveniently shaped wherewith to examine this suspicion which I would likewise have tri'd by the bulk of the glass in water before and after the letting out of the compress'd Air yet because most Readers will probably think so much caution more then necessary I shall add that if I had not wanted conveniencies and had not had mischances the Experiment would in likelihood have been advanc'd especially care being taken that the Air left in the pipe should be well refrigerated before its being seal'd up as we sometimes did by ice and salt applied in a perforated Box to the outside lest part of its spring should depend upon an evanid degree of heat upon which account the pipe ought beforehand to be drawn so slender that the glass may be melted together in a trice For though for want of strong glasses the best sort of instruments to seal up such with the success was not still so considerable as I hop'd for yet as 4. or 5. other Trials made as well with another liquor as with water did exhibit a manifest intumescence of the liquors without computing the froth produc'd at the top so in the Experiment lately mention'd if we had judg'd them strong enough to indure such a compression of the included Air as we have often made on other occasions the effect would probably have been much more considerable For though the difference betwixt the length of the same water compress'd and uncompress'd amounted to an Aqueous Cylinder of ⅜ of an inch in height yet the Air that made this compression of the water was it self reduc'd but from 8. inches to 5. so that it took up almost half its former room whereas we have sometimes reduc'd it to an 18. or 20. part thereof If I had been accommodated with one of my Pneumatical Engines I should have tri'd whether water being first carefully freed from the latitant Air in the exhausted Receiver and then compress'd after the manner hitherto recited the event of the Trial would have been considerably varied I might add as other Phaenomena of our Experiment that when we broke off the seal'd Apex of the glass before the included Air was much compress'd there neither 〈◊〉 be any great noise made nor any considerable froth produc'd at the top of the water and that having had the curiosity to repeat the Experiment in one of the same glasses 〈◊〉 had been 〈◊〉 us'd and with the same 〈◊〉 that had been already compress'd in it we found that upon the breaking off the Hermetical seal the second time the water did nevertheless ascend in the Pipe betwixt ⅛ and ¼ part of an inch And to these particulars I could both add other circumstances that I took notice of in the same Experiment and subjoyn many other Experiments and Observations but that I am already tyr'd And though I have not found Cold to be a subject over-fruitful in Experiments Pleasing and Curious yet now I am grown somewhat acquainted with it I find it may suggest so many other new ones that since the Barrenness of my Theme will not easily put a period to this Treatise 't is fit that now at length I should let my Weariness and want of Leisure do it FINIS AN Examen of Antiperistasis AS It is wont to be Taught and Prov'd Themistius Carneades Eleutherius Themistius 1. AS for Antiperistasis the Truth of it is a thing so conspicuous and
so generally acknowledg'd that I cannot imagine what should make some men deny it except it be that they find all others to confess it For though in other cases they are wont to pretend Experience for their quitting the receiv'd Opinions yet here they quit Experience it self for singularity and chuse rather to depart from the Testimony of their senses then not to depart from the Generality of Men. 2. And to evince that this is not said gratis I might observe to you That there are no less then three grand inducements that have lead both the Vulgar and Philosophers two sorts of men that seldom agree in other things to consent in the acknowledgment of Antiperistasis Authority Reason and Experience But though I think fit to name them all three yet since the first of them by having as I just now noted invited our Adversaries to dissent from the Truth is a somewhat unlikely Medium to prevail on them to acknowledge it I shall insist only on the two latter having once declar'd that I lay aside the first not as worthless in it self but needless to my cause 3. To begin then with the Arguments afforded us by Reason What can there be more agreeable to the wisdom and goodness of Nature who designing the Preservation of things is wont to be careful of fitting them with requisites for that preservation then to furnish cold and heat with that self invigorating power which each of them may put forth when 't is environ'd with its contrary For the order of the universe requiring that cold and heat should reside in those Bodies that often happen to be mingled with one another those two noble and necessary Qualities would be too often destroy'd in the particular subjects that harboured them if provident Nature had not so ordered the matter that when a Body wherein either of them resides happens to be surrounded by other Bodies wherein the contrary Quality is predominant the besieg'd Quality by retiring to the innermost parts of that which it possesses and there by recollecting its forces and as it were animating it self to a vigorous defence is intended or increased in its degree and so becomes able to resist an Adversary that would otherwise easily destroy it 4. To illustrate as well as supply this Argument drawn from Reason we shall need but to subjoyn the other afforded us by Experience which does almost every day give us not only opportunity to observe but cause to admire the effects of this self invigorating power which when occasionally exerted we call Antiperistasis And these Phaenomena ought the more to be acquiesced in because they may safely be looked upon as genuine Declarations which Nature makes of Her own accord and not as confessions extorted from Her by Artificial and compulsory Experiments when being tortured by Instruments and Engines as upon so many Racks she is forced to seem to confess whatever the Tormentors please 5. To proceed then to the spontaneous Phaenomena of Nature I was recommending we see that whereas in Summer the lowest and highest Regions of the Air are made almost unsufferable to us by their heat the cold expelled from the earth and water by the Suns scorching beams retires to the middle Region of the Air and there defends it self against the heat of the other two though in the one that Quality be assisted by the almost perpendicular reflection of the Sun-beams and in the other it 〈◊〉 rendered very confiderable by the vastness of the upper Region of the Air and its Vicinity to the Element of fire And as the cold maintains it self in the middle Region by vertue of the intensness which it acquires upon the account of Antiperistasis so the Lightning that flashes out of the Clouds is but a fire produc'd in that midle Region by the hot Exhalations penn'd up and intended in point of heat by the ambient Cold to a degree that amounts to ascension 6. But though these be unquestionably the effects of that excessive coldness yet we need not go so far as the tops of mountains to fetch proofs of our doctrine since we may find them at the bottom of our Wells For though Carneades perhaps will not yet the earth as well as the Air doth readily acknowledge the power of Antiperistasis And if the reason above alledged did not evince it our very senses would For as in Summer when the Air about us is sultry hot we find to our great refreshment that the Air in Cellars and Vaults to which the cold then retreats is eminent for the opposite Quality so in Winter when the outward Air freezes the very Lakes and Rivers where their surfaces are expos'd to it the internal Air in Vaults and Cellars in Winter which becomes the sanctuary of heat as in Summer it was of Cold is able not only to keep our Bodies from freezing but to put them into sweats And not only Wells and Springs upon the account of their resting in or coming out of the deepest parts of the earth continue fluid whilest all the waters that are contiguous to the Air are by the excessive cold hardened into ice but the water freshly drawn from such Wells feels warm or at least tepid to a mans hand put into it And as if Nature design'd men should not be able to contradict the doctrine of Antiperistasis without contradicting more then one of their own senses she has taken care that oftentimes the water that is freshly drawn out of the deeper sorts of Wells and Springs should manifestly as I have seen it smoak as if it had been but lately taken off the fire And this may be said without a Metaphor to demonstrate ad ocnlum the reality of Antiperistasis there being no other cause to which this warmth can be attributed then the retiring of the heat from the cold external Air to the lower parts of the earth and water since both these Elements themselves being naturally cold and one of them in the supreme degree the heat we are mentioning is so far from being likely to be generated in so unfit a place that if it were not very great it must be extinguished there by the coldness of the superior Air and that of the inferior parts of the Earth Eleutherius 7. That Carneades may have but one trouble to answer the Allegations to be made in favour of Antiperistasis I hope he will give me leave according to my custom of siding with either party as occasion invites me to add to the familiar Observations mentioned by Themistius some others that are less obvious For I franckly confess to you that when I consider what interest the unheeded dipositions of our own Bodies may have in the estimates we make of the degrees of cold and heat in other Bodies I should not lay much weight upon the Phaenomena that are wont to be urg'd as proofs of Antiperistasis if some instances somewhat less lyable to suspicion did not countenance the doctrine they are urg'd for I know
I must freely 〈◊〉 that though in living creatures and especially in the bodies of the perfecter sorts of Animals I do in divers cases allow arguments drawn from final causes yet where only inanimate bodies are concern'd I do not easily suffer my self to be prevail'd upon by such Arguments Nor is there any danger that Cold and Heat whose causes are so radicated in Nature should be lost out of the World in case each parcel of matter that happens to be surrounded with bodies wherein a contrary quality is predominant were not endowed with an incomprehensible faculty of self invigoration And Nature either does not need the help of this imaginary power or oftentimes has recourse unto it to very little purpose since we see that these Qualities subsist in the world and yet de facto the bottles of Water Wine and other Liquors that are carried up and down in the Summer are regularly warmed by the Ambient Air. And in Muscovy and other cold Northern Countries Men and other Animals have oftentimes their Vital Heat destroyed by the cold that surrounds them being thereby actually frozen to death And I somewhat wonder that the followers of Aristotle should not take notice of that famous Experiment which he himself delivers where he teaches that hot water will sooner congeal then cold For if the matter of fact were true it would sufficiently manifest that the heat harboured in the water is destroyed not invigorated by the coldness of the Air that surrounds it so that Themistius must I fear on this occasion take sanctuary in my observation and to keep Aristotle from destroying his own opinion with his own Experiment had best say as I do that it is not true And though it is not to be denied that white surrounded with black or black with white becomes thereby the more conspicuous yet 't is acknowledged that there is no real increase or intension of either quality but only a comparative one in reference to our senses obtain'd by this Collation Nor does a Pumice-stone grow more dry then it was in the fire or earth by being transferred into the Air or Water and consequently environed with either of those two fluids which Themistius and his Schools teach us to be moist Elements neither will you expect to find a piece of dim glass become really more transparent though one should set it in a frame of Ebony though that wood be so opacous as to be black And whereas 't is commonly alledged as a proof of the power Nature has given Bodies of flying their contraries that drops of water falling upon a Table will gather themselves into little globes to avoid the contrary quality in the Table and keep themselves from being swallowed up by the dry wood the cause pretended has no interest in the effect but little drops of water where the gravity is not great enough to surmount the action of the ambient fluid if they meet with small dust upon a Table they do as they roul along gather it up and their surfaces being covered with it do not immediately touch the board which else they would stick to And to show you that the Globular figure which the drops of water and other Liquors sometimes acquire proceeds not from their flying of driness but either from their being every way press'd at least almost equally for in some cases also they are not exactly round by some ambient fluid of a disagreeing Nature or from some other cause differing from that the Schools would give I shall desire you to take notice that the drops of water that swim in Oyl so as to be surrounded with it will likewise be Globular and yet Oyl is a true and moistening liquor as well as water And the drops of Quicksilver though upon a Table they are more disposed then water to gather themselves into a round figure yet that they do it not as humid Bodies is evident because Quicksilver broken into drops will have most of them Globular not only in Oyl but in Water And to show you that 't is from the incongruity it has to certain bodies that its drops will not stick upon a Table nor upon some other bodies but gather themselves into little sphaeres as if they designed to touch the woodden Plain but in a Point To manifest this I say we need but take notice that though the same drops will retain the same figure on Stone or Iron yet they will readily adhere to Gold and lose their Globulousness upon it though Gold be a far drier body then Wood which as far as distillation can manifest must have in it store of humid parts of several kinds I mean both watery and unctuous But this may relish of a digression my task being only to examine the Antiperistasis of cold and heat concerning which I think I had very just cause to pronounce the vulgar conceit very unconsonant to the nature of inanimate beings For the Peripateticks talk of Cold and Heat surrounded by the opposite quality as if both of them had an understanding and foresight that in case it did not gather up its spirits and stoutly play its part against the opposite that distresses it it must infallibly perish and as if being conscious to its self of having a power of self invigoration at the presence of its Adversary it were able to encourage it self like the Heroe in the Poet that said Nunc animis opus est Aenea nunc pectore firmo which indeed is to transform Physical agents into Moral ones 12. Eleuth The validity of the Peripatetick Argument drawn from Reason considered abstractedly from Experience I shall leave Themistius to dispute out with you at more leisure And since you well know that the only Arguments I alledge to countenance Antiperistasis were built upon Experience as judging them either the best or the only good ones I long to hear what you will say to the Examples that have been produced of that which you deny 13. Carneades That Eleutherius which I have to answer to the examples that are urged either by the Schools or by you in favour of Antiperistasis consists of two parts For first I might show that as reason declares openly against the common Opinion so there are Experiments which favour mine and which may be opposed to those you have alledged for the contrary doctrine And secondly I might represent that of those examples some are false others doubtful and those that are neither of these two are insufficient or capable of being otherwise explicated without the help of your Hypothesis But for brevities sake I shall not manage these two replies apart but mention as occasion shall serve the Experiments that favour my opinion among my other answers to what you have been pleased to urge on the behalf of Aristotle 14. To begin then with that grand Experiment which I remember a late Champion for Antiperistasis makes his leading Argument to establish it and which is so generally urged on that occasion
and that it was no candle though she had so confidently thought it one that she call'd out to the party she presum'd it to be carried by I will leave Themistius to unriddle how the Nocturnal Air could kindle a fiery Meteor by its coldness and at the same time congeal the falling drops of water into ice by its warmth and shall only add that I doubt not but other observations of the like kind have been often made though perhaps seldom recorded For within the compass of a very few weeks of the storm some servants of mine affirm'd themselves to have observed it to Hail two or three times besides that already mention'd 27. Next if Aristotle have rightly assign'd the cause of Hail 't is somewhat strange it should not fall far more frequently in Summer and especially in hot Climates then it does considering how often in all probability the drops of rain fall cold out of the second Region into the warm Air of the first And more strange it is That even in those parts of Aegypt where it rains frequently enough and plentifully for so Prosper Alpinus that liv'd long there assures us it does though not about Grand Cairo yet about Alexandria and 〈◊〉 sium it should never Hail no more then Snow as the same learned Physician a witness above exception affirms Besides whereas it is pretended that Snow is generated in the upper Region of the Air and Hail always in the lower my own observation has afforded me many instances that seem to contradict the Tradition For I have observed in I know not how many great grains of Hail that besides a hard transparent icy shell there was as 't were a snowy Pith of a soft and white substance and this snowy part was most commonly in the middle of the icy which made me call it Pith but sometimes otherwise And lastly whereas the favourers of Antiperistasis would have the Drops of rain in their descent to be congeal'd apart in the ambient Air not to urge how little the irregular and Angular figures we often meet with in Hail does countenance this doctrine Hail often falls in grains too great by odds to be fit to comply with Aristotles conceit For not to mention the grains of Hail I have observed my self to be of a bigness unsuitable to this opinion divers learned eye-witnesses have inform'd me of their having observ'd much greater then those I have done and particularly an eminent Virtuoso of unquestionable credit affirm'd both to me and to an Assembly of Virtuosi that he had some years ago at Lyons in France observ'd a shower of Hail many of whose grains were as big as ordinary Tennis-balls and which did the Windows and Tyles a mischief answerable to that unusual bulk And Bartholinus affirms that he himself observ'd in another shower of Hail grains of a more unwonted size a single grain weighing no less then a whole pound But though this it self is little in comparison of what I remember I have somewhere met with in learned Authors yet it may abundantly suffice to disprove the vulgar conceit about the generation of Hail till we meet in these Countries with showers of rain whose single drops prove to be of such a bigness which I presume those that ascribe Hail to Antiperistasis will not easily show us 28. I come now to consider the last and indeed the chiefest example that is given of Antiperistasis namely the coldness of Cellars and other subterraneal Vaults in Summer and their heat in Winter And as the Argument wont to be drawn from hence consists of two parts I will examine each of them by its self 29. And first as to the refreshing coldness that subterraneal places are wont to afford us in Summer I both deny that they are then colder than in Winter and I say that though they were that coldness would not necessarily infer an Antiperistasis 30. We must consider then that in Summer our Bodies having for many days if not some weeks or perhaps months been constantly environ'd with an Air which at that season of the year is much hotter then 't is wont to be in Winter or in other seasons our senses may easily impose upon us and we may be much mistaken by concluding upon their Testimony that the subterraneal Air we then find so cool is really colder then it was in Winter or at the Spring as they that come out of hot Baths think the Air of the adjoyning rooms very fresh and cool which they found to be very warm when coming out of the open Air they went through those warm rooms to the Bath and the deepness and retiredness of these subterraneal Caves keep the Air they harbour'd from being any thing near so much affected with the changes of the season as the outward Air that is freely expos'd to the Suns warming beams which pierces with any sensible force so little a way into the ground that Diggers are not wont to observe the Earth to be dried and discolour'd by them beyond the depth of a very few feet And I have found that in very shallow Mines not exceeding six or seven yards in depth though the mouth were wide and the descent perpendicular enough the Air was cool in the heat of Summer so that the free Air and our Bodies that are always immers'd in it being much warmer in Summer then at other times and the subterraneal Air by reason of its remoteness from those causes of alteration continuing still the same or but very little chang'd it 's no wonder there should appear a difference as to sense when our bodies pass from one of them to another 31. And supposing but not yielding that the Air of Cellars and Vaults were really colder in Summer then in Winter that is were discovered to have a greater coldness not only as to our sense of feeling but as to Weather-glasses yet why should we for all that have recourse for the solution of the difficulty to an Antiperistasis which 't is much harder to understand then to find out the cause of the Phaenomenon which seems in short to be this That whereas which I shall soon have occasion to manifest there are warm Exhalations that in all seasons are plentifully sent up by the subterraneal heat from the lower to the superficial parts of the Earth these steams that in Winter are in great part repress'd or check'd in their ascent by the cold frost or snow that constipates the surface of the Earth and choaks up its pores these Exhalations I say that being detain'd in the ground would temper the Native coldness of the Earth and Water and consequently that of Springs and of the subterraneal Air are by the heat that reigns in the outward Air call'd out at the many pores and chinks which that heat opens on the surface of the ground by which means the water of deep Springs and Wells and the subterraneal Air being depriv'd of that which is wont to allay their Native or wonted
that which makes mainly for my present purpose beginning contrary to vulgar thaws from the bottom upwards 50. And having thus manifested that the lower parts of the Earth do send up great store of Exhalations and Vapours to the upper parts it will be obvious to conceive that as in divers places of the Terrestrial Globe these steams get into the Air either by the advantage of finding vents such as those I have already mentioned or by growing copious enough to force themselves a passage So in most other places where the ascending steams find no commodious vents or are too faintly driven up to gain themselves a passage they must be repress'd or detain'd beneath the surface of the Earth which has its pores in Winter usually choak'd up with snow or rain or its surface constipated and hardened with ice or frost so that these exhalations being pent up and receiving fresh supplies from time to time from beneath 't were no wonder if they should somewhat warm deep Cellars and Wells where they are thus detain'd and therefore our Husbandmen do not speak altogether so improperly when they say that the snow keeps the ground warm And I remember that Dr. Smith the learned English 〈◊〉 into Musco makes it to be one of the principal reasons of the great fertility he justly ascribes to the Country there about that during almost all the Winter the ground is to a great height covered with snow which does not only inrich it by the fertilizing salt which the Earth gains from the snow when that comes to be melted but does also contribute to its improvement by choaking up or obstructing the pores at which the Nitro-sulphureous and other useful Corpuscles that are sent up by the 〈◊〉 heat would easily get away And least Gentlemen you should think that 't is only by the Ratiocination that I conclude that there is really great store of warm steams detain'd under ground in the Winter I shall add this sensible observation receiv'd from the Russian Emperors Physician already often mention'd by whom I have been assured that about Musco where the surface of the ground is far more constipated in Winter this 't is in these parts and where they are wont to keep their Cellars much closer the subterraneous Exhalations being hinder'd to fly abroad will in time multiply so fast that he assures me that upon the unwary opening of the doors of Cellars that have been long kept shut there would sally out a warm smoak and very thick almost like that of a furnace and sometimes the steam that issues out will be so gross and plentiful that it has brought men into danger of being suffocated by it 51. And now Gentlemen having shown that though Experience be so confidently appeal'd to by the maintainers of Antiperistasis yet she has not hitherto afforded them any thing that much favours their Cause it remains that I show that she bears witness against it For besides that some passages of my late Discourses do really contain Phaenomena that not only do not favour Antiperistasis but may justly be imploy'd as Experiments against it I shall ex abundanti as they speak present you with something which I necessitated Experience to supply me with that seems expresly to overthrow it 52. I might urge against those who though they begin to be asham'd of the Doctrine of the Schools would establish an Antiperistasis upon the account of what they call a fuga Contrarii that the very instance they are wont to bring for their opinion may be retorted upon them For when they tell us that in Winter the heat to fly the cold of the external Air retires it self into the lower parts of the Earth and there harbours in Cellars and Wells as may be prov'd by the smoaking of water drawn from deep Wells which argues its heat the vapours which fly away being as vapours hot in comparison of the outward Air we may easily answer by demanding why if the heat that was harbour'd in a smoaking Bucket of water have the wit or instinct to fly from its Contrary it does not in the Bucket as 't is said to do in the Well retire it self as far as it can from the surrounding cold of the ambient Air but instead of retiring to the innermost parts of the water those being remotest from that it needlesly flies abroad with the vapours it excites and does as it were of its own accord cast it self into the arms of the enemies it should shun And indeed what I just now mention'd to you as related to me by the great Duke of Muscovies Physician does sufficiently manifest that the cause why the Corpuscles that keep Cellars warm abide beneath the surface of the Earth in Winter is not that they fly the cold as their enemy but that they are pent up beneath the ground since when vent is given them they immediately rush into the open Air without fearing the cold even of Russia in the very midst of Winter 53. But I shall press this no further but rather add that the doctrine of Antiperistasis is as little beholding to the following Experiment which I sometimes tri'd in order to the disabusing some Abetters of Themistius I took then an Iron-rod of about the bigness of a mans finger having at one end of it a very broad and thick piece of Iron shap'd almost like a spattule that the quantity of the matter might upon the ignition of the Iron make the heat very considerable then having caus'd this thick end to be made red hot in the fire and having suddenly quench'd it in cold water I could not perceive that the other end of the rod by which it was wont to be held did at all grow sensibly hot as a favourer of Antiperistasis would have expected it should do to a very high degree as presuming that the innumerable particles of heat that swarmed in the compact body of the red hot part of the Iron must to fly the cold of the water retire in throngs towards the other extreme of the Iron and make it exceedingly hot And least any preexistent warmth should hinder me from perceiving an increase of heat in case any were produc'd in the handle of the Iron I caus'd it the next time the Trial was made to be kept in cold water and yet even then the immersion of the broad and candent end into the cold water brought as little of sensible heat to the other end that I held in my hand as it had done the time before and having caus'd the Experiment to be tri'd by another the account I receiv'd was that it succeeded with him as it had done with me 54. But this is not the main thing Gentlemen that I intended to acquaint you with there being an Expedient that I purposely devised to make one Experiment more considerable against Antiperistasis then are the several mistaken observations of the Peripetaticks to establish it 55. I took then a good seal'd Weather-glass 12. or
14. inches long furnished with good spirit of Wine and having provided an open mouth'd glass of a convenient shape and size and fill'd it but to a due height that it might not afterwards run over with common water I so ordered the matter that the stem of the Thermoscope being supported by the cork into which by a perforation or slit it was inserted when the glass was stopp'd by the cork the whole ball of the Thermometer was immers'd in the water that fill'd the wide mouth'd glass and did no where touch either the bottom or the sides of the glass so that the ball or bubble was every way surrounded with water The instrument being thus prepar'd we observ'd at what station the ambient cold water had made the tincted spirit rest in the stem of the Thermoscope and then having provided a fit proportion of warm water in a commodiously shaped vessel I remov'd the instrument into it and plac'd it so as that the external warm water reach'd to a convenient height on the outside of the open mouth'd glass But though I carefully watch'd whether the heat of the external water would increase or strike inwards the cold of that water which did immediately incompass the ball of the Weather-glass yet I perceived no such matter the tincted spirit in the stem keeping its station without sinking beneath it till the heat after a while having by degrees been diffus'd through the formerly cold water by the intervention of that now warmed the tincted spirit in the Thermometer began to ascend 56. And to reduce the other part too of the doctrine of Antiperistasis to the determination of an Experiment the same Thermoscope was plac'd in the same wide mouth'd glass just after the former manner only instead of the cold water that which immediately surrounded the glass was warm and when the warmth had impell'd up the tincted spirit till its ascent began to be very slow I immers'd the instrument to a convenient depth in a vessel that contain'd highly refrigerated water mingled with divers pieces of ice But notwitstanding my watchfulness it did not appear to me that the warmth of the water that did immediately encompass the ball of the Weather-glass was at all increas'd or intended by that Liquors being besieg'd by water exceeding cold for the languid motion of the tincted spirit upwards was not hereby so much as sensibly accelerated as it must have been considerably if the heat of the internal water had been so augmented or struck inwards by the cold of the external as the Schools Doctrine would have made one expect but rather the ascent was by the chillingness of the contiguous water quickly check'd and the formerly ascending spirit was soon brought to subside again And to give my self the fuller satisfaction about some of the chief Phaenomena of this and the former Experiment I had the curiosity to observe them more then once POSTSCRIPT A Sceptical Consideration of the Heat of Cellars in Winter and their Coldness in Summer THe foregoing Discourses of Carneades seem to have sufficiently shaken the Foundations of the Vulgar Doctrine of Antiperistasis so far forth as 't is superstructed upon the Vulgar Observations and Phaenomena whereon men are wont to build it and it seems to have also made it highly Probable that in case some of the Examples wont to be produc'd in favour of Antiperistasis should prove Historically true yet those Phaenomena may more congruously to the wonted proceedings of Nature be explicated by the detention of calorifick or frigorifick Corpuscles by the operation of the external cold or heat then to a cerain inexplicable self invigoration which is commonly propos'd in such a way as invests inanimate bodies with the prerogatives of free Agents But though Carneades his Adversaries seem not to have well made out the Historical part of the receiv'd Doctrine concerning cold yet upon an impartial survey of what has been alledg'd on both sides I freely confess that to me some of the matters of fact themselves seem not yet so clearly determined as I could wish for as to the obvious Phaenomena that nature does as it were of Her own accord present us they seem to have been but perfunctorily considered and our senses only being the judges of them we may easily as Carneades argues be impos'd upon by the unheeded predispositions of our Organs And as for contriv'd and Artificial Experiments there scarce seem to have been any made fit to clear the difficulties that invite me to suspend my judgement as to the grand Question of fact whether Cellars and other subterraneous places be really hotter in Winter then in Summer 'T is true that I have scarce met with any point wherein the modern Schoolmen seem to have so much consulted Nature as in this of Antiperistasis For inquiring what has been written of that subject that may either confirm or oppose what has in the precedent Dialogue been deliver'd about Antiperistasis I found that the curiousness and importance of the subject have made two or three of those writers less negligent then I suspected But though I have lately met with in them an Experiment or two that seem cogently to evince I do not say an Antiperistasis in the sense of the Schools but that subterraneal places are really hotter in Winter then in Summer yet I must for a while longer continue my suspension of judgement which that even such persons as are circumspect themselves may not think unreasonable I will briefly subjoyn the grounds of my Scepticism about this matter First then the learned Jesuite Zucchius who is wont to be far more industrious then other Aristotelians and on some subjects is careful to propose Experiments though he be not so clear and happy in expressing his thoughts assures us somewhere that having kept a good seal'd Weather-glass for three years together in a good Cellar he found the water to rise by the Coldness of the ambient Air in the Summer and to be depressed by the rarefaction of it in the winter which seems undeniably to infer that whatever be the reason of it the heat in subterraneal places is indeed greater in Winter then in Summer And another recent Schoolman who as I am told is of the same order though the learned Man publish'd his little Book under one of his Disciples Names affirms that he found by a Weather-glass that a Well at the place where he lived was colder in Summer and hotter in Winter And these assertions of Zucchius and the other Jesuite do I confess restrain me for a while from yielding a full assent to what Carneades hath delivered as to the matter of subterraneal Cold and Heat But on the other side I am not hitherto reduc'd by these Experiments to declare with his Adversaries against him because of the following scruples First then I consider that 't is not universally true which is wont to be indefinitely affirm'd and believ'd that Cellars and other subterraneal places are hotter in Winter
there is no probability that the ice should be generated according to the way propos'd by Mr. Hobs. For he will scarce prove nor is there any likelihood that a wind pierc'd the shell and closer coats of the Egg to get into the contain'd liquors and freez them and a more unlikely assertion it would be to pretend as he that maintains Mr. Hobs's doctrine must that so very little Air if there be any as is mingled with the juices of the Egg is by the Cold which is not wont to expand Air nor water till it be ready to make it freez turn'd into a wind subtile enough freely to penetrate the shell and coats of the Egg and great enough to diffuse it self every way and turn on every side the neighbouring water into ice and all this notwithstanding that not only it appear'd not by bubbles breaking through the water that there is any Adventitious Air that comes out of the Egg at all but that also supposing there were some such contain'd in the Egg yet what shadow of reason is there to conceive that the Air which was engag'd in and surrounded with the substances of the white and the yelk of the Egg must needs be a wind since according to Mr. Hobs that requires a considerable motion of most of the parts of the mov'd Air the same way and according to him also a body cannot be put into motion but by another body contiguous and mov'd 16. Sixtly Mr. Hobs does indeed affirm that all wind cools but is so far from proving that the highest degrees of Cold must needs proceed from wind that he does not well evince that all winds refrigerate Nor are we bound to believe it without proof since wind being according to him but Air mov'd in a considerable quantity either in a direct or undulating motion it does not appear how Motion should rather then Rest make Air grow cold For though it be true that usually winds seem Cold to us yet in the first place it is not universally true since some that have travelled into hot Countries and particularly the learned Alpinus have complain'd that the winds coming to them in the Summer from more torrid Regions have appear'd to them almost like the steam that comes out at the open mouth of a heated Oven And if Marcus Polus Venetus be to be credited for I mention his Testimony but ex abundanti the Southern winds near Ormus have been sometimes so hot as to destroy an Army it self at once And secondly even when the wind does feel cold to us it may oftentimes do so but by accident for as we elsewhere likewise teach the steams that issue out of our bodies being usually warmer then the ambient Air whence in great Assemblies even those that are not throng'd find it exceeding hot and I have several times observ'd a hot wind to come from those throngs and beat upon my face and the more inward parts of our bodies themselves being very much hotter then the ambient Air especially that which is not yet full of warm steams the same causes that turn the Air into a wind put it into a motion that both displaces the more neighbouring and more heated Air and also makes it pierce far deeper into the pores of the skin whereby coming to be sensible to those parts that are somewhat more inward then the Cuticula and far more hot the Air turn'd into wind seems to us more cold then the restagnant Air if I may so speak upon such another account as that upon which if a man has one of his hands hot and another not the same body that will appear luke-warm to this will appear cold to the other because though the felt body be the same yet the Organs of feeling are differingly dispos'd And to confirm this doctrine by an Experiment which has succeeded Often enough and need not succeed Always to serve our present purpose we will add that though Air blown through a pair of Bellows upon ones hand when 't is in a moderate temper will seem very cold yet that the ambient Air by being thus turn'd into wind does indeed acquire a relative coldness so as to seem cold to our senses but yet without acquiring such a cold as is presum'd may appear by this that by blowing the same air with the same Bellows upon Weather-glasses though made more then ordinarily long and by an Artist eminent at making them we could not observe that this winds beating upon them did sensibly refrigerate either the Air or the liquor Though 't is not impossible but that in some cases the wind may cool even inanimate bodies by driving away a parcel of ambient air impregnated with exhalations less cold then the air that composes the wind But this is not much if at all more then would be effected if without a wind some other body should precipitate out of the air near the Weather-glass the warmer Effluvia we have been mentioning especially if the Precipitating Body introduce in the room of the displaced Particles such as may in a safe sense be term'd Frigorifick 17. Seventhly Nor can we admit without a favourable construction Mr. Hobs his way of expressing himself where he says as we have lately seen that All wind cools or deminishes former heat For if we take heat in the most common sense wherein the word is used not only by other writers but also by Philosophers to make wind the adequate cause of cold it must in many cases do more then diminish former heat For water for instance that is ready to freez is already actually cold in a high degree and yet the wind if Mr. Hobs will needs have that to be the efficient of freezing must make this not hot but already very cold liquor more cold yet before it can quite turn it into ice 18. These things thus establisht it will not be difficult to dispatch the remaining part of Mr. Hobs his Theory of Cold for to proceed to his sixth Section we shall pass by what a Cosmographer would perhaps except against in his doctrine about the generation and motion of the wind upon the surface of the Earth and shall only take notice in the remaining part of that Section of thus much That the most of what Mr. Hobs here shews us is but that there is an expansion of the air or a wind generated by the motion and action of the Sun but why this wind thus generated must produce cold I do not see that he shews nor does his affirming that it moves towards the Poles help the matter for besides that we have shewn that wind as such is not sufficient to produce far less degrees of cold then those that are felt in many Northern Regions there must be some other cause then the motion of the air or steams driven away by the Sun to make bodies not in themselves cold for so they were suppos'd not to be when the Sun began to put them
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
glass been broken I exposed another lesser Tube with the same oyl which became frozen throughout and required very much relaxation in the air to return to its former fluidity I had set a mark on these Tubes as on all the rest to observe their several risings and the oyl of Vitriol when coagulated sunk more then half an inch below it and being dissolved at the fire returned to its first station as you also saw And this 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 is peculiar to this oyl alone all other liquors rising higher then the mark I now come to my stronger liquors of Beer Ale and Wines I exposed at the same time a flask of small Beer and another of strong Ale the former whereof was frozen throughout in 38. hours but three pints of the Ale continued unfrozen after six days continuance of very hard weather And the air then disposed to thawing I broke the flask and with the unfrozen liquor made an excellent mornings draught at four in the morning This Ale in colour strength and quickness seemed to me and the other three tasters that sate up with me much better then when 't was first put into the flask and by comparing it with some other in the house of the same barrel we plainly found the said difference After this I took the icy part of the Ale and thawed it at a fire which was in all a pint of liquor though the flagon containing three pints of liquor was fill'd with that ice very pale and of a quick and alish taste very much resembling that drink which the brewers call blew John This ice was not so firm as that of water but fuller of bubbles I assayed the same a second time but could not by reason of the changableness of the Weather attain so great a thickness of ice as in the former And in this also I found the same changes as before A beer-glass of Hull Ale in 24. hours contracted a crust of ice as thick as an ½ Crown and proceeding as in Sea-salt water the 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 were the very same all the Laminae taken off appeared of the same colour and taste and the lowest ice was the most tender Another glass of the same Ale exposed did not freez throughout no crust being taken off in five days when my own Ale did in a like glass both being set out together Now the taste and colour appeared the same or at least had no sensible difference when they had been thawed of themselves and when first exposed Hull Ale hath a brackish taste Claret very strong exposed in a spoon in 35. hours hard freezing became an ice all of it it was soft kept its former colour and taste soon discovering to the tongue of one who knew not whence it was its nature quality and kind Canary at the same time in a spoon exposed in 38. hours acquired on its surface an exceeding thin plate of ice as thin as the finest paper and proceeded no farther in four days following Neither Claret nor Canary would shew the least sign of congelation in Tubes much less in Bottles Two ounces of the best spirit of Wine exposed in an earthen pan did all evaporate in less then 12. hours but the same quantity of Brandee left near a spoonful of insipid ice without any taste of the spirit which cast into the fire flamed not at all I could discern no bubbles in this phlegmatick ice but having 〈◊〉 it betwixt mine eye and a candle it manifested many bubbles by its shadows Quaere whether this may not turn to profit in colder Countries in rectifying spirits of Wine We now come to consistent bodies and shall begin with animals and their parts Two eyes the one of an Ox the other of a Sheep in one night were both totally frozen the three humors very hard not separable one from another neither of them Diaphanous as naturally they are and the Chrystalline was as white as that of a whitings boil'd The Tunicles Fat and Muscles were also frozen as appeared by their stifness and by putting them into cold water The ice of the waterish and glassy humors seemed to be made of flakes A pint of Sheeps blood did freez at the top and all the sides of the dish wherein 't was put and was nothing else but the serum of the blood This ice being separated from the blood and thaw'd at the fire and then again exposed congealed into a seeming membranous substance and was taken for such by some that saw it and so continued in a warm season and appeared in all respects a membrane This also was seen and registred in the Journal The blood remaining gave me no signs that frost had taken it I dissected a Dog and a Cat having lain dead in the open air and found their entrails nay the very heart stiff and some little ice in the Ventricles of their hearts and their Vena Cava Milk soon freezeth into most white flakes of ice retaining the proper taste of Milk these flakes are soft and manifest not many bubbles Several Eggs were exposed and both yolk and white in one night were hard frozen They require a longer time to freez then Apples do The best way to thaw them both is to lay them on Newcastle-coal or in a deep Cellar Whether Eggs once frozen will produce Chicken or no I cannot say but have been told by good house-wives they will Some affirm that Eggs and Apples put into water the ice will be thawed within them and the ice appear on the shell and skin 'T is true if you hold either of them near the surface of the water they will soon gather a very thick crust upon their outsides but if you then break the one or cut the other you shall see them full of ice and the Eggs then poched will taste very tough So that this ice seems to be gathered from without and not to come from within And besides if it did so they must needs lose their weight the contrary whereof will anon appear But for the more surety I proceeded to this farther experiment I immersed in my Cistern an Egg and an Apple two foot deep into water and there suspended them with strings tied about them to keep them from sinking for the space of 24. hours and then took them out and opened them I could never observe in that time though I often looked at them any ice on their outsides and the one being broken and the other cut were found both of them full within of ice The next order shall be Vegetables and of them a 〈◊〉 instances 〈◊〉 of those which are of a biting or sowre taste Now for the first I employed the roots of horse-raddish and Onions for other edible roots and plants every one knows will freez which 〈◊〉 the frost had taken them by their taste and ice was found betwixt each of the skins of the Onions 〈◊〉 the taste of the root yet I have observed Beer wherein
Horse-raddish and 〈◊〉 have been infused will not 〈◊〉 so soon as other stronger Beer without them Oranges and Limons frozen have a tough and hard rind their icy juices lose much of their genuine taste they were both frozen hard in 26. hours or a little more having a thick rinde They as other fruits when thawed soon become rotten and therefore the Fruiterers keeps them under ground in low Cellars and cover them with straw as they do their Apples Which did exposed in one night freez throughout If you cut one of them through the middle 't will have on both the plains a most pure thin ice hardly discernable by the eye but easily by the touch or by scraping it off with a knife The cores of these Apples soon turn brown and begin their corruption there Oyl exposed did acquire the consistency of butter melted and cool'd again but in Caves and Cellars I could never see it more then candy Strong White-wine Vinegre did all soon freez in a Tube and without any apparent bubbles And to conclude without mentioning Nuts Bread Butter Cheese Soap and many other things which came under my trial 't is most certain that whatsoever hath any waterish humidity in it is capable of congelation what are not you have in the next Paragraph Having now done with what will freez I shall briefly recount some things whereon the cold hath no such effect We mentioned before spirit of Wine add to it such strong waters as are made of it viz. Aqua Mariae Caelestis c. and Canary Wines in larger vessels Secondly the strong Lees of Soap-boylers and others made of other salts to which refer the spirits extracted from salt Vitriol Salt Petre Aquafortis and spirit of Sulphur which last precipitated to the bottom of the Tube a small quantity of powder very like in colour to Sulphur Vivum which being separated from the spirit for nothing of that evaporated cracked between my teeth and tasted like Brimstone and being put into water made it as white as Lac Sulphuris doth but 't would not flame perhaps because too much of its strong acid spirit was mixed with it Spirit of Soot afforded also a precipitation or sediment the spirit not congealing at the bottom of the Tube of a yellowish colour but much bitterer then the spirit its self and inflamable also But here 't is to be observed that the said spirits that would not freez alone yet with the mixture of about 12. parts of water or less of ice or snow did freez throughout except the spirits of Salt of Nitre and Aqua fortis which would not freez with those quantities of water ice and snow I intended to have tried them with a greater quantity of the said ingredients but the weather failed me Whether the salt water freez in the Sea I cannot experimentally determine but shall add what was told me by one that said he had dissolved ice in the Northern Seas and found it very salt The next proposed was the figure of liquors frozen wherein I shall observe in general that most of the liquors differed one from another in their figures and being permitted to freez and thaw often they still returned to the same figure most whereof were branched Alume appeared in lumps Salt Petre Tartar milk Ale Wine and Sal Armoniac in plates and other liquors mentioned to freez into a very soft ice seeming to be made up of small globuli adhering each to other Fair water kelp and the frits resembled an oaken leaf the leafie parts being taken away and the fibres only remaining the interstitia being fill'd up with smoother ice The middle rib if I may so say as in plants was much bigger then the lateral ones all which seemed but different 〈◊〉 whose points extended towards the outside of the vessel containing the water and made acute angles with the middle rib towards the lesser end of the said leaf Concerning the figures of frozen Urine I shall say nothing the accurate description of curious Mr. Hook having so fully and truly performed that part of my task Now as to the famous experiment of Quercetan and affirmed by many other Chymists I made experiments in these following Vegetables Rosemary Rue Scurvigrass Mints and Plantane wherewith I thus proceeded I mixed with ½ a pint of their distilled waters ½ or ¾ of an ounce of their own salts the Rosemary and Rue were calcined and their salts extracted with their own waters and then were added to their salts their own distill'd waters in the above mentioned proportions The glasses wherein the Rue and Plantane were put being seal'd with Hermes seal and the other glasses left open The effect was that neither of them shewed the least resemblance of the plants from which they were extracted neither figure nor shew of roots stalks branches nor leaves but only a lump or heap of small globuli much less of flour or seed Besides the kelp frozen hath many fibres which is made the most of it of Alga Marina whose leaf is long and smooth without fibres in it This one thing I cannot pretermit that the sented waters seemed upon their thawing to have acquired and advanced much in their sents and especially the Rosemary whose salt hath no smell and its water but little yet thawed they 〈◊〉 as strong almost as fresh leaves rubb'd and smelt too A large recipient was fill'd with water which being frozen throughout and the upper crust of the ice broken there appeared in the middle of it a multitude of thin laminae of ice some more some less wide from which proceeded stiriae or teeth pointing inwards and set at pretty equal distances so that the laminae and stiriae resembled very much so many combs placed in no order some lying directly others obliquely none transversly having intervals betwixt each of them betwixt some of them I could put my finger without breaking the points of the stiriae these combs were placed round about a cavity in the middle of the receiver sufficient to receive two of my fingers In a flask filled competently with water when 't was frozen there appeared throughout the ice infinite silver-coloured bubbles very like unto tailed hail-shot of several sizes the largest about ¼ of an inch long where thickest of the bigness of a great pins-head others much less in all dimensions The points of them all looked outwards and the bigger part inwards towards the Centre where also were the largest For there they would easily admit a little pin into all their cavity without the least resistence The figures of them were pretty regular first a small thread and then a head as big as a shot and thence gradually ended in a point Some of these were straight most a little crooked There was a cavity in the centre of this ice filled with unfrozen water from which I could find multitudes of cavities of bubbles not fully formed And in the more solid parts of the ice cut you may discern them
a far deeper colour and bitterer taste in the middle and towards the bottom then towards the outsides of it And whereas Barclay relates that King James being in Denmark to fetch his Queen thence in the Winter season had his nose and ears in danger of Gangreening which being timely perceived by some of the King of Denmarks Nobility they caused the parts to be rubbed with snow and so the danger was avoided the same travellers affirm that in the Northern parts where men become stiff with cold and almost frozen to death that they rub the frozen parts with snow or else cast the whole body into water by which means the whole body is crusted over with ice as Eggs and Apples are as if the freezing Atoms did pass from the body frozen into the water or snow and this way of curing Gangreens from cold Sennertus doth prescribe To make some Experiment hereof I exposed flesh and fish and found that by immersing them into water they soon became more limber and flexible and more easily yielding to the knife and compassed with a crust of ice of the thickness of about half a crown manifest tokens of their thawing and being cut they discovered nothing of ice in them This for more certainty I often reiterated as also in Eggs and Apples above a dozen times and never failed of unthawing them by this way 'T is to be noted if you immerse the flesh fish eggs or apples deep into the water no ice will appear on their outsides but only when you hold them neer the surface of the water As to the Persian Experiment mentioned by Olearius of making huge heaps of ice to be preserved for cooling of their drinks I observed that by pouring water into an open Pan or into a Flask gradually some at one time some at another I could quickly freez by this way a whole Flaskfull when near half of a Flask filled at one though helped by art was unfrozen I observed also that the ditches betwixt Southwark and Redderiff had acquired an exceeding thickness of ice caused by the flowing of the water in them at full Tide for new water being brought in by the Tide was there congeal'd to the thickness of some inches every ebbing and flowing I observed also the ice on the banks of Thames above two yards thick the inhabitants told me they had seen it three or four yards thick which thus came to pass the Tide flowing in and meeting with great flakes of ice drove them to the banks and lodged them on the ice there frozen which flakes uniting there with the former ice raised it to that excessive height or thickness Besides every one may observe in London Streets and elsewhere in Chanels where no constant current is that water coming from the houses soon fill the Chanels with thick ice for running but a little at a time it freezeth almost as fast as it cometh thither Nay I have seen ice of some yards thickness in such places where a small rill or stream of water gently falls on the side of a hill Amongst those things that will freez Mortar and Plaister of Paris were omitted and thence 't is that Plaisterers and Bricklayers play all the Winter My Lord Verulam in his natural History and some from him have affirmed to me that Apples and Eggs covered with a wet cloath will not freez but I find no difference in those that are thus covered and them that are not Add to those that sink upon congelation all oyls from Animals and from Vegetables that are extracted by expression or boiling Add to those that freez not water and Sugar boiled to the consistence of a Syrup and also all other Syrups none whereof I could ever take notice or learn by others that they would freez 'T is true that water having an equal quantity of Sugar dissolved in it will freez but with a little more mixed therewith freezeth not To try the effect of cold upon Loadstones I exposed several of them in the open Air and also within rooms in the most severe weather the needle being kept in a warm place At other times I exposed the needle to the cold air keeping the stones warm at other times both were exposed but in none of my Experiments could I conclude any thing certain to their attractive faculty for the sphere of their activity was found to be sometimes greater and sometimes less to a considerable difference in ten several good stones imployed for this purpose I essayed also to find out a standard of cold whereby to fit the tinged spirit of Wine for the Weather-glasses and to that end made use of Conduit water and the distilled waters of Plantane Poppies Black-Cherry Nightshade Scurvigrass and Horse-raddish all which were first placed in the same room where a fire was kept and then removed and measured out into spoons in equal quantities and also a drop of them dropt on the same bench but though this was often tried I could not make any sure inference from them only I observed that the black-Cherry water did for the most part freez first but the other with very great uncertainty The Horse-raddish and Scurvigrass waters were for the most part froze last The best way to discover the very beginning of freezing of liquors is to move a Pin or Needle through the liquors whereby the ice will be raised and become discernable when the naked eye can discover none at all FINIS Figure 1. Page 9 10 11 â— 98. A the Ball or Egg. B C the Stem D the little Aqueous Cylinder Figure 2. the open Weather glass mentioned pag. 24 43 Figure 3. the seal'd Weather-glass or Thermoscopâ—mentioned pag. 24 55 56. Figure 4. the Barometer oâ— Mercurial Standard placed in Frame B B mentioned pag. 25 Figure 5. an Instrumenâ— mentioned pag. 93. A the Vial. B C the Pipe cemented in t the neck of the Vial open at â— and seal'd at B. Figure 6. pag. 97. A the Bolt-head B the small Stem B C the Cylinder of wateâ— inclos'd Figure 7. pag. 101. * It was thought needless to insert Mr. Hobs's Scheme touching this subject because it only shews that Wind is the cause of Cold. Sceptical Chymist * Chapter the fifth of that Treatise * The two Essays of the Unsuccesfulness of Experiments * Another remarkable instance of the variable success of the Experiments of Cold I 〈◊〉 〈◊〉 with in an Experiment 〈◊〉 the 〈◊〉 Dr. 〈◊〉 〈◊〉 the 〈◊〉 of oyl of 〈◊〉 For though I 〈◊〉 that Liquor in smal ' vessels of 〈◊〉 〈◊〉 and 〈◊〉 and 〈◊〉 in 〈◊〉 〈◊〉 〈◊〉 〈◊〉 at one 〈◊〉 〈◊〉 〈◊〉 the 〈◊〉 of the Air in 〈◊〉 nights 〈◊〉 extraordinarily sharp 〈◊〉 〈◊〉 is more our 〈◊〉 〈◊〉 〈◊〉 〈◊〉 and Salt would 〈◊〉 the Experiment succeed 〈◊〉 that we tri'd it with several parcels of Oyl of Vitriol And yet that the Learned Doctor by the help of the Air alone for he uses not our 〈◊〉 mixture did bring that Liquor either to
but the interspersion of such bubbles The Observations I have been mentioning I find thus set down among my Notes A piece of Ice that to the Eye look'd clear like crystal being put into the great Microscope appear'd even there free from bubbles and yet the same piece of Ice being presently remov'd and cast into common water would swim at the top and if it were forcibly duck'd would swiftly enough emerge Another piece of Ice that to the naked Eye was not so clear as the former appear'd in the same Microscope to have store of bubbles some of them appearing there no bigger then a small pins head and some of them being yet lesser and scarcely visible in the Microscope it self And here because it seems a considerable doubt and well worth the examining whether or no water when frozen into Ice grows heavier or lighter not in reference to such water as it was generated of since it is evident that upon that it will float but more absolutely speaking we judg'd it not amiss to examine this matter by an Experiment but we could not discover any difference between the weight of the same parcel of water fluid and frozen as will appear by the ninth Paragraph of the Experiment to be a little beneath recited But since that whether or no we allow any other cause together with the bubbles to the levity of Ice it seems a thing not to be doubted that its expansion and lightness is mainly if not only due to the interspersion of bubbles the generation of them seems to be one of the considerablest Phaenomena of Cold and the Investigating by what cause those cavities are produced and in case they be perfectly full what substance 't is that fills them is none of the meanest enquiries that should exercise the industry of a searcher into the Nature of Cold. 4. Mr. Hobs and some others seem to think that the expansion of water by congelation is caus'd by the Intrusion of Air which constitutes those numerous bubbles wont to be observ'd in Ice we might here demand why in case that upon freezing there must be a considerable accession of Air from without when oyl is frozen it is notwithstanding the ingress of this Air not expanded but condens'd but because these conjecturers do not allow glass to be pervious to common Air we shall at present press them with this Experiment which we have divers times made We took a glass-Egg with a long stem and filling it almost with water we seal'd it Hermetically up to exclude the pretence that some adventitious Air might get in and insinuate it self into the water and yet such an Egg being exposed to congelation the frozen water would be manifestly expanded and swell'd by numerous bubbles which oftentimes gave it a whitish opacity To which we may add that new metalline vessels being fill'd with water and carefully stopp'd the liquor would nevertheless when exposed to the Cold be thereby expanded and turned into Ice furnished with bubbles 5. If it be objected that in the Experiment of the Hermetically seal'd glass the produced bubbles might come from the Air which being seal'd up together with the water might by the expansion of that water be brought to mingle with it I answer that this is very improbable For 1. if the bubbles must cause the expansion of the water how shall the water be at first expanded to reduce the Air to a Division into bubbles Next 't is evident by the Experiments we shall ere long relate that the Air as to the Body of it retains its station above the water and preserves it self together in one parcel since it suffers a compression that oftentimes makes it break the glass that imprisons 〈◊〉 which it would not need to do in case it dispers'd it self into the Body of the water for then there would appear no cause why the Air and water should after congelation require more room then they did before 3. In this Experiment we usually begin to produce Ice and bubbles in the water contiguous to the bottom of the vessel that part being by the snow and salt first refrigerated in which case there appears no reason why the Air which is a thousand times lighter then the water should against its nature dive to the bottom of the water and if it were disposed to dive why should we not see it break through the water in bubbles as is usual in other cases where Air penetrates water 4. In metalline vessels and in Glasses quite filled with water before they are stopped there is no pretence of the diving of the Air from the top there having been none left there 5. and lastly If all the bubbles of Ice were made by and filled with true Air descending from the upper parts of the vessels and only dispersed through the water then upon the thawing of this Ice the Air would emerge and we might recover as much of real Air as would fill the space acquired by the water upon the account of its being turned into Ice which is contrary to our Experience And this Argument may also be urged against any that should pretend for I exspect not to see him prove it that though Air as numerous experiments evince cannot get out of a seal'd glass yet it may in such a case as this get into it But we find upon trials that the Cavities of these bubbles are not any thing near filled with Air if they have in them any more Air at all then that little which is wont as we have elsewhere shewn to lurk in the particles of water and other liquors And the making good of this leads us to the second Enquiry we were proposing about these bubbles namely whether or no their cavities be fill'd and fill'd with Air. 6. The full resolution of this whole Difficulty would be no easie Matter nor well to be dispatched with so much brevity as my occasions exact For it would require satisfactory Answers to more then one or two Questions since for ought I know it may lead us to the debate of those two grand Queries whether or no Nature admit a Vacuum and whether a great part of the Universe consist of a certain Ethereal matter subtile enough to pass through the pores not only of liquors but of compact bodies and even of glass it self we should also be obliged to enquire whether or no Air I mean true and permanent Air can be generated anew as well out of common water as many other liquors and whether it may be generated by Cold it self and perhaps we should be oblig'd to inquire into the Modus of this production and engage our selves in divers other difficulties whose full Prosecution besides that they would as much exceed our present leisure as Abilities seems more properly to belong to the more general part of Physicks where such kind of general Questions are fittest to be handled Wherefore we will now only consider this Particular Question whether or no the Cavities of