particular Bodies and the differing degrees of Cold and the differing times wherein the Condition of the expos'd Body is estimated be taken into Consideration For we find that a moderate degree of Cold preserves many Bodies and that glaciation destroys or at least prejudices most others probably by discomposing or vitiating their Texture when they come to be thaw'd though whilest the Frost is in them it keep almost all Bodies from disclosing any putrefaction 17. This being the general Consideration I intended to propose it remains that I add out of credible Writers or other Relators some Observations to illustrate and confirm the chief particulars comprehended in it And first that a moderate degree of cold conduces much to the preservation of the greatest part of inanimate Bodies is a thing vulgarly taken notice of and acknowledg'd And I do not readily remember any instances that manifest that any degree of Cold though more then moderate provided it fall short of freezing the Bodies expos'd to it does spoil them Regii Mutinenses says the industrious Bartholinus nivem hoc fine arctè 〈◊〉 servant in Cellis Nivariis in quibus fervente aestate vidi carnes mactatorum Animalium à putredine diu se conservasse The next thing I shall mention to our present purpose is a memorable passage in Captain James's Voyage which shows that so great a Degree of Cold as may be suppos'd to have reign'd in his ship that was frozen up all the Winter in one of the Coldest Regions of the World was not great enough to spoil the meat and drink that had layen all that time under water because it seems by the story that they were not actually frozen the words of his Journal are these By the Ninth of May we were come to and got up our five Barrels of Beef and Pork and had four Buts of Beer and one of Cyder which God had preserved for us it had layen under water all the winter yet we could not perceive that it was any thing the worse which is the more remarkable because of what we shall note by and by both out of other Books and even out of this about what became of a stronger Liquor then Beer once brought to Glaciation And it seems our Navigator found Cold if extremely intended so destructive a thing that he thought fit to take notice in his Journal That even a Cable having layen under the ice all the Winter was not in June found a jote the worse 18. And it seems by a passage in Simlerus's account of the Alpes that even Intire Bodies may be very long preserved by snow and as far as I can guess by the story without glaciation Refert says Bartholinus speaking of him in Rhetis apud Rinwaldios nivium è monte ruentium 〈◊〉 sylvam 〈◊〉 Abietes dejecisse accidisse etiam Helvetio milite per Alpes iter faciente ut 60. homines plures eadem nivis conglobatione opprimerentur Hoc igitur Nivium tumulo sepulti ad 〈◊〉 Aestatis delitescunt quo solut â nonnihil Nive Deciduâ Corpora mortua inviolata patent si ab amicis vel transeuntibus quaerantur Vidimus ipsi triste hoc spectaculum c. 19. Secondly I could alledge many instances to show that many if not most inanimate Bodies I say inanimate because of the Gangraenes and Sphacelations that often rob living men of frozen Toes Noses and sometimes other parts if they be actually frozen will not disclose any putrefaction whilest they continue in that state Nor is this much to be wondred at since whether we will suppose that in Glaciation the moist and fluid parts are wedg'd in by intruding swarms of frigorifick Atomes or that those restless particles that were wont to keep the Body fluid or soft are called forth of it be the cause of glaciation which soever of these two ways we pitch upon we must in frozen Bodies conceive an unwonted rest to be produced of those movable particles whose internal commotions and disorderly coalitions and Avolations are either the Causes or the necessary Concomitants of Corruption 20. On this Occasion I remember that meeting with a knowing Man whose affairs stopp'd him during the Winter upon the Coasts of Sweden and Denmark being desirous to learn of him how long they could in those colder Climates preserve in Winter Dead Bodies unburied and yet uncorrupted he told me he had opportunity to observe that though the frost lasted as it usually did in that season three or four moneths together or longer the Bodies might without any Embalming or other Artificial way of preservation be kept untainted by the bare coldness of the Air. Of Bodies lasting long unputrified in ice Navigators and others have afforded us several instances but we will mention two because they contain something more remarkable then the rest The one is thus delivered by Bartholinus Notandum Corpor a occisorum hyeme eodem positu eademque figur â permanere rigidâ quâ ante eadem depraehensa sunt Visum id extra urbem nostram quum 11. Feb. 1659. oppugnantes hostes repellerentur magnaque strage occumberent alii enim rigidi iratum vultum ostendebant alii oculos elatos alii ore diducto ringentes alii Brachiis extensis gladium minari alii alio situ prostrati jacebant Imo ex mari gelato primo vere resoluto eques equo suo insidens integer emersit nescio quid manibus tenens The other instance is afforded us by Captain James's Journal and is by him thus delivered In the Evening of the 18. of May the Master of our ship after Burial returned aboard ship and looking about her discovered some part of our Gunner under the Gun-room ports This man we had committed to Sea at a good distance from the ship and in deep water near six moneths before The 19. in the morning I sent Men to dig him out he was fast in the Ice his head downwards and his heel upwards for he had but one Leg and the Plaister was as yet at his wound in the afternoon they digged him clear out after all which time he was as free from noisomness as when we first committed him to Sea This alteration had the Ice and water and time only wrought on him that his flesh would slip up and down upon his 〈◊〉 like a Glove on a mans hand But there is one pertinent particular more which if it be strictly true is so very remarkable that I cannot on this occasion forbear to annex it which is That according to the relation of the Merchants of Copenhagen that return thither from Spitzberg a place in Greenland the extreme Cold will there suffer nothing to putrifie and corrupt insomuch that Buried Bodies are preserved 30. years 〈◊〉 and inviolated by any 〈◊〉 21. Thirdly though whilest Bodies continue frozen the cold as may be supposed by arresting the insensible particles from whose tumultuary motions and disorderly Avolations Corruption is wont to
known in the Hot Countries where he liv'd made those that were bitten by them either become or think themselves very cold But that will perhaps seem more remarkable which I shall further add namely that I know a Nobleman who follow'd the Wars in several Countries and has signaliz'd his Valour in them and yet though his stature be proportionate to his courage yet when this person falls as frequently he has done in a fit of the stone he feels an universal cold over his whole body just like that which begins the fit of an Ague And though he assures me that the stones that torment him and which he usually voids are but very small yet whilest the fit continues which oftentimes lasts many hours he does not only feel an extraordinary Coldness but which is more strange and which I particularly inquir'd after cannot by clothes or almost any other means keep himself warm 10. I elsewhere take notice of some other Observations agreeable to these by some of which we may be perswaded that there may be other ways besides those already mention'd of perceiving cold though the outward parts of our bodies were not prest inwards And whereas Mr. Hobs infers that He who would know the cause of cold must find by what motion or motions the exterior parts of any body indeavour to retire inwards that seems but an inconsiderate direction For in compressions that are made by surrounding bodies there is produc'd an indeavour inward of the parts of the comprest body though no Cold but sometimes rather Heat be thereby generated And I hope Mr. Hobs will not object that in this case the parts do not retire but are thrust inwards since according to him no body at all can be moved but by a body contiguous and mov'd But what I have hitherto taken notice of being chiefly design'd to shew that the notion of cold in general is not so obvious a thing to be rightly pitch'd upon as many think and that therefore it needs be no wonder that it hath notbeen accurately and warily propos'd by Mr. Hobs I shall not any further prosecute that discourse but proceed to what remains Next then the Cause he assigns why a man can blow hot or cold with the same breath is very questionable partly because he supposes in part of the breath such a simple motion as he calls it of the small particles of the same breath as he will not easily Prove and as eminent Astronomers and Mathematicians have Rejected and partly because that without the suspected supposition I could by putting together the Conjectures of two learned Writers and what I have elsewhere added of my own give a more probable account of the Phaenomenon if I had not lome scruples about the matter of Fact it self which last clause I add because though I am not sure that further Trials may not satisfie me That the Wind or Breath that is blown out at the middle of the compress'd Lips has in it such a real coldness as men have generally ascrib'd to it yet hitherto some Trials that my jealousie led me to make incline me to suspect there may be a mistake about this matter and that in estimating the Temper of the produc'd Wind our senses may impose upon us For having taken a very good and tender seal'd Weather-glass and blown upon it through a glass-Pipe of about half a yard long that was chosen slender to be sure that my breath should issue out in a small stream by this wind beating upon the ball of the Weather-glass I could not make the included spirit of Wine subside but manifestly though not much ascend though the Wind that I presently blew through the same Pipe seem'd sensibly cold both to the hand of by-standers and to my own and yet mine was then more then ordinarily cold So that having no great enencouragement to enter into a dispute about the cause of a Phaenomenon whose Historical circnmstances are not yet sufficiently known and cleared I will now proceed to add that whatever be the cause of the effect there are divers things that make Mr. Hobs's Hypothesis of the Cause of Cold unfit to be acquiesc'd in For we see that the grand cause he assigns of cold and its effects is wind which according to him is Air moved in a considerable quantity and that either forwards only or in an undulating motion and he tells us too that when the breath is more strongly blown out of the mouth then is the direct motion prevalent over the simple motion which says he makes us feel cold for says he the direct motion of the breath or air is wind and all wind cools or diminishes former heat To which words in the very next line he subjoyns that not only great but almost any ventilation and stirring of the Air doth refrigerate But against this doctrine I have several things to object 11. For first we see there are very hard frosts not only continued but 〈◊〉 begun when the Air is calm and free from winds and high and boisterous Southerly winds are not here wont to be near so cold as far weaker winds that blow from the North-east 12. Next if Mr. Hobs teach us that 't is the direct motion of the stream of breath that is more strongly blown out that makes us feel Cold he is obliged to render a reason why in an Aeolipile with a long neck the stream that issues out though oftentimes far stronger then that which is wont to be made by compressing the Lips at a pretty distance from the hole it issues out of is not cold but hot 13. Thirdly Mr. Hobs elsewhere teaches that when in our Engine the pump has been long imploy'd to exhaust as we say the Receiver there must be a vehement wind produc'd in that Receiver and yet by one of our other Experiments it appear'd that for all this in a good seal'd Weather-glass plac'd there before the included Air begins to be as we say emptied there appear'd no sign of any intense degree of cold produc'd by this suppos'd wind so that either the wind is but imaginary or else Mr. Hobs ascribes to winds as such an infrigidating efficacy that does not belong to them 14. Fourthly we find by experience that in hard frosts water will freez not only though there be no wind stirring in the ambient Air but though the liquor be kept in a close room where though the wind were high abroad it could not get admittance and some of our Experiments carefully made have assured us that water seal'd up in one glass and that glass kept suspended in another glass carefully stopt to keep out not only all wind but all Adventitious Air may nevertheless be not only much cool'd but turn'd into ice 15. Fifthly we found by other Experiments that a frozen Egg though suspended in and perfectedly surrounded with water where no wind can come at it will be every way crusted over with ice in which case
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
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
outsides are for the most part unknown even to Chymists themselves divers other Bodies besides Salt-petre whose steams may have a power of refrigerating the Air as great in proportion to their Quantity as those of Salt-petre and since common salt in artificial glaciations is found to cooperate as powerfully as Salt-petre it self and since it is undeniably a Body of which there is a vast quantity in the Terrestrial Globe and which by reason of the Sea where it abounds is exceedingly diffus'd I see no great reason why we may not aswel esteem that kind of Salt among the Catholick efficients of Cold and the rather because that the smallest Corpuscles our eye discerns of Sea-salt are wont to be though not exactly of a Cubical figure which is that figure Philoponus informs us the great Democritus of old justly admir'd by Gassendus assign'd to the Atoms of cold whereas according to Gassendus himself the Corpuscles of Nitre at least as far as sense has inform'd us are not the most conveniently shap'd to produce cold since he labours to show that the figure of frigorifick Atoms is to be Tetrahedrical or Pyramidal whereas the Crystals or Grains great or small into which good Salt-petre shoots are wont to be Prismatical having their base Sexangular but to return to what I was saying concerning the congealing of water with ice I shall subjoyn that the same Experiment countenances my conjecturing that oftentimes it may not be emanations of one Salt or other Body but a peculiar and lucky conjunction of those of two or more sorts of them that produces the intense degree of cold as we see that ice and snow themselves have their coldness advanc'd as to its effects by the mixture either of Sea-salt or Nitre or spirit of Wine or any other appropriated additaments Nay I may elsewhere have occasion to shew that actual Cold may be manifestly promoted if not generated by the addition of a Body that is not actually Cold. But to all this I must add that I doubt whether any of those saline or Terrestrial expirations either single or conjoyned be the adequate causes of cold since for ought I know there may be other ways of producing it besides the introduction of frigorifick whether Atoms or Corpuscles of which we may have occasion to take some notice hereafter In the mean time having discours'd thus long against the admitting a primum frigidum I think it not amiss to take notice once more that my design in playing the Sceptick on this subject is not so much to reject other mens probable opinions of a primum frigidum as absolutely false as 't is to give an account why I look upon them as doubtful Title XVIII Experiments and Observations touching the Coldness and Temperature of the Air. 1. I Have shewn in the former Section that the Air is not the Primum Frigidum but yet I cannot readily yield my assent to the Opinion of the learned Gassendus and some others who have written before and since him that the Air is of it self indifferent that is neither cold nor hot but as it happens to be made either the one or the other by external Agents For if we take Cold in the obvious and received Acception of the word that is for a Quality relative to the senses of a Man whose Organs are in a good or middle Temper in reference to Cold and Heat 〈◊〉 am hitherto inclinable to think that we may rather attribute Coldness to the Air then either Heat or a perfect Neutrality as to Heat and Cold. For to make a Body cold as to sense it seems to be sufficient that its minute Corpuscles do less agitate the small parts of our Organs of Feeling then they are wont to be agitated by the Blood and other fluid parts of the Body and consequently if supposing the Air devoid of those calorifick and frigorifick Atoms to which the learned Men I was naming ascribe its heat and cold it would constitute a fluid which either by reason of the minuteness of its parts or their want of a sufficiently vehement motion would less affect the sensory of Feeling then the internal liquors and spirits of the body are wont to do and so it would appear actually cold Nor is it necessary that all liquors much less all fluids should be as much agitated as the blood and vital humors of a humane body as we see to omit what in the last Section is mention'd about newly emitted Urine and to skip other obvious instances in those Fishes and other Animals whose Blood and analogous Juices are always and that in the state which passes for their natural state actually Cold to our Touch. And I see no sufficient reason why we should not conceive the Air even in its natural state at least as far forth as it can be said to have a natural state to be one of the number of cold Fluids For as to the main if not only Argument of Gassendus and others namely That as we see the Air to be easily heated by the Action of the Sun or the fire so we see it as easily refrigerated by ice and snow and Northerly winds and other Efficients of Cold and that heat and cold reign in it by turns in Summer and in Winter This only proves what I readily grant that the Air is easily susceptible at several times of both these contrary Qualities but it does not shew that one is not more connatural to it then the other as we see that the water may be easily depriv'd of its fluidity by the circumposition of snow and salt and reduc'd to be fluid again by the Sun or the Fire and yet according to them as well as others fluidity not Firmness is the natural quality of water But this is not that which I lay most weight upon for I considered that it is manifest and acknowledg'd by these learned Men themselves that the heat of the Air is adventitious to it and communicated by the beams of the Sun or of the Fire or by some other Agents naturally productive of heat as well in other Bodies as the Air And 't is also evident that upon the bare absence for ought else that appears of the Sun or Extinction of the Fire or removal of the other causes of heat the Air will as it were of its own accord be reduc'd to Coldness Whereas that there are swarms of frigorifick Atoms diffus'd through the Air from which all its coldness proceeds is but an Hypothesis of their own far from being manifest in it self and not hitherto that I know of prov'd by any fit Experiment or cogent reason And though in some cases I am not adverse to the admitting such Corpuscles as may in a sense be styl'd frigorifick yet I see not why we should have recourse to them in cases where such a bare cessation or lessening of former motion as may easily be ascrib'd to manifest causes may serve the turn as to a Sensible for
Sections of this Historical Treatise all the Particulars that I knew to belong to so comprehensive a Theme as would readily appear if I thought it convenient to insert here the Scheme of Articles of inquiry that I drew up to direct my self what inquiries and Experiments to make But though there were divers of those Heads to which I could say so little that I judg'd it improper to assign them distinct Titles because as to some of them I had not time and opportunity to make those Trials which if I had not wanted those Requisites might have been made even here in England and because also as to more of them I conceiv'd my self unable to produce in this temperate Climate so strong and durable a Cold as seem'd necessary to make the trials that might be referr'd to them succeed so far as to satisfie my doubts either affirmatively or negatively Though I say these and some other Considerations kept me from increasing the Number of the Titles among which I have distributed the Experiments and Observations that make up the foregoing part of this Treatise yet since divers particulars have occurr'd to me which though they seem not properly reducible to the foregoing Titles do yet belong to the subject and design of this Treatise I think it fit to annex them in this place and without any other order then that wherein they shall happen to occur to me throw them into this one Section together with some loose Experiments and divers Relations that I have met with among Navigators and Authors that have travell'd into the Northern Climates touching Cold not forbearing to insert promiscuously among them some few Paralipomena which if they had seasonably come to my hands or into my mind might have had a more proper place among the foregoing Sections or have composed a Title by themselves Wherefore though the Observations will not be altogether unaccompanied with Experiments yet for the reasons above intimated much the greater part of what is to be deliver'd under this Title will consist of Collections out of Voyages in which the strange things mention'd being such as we cannot examine by our own Trials I can equitably be thought answerable for the Truth of nothing but the Citations 2. I remember I tri'd at several times divers Experiments to discover whether or no congelation would by constriction of the pores of Bodies or vitiating their Texture or arresting the motion of their parts hinder them from emitting those Effluvia that we call odors but the Register of these Observations being unhappily lost in one of my late removes I dare add but these few wherein I have no cause to distrust my memory 3. I did in the Moneths of December and January at several times gather differing sorts of flowers in frosty weather but in most when they were freshly gather'd and hastily smelt to I could scarce perceive any sensible smell whether it were that the causes above hinted hinder'd the expiration of the odoriferous steams or that the cold had some undiscerned influence upon the Organ of smelling which made the sense more dull or that the same cold kept the Alimental juice of the flowers from rising in such plenty and abounding so much with spirituous parts as was usual at the more friendly seasons of the year and this seem'd the more likely to be one reason of the Phaenomenon because most of the flowers were flaggy and as it were ready to wither and because also a Primrose that was vigorous and fresh in its kind had an odor that was manifestly and 't will easily be believ'd that it was not strongly sweet and genuine 4. I took also about an ounce by guess of Rose-water and putting it into a small vial after I had smelt to it it was expos'd to freez in the open Air and when it began to have ice in it I then smelt to it again but found not the perfume considerably if so much as manifesty abated and lastly having suffer'd it to continue in the Air that was then very sharp till 't was quite frozen and discover'd no liquor when the vial was turn'd upside down the ice notwithstanding was not distitute of a graceful and genuine sent though it seem'd somewhat faint but after the ice was reduc'd to water again the fragrancy appear'd considerable But on this occasion 't will not be improper to subjoyn this Caution That care must be had in Trials of this Nature to make ones estimate betimes for if a man should stay too long about it there is danger that the warmth of ones breath and face may relax the pores or thaw the surface of the ice that is held near his Nose and both free and excite the Corpuscles of smell that are imprison'd there that so instead of ice he may smell a liquor The reasonableness of which advertisment may be justifi'd by an Experiment that I am about to annex For being pretty well confirmed by the casual and unwilling Observations of one of my friends curious in making sweet water That even Liquors more easie to be spoilt then Rose-water would not have their fragrancy destroy'd though perhaps impair'd nor so much as their odors for the time quite imprison'd and suppress'd by congelation and this appearing congruous to what I formerly noted of the Effluviums that may by the Decrement of weight be gathered to issue from ice it self I thought it worth while to try whether stinking Liquors would not be more alter'd by congelation then odoriferous ones and accordingly having procur'd some rain water that had been kept in a Tub till it stunck so strongly that I could hardly endure it near my nose I caus'd a pottinger 〈◊〉 of it to be expos'd all night to a very sharp Air and examining it the next morning when it was all turn'd into ice neither I nor some others to whom it was offer'd could perceive any stinck at all in it and having in another place but with as stinking water repeated the Experiment when the pottinger was the next morning brought to my beds side I found it to smell abominably whereupon guessing that this difference proceeded from some thaw made by the warmth of the room in the superficial parts of the ice I found it to be so indeed partly by the help of the light which discovered a little liquor upon the ice and partly by exposing the vessel with that liquor in it to the cold Air again by whose operations an ice was produc'd that was perfectly inodorous and I remember that one of these parcels of ice being thaw'd seem'd to be less stinking then before it had been frozen and if I had not been diverted I should have tried whether this ice that did not emit odors would emit like other ice Effluvia discoverable by the Scales for whether the ice would lose of its weight which seem'd the more probable or would not the event may afford a not inconsiderable hint 5. It is a thing not only remarkable
in Winter a cold Northerly wind froze the water without doors it was not less cold in Wine-Cellars then 't was at the same season and at the same hour of the day in his Study only the Paper-shuts of his window that regarded likewise the North being put to And though if he had said nothing else I should have suspected that this might have proceeded from the shallowness of the Cellars he made his Trial in yet he prevents that suspicion by taking notice in one clause of his Relation that the Cellars were of the very best of their kind in which in Summer the greatest Cold was wont to be felt But his next Experiment is yet more considerable which I shall therefore deliver in his own words that follow Expertus ego sum says he Thermometro fidelissimo à praecedente hyeme in sequentem aestatem prorsus invariato instructo etiam tali aquâ nempe in hoc ipsum ex praescripto Trebellii it a comparata ut non exhaletur neque minuatur expertus inquam sum in supradictis optimis Cellis Vinariis maximum quod ardentissima aestate fuit frigus non adaequasse illud quod ibidem erat brumali tempore ut dixi in superiori Experimento siquidem in Tubo Vitrei Thermometri quatuor circiter palmos longo in octo gradus Graduumque minuta diviso aqua byeme ascendit ad gradus 7. cum semisse aestate autem vix gradum Sextum super avit cum tamen ad sensum multo magis vigeret frigus istud 〈◊〉 Thus far this learned as well as resolute Author who seeming by the Mathematical part of his Perspectiva Horaria to be an accurate and industrious maker of observations we may oppose his newly recited Experiment to that of Zucchius which it flatly contradicts and therefore since the depth of the Cellars is of great moment in Experiments of this Nature since also the particular Nature of the place or soil where the Cellar or other Cavities happen to be may in some cases not be inconsiderable and since lastly neither Zucchius nor Maignan seem to have been aware of the differing weights of the Atmosphere in the self same place as not having seen the XVIII of our Physico-mechanical Experiments before which I never saw nor heard of any thing publish'd or otherwise written to that purpose I hope I shall be excus'd if I retain some scruples about the Historical Question I have been considering till the Experiment have been carefully made for a competent space of time in several places and that not with common Weather glasses like those us'd by my two learned Authors wherein the liquor may be made to rise and fall by the differing gravities of the Air but with seal'd Thermoscopes wherein the alterations may more safely be suppos'd to proceed only from its heat and cold And to conclude since Carneades has speciously enough answered the other Observations that are wont to be produc'd in favour of the Aristotelian Antiperistasis if Maignans relation be better warranted by future Experiments then that of Zucchius it will very much disfavour the whole Doctrine it self which seeming to have been devis'd but to give an account of the Phaenomena to which 't is wont to be appli'd considering men will be but little invited to imbrace it if the matter of fact be as little Certain as what is propos'd in the Hypothesis is Intelligible FINIS AN EXAMEN OF Mr. Hobs's Doctrine touching Cold. 1. Mr. Hobs's Theory concerning Cold does to me I confess appear so inconsiderately pitch'd upon and so slightly made out that I should not think it merited especially in an Historical Treatise a particular or sollicitous Examination but that in proposing it he scruples not to talk to his Readers of his Demonstrations and the preferrence he is wont to give himself above the Eminentest as well of Modern as of Ancient Writers has had no small effect upon many who not knowing how indulgent some writers are wont to be to the issues of their own brain as such are apt to mistake Confidence for Evidence and may be modest enough to think that their not discerning a clearness in his Explications and Reasonings is rather the fault of their Understandings then of his Doctrine Mr. Hobs delivers his Theory in the seven first Articles of the 28. Chapter of the fourth part of his Elements But because the whole discourse is too long to be here transcrib'd and because in the 2 3 and 4. Sections that which he treats of is the generation of winds and that which he handles in the fifth is the notion of a hard body we may safely leave out those four Sections especially since though there be in them divers things about the motion of the Sun and other matters that are more strongly asserted then prov'd yet his doctrine tending but to shew how the winds are generated though it were granted would make but very little if any thing at all towards the evincing of his Theory about cold 2. And that we may not be suspected to injure his opinion or his arguments we will though the Citation will be somewhat prolix first recite them as himself delivers them in those three Sections that treat immediately of Cold and then we will subjoyn our Animadversions on them 3. These things says he being premis'd I shall shew a possible cause why there is greater cold near the Poles of the Earth then further from them The motion of the Sun between the Tropicks driving the Air towards that part of the Earths superficies which is perpendicular under it makes it spread it self every way and the velocity of this expansion of the Air grows greater and greater as the superficies of the Earth comes more and more to be straitned that is to say as the Circles which are parallel to the Aequator come to be less and less Wherefore this expansive motion of the air drives before it the parts of the air which are in its way continually towards the Poles more and more strongly as its force comes to be more and more united that is to say as the Circles which are parallel to the Aequator are less and less that is so much the more by how much they are nearer to the Poles of the Earth In those places therefore which are nearer to the Poles there is greater cold then in those which are more remote from them Now this expansion of the air upon the superficies of the Earth from East to West doth by reason of the Suns perpetual accession to the places which are successively under it make it cold at the time of the Suns rising and setting but as the Sun comes to be more and more perpendicular to those cooled places so by the heat which is generated by the supervening simple motion of the Sun that cold is again remitted and can never be great because the action by which it was generated was not permanent Wherefore I have rendred a
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
condens'd by Cold. The III. Discourse Containing The II. Paradox Viz. Touching the Cause of the Condensation of Air and Ascent of Water by Cold in Common Weather-glasses THough I thought here to end the Praeliminary Discourse as doubting it may be thought prolix enough already yet for confirmation of what I was lately noting about the incompleteness of the Theory of Cold and because the evincement thereof may give rise to many Trials that may inrich the History of Cold I will here subjoyn a Discourse formerly written on another Occasion For though upon that Account I am fain to leave out the beginning of It as not suted to the present Occasion yet the main Body of the Discourse may be I think not improperly annex'd to what has been already said about Weather-glasses since it examines the causes of the principal Phaenomenon of them and will perhaps help to discover the incompleteness of mens Notions about Cold by showing that the true cause ev'n of the most obvious Phaenomenon of Common Weather-glasses though almost every man thinks he understands It has not yet been sufficiently inquir'd into The discourse then that first part of It as forreign to our present purpose being omitted is as follows To prosecute our Disquisition satisfactorily it will concern us to consider upon what Account the water rises in Cold Weather and falls in Hot in common Weather-glasses whose Construction being so well known that we need not spend time to set it down we may forthwith proceed to take notice That concerning the reason why in these Weather-glasses the water or other Liquor in the shank or pipe ascends with Cold and descends with Heat there are three opinions that will deserve our Consideration The first is the common opinion of the Schools and Peripateticks and indeed of the generality of learned Men of differing Sects who teach that the Cold of the External Air contracting the Air included in the Weather-glass and thereby reducing it into a narrower Room then formerly it possest the water must necessarily ascend to fill the place deserted by the retired Air lest that space should become a vacuum which Nature abhors But against this Explication we have several things to object For first I am not satisfi'd that any of the Schoolmen or Peripateticks at least of those I have met with have solidly evinc'd that Nature cannot be brought to admit a vacuum Nor do I much exspect to see that assertion well prov'd by these or by any other that forbear to make use of the Argument of the Cartesians drawn from the Nature of a Body whose very essence they place in its having extension which I say because about this Argument I neither have yet published nor do now intend to deliver my thoughts Next it seems a way of Explicating that little becomes a Naturalist to attribute to the senseless and inanimate Body of water an Aim at the good of the Universe strong enough to make it act as if it were a free Agent contrary to the tendency of its own private Nature to prevent a Vacuum that as is presum'd would be hurtful to the Universe But these Arguments we have elsewhere urg'd and therefore need not insist longer on them here Thirdly if you take a Bolthead with a large Ball and long stem and do with that and Quicksilver make the Torricellian Experiment there will be an Instrument prepar'd like a Common Weather-glass save that the stem is longer and that the Liquor is Mercury instead of Water and yet in this case we see not that the Mercury which remains pendulous in the pipe at the height of about 30. Inches offers to ascend into the cavity of the Bolthead to fill up the space whence the Air was expell'd by the Mercury and which the Quicksilver also by its subsiding deserted And the outward application of Cold Bodies to the 〈◊〉 part of the head will not perhaps Occasion the rising of the Quicksilver a ¼ of an Inch is half so much though the like degree of Cold would make the water ascend in a Vulgar Thermometer though shorter to the height of several Inches But this Argument I also on another Occasion further display and vindicare Wherefore I shall add one more taken from the Consideration of these seal'd Weather-glasses that are describ'd in this 〈◊〉 History of Cold. For in these the Air does not shrink but rather seems to be expanded when the weather grows Colder If it be said that water being contracted by the Cold the Air follows it to prevent a Vacuum I answer that those that say this should explain why whereas in Common Weather-glasses the water ascends to follow the Air in these the Air must descend to follow the water And why since to avoid a Vacuum the one in common Weather-glasses and the other in seal'd ones resists contraction Nature does not rather make the Air in Common Thermometers retain the extension they conceive due to its nature then put her self to the double Labour of suffering the Air to be preternaturally condens'd and compelling the water to ascend contrary to its nature But these Arguments I will not urge so much as this other that in our present case the above propos'd Answer will by no means salve the difficulty For if the water be really condens'd into less and the Air expanded into more space then they respectively possest before I see not how a Vacuum or a worse Inconvenience will be avoided for I demand since Glass is granted to be impervious to Air and water as indeed else Nature would not need to make water ascend contrary to its own tendency in a Common Weather-glass what becomes of the Body that was harbour'd in the space deserted by the water upon its Condensation Which Question those that do not say any thing escaped away through the Glass or that any thing was annihilated will not easily answer But this is not all for I further demand when the Air expands it self to follow the water how by that expansion of the Air a Vacuum both coacervatum as the old Epicureans spoke and interspersum is avoided For the aerial Corpuscles cannot advance into this space deserted by the water without leaving either in whole or in part the spaces they fill'd before so that by this remove an aerial Corpuscle only changes place but does not adequately fill any more place then it did before But if it be said that the same Air without any substantial Accession may adequately fill more space at one time then at another If this I say be pretended I shall not urge that it appears not why it were not more easie for Nature in common Weather-glasses as well as in seal'd ones to rarifie the Air which they reach to be so very easily rarifi'd and condens'd then to make the heavy Body of water to ascend For I may very well reply that I scarce know any Opinion in Natural Philosophy that to me seems more unintelligible and more worthy to be
confidently rejected then This harsh Hypothesis of Rarefaction Of which I should think it injurious to so judicious a Philosopher as my Lord Brouncher to indeavour here to manifest the absurdity though I had not in another place shewn it already The next Opinion we are to consider touching the cause of the ascension of Water by cold in Weather-glasses is that of Mr. 〈◊〉 who in the last Chapter of his Book de Corpore Sect. the 12. having premis'd a delineation of a common Weather-glass subjoyns this Explication In the sixth and seventh Articles of the 27. Chap. where I consider the cause of Cold I have shewn that fluid Bodies are made colder by the pressure of the Air that is to say by a constant wind that presseth them For the same cause it is that the superficies of the water is press'd at F and having no place to which it may retire from this pressure besides the Cavity of the Cylinder between H and E it is therefore necessarily forced thither by the Cold and consequently it ascendeth more or less according as the Cold is more or less increas'd And again as the Heat is more intense or the Cold more remiss the same water will be depress'd more or less by its own gravity that is to say by the cause of gravity above explicated But however the Author of this Explication to prepare us to receive it tell us that however the above mention'd Phaenomenon be certainly known to be true by experience the cause nevertheless has not yet been discover'd yet I confess I think this newly recited assertion might as well have been plac'd after his explication as just before it For first whereas he remits us to the sixth and seventh Articles of the 27. Chapter for the reference is misprinted as containing the grounds of this Explication I must profess my self far from being satisfi'd with the general Theory of Cold deliver'd in that Chapter as being partly precarious partly insufficient and partly scarce intelligible as I shall elsewhere have Occasion to shew and as for what he particularly alledges in the sixth and seventh Articles of a constant wind that presses fluid Bodies and makes them Cold besides that that is prooflesly affirm'd we shall anon have Occasion to mention an Experiment where water was not only much refrigerated but turn'd into Ice though it were seal'd up in Glass Vessels and those suspended too in other Glasses wherein some of them had Air about them and some others were totally immers'd in unfreezing Liquors so that the water that was seal'd up was sufficiently protected from being raked by the wind as Mr. Hob's conceipt of the Cause of freezing requires Secondly I see no necessity that the Cold should press up the superficies of the Water into the shank of the Weather-glass especially since 't is manifest that the Water will rise with Cold in a Weather-glass kept in a still place and free from any sensible wind Besides that it should be prov'd and not barely affirm'd that an insensible Motion deserves the name of wind and that such a one is the cause of the refrigeration of water and it should be also shewn how this wind comes to be able to raise the water and that to the height of many Inches more in one part of the superficies then in another Besides all this I say we find by Experience that Water powred into a Bolthead till it have fill'd the Ball and reach'd a good way into the Stem will upon a powerful refrigeration short of freezing which is the case of water in Weather-glasses when the Air grows colder manifestly shrink into a narrower room instead of being impell'd up higher in the Pipe And if in an ordinary Weather-glass with a long shank you apply a mixture of Ice or Snow and Salt to the Bolthead the water will readily ascend in the shank to the height of divers Inches which how it will be explain'd by Mr. Hob's Hypothesis I do not well see Thirdly I wonder he should tell us that the reason why the press'd water ascends into the shank of the Weather-glass is because it hath no other place into which it may retire from the pressure of the wind since he rejecting a Vacuum and affirming the world to be every where perfectly full should not methinks have so soon forgotten that in the very Paragraph or Section immediately preceding this himself had told us that he cannot imagine how the same place can be always full and nevertheless contain sometimes a greater sometimes a less Quantity of matter that is to say that it can be fuller then full So that I see not why the water should find more room to entertain it in the Cylindrical cavity of the Weather-glass already adequately fill'd with Air then otherwhere And in the seal'd Weather-glasses we have above been mentioning and wherein the water descends with Cold 't will be very hard for Mr. Hobs to make out the Phaenomenon according to his doctrine Besides that his Explication gives us no account of the Condensation of the Air by cold in such Weather-glasses as those wherein the water descends with Cold and rises with Heat Fourthly and lastly whereas Mr. Hobs takes notice of no other cause of the 〈◊〉 of water in Weather-glasses by Heat but it s own gravity he seems to have but slightly consider'd the matter For though in some cases the gravity of the water may suffice to depress it yet in other cases that gravity alone will by no means serve the turn but we must have recourse to the expansive Motion or spring of the Air included in the Cavity of the Glass For if you place a Thermometer with a large Ball wherein the water ascends but a little way into the shank in a window expos'd to the warm Sun you will often perceive the surface of the water in the Pipe to be a good deal lower then that of the water on the outside of the Pipe which shews that this depression proceeds not from the bare sinking of the water but from its being thrust down by the pressure of the incumbent Air since the waters own weight would make the internal water fall but to a level with the surface of the external water and not so much beneath it And for further proof you may by keeping such a Weather-glass long enough in the hot Sun bring the Air so far to expand it self as to drive the water out of the shank and break through the external water in divers conspicuous Bubbles after whose eruption the remaining Air being again refrigerated by the removal of the Weather-glass into a cooler place the loss of that part of the Air that escap'd away in Bubbles will make the water ascend higher in the shank then in the like degree of Cold it would formerly have been impell'd And thus much may suffice to shew the unsatisfactoriness of Mr. Hob's conceipt The third and last opinion we shall mention is that of some
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
as it could to its temper and consequently to the same temper as to heat and cold and then with the warmth of ones hand the included ice being loosened from the glass as it was taken out and a ruler divided into inches and eights being laid alongst it with a knife a little warmed the ice was soon and yet not carelesly divided into several small Cylinders of three quarters of an inch a piece and these Cylinders thus reduced to as sensible an equality as we could were nimbly and carefully put into the several liquors hereafter to be mentioned and whilest we our selves watched very attentively till each of these icy Cylinders was quite and yet but just dissolved we caused others to keep time by the help of a Pendulum whose Vibrations were each a second minute or 60. part of a Common Minute whereof 60. go to make an hour and it was easie for those we appointed to watch the Vibrations of the Pendulum notwithstanding the Quickness of its Motion because it was fitted to a little Instrument purposely contrived for such nice observations wherein a long Index moving upon a divided Dyal plate did very manifestly point out the number of the Diadromes made by the Pendulum 3. This Experiment was afterwards repeated twice with Cylinders of ice each of them an inch long and though the successes of these trials were various enough yet we shall subjoyn both the last as being made with more advantage then the first that the more light may be gathered from them and that at least we may discover how difficult it is to make such Experiments in this matter as that all the nice circumstances of them may safely be relied on I. Trial. 1. Oyl of Vitriol where a Cylinder of Ice of an iuch long being put into lasted 5. minutes 2. Spirit of Wine in which the ice sunk lasted 12. minutes 3. Aqua fortis lasted 12 ½ minutes 4. Water lasted about 12. minutes 5. Oyl of Turpentine lasted not good 44. minutes 6. Air lasted 64. minutes II. Trial. 1. In Oyl of Vitriol where an inch of Cylindrical ice lasted 3. minutes 2. In Spirit of Wine lasted 13. minutes 3. In Water lasted 26. minutes 4. In Oyl of Turpentine lasted 47. minutes 5. In Sallet Oyl lasted 52. minutes 6. In the Air lasted 152. minutes 4. We likewise thought it worth trying whether there would be any difference and how much difference there would be in the Duration of pieces of ice of the same bulk and figure some of them made of common water and others of frozen Wine Milk Oyl Urine and other spirituous liquors these several pieces being exposed to be thaw'd in the same Air or other ambient liquor 5. We also tried whether Motion would impart a heat to ice by nimbly rubbing a strong piece of ice upon a plate of ice and though this seemed to hasten the dissolution in that part of the icy plate where the Altrition had been made yet we were unwilling to determine the matter till further and exacter trial have been made 6. And this brings into my mind an Experiment that has by some been thought very strange The occasion I remember was that I received the last Winter the honour of a visit from a Nobleman of great eminency and learning who chancing to come in while I was making some trials with ice would needs know what I was doing with it but the presence of a very fair Lady in whom Hymen had made him happy and of some other Company of that Sex that he brought along with him inviting me to give him the answer that I thought would be most suited and acceptable to his Company I merrily told him that I was trying how to heat a Cold liquor with ice and to satisfie him that was no impossibility I held out an open mouth'd glass full of a certain liquor which for some just reasons I do not describe but do plainly teach it in an opportuner place and desired them to feel whether it were not actually Cold and when they were satisfied it was so I chose among the pieces ofice that lay by me that I judg'd by the eye to be fit for my purpose for every piece was not so for a reason I elsewhere shew and throwing it into this liquor it did not only in a trice vanish in it but the Lady I was mentioning seeing the liquor smoak and advancing hastily to try whether it were really warm found it so hot that she was quickly fain to let it alone and had almost burnt her tender hand with which she had in spight of my 〈◊〉 wasion taken hold of the glass which Her Lord himself could 〈◊〉 indure to hold in his But this Experiment which for the main I have repeated before competent witnesses though it be not impertinent to the History of Cold yet I shall not build much upon it because how strange soever many have been pleased to think it I shall elsewhere shew that I made use of a certain unperceivable slight which in my opinion did as well as the nature of the liquor and the texture of the ice contribute to the suddenness and surprizingness of the Effect 7. But to return to the duration of the effects of Cold I think those much mistaken who imagine that the effects of Cold do continually depend upon the actual presence and influence of the manifest efficients as the light of the Air depends upon the Sun or Fire or other luminous body upon whose removal it immediately ceases For when cold agents have actually brought a disposed subject to a state of congelation though the manifest efficient cause cease from acting or perhaps from being the effect may yet continue For in most cases if a certain texture be once produced in a body it is agreeable to the constancy of nature that it persevere in that state till it be forceably put out of it by some agent capable to overpower it and though we usually see ice and snow as it were of their own accord to melt away when the frosty constitution of the Air ceases yet the cause of that may be not barely the cessation of frosty weather but that those easily dissoluble bodies are exposed to the free Air which being heated by the Sun beams and perhaps by calorifick expirations from the earth is furnisht with an actual cause upon whose account it destroys the texture of the ice and snow but even here above ground if snow be well compacted into great masses in which by reason of the closeness of the little icickles but little Air is allowed to get between them I have seen such masses of snow last so long not only in thawing but in rainy weather as to be wondered at and if such snow or ice be kept in a place where it may be fenced from the Sun and other external enimies though the place it is lodged in be not any thing near cold enough to produce ice yet it will as some trial
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
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
that treats of ice Yet two or three notable instances which we do not elsewhere mention 't will not be improper to deliver in this place 7. The first declares that notwithstanding the warmth of the inside of a mans mouth his spittle may be frozen even there The 27. of September they are the words of Gerat de Veer it blew hard Northeast and it froze so hard that as we put a nail into our mouthes as when men work Carpenters work they use to do there would Ice hang thereon when we took it out again and make the blood follow The like relation if I misremember not I have met with in a modern English Navigator and it is very little if at all more strange then what is affirm'd by Queen Elizabeths Ambassador to the Russian Emperor In the extremity of winter says Doctor Fletcher speaking of Muscovia if you hold a pewter Dish or Pot in your hand or any other mettal except in some chamber where their warm Stoves be your fingers will stick fast to it and draw off the skin at the parting 8. The other instance I intended to mention is this that though Macrobius and other learned men both ancient and modern will not allow salt water to be congealable yet the Dutch at Nova Zembla relate that even in the midst of September and a the Marginal note says in a night It froze two inches thick in the salt water 9. As to the effects of violent colds upon the Earth what they would prove upon pure and Elementary Earth if any such there be I can but conjecture but as for that impure or mingled Earth which we commonly tread on the effects of extreme cold upon that may be very notable For Olearius relates that in the year 1634. the cold was so bitter at Musco that in the great market-place he saw the ground open'd by it so that there was made a cleft of many yards long and a foot broad And the present great Duke of Muscovies Physician being asked by me concerning the truth of such relations answered me that he himself had in those parts seen the ground reduc'd by the cold to gape so wide that a childs head might well have been put into the cleft 10. 'T is somewhat strange that the violent heat of Summer and the extreme cold of Winter should both of them be able to produce in the ground the like effects but whether to make these gaping chinks that we have been speaking of the surface of the ground expos'd to the air being first frozen is afterwards broken by the expansive force of the moist earth underneath to which the cold at length pierces and congealing it makes it swell and heave and so burst or cleave the hard and frozen crust of the ground which cannot sufficiently yield to it whether this I say may produce the clefts we were speaking of or whether they must be deriv'd from some other cause not having yet made the experiments I thought upon to clear the matter one way or other I do not as yet pretend to determine but will rather subjoyn the second observation I purpos'd to mention of a strange operation of Cold upon the ground and it is afforded us by the Dutch in their often quoted third voyage to Nova Zembla In one place of which they tell us That when they had built them a wooden house and were going to shut themselves up in it for the winter they made a great fire without the house therewith to thaw the ground that they might so lay it viz. the wood about the house that it might be the closer but it was all lost labour for the earth was so hard and frozen so deep into the ground that they could not thaw it and it would have cost them too much wood and therefore they were forced to leave off that labour 11. After what we have said about the strange effects of cold in reference to fire air water and earth we will now proceed to take notice of its effects upon confessedly compounded Bodies whether inanimate or living but of the former sort of mix'd Bodies I mean those that have not Life it will not be necessary to say much in this Section in regard that we have in many other places upon several occasions had opportunities to mention already most of the particulars that belong to that head For we elsewhere take notice that violent Colds will freez Beer Ale Vinegre Oyl common Wine and even Sack and Alegant themselves We have likewise noted that the Cold may have a notable operation upon Wood Bricks Stone vessels of Glass Earth and even Pewter and Iron themselves to which Bartholinus out of Janus Muncks Voyage to Greenland allows us to add vessels of Brass though these are not immediately broken by the Cold but by the included Liquors which it dilates and divers strange effects of Cold upon inanimate Bodies which 't were here troublesome to recapitulate may be met with dispers'd in several places of the present History Wherefore having only intimated in general that though many plants are preserv'd by a moderate cold yet it has been observ'd that most Garden-plants are destroy'd by excessive degrees of it we will pass on to consider the effects of Cold upon animals and of the many observations that we have met with among Travellers concerning this subject we shall to avoid prolixity deliver only the considerablest and those that we find attested by very credible Writers 12. Captain James speaking of the last of the three differences he makes of Cold namely that which he and his company felt in the woods gives this account of it As for the last it would be so extreme that it was not endurable no clothes were proof against it no motion could resist it It would moreover so freez the hair of our Eye-lids that we could not see and I verily believe that it would have stifled a man in a very few hours 13. Olearius giving an account of the Air of Muscovy and especially the Capital City of it The Cold says he is there so violent that no Furs can hinder it but sometimes mens Noses and Ears Feet and Hands will be frozen and all fall off He adds that in the year 1634. when he was there they could not go 50. paces without being benumm'd with cold and in danger of losing some of their Limbs And yet to add that remarkable observation upon the by the same Author near the same place speaking of Musco and the neighbouring Provinces distinguished from the rest of that vast Empire says That the Air is good and healthy so that there one scarce ever hears of the Plague or any other Epidemical diseases And he adds that for that reason when in the year 1654. the Plague made havock in that great City the thing was very surprizing nothing like it having been seen there in the memory of men 14. Our already divers times mention'd English
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
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
readily diffus'd in imperceptible particles through the air And I have observed upon the opening of issues in some mens arms that though no smoak be visible in Summer it will be very conspicuous in exceeding sharp weather though mens arms at least the external parts of them seem to have less heat in frosty weather then in Summer since in the former of those seasons they are wont to be manifestly more slender the fleshy parts and juices being condensed by the coldness of the Air. And though the insensible Transpirations that continually exhale from all the parts of our bodies are not wont to be visible here even in Winter yet in extremely cold Countries as Nova Zembla or Charleton Island those Effluvia have been observ'd not only to be thickned but to be turned into ice it self sometimes within the Sea-mens shooes And here in England having not long since imployed a labouring man to dig a deep hole in very frosty weather two Servants of mine that stood by to see him work did both of them assure me when they return'd that the steams of his heated body were frozen upon the outside of his Wastcoat which one of them whilest the other was about to give me notice of it inconsiderately wip'd off 43. And since we see how fast the water in Ponds and Ditches wastes and decreases in Summer there is no cause to doubt but that it does then continually emit Exhalations as well if not much more 〈◊〉 then in Winter which may be manifestly confirmed by this that in the Summer one shall often see in the mornings or evenings the face of the water cover'd with a mist or smoak that rises out of it And I have sometimes taken pleasure to see this aggregate of Exhalations hover over the water and make as it were another River of a lighter liquor that conform'd it self for a considerable way to the breadth and windings of the stream whence it proceeded And I think it will be easily granted that the water in Summer time is at least as warm at noon when such Exhalations are not visible as in the morning when they are though the Air be colder at this part of the day then at that which observation gives us the true reason of the Phaenomenon 44. And though notwithstanding all this it were made to appear that in some cases the smoaking water of Springs may be really warmer in Winter then in Summer yet a sufficient reason of the Phaenomenon may be fetch'd from what I have already delivered about the detention of the warm subterraneal vapours by the frost and snow and rain that make the earth less perspirable in Winter 45. And because I know Themistius will look upon a thing so disagreeable to the vulgar opinion Of the Coldness of the whole Element of Earth as a Paradox I will take this opportunity to add a further confirmation to what I have been saying 46. And first that there arise copious and warm steams from the lower parts of the Earth may be prov'd not only by what I have already mentioned touching the Hangarian Mines but by the common complaint of Diggers in most though not in all deep Mines That they are oftentimes troubled and sometimes endangered by sudden damps which do frequently so stuff up and thicken the subterraneal Air that they make it not only unfit for respiration but able to extinguish the Lamps and Candles that the Miners use to give them light to work by And I remember that I have visited Mines where having inquired of the diggers whether those hot exhalations that compose their damps did not sometimes actually take fire within the bowels of the Earth I was answered that in some of their Pits and particularly in one that they show'd me though not in all they did insomuch that the exhalation suddenly kindling would make a report at the mouth of the Pit like a Musquet or a small piece of Ordinance and the flame would actually burn off the hair and scorch the skins of 〈◊〉 workmen that did not seasonably get out of the Pit when the exhalation appear'd to be near an ascension or did not nimbly fall down flat with their faces to the ground till the flame was gone out And one of these workmen that I ask'd affirm'd himself to have been several times to his no small trouble so burned and that if I much misremember not twice in one day And it seems to me as well as to Morinus very probable that those great quantities of rain and snow and storms and perhaps some other Meteors that are taken notice of in Winter may rather consist of these subterraneal steams then the vapours and exhalations attracted by the Sun or at least may as much consist of the former as the latter For his heat is then very languid and acts upon the ground but during the day time which is very short whereas those Meteors are generated indifferently at all hours of the day and night and the sky is oftentimes for many days together quite overcast with clouds and the surface of the ground so constipated with frost that it will sometimes freez even in the Sun-shine So that 't is not near so likely that the heat of the Sun in the midst of all these disadvantages should be able to elevate so great a plenty of exhalations and vapours as are requisite to compose the rain and snow and storms that sometimes last almost all the Winter as that they should be suppli'd by subterraneal steams copiously sent up from the heat that continually reigns in the lower parts of the Earth and by traversing the Sea and at other vents get up into the Air. 47. To make out this my formerly quoted French Author relates a very memorable thing that was told him by the Masters of those Mines in Hungary which are at least as deep as any that I remember I have seen or read of namely that the Miners were able certainly to foretel sooner then any other mortals the Tempests and sudden mutations that were to happen in the Air. For when they perceived by the burning blew of their Lights and by other manifest signs that they could easily take notice of in their Grooves that store of the Tempestuous Damp if I may so call it was ascending from the lower parts of the Earth though the sky above were clear and the Air calm yet they conld assuredly foretel the approach of a storm or some other great alteration in the Air which would accordingly ensue within no very long time aster And to confirm this Narrative I shall add not only that 't is agreeable to what I lately told you was affirm'd to me by other Mine-men but that having enquir'd of a very ingenious Physician who liv'd many years in Cornwall a Country you know famous for Tin-Mines some of which are infamous for the damps that infest them he told me that divers of the experienced Fishermen assur'd him that oftentimes they did perceive
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