fires shining in the night sometimes in one place sometimes in another which were suppos'd to be kindled by the sulphurous and other subterraneous exhalations and that when they perceiv'd those fires especially if any number appear'd in several places those that were well acquainted with the coast would not continue long out at Sea but rather quit an opportunity of catching Fish then not make seasonably to the shore having often observed and particularly this last year that bold and unexperienced Mariners by slighting these forerunners of storms were in few hours shipwrack'd by them 48. To this I shall add what happened some years since upon the Irish coast near a strong Fortress called Duncannon where divers of the ships Royal of England lying at anchor in a place where they apprehended no danger from the wind there seem'd suddenly to ascend out of the water not far from them a black cloud in shape and bigness not much unlike a Barrel which mounting upwards was not long after follow'd as the most experienced Pilot foretold so hideous a storm as forc'd those ships to go to Sea again and had like to have cast them away in it And this account was both written by the principal officers of the Squadron to their superiors in England and given soon after it happened by the chief of those eye-witnesses and particularly by the Pilot to a very near kinsman of mine well vers'd in Maritine affairs that commanded the land forces in those parts as a truth no less known then memorable 49. And on occasion of what I was saying about the eruption of hot steams in several parts of the Earth I now call to mind something that I have met with in a very small but curious Dissertation De admirandis Hungariae aquis whose Anonymous Author I gather from some passages in the Tract it self to have been a Nobleman Governor of Saros and some other places in Hungary and to have written this discourse both for and to that inquisitive German Baron Sigis mundus Liber famous for the account he gave the world of the Ambassy whereon he was sent by the German to the Russian Emperor This Anonymous but noble writer tells us then that in that part of Hungary which he calls Comitatus Zoliensis there is a gaping piece of ground which does emit such mortal exspirations that they suffocate not only Cats and Dogs purposely held at the end of long poles over the cleft but kill even Birds that attempt to fly over it And in other places of the same Tract I have met with many other relations which if I had time to make a particular mention of would much countenance what I have been lately saying but though I pretermit several other instances I cannot but take especial notice of one which together with what I lately mention'd to have happened near Duncannon may make it probable that not only under the surface of the dry ground but in that part of the Terrestrial Globe that is covered with water there may arise streams and consequently Exhalations actually and that considerably hot For in one place he takes notice that not far from the well known City of Buda there is a hot Spring which they call Purgatory which the waters of Danubius it self are not able to keep from being hot nay within the very Banks betwixt which that great River runs there boil up hot Srings where those that will go deep enough into the water may commodiously bath themselves And elsewhere speaking of the River Istrogranum in the same County he adds That not only the Banks of it but within the very River it self one may discover hot Springs by removing the Sand at the bottom with ones feet To this I shall add That having heard of a Ditch in the North of England in some regards more strange though less famous then the sulphureous Grotta near Naples whence not only subterraneal steams but those so sulphureous as to be easily Inflamable did constantly and plentifully ascend into the Air I had the curiosity to make inquiry about it of the Minister of the place a very learned Man and conversant in Mines who then happened to be my neighbour and he attested the truth of the relation upon his own knowledge And it was confirm'd to me by a very ingenious Gentleman who went purposely to visit this place and found it true That a lighted Candle or some such actually burning body being held where this Exhalation issued out of the Earth would kindle it and make it actually flame for a good while and if I misremember not as long as one pleas'd And as this place was but few years since taken notice of so there may be probably very many others yet undiscovered that may supply the Air with store of Mineral exhalations proper to generate fiery Meteors and Winds I remember that having lately ask'd an inquisitive Gentleman that is a great searcher after Mines whether he did not observe some meteors near those places where he is most conversant he told me that 't is very usual in some of them to see certain great fires moving in the Air which in those places diggers because of some resemblance real or imaginary are wont to call Draggons And the Russian Emperors Physician you were speaking of inform'd me a while since that he had not long ago observ'd in Winter a River in Muscovy where though the rest of the surface was frozen there was a part of it near a mile long that remain'd uncovered with ice which probably was kept from being generated there by those subterraneous Exhalations since he says he saw them ascend up all the way like the smoak of an Oven And in case the matter of fact delivered by Olaus Magnus be true concerning the strange thaws that sometimes happen with terrible noises in the great Lake Veter those wonderful Phaenomena may not improbably be ascrib'd to the ascent of great store of hot subterraneal steams which suddenly cracking the thick and solid ice in many places at once produce the hideous Noises and the hasty Thaw that he speaks of And this suspicion may be countenanced partly by this circumstance that before these sudden thaws the Lake begins with great noise to boil at the bottom and partly by what is related by a more Authentick writer I mean that learned Traveller the Jesuite Martinius who witnesses that at Peking the royal City of China 't is very usual that after the Rivers and Ponds have continued hard frozen over during the Winter the Thaw is made in one day which since the freezing of the waters as he tells us required many makes it very probable That the sudden thaw is effected as he also inclines to think by subterraneal steams which I may well suppose to be exceeding copious and to diffuse themselves every way to a very great extent since they are able so soon to thaw the Rivers and Ponds of a large Territory and
Claret-wine and if thrust down into either of these liquors they nimbly enough emerged 6. Whether or no Chymical oyls though like expressed oyls they shrink with a moderate degree of Cold would by congelation be like them contracted or like Aqueous liquors expanded we could not satisfie our selves by Experiment because we were unable to advance Cold to a degree capable of bringing such oyls to congelation only we had thoughts to make a trial with oyl of Aniseeds distilled with water in a Limbeck in regard that though it be a very subtile liquor and as Chymists call it an Essential oyl and though in the Summer time and at some other seasons if the weather be warm it will remain fluid yet in the Winter when the Air is cold it will if it be well drawn and genuine easily enough lose its fluidity and therefore we thought it might do well to pour some of it in moderate weather into a conveniently shap'd glass and then to freez it externally by the application of Ice and Salt that we might observe whether upon congelation it would shrink or be expanded And accordingly though we were not provided with any Quantity of this oyl yet in weather that was not sharp we did by the help of some Ice which we procur'd when the season made it a Rarity surround a glass pipe fill'd with fluid oyl of Aniseeds and found though the Pipe were but short yet the inclosed substance when it had lost its fluidity had considerably lost of the height which it reached to before 7. And because the Empyreumatical oyls that are driven out of Retorts by somewhat violent fires seem'd to be of a nature differing enough from those Essential oyls as Artists call them which are drawn in Limbecks by the help of water as well as fire And because we observ'd that some of the firmer oyls may be us'd in Physick in much larger Doses then 't is thought safe to give the latter in Conjecturing from hence that probably Empyreumatical oyls may be less hot and so less indispos'd to Congelation we thought fit to make trial no body else in probability having done it whether the Cold in our Climate could be brought to freez these oyls and whether it would expand or condense them wherefore exposing in conveniently shap'd vessels some good oyl of Guajacum that was diaphanous enough though very highly colour'd to the greatest Cold we could produce we attempted but in vain to deprive it of its fluidity All that we were able to effect being to make it very manifestly shrink Title IX Experiments in Consort Touching the Bubbles from which the Levity of Ice is supposed to proceed 1. SInce the first thing that made the Moderns suspect that water is expanded by freezing is the floating of Ice upon water it will not be 〈◊〉 for confirmation of that Argument to take some notice of the 〈◊〉 of Ice in respect of water This is best observed in great Quantities of Ice for whereas in small fragments or plates the Ice though it 〈◊〉 not to the bottom of the water will oftentimes sink so low in it as scarce to leave any part evidently extant above the surface of the water in vast quantities of Ice that extancy is sometimes so conspicuous that Navigators in their Voyages to Island Greenland and other frozen Regions complain of meeting with lumps or rather floating rocks of Ice as high as their main Masts And if we should meet with Cases wherein we might safely suppose the Ice to be as solid as entire pieces of Ice are wont to be with us and not to be made up of icy fragments cemented together with the interception of considerable Cavities filled with Air it would not be difficult for any that understands Hydrostaticks to give a pretty near guess at the height of the Extant part by the help of what we lately observ'd of the Measures of water's Expansion and by the knowledge of the immersed part which supposing that the Ice were of a prismatical figure and floated in an erected posture would in fresh water amount to about eight or nine times the length of the part of the Prisme superior to the surface of the water 2. But because perhaps the great disparity in the degrees of Cold whereby water is in this and in those gelid Climates turn'd into Ice may breed a difference in the expansion of the frozen water and because some other circumstances may be needful to be taken into consideration about the height of floating Ice above water and these will be more properly taken notice of under the following Title I shall only upon this head of the Levity of Ice subjoyn the ensuing transcript of one of our notes concerning That subject We found that pieces of Ice clear and free for ought the Eye could take notice of from bubbles would not be made to sink in spirit of Wine once distilled from Brandy and it floated likewise in strong spirit of Wine drawn from quick Lime but if the spirit of Wine were well warmed such Ice as I mentioned would sink in it though as it grew cold the same Ice would slowly ascend and sometimes remain for a while as if it were suspended without sensibly rising or falling But all this while the Ice thawed apace in the water whereinto it was dissolved did manifestly seem to run down like a stream through the lighter body of the spirit of Wine the Diversity of the Refractions making this easie to be taken notice of yet common water though heated as hot as I could indure to hold the glass in my hand would not let the fragments of the same parcel of Ice sink into it but in oyl of Turpentine and in thrice Rectifi'd spirit of Wine the Ice would sink like a stone 3. That the levity of Ice in respect of water proceeds from the bubbles that are produc'd in it and make the water when congeal'd take up more room then when fluid has scarce been doubted by any that has consider'd the Texture of Ice as well as taken notice of its levity But if this be the true and only reason we may conjecture that there must be great store of bubbles in Ice extremely minute and undiscern'd by the naked Eye For though in very many parcels of Ice the bubbles are as well conspicuous as numerous insomuch that they render the Ice whitish and opacous yet we have observed that other pieces would swim which yet were of an almost crystalline clearness And therefore we thought fit to look upon some clear pieces of Ice in a Microscope and we shall subjoyn the Event because that when we beheld some of this ice in one of our Microscopes which has been counted by several of the curious as good a Magnifier as perhaps any is in the world we could not discover such store of bubbles as it seemed there should appear upon the supposition that the adequate cause of the levity and expansion of frozen water is
expansion wrs considerable since the water rose three inches and a half in the stem though the whole water in the Egg and stem too weighed but two ounces and a half 〈◊〉 the vessel had not been unluckily cracked we should have frozen the water once more and then sealing up the glass Hermetically and suffering the ice leisurely to thaw should have inverted it and broken it under water and have proceeded with it as we had done with some other glasses in the formerly mentioned Experiments 9. A little glass Cylinder open only at one end of a convenient length was thrust into a deep and wide mouth'd-glass about half filled with a mixture of Ice and salt but the Cylinder was neither so quite filled that the water should run over nor yet far short of being so that for all the opacous mixture of Ice and Salt we might guess at the freezing of that part of the water that we could not see by the changes appearing in the other Then conveying all into a Receiver that we had in readiness beforehand we quickly pumped out the Air upon which there came both from the upper lower parts of the water great store of Bubbles to the top where most of them brake into the Receiver having found upon trials purposely made that the Engine had continued stanch all the while and perceiving by the intumescence of the superior parts of the water that the other were frozen we let in the external Air and having removed the Receiver and taken out the mixture before the Ice was half melted we found the water as high as the mixture reached to be turn'd into ice which besides some large and conspicuous bubbles had small ones enough to render it opacous and upon the account of this expansion it was that the water did in the free Air continue a good deal higher then the mark it was but level with when the Cylinder was exposed to freez 10. The other way we employ'd to examine what was contained in icy bubbles and which seemed clearly enough to manifest that they are very far from being filled with true and springy Air is intimated in the last clause of the foregoing narrative but will be best understood by the annexed Experiments transcribed just as I find them registred in my Collections and though they be prolix and contain some few Particulars that make not directly for the purpose I alledge them for yet I think not fit to dismember or to epitomize them or otherwise to alter any thing in them partly that the inference I make from them may be the less mistrusted partly because the way of Experimenting being altogether new will be best apprehended by the subjoyned Examples and partly too because those Particulars that relate not directly to the occasion of our mentioning these trials may be useful to illustrate or confirm some thing that is already delivered or is hereafter to be delivered in the present History of Cold. 11. We took this day a glass of the form of an Egg but of double the capacity out of whose obtuse end rose up a long Cylindrical neck capable to receive the end of my little finger and no more this being fill'd with common water till the liquor reached a pretty way within the pipe and the surface of the water being carefully marked on the outside was placed in a vessel wherein ice very grosly beaten was mingled with a convenient Proportion of salt according to our way of Glaciation the Mixture not reaching up to the mark by above an inch The Experiment afforded us these Particulars I. A heedful Eye did not perceive the water sensibly to subside before it began to freez II. The water began to swell and some parts of it next the side or bottom of the glass to freez within a quarter of an hour III. The ascent of the water in the pipe increased so fast that within an hour from the time the glass was put in it did rise 4. inches and 2 9 above the mark afterwards the swelling connutied so that we took it out though a good part of the water remain'd unfrozen it had reach'd five inches and somewhat more then a half above the first Mark. IV. The ice and salt being purposely kept always beneath the surface of the water the lower parts of the water were frozen and never the upper surface V. During all this great Elevation of the water there appeared no bubbles worth taking notice of in the unfrozen parts of the liquor but the ice was very full of them divers of which toward the latter end of the Experiment were very large Bubbles but not all of them round some being about the bigness of hail shot some small like Mustard seed and others again not much inferior to little pease VI. Having taken out the glass when the water was at the highest mark we did upon a certain design pour in as much sallet Oyl as swam about two inches above it and then the glass was nimbly at the flame of a Lamp seal'd up during which time the included water subsided a little but the glass being again put into the ice and salt the Cold quickly restored the water to its former height and there remained about an inch and a half of the seal'd glass unpossessed by the two contain'd liquors VII Then with a good pair of scales we weigh'd the glass-Egg first in the Air and then in the water the better to discern whether any shrinking of the glass interven'd in the case where it hung freely and was left hanging in its Equilibrium with its opposite weight VIII Whilest it thus hung upon the thawing of the ice many bubbles great and small ascended the great ones with a wrigling motion and vanish'd at the top IX As the ice thaw'd the water and oyl descended till the whole ice was return'd to water at which time we observ'd these two remarkable things the one That the Equilibrium remain'd the same the other which was more considerable that the water was subsided again as low as the first mark with which it was level before it began to swell without falling beneath it notwithstanding the recess of such a multitude of Bubbles divers of which were very large X. The glass being inverted the seal'd end which was drawn slender was gently broken under water of which some being impell'd in did sensibly reduce the Air at the opposite end into a narrower room and as one of the spectators observ'd into a much narrower which is consonant enough to reason XI The glass being again inverted and held till it was setled we found that the water drawn in together with the water it found there and the oyl possess'd the same places as appeared by the marks in the Cavity of the Receiver that they did when it was seal'd up XII And lastly having thrown out the oyl and employing where need was a little water of the same kind we had made use of all this while
we found the glass fill'd to the highest mark to weigh 4374. grains when it was fill'd but to the lowest mark 4152. grains and when quite empty'd 1032. So that the water contain'd betwixt the highest and lowest mark and rais'd by the Glaciation was about a fifteenth part of the water set to freez and probably would have amounted to much more if the water had been all frozen 12. A large glass-Egg being taken with a proportionably big stem we poured water into it till it reached about an inch above the bottom of the stem and fastning a mark there we exposed it all night to freez in snow and salt which was so placed as not to reach so high as the bottom of the stem the next day about ten of the clock we found the water risen in the stem about 15. inches above the mark the whole Cylinder of water being fluid by reason of the snows not reaching to it Then upon a design to be elsewhere mentioned we seal'd up the glass by a very slender pipe that had been before purposely drawn out to a pretty distance from the body of the Cylinder that the glass might be seal'd in a trice before the flame of a Candle could sensibly rarifie the Air and after a while we broke off the Apex of this slender pipe in prosecution of our former Design Then suffering the water to swell freely within seven or eight hours it reach'd the very top of the glass a drop or two running over at the slender Orifice thereof so that in all the water ascended about 19. inches above the first mark then we tried by the flame of a candle to seal the glass but by reason of the Rarefaction of some of the water by the Heat into vapours by which some of the other water was from time to time spurted against the flame of the Candle we found it troublesome enough to seal it up the vessel being removed into a warm place till next morning and all the ice in the belly of it for the water in the stem continued fluid being thawed the water subsided not only to its first mark but a little beneath it by reason of that which was thrown out upon occasion of the sealing of the glass but when we came to invert this after the manner above mention'd into a vessel of water to see how much of the space deserted by the thaw'd Ice was fill'd with Air and how much was fill'd with a subtiler substance or empty just then a mischance frustrated our Expectation 13. An Egg about the same bigness with the former was placed to freez in beaten ice and salt and in less then a quarter of an hour it was risen near an inch above the Mark where the surface of the water was at the first and the water in the ball and the joyning of the neck was frozen into Laminae After an hour and a quarter those Laminae that before appeared in the beginning of the neck now disappear'd but the ball seem'd frozen into a white ice and the water in the neck was risen above the first mark four inches and a half There now appear'd abundance of small bubbles continually ascending through the neck which so continu'd all the time after till it was quite thaw'd and the white ice appear'd full of bubbles The Experiment being further pursu'd the water ascended higher and higher till it had reach'd about eight inches above the first mark Then the top of the pipe being with a Lamp drawn out into a very slender Cylinder for the conveniency of sealing up the glass was again put into the ice that the Air heated by the Lamp might cool upon which the water continued swelling till it began to run over at the orifice of the slender pipe which being held by in the flame of a candle was in a trice seal'd up so that the whole glass now appear'd full of water bating an inconsiderable Quantity of rarifi'd Air not amounting to the bigness of half a small Pea that remain'd contiguous to the seal'd part the Egg being brought into a warm room was kept there all night and a good part of the next morning before the ice was quite thaw'd which when it was the water was found subsided to the first mark and which being done the glass was inverted and the seal'd end immers'd a good way under water where being broken the external Air impell'd the water in the Bason into the Cavity of the pipe insomuch that when we took it out which we did as soon as we thought nomore water was impell'd up reinverting the glass we found that the admitted water reach'd seven inches above the first mark and left an inch and a half of the stem before it began to be wire-drawn besides as much of the slender part of the stem as by guess amounted to a quarter of an inch or more so that it seem'd that the Bubbles which made the water swell and appear'd in the 〈◊〉 amounted to an inch and three quarters of Air which consequently seem'd to be for the most part generated by this operation and to seven inches either of a vacuum or some 〈◊〉 substance which by its having no spring to resist the Pressure of the outward Air appear'd not to be Air We could not exactly measure the Quantity of water we had in all and the proportion of it betwixt the marks 〈◊〉 having left the glass in the window to try whether time or Cold would make the admitted water shrink which we did not find it to do the weather was so sharp that beginning as we concluded to 〈◊〉 the water in the stem the increasing ice burst out the belly of the glass into many pieces Another time 14. A seal'd glass being broken under water there was impell'd into the Cylinder ten inches and a little above a half And the mark it should have risen to was eleven inches and a quarter above the first and lowest mark Another time 15. In the same Bolthead wherein the greatest condensation of the Air was tri'd the water was by the Cold made to swell very near a foot above the mark it rested at when it began to freez then the glass being 〈◊〉 up the contain'd water was removed and suffered leisurely to thaw and upon the Dissolution of the ice the water fell back to the former mark lastly the glass being inverted the Apex was broken off under water and the water in the stem was by the outward Air pressing upon the water in the Bason with some Impetus and noise driven up into the Cavity of the glass and the glass being seasonably and warily remov'd from the Bason we found there had been impell'd up of the water in the Bason a little more then eleven inches so that there seem'd to be near ⅞ of an inch of Air generated or separated by the former operation Another time 16. In the same glass we made the water to swell about ten inches and
Air to be condens'd at the time of the sealing was accounting by Estimation for the slender pipe newly taken notice of almost 9 â…ž inches This space we observed the ascending water as the ice increas'd below to invade by degrees for we watch'd it and measur'd it from time to time so much till at length the water reach'd to 8. inches and â…ž almost above the station which we had carefully mark'd with a Diamond in which we found it when the glass was seal'd up leaving but about an inch of Air at the top so that of the whole space before possess'd by the Air the water had intruded into near nine parts of ten then being partly apprehensive the glass would hold no longer but have its upper part blown off as it happened to us a little before with another vessel and partly being desirous to try that which follows we leisurely inverted the glass that the Air might get up to the ice for all the water in the stem had been purposely kept unfrozen and having provided a Jar to receive the water that should be thrown out we broke the slender pipe which we had seal'd up and immediately as we expected the compressed Air with violence and noise blew out of the stem into the Jar about ten inches of water which was somewhat more between half an inch and a whole inch by reason of the Impetus of the self expanding Air then the space possess'd by the Air before it began to be compress'd And besides this such a strange multitude of Bubbles that were formerly repress'd did now get liberty to ascend from the lower parts of the glass to the top of the remaining water that it somewhat emulated that which happens to botled Beer upon the taking out of the Cork N. B. when the Air was compressed beyond seven inches we observ'd divers times that the inside of the glass possess'd by the Air and nearest to the water was round about to a pretty height full of very little drops like a small dew but when we came to break the glass we took noe such notice whether the rising water had lick'd them up or their concourse made them run down into it or for some other reason we determine not Another 5. We took a single vial filled with water about half an inch above the lower part of the neck and leaving about two inches of Air in the remaining part of the neck which was drawn out into a slender pipe like that of the glass last mentioned we seal'd it up the Air being first well cool'd and exposing it to freez we observ'd a while after that it had by guess condens'd the Air into lesser room A while after being in another Chamber we heard a considerable noise and imagining what it was we went directly to the glass whose upper part consisting of about an inch of the neck besides the slender pipe we found had been blown off from the table upon the ground the body and part of the neck remaining in the snow but this glass was of a mettal that uses to be more brittle then white glass Another 6. A round white glass almost fill'd with water was seal'd up with care to avoid heating the included Air which amounted to a Cylinder of about two inches and â…ž after a while the water swell'd and compressed the Air almost two inches that is full two thirds and then as we conjectur'd because the snow reaching too high froze it in the neck we found the glass crack'd in many places of the Ball and the top thrown off at some little distance from it Another 7. A large single vial seal'd in whose neck the Air was not condens'd to half its former room just as we were going to break it under water to observe the sally of the compress'd Air suddenly blew off with a good noise and threw from the table almost the whole neck of the Vial in one intire piece which is near four inches long and at the Basis above an inch broad 8. A glass about the bigness of a Turkey Egg and of an oval form with a Neck almost Cylindrical but somewhat wider at the lower then the upper part was fill'd with water till there was left in the neck four inches and a half whereof the last quarter of an inch and a little more was much narrower then the rest being drawn into a conical shape that it might be easily seal'd at the Apex along this Cylinder from the surface of the water to the top of the glass was pasted a list of Paper divided into inches and quarters and then the glass being carefully and expeditiously seal'd up by the flame of a candle we observ'd that by holding the glass a while in a warm hand and a room where there was a good fire the water was swell'd up near a quarter of an inch but placing the glass amongst solid pieces of ice mixt with salt the water quickly began to subside upon the Infrigidation and a while after beginning to freez it began to swell and by degrees compress'd the Air till it had crowded it into less then a 17. part by what seem'd indisputable for by estimate it seem'd to some to be crowded into less then a 20. part is not a much lesser part of the room it formerly possess'd which difference of Estimates notwithstanding the divided Paper proceeded from the change of the figure of the upper end of the glass from the Cylindrical and to shew that there was no leak at the place where the glass was seal'd besides that by prying diligently we could discern none besides this I say when the pressure of the thus crowded Air grew too strong for the resistence of the glass it burst with a noise that made us come to it from several places of the house the vessel broke not in the Cylindrical part as I may so speak but in the oval the whole pipe with the seal'd end remaining entire the ice appear'd full enough of Bubbles which made it white and opacous and the water that had ascended into the neck upon the breaking was all driven out of it Thus far our Collections but because we had in another glass where the operation was sooner dispatch'd an opportunity of watching observing somewhat more exactly we will add 9. That the last and possibly the best Experiment we had of compressing Air by freezing was made in a short and strong glass Egg whose ball was very great in proportion to the stem that the expanding of the water might have the more forcible operation This vessel being exactly seal'd and having a divided list of paper pasted along the stem was set to freez with snow or ice and salt and the contain'd water did quickly begin to crowd the Air into a lesser room and for a good while ascended very fast till at length it having thrust the Air into so small a part of the Cavity of the pipe that we vehemently suspected there might
examine this having taken a piece of Ice we did not find upon trials that I partly made my self and partly caus'd in my presence to be made by others that if a mans Eyes were close shut he could certainly discern the Approach of a moderately siz'd piece of Ice though held never so near his fingers ends Nay which is more considerable having had the curiosity to make the Trial with one of those very sensible Thermoscopes I have formerly mention'd wherein a pendulous drop of liquor plays up and down in a slender pipe I found that by holding it very near to little Masses of snow somewhat compacted too the movable drop did not betray any manifest operation of so cold a neighbouring Body but if the glass were made to touch the snow the effect would then be notable by the hasty descent of the pendulous drop or its motion towards the obtuse part of the Instrument in case that were not perpendicularly but laterally appli'd to the snowy Lumps But this languidness of operation may perhaps proceed in great part from the smallness of the Pieces of Ice that were imploy'd For hearing of a Merchant that had made divers Observations about Cold in Greenland I desir'd by the mediation of a very learned Friend to be inform'd whether or no in the night they could perceive those vast heaps or rather mountains of ice that are wont to float up and down in that Sea by any new and manifest accession of Cold and was inform'd by way of Answer to that Question that being at Sea they could know the approach of Ice as well by the increase of Cold as by the glaring light which the Air seem'd to receive from the neighbouring Ice 3. But that which makes me suspect that there may in this account be some mistake is that I have not yet met with any like observation in any of the voyages into gelid Climates that I have had occasion to peruse though in some of them the Navigators frequently mention their having met with vast rands as some call them and Islands of mountainous ice in the night And 't is as I remember the complaint of one or two if not more of them that the Ship lay close by such vast pieces of ice without their being aware of it by reason of the fogs By which it seems that there was no sensible Cold diffused to any considerable distance whereby they might be advertised of the unwelcome neighbourhood even of so much ice But possibly the approach of far smaller masses of ice would have been sensible to them in such a Climate as ours where the organs would not have been indisposed to feel by a long accustomance of any thing near so intense a degree of Cold as that which then reigned in those Northern Seas 4. Whilest we were considering the Difference betwixt the operations of even the Coldest Bodies at the very nearest Distance and upon immediate Contact we thought it an Experiment not altogether unworthy to be tri'd whether though ice and snow alone that is unassisted by salts would not in some of our formerly mention'd Experiments freez water through the thickness even of a thin glass they may not yet do it when the water is immediately contiguous to them And I remember that we took a conveniently shap'd Glass and having frozen the contained water for some hours from the bottom upwards till the ice was grown to be of a considerable thickness we mark'd what part of the glass was possess'd by the unfrozen water and then removing the vessel to a little Distance from the snow and salt it stood in before we let it 〈◊〉 there to try whether the ice would freez any part of the contiguous and incumbent water but some intervening accidents hindred us from being able to derive any great satisfaction one way or other from our trial 5. Wherefore we shall add by way of Compensation that the diligent Olearius relates that at Ispahan the Capital City of Persia though it be seated in a very hot Climate and though it seldom freez there above a finger thick and the ice melt presently at Sun-rising yet the Inhabitants have Conservatories which they furnish with solid pieces of ice of a good thickness only by pouring at night great store of water at convenient intervals of time upon a shelving floor of Free-stone or Marble whereon as the water runs over it the most dispos'd of its parts are in their passage arrested and frozen by the contiguous ice which by this means says my learned Author may be brought in two or three successive nights to a very considerable thickness 6. We several times gave order to have this Experiment tried in England but partly through the negligence of those we imploy'd and partly upon the score of intervening circumstances our expectation was but ill answered And in this case I mention intervening circumstances because having caus'd a servant to pump in the night upon a not very thin plate of ice that was laid shelving upon a Board and another flat piece of Ice being about the same time laid under a place where water derived from a neighbouring spring is wont continually to drop he brought me word that not only in this last nam'd place the ice melted away but that under the pump instead of increasing in thickness by the waters running over it it was thereby rather dissolv'd At which somewhat wondring I went in the morning my self to the pump and causing a good flake of ice to be in a convenient posture plac'd under it I observed the water as it came out of the pump and was falling on the ice to smoak as if the depth of the Well had made the water though very Cold to the touch somewhat warm in comparison of the ice and thereby fitter to resolve then to increase it which inconvenience may be prevented by suffering the water of deep Springs and Wells to stand to cool in the Air before it be put to the Ice and this though the neighbouring Air were as I found by manifest proofs so cold that I was not tempted to impute the unsuccesfulness of the Experiment rather to its want of a sufficient coldness then the water's So that till I have an opportunity of making a further Trial I cannot 〈◊〉 more to the Persian way of augmenting ice But to proceed our having met with but an unsatisfactory Account of this Experiment which we were the more troubled at because this seem'd a promising way of trying that which otherwise is not so easily reduc'd to Experiment for the Temperature of the Air must be seriously consider'd in assigning the Cause of divers trials that may be made for the resolving of the same Question For to omit other Examples here in England we find that water poured on snow is wont to hasten the Dissolution of it and not to be congeal'd by it whereas having inquir'd of an Ingenious Person that liv'd a good while among the Russians
hours having been diverted by some occasions from taking it sooner out we found as we had conjectured that notwithstanding that the oyl of Turpentine continued perfectly fluid as before yet the Bubble totally immersed in this heating Chymical oyl was frozen throughout not excepting that which was harboured in the little Neck or Stalk and when I came to lift it out of the liquor the glass being crack'd as we supposed by the Cold the string brought up a little part of that which was nearest to it the rest in the form above mentioned staying behind and subsiding And that which was remarkable in this piece of Ice was that when we had taken it out it appeared cleft very deep from the outside almost to the centre according to a line drawn from the slenderest part of it almost as if one should with a knife cut a Pear in two from the stalk downwards according to its whole length And these two pieces were easily enough separable and to adde that circumstance for trial sake we left them divided in the same liquor and vessel with some thawing Ice and Salt about them for 14. or 15. hours without finding them any thing near so much wasted or resolved into water as most would have expected Whilest the above mentioned Bubble was exposed to be frozen we likewise placed by it in another vessel a Glass-Egg whose Ball and a little part of its stem we had fill'd with some of the very same parcel of oyl of Turpentine and placing about the sides of this Egg some ice and salt we observed as we expected that the liquor was after a little while made by the Cold to subside about half an inch so that 't is worth some Philosophers considering why if according to the lately mention'd Atomical doctrine Cold be made by the introduction of swarms of real and extended though Atomical Bodies they should pervade the oyl and contract it without freezing it but freez the water without contracting it but expending it rather 9. A small bubble of the bigness of a very little Nutmeg fill'd with water and Hermetically seal'd up was by a cork and a string suspended in spirit of Wine so as to be surrounded therewith and being exposed to the Air the same night in the stopt glass was the next morning found altogether frozen though the spirit of Wine it self were not at all so But another bubble by the help of a string Cork and piece of Lead carefully suspended in a strong solution of Sea-salt and exposed at the same time in a like vessel with the former when they both came to be look'd upon appear'd to be no more frozen then the brine it self which was not so at all 10. A glass Bubble of the bigness of a small Nutmeg fill'd with water and Hermetically seal'd being immersed by a weight of Lead fastned to it beneath the surface of a very salt Brine but yet not so as to reach the bottom of the liquor or glass was exposed all night to freez in weather that was extraordinarily cold but neither the imprison'd water nor the other appeared to be at all frozen The like Experiment we repeated another frosty night but without freezing either of the liquors But to show the usefulness of repeating Experiments about Cold if there be opportunity and especially in such cases where the degree or some other circumstance may much vary the event we will add that having exposed a Bubble like that newly mention'd and immers'd in spirit of Wine we found the next morning the water in the bubble turn'd into ice and having likewise exposed such a bubble immers'd in very strong Brine to be frozen by a mixture of ice and salt within about two hours after we found the bubble broken as we suppos'd upon the Expansion of the water upon its growing Ice And we also found the upper part of the bubble with the Ice sticking to it and the other part of the glass was crack'd with lines running from a point almost like the Pole and Meridian in a Globe whence we concluded the glass to have been as 't is probable burst asunder upon the Expansion of the fresh water into ice and that the Reason why there remain'd but a comparatively little parcel of ice was probably that the salt water getting in at those crannies or chinks dissolved as much of the new made ice as in a little while it could easily reach Besides 11. We fill'd a glass bubble with fair water and having Hermetically seal'd it we suspended it by a string fastned to the cork in the cavity of a wide mouth'd glass well stopt so that the bubble was every way at a good distance from the sides bottom and top of the glass This we did to try whether a sufficient degree of Cold at that distance would be freely transmitted through the glass without the intervention of a visible liquor and accordingly we found the suspended Bubble crack'd by the ice that fill'd it Title XV. Experiments and Observations touching Ice 1. A Great part of our present History being imploy'd about delivering the Phaenomena of Congelation it is not to be expected that in this Section where we treat of Ice as a distinct part of our Theme we should deliver all those particulars that have occurr'd to us wherein ice is concern'd And therefore we shall restrain our selves to the mention of those that belong to ice considered as it consists of intire and distinct Portions of congeled water Aud though we shall deliver some few Experiments of our own such as we had any opportunity to make yet much the greater part of this Section will fitly enough be taken up by Collections out of Travellers and Navigators into those Colder Regions that afford much considerabler or at least much stranger Observations concerning ice then are to be met with in so temperate a Climate as ours And what we have to deliver in this Section will naturally be divided into two parts the one consisting of our own Experiments 〈◊〉 the other containing some Passages that we have selected out of Voyages or that have been afforded us by the Relations of credible Travellers And of these two sorts of Observables that which has been first mention'd shall be first treated of 2. Some that have been in the East Indies inform us that in some parts of those Countries they were looked upon as great Liars for affirming that in Europe the fluid body of water was often without any artifice or endeavour of Man turned in a few hours into a solid and compact Body such as Ice And certainly if custom did not take away the strangness of it it would to us also appear very wonderful that so great a change of Texture should be so easily and inartificially produced But how solid the Body of ice is or rather how strong is the mutual adhesion of its parts has not yet that we know of been attempted by Experiments to be reduced to some kind of
I shall content my self to make use of this obvious 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 of Cold that in Rivers Ponds and other receptacles of water the congelation begins at the Top where the liquor is expos'd to the immediate contact of the Air which sufficiently argues that the Air is colder then the Water since it is able not only sensibly to refrigerate it but to deprive it of its fluidity and congeal it into Ice whereas if the water it self were the primum frigidum either it ought to be at least as to the major part of it always congeal'd or we may justly demand a reason why when it does freez the glaciation should not begin in the middle or at the bottom as soon as at the Top if not sooner And our Arguments against the precedency of the water in point of coldness may be strengthen'd by this That frosts are wont to be hardest when the Air is very clear and freest from Aqueous vapors whereas in rainy weather wherein such vapors most abound the cold is wont to be far more remiss To which we may add what we lately deliver'd from the observation of Navigators that even in the frigid Zone the main Sea where yet the water is in the greatest mass and so most likely as well as advantag'd to disclose its nature never freezes though the Straits and Bays and Gulphs be frozen over which argues that the greatest degrees of Cold are rather to be assign'd to the Air or to the Earth then to the Water which by the practise formerly mention'd of the Masters of the French Salt Marshes appears to be when it is of a considerable depth fitter to preserve Bodies from congelation then to congeal them which instance I the rather repeat because it seems to argue that the water is not so much as dispos'd to receive any very intense degree of cold at a remote distance from the Air for though Navigators tell us of exceeding thick pieces of Ice yet as we have already elsewhere noted we are not bound to believe that the congealing cold has pierced any thing near so much as that thickness amounts to from the superficies of the Sea directly downwards for though it were no great matter if it did in comparison of that depth of the Sea which though the water be naturally cold the sharpest Air is unable to congeal yet we have elsewhere proved that those thick masses of Ice are not solid and intire pieces but rather heaps of many 〈◊〉 and other fragments of Ice which running upon one another or sliding under one another are by the congelation of the intercepted water and perchance half thaw'd snow as it were cemented together into mis-shapen and unweildy masses which conjecture agrees very well with that observation of the Ingenious Captain James which he delivers in these words It seldom rains after the middle of September but snows and that snow will not melt on the lands nor sands At low water when it snows which it doth very often the sands are all covered over with it which the half tide carries 〈◊〉 ously twice in twenty four hours into the great Bay which is the common Rendezvous of it Every low water are the sands left clear to gather more to the increase of it Thus doth it dayly gather in this manner till the latter end of Octob. and by that time hath it brought the Sea to that coldness that as it snows the snow will lye upon the water in flakes without changing its colour but with the wind is wrought together and as the Winter goes forward it begins to freez on the surface of it two or three inches or more in one night which being carried with the half tide meets with some obstacle as it soon doth and then it crumples and so runs upon it self that in few hours it will be five or six foot thick the half tide still flowing carries it so fast away that by December it is grown to an infinite multiplication of Ice Thus far this Navigator to which I shall add another passage out of one of his Countreymen Mr. Hudson famous for the Northern Discoveries that bare his name by which added to what has been elsewhere deliver'd to the same purpose we may be invited to believe that the vast Hills and Islands of Ice that are to be met with about the Straits of Weigats and elsewhere are not generated of the Sea it self It s no marvel says he that there is so much Ice in the Sea towards the Pole so many Sounds and Rivers being in the Lands of Nova Zembla and Newland to ingender it besides the coasts of Pechora Russia and Greenland with Lappia as by proof I find by my Travel in these parts 15. But for all this I think not fit as does the Ingenious Gassendus and some others to make the water indifferent as to heat and cold For as I formerly noted concerning the Earth so I must now represent touching the water that setting aside the 〈◊〉 of the Sun which is but adventitious where it does operate and 〈◊〉 〈◊〉 many vast portions of that Element which it 〈◊〉 not 〈◊〉 reach the insensible parts of water are much less agitated then those of our Sensories temperately dispos'd and consequently may in regard of us be judg'd cold For though water being a Liquor I readily allow it a various Motion of its component Corpuscles that being requisite to make a Body fluid yet such an agitation which is sufficient for fluidity may be and often is far more remiss then that of the spirits Blood and other liquors of so hot a Sanguineous animal as Man as we see that Urine though after it has been long omitted it continues a fluid Body yet its parts are far less agitated then they were when it came hot and reeking out of the Bladder 16. And upon this occasion I shall add what by inquiry I have learned that except the parts somewhat near the superficies of the water which the heat of the Sun or the warmth of the neighbouring lower Region of the Air may give some warmth to the whole Body of the Sea is very cold for being very well acquainted with one that for some time got a livelihood by going down into the Bottom of the Sea to fetch up what could be recovered out of shipwrackt vessels I purposely inquired of him what cold he felt under water and he more then once told me that though near the Top of the water the cold were very moderate yet when he was necessitated to descend a great depth he found it so great that he could not very long support it and particularly he told me that having occasion to descend about twelve or fourteen fathom deep which is nothing in comparison of the depth of many Seas to fasten ropes to the Ordinance of a great ship that was some years since cast away near the coast of one of the Northern Countries though the Engine that was let down
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-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
but such as eat flesh as Bears and Foxes c. although Nova Zembla lyeth 4 5 and 6. degrees more Southerly from the Pole then the other land aforesaid And to this purpose I remember what is related by the learned Josephus Acosta concerning the Heats and Colds in the Torrid Zone and elsewhere When I pass'd says he to the Indies I will tell what chanc'd unto me having read what Poets and Philosophers write of the burning Zone I perswaded myself that coming to the Aequinoctial I should not indure the violent heat but it fell out otherwise for when I pass'd which was when the 〈◊〉 was there for Zenith being entered into Aries in the moneth of March I felt so great a cold as I was forc'd to go into the Sun to warm me what could I else do then but laugh at Aristotles Meteors and his Philosophy seeing that in that place and at that season when as all should be scorch'd with heat according to his rules 〈◊〉 and all my companions were a cold in truth there is no Region in the world more pleasant and temperate then under the Equinoctial although it be not in all parts of an equal temperature but have great diversities The burning Zone in some parts is very temperate as in Quitto and on the plains of Peru in some parts very cold as at Potosi and in some veryhot as in Ethiopia Brasile and the Molucques And within two Chapters after he discourses more largely of some of these Particulars And again Chapter the 12. You may continually says he see upon the tops of these mountains snow hail and frozen waters and the cold so bitter as the grass is all wither'd so as the men and beasts which pass that way are benumm'd with cold This as I have said is in the burning Zone and it happens most commonly when they have the Sun for Zenith These Testimonies of a learned man that writes upon his own knowledge I thought it worth producing to make it probable that as in several Countries the heat does not always answer to the nearness of places to the Line so in Northern Regions the cold may not always be proportionate to their vicinity to the Pole In Mr. Hudsons second voyage written by himself he mentions that above 71. degrees though they were much pester'd with ice about the end of June that day when this hapned was calm clear and hot weather adding of the next day also that it was calm hot and fair weather And Acosta tells us that we see these differences not only on the land but also on the Sea there are some Seas where they feel great heat as the report of that of Mazambigus and Ormus in the east and of the Sea of Panama in the west There are other Seas in the same degree of height very cold as that of Peru in the which we were a cold when we first sail'd it which was in March when the Sun was directly over us In truth on this continent 〈◊〉 the Land and Sea are of one sort we cannot imagine any other cause of this so great a 〈◊〉 but the quality of the wind that 〈◊〉 refresh them But to multiply no more instances we shall conclude with this one That Charleton Island where Captain James winter'd and of which we so often have occasion to make mention in our History though it seems by the effects to be a colder Region then even the Countrey about Musco and perhaps as cold as Nova Zembla it self yet Captain James who had several times occasion to take the latitude of it and assignes it the same Elevation and consequently the same Distance from the Pole with Cambridge whose latitude he reckons to be 51. degrees besides minutes and whose air is very well known to be very temperate And it is remarkable that though this place whose latitude is short of 52. degrees was found uninhabitable by reason of the cold yet not only in Mr. Hudsons Voyage the writers admonish the Readers to take notice That although they ran along near the shore they found no great cold which made them think that if they had been on shore the place is temperate And yet in this place they reckon themselves to have reach'd the 78. degree of latitude And our recenter Navigations inform us that several parts of Greenland to which this newly mentioned coast belong'd are well enough inhabited And one of our English Navigators assures us that the true height of Pustozera in Russia is no less then 68. degrees and a half if not more and yet that is a town not only well inhabited but of great trade but in Hudsons voyage I find what is more strange That under the 81. degree of latitude beyond which they discovered land very far off but beyond which none is thought to have actually sail'd toward the Pole they found it during the whole day clear weather with little wind and reasonable warm And beyond 80. degrees they not only found a stream or two of fresh water but found it hot on the shore and drank water to cool their thirst which they also commended II. The next observable I am to propose about the coldness of the Air is this That the degrees both of Heat and Cold in the air may be much greater in the same climate and the same place at several seasons of the year or even at several times of the same day then most men would believe For the proof of this Proposition we shall subjoyn two sorts of Testimonies of Travellers and Navigators the former shewing that in Countries where it is very cold in Winter it may 〈◊〉 be hot in Summer and the latter manifesting that even on the same day as well as in the same place the heat and cold that succeed one another may be one of them sensible though the other were extreme or may perhaps be both of them considerable To make this good we shall produce the following Testimonies 1. Dr. Giles Fletcher English Ambassador to the Muscovian Emperor in his Treatise of Russia and the adjoyning Regions has this memorable passage to our present purpose The whole Countrey says he differeth very much from it self by reason of the year so that a man would 〈◊〉 to see the great alteration and difference betwixt the Winters and Summers in Russia The whole Countrey in the Winter lyeth under snow which falleth continually and is sometime of a yard or two thick but greater towards the North the Rivers and other waters are all frozen up a yard or more thick how swift or broad soever they be and this continueth commonly for five moneths to wit from the beginning of November till towards the end of March what time the snow beginneth to melt so that it would breed a frost in a man to look abroad at that time and see the Winters face of that Countrey And a little after he adds And yet in the Summer time
may be very warrantably question'd For 't is evident in waters we expose to freez in large vessels that the congelations begin at the surface where the liquor is 〈◊〉 to the Air and thence as the cold continues to prevail the ice increases and thickens downwards and therefore we see that Frogs retire themselves in frosty weather to the bottom of ditches whence I have had many of them taken out very brisk and vigorous from under the thick ice that cover'd the water And I have been informed by an observing person that at least in some places 't is usual in Winter for shoals of Fishes to retire to those depths of the Sea if not of Rivers also where they are not to be found in Summer Besides if Rivers were frozen at the 〈◊〉 we must very frequently meet in the emergent pieces of ice the shapes of those irregular Cavities and Protuberances that are often to be found in the uneven soils over which Rivers take their course whereas generally those emergent pieces of ice are flat as those flakes that are generated on the surface of the water Moreover if even deep rivers freez first at the bottom why should not very many Springs and Wells 〈◊〉 first at the bottom too the contrary of which nevertheless is obvious to be observ'd In confirmation of all which we may make use of what we formerly noted in the Section of the Primum Frigidum about the 〈◊〉 of the Masters of the French Salt-works who by overflowing the Banks and Causeways all the winter keep them from being spoil'd by the srost which could not be done if the waters they stand under froze as well at the bottom as at the Top. But I find that that which deceives our Water-men is that they often observe flakes of ice to ascend from the bottom of Rivers to the Top and indeed it often happens that after the hard frost has continued a while these emergent pieces of ice do very much contribute to the freezing over of Rivers For coming in some of the narrower parts of them to be stopp'd by the superficial ice that reaches on each side of the River a good way from the Banks towards the middle those flat icy bodies are easily cemented by the violence of the cold and by the help of the contiguous water to one another and by degrees straitning and at length choaking up the passage they give a stop to the other flakes of ice that either emerging from the bottom or loosened from the banks of the River or carried down the stream towards them and these being also by the same Cold cemented to the rest the River is at length quite frozen over And the reason why so many flakes of ice come from the bottom of the River seems to be that after the water has been frozen all along near the banks either the warmth of the Sun by day or some of those many casualties that may perform such a thing does by thawing the ground or otherwise loosen many pieces of that ice together with the earth stones c. that they adher'd to from the more stable parts of the banks and these heavy bodies do by their weight carry down with them the ice they are fastned to but then the water at the bottom of the river being warm in comparison of the Air in frosty weather since that even common water is so we have manifested by experience where we show how much sooner ice will be dissolv'd in water then thaw'd in Air the dispers'd ice is by degrees so wrought upon that those parts by which it held to the stones earth or other heavy bodies being resolv'd the remaining ice being much lighter bulk for bulk then water gets loose and straightway emerges and may perhaps carry up with it divers stones and clods of earth that may yet happen to stick to it or be inclos'd in it the sight of which perswades the Water-man that the flakes of ice were generated at the bottom of the river whereas a large piece of ice may carry up and support bodies of that kind of a great 〈◊〉 in case the ice it self be proportionably great so that the Aggregate of the ice and heavy bodies 〈◊〉 not the weight of an equal bulk of water On which occasion I remember that Captain James Hall in a voyage extant in Purchas relates that upon a large piece of ice in the Sea they found a great stone which they judg'd to be three hundred pound weight But of the Tradition of the Water-men we shall say no more then that this hath been discours'd but upon no great information though the best we could procure so that for further satisfaction it were to be desir'd that either by sending down a Diver or by letting down some instrument fit to feel if I may so speak the bottom of Rivers with and to try whether ice if it met with any be loose from or uniformly coherent to the ground and also bring up parcels of whatever stuff it meets with there the matter were by Competent Experiments put out of doubt We took a seal'd Weather-glass furnish'd with spirit of Wine and though not above 10. inches long in all yet sensible enough and having caus'd a hole to be made in the Cover of a Box just wide enough for the smaller end of the Glass to be thrust in at we inverted the Thermometer so that the ball of it rested upon the cover of a Box and the pipe pointed directly downwards then we placed about the ball a little beaten ice and salt and observ'd whether according to our expectation the tincted spirit that reach'd to the middle of the pipe or thereabouts would be retracted upon the refrigeration of the liquor in the ball and accordingly the spirit did in very few minutes ascend in that short pipe above an inch higher then a mark whereby we took notice of its former station and would perhaps have ascended much more if the application of the frigorifick mixture had been continued by which and another succeeding Experiment to the same purpose it seems that the condensation of liquors by cold is not always effected by their proper gravity only which ordinarily may be sufficient to make the parts fall closer together but whether in our case the contraction be assisted by some little tenacity in the liquor or by the spring of some little aerial or other spirituous and Elastick particles from which the instrument was not perfectly freed when it was seal'd up or which happened to be generated within it afterwards will be among orher things more properly inquir'd into in another place where we may have occasion to make use of this Experiment There is a famous Tradition that in Muscovy and some other cold Countries 't is usual out of Ponds and Rivers to take up good numbers of Swallows inclos'd in pieces of ice and that the benumm'd birds upon the thawing of the ice in a warm room will come to
I mean the heating of quick-Lime in cold water I confess I cannot but admire the Laziness and Credulity of Mankind which have so long and generally acquiesc'd in what they might so easily have found to be false This I say because I was possibly the first that has had both the curiosity and boldness to examine so general and constant a Tradition yet I doubt not that you will soon be brought to take it as well as I for as great as popular an error For to let you manifestly see how little the Incalescence of the quick-Lime needs be allowed to proceed from the coldness of the ambient water if instead of cold water you quench it with hot water the Ebullition of the liquor will not only be as great as if the water were cold but oftentimes far greater As I have sometimes for curiosity removed boiling water from the fire and when the liquor had left of boiling but was yet scalding hot I put into it a convenient quantity of quick-Lime and after a while the water which as I said had ceas'd from boiling began to boil afresh with so much vehemence and such large and copious bubbles that it threatned to run over the Pot of which before the effervescence a considerable part was left unfill'd And this was no more then what I might well look for hot water being much fitter then cold to pervade nimbly the body of the Lime and hastily dissolve and set at liberty the igneous and saline parts wherewith it abounds And how much a greater interest salts may have in such incalescencies then Cold I have also taken pleasure to try by pouring Acid spirits and particularly spirit of salt upon good quick-Lime For by this means there would be a far greater degree of heat excited then if I had instead of spirit of Salt used common water And this whether I imploy'd the spirit cold or hot For in either case so small a portion as about the bigness of a Walnut of Lime put into a small glass would by the addition of a little spirit of Salt put to it by degrees both hiss and smoak and boil very surprizingly and notwithstanding the small quantity of the matter would conceive so great a heat that I was not able to hold the glass in my hand And to show some friends how little heat excited in quick-Lime by cold water proceeds barely from the coldness of that liquor I caus'd a parcel of good Lime to be beaten small and putting one part of it into a glass vessel I drench'd it plentifully with oyl of Turpentine more then it would imbibe and the other portion of the Lime I likewise drench'd with common water both these liquors having stood in the same room that they might be reduc'd by the same Ambient Air to a like degree of coldness the event of this Trial was what I look'd for that the oyl of Turpentine notwithstanding its actual coldness and the great subtilty and piercingness of parts which it has in common with other Chymical oyls being of an incongruous Texture seem'd not to make any dissolution of the powdered Lime and did not for several hours that I kept it produce that I perceived any sensible heat in the Lime Whereas to show that 't was not the fault of the Lime that part of it on which common water had been poured did after a little while conceive so strong a heat that it broke a large openmouth'd-glass into whose bottom it was put and not only grew so hot that I could not endure to hold it in my hand but sent out at the mouth of the glass though that were considerably distant from the Lime a copious white fume so hot that I could not well suffer the holding of my hand over it And to prevent a possible though invalid objection which I foresaw might be drawn against the Experiment made with oyl of Turpentine from the Oleaginous Nature of that liquor I covered a piece of the same sort of quick-Lime I have been speaking of with highly rectified spirit of Wine but though I left them together all night yet I perceived not that the liquor had at all slack'd the Lime which continued in an intire lump till upon the substituting of common water it did as I remember quickly appear to be slack'd since it fell assunder into a kind of minute white powder which was bating the colour almost like mud and would easily by a little shaking be disperst like it through the water 15. Eleutherius I ingeniously confess to you Carneades that what you say surprizes me for I thought it superfluous to try my self so acknowledged an Experiment being not able to imagine that so many learned men for so many Ages should so unanimously and confidently deliver a matter of fact of which if it were not true the falsity could be so easily discovered 16. Carneades For my part Eleutherius I confess I am wont to doubt of what they teach that seldom or never doubt And I hope you will forgive me if having found an assertion so general and uncontroul'd of a falsity so easie to be disprov'd I be inclinable to suspect the Truth of their other inferior Traditions about Antiperistasis and of these I will mention the two chiefest I have met with among the moderns for being contriv'd Experiments I presume you will easily believe they came not from Aristotle nor the Ancienter Schoolmen that commented upon Him 17. The first of these is the freezing a Pot to a Joynt-stool by a mixture of snow and salt by the fires side in which case 't is pretended that the fire does so intend the cold as to enable it to congeal the water that stagnated upon the surface of the stool betwixt That and the bottom of the Pot. But how little need there is of Antiperistasis in this Experiment you may guess by this that I have purposely made it with good success in a place in which there neither was nor ever probably had been a fire the room being destitute of a Chimney And this Trial of mine I could confirm by divers other Experiments of the like nature but that this one is sufficient 18. I proceed therefore to the other Experiment which is delivered by very learned men and for whom I have a great respect according to these if you take a somewhat large Pot and having fill'd it almost with snow place in the midle of the snow a Vial full of water this Pot being put over the fire the coldness of the snow will be so intended by the heat from which it flies into the water that it will turn that liquor into ice But though I several times tri'd this Experiment yet neither in earthen nor in silver vessels could I ever produce the promised ice And I remember that an eminently learned man that wondered to find me so diffident of what he said he knew to be true readily undertook to convince me by an Ocular proof but with
a far deeper colour and bitterer taste in the middle and towards the bottom then towards the outsides of it And whereas Barclay relates that King James being in Denmark to fetch his Queen thence in the Winter season had his nose and ears in danger of Gangreening which being timely perceived by some of the King of Denmarks Nobility they caused the parts to be rubbed with snow and so the danger was avoided the same travellers affirm that in the Northern parts where men become stiff with cold and almost frozen to death that they rub the frozen parts with snow or else cast the whole body into water by which means the whole body is crusted over with ice as Eggs and Apples are as if the freezing Atoms did pass from the body frozen into the water or snow and this way of curing Gangreens from cold Sennertus doth prescribe To make some Experiment hereof I exposed flesh and fish and found that by immersing them into water they soon became more limber and flexible and more easily yielding to the knife and compassed with a crust of ice of the thickness of about half a crown manifest tokens of their thawing and being cut they discovered nothing of ice in them This for more certainty I often reiterated as also in Eggs and Apples above a dozen times and never failed of unthawing them by this way 'T is to be noted if you immerse the flesh fish eggs or apples deep into the water no ice will appear on their outsides but only when you hold them neer the surface of the water As to the Persian Experiment mentioned by Olearius of making huge heaps of ice to be preserved for cooling of their drinks I observed that by pouring water into an open Pan or into a Flask gradually some at one time some at another I could quickly freez by this way a whole Flaskfull when near half of a Flask filled at one though helped by art was unfrozen I observed also that the ditches betwixt Southwark and Redderiff had acquired an exceeding thickness of ice caused by the flowing of the water in them at full Tide for new water being brought in by the Tide was there congeal'd to the thickness of some inches every ebbing and flowing I observed also the ice on the banks of Thames above two yards thick the inhabitants told me they had seen it three or four yards thick which thus came to pass the Tide flowing in and meeting with great flakes of ice drove them to the banks and lodged them on the ice there frozen which flakes uniting there with the former ice raised it to that excessive height or thickness Besides every one may observe in London Streets and elsewhere in Chanels where no constant current is that water coming from the houses soon fill the Chanels with thick ice for running but a little at a time it freezeth almost as fast as it cometh thither Nay I have seen ice of some yards thickness in such places where a small rill or stream of water gently falls on the side of a hill Amongst those things that will freez Mortar and Plaister of Paris were omitted and thence 't is that Plaisterers and Bricklayers play all the Winter My Lord Verulam in his natural History and some from him have affirmed to me that Apples and Eggs covered with a wet cloath will not freez but I find no difference in those that are thus covered and them that are not Add to those that sink upon congelation all oyls from Animals and from Vegetables that are extracted by expression or boiling Add to those that freez not water and Sugar boiled to the consistence of a Syrup and also all other Syrups none whereof I could ever take notice or learn by others that they would freez 'T is true that water having an equal quantity of Sugar dissolved in it will freez but with a little more mixed therewith freezeth not To try the effect of cold upon Loadstones I exposed several of them in the open Air and also within rooms in the most severe weather the needle being kept in a warm place At other times I exposed the needle to the cold air keeping the stones warm at other times both were exposed but in none of my Experiments could I conclude any thing certain to their attractive faculty for the sphere of their activity was found to be sometimes greater and sometimes less to a considerable difference in ten several good stones imployed for this purpose I essayed also to find out a standard of cold whereby to fit the tinged spirit of Wine for the Weather-glasses and to that end made use of Conduit water and the distilled waters of Plantane Poppies Black-Cherry Nightshade Scurvigrass and Horse-raddish all which were first placed in the same room where a fire was kept and then removed and measured out into spoons in equal quantities and also a drop of them dropt on the same bench but though this was often tried I could not make any sure inference from them only I observed that the black-Cherry water did for the most part freez first but the other with very great uncertainty The Horse-raddish and Scurvigrass waters were for the most part froze last The best way to discover the very beginning of freezing of liquors is to move a Pin or Needle through the liquors whereby the ice will be raised and become discernable when the naked eye can discover none at all FINIS Figure 1. Page 9 10 11 â— 98. A the Ball or Egg. B C the Stem D the little Aqueous Cylinder Figure 2. the open Weather glass mentioned pag. 24 43 Figure 3. the seal'd Weather-glass or Thermoscopâ—mentioned pag. 24 55 56. Figure 4. the Barometer oâ— Mercurial Standard placed in Frame B B mentioned pag. 25 Figure 5. an Instrumenâ— mentioned pag. 93. A the Vial. B C the Pipe cemented in t the neck of the Vial open at â— and seal'd at B. Figure 6. pag. 97. A the Bolt-head B the small Stem B C the Cylinder of wateâ— inclos'd Figure 7. pag. 101. * It was thought needless to insert Mr. Hobs's Scheme touching this subject because it only shews that Wind is the cause of Cold. Sceptical Chymist * Chapter the fifth of that Treatise * The two Essays of the Unsuccesfulness of Experiments * Another remarkable instance of the variable success of the Experiments of Cold I 〈◊〉 〈◊〉 with in an Experiment 〈◊〉 the 〈◊〉 Dr. 〈◊〉 〈◊〉 the 〈◊〉 of oyl of 〈◊〉 For though I 〈◊〉 that Liquor in smal ' vessels of 〈◊〉 〈◊〉 and 〈◊〉 and 〈◊〉 in 〈◊〉 〈◊〉 〈◊〉 〈◊〉 at one 〈◊〉 〈◊〉 〈◊〉 the 〈◊〉 of the Air in 〈◊〉 nights 〈◊〉 extraordinarily sharp 〈◊〉 〈◊〉 is more our 〈◊〉 〈◊〉 〈◊〉 〈◊〉 and Salt would 〈◊〉 the Experiment succeed 〈◊〉 that we tri'd it with several parcels of Oyl of Vitriol And yet that the Learned Doctor by the help of the Air alone for he uses not our 〈◊〉 mixture did bring that Liquor either to
by the Diary the Quicksilver to have ascended but to 29 Inches and a pretty deal less then a half Since that time being forced by several Avocations to be often absent from the place where my Thermoscopes were kept I was not careful to prosecute such Observations those already set down not to mention those that are not here transcrib'd being judg'd abundantly sufficient to evince the Paradox propos'd to be prov'd by them Only to manifest that after I desisted from registring my Observations the Phaenomena may probably have been as remarkable as before I shall add That one of the last times I chanc'd to take notice of the Difference to be gather'd by comparing the two Weather-glasses I found the weather happening to be warmer then ordinary the difference between them to exceed any that I remembred my self to have then observ'd amounting to forty four if not to forty five Divisions And ev'n since the writing of the Last Line we have had opportunity to observe a Phaenomenon which if it had occurr'd to us in the place where we might have compar'd the Barascope with the Exact Weather-glasses hitherto mention'd and whereby we had been invited to rely upon it would perhaps appear more Considerable then any of the Observations yet recorded For not very many hours ago finding in the Morning the Quicksilver to be risen in a good Barascope of mine though another from that all this while referred to and elsewhere kept above ¾ of an Inch higher then the place it rested at the Night foregoing and a somewhat Nice Weather-glass where the included Air is kept in the lower part of the Instrument which is shaped like that already describ'd in this Discourse being consulted to show what Effect so great and sudden a change of the Atmosphaeres gravity would have upon it I saw the tincted Liquor in the shank depress'd a full Inch or more beneath the Surface of the Ambient Liquor in the Viol which strange depression of the Liquor in a pipe above 20 Inches long and where the alterations of the Air as to Heat and Cold are not wont to produce any thing near so great an Effect I could not but take much notice of Since the season of the year makes it no way likely that the night though Cold could have had so powerful an Operation on it especially since an Amanuensis that watch'd it much longer then I affirms that he saw the Liquor driven down quite to the very Bottom of the pipe and a Bubble of the outward Air to make its passage through the water and to joyn with the Air contain'd in the cavity of the Viol. The II. Discourse Containing some New Observations about the Deficiencies of Weather-glasses together with some Considerations touching the New or Hermetical Thermometers ANd since I had occasion to speak of the Deficiencies of Weather-glasses and the mistakes whereto men are liable in the Judgement they make of Cold and Heat upon Their Informations it will not perhaps appear impertinent to add three or four Considerations more to excite men to the greater Wariness and Industry both in the making and using Weather-glasses and in their Judging by them 1. And first I consider that we are very much to seek for a Standard or certain Measure of Cold as we have setled Standards for weight and magnitude and time so that when a man mentions an Aker or an Ounce or an Hour they that hear him know what he means and can easily exhibit the same measure but as for the degrees of Cold as we have elsewhere noted concerning those of Heat we have as yet no certain and practicable way of determining them for though if I use a Weather glass long 't is easie for me to find when the Weather is colder or when warmer then it was at the time when the Weather-glass was first finished yet that is a way of estimating whereby I may in some degrees satisfie my self but cannot so well instruct others since I have no certain way to know determinately so as to be able to communicate my knowledge to a remote Correspondent what degree of Coldness or Heat there was in the Air when I first finished my Thermoscope For besides that we want distinct Names for the several gradual differences of Coldness we have already declar'd that our sense of feeling cannot safely be relied upon to measure them and as for the Weather-glass that is a thing which in this case is suppos'd to be no fit Standard to tell us what was precisely the temper of the Air when it self was first finished since that does but inform us of the recessions from it or else that the Air continues in the Temper it was in at the making of the Instrument but does not determine for us that Temper and enable us to express it as indeed it is so mutable a thing ev'n in the same place and oft-times in the same day if not the same hour that it seems little else then a Moral impossibility to settle such an universal procurable Standard of Cold as we have of several other things And indeed there is scarce any Quality for whose differences we have fewer distinct Names having scarce any for the many degrees of Coldness that may be conceiv'd to be intermediate betwixt Lukewarmness and the Freezing degree of Cold and even these are undefin'd enough for that which to some mens senses will feel Lukewarm by others will be judg'd Hot and by others perhaps cold nor is even the glaciating degree of Coldness well determin'd since not only differing Liquors as oyl wine and water will manifestly freez much more easily one then another but even Liquors of the same denomination and of waters themselves some are more easily turn'd into Ice then others and I see no great cause to doubt but that there may be sufficiently differing degrees of Cold whereof the mildest may suffice for the congelation of some waters I must not forget to add that the same person that has made many observations with a Weather-glass is so confin'd by that numerical Instrument that if by the spilling of the Liquor or the cracking of the Glass or the casual intrusion of some Bubbles of Air or by any of divers other Accidents that may happen the Instrument should be spoil'd he would though he should imploy again the same Instrument be reduc'd to seek out 〈◊〉 new Standard wherewith to measure the varying temperature of the Air. And though it be not difficult to include in the Cavity of a Weather-glass some other fluid Body instead of Air yet it will be very difficult if not impossible to include a Body fit to resent and show the Alterations of the Ambient Air without being also liable to receive impressions from it at the time of its being first shut up Yet I will not here omit that I have sometimes consider'd whether the essential oyl of Aniseeds which is that that is distill'd by the intervention of water in a
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
I am now upon for whilest I was yesterday writing It I had occasion to Examine by such a Seal'd Weather-glass as I have been speaking of the Temper of a certain strange kind of mixture that towards the close of this Treatise I shall have Occasion to take special Notice of and though to the touch it appear'd but Lukewarm yet having put into it the Ball and part of the stem of the seal'd Weather-glass I found the Included Liquor slowly enough impell'd up so high that at length to my wonder it rose eight or nine Inches in a Stem which was not much above a foot long but that which I relate as the surprizing Circumstance is that when I had taken out the Thermoscope and remov'd it again into a deep Glass full of Cold water whence I had just before taken it out to put it into the Anomalous mixture I had a mind to examine the Tincture in the Weather-glass did not as it was wont and as any one would have expected begin to subside again towards its former station but continued within about half an Inch or less of the very Top of the Instrument though neither my own busie Eyes nor those of a person very well Vers'd in making and using Thermoscopes could perceive that the expanded Tincture was any where discontinued by any Air or Bubbles which at first we suspected might possibly though it were very unlikely have been generated by the Tepor of the mixture But that which continued our wonder if not increased it was that during four or five hours that the Instrument continued in the Cold water and during some hours also that it was expos'd to the Air the Tincture did not subside above half an Inch and which is yet more strange having left the Glass all night in the window of a Room where there was no Chimney I found in the morning that its descent was scarce sensibly greater for it continued about eight Inches higher then the mark it stood at when I first put it into the Lukewarm mixture and how long it will yet retain this strange expansion is more then I can tell But by this and what I may have occasion hereafter to relate concerning this mixture it may appear somewhat the more reasonable to suspect that even seal'd Weather-glasses furnished with high rectifi'd spirit of Wine may in some though very rare conjunctures of Circumstances and from some peculiar Agents either by their insinuating themselves through the Pores of the Glass or on some other Account receive impressions that as far as can easily be discern'd are not purely the genuine and wonted Operations of Heat and Cold. The Chymist Orthelius tells us that the Liquor distill'd from the Oar of Magnesia or Bismute which seems to be the same Mineral that we in English call Tin-glass will swell in the Glass 't is kept in not only manifestly but very considerably at the full Moon and shrink at the new Moon and if all my endeavours to procure that Oar had not prov'd fruitless I should be able by my own Experience to disprove or confirm so admirable a Phaenomenon but being as yet unfurnish'd to make the Trial my self lest it might appear a Vanity so much as to mention without rejecting it a thing so very unlikely I shall add that since I find the Thing for the main which was delivered by the Chymist imploy'd as an Argument by a famous Mathematician the Jesuite Casatus whose expressions are such as if he himself had observ'd that even in stopt Glasses the foremention'd Mineral spirit increased very sensibly in Bulk about the time of the full Moon which wonder being admitted may not only countenance what we were saying but hint some other very strange things in Nature This brings into my mind what I have elsewhere mention'd that a Tincture of Amber I had made with high rectifi'd spirit of Wine did for many Moneths in a well stopt Glass discover it self to be affected with certain changes which were thought to proceed from some secret mutations of the Air that did sensibly so work as I had not observed it to do upon other Liquors wherein the spirit of Wine abounded And perhaps upon long and diligent observation one might find a Disparity betwixt Weather-glasses kept in the same place but furnished with differing Liquors a Disparity I say that could not be so well ascrib'd to any thing as to the peculiar Nature of the Respective Liquors which though of divers kinds may to add that towards the facilitation of Trials be made of a very conspicuous colour by the self-same Metal Copper which not only gives the Known colour in Aqua fortis but affords a fair solution in Aqua Regis and it makes a Liquor of a most deep and lovely blew in spirit of Urine or of Sal Armoniack and the like nay I have found that in good Chymical Oyl of Turpentine for express'd oyls are too easily congeal'd the bare filings of it will yield a sufficient Tincture But because it is yet but a bare suspicion that Seal'd Weather-glasses made of differing Liquors but in other points alike may be otherwise then uniformly affected by the Temperature of the External Air I shall now add an observation already made to show that even the Seal'd Weather-glasses furnish'd with spirit of Wine are not so perfectly secluded from all commerce with external Bodies and liableness to their operations but that they may be wrought upon otherwise then we think For I have more then once observ'd that even in seal'd Thermoscopes made purposely at home for me and with great care by the expertest maker of Them after a good while and when no such matter was expected there have emerg'd Bubbles which whether they proceeded from some undiscernable Particles of Air harbour'd in the Pores of the Water which in process of time by their Union came to make conspicuous Bubbles or from some dispos'd particles of the spirit of Wine it self by successive alterations brought to a state of Elasticity I now examine not but only affirm that sometimes I have had of these Bubbles great enough to possess the space of many Inches in the shank of a long seal'd Weather-glass and I have been troubled with them in more Weather-glasses then one or two which I therefore take Notice of not only because it serves to prove what I was saying but because it is very fit an Advertisement should be given of it to prevent mistakes For when these Bubbles are small and are generated or happen to stay at or about the Place where the Sphaerical and Cylindrical parts of the Glass meet they may easily as I have observ'd lurk unheeded and reaching from side to side so divide the spirit of Wine in the Ball from That in the Stem that the latter shall not be able 〈◊〉 rise and fall according to the changes of the weather the Bubble notwithstanding its aerial nature being more indispos'd to be mov'd up and
down in the slender Stem of a small Weather-glass then the spirit of Wine it self as we have elsewhere shown that when Air is not forc'd a Bubble of it will not in several cases so readily pass through a very narrow passage as would that grosser fluid Water But all these difficulties not to call them extravagances which I have been mentioning about seal'd Weather-glasses I represent not to show that it is at least as yet worth while to suspect ours so far as to imploy all the Diligence and Inventions that were 〈◊〉 to prevent or silence the suspicions of a Sceptick or that might be thought upon in case the matter did require or deserve such extraordinary Nicety but only to give men a rise to consider whether it would be amiss to take in when Occasion presents it self as many collateral Experiments and Observations as conveniently we can to be made use of as well as our Sensories and Weather-glasses in the Dijudications of Cold. And perhaps an Attentive Enquiry purposely made would discover to us several other Bodies Natural or Factitious which we might make some use of in estimating the degrees of Cold. For though to give an instance 〈◊〉 be thought the Liquor that is most susceptible of such an Intensity of Cold as will destroy or suspend its Fluidity yet not here to repeat what we formerly deliver'd of the easie congealableness of Oyl of Aniseeds we have as we elsewhere note to another purpose distill'd a substance from Benzoin which becomes of a fluid a consistent Body and may be reduc'd to the state of fluidity again by very much lesser alterations of the Ambient Air as to Heat and Cold then would have produc'd Ice or Thaw'd it I could also here take notice of what I have sometimes observ'd in Amber-greese dissolv'd in high rectifi'd spirit of Wine or in other Sulphurous or Resinous concretions dissolv'd in the same Liquor for now and then though it seem'd a mere Liquor in warm Weather it would in Cold weather let go part of what it swallow'd up and afterwards redissolve it upon the return of warm weather some of these concretions as I have seen in Excellent Amber-greese shooting into fine figur'd masses others being more rudely congeal'd And I might also add what I have observ'd in Chymical Liquors not unskilfully prepar'd out of Urine Harts-horn c. which would sometimes seem to be totally clear Spirits and at other times would suffer a greater or lesser proportion of Salt to Chrystallize at the Bottom according to the Mutations of the Weather in point of Cold and Heat Such kind of instances I say I could mention but I shall rather chuse to prosecute my Examples in that obviousest of Liquors Water and add that even That may afford us other Testimonies of the increased or lessen'd cold of the Air then that which it gives us in Common Weather-glasses For in some parts of France the Watermen observe that the Rivers will bear Boats heavier loaden in Winter then in Summer and I have upon inquiry been credibly inform'd that Seamen have observ'd their ships to draw less water upon the Coasts of frozen Regions where yet the Sea is wont to be less brackish then they do on our British Seas which argues that water is thicker and heavier in Winter then in Summer Nay I shall add that not only in differing Seasons of the Year but even at several times of the same day I have often observed the Coldness of the Air to be regularly enough so much greater at one time of the day then at another that a Glass bubble Hermetically seal'd and pois'd so as to be exactly of the same weight with its equal Bulk of Water as that Liquor was constituted at one time of the Day would about Noon when the warmth that the Summers Sun produc'd in the Air had somewhat rarifi'd the water and thereby made it bulk for bulk somewhat lighter then before the Bubble would sink to the Bottom of the water which for the better marking the Experiment I kept in a Glass-Tube but when at night the coolness of the Air had recondens'd the water and thereby made it heavier it began by little and little to buoy up the Bubble which usually by morning regain'd the Top of the Water and at other times of the day it not unfrequently happen'd that the Bubble continued swimming up and down betwixt the Top and the Bottom without reaching either of them sometimes staying so long in the same part of the Tube that it much surpriz'd divers of the Virtuosi themselves who thought the poising of a weight so nicely not only a very great difficulty as indeed it is but an insuperable one But of this Experiment I elsewhere say more and because about other Weather-glasses I have said so much already I think it may not be improper to Sum up my thoughts concerning the Criteria of Cold by representing the following particulars 1. That by reason of the various and unheeded predispositions of our Bodies the single and immediate informations of our senses are not always to be trusted 2. That though Common Weather-glasses are useful Instruments and the informations they give us are in most cases preferrable to those of our sense of touching in regard of their not being so subject to unheeded mutations yet ev'n these Instruments being subject to be wrought upon by the differing weights of the Atmosphaere as well as by Heat and Cold may upon that and perhaps some other accounts easily mis-inform us in several cases unless in such Cases we observe by other Instruments the present weight of the Atmosphaere 3. That the seal'd Weather-glasses we have been mentioning are so far preferrable to the Common ones as especially they not being obnoxious to the various pressure of the external Air that there seems no need in most cases to decline their reports or postpose Them to those of any other Instruments But yet in some nice Cases it may be prudent where it may conveniently be done to make use also of other ways of examining the Coldness of Bodies that the concurrence or variance to be met with in such ways of Examination may either confirm the Testimony of the Weather-glass or excite or assist us to a further and severer inquiry 4. That I would not have Men too easily deterr'd from devising and trying various Experiments if otherwise not unlikely or irrational about the estimating of Cold by their appearing disagreeable to the vulgar Notions about that Quality For I doubt our Theory of Cold is not only very imperfect but in great part ill grounded And I should never have ventur'd at trying to make seal'd Weather-glasses if I could have been withheld either by the grand Peripatetick Opinion that to shun a void water must remain suspended in Glasses where if it fall the Air cannot succeed it or the general opinion ev'n of Philosophers as well new as old That Air must be far easier then any visible Liquor
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
ingenious modern Naturalists who acknowledging that the Air has a weight which Mr. Hobs also does in effect admit though he make not so good use of it as they do by that explicate the ascension of water in Weather-glasses teaching that the Cold of the Ambient Air making the included Air shrink into far less room then it possest before the water in the subjacent Vessel is by the weight of the incumbent Air which presses on it more forcibly in all the other parts of its surface then it is press'd upon in that included in the shank impell'd up into that part of the shank which was newly deserted by the self-contracting Air. But though this Account be preferable by far to those which we mention'd before it and though it be not only ingenious but as far as it reaches true yet to me I confess it seems not sufficient and therefore I would supply what is defective by taking in the pressure and in some cases the spring of the external Air not only against the surface of water for That the newly mention'd explication likewise does but also against the internal or included Air. For the recited Hypothesis gives indeed a rational account why the water is impell'd into the place deserted by the Air but then supposes that the Air is made to contract it self by cold alone when it makes room for the water that succeeds in its place whereas I am apt to think that both the effects may proceed at least in great part from the same cause and that the pressure of the contiguous and neighbouring Air does according to my Conjecture eminently concur to reduce the cool'd Air shut up in the Weather-glass into a narrower space This it does in common Weather-glasses because the Ambient Air retains the whole pressure it has upon the Account of its weight whereas the internal Air by its refrigeration even when but equal to that of the External Air looses part of the pressure it had upon the account of its now weakned spring But this as I newly intimated is not the sole account upon which the Air may in some sorts of Weather-glasses impel up the water and contribute to the condensation of the Air incumbent on the water For in some circumstances one or two of which we shall produce by and by it may so happen that the rest of the Air that bears upon the water to be rais'd will not be so much refrigerated as the included Air that is to be condens'd and consequently the other Air will have a stronger spring then this last mention'd Air will retain and therefore the former will have a greater pressure then the latter will be able to resist We shall not now examine whether the spring of the Air depend upon the springy structure of each aerial Corpuscle as the spring of wool does upon the Texture of the particular hairs it consists of or upon the agitation of some interfluent subtile matter that in its passage through the aerial particles whirles each of them about or upon both these causes together or upon some other differing from either of them but this seems probable enough that as when Air being seal'd up in a Glass is afterwards well heated though it acquire not any greater dimensions as to sense then it had before yet it has its spring much increased by the Heat as may appear if the seal'd Tip be broken under water by the eruption of Bubbles by the indeavour of the imprison'd Air to expand it self so upon the refrigeration of the Air so seal'd up though the additional spring if I may so speak which the Heat gave it will be lost upon the recess of that Heat or as soon as the effect of that heat is distroy'd yet there will remain in the included Air a considerable spring and sufficient to make it as well fill at least as to sense the cavity of the seal'd Glass as it did when its spring was stronger And proportionably we may conceive that though Cold at least such as we meet with in this climate of ours do make the spring of an included parcel of Air weaker then it was before the refrigeration of that Air yet it may not make it so much weaker but that the aerial Corpuscles may be kept so far extended as not at all or scarce sensibly to quit the room they possest before in case there be not contiguous to them any other Body which by its pressure indeavours to thrust them inwards and so make them desert part of that space which clause I therefore add because that if the case propos'd do happen 't is obvious to conceive that the weakned spring of the Air cannot retain so much force to resist an external pressure as it would have if the Cold had not debilitated it and consequently this cooled Air must yield and suffer it self to be condens'd if it come to be expos'd to a pressure to which it was but equal before its being weakned And such in common Weather-glasses is the pressure that is constantly upon the surface of the water without the Pipe upon the account of the gravity of as much of the Air or Atmosphaere as comes to bear upon it Having thus explain'd our conjecture we will now proceed to the Experiments we made to countenance it as we find them entred in our loose notes In one of which I find what follows We took a Viol capable of containing five or six ounces of water and having fill'd it almost half full with that Liquor we inverted into it a Glass-pipe of about 10. Inches long and much bigger then a large Swans Quill seal'd at one end and at the other fill'd top full with water so that the open Orifice being immers'd under the Vessell'd water of the Viol there remain'd no Air at the Top of the Pipe Then as much of the Orifice of the Viols neck as was not fill'd by the pipe being carefully clos'd with Cement that no Air could get in or out the Viol was plac'd in snow and salt till the vessell'd water began to freez at the Top and Bottom And according to our expectation we found that notwithstanding this great degree of infrigeration of the Air in the Viol the water in the Pipe did not at all descend So that either the Air did not shrink by so great a Cold or the water whether to avoid a vacuum or otherwise did not remove out of the Pipe to possess the place deserted by the refrigerated Air. Afterwards we endeavoured to repeat the Experiment with the same Glasses but having had occasion to be absent a little too long though not very long we found at our return the upper and seal'd part of the pipe beaten out which we suppos'd to have been done by the intumescence of the water in the Viol upon its glaciation Wherefore we fastned into the same Viol another Pipe some Inches longer then the former and drawn very slender at the seal'd end that it might
easily be broken there and having set the viol to freez as before without finding the water to descend in the Pipe we did with a forceps break off the slender seal'd end that the outward Air might come to press upon the suspended water and by it upon the cool'd Air in the viol whereupon as we expected the water was swiftly depress'd by our estimate eight or ten Inches but not so low by a pretty deal as the surface of the water in the viol After this by rarifying the Air in the Viol and by blowing into it through the pipe the water was rais'd within about half an Inch of the Top of the Pipe whose slender end being seal'd the viol was again plac'd in snow and salt but the spring of the Air at the Top which was rarifi'd before was by refrigeration so weakned that it was unable sensibly to depress the water wherefore breaking off the Apex as before the upper Air immediately drove it down divers Inches Our last Tryal therefore was to leave in the same Pipe about 3 ½ Inches of Air rarifi'd as little as we could and placing the viol in salt and snow as before we observ'd that the Air in the Pipe did upon the refrigeration of the Air in the viol expand it self very little though the water in the Viol were in part turned into Ice but upon breaking off the slender seal'd end the outward Air presently depress'd the water above two Inches beneath the last level and by removing the Glass into a warmer room we found that the water ascended a pretty deal above an Inch higher then the same uppermost level whereby we probably concluded our Weather-glass to be stanch Thus much I find together in one place among my promiscuos collections but after this coming to have the conveniency of Glasses so shap'd as to be easily seal'd I judg'd it fit to make use of some of them to keep ev'n the most suspicious from objecting that I should also have made some Trials with Glasses which being Hermetically seal'd would be sure most accurately to hinder all immediate Intercourse betwixt the internal and external Air. And I remember that once we took a Glass like the Bolthead of a common Weather-glass save that the small End was drawn very slender for the more easie breaking of the Apex And into this Glass a convenient Quantity of water was powr'd and then the Glass being seal'd up at the sharp end and inverted the water fell down to that end and possest its due space in the Pipe Then the round end of the Glass having a mixture of snow and salt appli'd about it though the internal air must needs have been thereby much refrigerated as will be readily granted and may be gather'd from divers of the Experiments mention'd in these papers yet we observ'd not the water manifestly to rise And though an attentive Eye should in such a Trial discern some sensible intumescence in the water yet that may well enough proceed from some little expansion of the Aerial particles which we have elsewhere shewn to be usually latitant in Common water upon the diminution of the pressure of the Air above the water caused by weakning that air's spring by the Cold. But when we had to complete the Experiment broken the slender end of the Glass under water the included air becoming then contiguous to water that had obtain'd immediate Intercourse with that water whose surface was every where prest by a pillar of the External air that leaned upon it the water was by the gravity of that outward air hastily impell'd into the Cavity of the Pipe the spring of whose air was as we said weakned by the Cold to the height if I misremember not of several Inches Another sort of Trials I remember we made after the following manner We took Glass Bubbles blown with a Lamp some of about the bigness of a Nutmeg and some much greater each of these Bubbles we furnished with a very slender stem often no bigger then a Ravens Quill which was usually divers and sometimes many Inches long Into this stem a drop or two of water being convey'd might easily enough by reason of the Lightness of so little Liquor together with the slenderness of the Cavity which permitted not the included air to penetrate the water at the sides but rather impel up the intire Body of it be kept suspended and so betray very small changes and much smaller then to be taken notice of by common Weather glasses as to rarefaction and condensation in the air it lean'd upon Now when in one of these Instruments if watching when the pendulous water was somewhat near the Top of the stem we nimbly applied to the Orifice of that stem the flame of a Candle we could by that Heat almost in a moment seal it up by reason of the thinness of the Glass and the slenderness of the stem And if then we plac'd the thus seal'd Glass in a mixture of snow and salt how much soever the air within the cavity of the Ball must be in all probability refrigerated by this operation yet it would scarce sensibly and not at all considerably shrink as we gather'd from the pendulous waters remaining in the same place or its falling at most but inconsiderably lower But if then with a pair of Scissars or otherwise we dexterously broke off the seal'd end of the stem and thereby expos'd the internal refrigerated to the pressure of the external air the water immediately would be hastily thrust down sometimes divers Inches below its former station and sometimes quite into the cavity of the round end of the Glass To which we shall add that not only when these Thermometers were seald neither the usual degrees of Cold nor those of the Heat in the Ambient Air would at all considerably depress or raise the pendulous water which if the Glass were not seal'd would as we formerly noted shew it self wonderfully sensible of the mutations of the Air as to those two Qualities But we sometimes purposely tri'd that though upon the refrigeration of the sormerly rarified air in the Glass the pendulous water were descending fast enough yet if ev'n then we nimbly seal'd up the open Orifice of the stem which may easily be done in a trice the descent of the water would be presently stopt and it would stay either just in or very near the same part of the shank wherein it chanc'd to be when by sealing of the Glass it came to be fenced from the pressure of the Atmosphaere and in that place it would continue till the seal'd end were broken off For then in case the ambient air were as cool as it was when the Glass was seal'd the water would for the reason already given be further deprest according as the weakned spring of the inward rarifi'd air was more or less remote from an equality to the pressure of the ambient air Besides for further Trial we took a large
Glass-egg with a long stem which stem was purposely so bent that it represented a glass-Syphon in whose shorter leg the glass was drawn very small that it might be the more easily first seal'd and then broken This done we got in a convenient Quantity of water which ascended to a pretty height in both the legs of the bent glass after which the shorter leg being nimbly seal'd after the manner hereafter to be mention'd there remained a pretty Quantity of air above the water in that shorter leg which was purposely left there that it might by its spring impel up the water in the longer leg upon the refrigeration of the Air included in that longer leg All this being done the whole glass was so plac'd in a convenient frame that the oval part of it was supported by the frame beneath which the bended shank of the Weather-glass did hang so that a mixture of Ice and Salt might be conveniently laid upon this frame to surround and refrigerate the air included in the Egg without much cooling the air in the Cylindrical part of the Glass The account that I find of this Trial in one of my notes is this In the greater bent Egg that was seal'd up with water in both legs upon the application of Ice and Salt to the Ellipsis at a convenient time the water in the longer leg ascended a little but not by our guess above a barley Corns length if near so much and about four Inches of air as I remember that were left in the shorter leg expanded it self to sense as much but as soon as I broke off the slender wire wherein the shorter leg ended the external air rushing in made the water rise about two inches and a quarter in the longer leg and then there not being water enough broke through it in many bubbles Thus far the note to which I shall only add that in this case the ascension of the water in the longer leg cannot be attributed to the weight of the air in the shorter leg that being I know not how much too small to lift up so much water but to the spring of that air And also that we need not marvel the Expansion of that 〈◊〉 should be so small since some of the Experiments 〈◊〉 to be related will shew us that the refrigeration of the air in such Trials as that newly 〈◊〉 does not weaken the spring of it any thing near so considerably as one would expect So that the air in the longer leg could yield but a very little to that in the shorter leg especially since the smallness of this last nam'd portion of air made its spring to be more easily and considerably weakned by a small Expansion Thus far our Paradoxical Discourse which contains divers particulars that being added to the considerations whereunto we have by way of Appendix subjoyned It might afford us several Reflections But having dwelt too long on one subject already we shall now conclude with This upon the whole matter That there is somewhat or other in the Business of Weather-glasses which I fear we do not yet sufficiently understand and which yet I hope that by other Trials and more heedful Observations we shall discover The Paper that was prefixt by way of a short Prefatory Address to the ensuing History of Cold when being to be brought in and presented to the Royal Society it was put into the hands of its most worthy President the Lord Viscount Brounker was as followeth Little-Chelsey Feb. 14. 1662. S. A. My Lord THe time Your Lordship and the Society appoint me for the bringing in of my Papers concerning Cold is so very short that to give You the fruits of my Obedience as early as You are pleased to require them I must present them You very immature and I should say very unsit for your Perusal if you were not aswel qualified to supply Deficiencies and Imperfections as to discern them For of all the Old Observations I made divers years ago in order to the History of Cold I have not yet found enough to fill up one Sheet of Paper And as for those I made the last Frosty season besides that I was several times diverted by Avocations distracting enough the same sharpness of the weather which gave me the Opportunity of making some Experiments brought me an Indisposition which by forbidding me to be 〈◊〉 and stay long in the cold Air hindred me from making divers others and which is worst of all whilest I was confin'd to a place where I wanted divers Glasses and other Instruments I would have employ'd the ways both by land and water were so obstructed by the snow and ice that I could not seasonably procure them from London and was thereby reduc'd to leave several trials I should have made 〈◊〉 ther unattempted or unprosecuted But lest You should think that what I intend only to excuse my unaccurateness is meant to excuse my Pains I shall without further Apology apply my self to do what the shortness of the time will allow me which is little more then to transcribe into this Historical Collection most of the Particulars which Your Lordships Commands exact though haste will make me do it in the very words for the most part that I find them in a kind of Note-book wherein I had thrown them for my own private use which I the less scruple now to do not only because the haste that exacts from me this way of writing may serve to excuse it in me but that it may the better appear how little I had design'd to 〈◊〉 or byass them to any preconceiv'd Hypothesis THE EXPERIMENTAL HISTORY OF COLD Begun Title I. Experiments touching Bodies capable of Freezing others TO go Methodically to work we should perhaps begin with considering what subjects are capable or not capable of harbouring the Quality we are to treat of And to invite us to this it seems probable enough that among the Bodies we are conversant with here below there is scarce any except Fire that is not at some time or other susceptible of actual Cold at least as to sense And ev'n concerning Fire 〈◊〉 till that difficulty be clearly determin'd which we have elsewhere started namely whether Fire be not as Wind at least like such as is made by Air blown out of a pair of Bellows rather a state of Matter or Matter consider'd whilest it is in such a kind of Motion then a distinct and particular species of natural Bodies there may remain some Doubt since we see that Bodies which may be either in a Moment as Gunpowder or as far as sense can judge totally as high rectifi'd spirit of Wine turn'd into fire may yet immediately before their Accension be actually Cold And as to Gunpowder presently after Accension its scatter'd Parts caught in clos'd Vessels will also appear cold to the Touch. But such things nevertheless we must not now insist on partly because it requires the resolving of a somewhat difficult Question
which more properly belongs to the Considerations about Heat where we have already handled it partly because our Design in the following Collections was not so much to gather and set down Observations that were obvious to any that was furnish'd with a Mediocrity of Attention as Experiments purposely made in order to the History of Cold and partly too because in this Collection though we do as occasion serves take notice of some Experiments and Phaenomena that relate to Cold in General or indefinitely yet our chief work has been to find out and deliver the Phaenomena of Congelation or of that intense Degree of Cold which either does freez the Bodies it works upon or at least were capable of turning common water fitly expos'd to it into Ice And this may serve for a general Advertisement about the ensuing Papers and consequently having premis'd it we shall without any further Preamble proceed to the setting down such things as we have tri'd and observ'd concerning those Matters beginning with those that belong to the Title prefix'd to the first Part or Section of our History 1. The Bodies that are cold enough to freez others are in this climate of ours but very few and among the most remarkable is a Mixture of Snow and Salt which though little known and less us'd here in England is in Italy and some other Regions much employ'd especially to cool Drinks and Fruits which men may easily do by burying in this mixture Glasses or other convenient vessels fill'd either solely with Wine or other Drinks or else with water that hath immersed in it the fruits to be refrigerated 2. The Circumstances we are wont to observe in making and employing this mixture we shall hereafter in due place deliver and therefore here we shall only take notice that we could not find upon some trials that such Glasses filled with water as would be frozen easily enough by this mixture of Snow and Salt would be in like manner frozen in case we employ'd Snow alone without mingling any Salt with it I deny not that 't is very possible that in very cold Countries as well Snow as beaten Ice may freez water powred into the Intervals of its Parts But there is great odds betwixt water so intermingled with Ice or Snow and only surrounded with it in a vessel where the water is as it were in one entire Body and of a comparatively considerable thickness And there is also a great Difference betwixt the degrees of coldness in 〈◊〉 Air of Frigid Regions and of England And perhaps too there may be some Disparity betwixt the Degrees of Coldness of Ice and Snow in those Climates and in ours And we must have a care that in case a Vial full of water buri'd all night should freez we ascribe not the Effect to the bare Operation of the Snow which may be entirely or in great Part due to the coldness of the Air which would perhaps have perform'd the Effect without the Snow 3. But though Snow and Salt mixt together will freez water better then Snow alone yet we must not think that there is any such peculiar vertue in Sea-salt to enable Snow to freez but that there are divers other Salts each of which concurring with Snow is capable of producing the like Effect For we found upon trial that we could freez water without the help of Sea salt by substituting in its place either Nitre or Alume or Vitriol or Sal Armoniack or even Sugar for either of those being mingled with a due proportion of Snow would serve the turn though they did not seem equally to advance the congealing power of the Snow nor scarce any of them did do it so well as Sea salt But of this elsewhere more 4. When we had made the newly mentioned trials some particular conjectures we have long had about the nature of Salts invited us to try whether uotwithstanding the comminution and consequent change produced in Salts by Distillation the Saline Corpuscles that abound in the distill'd liquors of those concretes as well as in their solutions would not likewise by being mixt with it enable Snow to freez water at least in small and slender Glasses This we first went about to try with good spirit of Salt but we found as we fear'd that though it made a sufficiently quick dissolution of the Snow it wrought upon yet its fluidity hindered it from being retain'd long enough by the Snow to the bottom of which it would fall before they had stay'd so long together as was requisite to freez so much as a little Essence-bottle full of common water 5. Wherefore we bethought our selves of an expedient whereby to try the operation not only of those spirits but of divers other bodies which were unapt for a Due commixture of Snow after the way newly mention'd or of which we had too little or valued them too much to be willing to spend quantities of them upon these trials And this way that remains to be mention'd we somewhat the better lik'd because the Experiments made according to it would also prove Experiments of the transmission of Cold through the extremely 〈◊〉 〈◊〉 of Glass And even in this way of trying we did at first meet with a discouragement which least it should happen to others we shall here take notice of namely that having put a convenient quantity of Snow into a somewhat thick green glass Vial though we copiously 〈◊〉 mixt with it a somewhat weak spirit of salt being loath to imploy the best we had and having well stopt the vessel did carefully 〈◊〉 together and thereby agitate the mixture in it yet the Glass appeared only bedew'd upon the outside without having there any thing frozen But suspecting that the thickness of the Glass might be that which hindred the operation of the included mixture we put snow and a convenient proportion of the self same spirit of salt into a couple of thin Vials one of which we clos'd exactly and the other negligently and having long shaken them we found that what adhered to them on the outside was though but somewhat faintly and thinly frozen 6. And as to this sort of Experiments we shall here observe 〈◊〉 〈◊〉 all that the Snow or Ice included 〈◊〉 with the Saline Ingredient whatever that were was always thaw'd within the Glass and that consequently 't was the condens'd vapor of the Air or other liquor that adhered to the outside of the glass which was turn'd into Ice which is the Reason why in mentioning these Experiments we often use the word freez in a transitive sense to signifie the operation of the frigorifick mixture upon other bodies 7. This premised let us proceed to relate that we afterwards took Oyl of Vitriol and mixing it with Snow in such an other vial as that last mentioned we found its freezing power far greater then that of spirit of salt And least it should be pretended that in these Experiments the cold was not transmitted
through the sides of the glass but that the Air within the vial highly refrigerated by the mixture Did upon the account of their free intercourse enable the Air contiguous to the outside of the vial to freez the Dew it met with sticking on it we prosecuted the Experiments with the addition of this circumstance that on several occasions we seal'd up the vial that contained the 〈◊〉 and the other frigorifick body it was mixt with and afterwards by the help of this mixture froze the externally adhering moisture 8. Having then according to this way substituted spirit of Nitre for oyl of Vitriol or spirit of Salt we found that it froze yet more powerfully then either of those two liquors and continued to do so in those parts of the outsides of the glass that were adjacent to the included snow till that snow was almost totally resolv'd into a liquor This we tri'd both in a thin seal'd glass and in a pretty thick glass stopp'd only with a Cork 9. Afterwards we successfully enough tri'd the Experiment with spirits less acid as not only with spirit of Vinegre but with spirit of Sugar I mean the Red Empyreumatical spirit forc'd over in a Retort which mixt with snow according to the manner of the Experiment did at length freez the externally adhering moisture But the filmes of ice were very thin and very apt quickly to disappear 10. Having thus made a number of trials with acid spirits we thought fit to make some with Urinous spirits that abound in volatile salt and accordingly having mixt spirit of Urine and Snow in an open vial and agitated them we found that the external moisture did discernably though not very strongly freez But with spirit of Sal Armoniack drawn from Quick Lime according to the way I have delivered in another Treatise the operation was quick and powerful enough 11. Having tri'd to freez water with acid and with volatile spirits 〈◊〉 we thought it not amiss to try what they would do both together and accordingly pouring upon snow both some spirit of Urine and a little oyl of Vitriol and shaking them into the snow in an open Vial we found that the mixture did freez though the glaciation in this case produced were very languid 12. Having thus tri'd salts disingag'd from their grosser parts or shattered into Corpuscles by distillation we made some trial likewise with grosser salts as with Sal Gem with a sublimate made with common Sublimate and Sal Armoniack nay and with both 〈◊〉 and Kitchin Sugar with all which among 〈◊〉 like bodies that I can now Remember the Experiment succeeded well enough also a very strong solution of Pot-ashes mixt with snow in a open single Vial did freez but that very faintly And both a very strong solution of very pure salt of Tartar and at another time a strong solution of Pot-ashes being the one as well as the other mixt and agitated with snow in a single vial produced filmes of ice though thin ones on the outside of the glass 13. After this we thought fit to make a trial of another kind of which I find this account among my Notes We filled a single vial with snow and then powred into it a convenient proportion of a strongly sweet solution of minium in spirit of Vinegre and having shak'd the mixture together we found that this sweet Sugar of Lead did as well as acid and alcalizate salts excite the cold of the snow so much as to produce filmes of ice on the outside of the glass but a parcel of the same solution being for divers hours kept in snow and salt was not thereby frozen In order to the discovery of some hints of the account upon which the above mentioned mixtures were more intensly frigefactive then snow alone we sealed up a single vial full of snow unmingled with any other ingredient and found it to thaw much more slowly then any of those parcels of snow which we had mixt with salts or spirits In prosecution of this conjecture we shall add that for ought we could find by divers trials no salt that helps not the snow to dissolve faster then else it would did inable it to produce ice though usually it did produce dew on the outside of the vial that contained the mixture and accordingly neither Chrystals of Tartar nor Borax both beaten to powder nor which is more considering what we lately noted of the effects of another sort of Sublimate would Sublimate inable the snow to freez as well the powder of Sublimate as that of Borax and that of Tartar lying for a great while in the snow undissolv'd 14. Belonging to this matter I find among my papers also this Note Water of Quick Lime made by quenching store of unslak'd Lime in common water twice tri'd would not make snow freez perhaps because though the water were kept stopt yet the liquor having been kept in the glass a twelve-moneth and more probably the spirits may have flown away which I find by inquiring of one that Drinks much Lime-water that it abounds with when fresh and grows destitute of a while after and possibly also the badness of the Lime was the cause why being mingled with snow it would not freez though all the vials that did not freez did yet gather store of dew on the outsides perhaps because of the snow whose melting alone may suffice to produce that effect 15. It may seem somewhat more strange that distilled oyl of Turpentine which is so hot and fiery a liquor should not enable snow to freez but this agrees not ill with the conjecture lately mentioned for it will hereafter appear that in oyl of Turpentine Ice dissolves slower then in Divers other liquors without excepting common water it self 16. And yet notwithstanding the bad success of this trial we were not Discouraged from making another with spirit of Wine for though according to the common opinion of Chymists and Physicians it be a mere vegetable Sulphur yet we that have elsewhere ventured to ascribe some such operations to it as Chymists would have belong to Saline Liquors did not scruple to seal up in a single vial almost filled with snow a convenient quantity of pure spirit of Wine drawn off from quick Lime the better to dephlegm it and of this mixture we found the operation more powerful then any of those we have formerly mentioned for the freezing vertue of this did not only last long both in the seal'd single vial and in another that was open but the inclosed mixture presently crusted the outside of the glass or of the neck if it were made to fill that with ice which might be taken off in flakes of good breadth or in pieces of good thickness Nay it presently froze Urine into Figured ice which might be taken off in scales 17. This last circumstance puts me in mind of another Experiment whereby we tried by a vigorous mixture of Snow and some choice spirit of Nitre we had met with
to freez liquors of more difficult conglaciation then fair water We took then some snow and mingled with it some of the newly mentioned spirit of Nitre in so luckly a proportion that it froze very vigorously and very suddenly insomuch that once almost as soon as it was set to the ground it froze the vial to the floor it was set on and the outside of the glass that contained this mixture we wetted with spirit of Vinegre which was frozen into pretty thick ice But yet not quite to forget that circumstance retaining the salt taste of spirit of Vinegre and though this mixture would not discernably freez spirit of Nitre on the outside yet it transmitted cold enough to freez weak spirit of Salt and to give Us the pleasure of seeing some Saline liquors presently turned into figur'd Ice as not only the last mentioned spirit exhibited some little as it were Saline Iceikles crossing each other and quickly vanishing but which was far prettier having often observed that Sal Armoniack being dissolved in water and the solution being put very slowly to evaporate in part but not too much away the remaining liquor would in the cold shoot into parcels ofsalt very prettily figur'd some of them resembling combs with teeth on both sides and others resembling feathers having observ'd this I say and being desirous to try whether the spirit of Sal Armoniack distilled by the help of quick Lime being put to congeal on the outside of a glass would not afford a Resemblingly figured Ice we found upon trial both that the mixture was able to freez that subtile spirit and also that it shot into Branches almost like those exhibited by such salts undistilled And it was not unpleasant to behold how upon the inclining the glass so that the freezing mixture rested a little near any part of the spirit this liquor would shoot into such branches as we have been speaking of so nimbly that the eye could plainly discern them as it were to grow and hastily overspread the surface of the glass but those Branches were wont quickly to vanish I had almost forgot to mention that I tried the freezing with snow and divers fermented Liquors undistilled instead of spirit of Wine and though the Experiments succeeded not with small Beer much less with water yet there was a glaciation though but slight produc'd not only by the addition of Wine but even by that of moderately strong Ale 18. Having observed that the Liquors and other bodies that assisted the snow to freez were generally such as hastned its dissolution we thought it not altogether unworthy the trial to examine what would be the Event of procuring a speedy dissolution of the snow by substituting bodies actually warm instead of potential hot ones Of this sort of trials I find among my Notes these two registred 1. Into a single vial almost filled with snow there was poured a pretty quantity of well heated sand that it might dissolve the snow in many places at once without heating the ambient Air or the outside of the glass but though the solution of the snow seemed to succeed well enough upon the shaking of the vessel yet the outside of the glass was only bedewed not frozen 2. Into another single vial almost filled with snow we poured some water which we judg'd of a convenient warmth and we poured it in by a funnel that had but a slender orifice beneath that the warm water might fall into the middle of the snow without Running to the sides and taking a convenient time to shake the glass we did by this way produce a very considerable degree of cold and much dew on the outside but were not satisfied that any of that dew was frozen though the success would have invited us to have made further trials in greater glasses if we had had any more snow at hand Wherefore This Experiment is to be further and more artificially tri'd 19. It is a common tradition not only among the vulgar but I presume upon their account among learned men that the oftentimes variously and sometimes prettily enough figur'd hoar frost which is wont to appear upon glass windows in mornings preceded by frosty nights are exsudations as it were that penetrating the glass-windows are upon their coming forth to the cold external Air frozen thereby into variously figured ice How groundless this conceipt is may be easily discovered if men had not so lazy a curiosity as not to try which they may do in a moment and without trouble whether the Ice be according to the tradition on the outside of the window and not contrary to it on the In-side where indeed it is generated of the aqueous Corpuscles that swiming up and down in the Air within the Room are by the various motion that belongs to the parts of fluid bodies as such brought to pass along the window and there by the vehement cold of the neighbouring external Air communicated through the glass condens'd into dew and frozen into Ice 20. And because divers modern Naturalists have taught I think erroneously that glass is easily enough pervious not only to Air but to divers subtile liquors lest the favourers of this Doctrine should object that we have ill assigned the natural cause of the ice appearing on the outside of the glass in the former Experiments which according to them may rather proceed from the subtler but yet visible parts of the excessively cold mixture of the snow and saline bodies penetrating the pores of the glass and setling on the outside of it To obviate this objection I say and to confirm what we have taught in another Treatise about the wandring of store of aqueous vapours through the Air we will add the following Experiments purposely made to evince these truths 21. At one time four ounces and a quarter of a mixture of Ice and Salt being inclosed in a vial and thereby enabled to condense the vapours of the ambient Air was by their accession increas'd 12. grains Another time a vial wherein snow weighing two ounces six drachms and an half was suffered to condense the vapid Air the dew that partly adher'd to it and partly fell from it made the whole weigh four grains more then the vial did when it was first put into the scale in which scale we found some water flowing from the dew which gave that increase of weight And here let me add by the way that the tip of This seal'd vial being broken under water suck'd in a considerable quantity of it whether because of some little rarefaction of the Air included in the sealing or because of the infrigidation of that Air by the snow or for both these Reasons or any other I shall not Now dispute 22. But other Experiments to the same purpose we made wherein the increase of weight was more considerable and that the way we used may be the better understood and the conclusion built upon it the more undiscuss'd we will add a couple
in 〈◊〉 He answered me That it did there freez much harder then in our Climate but would not that 〈◊〉 had observed be turn'd into true perfect Ice On the other hand I find the Testimony of that Ingenious Navigator Captain T. James who relating the effects of cold he met with in the Island where he and his men were forc'd to winter does in one place reckon Oyl among the Liquors such as Vinegre and Sack that ev'n in their house was firmly frozen and more expresly elsewhere All our Sack says he Vinegre Oyl and every thing else that was liquid was now frozen as hard as a piece of wood and we must cut it with a Hatchet And Olaus Magnus speaking of the fights wont to be made upon the Ice in the Nothern Regions Glacialis Congressus says he fit in Laneis Calcibus non pellibus aut Coriis unctis 〈◊〉 enim frigoris quodcunque sit unctuosum convertit in Lubricitatem glacialem There being a great Similitude in point of Inflammability and disposition to mix with many subtle Oleous Bodies betwixt spirit of Wine and Oyl and as great an affinity in divers other regards betwixt that spirit and both aqueous and saline Liquors with which it will readily mix I had a great Curiosity to know what kind of change would be produc'd in vinous spirits in case they were exposed to a cold great enough to work a visible change in their Texture I therefore solicitously inquir'd of the Russian Emperors lately mention'd Physician whether or no he had observ'd in Muscovy any manifest change produc'd by cold in Hot Waters and spirit of Wine To which he returned me this answer That common Aniseed-water and the like weak spirits would be turn'd into an imperfect kind of Ice and that ev'n the very strong spirits though they would not be turn'd into Ice would be turn'd into a kind of substance like Oyl Title III. Experiments touching Bodies Indispos'd to be Frozen 1. WE found many liquors whose subtle parts being by Distillation brought over and united into very spirituous liquors and so either totally or in great measure freed from those phlegmatickor aqueous parts that dispose Bodies to congelation could not be brought to freeze either by the cold of the external Air to which in frosty nights we exposed them or by such an Application of snow and salt as served to freez other Bodies 2. Of this sort were among acid menstruum's Aqua fortis spirit of Nitre of Salt also oyl of Turpentine and almost all I add the word almost because the Essential oyl of Aniseeds and the Empireumatical oyl of common oyl will lose their fluidity in a less degree of Cold then that of our mildest frosts I say almost all the Chymical oyls we had by us as likewise spirit of Wine and other strong spirits of fermented Liquors and even 〈◊〉 it self if it were good would very hardly be brought to afford us any Ice at all But among the many liquors that would not freez there were a few whose trials afforded us some circumstances not altogether unworthy their being mention'd As 1. I being desirous to satisfie some friends that 't was the brisk spirit of the Grapes whether resulting from or extricated and exalted by fermentation that kept all the rest of the Sack from freezing I took a parcel of that liquor that would afford us no Ice at all and by the help of a lighted candle or some other actually flaming body kindled it and letting the inflammable part burn away the remaining part of the Liquor which was by vast odds the greatest part was easily brought to freez Next when the formerly mentioned trial was made with water and Pot-ashes we likewise in another glass exposed a solution wherein the proportion of salt of 〈◊〉 in reference to the water was four times greater there being in this zij of the salt to 〈◊〉 only of water and this solution though the glass were covered with hoar frost and Ice on the outside froze not at all within And likewise when another time we made a very strong solution of salt of Tartar that was very pure and fiery it did not freez though a considerably strong solution of salt of Pot-ashes that was exposed with it did So that these Experiments about the glaciation of Lixiviate Liquors must be repeated to be reduc'd to a certainty 3. That the common express'd oyls of Vegetables will after their manner freez that is lose their fluidity and become as it were curdl'd in very cold weather is a 〈◊〉 of common observation but I had a mind to try whether or no Train oyl that is made of the fat of Animals commonly that of Whales though not by distillation properly so called yet by the help of fire would not be more capable of resisting the violence of the cold and accordingly I found that Train oyl exposed to the Air in a convenient vial continued fluid notwithstanding a more then ordinary sharpness of weather and this I tried two or three several times but at length one night proved so very cold that the next morning I found the oyl unfluid which differing 〈◊〉 seem a little to Countenance but more to disfavour the Report of Olaus Magnus who writes That whereas in Northern Regions 't is usual for strong places to lose in winter the protection afforded them in Summer by their Ditches though never so wide and deep because the frost makes them easily passable to the Enemy This inconvenicy is wont to be prevented by pouring into the Ditches the Ice if there be need being first broken great store of this Train oyl which swimming upon the surface of the water and being incongealable by the cold protects the subjacent water from the freezing violence of the cold and keeps the moats unpassable But because our Author mentions this as a known and vulgar Practice in those Icy Regions it may perhaps deserve a little Enquiry whether the Whale Oyl used by the Swedes Laplanders Muscovites and other Inhabitants of those parts be not differing either as to the Fishes 't is made of or as to the way of making it or as to the way of keeping it from such Train Oyl as we Employed unless perhaps it do already appear by the Relation of writers belonging to those Countries or of Travellers that have been in them that Olaus Magnus has in that particular as I fear he has in some others misinformed his Readers 4. We took notice that a strong solution of common Sugar was easily enough turned into Ice but on a strong solution of Sugar of Lead we could not with salt and snow work the like change and this though the trial were not negligently made which I therefore think not unworthy to be mention'd because that the two only Ingredients of this Sugar were Lead which is esteemed a very cold Body and spirit of Vinegre from which as I noted above we did by the like degree of cold
these Weather-glasses are so exceeding sensible even of the minute Differences of Heat and Cold as manifestly to discover Disparities which other Thermoscopes are not nice enough to give us any Notice of Only this Advertisement we must add about them that when we use them to examine the Coldness not of liquid but of consistent Bodies we alter a little the figure of the wide end of the Glass and instead of maing it a round bubble as we have elsewhere describ'd we make it with a flat or flattish bottom that the whole Instrument might thereon as on a Basis stand of it self upright and so being still taken up by the open and slender end for fear of rarifying the included Air which Caution is here given once for all may be transferr'd with a pendulous drop in the Pipe and plac'd sometimes on one and sometimes on another of the solid Bodies to be examined by it For if the Body 't is removed to be more or less cold then that it rested on before that coldness communicated through the Glass to the Air by which the pendulous drop is supported that Airs Expansion or Contraction will manifestly appear by the rising or the falling of the drop And thus we have taken pleasure to remove it from one kind of wood to another from woods to metals and from metals to stones c. But the Expedients that may be propos'd to improve these little Instruments to the purposes we have been treating of and the Cautions that may be added to prevent mens drawing mistaking Inferences from the Informations they seem to give them will take up more time then we are willing to spend npon an occasion that will not perhaps be thought to deserve it nor much to require any others then those we shall by and by subjoyn And therefore I shall proceed to the Experiment promis'd at the beginning of this Title or Section 2. To make so much as a tolerable Estimate of the Difference betwixt such great Degrees as are not any of them too weak to congeal water is a thing which as we have not yet known to be attempted so it seem'd not easie to be perform'd For Freezing having been commonly reputed the ultimate Effect or Production of Cold men have not been sollicitous to look beyond it And though the Disparity we find betwixt several Fits of weather all of them frosty seem to be too manifest and frequent to be probably ascrib'd to nothing but the differing Dispositions of our Bodies yet how to estimate that Difference it is not so obvious For though we should have recourse to common Weather-glasses yet they might easily deceive us since not only by estimating by them the coldest day of one Winter with the coldest day of another but in judging of the Coldness of any two days in the same fit of frosty weather there intervenes time enough to make it doubtful whether the vari'd Gravitation of the Atmosphere produce not the change observ'd in the Weather-glass Besides that admitting vulgar Thermometers could not as they easily may misinform us they are imploy'd only to give us an Account of those degrees of Cold 〈◊〉 Nature of her own accord produces in the Air but not to discover whether or no Nature assisted by Art may not produce greater And 't will easily be granted that they are yet less made use of to help us to an Estimate of this Disparity And though some guess may be made by the operations of Cold upon Liquors expos'd to it yet some as water and very aqueous Liquors will freez too soon and others as Vinous spirits will not at all that we have found here in England And though French-Wine will sometimes be brought to begin to freez yet that happens but very seldom and in many Winters not at all and leaves too great an Interval betwixt the degrees necessary to congeal Wine and sufficient to congeal Water not to mention the uncertainty proceeding from the differing strengths of the Wines 3. Upon these and other considerations we thought it requisite to make use of an Expedient whose Nature and use will be easily gathered out of the following Experiments And though by a mischance that broke my Weather-glass I have been hindred from measuring exactly in what Proportion to the whole bulk the spirit of Wine was contracted by the surplusage of Cold that was more then necessary to make water freez yet I doubt not but something of use to our present Theme may be thence collected and especially the main thing design'd will manifestly appear which is the Intensity of Cold produc'd by Art beyond that which Nature needs to employ upon the glaciating of water 4. A small seal'd Weather-glass furnished with spirit of Wine the ball being about the bigness of a large Nutmeg and the Cylindrical stem being very slender and about ten Inches long the Ball and part of the stem being immers'd in a vessel of water half buri'd in snow and salt when the water began to freez at the top the bottom and the sides but before the Ice had reach'd the Ball for fear it should break it the tincted liquor was found subsided to 5 ⅔ Divisions being half Inches and being taken out thence and Ice and Salt being immediately appli'd to the Ball the Liquor fell lower to about 1 ½ Division And that it may not be doubted but that the water though in part congeal'd remain'd warm in comparison of the spirit of Wine though uncongeal'd that had been refrigerated by the snow and salt we will add this other Experiment which we find in another of our Notes thus set down 5. The seal'd Weather-glass being kept in the water till it began to freez descended to 5 ½ Being immediately remov'd into the same snow and salt that made the water begin to freez it descended at the beginning very fast and afterwards more slowly till it came to the very bottom of the stem where it expands it self into the Ball then being remov'd into the same glass of water whence it was taken and which was well stor'd with loose Pieces of Ice it did nevertheless hastily ascend at the beginning and was soon after impell'd to the former Height of five Divisions and an half or thereabouts 6. But perhaps some amends may be made for the disaster of the Weather-glass by adding that I found by another Trial that the Condensation of Liquors by such Colds as we are wont to have or can easily produce here is nothing near so great as one would imagine And though for want of a Glass-ball furnish'd with a neck slender enough I could not make the Experiment so much to my satisfaction as perhaps else I might have done yet the goodness of the scales I made use of and some greater care then possibly every Experimenter would have imploy'd may make the following Observation Luciferous 7. We took then on a cold but not frosty day oyl of Turpentine as a Liquor whose being free from phlegm or
water we would easily be more certain of then if we had imploy'd spirit of Wine and this oyl it self we rectifi'd in a gentle heat to make it the more pure and subtle Then we took a small round vessel of clear glass furnish'd with a conveniently long stem or pipe and having first weighed the glass alone in a pair of very good scales we found it to weigh 〈◊〉 〈◊〉 56 ½ gr then putting in oyl of Turpentine till it fill'd the round part of the Glass and ascended a little way into the stem we carefully mark'd with a Diamond on the outside of the Glass how high it reach'd and then weigh'd the Glass and the Oyl together which weigh'd 〈◊〉 〈◊〉 and 34 ½ gr then we put in by degrees a quarter of a Drachm and with a Diamond carefully mark'd how high it reach'd in the pipe and so we continued putting in several Quantities of oyl still carefully weighing each parcel in the scale and marking its height on the outside of the Glass which we did in order to a certain design and found it a work tedious and troublesome enough till the Liquor and the Glass together weighed 〈◊〉 〈◊〉 4 ½ grains then we put fair water into an open-mouth'd Glass in which we also plac'd the little Bolt-head with oyl of Turpentine and by such a circumposition of salt and snow as is hereafter to be often mention'd we made the water which was contain'd in the wide mouth'd Glasses and by which the Sphaerical part of the Bolt-head containing the Oyl was surrounded we made this water I say begin to freez and when we perceiv'd a little Ice to be produc'd in it we carefully mark'd with a Diamond to what part of the stem the oyl of Turpentine was subsided and then transferring the Bolt-head into a mixture of snow and salt where we kept it for an hour or two till we could perceive it to fall no lower and marking with a Diamond this station also of the Liquor we afterwards remov'd the Glass into a warmer Air till the Oyl by expanding it self had regain'd the highest mark whence it had begun to sink Then into a very little Glass carefully counterpois'd in a pair of exacter scales then the former we gently poured out of the Oyl till what remain'd rested against that mark on the outside of the stem to which it fell when the water began to freez and this we found to amount to somewhat above 9 ½ grains so that for conveniency of reckoning we may safely enough take the Intire number of 10. grains After this we poured out of the remaining oyl into the same little Glass till what rested in the Pipe was even with that mark to which the snow and salt had made it fall and this parcel of oyl hapned to be almost precisely of the same weight with the other so that in this Trial for perhaps in others which it were therefore worth while to make the degree of Cold may much vary the Events the Artificial way of freezing we imploy'd made the oyl subside as much after it had been refrigerated and condens'd by a cold capable of freezing water as that degree of Cold had been able to condense it at first And lastly having deducted the weight of the Glass from the weight of the whole Oyl and Glass to obtain the weight of the oyl alone and having divided the weight of the whole Oyl first by that of the former parcel we have mentioned to be ten grains and then by the superadded weight of the second parcel we took out both which parcels together we estimated at twenty grains we found that rectifi'd oyl of Turpentine of a moderate temper being expos'd to such a degree of Cold as would freez common water did by by shrinking lose but about a ninty fourth part of its Bulk and being reduc'd to as great a degree of Cold as we could bring it to by snow and salt ev'n then it lost but about a forty seventh part of its Bulk I say about because I thought it needless as well as tedious to mind fractions and little odd numbers especially since as we formerly intimated it was scarce possible to arrive at a great exactness in such a Neck as that of our Bolt-head though it were proportionable enough to the Ball and chosen among several that were purposely procur'd for the trying of Experiments 8. There are some other Trials about the Degrees of Cold which for want of Ice and other Accommodations we could not make as we would have done often nor shall scarce be able to do it till more friendly Circumstances afford us an opportunity And yet because our Trials though not prosecuted as far as we thought may possibly prove not unwelcome we will subjoyn something about two of the chiefest of them 9. The one was design'd to measure in what proportion water of a moderate degree of Coldness would be made to shrink by the circumposition of snow and salt before it begin by Congelation to expand it self of this what we shall here take notice is only That by a Trial purposely made with common water in a round Glass furnish'd with a long stem we found the water in that stem to subside so very little that whether or no it were insensible it was inconsiderable But probably a greater Quantity of water and a slenderer stem would have made the shrinking of the Liquor more Notable and upon that Account 't is that I here mention It. 10. The other Thing was to measure by the differing weight and Density of the same portion of water what change was produc'd in it betwixt the hottest time of Summer and first a glaciating Degree of Cold and then the highest we could produce by Art And in order to this we weigh'd with a pair of exact scales a glass bubble heavier then water in that liquor when it seemed to be at a moderate Temper as to Coldness and by the Diminution which we found of the glasses weight in the water we easily collected according to the Rules of the Hydrostaticks the weight of as much water as is equal in bulk to the glass Bubble and thereby the Proportion betwixt the glass and an equal bulk of such water as we first weighed it in then by the application of snow and salt we made that water begin to freez and weighing in it again the same bubble 't was easie to collect by the Decrement of its weight in this refrigerated water what Proportion an equal Bulk of the liquor did then bear to the Glass and by comparing these two differing Proportions together we were assisted to make an Estimate how much the water was made more heavy and dense by the Action of a freezing degree of Cold Afterwards taking our time in Summer we thought fit in the same parcel of water that had been purposely reserved in a glass to weigh the same bubble that by the difference of its weight in the water when
made much lighter by the heat of the ambient Air we might obtain the Information we desir'd to which we shall add That we also recommended to some Virtuosi that were likely to have the opportunity of gratifying Us that such an Experiment might be procured to be made in the midst of Summer in some part of Italy by the help of the there not unfrequent Conveniency of a Conservatory of snow wherein the water might be reduc'd to freez before the end of the same hour at whose beginning the there warmer Air had given it its greatest Expansion and so the Difference betwixt the Density of the same parcel of water might be the more conspicuous But as I have not received any Account of my Desires from abroad so coming now 〈◊〉 home to review the Memorial I caused to be written of the newly mention'd Observation I find that through the Negligence or Mistake of an Amanuensis there must needs be a manifest oversight committed in the 〈◊〉 down the Numbers which my Memory does not now enable me to repair And the season being now improper to repeat the Experiment as well as the numerical parcel of water I had kept and I imployed both times being thrown away I think it may be sufficient if not too much to have thus particularly intimated the way we took without ading the Cautions where with we proceeded nor what Trials we made to the same purpose with high rectifi'd spirit of Wine since unlucky accidents frustrated our Attempts 11. Whether the making of these kind of Trials with the waters of the particular Rivers or Seas men are to sail on may afford any useful estimate if and how much Ships and other Vessels may on those 〈◊〉 be safely loaden more in Winter 〈◊〉 in 〈◊〉 may be an 〈◊〉 of which I shall not in this place 〈◊〉 any 〈◊〉 Notice then to intimate thus much That the difference betwixt water highly refrigerated and that which is but of an usual degree of coldness is not so great as some 〈◊〉 〈◊〉 seem to have thought For on a Day which though made cold by snow intermingled with the rain that then fell was not a frost we took common water and weighed in it a glass Bubble whose weight in the Air was 150. grains and this Bubble weigh'd in that water lost so much of its former weight as to weigh about 28 â… grains and then by snow and salt reducing that water to such a degree of Coldness that it began to be turned into Ice about the inside of a small open glass that contain'd it we found the same Bubble not to weigh at all above one eighth part of a grain less then it did before So that if we may judge of the shrinking and condensation of the water by the Increment of weight it shrunk but about a 230. part of its former Bulk and this according to a pair of scales that would turn with about the 32. part of a grain which may keep us from wondring at what we lately delivered concerning the very inconsiderable subsidence of the water we exposed to snow and salt in a small Bolthead And it may also make that the more probable which we not long since related about the oyl of Turpentines not losing much above a 100. part of its Bulk by being expos'd to such a degree of cold as made water begin to freez Whether we may from this and from the formerly recited Experiment of the great subsidence of spirit of Wine in a seal'd Weather-glass safely conclude these subtile distill'd Liquors to be much more sensible then water of Cold as well as of Heat further Trials will best resolve and these I have not now so much opportunity as I could wish to pursue 12. But they that have a mind to prosecute Experiments of this kind and others that relate to the Degrees of Cold may perchance be somewhat assisted even by these Relations and especially by those Passages that mention the use of the seal'd Weather-glass furnish'd with spirit of Wine and of those wherein a drop of liquor is kept pendulous For the former of these being not subject to the Alterations of the Atmospheres 〈◊〉 nor as may be probably suppos'd by reason of the strength of the high rectifi'd spirit of Wine to be frozen by sending the same Weather-glass which may be made portable enough as I have tried by transporting one of them in a Case that might be easily carri'd even in a Pocket from one Countrey to another one may make far better Discoveries of the differing Degrees of Coldness in differing Regions and know somewhat near how much the Air even of Muscovy or Norway or Greenland it self is colder then that of England or any other Countrey whence the Weather-glass shall be sent The Instrument being accompanied with a memorial of the Degree it stood at when expos'd to such a Cold as made water begin to freez 13. The other Thermometer where a drop of liquor is kept pendulous may not only be imploy'd in such cases where the Pipe and Bubble can be erected upon the Horizon but by reason that the outward Air will indifferently impel the Bubble laterally or upwards upon the Refrigeration of the inward and that the bubble will not barely by its weight drop out of the inverted Instrument because of the resistence of the subjacent outward Air for these causes I say such a Thermoscope may as we have tri'd be also us'd where the Pipe shall be held Horizontal or inclin'd or even Perpendicularly downwards so that the flat Part of the Bubble may be appli'd to discover the Coldness either of the Wall or of the Ceiling of a room or other Bodies however scituated And if the Pipe be made long and even as sometimes we imploy one above a foot long not only sensible but great Effects of very little Disparities in the Coldness of Bodies to which the Instrument is appli'd may with pleasure be observed And the same drop of liquor may be long enough preserv'd useful in the Pipe But this Advertisement I shall give that as sensible as this Instrument appears to be of the nicer Differences of Coldness as of Heat yet they that shall have the Curiosity to examine with it as I have done the Temperature I say not of more resembling Bodies but of Liquors that may be thought to have their parts so differingly agitated as common Water high rectifi'd spirit of Wine and even rectifi'd oyl of Turpentine I add not Dephlegm'd oyl of Vitriol because of some odd Phaenomena not here to be insisted on will perhaps find the Event so little in many cases answer the Expectation he would have had of uniformly finding great Disparities in their actual Coldness if he had not met with this Advertisement that he will not much wonder that a Person who wants not other Imployments for his Time was willing to decline so tedious and nice a Task Title V. Experiments touching the Tendency of Cold Upwards
frozen whereas the other Egg that lay by upon the dry table had not only its whole white frozen into a consistent Body but the Yelk it self though we saw no distinct particles of Ice in it was grown so hard that it cut just like the Yelk of an Egg over boiled and being cut quite through shewed us certain concentrical circles of somewhat differing Colours with a speck much whiter then any of them in the middle of the Yelk which last circumstances whether they were accidental or no further observation must determine Note that though we have not found above once that frozen Eggs would swim yet when we had broken such Eggs the frozen white would swim but not the yelk 4. We afterwards repeated the Experiment of laying two frozen Eggs near together in the place above mentioned the one under water and the other out of it till that put in water had got a thick Icy crust and by breaking of them both presently after one another were confirmed in the Perswasion that frozen Eggs will thaw by great odds caeteris paribus faster when immersed in water then when surrounded only with Air. 5. We likewise took a frozen Egg and from a fix'd place suspended it so by a slender packthread that it hung quite under water without yet touching the vessel that the water was in This we did partly upon another Design and partly to observe whether or no the Ice would in this case be considerably thicker or thinner against the lower parts of the Egg as we formerly mention'd our selves to have observed it to be very manifestly at the lower parts of a glass which having Ice and Salt in it was immersed under water but when we took out the Egg after we saw that its Icy case had covered the packthread it was hung by we found the case upon breaking it of a thickness uniform enough to keep us from concluding any thing from this trial since though there were a pretty deal of Ice generated at so small a distance from the case of the Egg that it seemed to owe its Production to the same cause yet which was somewhat odd we did not find that this Ice stuck to that which did immediately embrace the Egg though we had some faint suspition that the Rudiments of it might have been very early parted from the Egg by some little shaking of the table occasioned by peoples passing to and fro in the room 6. We took some Pippins and exposing them to freez all night and putting them the next morning into a Bason of very cold water though in a warm room they were not long there without being inclosed with cases of Ice of a considerable thickness Where note 1. That that part of a floating Apple that was immersed under water had a very much thicker coat then the other part which remained above it 2. That the extant part seemed likewise to be harder then the immersed 3. That one of these Pippins being purposely left out of the Bason but layed by it seemed upon cutting to be harder and more frozen then those Apples which had been put into the water which scarce seemed to be at all harder then ordinary Pippins that had never been set to freez at least as to those parts of the Apples that were near the rinde and consequently near the Ice 4. That neither frozen Pippins nor frozen Eggs notwithstanding their great power of turning part of the contiguous water into Ice did appear to Us to detain or congeal any of the roving vapors of the Air as Ice or Snow included with Salt in glasses is as we have formerly observed accustomed very remarkably to do 7. We took Eggs and froze them with ice and salt till the shells of them were made to crack then we took them out and put one of them in Milk two of them in a wide Drinking Glass full of Beer and two more in a large Glass wherein we covered them with Sack that was poured in till it reached much higher in the Glass then the Eggs. But none of these trials produc'd as we could perceive one grain of ice And being desirous to see whether the Acid salt of Vinegre or the Cold in a well frozen Egg would have the chief Operation if those two Bodies were put together I found upon Trial that the Saline parts of the Vinegre began to dissolve the Egg-shell as appeared by the much altered Colour of it but the Cold of the ice in the Eggs was not able to freez any part of the water or phlegm of the Vinegre 8. We had also thoughts of trying whether or no pieces of Iron of several shapes and bignesses being for divers days and nights exposed to the freezing Air and afterwards immersed in water would produce any ice as frozen Eggs and Apples do For the Brittleness of the Laths of Stone-Bows in sharp frosts together with other observations elsewhere mention'd seem to argue that to use a popular phrase the Frost does also get into these Bodies And I have been assured by one whom the Trials I had made with Eggs and Apples invited me to consult that a great Cheese he immersed in water in a Cold Countrey was presently covered over with ice But though as I said I had thoughts of making the above mentioned Trials yet for want of a frost sufficiently durable I was not able to effect what I design'd But thus much I tri'd That though I kept good Lumps of Iron and as I remember of other Metalls besides pieces of Glass and a stone or two of a convenient size in snow and salt I know not how much longer then would have suffic'd to make Eggs or Apples or such kind of things fit to produce store of ice in water upon their being thaw'd therein yet we could not find that upon the immersing the several newly nam'd Mineral Bodies there was the least ice produced in the cold water where we kept them covered I must not nevertheless omit to make some mention of that which lately 〈◊〉 to happen at the door of our own Laboratory respecting the North East where some Glasses newly brought from the shop and not imployed lying in a Basket as they poured water into one of them to rince it part of it was presently turned into ice whilest one of my Domesticks held it in his hand who coming presently to show it me I suspected the ice might have come from or rather with the water that was poured into the Glass but upon enquiring was assured of the Contrary 9. But here I must not omit another trial relating to the former Experiments which may seem somewhat odd if its Event prove constantly the same as when we tried it For after these and divers other Experiments made with frozen Eggs and Apples we thought it might be worth the examining whether or no Ice and the Liquors of these Concretes would produce the like effects as Frozen Eggs and Apples and because 't is usually an easier
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
fain to measure their Time by hour-glasses For though this odd Effect might be suspected to proceed from some little Isicles sticking to some of the Wheels or the Line in regard they not far off tell us that the steams of their Bodies and other things within their close house did so fasten themselves to the walls to the Roof and even to their Cabins as to line them with Ice of no less then two fingers thick yet besides that it cannot be probably suppos'd that they who had so great need of their Clock during the tedious absence of the Sun for many weeks together should not all the Winter long be aware of this Besides this I say I find that in Captain James's wintering at Charleton his Clock and Watch were so frozen too That they could not go notwithstanding they were still kept by the fire side in a Chest 〈◊〉 in clothes So that in case it appear that according to what we 〈◊〉 noted out of Wormius the frost can get into Metals it can also distend them and other stable Bodies We might conceive that the stopping of the Clocks might proceed from the stiffness or the swelling of the line to which the weight was fastned or a swelling even of some of the wheels or other Metalline parts of the Clock that may spoil the necessary congruity between the Teeth c. as I have tri'd that some parts of an Iron Instrument I caus'd to be made would by no means fit one within another when expanded by much Heat and though Cold be the cause of the expansion the Effect may be the same though at other times they would And if we knew whether Springs lose any thing of their Elasticity by the violence of the Cold we might thence also be assisted to guess whether the frosts Operation upon the Spring of Captain James's Watch for he mentions that as distinct from his Clock might contribute any thing to the forcing it to stand still But these are bare Conjectures from which I will therefore pass on to the following Section Title VIII Experiments touching the Contraction of Liquors by Cold. 1. BUt notwithstanding all the former Experiments we must not conclude universally that all liquors are dispos'd to be expanded by Cold neither by a moderate degree nor even by so intense a degree of it as suffices to freez or congeal the liquors exposed to it this we have tri'd not only in spirit of Wine Aqua fortis Oyl of Turpentine and divers other liquors that we could not bring to freez but also in oyl congeal'd by the Vehemence of Cold so that as to the change of Dimensions produc'd in Liquors by Cold there must be a great difference allowed betwixt water and aqueous liquors on the one side and oyl and divers other liquors that are some of them of an oleaginous and some of a very spirituous or a very highly corrosive nature on the other side Nor have we yet made trials enough to reduce this matter to a certainty For though we could not bring some strong Saline spirits nor the most of Chymical oyls to freez yet in some our Attempts succeeded not ill But I remember not that in any liquor we could by Cold produce any sensible expansion but rather a manifest Condensation unless we could bring it actually to freez 2. The trials we made of the Efficacy of Cold to condense liquors were many but it may for the present suffice to set down two or three differing ones that occur to us in our Collections To the entry of the Experiment lately recited of the expansion of Milk Urine and the Rhenish Wine there are subjoyned these words But the Egg that held the spirit of Wine though it were much smaller then we usually employ and fitted with a proportionably slender stem and though it were kept divers hours partly in Ice and Salt and partly in Snow and Salt yet it froze not at all but subsided by degrees below the first mark to the quantity of ¾ of an inch in the stem and though it afterwards seemed to rise a little yet it never swelled up again to the said first mark 3. We took a round Bolthead of about in Diameter and poured in Mercury till it reached a pretty way into the neck which was purposely drawn more slender then ordinary and having without approaching it to the fire freed it from some of the larger bubbles of Air that appeared at the sides we put it into a mixture of Ice and Salt where the Cold so wrought upon it that watching it attentively we could discern not only its having moved but its motion downwards which it continued though not visibly in the progress as at the first till it was subsided in the neck two inches or better which was far more then could be attributed to the contraction of any sensible Aerial Particles though they had lost not only the 30. part of their Dimensions as we have sometimes observed of the Air but had been contracted to a point and we observed too that the Quicksilver once thus infrigidated though not frozen retained some of the acquired Cold for many hours after as appeared by its keeping below the mark of its first height though we had kept it all night in a warm room 4. We took a small Egg with a proportionably slender stem into which we poured common oyl till it rose a pretty way but not much above the oval part of the glass then having put a mark upon the station of the liquor we placed the vessel in snow and salt and observed it not to swell as other liquors but to subside with Cold till being quite frozen or congeal'd it appeared to be shrunk about an inch or more beneath the mark then being thaw'd it swelled again to the mark 5. The Experiment was repeated the second time with not much worse success but we found that if the glass were removed out of the snow into some place near the fire the hot Air would not only thaw it but so rarifie it as to make it ascend above the mark A third time we seal'd up the same oyl in the same glass and repeated the Experiment with like success to that we had the second time and that the frozen oyl was really condensed we found because it would sink in oyl of the same kind cold but unfrozen and this notwithstanding divers bubbles which we observed usually to be made about each lump of congeal'd oyl that we cast in upon its begining to sink in the fluid oyl This we tri'd both with oyl well congeal'd or if another word please better Incrassated or Curled by snow and salt and with oyl less congeal'd frozen by the bare cold of the Ambient Air but this latter seemed to sight to sink more slowly then the other as being less congealed and ponderous yet would not lumps of the mass of oyl sink or continue immersed I say not in common water but in Sack or
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
the Bubbles wont to abound in Ice be filled with common Air and even this question though it seem but one comprizes two for to resolve it we must determine whether there be any true Air contained in those Cavities and whether in case there be they be adequately filled with that Air by true Air I mean such an invisible fluid as does permanently retain a spring like the common Air. 7. The former of these two Questions I must confess my self not yet resolved about my Experiments having not hitherto succeeded uniformly enough to satisfie so jealous an observer But yet I shall annex our trials not only because the thing has not been that we know of somuch as attempted by others and our ways of Experimenting if they be duly prosecuted seem as promising and hopeful if the Question be reducible to any certain Decision as perhaps will be easily lighted on but because also we have if we mistake not resolved the second Question by shewing that there is but a small part of true Air contained in the Bubbles of Ice whatever Ingenious men that rely upon probable Conjectures without consulting Experience have been pleas'd to believe to the contrary That the bubbles observed in Ice cannot all be filled with the Aerial particles lurking in the water seems evident enough by the expansion of the water and the Quantity of space taken up by those bubbles which how the interspers'd and formerly latitant Air can adequately fill unless the same parcel of Matter could truly 〈◊〉 much more space at one time then at another which I take to be physically impossible I do not yet apprehend But two ways of trial there are which we imployed to shew that the Icy bubbles are nothing near filled with true Air whether Men will have that pre-existent in the water or stollen in from without or generated anew the former of the two ways of trials probably arguing that these bubbles proceed not only for that they may proceed partly we do not at all deny from the Air pre-existent in the water and the latter concluding more generally that but a small part of the icy bubbles are filled with genuine Air. 8. And 1. we were invited to conjecture both that sometimes or in some cases the Air latitant in the water might contribute to generate icy bubbles though it was unable adequately to fill them and again that sometimes or in other cases such bubbles would be almost as numerously generated notwithstanding the recess of far the greatest part of that latitant Air by the three following Experiments taken verbatim out of our Collections I. We took fair water and having kept it in the exhausted Receiver of our Pneumatical Engine for a good while till we perceived it not to send up any more bubbles we presently transferred it into snow and salt where it was long enough before it began to freez and then we observed that the water did not swell near so much as common water is wont to do and the ice seemed to have few or no bubbles worth taking notice of but when I afterwards placed it between my Eye and the vigorous flame of a Candle I could perceive that it was not quite destitute of bubbles though they were extremely small in comparison of those that would probably have appeared in ordinary water Thus far the first Experiment the second follows which was made at another time II. The water that had been freed from the bubbles in the Receiver though it afforded an ice that seem'd to have smaller bubbles yet this ice being thaw'd part of the water was gently poured into a pipe of glass wherein being frozen it swell'd considerably enough above its first level and besides burst the glass being also very opacous by reason of the bubbles The third Experiment was more industriously prosecuted as may appear by this ample Narrative of it transcribed out of our Collections III. We took a small Egg with a pretty long neck and pouring in water till it reach'd an inch within the stem conveyed it into a long slender Cylindrical Receiver provided on purpose to make trials with such tall glasses the Air being by degrees drawn out of the bubbles appeared from time to time greater and greater and when the Receiver was well exhausted the water seemed to boil a longer time then one would have expected and sometimes the bubbles ascended so fast and great that we were in doubt whether the water did not boil over the top of the Pipe the exhausted Receiver was permitted to be so for a good while till the water had discharged it self in bubbles of its Air and then the glass-Egg was removed into a vessel furnished with ice and salt and there left ten or twelve hours that all the water save that in the neck might be throughly frozen and then we found it to have risen a great way above its first height and removing it into an Air temper'd like that wherein the first part of the Experiment was made having left it there in a quiet place for ten or twelve hours to thaw leisurely lest too warm an Air or too much stirring the glass might be an occasion of generating new bubbles in the exterior part of the ice near the glass we saw pretty store of bubbles but when that was thaw'd the rest of the ice appeared of a peculiar and unusual texture having no determinate bubbles that I could easily distinguish but seeming almost like a piece of frosted glass where the Parts that made the Asperity were exceeding thick set but this ice swam in the water whereinto the rest had been dissolved before it was all thawed when there yet remained a lump about the bigness of a small Walnut we reconveyed it into the Receiver to try whether upon the exuction of the Air the ice would be presently melted but the alteration produced was so small if any that we durst not ground any thing upon it The Receiver being exhausted there did at length appear some bubbles in the water but they were not numerous and a hundred of them seem'd not to amount to one of those larger ones the same water had yielded us the first time it was put in in the ice also some small bubbles disclosed themselves which we did not perceive there before wherefore we took out the Egg and found the ice being now thaw'd that the water was subsided to the mark we had made before it was expos'd to congelation if not some very little way beneath it Then we went about to find the Proportion wherein this dispirited water was expanded by glaciation but in pursuing this there hapned a mischance to the glass which kept the Experiment from being so accurate as we designed And therefore though it seemed to us that it amounted to about the twelfth part which is less then that of the undispirited water yet we designed the repetition of the Experiment Only in this we could not be mistaken that the
inverting the stem and breaking the Neb under water we found about ten inches of water to have been impell'd into the stem so that in this there seem'd no generation of Air. 17. To all these Experiments we shall subjoyn in two words that as in water so in some aqueous liquors we found that the icy Bubbles were not fill'd with Air though we did not think fit to take the pains to measure their respective Expansions by being congeal'd For in that elsewhere mention'd Experiment where we expos'd Milk Urine and Rhenish-wine to freez when all those liquors were risen above their former marks as is there related our Notes inform us that the Experiment was thus prosecuted 18. Being seal'd up the foregoing words mention'd the above-named expanded liquors and suffer'd to thaw the several liquors subsided to their first marks or thereabouts and the glasses being inverted and broken under water we were by an accident hindred from observing what we desir'd in that which had the Wine though when it was taken out of the freezing pot it had ice but not much swimming in it But into the glass that had the Milk the water was manifestly impell'd by the outward Air and so it was into the glass that had the Urine which being remov'd from the Bason and reinverted appear'd to have as much new liquor in its stem as amounted by guess to five or six inches 19. To which Experiment we may add that another time a seal'd glass of partly frozen Claret-wine being broken under water the water was impell'd up between half an inch and an inch above the mark beyond which it would not have ascended if the bubbles had been full of true and permanent Air. 20. If it be said that though I have delivered too many Particulars about so empty and slight a Theme as Bubbles I have this to answer that possibly all these Experiments have rather shew'd us what it is not that fills them then what it is so that more then all these Experiments appearing requisite to clear up the Difficulties about them I shall not think I have altogether mis-spent my time especially if so many past Experiments both new and not altogether impertinent by their not having taught us enough about so despicable a subject as a Bubble shall as they justly may teach us Humility Title X. Experiments about the Measure of the Expansion and the Contraction of Liquors by Cold. 1. TO the Experiments mention'd in the Seventh and Ninth Titles which shew that water has an Expansion it will be proper to subjoyn some of those whereby we endeavoured to measure that Expansion And here we shall not content our selves to say that whereas the Authors we had formerly occasion to point at take notice of their having raised water in a Bolthead half an inch or an inch by freezing we have made it ascend a foot and a half and more This I say we shall pass by because that though by such Experiments we have very clearly and undeniably manifested the Expansion of the water yet unless the Capacity of the vessel be known they will signifie but little towards the determining the Quantity of that Expansion which yet is the thing we are now enquiring after wherefore we shall add that we employ'd two differing ways to measure this Expansion 2. The one was by putting in by weight such a number of ounces of water into a Bolthead till the water was risen a pretty way in the long stem wherewith it was filled then marking on the outside to what height every freshly added ounce of water reach'd in the stem we afterwards poured out a convenient Quantity of the liquor yet leaving enough to fill the whole cavity of the spherical or obtuse end of the vessel and of the lower part of the stem then leisurely freezing this remaining water from the bottom upwards we observed that when it was frozen the ice that was made of 82. parts of water filled as one of our Notes inform us the space of 91. and if I mistake not the Character an eight so that by this troublesome way of Examination we found that the water by the Expansion it received from Cold was made to possess about a ninth part more space then it did before congelation 3. In another of our notes we find as follows 55 parts of water extended themselves by freezing into sixty and a half about six of those parts remaining unfrozen so that in this Experiment the waters Expansion was not much though somewhat differing from what it was in that last mention'd 4. The other way we made use of to measure the Dimensions that water gains by freezing was to take a Cylindrical pipe of glass seal'd at one end and left open at the other at which we fill'd it with water to a certain height that we took notice of by a mark appli'd to the outside and then keeping it in an erected posture and freezing it from the bottom upwards we found that it had acquir'd by a tenth part or thereabouts greater Dimensions in the form of ice then it possessed in the form of water But the nature of the particular parcel of liquor exposed to the Cold for it is not necessary that all waters should be equally dispos'd to be expanded by freezing and some other circumstances not now to be discoursed of may well beget some little variety in the success of this sort of trials For in one that we made carefully we found the Expansion somewhat greater then that last mentioned as may appear by the following Note which compar'd with what was lately delivered of the trials we made by weight of the water's Expansion may invite us to think that we cannot much err by estimating in general that the room that Ice takes up more then water amounts to about a ninth part of the space possessed by the same water before it was turned into Ice The note we were speaking of is this 5. In a more then ordinarily even Cylindrical glass we exposed some water to freez to measure its Intumescence and found that it expanded its self to about an eighth part or at least a ninth upon glaciation this we tri'd twice and thought that the Intumescence might have been more considerable but that in a Cylinder the freezing did not seem to succeed so well But here we must resolve a difficulty which though ordinary Readers may take no notice of yet may breed a scruple in the minds of those that are acquainted with Hydrostaticks For to such Readers this Account of ours may seem to be contrary to the Experience of Navigators into cold Climates who tell us as we shall have occasion to take notice in due place of vast pieces of Ice as high not only as the Poops of their Ships but as the Masts of them and yet the Depth of these stupendious pieces of Ice seems not at all Answerable to what it may be suppos'd to be in case we compare together the
Estimate above deliver'd of the Expansion of water and that grand Hydrostatical Theorem demonstrated by Archimedes and Stevinus That floating Bodies will so far and but so far sink in the Liquor that supports them till the immersed part of the Body be equal to a Bulk of water weighing as much as the whole Body For Captain James in his often cited Voyage makes mention of great pieces of Ice that were twice as high as the Top-mast-head of his Ship 6. And the Hollanders in their famous Voyage to Nova Zembla mention one stupendious Hill of Ice which I therefore take notice of here not only because it has been thought the greatest that men have met with but because they deliver its Dimensions not as Captain James and Navigators are wont to do by comparison with the unknown heights of some of the Masts of their Ships but by certain and determinate Measures which in the Icy Island we are speaking of were so divided by the surface of the water that there was 16. fathome extant above it though there were but 36. beneath it which though a vast depth in it self yet 〈◊〉 but little exceed double the height And the Danish Navigator Janus Munckius imploy'd by his King to bring him an Account of Greenland mentions some floating pieces of Ice that he met with and observ'd in that Sea which though but somewhat above 40. fathome under water were extant 20. fathome that is near half as much above water whereas it seems that according to our above mention'd Computation of the Expansion of water the part under the water ought to be eight or nine times as deep as that above the water is high 7. To clear this difficulty I shall represent these three particulars First that in our Computation the Ice that sinks so deep is suppos'd to float in fresh water whereas in the Observations of the above nam'd Navigators those vast pieces of Ice floated on the Sea-water which by reason of its saltness being heavier then fresh-water Ice will not sink so deep into that as into this And that salt may hugely increase the weight of the water wherein it is dissolv'd may be clearly gather'd from the ponderousness of common Brine and from the practise of several sorts of Tradesmen who to examine the strength of their Lixiviums and other Saline Liquors are wont to try whether they will keep an Egg floating which we know common water will not do And I have also by the Resolution of some Metalline Bodies in fit Menstruums made Liquors that are yet much more ponderous then is sufficient for the support of Eggs. But yet we must be so candid as to take notice of what some Modern Geographers deliver with probability enough namely That nearer the poles the Seas are not wont to be so salt as in the temperate and the Torrid Zones and those Northern being not so salt as our Seas there is the less to be allow'd for the difference in gravity and consequently in the power to keep Ice from sinking betwixt those Seas and ours 8. But secondly this lesser saltness of the water in the Northern Seas may as to our case be recompenc'd by the greater coldness of it For though as we have formerly observed the Condensation of fresh water effected here by a degree of Cold capable to make it begin to freez is not so great as most men would imagine yet besides that I have often taken pleasure to make the same Body to sink or ascend in the same water by a much less variation 〈◊〉 Cold then that we have been mentioning it is to be consider'd that the degree of Cold to which water was brought in the Experiment deliver'd in the fourth Section to which we are now looking back was but such a degree as would make fresh water begin to freez whereas the salt Sea-water being indispos'd to congelation may by so vehement a Cold as reigns in the Winter season in those gelid Climates be far more intensly refrigerated and thereby more condens'd then common water is here by such a measure of Cold as may begin to freez small portions of it But though what we have hitherto represented may well be look'd upon as not inconsiderable to the purpose for which it has been alledg'd yet the main thing that is to remove the scruple suggested by the height of Icy hills above the water is 9. Thirdly that such Hills of Ice are not to be look'd upon as intire and solid ones but as vast piles or lumps and masses of Ice casually and rudely heap'd up and cemented by the excessive Cold freezing them together by the intervention of the water that washes them which piles of many pieces of Ice are not made without great Cavities intercepted and fill'd only with Air between the more solid Cakes or Lumps so that the weight of these stupendious pieces of Ice is not to be estimated by the bigness they appear of at a distance from the Eye but considering how much Air there is intercepted between the Icy Bodies of which they are compiled there may be a hollow structure of Ice reaching high into the Air and yet the whole Aggregate or Icy pile will press the subjacent water on which it leans no more then would as much water as were equal in Bulk only to the immers'd parts as we see in Barges loaden with Boards which though pil'd up to a great height above the water make not the vessel to sink more then a Lading that would make a far less show and oftentimes be all contain'd within the Cavity of the vessel provided it be more ponderous in specie But to enter into any further Consideration of these Hydrostatical matters would be improper in this place especially since we have elsewhere treated of them And that these floating Hills and Islands of Ice are not intire and solid pieces of it we shall otherwhere have occasion to shew out of Navigators and even in the Observation we have mentioned out of Janus Munck the Learned Relator of it Bartholinus takes notice that those vast pieces of Ice we have been mentioning that reach'd 20 fathome above water were compiled of store of Snow frozen together 10. These Considerations may serve to render some Account of those stupendiously tall pieces of ice whose extant part bears so great a proportion to the immersed part when the whole mass does really float But I confess I doubt that not only in the Examples we have alledg'd but in other eminent ones of mountains of ice if I may so call them there may be a mistake and that the height of them above the water would be far less and the depth under water far greater if the ice had water enough to swim freely For Sea-men by reason of the difficulty are not wont to measure the height of those pieces that float at liberty in the Sea And as for those that are on ground as their heights lye far more convenient
to be measured so the measurers not knowing how long they may have been on ground for ought I know much of that admir'd height may be attributed to the snows that from time to time fall very plentifully in those frozen Regions and are compacted together either by the Sun whose Beams sometimes begin to thaw it and sometimes by the water of the waves that beat against the Ice and being congeal'd with the snow does as it were cement the parts of it together and sometimes by both of these causes So in the instance alledg'd out of Captain James of pieces of ice that were twice as high as his Top-mast-head it is said also that they were on ground in 40. fathome And in the other Example mention'd out of Bartholinus though there be 40. fathome attributed to the immersed part of the ice yet that measure is not exclusive of a greater for it is said that the ice reach'd downwards above 40. fathome and how much downwards and whether as far as the ground we are left at liberty to guess And in that stupendious piece of Ice recorded in the Nova Zembla voyage to have been in all 52. fathome that is 300. and twelve foot deep though it be granted what they affirm that it was 16. fathome above the water which is almost a third part of the whole depth yet I observe that of this Icy mountain it is said that it lay fast on the ground So that as on the one side it seems probable that the upper part of Islands of ice may be increas'd by snow and as I remember that in that famously inquisitive Navigator Mr. Hudsons voyage for the discovery of the North-west passage 't is related that his company was so well acquainted with the Ice that when Night or foggy or foul weather took them they would seek out the Broadest Islands of Ice and there come to Anchor and run and sport and fill water that stood the Ice in ponds very fresh and good So on the other side we know not how much lower the Dutch-mens Ice and Captain James's would have reach'd into the Sea in case the ground they rested on had not hindred them For though one might probably think that these are the greatest depths that any Hills of Ice have been observ'd to attain that mention'd by the Hollanders reaching 36. fathome beneath the water and that mention'd by Captain James no less then 40. fathome yet I find in Mr. Hudsons Voyage that the English in the Bay that bears his Name met with more then one or two Islands of Ice of a fargreater depth underwater For among other things the Relator has this memorable passage In this Bay where we were thus troubled with Ice we saw many of those mountains of Ice a ground in six or seven score fathome water And if the Sea had been deep enough even these stupendious moles of Ice would probably have sunk much lower and so have lessened the heights of the mountains 11. I know that delivering the measure of the Expansion of water alone I have not said all that may be said about the Expansion of Liquors But because as it has not yet appeared to me that any Liquor is expanded by Cold unless by actual freezing I doubted whether Aqueous Liquors as Wine Milk Urine c. were otherwise expanded by congelation then upon the Account of the water or phlegmatick and in a strict sense congealable part contain'd in them and whether it were worth while for a man in haste to examine their particular Expansions Notwithstanding which I would not discourage any from trying whether or no by the differing Dilatations of Aqueous Liquors some of them of the same and some of them of differing kinds we may be assisted to make any estimate of the differing proportions they contain of phlegm and of more spirituous or useful Ingredients 12. After what has been hitherto delivered concerning the Expansion of Liquors by Cold it may be expected we should say something of the measure of their Contraction by the same Quality But as for water which is the principal Liquor whose Dimensions are to be consider'd I have formerly declar'd that I could seldom or never find its contraction in the Winter season when I tried it to be at all considerable And I shall now add that having for greater certainty procur'd the Experiment to be made by another also in a Bolthead the Account I received of it was that he could scarce discern the water in the stem to fall beneath its station mark'd at the upper part of the pipe when the water in the Ball was so far infrigidated as to begin to freez Though I will not deny that in warmer Climates as Italy or Spain the contraction of the water a little before glaciation begins may be somewhat considerable especially if the Experiment be made in Summer or in case either there or here the water expos'd to freez be put into a vessel very advantageously shap'd or brought out of some warm Chamber or other place where the heat of the Air that surrounded it had rarifi'd it But to examine the measures of Contraction in the several Liquors and with the nice Observations that such a work to be accurately prosecured would require would have taken up much more of my time then I was willing to imploy about a work which I look'd not on as important enough to deserve it And therefore I shall here add nothing to what I have said under the Title of the Degrees of Cold touching the contraction of spirit of Wine and of oyl of Turpentine by the differing degrees of that Quality And as for the condensation of Air the vastest fluid we deal with I did indeed think fit to measure how much Cold condenses it But the account of that Experiment will be more opportunely deliver'd in one of the following Discourses Title XI Experiments touching the Expansive Force of Freezing Water 1. HAving shewn that there is an Expansion made of water and Aqueous Bodies by Congelation let us now examine how strong this Expansion is and the rather because no body has yet that we know of made any particular trials on purpose to make discoveries in this matter so that although some unhappy Accidents have kept our Experiments from being as accurate as we designed and as God assisting we may hereafter make them yet at least we shall shew this Expansion to be more forcible then has hitherto been commonly taken notice of and assist men to make a somewhat less uncertain Estimate of the force of it then they seem to have yet endeavoured to enable themselves to make 2. And 1. we shall mention some Experiments that do in general shew that the Expansion of freezing water is considerably strong We took a new Pewter-bottle capable to contain as we guess'd about half a pint of water and having fill'd it top full with that Liquor we scru'd on the stopple and exposed it during
a very frosty night to the cold Air and the next morning the water appeared to have burst the Bottle though its matter were metalline and though purposely for this trial we had chosen it quite new the crack appeared to be in the very substance of the Pewter This Experiment we repeated and 't was one of those bottles fill'd with Ice that had crack'd it which a Noble Virtuoso would needs make me who should else have scrupled to amuse with such a Triffle so great a Monarch and so great a Virtuoso bring to his Majesty to satisfie him by the wideness of the crack and the Protuberance of the Ice that shewed it self in it that the water had been really expanded by Congelation 3. We also tried whether or no a much smaller Quantity of water would not if frozen have the like Effect and accordingly filling with about an ounce of water a scru'd Pewter box such as many use to keep Treacle Salves in quite new and of a considerable thickness we found that upon the freezing of the included water the vessel was very much burst Afterwards filling a Quart Bottle if I mistake not the capacity with a congealable liquor and tying down the Cork very hard with strong Packthread we found that the frost made the liquor force out the stopple in spite of all the care we had taken to keep it down But afterwards we so well fastned a Cork to the neck of a quart bottle of Glass that it was easier for the congealing liquor to break the vessel then to thrust out the stopple and having for a great many hours expos'd this to an exceeding sharp Air we found at length the bottle burst although it were so thick and strong that we were invited to measure the breadth of the sides and found that the thinnest place where it was broken by the Ice was 3 16 of an inch and the thickest ⅜ that is twice as much 〈◊〉 we also by the help of the frost broke an earthen bottle of strong Flanders metal of which the thinnest part that was broken was equal by measure to the thinnest part of the other 4. But the above mention'd Instances serving only to declare in general that the Expansion of water by Cold is very forcible I thought fit to attempt the reducing of the Matter somewhat nearer an Estimate less remote from being determinate and because the water expos'd to congelation may be probably supposed to be Homogeneous we judg'd that the quantity of it may very much vary its degree of Force and because some may suspect that the Figure also may not be inconsiderable in this matter we thought fit to make our Trials in a Brass vessel whose Cavity was Cylindrical and which to make it stronger had an orifice but at one of its ends and whose thickness was such that we had reason to expect that whilest the top remained covered but with a reasonable weight the included water would find it more easie to lift up that weight then break the sides To this Cylinder we fitted a cover of the same mettal that was flat and went a little way into the Cavity leaning also upon the edges of the sides for the more closer stopping of the orifice the cavity of this Cylinder was in length about five inches and in breadth about an inch and three quarters This Cylinder being fill'd top full with water and the cover being carefully put on was fastned into an Iron frame that held it erected and allowed us to place an iron weight amounting to 56. pound or half a hundred of common English weight which circumstance I mention because the common hundred that our Carriers c. use exceeds five score by twelve But this vessel being exposed in a frosty night to the cold Air the contain'd water did not the next morning appear to be frozen and the trial was another time that way repeated with no better success as if either the thickness or clearness of the mettal had broken the violence of the external Airs frigefactive Power or the weight that oppressed the Cover had hindred that Expansion of the water which is wont to accompany its Glaciation Wherefore we thought it requisite to apply to the outside of the vessel a mixture of salt with ice or snow as that which we had observed to introduce a higher degree of Cold then the Air alone even in very frosty nights and though this way it self the glaciation proceeded very slowly and sometimes scarce at all yet at length we found that the water was by this means brought so far to freez that on the morrow the ice had on one side swelled above the top of the Cylinder and by lifting the cover on that side had thrown down the incumbent weight but in this trial the cover having been uniformly or every where lifted up above the upper orifice of the Cylinder we repeated the Experiment divers times as we could get opportunity sometimes with success and sometimes without it and of one of the chief of our Experiments of this sort we find the following account among our Collections 5. The hollow brass weight being about one inch and thee quarters in Diameter and the brass cover put on was loaded with a weight of 56. pound upon the cover and expos'd to an excessively sharp night the next morning the cover and the weight were found visibly lifted up though not above that we could discern a small Barley-corns breadth but the thickness of the brass cover was not here estimated which was much less then half an inch which according to former observations one might exspect to see the ice ascend But that which we took particular notice of was that the inclosed Cylinder of ice being by a gentle thaw of the superficial parts taken out appear'd so full of bubbles as to be thereby made opacous Also when in the morning the Cylinder was brought into my Chamber before the fire was made the 56. pound weight being newly taken off at a little hole that seemed to be between the edge of the Brass and Ice there came out a great many drops of water dilated into numerous bubbles and reduced into a kind of sroth as if upon the removal of the oppressing weight the bubbles of the water had got liberty to expand themselves but this lasted but a very little 6. After this the difficulty we have often met with in the placing of great weights conveniently upon the cover of a Cylinder and the Expectation we had to find the Quantity of the water we made use of capable upon its Congelation to lift up a much greater weight invited us to make trial of its Expansive force by some what a differing way which was to fit a wooden plug to the Cavity of the Cylinder after we had suffered it to soak a convenient time in water that swelling as much as it would before it might be made to swell no more by the water which would lye contiguous
to it in the vessel and then to drive it forcibly in till by considerable weights appended to the extant part of the plug when the Cylinder was inverted we could not draw it out the success of one of these Trials is thus set down in our Collections 7. A Plug was driven into the Cavity of a Brass Cylinder first filled with water the Plug being also well soaked then the Cylinder being inverted the Plug took up half a hundred and a quarter of a hundred weight and would possibly have taken up much more and being exposed to a very sharp night the freezing water thrust out the plug about a barley-corns breadth quite round above the upper edge of the Cylinder and it freezing all that day and the next night it was again exposed the plug not being yet taken out and then the plug was beaten out a little more namely in all near a quarter of an inch 8. Thus we see that the expansive endeavour of the water forced a resistence at least equal to that which would have been made by a weight of 74. pound and probably as the note intimates would have appear'd able to do more if we had had convenient weights and Instruments wherewith to have measur'd the strength of the waters endeavour outwards which some subsequent Trials made us think very considerable though not finding their Events set down in our notes we think it fit at present to leave them unmentioned But one thing there is in these trials that I think not unworthy a Philosophers notice and his considering namely that this endeavour of the water to expand it self is thus vigorous though the uttermost term to which it would expand it self in case it were not at all resisted would be but to about a ninth or at most an eight part of the space it possest before it began to freez whereas Air may by Heat which yet we have elsewhere shewn will not reduce it to any thing near its utmost expansion be brought to possess though not to fill according to the diligent Mersennus's observation seventy times the Dimensions it had before Rarefaction and consequently the Air expanded by Heat does by its endeavours tend to acquire above 60. times the space that the water does when expanded by so high a degree of Cold as is capable to turn it all into Ice not to mention that the expansion to which the Air tends upon the Account of its own spring is as we shew in another place many times greater then that to which Mersennus could bring it upon the bare Account of Heat 9. There remains yet one way whereby we hop'd though not to measure the Expansive force of freezing water yet to manifest it to be prodigiously great or in case we fail'd of this aim to produce at least some other Phaenomena relating to Cold that would not be inconsiderable And though our endeavours succeeded not yet because a happier opportunity may bring them to be one way or other succesful we shall annex That we caus'd to be made an Iron Ball of between two and three inches in Diameter which Ball was solid save that in the midst there was a small Cavity left to place a little water in together with a female screw as they call it reaching from the outward surface of that internal cavity and to this was applied a strong Iron screw so fitted to the internal cavity of the other screw as to fill it with as much exactness as could be obtained And this screw was made to go so hard that it requir'd to be screw'd in by the help of a Vice that it might not be forc'd out without breaking the Iron it self Our design in imploying this Instrument was that having well fill'd the internal cavity with water and forc'd in the screw as far as it could be made to go the Instrument thus charg'd with water might be expos'd to the highest degree of Cold we could produce For having thus ordered the matter we thought we might expect either that the water how much soever we heightned and lengthned the Cold would not freez at all being hindred from the Expansion belonging to Ice in comparison of water or if it did freez that one of these two things would happen either that the expansive force of that little water would by forcing such an Iron Instrument manifest its strength to be stupendious or by not breaking it present us with ice without Bubbles or at least not rarer and lighter then the water it was made of but for want of a sufficient Cold our designs succeeded not so as to satisfie us though we more then once attempted it For the great thickness of the Iron being consider'd we were not sure that the waters not freezing might not proceed rather from the thickness and compactness of the metal then from its resistence to the expansion of water And therefore we must suspend the inferences this Experiment may afford us till we have opportunity to make trial of it with a Cold not only very intense but durable enough the want of which last circumstance keeps us from daring to build any thing on our Experiment 10. And here we may take notice that it may be an inquiry more worthy a Philosopher then easie for him whence this prodigious force we have observ'd in water expanded by glaciation should proceed For if Cold be but as the Cartesians would have a privation of Heat though by the recess of that Ethereal substance which agitated the little Eel-like particles of the water and thereby made them compose a fluid body it may easily enough be conceiv'd that they should remain rigid in the Postures wherein the Ethereal substance quitted them and thereby compose an unfluid Body like Ice yet how these little Eels should by that recess acquire as strong an endeavour outwards as if they were so many little springs and expand themselves too with so stupendious a force is that which does not so readily appear And on the other side in the Epicurean way of explicating Cold though the Phaenomenon seems some what less difficult yet it is not at all easie to be salv'd For though granting the Ingress of swarms of Cold Corpuscles the Body of water may be suppos'd to be thereby much swell'd and expanded yet besides that these Corpuscles stealing insensibly into the Liquors they insinuate themselves into without any shew of boisterousness or violence 't is not so easie to conceive how they should display so strange a force against the sides of those strong vessels that they break when they may as freely permeat or enter them besides this I say we observe that in Oyl which requires a far greater degree of Cold to be congeal'd to a good degree of hardness the swarms of frigorifick Atoms that invade it are so far from making it take up more room then before that they reduce it into less as may appear by those former Experiments which manifested that
Cold does not expand either oyl or uncongealable Liquors but condense them 11. After what I have thus largely delivered concerning the expansive endeavour of freezing water I hope I may be allow'd to leave to others if they shall think it worth the labour the prosecution of the like Experiments upon Wine Milk Urine and other Liquors abounding with Aqueous parts concerning which we shall only in general remind those that may have forgotten it That by some of our Experiments it appears that such Aqueous Liquors are expanded by congelation and that their endeavour outwards is considerably forcible seems more then likely from what we formerly noted out of the Dutch Voyage to Nova Zembla where 't is related that by the extreme Cold both some of their other Barrels and some of those that were hooped with Iron were as they speak frozen in pieces that is according to our Conjecture burst together with the Hoops whether of Wood or Iron by the expansive force of the imprison'd Liquors brought to freez 12. To which I shall add that when I asked an Ingenious person whether in Russia where he liv'd a good while Beer and Wine did not when brought to congelation break the vessels they were frozen in He Answered That he had not observed wooden vessels to have been broken by them perhaps because of their yielding but glass and stone Bottles often Title XII Experiments touching a New way of estimating the Expansive force of Congelation and of highly compressing Air without Engines 1. THere is yet another way that I bethought my self of at once to measure the force wherewith freezing water expands it self and to reduce the Air to a greater degree of condensation then I have as yet found it brought to by any unquestionable way of compressing it But whereas by this method to determine exactly the Expansive force of the water it were requisite not only to know the quantity of the water and that of the Air exposed to the Cold but to make the Experiment in vessels conveniently shap'd to measure the Dilatation of the one and the compression of the other our Experiments being made in a place where we were not provided of such glasses we were not able to make our trials so instructive and satisfactory as else we might have done nevertheless we shall not scruple to subjoyn those of them that we find noted down among our Collections allowing our selves to hope that will not be unacceptable or appear impertinent not only upon the account of their novelty but for two other reasons 2. The first because though they do not accurately define the Expansive force of freezing water yet they manifest that it is wonderfully great better perhaps then any Experiment that has been hitherto practised not to say thought of as may appear by comparing what we have delivered in another Treatise of the great force requisite to compress Air considerably with the great compression of Air that has already been this way effected 3. The second because this new way affords us one of condensing the Air much farther then hitherto it has by any method I have heard of been unquestionably reduced I say unquestionably because though the diligent Mersennus and others seem to have conceived himself to have reduced it in the wind-Gun into a very narrow room yet besides that by our Expedient we have compressed it beyond what these Ingenious Men pretend to Besides this I say I have long much questioned whether the way of compressing Air in a wind-Gun which both they and we have imploy'd may safely be relied on for the oyl or some other analogous thing that is wont this way to be imploy'd and the overlooking of several circumstances that are more necessary to be taken into diligent consideration then wont to be so may easily enough occasion no small mistake in assigning so great a degree to the compression of the Air but our Exceptions against this way of measuring it may be more opportunely discours'd of in another place And therefore we will now proceed to take notice that of the two known ways of compressing Air the clearest and most satisfactory seems to be that which is performed in the wind Fountain as 't is commonly called where yet I have seldom if ever seen the Air that I remember by all the violence men could use to syringe in water crowded into so little as the third part of the capacity of the vessel And an ingenious Artificer that makes store of these Fountains being consulted by me about the further compressing of Air in them he deterr'd me from venturing to try it by affirming to me that both he and another skilful Person of my Acquaintance had like to have been spoiled by such attempts for endeavouring to urge the Air beyond a moderate degree of compression it not only burst some Fountains made of Glass but when the Attempt was made in a large but thick vessel made of strong and compact Flanders Earth the same with that of Jugs and stone Bottles the vessel was by the over-bent spring of the Air burst with a horrid noise and the pieces thrown off with that violence that if they had hit him or his Friend that assisted him in the Experiment they might have maimed him if not killed him out right so that the greatest unquestionable Compression of the Air seems to have been that recorded in the Fifth Chapter of our Defence against the learned Linus where nevertheless we could reduce the Air by the weight of a Cylinder of Mercury of about 100. inches which consequently might near countervale a Cylinder of six score foot of water but into a little less then a fourth part of its usual extent but how much further the Air may be compressed by our new purposed way it is now time to shew by the ensuing notes of which we have not omitted any that we could find both that some scruples which might else arise about the way we imployed may be prevented or satisfied and that the way we imployed in practising this method might by some variety of Examples be the better understood 4. We took a large glass-Egg with a Cylindrical stem about the bigness of my middle finger and pouring in water till it reach'd about a fingers breadth higher then the bottom of the stem we set it to freez in snow and salt for some hours with the stop of the stem which was drawn out into a very slender pipe almost at right angles with the stem open and there left it for some hours and the water was risen betwixt six and a half and seven inches This we did in order to another Experiment but then easily and nimbly sealing up the slender pipe above mentioned that the Air in the stem might not be heated we let it continue in the snow sometimes adding fresh for about 24. hours to observe to what degree the water by expanding it self would compress the imprison'd Air. The length of the Cylinder of
be some unheeded flaw or crack of the glass at which the Air had stollen out we drew near the vessel and attentively prying all about it to try if we could discover any ground of our suspition we found as far as the divided list and other circumstances could inform us that the Air supposing none of it to have got away was reduc'd by our Estimate into the 19. part of the space it possess'd before And this our curiosity prov'd not unseasonable for whilest we were narrowly surveying the glass to spy out some flaw in it we were quickly satisfied there had been none by a huge crack made upon the Eruption of the included Air whose spring being by so great a compression made too strong for the glass to resist it did with a great noise break the ball of the glass into many pieces throwing the unfrozen part of the water upon me and also throwing off the stem of the Egg which yet I had the good fortune to recover intire and which I yet keep by me as a rarity 10. Thus far we then proceeded in compressing the Air which being done in vessels Hermetically seal'd where no Air can get in or out seems to me a more unexceptionable way then those that have hitherto been thought of But further we could not then prosecute it for want both of convenient glasses and of ice or snow of which if we were provided and particularly of strong glasses we should little doubt of reducing the Air to a yet more considerable degree of compression 11. We may add on this occasion that we look'd upon the same way as somewhat less unpromising then others that have been hitherto us'd to try the compression of water for though hitherto neither the Experiments of Ingenious Men nor those made by our selves have fully satisfi'd us that water admits any more compression then it may suffer upon the account of the little parcels of Air that is wont to be dispersed among it yet the unsuccesfulness may perhaps for I propose it but as a mere conjecture be imputed to the porousness of the vessels wherein by the ways already practis'd the Experiment must be made whereas in this new way of ours not only the force wherewith the compress'd Air presses upon the water grows at length to be exceeding great and is appli'd not with a sudden Impetus as when a Pewter vessel is knock'd with a Hammer but by slow and regular degrees of increase but the water is kept in a vessel impervious to its subtilest parts so that it may indeed crack the glass but cannot get out at the pores as water compress'd is wont to do at those of metalline vessels The prosecution of this Experiment to bring it to any thing of Accurateness we omitted partly through forgetfulness and Avocations and sometimes for want of conveniency to try it But by the first of the lately mention'd Experiments about the condensation of Air it seems by the strong multitude of Bubbles which upon the breaking of the glass appear'd in the water that had been compress'd betwixt the Air and the 〈◊〉 that those two Bodies had very violently compress'd it and this we are the more apt to believe because that another time when we had seal'd up some Air and water in a glass-Egg and permitted the water to swell by the operation of the Cold but till it had reduc'd the Air included with it to about three quarters of the space it possest before even then I say to try whether the subjacent water were not also compress'd by the Air it urg'd we broke off the seal'd Apex of the glass and perceiv'd as we expected the water to ascend and that to the height of a quarter of an inch as we found by measure But such trials having not been as we just now acknowledg'd duly prosecuted we shall at present content our selves to have nam'd this way of attempting the compression of water without grounding any Inferences upon it Title XIII Experiments and Observations touching the sphere of Activity of Cold. 1. THe sphere of Activity of Cold or to speak plainer the space to whose extremities every way the action of a Cold body is able to reach is a thing very well worth the enquiring after but more difficult to find then at first one would imagine For to be able to assign the determinate limits within which and not beyond them a cold Body can operate several things are to be taken into consideration as first what the degree of Cold is that belongs to the assigned Body For it seems rational to conceive that if a cold Body as such have a diffusive vertue those that have greater degrees of Cold as Ice and Snow will be able to diffuse it to a greater distance as we see that a coal of Fire will cast a sensible heat much further then a piece of wood that is heated without being kindled Secondly the Medium through which the Diffusion is made may help to enlarge the Bounds or straiten the Limits of it as that medium is more or less dispos'd to receive or to transmit the Action of the cold Agent Thirdly Not only the Consistence and Texture of the Medium but its Motion or Rest may be considered in this case For in frosty and snowy weather men observe the winds that come from frozen lands to blow more cold then winds from the same Quarter would do in case there were no Ice nor Snow in their Passage Fourthly There may be made very differing Estimates of the Diffusion of Cold according to the Instrument that is imploy'd to receive and acquaint us with the Action of Cold. For a liquor or other Body may not appear cold to him that examines it with a Weather-glass whilest he shall feel it cold with his hand and as we elsewhere also note to that sensory it self as 't is variously dispos'd the same object will seem more or less cold so much may the Predisposition of the Organ impose upon the unskilful or unwary Fifthly The very bulk of a cold Body may very much inlarge or lessen its sphere of Activity as we may have occasion to shew ere long And besides there may be divers other things that may render it very difficult to ascertain any thing in this matter And therefore I shall reserve them for other opportunities and observe now in general that in such small parcels of Ice it self as in our Experiments we are wont to deal with we have found the sphere of Activity of Cold exceeding narrow not only in comparison of that of heat in fire but in comparison of the Atmosphere if I may so call it of many odorous Bodies as Musk Civet Spices Roses Wormwood Assa dulcis Assa foetida Castoreum Camphire and the like nay and even in comparison of the sphere of Activity of the more vigorous Loadstones insomuch that we have doubted whether the sense could discern a cold Body 〈◊〉 then by immediate Contact 2. And to
he inform'd me that it was their usual way to turn water and snow into ice by pouring a convenient Proportion of that liquor into a great quantity of snow and having also inquir'd 〈◊〉 ice had not the like operation he told 〈◊〉 that t was usual and he had seen it practis'd in 〈◊〉 to cement Ice to Buildings and other things and also to case over Bodies as it were with Ice by gradually throwing water upon them But I doubt whether that Effect be to be ascrib'd barely to the Contiguity of the Ice because I learn'd of him that this way of increasing ice is practis'd in very frosty weather when water thinly spread upon almost any other Body would be frozen by the vehement sharpness of the Air. 7. The Glaciations that nature unguided by Art is wont to make beginning at those parts of Bodies at which they are expos'd to the Air it usually happens that they freez from the upper towards the lower parts But how far in Earth and Water the most considerable Bodies that are subject to be frozen the frost will pierce downwards though for some hints it would afford worth the knowing is not easie to be defin'd because the deepness of the frost may be much varied by the degree of Coldness in the Air by which the Glaciation seems to be produc'd as also by the greater or 〈◊〉 Duration of the frost by the looser or closer texture of the Earth by the nature of the Juices wherewith the Earth is imbu'd and by the constitution of the subjacent and more internal parts of the Earth some of which send up either actually warm or potentially hot and resolving steams such as those that make corrosive liquors in the bowels of the Earth so that the frost will not seiz upon or at least cannot continue over Mines and I have seen good large scopes of land where vast quantities of good Lime-stone lay near the surface of the Earth on which I have been assur'd by the Inhabitants that the snow will not lye There are divers other things that may vary the depth to which the frost can penetrate into the ground I say into the ground because in most cases it will pierce deeper into the water But yet that we may not leave this part of the History of Cold altogether uncontributed to we will add some of our Notes whereby it will appear that in our Climate the 〈◊〉 〈◊〉 〈◊〉 less into the ground then many are pleas'd to think 8. The notes I find about this matter are these that follow which I 〈◊〉 unaltered because 't were tedious and not worth while to add the way we imploy'd and the cautions we us'd in making the observations but we shall rather intimate that the following trials were made in a Village about two miles from a great City I. Jan. 22. After four nights of frost that was taken notice of for very hard we went into an Orchard where the ground was level and not covered with grass and found by digging that the frost had scarce pierc'd into the ground three inches and a half And in a Garden nearer the house we found not the Earth to be frozen more then two inches beneath its surface II. Nine or ten nights successive frost froze the grasless ground in the Garden about six inches and a half or better in depth and the grasless ground in the Orchard where a wall 〈◊〉 it from the south Sun to the 〈◊〉 of about eight inches and a half or better February the 9. we digg'd in an Orchard near a wall that respects the North and found the frost to have 〈◊〉 the ground 〈◊〉 a foot and two inches at least above a foot 〈◊〉 〈◊〉 the eight day since it was 〈◊〉 〈◊〉 inches and a half A slender pipe of glass about 18. inches long and seal'd at one end was thrust over night into a hole purposely made with a Spit straight down into the ground the 〈◊〉 of the water being in the same level with that of the Earth the next morning the Tube being taken out the water appear'd frozen in the whole Capacity of the Cylinder but a little more then three inches But from this stick of ice there reach'd downwards a part of a Cylinder of ice of about six inches in length the rest of the water remain'd 〈◊〉 though it were an exceeding sharp night preceded by a Constitution of the Air that had been very lasting and very bitter The Earth in the Garden where this Trial was made we guess'd to be frozen eight or ten inches deep as it was in another place about the same house But is this Tube had not been in the ground the ambient Air would have frozen it quite through 9. Another Note much of the same import we find in another place of our Collections Finding that by reason of the mildness of our Climate I was scarce to hope for any much deeper Congelation of the Earth or Water I appli'd my self to inquire of an Ingenious Man that had been at Musco whether he had observed any thing there to my present purpose as also to find in Captain James's Voyage whether that inquisitive Navigator had taken notice of any thing that might inform me how far the Cold was able to freeze the Earth or Water in the Island of Charleton where that Quality may probably be supposed to have had as large a sphere of Activity as in almost any part of the habitable world And by my Inquiries I 〈◊〉 that even in frozen Regions themselves a congealing degree of Cold pierces nothing near so deep into the Earth and Sea as one would imagine For the Traveller I spoke with told me that in a Garden in Musco where he took notice of the thing I inquir'd about he found not the ground to be frozen much above two foot deep And in Captain James's Journal the most that I find and that too where he gives an Account of the prodigiously tall ice they had in January concerning the piercing of the frost into the ground is this that The ground at tenfoot deep was frozen Whence by the way we may gather how much sharper Cold may be presum'd to have reigned in that Island then even in Russia And as for the freezing of the water He does in another place occasionally give us this memorable Account of it where He relates the manner of the breaking up the Ice in the frozen Sea that surrounds the Island we have been speaking of It is first to be noted says he that it doth not freez naturally above six foot the rest is by accident such is that Ice that you may see here six fathome thick This we had manifest proof of by our digging the Ice out of the Ship and by digging to our Anchors before the Ice broke up The rest of that account not concerning our present purpose I forbear to annex only taking notice that notwithstanding our lately mention'd Experiment of freezing water in
a glass Tube thrust into the Ground yet it seems that at least where Captain James winter'd the water was not much above half so thick frozen as the Earth But we have already noted the indisposition of salt-water to congelation and whether fresh water would not have been deeper frozen may be justly doubted Title XIV Experiments touching the differing Mediums through which Cold may be diffus'd 1. IN examining whether Cold might be diffus'd through all Mediums indefinitely notwithstanding their Compactness or the Closeness of their Texture we must have a Care not to make our Trials with Mediums of too great thickness least we mistakingly impute that to the Nature of the Medium which is indeed caus'd by the distance which the Medium puts betwixt the Agent and the Patient For the mixtures of Ice and Snow wherewith we made our Experiments will operate but at a very small distance though the Medium resist no more then the common Air as may appear by some of the Experiments recorded in this Treatise This premis'd we may proceed to relate that having plac'd a copious mixture of ice and salt in Pipkins glaz'd within and in white Basons glaz'd both within and without we observ'd that the outside of both those sorts of vessels was crusted over with ice though however the bak'd Earth had not been compact nor the vitrifi'd surfaces of a very close Texture the very thickness of the vessels was so great that it seem'd it would scarce have been able to freez at a greater distance 2. By the Experiments formerly mention'd of freezing water in Pewter bottles it appears that Cold is able to operate through such mettalline vessels 3. And this may be somewhat confirm'd by one of the prettiest Experiments that is to be perform'd by the help of Cold namely the making Icy Cups to drink in The way we us'd was this We caus'd to be made a Cup of Lattin by which I mean Iron reduc'd into thin plates and tinn'd over on both sides of the shape and bigness I intended to have the Cup of then I caus'd to be made of the same matter another Cup of the same shape with the former but every way less so that it would go into the greater and leave a competent interval for water betwixt its convex surface and the concave of the other This innermost Cup was furnished with a rim or lip by which it lean'd upon the greater and by whose help its sides and bottom were easily plac'd at a just and even distance from the sides and bottom of the other but the Distance between the two bottoms is made greater then that between the sides that the icy Cup might stand the firmer and last the longer The interval between the two parts of this Mould being fill'd with water and the Cavity of the internal Cup being fill'd with a mixture of ice and salt partly to freez the contiguous water and thereby cooperate to the quicker making of the Cup and partly by its weight to keep the water from buoying up so light a Cup the external part was surrounded with ice and salt whose Cold so powerfully penetrated to the internal metalline Mould that the water was quickly frozen and the Parts of the Mould being disjoyn'd appeared turn'd into an icy Cup of the bigness and figure design'd And these Cups being easily to be made and of various shapes and that in the midst of Summer if snow or ice be at hand are very pleasant triffles especially in hot weather when they impart a very refreshing coolness to the drink poured into them and though they last not long especially if they be imploy'd to drink Wine and such like spirituous Drinks in yet whilest some are melting others may be provided and so the loss may be easily repair'd all the difficulty we met with was to disjoyn the parts of the Mould which are wont to stick very fast to the ice they include And we tri'd to obviate this sometimes by annointing the inside of the Mould with some unctuous and not offensive matter to hinder the Adhesion of the ice and sometimes by applying some convenient heat both to the convex part of the external and the concave part of the internal piece of the Mould which last mention'd way is quick and sure but lessens the durableness of the Cup. We were lately inform'd that this way of making Cups of Ice is set down 〈◊〉 〈◊〉 Argenis and 't is like enough that 〈◊〉 Man may have learn'd it amongst some of the Virtuosi of Italy he convers'd with But if we that learn'd it from none of them had not been taught it by Experience we should scarce have ventur'd to try it upon the Credit of a Romance that sort of Composures being wont to be fabulous enough to pass but for Poems in Prose 4. The learned and industrious Mathematician Erasmus Bartholinus mentions in his newly publish'd Discourse de Figura 〈◊〉 an Experiment by which he tells us that some Masters of Natures secrets do easily even in the midst of heat reduce water into Air. For they put a little snow or ice into a Funnel and thereby so refrigerate and condense the ambient Air that there will dew trickle down the sides of the Funnel By which means it has been said that some Ingenious Men have hop'd to make an artificial Fountain in the midst of Summer But I here mention this Experiment rather because 't is not unlikely to please those to whom 't is new and because having purposely tri'd it in large and thick funnels of glass it may be pertinently enough deliver'd in this place where we are treating of the Transmission or Propagation of Cold through close and thick Mediums then because we expect to make of it that use especially that Oeconomical use that has been lately intimated For first 't will be very hard to prove that 't is the very Air it self and not rather the vapours swimming in it that are by this means transmuted into water And secondly 't is true indeed that a mixture of snow and salt will condense vapours on the outside of a Funnel but either they that hop'd to make this use of the Experiment have little Experience of it and write conjecturally or else they have made it with a success very differing from ours For though we imploy'd a large Funnel and suspended it by a string artificially enough ti'd about it in the free Air And though the mixture of ice and salt we put in were sufficiently infrigidating as will appear by and by and far more so then ice or snow alone would have been yet that mixture being not able to condense the vaporous Parts of the Air into dew much if at all longer then the mutual Dissolution of the salt and snow lasted the liquor that was this way obtain'd and dropp'd down at the bottom of the Funnel whose internal Perforation ought to be carefully stopp'd least any of the resolved snow and salt should fall through
common salt but the Experiment succeeded not well though once we brought the ice to stick to the wood manifestly but not strongly 8. To this we shall add the following Experiment which when we watchfully made it succeeded well and I find it among my notes set down in these terms Solid fragments of ice having pretty store of salt thrown on them upon the first falling of the salt among the ice there was produced a little 〈◊〉 noise and for a good while after there manifestly ascended out of several parts of the mixture conveniently held betwixt a candle and the eye a steam or smoak like that of warm meat though the night were rainy and warm and though the morning had not been frosty The mention here made of the crackling noise made by the ice upon the addition of salt which seemed to proceed from the crackling of the brittle ice produc'd by the operation of the salt upon it brings into my mind an Experiment I had formerly made whereof a greater noise of the same kind is a Phaenomenon though the Experiment were chiefly made for the Discovery of the texture of Ice The event of the trial I find thus set down among my notes 9. We took some cakes of ice each of the thickness between an 〈◊〉 and a ¼ part of an inch but not so very compact ice as to be free from store of bubbles some good Aqua fortis dropp'd upon this did quickly penetrate it with a noise that seem'd to be the cracking of the ice underneath which the sowre liquor was very plainly to be tasted Oyl of Vitriol did the same but much more powerfully and without seeming to crack the ice which it past through so that though but three or four drops were let fall upon the plate it immediately shew'd it self in drops exceedingly corrosive on the other side of the ice And the like success we had with a trial made with the same liquor upon three such plates of ice frozen one upon the top of another 10. Having proceeded as far as we were able towards the bringing the strength of ice to some kind of Estimate by such Experiments as we had opportunity to make here we thought it not amiss to seek what information we could get about this matter among the Descriptions that are given us of Cold Regions But I have not yet found any thing to have been taken notice of to this purpose worth transcribing except a passage in the Arch-Bishop of upsal wherein though the estimate of the force of Ice be as we shall by and by show 〈◊〉 after a gross manner yet since this it self is more then I have met with elsewhere I think it worth subjoyning as our Author delivers it in these terms Glacies says he primae mediae hyemis adeò fortis tenax est ut spissitudine seu densitate duorum digitorum sufferat hominem Ambulantem trium vero digitorum equestrem Armatum unius palmae dimidiae turmas vel exercitus militares trium vel quatuor palmarum integram Legionem seu myriadem populorum quemadmodum inferiùs de bellis Hyemalibus memorandum erit But though this be sufficient to afford us an illustrious Testimony of the wonderful strong cohesion of the parts of ice yet we mention'd it but as a popular way of estimate which may better embolden Travellers then satisfie Philosophers in regard that the Author determines only the thickness of the ice and not the distance of that part of it that supports the weight from the shore or brink on which as on a Hypomochlion the remotest part of the ice does lean or rest And if we consider the ice as a Lever and the Brink or Brinks on which it is supported as a single or double sulcrum the distance of the weight may be of very great moment in reference to its pressure or gravitation on the ice which may much more easily support the weight of divers men plac'd very near the prop then that of one man plac'd at a great distance from it as will be easily granted by those that are not strangers to the Mechanicks especially to the nature and properties of the several kinds of Levers But not now to debate whether in certain cases the ice we speak of may not receive some support from the subjacent water nor whether some other circumstances may not sometimes be able to alter the case a little our very considering the ice as a single or double Lever though it may hinder us from measuring the determinate strength of ice upon Olaus's Observation yet it will set forth the strength of it so much the more since by his indefinite expressions he seems sufficiently to intimate that when the ice has attain'd such a thickness its resistance is equivalent to such a weight without examining on what part of the ice it chances to be placed 11. Thus far our Experiments concerning ice with the Appendix subjoyned out of Olaus to the same purpose We will now proceed to some of the observations we have met with in Seamens Journals and elsewhere I say to some because to enumerate them all would spend more time and labour then I can afford and therefore I shall restrain my self to the mention of some few of the chiefest I. And in the first place for confirmation of what I deliver'd at the beginning of this Section from the report of a Traveller into Russia touching the hardness of ice in those gelid Climates in comparison of our ice which I have found it easie to scrape with glass or to cut with a knife I shall subjoyn this passage of Captain G. Weymouth in his Voyage for the Discovery of the Northwest passage As we were says he breaking off some of this Ice which was very painful for us to do for it was almost as hard as a rock c. II. Next to shew that it was not a superfluous wariness that made me in a former Section doubt that even the ice made of Sea-water might be altogether or almost insipid I will subjoyn that I have since met with some Relations that seem to justifie what is there deliver'd And in one of our Englishmens Voyages into the Northern Seas I find more then one instance to my present purpose though I shall here set down but one which is so full and express that it needs no companions Our Navigator speaking thus About nine of the Clock in the forenoon we came by a great Island of Ice and by this Island we found some pieces of Ice broken off from the said Island and being in great want of fresh water we hoysed out our Boats of both Ships and loaded them twice with Ice which made us very good fresh water But all this notwithstanding I yet retain some scruple till those that have better opportunity to make a more satisfactory Experiment shall ease me of it For though by these Narratives it seems more then probable that the ice
in the midst of the Sea consists but of the fresh Particles of water that plentifully concur to compose the Sea water yet besides that in case the fresh water were taken as some of that I have found mentioned in Voyages has confessedly been from the top of the ice it might possibly be no more then melted snow which as we elsewhere take notice does in those extremely cold Regions easily freez upon the ice it falls on and oftentimes much increases the height of it Besides this I say the Argument from the insipidness of the resolved ice will conclude but upon supposition that as that ice was found in the Sea so it was also made of the Sea water which though it may have been yet I somewhat doubt whether it were or no since I find some Navigators of the most conversant in the cold Climates to inform us That most of those vast Quantities of ice that are to be met with about Nova Zembla and the strait of Weigats and that choke up some other passages whereby men have attempted to pass into the south Sea are compos'd of the accumulation of numerous pieces of ice cemented together by cold water that are brought down from the great River Oby and others so that it may very well be suppos'd that these mountainous pieces of ice may be some of these which upon the shattering of ice in Bays and straits partly by the heat of the Sun and partly by the Tides may be afterwards by the winds and currents driven all up and down the Seas to parts very distant from the shore and some of these it may be that our Countreymen met with and obtain'd their fresh water from Which I the rather incline to think because that as we shall have occasion to observe in another Section the main Sea it self is seldom or never frozen But my scope in all this is but to propose a scruple not an opinion III. The next and principal thing concerning ice is the bigness of it which I find by the Relations partly of some Acquaintances of my own and partly of some Navigators into the North to be sometimes not only prodigious but now and then scarce credible And therefore as I shall mention but few instances that I have selected out of the best Journals and other writings I have met with so I shall add a few more Testimonies to keep them by their mutual support from being entertain'd with a Disbelief which their strangeness would else tempt men to Of the vastness of single mountains of ice the most stupendious Example that for ought I know is to be met with in any language but ours is that which I formerly took notice of out of the Dutch Voyage to Nova Zembla which was ninty six foot high that is above twenty foot higher than on a certain occasion I found the Leads of Westminster Abbey to be But 't is probable that our Captain James met with as great if not greater For though in some places he mentions divers hills of Ice that were aground in 40. fathom water and consequently were as deep under water as that newly taken notice of out of the Hollanders And though he elsewhere mentions other pieces of no less depth and twice as high as his top-Mast head and this in June yet elsewhere and long after relating his return home he has this passage We have sail'd through much mountainous Ice far higher then our Top-Mast head But this day we sail'd by the highest that I ever yet saw which was incredible indeed to be related But the stupendiousest piece for heighth and depth of single Ice that perhaps has been ever observ'd and measur'd by men is that which our Famous English Seaman Mr. W. Baffin whose name is to be met with in many modern Maps and Globes mentions himself to have met with upon the coast of Greenland whose whole Relation I shall therefore subjoyn not only because of the stupendiousness of this piece of ice but because he takes notice of an observation which I knew not to have been made by any and comes somewhat near the estimate we formerly made of the proportion betwixt the extant and immers'd parts of floating ice only the following Estimate makes the extant part somewhat greater then we did which may easily proceed from other mens having as Mr. Baffin here does grounded their computation upon what occurr'd to them at Sea or in salt water where the ice must sink less then in fresh water such as my Estimate suppos'd Our Navigators words then are these The 17. of May we sail'd by many great Islands of Ice some of which were above 200. foot high above water as I prov'd by one shortly after which I fonnd to be 240. foot high and if the report of some men be true which affirms that there is but one seventh part of Ice above water then the height of that piece of Ice which I observed was one hundred and forty fathoms or one thousand six hundred and eighty foot from the top to the bottom This proportion I know doth hold in much Ice but whether it do so in all I know not Thus far of the height and depth of single pieces of ice as for the other Dimensions the length and breadth I remember not that I have read of any that had the Curiosity to measure the extent of any of them excepting Captain James whose Ship being once arrested between some flat and extraordinary large pieces of ice he and his men went out to walk upon them and he took the pains to measure some of the pieces which he says he found to be a 1000. of his paces long And probably among so many mountains and Islands of ice there would have been found some intire pieces of a greater extent then even these if men had had the curiosity to measure them Hitherto we have treated of the bigness of single pieces of ice we will now proceed to say something of the dimensions of the aggregates of many of them among which having selected four or five as the principal I remember my self to have yet met with I presume it will be sufficient to subjoyn them only About ten of the clock we met with a mighty bank of ice being by supposition seven or eight leagues or twenty four miles long says that experienced English Pilot James Hall in his Voyage of Denmark for the discovery of Greenland Another of our English Navigators mentions that even in June all the Sea wherein he was indeavouring to sail as far as he could see from the top of a high hill was covered with ice saving that within a quarter of a mile of the shore it was clear round about once in a Tide By which last clause it seems that this vast extent of ice was either one intire floating Island or at least a vast bank or rand as some Seamen term it of ice But the strangest account of banks of ice that
I have yet met with in any sober Author is that which is mention'd by the learned French Hydrographer Fournier who relates that in the year 1635. the French fleet sailing to Canada met with several pieces of ice as high as steeples and particularly one whether piece or bank of ice for the French word Glace may signifie either which they were troubled to coast along for above forty leagues If this be the same story as one may suspect it to be by the circumstances of the place and fleet there is a great mistake in another place where our Author speaks of the vastness of the ice but if it be another story as some differing circumstances argue the French it seems met with ice far more stupendious then even that already mentioned For says our Author in the Sea which washes Canada there is often seen even in the moneth of August to pass by Ices much bigger then Ships In the year 1635. the French Fleet sailing there coasted along for three days and three nights one that was above 80. leagues long flat in some places like vast Champions and high in others like frightful hills The latter part of which passage may confirm what we formerly deliver'd in another Section concerning the unequal compagination of 〈◊〉 Islands To what has been said touching the extent and other dimensions of floating or at least loose pieces of ice it will be fit to add something of the extent of ice coherent to one or both of those shores that bound the water whose upper part is congeal'd And in the first place we shall out of many instances to our present purpose that might be borrowed from the writings of Olaus Magnus select this one memorable one that shall serve for all Neque minori bellandi impetu says he Sueci ac Gothi super aperta glacie quam in ipsa solidissima terra confligunt imo ut prius dictum est ubi antea aestivo tempore acerrima commissa sunt bella Navalia eisdem in locis 〈◊〉 concreta aciebus militari modo instructis Bombardis ordinatis habentur horrendi conflictus Adeo solida glacies est in equestribus turmis sufferendis amplitèr vel strictè collocatis I pretermit then what he elsewhere relates of the Voyages and Wars made in Winter by the Northern Nations They that have liv'd in those Countries relate as things most known and samiliar what has been confirmed to me by more then one unsuspected eye witness the long Journeys that are commonly taken upon the Icy Bridges or rather plains by travellers with all their Carriages to very distant places And that which may bring credit to these strange relations by shewing that no less unlikely ones are sometimes true is what all Europe knows that within these three years the whole Swedish Army led on by their King march'd over the Sea to the Island of Zeeland where Copenhagen the Capital City of Denmark stands But it may seem much more strange which I will therefore add that as in the North Countries frequently so sometimes even in the warmer Regions of the East the Sea it self has by the Cold been congeal'd to a prodigious breadth Insolitum est saith Bartholinus quod refert Constantinus Manasses in Annalibus accidisse Theophilo imperante ut hyems saeva mare cogeret in glaciem ad profunditatem sanè immensam humidúinque illud Elementum Lapidis ad duritiem fluxione prorsus ademptâ redigeret And Michael Glycas relates That in the year 775. the Winter was so sharp in the East that along the Coast the Sea he means the Mediterranean was frozen for 50. leagues and the Ice was compacted as into a rock 30. Cubits deep so strange a Quantity of snow likewise falling that it was rais'd to the height of 30. Cubits above the Ice which likewise agrees very well with what we formerly noted touching the possible increase of the height of some pieces of ice by the falling of the snow upon them IV. It remains now that we subjoyn a few promiscuous observations concerning ice that are not so readily reducible to the three foregoing heads And we shall begin with what was taken notice of by the Dutch in their Nova Zembla Voyage where relating how they fastned their Ships to a great piece of ice to shelter themselves from the stormy winds There add they we went upon the ice and wondred much thereat it was such manner of Ice for on the top it was full of earth and there was found about 〈◊〉 eggs and it was not like other ice for it was of a perfect Azure colour like to the skies whereby there grew great contention of words amongst our men some saying that it was ice others that it was frozen land for it lay unreasonable high above the water it was at least eighteen fathom under the water close to the ground and ten fathom above the water The like blew colour in rocky pieces of ice I remember I have somewhere found to have been taken notice of by a modern Navigator or whether the words of Virgil concerning the frigid Zone Caerulea glacie concretae atque imbribus atris belong to this subject I leave others to consider nor shall I stay to examine whether this blewness that has been observ'd in ice be always an inherent or permanent colour or else sometimes one of those that are styl'd Emphatical 'T is very considerable if it be true what is related by Olaus Magnus concerning the degenerating if I may so speak of ice from its wonted hardness in the Spring of the year For in the same Chapter where he gives us the lately transcribed account of the strength of Ice in those Northern Countries after having interpos'd some other passages he subjoyns these words Liquescente tamen glacie ad principium Aprilis nullus ejus spissitudini minus fortitudini nisi in aurora ambulando confidit quia solis diurno aspectu tam fragilis redditur ut quae-equestres armatos paulo ante portaverat vix hominem nunc sufferre possit inermen This puts me in mind to add that oftentimes in the writers of Journies and Voyages we meet with mention of great noises made by the breaking of ice and in this very Chapter our Archbishop taking notice of the clefts that sometimes happen in Champions of ice adds That when the ice chances thus to open especially if it be in the night the noise of it maybe heard a far off like the loud and horrid noise of thunder and of earthquakes And on this occasion may be subjoyned a couple of passages extant in different places of the formerly mention'd Hall's Voyages The first is thus delivered When we met with a huge and high Island of ice we steering hard to board the same and being shota little too Northwards of it there fell from the top thereof some quantity of ice which in the fall did make such a noise as though it had been the report
of five Canons But the next passage is more directly pertinent to our present subject and is couch'd in these words About twelve of the clock this night it being still calm we found our selves suddenly compassed round about with great Islands of ice which made such a hideous noise as was most wonderful so that by no means we could double the same to the westward wherefore c. Of these kind of icy thunders as some travellers call them there are divers instances to be met with mention'd in the several Voyages of the Hollanders particularly in those to Nova Zembla But many of those noises seem to be made by the dashing of the great pieces of ice against one another But if it happen when the ice as sometimes it is said to do seems to cleave as it were of its own accord to us that live in a temperate Climate it may be a matter of some dispute whence these loud ruptures of ice may proceed For Olaus Magnus in the Chapter above cited does not improbably ascribe them to the warm exhalations that in some places ascend out of the ground And I remember in favour of this opinion that I once caused divers pieces of thick ice to be brought out of a cool place into a somewhat warm room and listening observ'd a noise to come from them as if it had been produced by store of little cracks made in them but somewhat or other prevented me from repeating the Experiment and satisfying my self about the Conjecture But having lately inquired of an intelligent Polander that has travelled much upon these icy plains he agreed with our Author and others as to the frightful noise that are produc'd by these cracks of ice but affirm'd upon his own observation for that I particularly inquired after that these great clefts were often made not by thawing heat but by excessive cold and that he had taken notice of them in extremely sharp weather Indeed we sometimes observe that in very bitter frosts the frozen ground will cleave as we elsewhere have occasion to take notice But whether that be not a different case from this or whether the Polonian Gentleman were not mistaken or whether both these mention'd accounts of the cleaving of ice may on different conjunctures of circumstances take place we leave to farther inquiry There is a tradition concerning ice about the famous Volcan-Hecla in Island which though verily believ'd among the superstitious vulgar of those parts is spoken of so slightly by Blefkenius who being upon that coast had the curiosity to sail purposely thither that I think it not worth while to take any farther notice of it But 't were too tedious to set down in this Section which the strangeness and variety of the Theme has made so prolix already the other things that may be mentioned without impertinency concerning ice and therefore we shall here desist from so laborious a task as also omit the handling of snow and hail For though they are reducible to ice yet I shall at least suspend the treating of them partly because Bartholinus and Meteorologists have sav'd much of my labour and partly for the reason newly intimated so that we shall conclude this Section as soon as we have taken notice that there is yet somewhat relating to ice which being in itself considerable and whereof hitherto no experimental account appears to have been given what we our selves have tried about it may challenge to be treated of apart Title XVI Experiments and Observations touching the duration of Ice and Snow and the destroying of them by the Air and several Liquors 1. IT may be an Experiment as well instructive as new to determine what liquor dissolves ice sooner then others and in what proportion of quickness the solutions in the several liquors are made For Men have hitherto contented themselves to suspect in general that there are other liquors potentially hot wherein ice will sooner dissolve then it will in water But this opinion either being grounded upon no Experience at all or taken up upon the sight of what happens to pieces of ice which no care was taken 〈◊〉 reduce to the same bulk and figure no more then to measure attentively how long one outlasted the other we thought fit to try if we could not bring this matter to Experiment and make a determination in it though not exactly true yet less remote from exactness then had been yet for ought I know so much as attempted 2. In order to this we procured some bullet moulds and having first carefully stopped the little Crevice that is wont to remain betwixt the two halfs of the mould with a good close Cement we afterwards filled them with water and carefully closed up the orifice of the hole at which the water was poured in and then setting the mould to freez in ice and salt we found it difficult enough to keep the water more or less of it from running away through some unperceiv'd passage before the cold could have time by congealing it to arrest it But after a while when we had thus made a bullet of ice we found it a new and greater difficulty to get it whole out of the moulds without warming them for by that way we could indeed loosen the ice but then we could not avoid thawing it too and that most times not uniformly wherefore we tried by greasing the inside of the moulds to keep the ice from sticking so close to them notwithstanding the distention the water suffered by its being frozen but that we might pick out the bullet entire and this succeeding well enough we hoped by this way to obtain our end which was to have a competent number of pieces of ice of equal bulk and of the same figure to be put at once to thaw in several liquors but we could by no means procure moulds which had any number of distinct cells of the same bigness those long pairs of moulds that were to be met with in shops having their distinct cells generally made on purpose of very different bignesses which rendred them altogether useless for our design Wherefore we were fain for want of an exacter way to take a glass pipe of the most even and Cylindrical that we had and of a bore capable to admit a big mans little finger this glass being stopt at one end and kept open at the other was filled to the height of about half a foot or more of fair water and ice and salt being heaped up about it that the cold might reach as far as the 〈◊〉 did it was quickly frozen In the mean while I had caused several wide mouth'd glasses to be brought into my Chamber wherein by reason of some indisposition that hindred me from going abroad I kept some fire and having poured several liquors into these glasses which had been placed all on a row we suffered them to rest there a while that the ambient Air might have time to reduce them as far
with him supplied him so well with Air that he was not incommodated in point of Respiration and though he felt no other inconveniencies that might disswade his tarrying longer yet the cold was so great and troublesome that he was not able to endure it above two or three hours but was constrain'd to remount to a milder as well as a higher Region I wish'd several times he had had with him a seal'd Weather-glass for ordinary Thermometers would on that occasion have been unserviceable to prevent some little doubt that might be made whether the intense Cold he felt might not be only and chiefly in reference to his Body which might be so alter'd and dispos'd by this new Briny Ambient as to make such a disturbance in the course or texture of his Blood as that which makes Aguish persons so cold at the beginning of the fit though the temperature of the Ambient Body continue the same But this is not the only person that found the Sea Exceeding cold for I remember Beguinus relates from the mouth of a Marseillian Knight that was overseer of the Coral-fishing in the Kingdom of Tunis that having upon that coast let down a young man to feel whether Coral were hard or soft as it grew in the water when this man was come about eight fathom near the Bottom of the Sea he felt it exceeding cold To which we shall add the testimony of a sober Traveller Josephus Acosta who tells us That it is a thing remarkable that in the depth of the Ocean the water cannot be made hot by the violence of the Sun as in Rivers Finally he subjoyns even as Salt-Petre though it be of the nature of Salt hath the property to cool water even so we see by experience that in some parts and havens the salt water doth refresh the which we have observed in that of Callao where they put the water or wine which they drink into the Sea in Flaggons to be refreshed whereby we may undoubtedly find that the Ocean hath this property to temper and moderate the excessive heat For this cause we feel greater heat at Land then at Sea caeteris paribus and commonly Countries lying near the Sea are cooler then those that are farther off By all these testimonies it seems to appear that both in very cold Regions and very hot the deep parts of the Sea seem to be very Cold the Sun beams being not able to penetrate the Sea to any great depth for I remember that having enquired of the Diver I lately mentioned whether he could discern the light of the Sun at any great distance from the surface of the water he answered me that he could not but as he went down deeper and deeper so he found it darker and darker and that to a degree that would scarce have been expected in so Diaphanous a Body as water is 17. But this submarine cold if I may so call it though it be great and considerable is not so intense as to intitle water to be the primum frigidum since as cold as our Divers found it at the bottom of the Sea they did not find it cold enough to freez the water there as the Air often does at the Top. 18. The next Opinion we are to consider is that of the Stoicks of old and adopted by the generality of Modern Philosophers that are not Peripateticks who assert the Air to be the primum frigidum But being ere long more particularly to treat of the Temperature of the Air we will reserve till then to examine whether it be cold of its own nature or not but in the mean time we shall here take leave to question whether it ought to be esteem'd the primum frigidum For not to mention that Aristotle and the Schools with many other learned men think the Air so far from being the coldest of the Elements that they reckon it among the hot ones because I confels their opinion is not mine not to represent the heat of the Air in the Torrid Zone nor that by the generality of Philosophers the upper Region of the Air which is believed to make incomparably the greatest part of it is always hot and the lower Region is so too in comparison of the middle though the coldness even of this is not perhaps unquestionable not to urge any of these things I say I shall in this place mention only two observations 19. The one is that which I lately recited touching the great coldness of the water in the deeper parts of the Sea for'tis not easie to show how this great cold proceeds from that of the Air whose operation seems not as may be judg'd by that little way that frosts pierce into the moist Earth to reach very far beneath the surface of the water insomuch that Captain James who had very good opportunity to try allows not in case the Ice be not made by accumulation that the Frost pierces above two yards perpendicularly downwards from the surface of the water even in the coldest habitable Regions And this will seem the more rational if we consider that in case the coldness of the Sea proceeded constantly from the Air as such the cold would be greater near the surface where 't is contiguous to the Air then in the parts remoter from it and yet the contrary may appear by the passages lately recited 20. But if it be objected that this at best can prove no more then that the Air is not the primum frigidum notwithstanding which it may be the summum frigidum For answer I must proceed to my second Argument which will perhaps evince that it is not that neither for by the same way of arguing by which those I am now dealing with endeavour to prove the Air to be the coldest Body in the World I shall endeavour to prove that it is not so For their grand and as far as I remember their only considerable Argument is drawn from Experience which shows that water begins to freez at the Top where 't is exposed to the Air but to this vulgar Experiment I oppose that of mine which I have often mentioned already to other purposes that by an application of salt and snow I can make water that would else freez at the Top begin to freez at the Bottom or at any side I please and that much sooner then the common Air even in a sharp frosty night would be able to congeal it and when in exceeding cold weather the Ambient Nocturnal Air had reduc'd a parcel of Air purposely included in a convenient glass to as great a degree of condensation as it could I have more then once by the External application of other things been able to condense it much farther which argues that 't is not the Air as such but some adventitious frigorifick Corpuscles taking that term as I do in this Treatise in a large sense that may sometimes be mingled with it which produce the notablest degrees of
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
disapproved because it was likely and indeed we found it so by experience that the external air would first freez the uppermost part of the water contain'd in the stem and thereby hinder its ascent and perhaps occasion the bursting of the lower part of the said stem 8. Wherefore though for want of a sufficient Quantity of some liquor that would neither freez like water and aqueous Bodies nor congeal like common oyl and the like unctuous Juices we found it for a while somewhat difficult to practise the Experiment yet bethinking our selves of the indisposition that Brine has to Congelation we made so strong a Brine with common salt that with it and as I remember with oyl of Turpentine also of which we chanc'd to have some quantity by us we made divers Trials of which I had two among our Collections which we shall here subjoyn whereof the one informs us that an Egg being inverted into salt water the Cold of a frosty night made the air shrink in the Pipe near five inches and the other which is the accuratest I meet with among my Collections gives me this account That January the 29. the Air extended into 2057. spaces was by the cold of the sharp and frosty night contracted into 1965. spaces so that in extraordinarily cold weather the most we could make the Air lose of its former dimensions by the additional Cold of the Atmosphere was a 22. part and a little more then a third And this was the greatest condensation of the Air that we remember our selves to have observ'd though we were so careful as after we had placed marks where the incongealable liquor reach'd in the pipe that when the internal air was expos'd abroad to the cold we caused servants to watch and from time to time to take notice by placing marks of the various ascents of the liquor especially early in the morning least we should omit taking notice of the greatest contraction of the air which omission by reason that the Coldness of the ambient air does oftentimes begin to be remitted before we can feel it to be so is not easily avoided without watchfulness 9. But having thus observ'd the Condensation of included air by the natural and unassisted Cold of the external air we thought fit to prosecute the trial somewhat further and in regard we conceiv'd the Cold of a mixture of snow and salt to be far more intense then that of the mere ambient air alone we endeavoured to measure as near as we could how much the one exceeded the other And though we found that by prosecuting the lately mention'd Trial in the glass-Egg by the application of ice and salt to the Elliptical part of the vessel the liquor rise by our Estimate near four inches more then those five which it had risen already upon the account of the Refrigeration of the included air by the bare cold of the external Yet by prosecuting the other Experiment made the 29. of January at the same time when we were making it we did somewhat more accurately determine the matter For by applying ice and salt to the outside of the vessel we found that the included air was contracted from 1965. spaces to which the Cold of the ambient air had reduc'd it into 1860. spaces so that the Circumposition of ice and salt did as much nay somewhat more condense it after the mere Cold of the external air had contracted it as far as it could then the bare though intense Cold of the ambient air could condense it at first and the greatest degree of adventitious Cold we were able to give by the help of nature or of art did not make the air expos'd to it lose a full tenth part of its former Dimensions on which occasion it may not be unworthy observation That there is no greater Disparity betwixt the proportion in which the Cold was able to condense the Air and that wherein the Cold was able to expand water 10. This is all that at present I think fit to say concerning the interest that Winds may have in the Temperature of the Air. And therefore I will now proceed to those other particulars wherewith I not long since said that I intended to close up this Section and I might on this occasion subjoyn many things but partly haste and partly other considerations will confine me to those that relate to the effects of Cold upon the Air in a more general way 11. And first we will observe that Cold may hinder in an almost incredible measure the warming operation of the Sun upon the Air not only in the hottest part of the Day for that may sometimes happen even in our Climate but at several times of the Day even in the heat of Summer 12. I remember I once accidentally met with an intelligent and sober Gentleman who had several times sail'd upon the frigid Zone and though an intervening accident separated us so suddenly that I had not opportunity to obtain from him the resolution of above two or three questions yet this I learned of him belonging to our present purpose That by the help of a Journal he kept he call'd to mind that upon the coast of Greenland he had observ'd it to snow all Midsummer night which affirmation of so credible a person imboldens me to add some other relations which I should else have scrupled at 13. Mr. Logan an English Merchant that Winter'd at Pecora one of the Northern Towns of Muscovy relates that being there at a great Salmon-fishing there hapned about the close of August which in many Countries is wont to be the hottest time of all the year so strong a Frost which lasted till the fourth day That the Ozera was frozen over and the Ice driving in the River to and again broke all the Nets so that they got no Salmon no not so much as for their own Victuals 14. Captain G. Weymouth mentions that in July though he was not near the Latitude of Nova Zembla much less of Greenland yet sailing in a thick fog when by reason of the darkness it occasioned he thought good to take in some of his sails when his men came to hand them they found their Sails Ropes and Tacklings so hard frozen that it did says he seem very strange unto us being in the chiefest time of Summer 15. In the fifth Voyage of the English to Cherry Island which lies betwixt 74. and 75. degrees of Latitude they observ'd that the wind being at North-east upon the 24. of July It freez'd so hard that the Ice did hang on their 〈◊〉 And in the seventh Voyage which was made three years after to the same Island they mention that on the 14. of July the wind being Northerly they had both snow and frost 16. The next thing that we shall take notice of is the degree of Cold which the Efficient causes of that Quality whatever they be are able to produce in the air but of this
weight before they were so and kept in a pair of good Scales fasten'd to a frame in some quiet place well fenc'd from the Sun would by the cold of the Air in freezing weather be kept for any considerable time without a sensible diminution of weight but an unexpected thaw hindered us from seeing the success of what we design'd of this nature both as to Eggs and also some other Bodies For if the Experiment were very carefully tri'd upon a competent variety of them it might possibly assist us to guess especially in Camphire and some other easily exhalible bodies what interest Cold may have in suppressing or diminishing the expiration of their Effluvia 7. But to return to the weight of Bodies frozen and unfrozen we attempted to discover somewhat about it by several ways according as the differing accommodations we were furnish'd with permitted And of these trials I will mention four or five as well of the less as of the more accurate as my memory or Notes supply me with them 8. One of the less Accurate ways we imployed to try whether ice in which according to the Atomists great store of these frigorifick Corpuscles must be wedged would not upon their expulsion or recess leave the water lighter then was the ice was that which follows wherein to hasten the Experiment we mingled a little salt And though we foresaw there would be a difficulty from the Adhaesion of the vapors of the external Air to the outside of the glass we were to employ we thought that inconvenience might be remedied by well wiping off the frost or dew from the outside of the glass till it were clean and dry The event of the trial we find succinctly set down among our Notes as follows A single vial sealed up with ice and salt being wiped dry and weighed was found to weigh four ounces four drachms and a half when it was quite thawed it was found to weigh somewhat more then a grain less then its former counterpoise But more accurate and satisfactory Trials about this matter I find thus set down in one of my papers 9. We took a vial more thin then those that are commonly us'd that of the Aggregate of that and the Liquor the glass might make so much the lesser part This vial was furnished with a somewhat long neck which at the flame of a Lamp was drawn by degrees slenderer and slenderer that being very narrow at the Top it might the more readily and conveniently be seal'd notwithstanding the waters being in it then we almost fill'd it with that Liquor I say almost because a competent space ought to be left unfill'd to allow the water swell'd by glaciation room to expand it self This vial with the liquor in it was plac'd in a mixture of snow and salt after our usual manner and when the glass appear'd almost full of ice it was taken out and nimbly clos'd with Hermes's seal presently after this was weigh'd in a pair of very good Scales and the vial together with the contain'd liquor amounted to 〈◊〉 38. gr ss which yet was not all ice because these things could not be done so nimbly but that some of the ice began to thaw before we were able to dispatch them quite the vial thus seal'd being remov'd and suffered for two or three hours to thaw when the ice was vanish'd we weigh'd again the seal'd glass in the same Scales and found that it weigh'd as before at least if there were any difference it seem'd to weigh a little more But this Increment that amounted not quite to ½ a grain might easily be attributed to some difference in the weights and grains themselves wherein 't is not easie to find a perfect exactness or to some little unheeded moisture that might adhere to some part of the vial 10. And because it may be wished that as this Experiment shews the weight of Ice resolv'd into water to be the same with that of the solid ice so we had tri'd whether the weight of water congeal'd into ice would be the same with that of the former fluid water we will subjoyn what immediately follows in the same paper in these words 11. We took a seal'd vial very thin that it might be lighter but not so large as the other by about a third as amounting in the lately mention'd Scales but to 〈◊〉 〈◊〉 gr 41. when we had seal'd it up with the water in it This vial we plac'd as we had done the other in a mixture of snow and salt freezing it warily lest being seal'd it should break then we remov'd it into the same Scales to try whether it had got any weight by the suppos'd subingression of the Atoms of Cold which many learned men take to be the efficients of Congelation but it either weighed just as before or if there were any difference it seem'd to have lost ¼ of a grain Being suffer'd to thaw and put into the same Scales again it weigh'd just as much as it did when frozen though the weights were numerically the same and about ⅛ would sway the Scales or at least be sensible upon them But note that I was careful this last time to wipe the outside of the glass with a linen cloth because I have observ'd according to what I elsewhere deliver that in case ice be any thing hastily thaw'd it may produce a dew on the outside of the glass as I suspected that even the warm Air might in some measure do in this and if it had not been for this suspition some adhering dew that I was thereby enabled to detect and wipe off before I put the vial into the Scales might easily have impos'd upon us 12. These Trials I presume may give some satisfaction about the inquiry for the resolving whereof I thought fit to make them 13. But I was also desirous to see whether any difference as to weight would be produc'd by freezing and thawing if I may use those expressions in this case Iron Stone Wood or the like solid and permanent Bodies which I intended to have exactly weigh'd before and after their being expos'd to the Air and also after the frost was gone and all this against Counterpoizes not expos'd to so great a Cold would discover any sensible alteration as to weight that might safely be ascrib'd to the Cold. And though Avocations and the negligence of one that we imploy'd kept us from bringing the matter to such an issue as was desired yet the Trials seem'd not altogether irrational since we have formerly made it probable and have since met with fresh instances to confirm it that even Stones and Metals may resent some change of Texture by the operation of some degrees of Cold. And indeed induc'd by such considerations of that kind as seem'd the least doubtful I remember I sometime made several experiments of the weight of some metals and stones both before and after they had been much expos'd to a more vehement Cold then would
ascribes to the resolv'd ice may have proceeded from that which would not have been taken notice of by an ordinary Experimenter For as I not long since intimated I have sometimes purposely and sometimes by chance by thawing ice in clos'd vessels somewhat hastily produc'd a copious dew on the outside of the vessels which dew as being made by the condens'd vapours of the ambient Air ought to be wip'd off before the vessel be put into the scales to weigh the melted ice And 't is possible also that Helmont may have err'd in the manner of weighing his Lagena whatever he mean by it it being usual even for learned men that are not vers'd in Statick's to mistake in Experiments which require that things be skilfully and nicely weigh'd How far this excuse may be appli'd to a late Commentator upon Aristotles Meteors who says he tri'd that water frozen is heavier then unfrozen being a stranger to that Authors writings I shall not consider only whereas Helmont and He seem to agree very little in their Affirmations it will be perhaps more difficult to accord them then to determine by the help of our formerly register'd Experiments what may be thought of both their Relations Yet I shall add on this occasion That if I had not devis'd the above mention'd way of freezing water by Art in Hermetically seal'd glasses I should have found it difficult to reduce what is affirm'd by Manelphus which I then dreamt not of to an accurate Experiment for though I had imploy'd a seal'd glass which I have not heard that he or any other has yet made use of to that purpose yet if I had in that vessel expos'd the water to be frozen the common way 't is odds though it be not absolutely certain that the water beginning as 't is wont to congeal at the Top the Expansion of the subsequently freezing water would break the glass and so spoil the Experiment And for the same reason I have sometimes in vain attempted to examine the weight of water frozen by nature according to her wonted method in open vials And if insteed of glasses you make use of strong earthen vessels there is danger that something may be imbib'd or adhere to the porous vessel and increase the weight and by some such way or by some mistake in weighing 't is very probable Manelphus may have been deceiv'd which I am the more inclin'd to think if we suppose him a sincere writer not only because of some things I have taken notice of about congelations made in earthen vessels but because when I have instead of an earthen made use of a metalline pottinger both which sorts of vessels have in common this inconvenience that their ponderousness makes them less fit for accurate Scales there appear'd cause to suspect either that our Author did not use metalline vessels or which I rather suspect that he wanted skill or diligence in weighing For as I find no intimation of his having imploy'd any peculiar or artificial sort of vessels so if he us'd such as we have newly been speaking of and had weigh'd them carefully I cannot but think that instead of finding the ice heavier then the water 't was made of he would have rather found it lighter For I remember that having once expos'd all night a pottinger almost full of common water to an exceeding sharp Air and having caus'd it the next morning to be brought me when the liquor was throughly frozen I found it to have lost about 50. grains if I misremember not of its former weight and though this event were consonant enough to my conjectures yet for greater certainty I repeated the Experiments another 〈◊〉 night with this new caution that the pottinger and water together with the counterpoise were kept suspended in the Scales to be sure that no effusion of any part of the water in carrying it abroad to the open Air should be made without being taken notice of but the next morning somewhat late the vessel with the contain'd water now congeal'd appear'd to have lost about 60. grains and with the like success the Trial was reiterated once more and that in weather so sharp that I am not apt to think the water expos'd by Manelphus began to freez sooner then ours But the event was not unexpected for besides that I consider'd that in these kind of Experiments part of the water notwithstanding the exceeding coldness of the Air must in all likelihood fly away before the surface of it began to be congeal'd I judge it not improbable that not only the fluid part but even that which was already congeal'd might continually lose some of its Corpuscles and by their recess lose also somewhat of its weight And least these conjectures should seem too too unlikely 't will not be amiss to add in favour of the first of them that having purposely provided a large Pewter Box with a cover to screw on it and having fill'd it almost full of water I say almost because if the vessel had been quite full the congealing cold might have burst it and carefully weigh'd the Aggregate of both which amounted to 〈◊〉 〈◊〉 gr 11. whereof the vessel weigh'd 〈◊〉 〈◊〉 and gr 8. we expos'd the water after the Top of the pot was screw'd on to hinder the Avolation of it to the freezing Air all night and the next morning found it frozen from the top to the bottom though not uniformly and perfectly but found not one grain difference betwixt its present and its former weight And as for the second conjecture newly propos'd though it may seem somewhat strange yet it is confirmable by this Experiment that having plac'd divers lumps of solid ice in a Pottinger which together with them weigh'd a pound consisting of 16 〈◊〉 and having exposed these things in the same scales wherein they were weigh'd to the free Air on a very frosty night we found the ice to have lost the next morning 24. grains of its weight and the weather continuing so cold that it froze hard all day long in the shade I gave order to have it kept out of the Sun in the same scales during all that time and a good part of the following night and then weighing it the second time found that the whole decrement of weight did now amount to five grains above two drachms though the weight of the ice without the pottinger were but about seven ounces and when we had kept about 13. ounces of ice in a very frosty night expos'd to the cold Air it had lost as early as the next morning a good deal above two drachms of its former weight But these Statical observations have perhaps already but too much swell'd this Appendix Title XXI Promiscuous Experiments and Observations concerning Cold. 1. I Hope it will not be imagined that I have such narrow thoughts of the subject I treat of Cold as to believe that I have compriz'd under those few Titles prefix'd to the
one fill'd up after the same manner to make the Experiment the more satisfactory But though he could not procure it yet the success was not unwelcome because it was manifest that there were cracks in the Iron in one place conspicuous and in others easily discoverable by blowing into the barrel and putting on the outside of the suspected parts either spittle or some fit liquor whose agitation plainly disclos'd the egress of the wind and there appear'd small cause to doubt but that these cracks were produc'd by the operation of the cold since not only the Smith was a skilful man in his trade and one that I us'd to imploy about Instruments and also the barrel had been sometimes kept many hours fill'd with water without appearing other then very stanch but which is the considerablest circumstance the night before the frost as I lately noted was not able to make the water break out at any of these clefts though it were able to force it self a way out at the screw in spight of all the care we had taken to make it go close I have only this circumstance to add about this matter that when by thawing one part of the ice some pieces of the rest were got out of the barrel all I took notice of appear'd to be full enough of Bubbles but yet such as seem'd lesser then ordinary whether they were so by chance or were determined to be so by the resistence or compression which the freezing water found upon its endeavouring to expand it self in the barrel Appendix to the XVII Title LOng since the writing of the foregoing Section meeting with a passage in Bartholinus where he vouches Cabaeus for the Experiment of congealing water without limiting it to any season of the year by putting Salt 〈◊〉 into it and shaking it strongly I was thereby confirmed that I was not mistaken in supposing that Gassendus mention'd in the former Section did not exclude that corporal and visible Nitre out of the number of the grand efficients of congelation For Cabaeus having publish'd his comment upon Aristotles Meteors whence this experiment is taken by Bartholinus before Gassendus publisht his Book 't is probable that he as well as others borrowed the Experiment from him and Cabaeus as Bartholinus quotes him prescribes the putting the Salt-petre its self into water which being a while put into a brisk motion will after some agitation not only refrigerate that water but bring it to a true and proper congelation Wherefore suspecting that this relation wherein Bartholinus says he will believe him without an oath may have given rise to the opinions and affirmations of those ingenious writers that have since ascrib'd such wonderful coldness to Nitre and finding in Bartholinus that Cabaeus's proportion betwixt the Nitre and the water was that of 35. to a 100. that is almost as one to three I thought it very well worth while to make Trial of an Experiment which seem'd to me little less unlikely then considerable I took then a pound of good Salt-petre and near 3. pound of common water to observe the more narrowly Cabaeus's proportion these being put into a large new Pipkin were kept constantly and nimbly stirr'd about sometimes by me sometimes by one or other of my Domesticks relieving one another when they were weary but though the mixture was with a kind of broad glass spattle kept in a brisk motion that for the most part was 〈◊〉 the manner of a whirle-pool and sometimes a more confus'd agitation and though we kept it thus stirring for almost an hour and a half till we saw no likelihood of effecting any thing by trying our selves any further yet not only we could not perceive that any Atom of true ice was produc'd whereas according to our Authors we might have expected a true and perfect congelation of all or the greatest part of the water but we did not find that there was so much as any freezing of the vapours on the outside of the vessel and for this reason we thought 〈◊〉 about the same time to try the Experiments by another kind of Agitation and mixing two ounces of Salt-petre with about six of water in a conveniently siz'd vial we did several of us successively vehemently shake the vial too and fro till we were almost tyr'd but neither this way was there produced the least ice within the glass or the least congelation of the vapours of the Air on the outside of it 'T is true that when so great a proportion of Salt-petre began to be dissolv'd in the Pipkin the water had a sensible increase of coldness which afterwards seem'd to diminish when once the Nitre was dissolv'd but not to mention that if I much mistake not we have observ'd the water to be refrigerated when upon the dissolution of common salt multitudes of actually cold and solid Corpuscles came to be every way dispers'd through it this coldness produc'd by the Nitre was very far short of the degree requisite to congelation for to satisfie my self that my sense did not misinform me I took a good seal'd Weather-glass of about ten or twelve inches long and immersing it into the cold mixture of Nitre and Water I observ'd the tincted spirit of Wine in the stem to descend not inconsiderably and when I perceived that degree of cold to have wrought its effect I remov'd the Thermoscope into a vial fill'd with common water about which I had caus'd to be plac'd a mixture of beaten ice and salt to 〈◊〉 the contained water in which the ball of the Instrument being plac'd the spirit of Wine hastily descended two or three inches below that place at which it stood when 't was remov'd out of the Nitrous solution And for further satisfaction removing the Thermoscope once again into that solution the spirit of Wine in the stem was hastily impell'd up as if the bubble had been put into warm water And once more the Weather-glass being remov'd into the formerly mention'd 〈◊〉 water the tincted liquor began to fall down hastily again and within a while subsided almost into the bubble whereupon to avoid injuring the instrument we thought fit to take it out so that upon the whole matter if the learned Cabaeus were not deluded by mistaking some Crystals of Nitre which I have observ'd easily to shoot again in water that has been 〈◊〉 with it for true and proper ice I cannot but wonder at his assertion and must take the liberty to think my self warranted by so many Harmonious Trials as I have found unfavourable to the suppos'd supremeness of Cold in Salt-petre to retain my former opinion about it till more succesful Experiments withdraw me from it 'T is a receiv'd Tradition among the Water-men and many others that the Rivers if not Ponds also are frozen first at the bottom and begin to thaw there But though I find this opinion to be in request not only among English Water-men but among the French too yet I think it
not find that his great earthen pots which are made up with as little water as is possible are deservedly famous for their durable Texture had not that Texture alter'd and impair'd by very piercing frosts he assur'd me that if he did not take care to keep the frost as they speak from getting into them those great and solid vessels wherein he us'd to keep his glass in fusion would in the fire scale or crack and perhaps fly and become unserviceable no less then some weeks sooner then if they had never been impair'd by the frost And when I inquired whether also glass it self would not be much prejudiced thereby he affirmed to me that oftentimes in very hard frosts many glasses that had continued intire for many weeks for that circumstance I was sollicitous to ask about would as it were of their own own accord crack with loud noises But whatever prove to be the issue of such Trials it will not be amiss to confirm the Phaenomenon it self by the testimony of an illiterate but very experienc'd French Aurhor who on a certain occasion tells us as I also take notice in another Treatise That he knows the stones of the mountains of Ardenne famous enough in France are harder then Marble and yet the inhabitants of that Countrey do not draw them out of the Quarry in winter because they are subject to the frost And it has been divers times seen that upon thaws the rocks without being cut have fallen down and kill'd many But it may yet seem far more unlikely that frosts should get into mettals themselves and yet having ask'd the newly mention'd Polonian whether he had observ'd any thing of that kind he answer'd that he had often by drawing out his sword and pulling out his pistols when he had been long in the field and came into a hot room found them quickly almost whitened over by a kind of small hoar frost But whether this were as he conceiv'd any thing that was drawn out of the Steel and setled on the surface of it I want circumstances enough to make me willing to determine But if we will credit Olaus Magnus it must be confess'd that considerably thick pieces of Iron and Steel it self will in the Northern Regions be render'd so brittle by the extreme frost that they are fain to temper their instruments after a peculiar manner his words which being remarkable I forbear to alter are these Videntur praeterea ferrei ligones certa ratione fabricati quia his spissa atque indurata glacies caeteris instrumentis ferreis non cedens facilius infringitur dum aliae secures chalybe permixtae in vehementi frigore ad solum glaciei vel virentis arboris ictum instar vitri rumpuntur ubi ligones praedicti sive ferreae hastae fortissimi manent Which testimony notwithstanding what some have written to this Authors disparagement does not seem to me at all incredible For I remember that even here in England I have had the curiosity to cause trials to be made in very frosty weather whereby if an expert Smith I then us'd to imploy did not gratis deceive me in the Irons I imploy'd that 〈◊〉 may by such degrees of cold as even our Climate is capable of be rendered exceeding brittle as he several times affirm'd to me that there are some kinds of iron which he could hammer and turn as they phrase it cold in open weather which yet in very hard frosts would become so brittle as by the same way of working easily to break if not to flye asunder And this he affirm'd both of Iron and Steel of which latter mettal another very skilful workman whom I also consulted certifi'd the like but though this disagreed not with trials purposely made on Iron rods had inform'd me yet presuming that in such a nice piece of work as a spring some further satisfaction about this matter might be obtain'd I inquired of a very dexterous Artificer that was skill'd in making springs for others whether or no he found a necessity of giving springs another temper in very frosty weather then at other seasons and he answered me that in such 〈◊〉 if he gave his springs the same temper that he did in mild and open weather they would be very apt to break And therefore in very sharp seasons he us'd to take them down lower as they speak that is give them a softer temper then at other times which as it makes it probable that the cold may have a considerable operation upon bodies upon which most men would not suspect it to have one so that discovery may afford a hint that may possibly reach further then we are yet aware of touching the interest that cold may have in many of the Phaenomena of nature I should here subjoyn that in prosecution of what is deliver'd in the XX. Section about the weight of solid bodies that I there wish'd might be expos'd to a congealing Air I did cause some Trials of that kind to be made in a very frosty night especially with Bricks but something that happened to the only Scales I then had fit for such an Experiment made me doubt whether some little increase of weight that seem'd to be gain'd by congelation were to be reli'd upon though there did not appear any hoar frost or other thing outwardly adhering to which the effect could be ascrib'd It is a Tradition which the Schools and others have receiv'd with great veneration from their Master Aristotle that hot water will sooner freez then cold but I do not much wonder that the learned 〈◊〉 as I find him quoted by Bartholinus should contradict this Tradition though he be himself a commentator upon that Book of Aristotle wherein 't is deliver'd For I could never satisfie my self that there is at least with our water and in our Climate any truth in the Assertion though I have made trial of it more ways then one but it may very well suffice to mention a few of the plainest and easiest Trials with whose success I am well satisfi'd as to the main as the Reader also will I doubt not be though not having for want of health been able to have so immediate an inspection of these as of the rest of my Experiments I was sometimes fain to trust the watchfulness of my servants whom I was careful to send out often to bring me word how long after the first freezing of the cold water it was before the other began to be congeal'd We took then three pottingers as near of a size as we could and the one we fill'd almost to the top with cold water the other with water that had been boil'd before and was moderately cool'd again and the third with hot water these three vessels were expos'd together in the same place to the freezing Air. In the Entry of one of the Trials I find that being all three put out at half an hour after eight of the clock That the
pottinger that contain'd the cold liquor began to freez at ¼ after ten That which contain'd the water heated and cool'd again began to freez ¾ past ten And that which contain'd the hot water at half an hour after eleven and somewhat better So that though all froze within the compass of two hours yet the cold water began this time to freez an hour and a ¼ sooner then the hot These pottingers were earthen but I elsewhere made the Trial in others of mettal and there also the cold water began to freez both before that which had been heated and cooled again and long before the hot Another time I measured out the water by spoonfuls into pottingers not having then by me any fit Scales to weigh it to be the more sure that the quantities of water should not be considerably unequal and then also the cold water froze a considerable while before the hot But my usual jealousie in the making nice Experiments tempting me to inquire whether the water in some of the former Trials had not been heated in a stone Bottle not a Skillet it was confess'd that it was so but that the bottle us'd to contain nothing but Beer and had been wash'd before-hand And though I did not think that the bottle could have any considerable influence on the Experiment yet least it should be suspected that the scalding water mighr have imbib'd some spirituous parts remaining yet among the minute dregs of Beer in the pores of the bottle for the greater security I caus'd the water to be heated in a Skillet and because in one of the Trials made in a Village where we had not choice of pottingers the cold water chanc'd to be put into one that afterwards seem'd less then that wherein the hot was expos'd I did this very day repeat the Experiment by putting cold water into a somewhat larger pottinger heating the other water in a Skillet and the event of the Trials is this That the cold water being put out with the rest at ¾ after 6. began to freez somewhat before ½ after 7. The water heated and cool'd again began to freez ¾ after 7. And having these frozen waters a pretty while by me I sent in for my own further satisfaction for the hot water and found it not to be in the least frozen at half a quarter after 8. So that supposing it to continue half a quarter of an hour longer before the beginning of its congelation it was twice as long ere it began to freez as the cold water had been By which we may see how well bestow'd their labour has been that have puzled themselves and others to give the reason of a Phaenomenon which perhaps with half the pains they might have found to be but Chymaerical I have been the more circumstantial in setting down these Trials that I may express a civility to so famous a Philosopher as Aristotle and also because Artificial Congelations which we can commonly best command and which we have the oftenest us'd about our other Experiments are not so proper for this For having formerly had the curiosity to take two pipes of glass made of the same Cylinder that they might be of equal bore and having seal'd each of them at one end and having fill'd both to the same height and then stirr'd them too and fro together in a mixture of beaten ice water and salt which mixture I make use of for the effecting sudden Congelations I found both waters to freez too quickly to make a notable disparity in the length of times that they remain'd uncongeal'd And we will not on this occasion omit one Phaenomenon afforded us by these Trials because it may admonish men how cautious they ought to be in making nice Experiments For having once made the formerly mention'd Trial with glass pipes that were but 〈◊〉 as not exceeding the 〈◊〉 of a mans fore-finger and having for greater caution put the hot water first into one glass and then into another we found one time that the hot water froze first and wondering at it we examin'd the glasses and perceiving one of them to be more Conical or acuminated where it had been seal'd up then the other it seem'd probable and afterwards appear'd true that the water in this acuminated part being suddenly frozen by reason of the slenderness of the glass there promoted and accelerated the Congelation of the rest so that whether it were the cold or the hot water that was put into that pipe it would thereby gain a manifest advantage In the foregoing Experiments made in pottingers I made use not only of cold and hot water but of water that had been heated and cool'd again though not reduc'd to its full pristine coldness to prevent the Objections of some that might pretend that such water would have frozen sooner then Cold which yet would not salve the common opinion which specifies not such water Postscript ANd it seems that such Cautions as I have been mentioning are not altogether useless For accidentally casting my eye upon the Circulus Pisanus of Berigardus upon Aristotles Meteors I somewhat wonder'd to find that an Author who is look'd upon to be a great adversary of Aristotle except in his dangerous and ill-grounded conceit of the eternity of the world and some other erroneous opinions does yet indeavour to justifie Aristotle by affirming that his Experiment will succeed if by heated water we understand that which having been heated is suffered to cool again till it be reduc'd to the temper of other water which was not heated For this refrigerated water he says he has found to congeal much sooner then the other water but this I confess I am very unapt to believe For having divers times caus'd cold water to be expos'd to the Air in frosty weather with that which had been heated and cool'd again and having set sometimes one of my Domesticks sometimes another to watch them the events did very much disfavour the assertion of our Author though care was had of the circumstances most considerable in such an Experiment as the matter size and shape of the vessels the equal degree of cold in the two several parcels of water into both which I sometimes dipp'd my finger to judge of them before they were expos'd and the place in which they were put both together to be frozen But for further satisfaction we elsewhere took two pottingers bought purposely for the making of Experiments of the same size and shape and in the same shop one of these we almost fill'd with cold water out of a glass wherein we mark'd how high that water reach'd that by filling the same glass to the same height with the refrigerated water we might be able to measure out the same quantity into the other pottinger This done I appointed one whose care I had no reason to distrust to examine the tempers of the several waters with a more then ordinarily sensible Weather-glass as a far safer
Criterion then the bare touch to judge of the coldness of liquors these being reduc'd to the same temper were expos'd to a very sharp Air and there watch'd by the person whom being not well and unable to support such weather my self I appointed to attend the Experiment and he according to direction finding them begin to freez as 't were at the very same time brought me in the two pottingers in each of which I saw the beginnings and but the beginnings of congelation where the upper surfaces of the waters were contiguous to the containing vessels so that having made this Experiment with much greater exactness then probably Berigardus did or for want of such instruments as I us'd could make it I cannot but suspect supposing the common waters he and I us'd to be of the same nature that he was either negligent or over-seen in affirming that heated and refrigerated water will cool so much sooner as he would perswade us then other And as I am not convinc'd by experience that it will freez sooner at all so till he have better made out the reason he seems to give of the Phaenomenon I must question whether he rightly ascribe after Cabaeus if I much misremember not the congelation of water to a certain Coagulum distinct from the cold spirits that plentifully mingle with the water which Coagulum it seems for his style is not wont to be very perspicuous that he would have to consist of certain dry Corpuscles no less necessary to conglaciate water then Runnet to curdle Milk And for what this Author says that he must have imploy'd boiling or scalding water who affirms it to be less congealable then other that mistake may be sufficiently disprov'd by the several above recited Trials wherein we found water moderately refrigerated to freez much later then cold and whereas Berigardus intimates that the person whoever he be that he dissents from does unskilfully suppose warm salt-water to be the less dispos'd to congelation for being salt our Author is therein also mistaken for though it be true what he alledges that salt outwardly appli'd promotes the congelation of water yet that dissolv'd in water it has a contrary effect may appear by the familiar observation that Sea-water is much more difficult to be congeal'd then fresh water and to show that 't is not a property of Sea-water but a water impregnated with common Salt I have several times tri'd that a strong solution of such salt in ordinary water will not at all be congeal'd by the being expos'd to the Air even in very sharp frosts as may be easily collected from some of the Experiments mention'd in the former part of this Book Another particular there is about the use of Allume in reference to freezing in this often cited passage of Berigardus which I might here examine if my hast and my indisposedness to ingage in a controversie of small moment did not injoyn me to defer it till a fitter occasion To confirm the power ascrib'd in the VI. Section to cold as to the long preservation of bodies from corruption 't will not be amiss to add these two remarkable passages the latter of which affords a good instance of the improvement that may be made of some degrees of cold to the uses of humane life The first observation is afforded us by some of our Countrey-men in a Voyage extant in Purchas where the writer of it speaks thus Of the Samojeds whose Countrey he visited Their Dead they bury on the side of the hills where they live which is commonly on some small Islands making a pile of stones over them yet not so close but that we might see the dead Body the Air being so piercing that it keepeth them from much stincking savour so likewise I have seen their Dogs buried in the same manner The other observation is given us in the description of Iceland made by one that visited it to be met with in the same Purchas's Collections where among other things he gives us this Account which if I mistake not I have had confirm'd by others of their strange way of ordering and preserving their Fish Having taken them they pluck out the bones and lay up their bowels and make Fat or Oyl of them They heap up their Fish in the open Air and the purity of the Air is such there that they are hardned only with the Wind and Sun without Salt better surely then if they were corned with Salt And if they kill any Beast they preserve the flesh without stinck or putrefaction without Salt hardned only with the Wind. I know not whether 't will be worth while to add to the fifth and sixth Numbers of the VII Title that for further confirmation of our opinion that 't is not Natures abhorrencie of a Vacuum but the distension of the water that breaks glasses when the contain'd liquors come to be congeal'd I did on set purpose fill several vials some at one time and some at another to the lower parts of their necks most of which were purposely made long with common water and though they were all left unstopp'd that the external Air might come in freely to them yet not only one of them that I stirr'd up and down in a mixture of beaten ice salt and water was hastily broken upon the congelation of the contain'd water but several others that were expos'd to be frozen more leisurely by the cold Air only were likewise broken to pieces by the expansion of the freezing water as appear'd both by the gaping cracks and also by this that the ice was considerably risen in the necks above the waters former stations which had been noted by marks before and if it had been more easie for the included water to make it self room either by stretching the glass or rather leaving the superficial ice congeal'd at first in the neck or by both those ways together then to break the vessel the vial would probably have remained intire I say probably because I am not sure that there may not sometimes intervene in these Experiments somewhat that may need further observation and inquiring For as it seems that what I have been lately saying may be confirmed by an unstopp'd vial which was expos'd at the same time to congelation with this success that without breaking the vial the water was frozen and the ice in the neck impell'd up a good way above the height at which the liquor rested before it began to congeal so on the other side I remember that I have sometimes had a good store of liquor frozen in a vial without breaking the glass though a vial were stopp'd as if the difference that I have on other occasions observed betwixt glasses whereof some are very brittle and others more apt to yield might have an influence on such Experiments or that some peculiar softness or other property of the ice that afforded me my observation or else some other thing not yet
taken notice of were able to vary their success In confirmation of what is delivered in the VII Section about the expansion of water by freezing I shall add that having caus'd some strong glass-Bottles of a not inconsiderable bignéss to be fill'd with a congealable liquor excepting the necks which were fill'd with Sallet oyl I observ'd that in a somewhat long and very sharp frost the contained water was so far expanded by congelation that it not only thrust up the corks but the cold having taken away the defluency of the oyl that liquor together with the water that could no longer be contain'd in the Cavities of the glasses being as it seem'd frozen as fast as it was thrust out of the neck there appear'd quite above the upper part of the Bottles Cylinders of divers inches in height consisting partly of concreted oyl and partly of congeal'd water having on their tops the corks that had been rais'd by them It is a Tradition very currant among us that when Ponds or Rivers are frozen over unless the ice be seasonably broken in several places the Fishes will dye for want of Air. And I find this Tradition to be more general then before I made particular inquiry into it I knew of For Olaus Magnus mentions it more then once without at all questioning the truth of it but rather as if the general practise of the Northern Nations to break in divers places their frozen Ponds and Rivers were grounded upon the certainty of it In the twentieth Book which treats of Fishes after having spoke of the reasons why the Northern Fishermen imploy so much pains and industry to fish under the ice and having said among other things that the nature of the Fish exacts it he adds this reason that Nisi glacie perforata respiracula susciperent quotquot in flumine vel stagno versantur subito morerentur Another passage of the same Author and taken likewise out of the same 20. Book you may meet with in the Margent though in another place he seems to intimate another and not an absurd reason of the death of Fishes in Winter where advertising the Reader that Ponds and Lakes did generally begin to freez in October he adds that Fishes are usually found suffocated when the Thaw comes where veins or springs of living water do not enter by which passage he seems to make the want of shifted water cooperate to the suffocation of the Fishes And to the same purpose I shall now add that having inquir'd of a learned Native that had had about Cracovia whose Territory is said to abound much in Ponds whether the Polanders also us'd the same custome he answered me that they did and that sometimes in larger Ponds they were careful to break the ice in eight or ten several places to make so many either vents or Air-holes for the preservation as they suppos'd of the Fish And when I inquir'd of the often mention'd Russian Emperors Physician whether in Muscovy the frost kill'd the Fishes in the Ponds in case the ice were not broken to give them Air he answered that in ordinary Ponds it were not to be doubted but that in great Lakes he could not tell because the Fishermen use to break many great holes in the ice for the taking of the Fish For at each of these holes they thrust in a Net and all these Nets are drawn up together in one great breach made insome convenient place near the middle of the rest It appears then that the Tradition is general enough but whether it be well grounded I dare not determine either affirmatively or negatively till trial have been made in Ponds with more of design or of curiosity and watchfulness then I have known hitherto done men seeming to have acquiesc'd in the Tradition without examining it and to have been more careful not to omit what is generally believ'd necessary to the preservation of their Fish then to try whether they would escape without it Wherefore though for ought I know the Tradition may prove true yet to induce men not to think it certain till experience has duly convinc'd them of it I shall represent That as much as I have in other Treatises manifested how necessary Air is to Animals yet whether Fishes may not live either without Air or without any more of it then they may find interspers'd in the water they swim in has not yet that I know of been sufficiently prov'd For what we have attempted of that nature in our Pneumatical Engine whether it be satisfactory or not is not yet divulged And I remember not to have hitherto met with any writer except Olaus be construed to intimate so much that affirms upon his own observation that the want of breaking ice in Ponds has destroy'd all the Fish Besides that possibly in frozen Ponds there may be other reasons of the death of the Fishes that are kill'd if any store of them be so by very sharp frosts For who knows what the locking up of some kinds of subterraneal steams that are wont freely to ascend through water unfrozen may do to vitiate and infect the unventulated water and make it noxious to the Fishes that live in it perhaps also the excrementitious steams that insensibly issue out of the bodies of the Fishes themselves may by being penn'd up by the ice contribute in some cases to the vitiating of the water at least in reference to some sort of Fishes For being desirous to learn from a person curious of the ways of preserving and transporting Fish whether some Fishes would not quickly languish grow sick and sometimes dy out-right if the water they swam in were not often shifted he assur'd me that some kinds of them would and it has not yet that I hear of been tri'd whether or no though Ponds seldom freez to the bottom yet the water that remains under the ice in which it self some Fishes may be now and then intercepted may not even whilest it continues uncongeal'd admit a degree of cold that though not great enough to turn water into ice may yet be great enough when it continues very long to destroy Fishes though not immediately yet within a less space of time then that during which the surface of the Pond continues frozen But 't is not worth while to be sollicitous about conjectures of causes till we are sure of the Truth of the Phaenomenon and these things are propos'd not so much to confute the Tradition we have been speaking of as to bring it to a Trial which having no opportunity to make in Ponds I endeavour'd as well this Winter as formerly to obtain what information I could from Trials made in small vessels with the few Fishes I was able to procure And I shall subjoyn most of these Trials not because I think them very considerable but because they are for ought I know the only attempts of the kind that have yet been made To satisfie my self whether the ices denying
access to the Air was that which destroy'd Fishes in frozen Ponds I thought upon this Epedient I procur'd a glass vessel with a large belly and a long neck but so slender that it was only wide enough for the body of the Fishes to pass through and then having fill'd the vessel with some live Gudgeons and a good Quantity of water the neck of it was made to pass through a hole that was left or made for it in the midst of a metalline plate or wooden Trencher which could descend no lower then the neck because of the inferior part of the glass that would not suffer it and which serv'd to support a mixture of Ice or Snow and Salt which was appli'd round about the extant neck of the glass By this contrivance I propos'd to my self a double advantage the first that whereas in broad vessels 't is not always so easie as one would think to be sure that the surface of the water is quite frozen over in every part by this way I could easily satisfie my self by inverting the glass and observing that the ice had so exactly choak'd up and stopt the neck that no drop of water could get out not any bubble of Air get in and yet the Fishes had liberty enough to play in the subjacent water The other conveniency was that the frigorifick mixture being appli'd to the neck no water was congeal'd or extremely refrigerated but that which was contain'd in the neck so that there seem'd no cause to suspect that in case the Fishes thus debarr'd of Air should not be able to live in the water it was rather Cold then want of Air that kill'd them But though not having then been able by reason of a remove to prosecute these Trials to the utmost nor to register all the circumstances I shall not lay much weight upon it yet I remember that the included Fishes continued long enough alive to make me shrowdly suspect the Truth of the vulgar Tradition Another time being destitute of the conveniency of such glasses I caus'd some of the same kind of Fishes to be put into a broad and flat earthen vessel with not much more water then suffic'd perfectly to cover them and having expos'd them all night to a very intense degree of cold I found the next morning that some hours after day they were alive and seem'd not to have been much prejudiced by the cold or exclusion of Air. 'T is true that there was a very large moveable bubble under the ice but that seem'd to have been generated by the Air or some Analogous substance emitted out of the Gills or bodies of the Fishes themselves for that the surface of the water was exactly frozen over which does not in such Trials happen so often as one would think I found by being able to hold the vessel quite inverted without losing one drop of water And that this large bubble might possibly proceed from the Fishes themselves I was induc'd to suspect because having at different seasons of the year for divers purposes kept several sorts of Fishes and particularly Gudgeons for many days in glass vessels to satisfie my self about some Phaenomena I had a mind to observe I have often by watching them seen them lift up their mouthes above the surface of the water and seem to gape and take in Air and afterwards let go under water out of their mouthes and gills divers bubbles which seem'd to be portions of the Air they had taken in perhaps a little alter'd in their bodies And particularly in Lampries of which odd sort of Fishes I elsewhere make mention I have with pleasure both observ'd and show'd to ingenious men that being taken out of the water into the Air and then held under water again they very manifestly appear'd to squeez out and that not without some force at those several little holes which are commonly mistaken for their eyes numerous and conspicuous bubbles of Air which they seem'd to have taken in at their mouthes if not also at those holes But of these matters a fitter occasion may perhaps invite me to say more To return now to our Gudgeons I shall add that to satisfie my self further what cold and want of Air they may be brought to support I expos'd a couple of them in a bason to an exceeding bitter night and though the next day I found the ice frozen in the vessel to a great thickness and one of the Fishes frozen up in it there remaining a little water unfrozen the other Fish appear'd through the ice to move to and fro and the ice being afterwards partly thaw'd and partly broken not only that Fish was found lively enough but the other which I alone judg'd not to be quite dead though when the ice was broke it lay moveless did in a few minutes so far recover as to tow after it if I may so speak a good piece into which his tail remain'd yet inserted and though one of these and some other Gudgeons that had been already weakned by long keeping were once more expos'd in the Bason to the frost and suffer'd to lye there till they were frozen up yet the ice being broken in which they were inclos'd though their bodies were stiff and crooked and seem'd to be stark dead lying in the water with their bellies upwards yet one of them quickly recovered and the other not very long after began to show manifest signs of life though he could not in many hours after so far recover as to swim with his back upwards 'T is true that these Fishes did not long survive but of that two or three not improbable reasons might be given if it were worth while to name here any other then this that the ice they had been frozen up in or the violence that was offered them by the fragments of it when it was broken had wounded them as was manifest enough by some hurts that appear'd upon their bodies yet some other Gudgeons were irrecoverably frozen to death by being kept inclos'd in ice during if I misremember not the time three days And as for other Animals I caus'd a couple of Frogs to be artificially frozen in a wide mouth'd glass furnish'd with a convenient quantity of water but though they seem'd at first inclos'd in ice yet looking nearer I found that about each of them there remain'd a little turbid liquor unfrozen as if it had been kept so by some expirations from their bodies Wherefore causing either the same or two others for I do not punctually remember that circumstance to be carefully frozen and for a considerable while I found that notwithstanding the ice into which most part of the water was reduc'd not only one of them before the ice was broken appear'd to be perfectly alive but the other that was moveless and stiff and lying with the belly upwards in a Bason of cold water whereinto it was cast did in a very few minutes begin to swim about in it I
should have made more Trials at least if not also more satisfactory ones if I could have had Fishes and vessels and cold weather at command But upon the whole matter though the Tradition we have been examining may perhaps have some thing of truth in it yet it seems to deserve to be further inquired into both in reference to the truth of the matter of fact the death of Fishes in frozen Ponds and Rivers and in reference to the cause whereto that effect is imputed I met with an odd passage in Captain James's voyage which if it had been circumstantially enough set down might prove of moment in reference to the weight of bodies frozen and unfrozen and therefore though I would not build any thing on it yet I shall not omit it The ninth says he we hoisted out our Beer and Cydar and made a Raft of it fastning it to our shore-Anchor The Beer and Cydar sunck presently to the ground which was nothing strange to us for that any wood or pipe-staves that had layen under the ice all Winter would also sinck down so soon as ever it was heav'd over board About the duration of ice I forgot through hast to add a relation of Capt. James whereby it may appear That though Wine abounds with very spirituous and nimble parts whence it resists congelation far more then water yet if even this liquor came once to be congeal'd the ice made of it may be very durable For he sets down in his Journal that when he came to his Ship again he found a But of Wine that had been all the Winter in the upper deck to continue as yet all firm frozen though it were then the moneth of May. When I treated of the great proportion in some pieces of ice that were aground instead of taking notice of the great piece of ice mention'd by Gerard de Veer to be 52. fathom deep the passage that was to be transcrib'd was this other hard by which contains two examples of towers of ice where the extant part reach'd upwards more then half as much as the immersed part reach'd downwards We saw says he another great piece of ice not far from us lying fast in the Sea that was as sharp above as if it had been a Tower whereunto we rowed and casting out our lead we found that it lay 20. fathom fast on the ground under the water and 12. fathom above the water We rowed to another piece of ice and cast out our Lead and found that it lay 18. fathom deep fast on the ground under the water and 10. fathom above the water That snow lying long and too long on the ground does much conduce to the fertilizing of it is a common observation of our Husbandmen And Bartholinus in his Treatise of the use of snow brings several passages out of Authors to make it good to which I shall add the testimony of our learned English Ambassador Dr. Fletcher who speaking of the fruitfulness of the soil and hasty growth of many things in the great Empire of Russia gives this account of it This fresh and speedy growth of the Spring there seemeth to proceed from the benefit of the snow which all the Winter time being spread over the whole Country as a white robe and keeping it warm from the rigour of the frost in the Spring time when the Sun waxeth warm and dissolveth it into water doth so throughly drench and soak the ground that it is somewhat of a slight and sandymold and then shineth so hotly upon it again that it draweth the herbs and plants forth in great plenty and variety in a very short time As we made some Trials to discover whether congelation would destroy or considerably alter the odors of bodies so we had the like curiosity in reference to divers other qualities not only those that are reputed manifest as colours and tastes the latter of which we sometimes found to be notably chang'd for the worse in flesh congeal'd but also those that are wont to be call'd occult and among the qualities of this sort I had particularly a mind to try whether the purging faculty of Catharticks would be advanc'd or impair'd or destroy'd by congelation and for this purpose I caus'd to be expos'd thereunto divers purging liquors some of a more benigne and some of a brisker nature and that in differing forms as of syrup decoction infusion c. But for want of opportunity to try upon the bodies of animals what change the cold had made in the purging liquors it had congeal'd I was unable to give my self an account of the success of such Experiments only since in some of these Trials I had a care to make use of Cathartick liquors prepar'd by fermentation which way of preparing them is it self a thing I elsewhere take notice of as not unworthy to be prosecuted I shall add on this occasion that fermentation is so noble and important a subject that the influence of cold upon it may deserve a particular inquiry And I am invited to think that that influence may be very considerable partly by my having observ'd upon a Trial purposely made both that Raisins and water with which I was us'd to make Artificial Wines did not in many days whilest the weather was very frosty so much as manifestly begin to ferment though the water were kept fluid and partly by my having observ'd that Beer will continue as it were new and be kept from being as they call it ready to drink much longer then one would readily suspect if very frosty weather supervene before it have quite finished its fermentation insomuch that an experienc'd person of whom I afterwards inquir'd about this matter assur'd me that Beer not duly ripe would not sometimes in five or six weeks of very frosty weather be brought to be as ripe as in one week of warm and friendly weather But we have a nobler instance to our present purpose if that be true which I learn'd from an intelligent Frenchman whom I consulted about this matter For according to this experienc'd person the way to keep Wine in the Must in which state its sweetness makes it desir'd by many is to take newly express'd juice of Grapes and having turn'd it up before it begins to work to let down the vessels which ought to be very carefully clos'd to the bottom of some deep Well or River for six or eight weeks during which time the liquor will be so well setled if I may so speak in the constitution it has so long obtain'd that afterwards it may be kept in almost the same state and for divers moneths continue a sweet and not yet fermented liquor which some in imitation of the French and Latins call in one word Must. And how by the help of Cold well appli'd some other juices that are wont to work early and to be thereby soon spoil'd may be long kept from working the Reader may perchance learn in
another Treatise to which such matters more properly belong 'T is known that the Schools define cold by the property they ascribe to it of congregating both Heterogeneous and Homogeneous things I thought it not amiss to attempt the making some separations in bodies by the force of Cold. For if that hold true in this climate which has been observ'd by Travellers and Navigators in Northern Regions that men may obtain from Beer and Wine a very strong spirit and a phlegme by congelation it seems probable that in divers other liquors the waterish part will begin to freez before the more spirituous and saline and if so we may be assisted to make divers separations as well by cold as by heat and dephlegme if I may so speak some liquors as well by congelation as by distillation but I doubt whether the ordinary frosts of this Countrey can produce a degree of cold great enough to make such divisions and separations in bodies as have been observ'd in the more Northern Climates For though having purposely hung out a glass-bottle with a quart of Beer in it in an extraordinarily sharp night I found the next morning that much the greatest part of the Beer being turn'd into ice there remain'd somewhat nearer the middle but nearer the bottom an uncongeal'd liquor which to me and others seem'd stronger then the Beer and was at least manifestly stronger then the thaw'd ice which made but a spiritless and as it were but a dead drink yet in some other Trials my success was not so considerable as some would have expected For having put one part of high rectifi'd spirit of Wine to about five or six parts if I misremember not of common water and having put them into a round glass and plac'd that in beaten ice and salt though the mixture were in great part turn'd into ice yet I could not perceive that even two liquors so slightly mingled were any thing accurately severed from one another although once to enable my self the better to judge of it the spirit of Wine I imploy'd was beforehand deeply tincted with Cochinele and therefore I the less wonder that in Claret Wine I could not make any exact separation of the red and the colourless parts However I thought it not amiss to try how far in some other liquors this way of separating the waterish and more easily congealable part from the rest would or would not succeed And I remember that a large glass vessel wherein spirit of Vinegre was exposed to the cold a considerable part was turned into ice whose swimming argued it to be lighter then the rest of the liquor but though I put some of this ice in a glass by it self to examine by its weight and taste when thaw'd how much it differ'd from the uncongeal'd part of the spirit my hopes were disappointed by a misfortune which was not repaired by my exposing afterwards a smaller quantity of spirit of Vinegre to the Nocturnal Air for that proved so cold that the whole was turned into ice wherefore I must reserve for another opportunity the prosecuting that Experiment as also the trying whether a separation of the Serous or the Oleaginous parts of Milk may be effected For though once the frost seem'd to have promoted a separation of Creme notwithstanding that heat also may do it and though another time there seem'd to be another kind of divulsion of parts made by congelation yet for want of leisure to prosecute such Trials they prov'd not satisfactory no more then did some attempts of the like nature that I made upon blood by freezing it But notwithstanding these discouragements I resolv'd to try what I could do upon Brine For calling to mind the Relations mentioned in the XV. Title and elsewhere which seem to argue that in some cases the ice of the Sea-water may being thaw'd yield fresh water and being the more inclin'd to think it worth Trial by a Physician I since happened to discourse with about this matter who affirm'd to me that sailing along the coast of Germany he had taken out of the Sea ice that being thaw'd he found to afford good fresh water I began to consider whether we might not by cold free salt water at some seasons of the year from a great deal of the phlegme which 't is wont to cost much to free them from by fire and other means For a little help towards the diminution of the fresh water is look'd upon as so useful an Experiment by many that boil salt out of the salt springs that in some Countries that are thought the skilfullest in that trade they make their salt-water fall upon great bundles of small brush-wood that being thereby divided and reduc'd to a far greater superficies there may in falling through some of the purely Aqueous parts exhale away wherefore dissolving one part of common salt in 44. times its weight of common water that it might be reduc'd either exactly or near to the degree of saltness that has been by several writers observed in the water of our neighbouring Seas and having likewise caus'd another and much stronger Brine to be made by putting in to the water a far greater proportion of salt for so there is in many of our salt springs we expos'd these several solutions to the congealing cold of the Air in frosty weather where the last mention'd solution being too strongly impregnated with the salt continued some days and nights altogether uncongeal'd but that weaker solution which emulated Sea water being expos'd in a shallow and wide mouth'd vessel that shape being judg'd the most proper we could procure for our design the large superficies that was expos'd to the Air did as we expected afford us a cake of ice which being taken off and the rest of the liquor expos'd again to the Air in the same vessel we obtain'd a second cake of ice and taking the remaining which seem'd to be indispos'd enough to congelation we found that by comparing it with that which was afforded us by the first cake of ice permitted to thaw there appear'd a very manifest difference betwixt the water whereinto the ice was resolv'd scarce tasting so much as brackish whereas the liquor that had continued uncongeal'd was considerably salt in taste And if I had had the conveniency of examining my self these two liquors Hydrostatically as I was fain to have them examin'd by another I doubt not but by their weight I should have discovered precisely enough the difference between them which the person I employ'd found to be considerable and consequently should have been assisted to make an estimate of the advantage that might be afforded by the operation of the cold towards the freezing of the Brine from its superfluous water But though I had not a quantity of ice great enough to satisfie me whether that little brackishness of taste I have mention'd proceeded from some saline Corpuscles that concurr'd to the constituting of the ice it self or did only adhere
to find them every time the same that he had found them once And to intimate That by the by to make several Trials in a short time and thereby produce variety of figures 't is not an ill expedient to expose the liquor one would have congeal'd in very shallow vessels or if it be put into other vessles to leave it but of very little depth And if the vessel it self be highly refrigerated either by the cold Air or by having salt and ice applied to the outside of it the congelation may succeed much the more nimbly so that within a short while the same liquor being divers times thaw'd and frozen again may possibly exhibit variety of figures And the production of ice may be also much accelerated by dipping into the liquor one would have congealed the convex surface of some glass or other smooth body that will not imbibe water for thereby the depth of the liquor will be exceedingly extenuated and how much such a thinness or want of depth may dispose a liquor to be speedily penetrated and congealed by the cold may be guessed by what is above delivered in the Section out of Olearius of the way of multiplying ice in Persia by making water thinly diffuse it self over a plate of ice or some other aptly figured and very cold body In confirmation whereof I will add on this occasion that I have seen a pair of Stairs on which though they were situated near to three Chimneys commonly furnished with fire almost all the day long the water that was imployed to wash them being thinly spread with a Mop would presently congeal though they assur'd me it was hot when 't was begun to be laid 〈◊〉 and cover the Stairs with glossy filmes of ice And I have likewise observed in a very sharp night that the water which dropp'd down from the nose of a Pump was so well congealed as 't was sliding away that the ice thus arrested in its passage in which 't will easily be granted that it spreads it self very thinly had rais'd a kind of icy pyramid of a considerable bigness and height I forgot to mention in due places and therefore think fit to take notice of it here that when I was considering of the ways whereby it might be manifested to those that want nice 〈◊〉 or distrust their skill to use them whence that ice comes that appears on the outside of frozen Eggs put to thaw in cold water I found it somewhat difficult to pitch upon such a liquor as I desir'd For if common water be the liquor imploy'd it may be said that it affords the matter whereof the ice in question is made and if I imploy'd liquors that were spirituous or saline it might be pretended that the frost as they speak did indeed come out of the frozen Egg though the shell did not appear cas'd with ice because as fast as the frost came to the outside of the Egg it was resolv'd by the spirituous or saline Corpuscles of the liquor wherefore as an expedient I resolved to make use of oyl of Turpentine as a liquor which I had found incongealable by the greatest cold I had observed in our Climate and which yet as may appear by the third Paragraph of the XVI Title was more indispos'd then common water it self to thaw any icy Efflorescence that might be emitted by the Egg. But the Experiment was tri'd without uniformity in the successes For the first time I put a frozen Egg into oyl of Turpentine I did not observe that any ice was produced on the outside neither was the event differing when another time I put two frozen Eggs together into a small vessel full of that oyl though to refrigerate the liquor the vessel was for a while placed upon a mixture of salt and ice and though also the Egg-shells at their gaping cracks produced by congelation discovered that the contained liquor was well frozen I intended to prosecute the Experiment another time wanting ice to do it then because that once when during the Trial I was hindred from watching it one of my Domesticks whom I ordered to look after it assured me that the Egg that was put to thaw in the oyl of Turpentine had there obtained ice on the outside of it which I should readily have believed upon the score of a like observation I had made my self in two Eggs that were frozen to the bottom of the vessel wherein they had been put to thaw were it not that one or both of them had been by a mistake dipt in water before they were put into the above mentioned oyl Some Readers may have expected to find among the examples recited of the influence of cold upon the Air that strange story which is related by the learned Josephus Acosta of the mountains of Pariacaca which he several times traversed but besides that I have delivered a great part of it already in another Treatise I was loath to say more till I had leisure which I have not now to discuss the scruples that I have not so much about the matter of fact as about the cause which perhaps may be something besides cold But since I have mention'd this XVIII Section I will here take notice of what I then intended but forgot to set down namely That to the instances alledged to show the coldness of regions not to be always proportionate to their greater and less vicinity to the Pole we may add a memorable one afforded us by a Countrey so well known to many of us as New England where though the Winters are so long and bitter as we have formerly related out of Mr. Woods's Prospect of that Countrey which has been confirm'd to me by an American Physician that liv'd there yet that Region which is so very much colder then ours is in many places no less then a 10. or 11. degrees remoter from the Pole I shall add to the same XVIII Section that as to the Experiment I there mention'd concerning Winds and which I associate with the testimony of the newly named Mr. Wood I find that the season of the year and some other circumstances may vary it more then one would easily have suspected For though I faithfully recited the Phaenomena as I then and that sometimes with witness took notice of them yet some moneths after and in other weather having occasion to repeat the former part of that Experiment I was somewhat surpriz'd at the success For coming to blow upon the Ball of a seal'd Weather-glass which though in its kind very tender might be probably presumed to be less so then a Thermoscope made with a pendulous drop of water such as that mention'd in the forecited Paragraph I found that if I continued to blow any thing long and briskly the highly rectified spirit of Wine which circumstance I therefore name because possibly the nature of That may somewhat alter the case would sometimes manifestly enough subside And in that Paragraph of the
having imagin'd that Cold might afford a hopefuller way then for ought I know any man has us'd of bringing this controversie to the dicision of an Experiment I made that attempt that is mention'd in the XII Title in prosecution of which as soon as I could procure some though but some of the accommodations which I long wanted I made an Experiment which I shall subjoyn because though it be not so considerable as with better implements I could have made it yet the way I chose has as I partly intimated elsewhere these two advantages that the force imploy'd to compress the Air is both very great and very gradually and slowly appli'd and that the vessel will not like those that have been hitherto made use of give any passage through its pores to water though violently compress'd We took then a Round Ball of glass furnish'd with a moderately long Pipe and having fill'd it with water till the liquor reach'd within some inches of the top it was Hermetically seal'd up and then the water by a mixture of beaten ice and salt was made to freez from the bottom upwards that without breaking the glass the unfrozen water by the expansive endeavour of that which was freezing might be impell'd upwards and so at once both compress the Air and be press'd upon by it having by this means condens'd the Air as far as we thought safe to do in a glass that was not strong we cropt of the small Apex of the glass and immediately the compress'd Air flew out with a great noise and that part of the Pipe which was unfill'd with water was fill'd with smoak that made it look white and great store of little bubbles hastily ascended from the lower parts of the water to the upper where most of them quickly broke in such a way as put me in mind of what usually happens upon the opening of vessels that contain'd bottled Beer But that which was principally to be noted was this that besides the bubbles or froth the water it self at least supposing that no little unheeded bubbles that did not quite emerge could sensibly contribute to its height immediately ascended in the Pipe about ¾ of an inch which having carefully mark'd the first and second stations with a Diamond on the outside of the glass 't was easie for us to measure I have elsewhere propos'd a suspicion that in the attempts that had been till then made to compress water the condensation in case there were really any might perchance proceed from the compression of the Aerial particles that I have shown to be wont to ly dispers'd in the pores of common water But though the considerable expansion of water notwithstanding the breaking of the bubbles in our present Experiment seems manifestly to argue that this could be but a concurrent cause if it had any sensible effect at all of our Phaenomena yet I dare not absolutely rely even upon an Experiment that seems so cogent till I have satisfi'd my self that no springiness which I have sometimes suspected might be in the ice had any interest in the produc'd effect and that the great pressure of the forcibly condens'd Air did not make the glass it self stretch or yield For if it were able to do so then the parts of the violently distended glass upon the removal of the forcible pressure of the Air which must cease upon the breaking of the Hermetical seal returning to their former straitness below will make the water ascend somewhat higher in the pipe But though I could not procure glasses as well very thick as conveniently shaped wherewith to examine this suspicion which I would likewise have tri'd by the bulk of the glass in water before and after the letting out of the compress'd Air yet because most Readers will probably think so much caution more then necessary I shall add that if I had not wanted conveniencies and had not had mischances the Experiment would in likelihood have been advanc'd especially care being taken that the Air left in the pipe should be well refrigerated before its being seal'd up as we sometimes did by ice and salt applied in a perforated Box to the outside lest part of its spring should depend upon an evanid degree of heat upon which account the pipe ought beforehand to be drawn so slender that the glass may be melted together in a trice For though for want of strong glasses the best sort of instruments to seal up such with the success was not still so considerable as I hop'd for yet as 4. or 5. other Trials made as well with another liquor as with water did exhibit a manifest intumescence of the liquors without computing the froth produc'd at the top so in the Experiment lately mention'd if we had judg'd them strong enough to indure such a compression of the included Air as we have often made on other occasions the effect would probably have been much more considerable For though the difference betwixt the length of the same water compress'd and uncompress'd amounted to an Aqueous Cylinder of ⅜ of an inch in height yet the Air that made this compression of the water was it self reduc'd but from 8. inches to 5. so that it took up almost half its former room whereas we have sometimes reduc'd it to an 18. or 20. part thereof If I had been accommodated with one of my Pneumatical Engines I should have tri'd whether water being first carefully freed from the latitant Air in the exhausted Receiver and then compress'd after the manner hitherto recited the event of the Trial would have been considerably varied I might add as other Phaenomena of our Experiment that when we broke off the seal'd Apex of the glass before the included Air was much compress'd there neither 〈◊〉 be any great noise made nor any considerable froth produc'd at the top of the water and that having had the curiosity to repeat the Experiment in one of the same glasses 〈◊〉 had been 〈◊〉 us'd and with the same 〈◊〉 that had been already compress'd in it we found that upon the breaking off the Hermetical seal the second time the water did nevertheless ascend in the Pipe betwixt ⅛ and ¼ part of an inch And to these particulars I could both add other circumstances that I took notice of in the same Experiment and subjoyn many other Experiments and Observations but that I am already tyr'd And though I have not found Cold to be a subject over-fruitful in Experiments Pleasing and Curious yet now I am grown somewhat acquainted with it I find it may suggest so many other new ones that since the Barrenness of my Theme will not easily put a period to this Treatise 't is fit that now at length I should let my Weariness and want of Leisure do it FINIS AN Examen of Antiperistasis AS It is wont to be Taught and Prov'd Themistius Carneades Eleutherius Themistius 1. AS for Antiperistasis the Truth of it is a thing so conspicuous and
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
Cellars and other subterraneal cavities where consequently they produce such a heat as to those that come out of the cold air may be very sensible And the rather because whilest men by the coldness of the season are more then ordinarily careful to stop up the passages at which the external air may get in they do though designlesly stop up the vents at which the subterraneous exhalations might get out And to shew you that this last circumstance is not impertinently taken notice of I shall tell you that a very grave Author having occasion to mention Cellars relates it as a practise in divers houses of a Town where he had been to keep vents in their deep Cellars which in the Summer were from time to time opened partly to keep the places sweet and wholsom and partly to let out the warm Exhalations that would else hinder their liquors from keeping so fresh and well And these steams were affirm'd to have been several times taken notice of to ascend visibly into the free air like a smoak which several Phaenomena and particularly what I formerly related of the hot fumes that manifestly ascended out of the great Groove in the Hungarian Mine may keep us from thinking incredible 40. And now by what I have hitherto discours'd I have made way for the solution of a Phaenomenon that is wont to be much urg'd in favour of Antiperistasis namely the smoaking of water that is drawn in frosty weather out of deep Wells and Springs 41. But first I must advertise you that 't is improperly enough that some urge for Antiperistasis such examples as the strange Spring near the Temple of Jupiter Ammon which Lucretius and others have observed to have been exceeding cold in the day time and as hot at night for not now to examine whether this story be not fabulous or might not be ascrib'd to some crafty trick of the Idolatrous Priests that had a mind to impose upon Alexander as well as others and procure an admiration to the place I consider that this and other the like cases such as are the Springs mentioned in the Islands of Maldiviae by Pyrard a French Author that was shipwrack'd and liv'd long in those parts must be referred to the peculiar Nature of the Springs or some other hidden cause since if the water of them were but ordinary and the Phaenomena were the effects of Antiperistasis it might justly be expected that the like should happen in all Springs or at least in very many which that it does not common experience shows us And I would say that this might be the case of the Spring you mention out of Captain James's Voyage but that besides that he does not say expresly that it was frozen in July but only that then it afforded him no water which might happen upon divers other accounts And besides that 't is manifest that in far hotter Countries where the excessive heat of the Air might more intend the subterraneal cold if Antiperistasis could do it there is no talk of any such degree of cold in Summer as to freez the Springs besides this I say there seems to be through some mistake or other a contradiction in the relation it self since in the same Voyage speaking of the same month of December he expresly says that their Well was then frozen up so that dig as deep as they could they could come by no water And he complains on that occasion of the unwholsomness of melted snow-water 'T is true that he soon after mentions a Spring that he found under a hills side which did not so freez but that he could break the ice and come to it but by his very sending far from his house to that Spring it appears to have been a Consequence and therefore a Proof of the uselesness of his Well in December as his affirmation that it continued all the year so as to be serviceable when the ice was broken shows that the Antiperistasis did not freez it up in Summer And having cleared my self of such a Testimony of this ingenious Navigator as would appear very illustrious if there had been no mistake about it I shall not scruple to add that the late publisher of the Latin Description of Denmark and Norway informs us that in or near that little Danish Island 〈◊〉 wherein the famous Tycho built his Urani-Burgum there is one Spring among many ordinary ones that even in the coldest Winter is never frozen which subjoyns my Author does in these regions exceeding rarely happen to be found Olaus Magnus also relates that in another part of the King of Denmarks Dominions namely near Nidrosia one of the chief Cities of Norway there is a Lake that even in that Northern Region never freezes And the learned Josephus Acosta mentions that among a very great number of hot Springs to be met with in Peru At the Baths which they call the Baths of Ingua there is a course of water which comes forth all hot and boiling and joyning unto it there is another whose water is as cold as ice He adds That the Ingua or the Peruvian Emperor was accustomed to temper the one with the other and that it is a wonderful thing to see Springs of so contrary qualities so near one to another These relations as I was saying I scruple not to mention though at first sight they may seem to disfavour my cause For by these and some others it may appear that Springs may obtain very peculiar and strange qualities from the nature of the places whence they come or through which they pass or from some other causes that are as hidden from us as the originals of these rare waters And this being once prov'd who knows what interest such causes as we are strangers to may have in some Phaenomena that are wont to be wholly ascrib'd to the heat and cold of the superficial part of the ground and what influence they have upon many other Springs besides those above mentioned some of which that are very deep may rise from the warm region of the Earth where they may be affected by the place as both these and others may be by Mineral juices and steams such perhaps as we know nothing of though we well know that some of them that are saline without being at all sensibly hot will powerfully resist congelation 42. But having hinted thus much on this occasion I shall now proceed to consider The smoaking of waters drawn from deep places in frosty weather and show that it does not necessarily conclude such water to be warmer in Winter since that effect may proceed not from the greater warmth of the water in such weather but from the greater coldness of the Air. For we may take notice that a mans breath in Summer or in mild Winter weather becomes very visible the cold ambient Air nimbly condensing the fuliginous steams which are discharg'd by the Lungs and which in warmer weather are
then in Summer For the instances produced by Carneades seem plainly enough to manifest the contrary and my own observations made in a Cellar with a seal'd Weather glass do keep me from dissenting from Carneades as to that point I would therefore make a distinction of subterraneal places for some are deep as the best sort of Cellars other deeper yet as the Hungarian Mines mention'd by Carneades out of Morinus and some again are but shallow as many ordinary Cellars and Vaults of these three sorts of subterraneal Places the deepest of all do not as far as the Authority of Mineralists above alledg'd may be reli'd on for I am yet inquiring further grow hot and cold according to the several seasons of the year as the vulgar doctrine of Antiperistasis requires but are continually hot The shallower sort of subterraneal places though by reason of their being fenc'd from the outward Air they are not so subject to the alterations of it whether to heat or cold as open places are yet by reason of their vicinity to the surface of the Earth they are so far affected with the mutations which the outward Air is liable to in several seasons of the year that in Winter though they be warm in respect of the colder Air abroad yet they are really at least some of them as far as I have tri'd colder in very cold weather and less cold in warm weather And in this opinion I am confirm'd by two things the one that having purposely inquir'd of the Polonian Nobleman mentioned by Carneades whether he had observ'd in his Country that in sharp Winters small Beer would freez in Cellars that were not very deep but would continue fluid in those that were he assured me he had taken notice of it The other thing is the Confession of the Anonymous Jesuite lately mention'd who acknowledges that he found but little difference between the Temperature of the water in the Well he examin'd in Summer and in Winter though it were a considerably deep one and adds a while after that at Florence where the subterraneal Vaults are shallower the Air is observ'd to be colder in Winter then in Summer though at Rome in their deep Cellars the contrary has been found So that the lower-most sort of subterraneal cavities being for ought appears perpetually hot and the upper or shallower sort of them being colder not hotter in cold weather then 't is in warm 't is about the Temperature of the middle sorts of them such as are the deeper and better Cellars that the question remains to be determined And thus much of my first consideration The next thing I shall offer to be consider'd is this That 't is not so easie a matter as even Philosophers and Mathematicians may think it to make with the weather-glasses hitherto in use an Experiment to our present purpose that shall not be liable to some exception especially if the Cellars or Wells where the observations are to be made be very deep For the gravity of that thick and vapid subterraneal Air and the greater pressure which the Air may there have by reason of its pressing according to an Atmospherical Pillar lengthened by the depth of the Cellar or Well may in very deep Cavities as well alter the height of the water in common Weather-glasses as heat and cold do and so make it uncertain when the mutation is to be ascrib'd to the one and when to the other or at least very difficult to determine distinctly what share is due to the pressure and what to the temperature of the Air. And this uncertainty may be much increas'd by this more important Consideration that not only in places where the heights of the Atmospherical Cylinders are differing the pressures of the Air upon the stagnant water in the Weather-glasses may be so too but even in the self same place the instrument remaining unmov'd the pressure of the Atmosphere may as I have often observ'd hastily and considerably alter and that without any constant and manifest cause at least that I could hitherto discover so that the erroneous estimate that may be hereby suggested of the temperature of the Air can scarce possibly be avoided without the help of a seal'd Weather-glass where the included liquor is subject to be wrought upon by the heat and cold not pressure of the Air. So that to apply this to Zucchius his Experiment unless he had been aware of this and unless I knew that he had divers times made his observations with the assistance of a seal'd Weather-glass it may be suspected that he might accidentally find the water in his common Weather-glass for such a one it appears he us'd as probably knowing no other to be higher when he look'd on it in Summer then when he look'd on it in Winter not because really the subterraneal Air was colder in the former season then in the latter but because the Atmosphere chanc'd then to be heavier and when I remember in how few hours I have sometimes and that not long since observ'd the Quicksilver both in a good Barometer and even in an unseal'd Weather-glass furnished with Quicksilver to rise almost an inch perpendicularly without any manifest Cause proceeding from cold I cannot think it impossible that in long Weather glasses furnish'd only with water or some such liquor the undiscerned alterations of the Atmospheres pressure may produce very notable ones in the height of the water in such instruments But this is not all that a jealous man might suspect For Zucchius having for ought appears made his Observations but in one place we are not sure but that may be one of those whereof there may be many on which the subterraneal Exhalations have a peculiar and not languid influence as Carneades has towards the close of his Discourse made probable out of the Relations of Olaus Magnus and Martinius touching the great and sudden thaws that sometimes begin from the bottom and thereby argue their being produc'd by copious steams that ascend from the lower parts of the Terrestrial Globe which may be further confirm'd by what he formerly noted of the sudden Damps that happen in many Mines But that which is of the most importance about our present inquiry remains yet to be mentioned which is that having had the curiosity to inquire whether no body else had made Experiments of the same kind I find that the learned Maignan had the same curiosity that Zucchius had but with very differing success and therefore though this inquisitive person do admit in his Disputation about Antiperistasis a Notion that I confess I cannot approve since to ascribe as he does a fuga Contrarii to Cold and Hot spirits is in my apprehension to turn inanimate Bodies into intelligent and designing Beings yet he does justly and rationally reject with Carneades the vulgar doctrine of Antiperistasis and confirms his rejection of it by two Experiments For first he says that he found with a Thermometer that when
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
there is no probability that the ice should be generated according to the way propos'd by Mr. Hobs. For he will scarce prove nor is there any likelihood that a wind pierc'd the shell and closer coats of the Egg to get into the contain'd liquors and freez them and a more unlikely assertion it would be to pretend as he that maintains Mr. Hobs's doctrine must that so very little Air if there be any as is mingled with the juices of the Egg is by the Cold which is not wont to expand Air nor water till it be ready to make it freez turn'd into a wind subtile enough freely to penetrate the shell and coats of the Egg and great enough to diffuse it self every way and turn on every side the neighbouring water into ice and all this notwithstanding that not only it appear'd not by bubbles breaking through the water that there is any Adventitious Air that comes out of the Egg at all but that also supposing there were some such contain'd in the Egg yet what shadow of reason is there to conceive that the Air which was engag'd in and surrounded with the substances of the white and the yelk of the Egg must needs be a wind since according to Mr. Hobs that requires a considerable motion of most of the parts of the mov'd Air the same way and according to him also a body cannot be put into motion but by another body contiguous and mov'd 16. Sixtly Mr. Hobs does indeed affirm that all wind cools but is so far from proving that the highest degrees of Cold must needs proceed from wind that he does not well evince that all winds refrigerate Nor are we bound to believe it without proof since wind being according to him but Air mov'd in a considerable quantity either in a direct or undulating motion it does not appear how Motion should rather then Rest make Air grow cold For though it be true that usually winds seem Cold to us yet in the first place it is not universally true since some that have travelled into hot Countries and particularly the learned Alpinus have complain'd that the winds coming to them in the Summer from more torrid Regions have appear'd to them almost like the steam that comes out at the open mouth of a heated Oven And if Marcus Polus Venetus be to be credited for I mention his Testimony but ex abundanti the Southern winds near Ormus have been sometimes so hot as to destroy an Army it self at once And secondly even when the wind does feel cold to us it may oftentimes do so but by accident for as we elsewhere likewise teach the steams that issue out of our bodies being usually warmer then the ambient Air whence in great Assemblies even those that are not throng'd find it exceeding hot and I have several times observ'd a hot wind to come from those throngs and beat upon my face and the more inward parts of our bodies themselves being very much hotter then the ambient Air especially that which is not yet full of warm steams the same causes that turn the Air into a wind put it into a motion that both displaces the more neighbouring and more heated Air and also makes it pierce far deeper into the pores of the skin whereby coming to be sensible to those parts that are somewhat more inward then the Cuticula and far more hot the Air turn'd into wind seems to us more cold then the restagnant Air if I may so speak upon such another account as that upon which if a man has one of his hands hot and another not the same body that will appear luke-warm to this will appear cold to the other because though the felt body be the same yet the Organs of feeling are differingly dispos'd And to confirm this doctrine by an Experiment which has succeeded Often enough and need not succeed Always to serve our present purpose we will add that though Air blown through a pair of Bellows upon ones hand when 't is in a moderate temper will seem very cold yet that the ambient Air by being thus turn'd into wind does indeed acquire a relative coldness so as to seem cold to our senses but yet without acquiring such a cold as is presum'd may appear by this that by blowing the same air with the same Bellows upon Weather-glasses though made more then ordinarily long and by an Artist eminent at making them we could not observe that this winds beating upon them did sensibly refrigerate either the Air or the liquor Though 't is not impossible but that in some cases the wind may cool even inanimate bodies by driving away a parcel of ambient air impregnated with exhalations less cold then the air that composes the wind But this is not much if at all more then would be effected if without a wind some other body should precipitate out of the air near the Weather-glass the warmer Effluvia we have been mentioning especially if the Precipitating Body introduce in the room of the displaced Particles such as may in a safe sense be term'd Frigorifick 17. Seventhly Nor can we admit without a favourable construction Mr. Hobs his way of expressing himself where he says as we have lately seen that All wind cools or deminishes former heat For if we take heat in the most common sense wherein the word is used not only by other writers but also by Philosophers to make wind the adequate cause of cold it must in many cases do more then diminish former heat For water for instance that is ready to freez is already actually cold in a high degree and yet the wind if Mr. Hobs will needs have that to be the efficient of freezing must make this not hot but already very cold liquor more cold yet before it can quite turn it into ice 18. These things thus establisht it will not be difficult to dispatch the remaining part of Mr. Hobs his Theory of Cold for to proceed to his sixth Section we shall pass by what a Cosmographer would perhaps except against in his doctrine about the generation and motion of the wind upon the surface of the Earth and shall only take notice in the remaining part of that Section of thus much That the most of what Mr. Hobs here shews us is but that there is an expansion of the air or a wind generated by the motion and action of the Sun but why this wind thus generated must produce cold I do not see that he shews nor does his affirming that it moves towards the Poles help the matter for besides that we have shewn that wind as such is not sufficient to produce far less degrees of cold then those that are felt in many Northern Regions there must be some other cause then the motion of the air or steams driven away by the Sun to make bodies not in themselves cold for so they were suppos'd not to be when the Sun began to put them
in motion become vehemently cold in their passage For Mr. Hobs cannot as other Naturalists derive the coldness of freezing winds from the cold steams they meet with and carry along with them in their passage through cold Regions since then those steams rather then the wind would be the cause of that vehement coldness and so it might justly be demanded whence the coldness of those cold exhalations proceeds Besides that 't is very precarious and unconsonant to observation to imagine such a wind as he talks of to blow whenever great frosts happen since as we noted before very vehement glaciations may be observ'd especially in Northern Regions when the air is calm and free from winds 19. The account he gives in his seventh Section of turning water into ice is the most unsatisfactory I have ever yet met with for a good part of that Section is so written as if he were affear'd to be understood But whereas he supposes that by the indeavour of the wind to raise the parts of the water joyn'd with the indeavour of the parts of the water towards the Center of the Earth the uppermost parts of the water will be prest together and coagulated he says that which is very far from satisfactory For first ice is often produced where no wind can come to beat upon the uppermost parts of the water and to raise them and in vessels Hermetically seal'd which exactly keep out air and wind ice may be generated as many of our Experiments evince And this alone were a sufficient answer since the whole explication is built upon the action of the wind But this is not all we have to object for not to urge that he should have prov'd that the uppermost parts of the water must be raised in congelation especially since oyl and divers other liquors are contracted by it not to urge this I say what shew of probability is there that by the bare indeavour of the wind and the gravity of the superficiate parts of the water there should be any such forcible compression made as he is pleas'd to take for granted And yet this it self is less improbable then that supposing the upermost parts of the water to be pressed together that pressure is sufficient to coagulate as he speaks or rather congeal them into ice So bold and unlikely an assertion should at least have been countenanced by some plausible reason or an example in some measure parallel For I remember not any one instance wherein any degree of compression that has been imploy'd much less so slight a one as this must be considering the causes whence 't is said to proceed can harden any liquor into ice or any other hard body And in the Experiment we have elsewhere mentioned of filling a Pewter vessel with water and when 't is exactly clos'd compressing it by the knocks of a Hammer till the water be reduc'd to penetrate the very Pewter we found not that so violent a compression did give the water the least disposition to turn a hard body And as for the way Mr. Hobs assigns of Increasing the thickness of ice 't is very difficult to conceive how a cake of ice on the top of the water being hard frozen to the sides of the containing vessel and thereby severing betwixt the included water and the external air the wind that cannot come to touch the water because of the interposition of the hard and rigid ice should yet be able sometimes at the depth of nine or ten foot or much further to beat upon the subjacent water and turn it into ice And it is yet more difficult to conceive how the wind must do all this when as was lately noted the water does very often freez more and more downwards to a great depth in places where the wind cannot come to beat upon it at all And as to what Mr. Hobs further teaches that the ice must contain many particles of air receiv'd into it we have elsewhere occasion to show how 〈◊〉 he discourses about those Icy Bubbles 20. The reason he assigns of the freezing of water with Snow and 〈◊〉 does as little satisfie as the rest of his Theory of Cold. For not to mention that he affirms without proving it that Snow and Salt have in them a great deal of air it is very precarious to assert that this air must be prest out every way in wind which must rake the sides of the vessel for 't is strange that far more diligent observers then Mr. Hobs should take no notice of any such wind if any such wind there were but this is yet less strange then that which follows namely that this wind must so rake the sides of the vessel as to make the vessel by the same motion and action congeal the water within it For what affinity is there between a wind passing along the outside of a glass altogether impervious to it and the turning a fluid body included in that glass into a hard and brittle body The wind indeed may perhaps if it be strong a little shake or agitate the particles that compose the glass and those may communicate some of their motion to the contiguous parts of the water but why all this must amount to the turning of that water into ice is more I confess by far then I can apprehend Especially seeing that though you long blow upon a glass of water with a pair of Bellows where there is not an Imaginary wind as Mr. Hobs's but a Real and manifest one yet the water will be so far from being frozen that our formerly mentioned Experiments of blowing upon Thermometers make it probable that it will scarce be cool'd And if Sea-salt do contain so much air by vertue of which it as well as the Snow produces so intense a degree of Cold how chance that being resolv'd in a little water without Snow it does not produce at least a far greater degree of cold then we find it to do Besides in the Experiment we made and elsewhere mention of freezing water seal'd up in Bubbles though the Bubbles were suspended in other glasses whose sides no where touched them and the remaining part of whose cavities were fill'd some with air and some with unfreezing liquors what likelihood is there that Mr. Hobs's insensible Wind should be able to occasion so many successive Rakings through differing Bodies as there must be to propagate the congelative motion if I may so call it of the wind through the first glass to the included Air or Liquor and through that new Medium to the glass containing immediately the water and through that to the innermost parts of the seal'd up water And it might be further objected if it were worth while that Mr. Hobs does not so much as offer at a reason why spirit of Wine Aqua fortis or even Brine if it be of the strongest sort are not either by this mixture or here in England by the Wind in the open
Air turn'd into Ice as well as many other Liquors are 21. The reason why Cold is wont to be more remiss in rainy or cloudy weather then in that which is more clear is not better given by Mr. Hobs then by some others that have written before him for not to mention that I have seen great frosts and lasting enough in cloudy and sometimes very dark weather that which he talks of the winds being more strong in clear weather then in cloudy is of no great importance since common Experience shews that in clear weather the Air may be very cold and the frost very great where no wind is felt to rake as he would have it the superficies of the Earth Nor does experience bear witness to what he not warily enough pronounces that the less the wind is the less is the Cold. There are but two Phaenomena more which in this Section Mr. Hobs pretends to explicate The one is that in deep Wells the water does not freez so much as it does upon the superficies of the Earth But the reason of this we elsewhere take occasion to consider therefore in this place we need only note that Mr. Hobs has not rightly assigned it by ascribing it to the winds entring more or less into the Earth by reason of the laxity of its parts since besides that it is very improbable that the wind should not as he says it does not lose much of its force by entring into the Earth at its pores and other lesser cavities for that seems to be his meaning by the laxity of the Earths parts to so great a depth as water lies in several Wells subject to freezing besides this I say Experience teaches us that Wells may be frozen though their Orifices be well covered and the wind be thereby kept from approaching the included water by divers yards and very many Wells that are subject to freez when Northerly and Eastwardly winds reign will likewise be frozen in very cold Winters whether any wind blows or not 22. The other and last Phaenomenon Mr. Hobs attempts to explicate is That ice is lighter then water the cause whereof says he is manifest from what I have already shewn namely That air is receiv'd in and mingled with the particles of the water whilest it is in congealing But that this is not the true reason may be argued from hence that if a conveniently shap'd glass-vessel be fill'd top full with water and expos'd either unseal'd or seal'd to congelation the ice will have store of bubbles which at least in the seal'd vessel cannot by Mr. Hobs who will not affirm glass to be pervious to the Air be pretended to proceed from bubbles that got from without into the water whilest it was in congealing And we have sometimes had occasion to manifest by particular Experiments purposely made how little of Air there is even in those bubbles that are generated in ice made in vessels where the Air was not kept from being contiguous to the water 23. And thus have we gone through Mr. Hobs's Theory of Cold. In his Proposing of which we wish'd he had in Divers places been more Clear and in our cursory Examination of which we have seen that most of the particulars are either precarious or erroneous and were they neither yet the whole Theory would I fear prove very insufficient Since an attentive Reader cannot but have marked that this learned Author has past by far the greatest part even of the more obvious Phaenomena of Cold without attempting to Explicate them or so much as shewing in a general way that he had Consider'd them thought them explicable by his Hypothesis By which he that will fairly explain all the Phaenomena recited in the Notes we have been drawing together and which yet contain but a Beginning of the History of Cold shall give me a very good opinion of his Sagacity A Postscript THough the hast I am obliged to comply with keep me from annexing the Historical Papers wherewith I had thoughts to Conclude this Book concerning Cold yet since the Nature of the past Examen gave me but little Opportunity to teach the Reader any thing more considerable then that Mr. Hobs's Doctrine is Erroneous I am very inclinable to make him here some such little amends as the Time will permit for that Paucity of Experiments And therefore since in the last Section of the foregoing History upon occasion of an Experiment very Imperfectly and not intelligibly deliver'd by Berigardus I intimate my having elsewhere Plainly set down either the same he meant or one of that Nature and that with considerable Phaenomena unmention'd by him I chuse rather to borrow some Account of it from another Treatise to which it belongs then not gratifie some of the Curious to whom the Phaenomena I shew'd them of it seemed no less pretty then surprizing The way then that I us'd in making this Experiment may be gathered from the following directions Take of good unslak'd Lime three parts or thereabouts of yellow Orpiment one part of fair water 15. or 16. parts beat the Lime grosly and powder the Orpiment with care to avoid the noxious Dust that may fly up and having put these two ingredients into the water let them remain there for two or three hours or longer if needs be remembring to shake or stir the mixture from time to time By this means you will obtain a somewhat faetid Liquor whereof by warily Decanting or by Filtrating it the Clear part must be severed from the rest In the mean time take a piece of Cork and having lighted it so that it is kindled throughout remove it from the fire whilest 't is yet burning and by a quick immersion quench it in fair water And having by this means reduc'd it to a coal you may in case you have not err'd in the Operation by grinding it with a convenient Quantity of Gum-water bring it to the colour and consistence of a good black Ink that you may use with an ordinary Pen. Whilest these things are doing you may take what quantity you think fit of common Minium and two or three times its weight of spirit of Vineger which needs not be for this purpose much stronger then phlegm and to which even undistill'd Vineger may be a succedaneum and putting the powder and liquor into a glass Vial or any other convenient vessel let them infuse over hot Embers or in some considerably warm place for two or three hours more or less till the liquor have acquir'd a very sweet taste All things being thus prepar'd take a new 〈◊〉 at least a clean Pen and write with it some such thing as you either desire or need not fear to have read between if you please or which is safer Over the Lines which contain your secret and which are to be trac'd with the solution of 〈◊〉 for this Liquor if it be either well decanted or filtred
will be so clear that what is written with it by a new Pen will not be seen upon the Paper when it is dry Lastly when you would show the Experiment dip a small 〈◊〉 of Sponge or a Linnen-rag or for a need a little paper wreath'd in the water that was made with Lime and Auripigmentum and with this liquor which though it smell ill will look limpid and clear wiping over the Paper it will presently at once both wipe out or obliterate what was written with the black Ink and make all that was written with the invisible Ink though perhaps in the self-same Lines appear black so as to be very easily and plainly legible This is the way to which many years ago my Trials led me of making this odd Experiment For the performing whereof if any can propose a more Easie and Better way for I find by an Inquisitive Traveller that there are more ways then one I shall willingly learn it In the mean time the Reader may perceive that I did not causlesly intimate That the learned Berigardus though he would manifest a great thing in Philosophy by this Experiment did yet either not Understand himself that part of it he pretends to Teach or has omitted one of the main Ingredients of the water of Orpiment he speaks of For I did not find that even by a long Infusion nor by some Decoction of the Orpiment alone without the Quick-lime there would be produc'd a Liquor either obviously faetid or that would perform so much as a Less matter then what that which he mentions should And whereas he seems to commend this way though but between Lines written with common Ink for the writing of things one would not have to be discovered and though I have yet met with no body that having seen the Experiment is not of his mind yet I remember that when many years ago I was making Trials concerning the several ways of making invisible Inks my Conjectures led me to discover that I could very readily bring what was written with a solution of Minium to be Legible by the help of the fire as well as I could also detect by the same way several invisible Inks which are believ'd to require appropriated Liquors to make them Confess their secrets But I must reserve the Reflections and other particulars that relate to this Experiment for the Treatise to which it belong'd Only I will now add That besides the above-specified motives to communicate what I have at present witten of it I was the rather induc'd to do so because I had mention'd but not taught this Experiment in the History of Whiteness and Blackness and because also Berigardus is not the only Author of Note I have met with that having made particular mention of the Experiment has given the Curious but a Lame and unsatisfactory Account of it FINIS Philosophical Writings already publish'd by this Author NEw Experiments Physico-mechanical touching the Air 1660. publish'd about Midsummer Certain Physiological Essays written on several occasions 1661. in March The Sceptical Chymist 1661. in August A defence of the Doctrine touching the Spring and Weight of the Air against the Objections of Franciscus Linus 1662. in the Spring The usefulness of Experimental Philosophy 1663. in June Experiments and Considerations touching Colours 1664. in May. Such Philosophical Writings of the same Author as being occasionally mention'd here and there in the above-nam'd Books are not yet publish'd but though not absolutely promis'd by divers of the Curious expected THe second Section of the second part of the usefulness of Experimental Philosophy Two Essays concerning the Concealments and Disguises of the Seeds of Living Creatures Some Additional notes design'd by way of Appendix to the Physico-Mechanical Treatise Two Historical Dialogues one concerning Flame the other concerning Heat Hydrostatical Paradoxes made out by Physico-Mechanical Experiments An Essay of the Origine of Forms and Qualities Of the Production of Qualities manifest and occult by Art The Sceptical Naturalist being a Letter about the Imperfections of Natural Philosophy as we yet have it A Discourse of Improbable Truths AN ADVERTISEMENT THe Author of the following Discourse intending it should make a part of certain Considerations upon the four famousest Hypotheses or Opinions of the Nature and Cause of Cold which Considerations he thought fit to reserve for the latter end of the History of that Quality was invited to suppress it ever since the former part of the year that preceded the last And though this Discourse both for other Reasons and because he found it more ready and finished then some other Papers that belonged to the same part of the newly mentioned History comes abroad unaccompanied yet he judged it not amiss to intimate thus much That the Reader may be informed upon what Account Mr. Hobs's Opinions come to be examined in a Historical Treatise and may not wonder either to find that divers passages of It are omitted that are unfavourable enough to Mr. Hobs's Doctrine or to meet with in a Discourse postpon'd to the History of Cold some Experiments that seem to argue it to have been written before they were 〈◊〉 into the Order wherein they now appear To this I have nothing to add but that whereas through haste the Scheme referred to in the long citation out of Mr. Hobs's has not been added to the others that belong to this Book I am not much troubled at the Omission as also that in other Quotations the place is not always as well mentioned as the words because if any shall be found that after having considered what I urge against the Great but Imaginary Interest Mr. Hobs would ascribe to Winds whether he explicate their causes rightly or not in the Production of lesser degrees of Cold but how improbably soever of congelation it self shall think the sight of that Scheme of any Importance this Learned Mans Book De Corpore is in so many hands that any Reader that shall desire it may very easily have an opportunity to consult the Scheme in the particularly cited place An Account of Freezing made in December and January 1662. SInce the business of Freezing is obnoxious to many various contingencies I must necessarily premise these following circumstances that these experiments were made in very hard weather yet with some alternate relaxations the frost continuing above six weeks And the place I chose was in stone-windows exposed to the North and North-east winds and some upon the ground The vessels were Glass-canes of several bores earthen and pewter small pans and porringers spoons of pewter and silver glasses of various figures as Vials Cylindrical round and square flasques recipients boltsheads and some Conical ones Most whereof by the diversity of their figure their openness or closeness produce various effects in freezing as the following observations will shew The quantity also of the liquor exposed is to be considered for what will shew a small thin plate of ice in a small parcel
of some liquors will shew none in a greater The method I shall follow in delivering my observations shall be first to run over the various liquors or bodies whether fluid or consistent simple or compound c. used in this work Secondly what figures observable in those ices Thirdly some effects arising 〈◊〉 Fourthly some properties and qualities Fifthly some lets or helps both to freezing and thawing Sixthly some uses 〈◊〉 ice In pursuance of which particulars I had recourse to those ingenious 〈◊〉 of Mr. 〈◊〉 registred in your Cimelia and then to Bartholinus his late Book De Nive and to my own collected notes from various Authors adding whatsoever trials I thought meet And in all these I have barely set down matter of fact neither mentioning the Authors nor their errors which would have been both nauseous and tedious nor 〈◊〉 I endeavour to render a reason of the various 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 which cannot be done without a volume but shall leave that province to an Honourable person of this Society who hath had much experience and reflections on this subject And now to my task As to my first head of things used I shall begin with common water which I exposed in a triple 〈◊〉 in like quantities and in open 〈◊〉 viz. first cold secondly boiling hot thirdly an equal mixture of both the former The effect was this the cold was frozen in one hour the boiling hot in two hours and the mixt in hour 1 and ½ but with this difference that the cold did freez first at the top and sides and had a large thick crust before there was any shew of ice in the boiling hot but the mixt and boiling hot began to freez first at the bottom of the vessels and when the top was cold then it freezed there also leaving betwixt the bottom and top of the vessel a cavity for the water which in time was wholly converted to ice The same succeeded most manifestly in these waters powred on a smooth table where the cold water was presently frozen before the boiling hot water could become cold at the bottom Water exhausted of air in Mr. Boyles engine was frozen almost as soon as a like quantity expos'd in an open pan The ice whereof appeared white and to consist purely of bubbles The glass used was a four ounce round vial and a small Tube one foot long half filled with water Fair water wherein Arsnick had been infused eight moneths congealed much sooner then a like quantity of water into very white ice Solutions of all the sorts of Vitriols freezed sooner in pans and Tubes then water or any other solution of the other salts by much though that of Alume came very little short of it The ice kept both colour and taste upon the least touch of the tongue in all of them A solution of Alume did freez into an ice whiter then milk and stuck so close to the sides of the pan that it could hardly be separated from it this was the firmest ice offered to me in all my trials next to which in both these qualities were the Vitriols especially the Roman Sandever quickly freezeth Frit sooner then it and Kelp then them both all of them into lumps very white and consequently not Diaphanous Sal Armoniac shewed some variety in point of time for in the same pan quantity and place with the other salted waters 't would for the most part freez long after the former though once it did freez before them Common salt two drachms dissolved in four ounces of common water for that proportion I observed in all my solutions did in 30. hours space in the hardest season turn to pretty hard and white ice whereas the former solutions became so in two or three hours at the most A beer-glass was filled with stinking Sea-water full of salt which within 26. hours acquired at the top a plate of ice of the thickness of an ½ a Crown piece with few bubbles in it This tasted salt and stinking as before but being dissolved at the fire or thaw'd of its self the stinking taste was gone but the saltish continued The residue in the glass within four days the season continuing and plates taken off once in 24. hours was frozen throughout but that at the bottom of the glass seem'd to have a much brisker taste then that at the top neither was it so firm and friable as that I tried another beer glass with the same water which froze most part of it but the season continued not so constantly sharp so long together as in the former experiment and therefore I could conclude nothing therefrom But in small broad earthen-pans set in ice in 36. hours the same water became ice throughout and with the addition of a parcel of ice or snow much sooner Some water was impregnated with as much bay-salt some with as much Salt Petre some with as much Sal Armoniac as the water was capable to receive and neither of these did congeal with the highest degree of cold continued six days together A solution of salt of Tartar soon converted into ice but in much longer time then common water I observed that it began to freez in a Tube at the top bottom and sides first leaving the liquor in the middle unfrozen whereas other solutions and liquors congealed uniformly by descending or ascending or both at the same time from side to side through the middle of this I made but one Trial. Salt Peter required 28. hours in a very cold season and in that time became in the open pan a most pure white ice perfectly like Sal Prunellae which an Apothecary mistook it for This ice thrown into the fire after the aqueous humidity was evaporated did sparkle as that salt useth to do A strong Lixivium made hereof with an addition of Copperas or Alume singly or mixt set in snow and salt or snow alone was froze in one night Sal Gem alone of all the salts though snow and ice were mixed with it in great proportion and though the pan was set in salt and snow could not all that time be brought to congelation an odd experiment Phlegm of Vitriol did freez sooner then the solutions before mentioned Oyl of Vitriol begins congelation or coagulation rather near as soon as fair water A pretty large Tube was fill'd ¾ full with this oyl and about ¼ thereof was frozen the rest remaining at the bottom uncongealed This Tube was broken in the presence and by the command of this Honourable society the coagulated part whereof was tasted by many then present and concluded by all those that it was a strong Vitriolate taste This coagulated part was of a paler colour then the other and both these mixed and powred into a vial-glass heated it so hot that none there could hold it This coagulated part kept so in the air a week after all my other liquors had been thaw'd and would in probability have continued so much longer had not the
glass been broken I exposed another lesser Tube with the same oyl which became frozen throughout and required very much relaxation in the air to return to its former fluidity I had set a mark on these Tubes as on all the rest to observe their several risings and the oyl of Vitriol when coagulated sunk more then half an inch below it and being dissolved at the fire returned to its first station as you also saw And this 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 is peculiar to this oyl alone all other liquors rising higher then the mark I now come to my stronger liquors of Beer Ale and Wines I exposed at the same time a flask of small Beer and another of strong Ale the former whereof was frozen throughout in 38. hours but three pints of the Ale continued unfrozen after six days continuance of very hard weather And the air then disposed to thawing I broke the flask and with the unfrozen liquor made an excellent mornings draught at four in the morning This Ale in colour strength and quickness seemed to me and the other three tasters that sate up with me much better then when 't was first put into the flask and by comparing it with some other in the house of the same barrel we plainly found the said difference After this I took the icy part of the Ale and thawed it at a fire which was in all a pint of liquor though the flagon containing three pints of liquor was fill'd with that ice very pale and of a quick and alish taste very much resembling that drink which the brewers call blew John This ice was not so firm as that of water but fuller of bubbles I assayed the same a second time but could not by reason of the changableness of the Weather attain so great a thickness of ice as in the former And in this also I found the same changes as before A beer-glass of Hull Ale in 24. hours contracted a crust of ice as thick as an ½ Crown and proceeding as in Sea-salt water the 〈◊〉 〈◊〉 〈◊〉 〈◊〉 〈◊〉 were the very same all the Laminae taken off appeared of the same colour and taste and the lowest ice was the most tender Another glass of the same Ale exposed did not freez throughout no crust being taken off in five days when my own Ale did in a like glass both being set out together Now the taste and colour appeared the same or at least had no sensible difference when they had been thawed of themselves and when first exposed Hull Ale hath a brackish taste Claret very strong exposed in a spoon in 35. hours hard freezing became an ice all of it it was soft kept its former colour and taste soon discovering to the tongue of one who knew not whence it was its nature quality and kind Canary at the same time in a spoon exposed in 38. hours acquired on its surface an exceeding thin plate of ice as thin as the finest paper and proceeded no farther in four days following Neither Claret nor Canary would shew the least sign of congelation in Tubes much less in Bottles Two ounces of the best spirit of Wine exposed in an earthen pan did all evaporate in less then 12. hours but the same quantity of Brandee left near a spoonful of insipid ice without any taste of the spirit which cast into the fire flamed not at all I could discern no bubbles in this phlegmatick ice but having 〈◊〉 it betwixt mine eye and a candle it manifested many bubbles by its shadows Quaere whether this may not turn to profit in colder Countries in rectifying spirits of Wine We now come to consistent bodies and shall begin with animals and their parts Two eyes the one of an Ox the other of a Sheep in one night were both totally frozen the three humors very hard not separable one from another neither of them Diaphanous as naturally they are and the Chrystalline was as white as that of a whitings boil'd The Tunicles Fat and Muscles were also frozen as appeared by their stifness and by putting them into cold water The ice of the waterish and glassy humors seemed to be made of flakes A pint of Sheeps blood did freez at the top and all the sides of the dish wherein 't was put and was nothing else but the serum of the blood This ice being separated from the blood and thaw'd at the fire and then again exposed congealed into a seeming membranous substance and was taken for such by some that saw it and so continued in a warm season and appeared in all respects a membrane This also was seen and registred in the Journal The blood remaining gave me no signs that frost had taken it I dissected a Dog and a Cat having lain dead in the open air and found their entrails nay the very heart stiff and some little ice in the Ventricles of their hearts and their Vena Cava Milk soon freezeth into most white flakes of ice retaining the proper taste of Milk these flakes are soft and manifest not many bubbles Several Eggs were exposed and both yolk and white in one night were hard frozen They require a longer time to freez then Apples do The best way to thaw them both is to lay them on Newcastle-coal or in a deep Cellar Whether Eggs once frozen will produce Chicken or no I cannot say but have been told by good house-wives they will Some affirm that Eggs and Apples put into water the ice will be thawed within them and the ice appear on the shell and skin 'T is true if you hold either of them near the surface of the water they will soon gather a very thick crust upon their outsides but if you then break the one or cut the other you shall see them full of ice and the Eggs then poched will taste very tough So that this ice seems to be gathered from without and not to come from within And besides if it did so they must needs lose their weight the contrary whereof will anon appear But for the more surety I proceeded to this farther experiment I immersed in my Cistern an Egg and an Apple two foot deep into water and there suspended them with strings tied about them to keep them from sinking for the space of 24. hours and then took them out and opened them I could never observe in that time though I often looked at them any ice on their outsides and the one being broken and the other cut were found both of them full within of ice The next order shall be Vegetables and of them a 〈◊〉 instances 〈◊〉 of those which are of a biting or sowre taste Now for the first I employed the roots of horse-raddish and Onions for other edible roots and plants every one knows will freez which 〈◊〉 the frost had taken them by their taste and ice was found betwixt each of the skins of the Onions 〈◊〉 the taste of the root yet I have observed Beer wherein
Horse-raddish and 〈◊〉 have been infused will not 〈◊〉 so soon as other stronger Beer without them Oranges and Limons frozen have a tough and hard rind their icy juices lose much of their genuine taste they were both frozen hard in 26. hours or a little more having a thick rinde They as other fruits when thawed soon become rotten and therefore the Fruiterers keeps them under ground in low Cellars and cover them with straw as they do their Apples Which did exposed in one night freez throughout If you cut one of them through the middle 't will have on both the plains a most pure thin ice hardly discernable by the eye but easily by the touch or by scraping it off with a knife The cores of these Apples soon turn brown and begin their corruption there Oyl exposed did acquire the consistency of butter melted and cool'd again but in Caves and Cellars I could never see it more then candy Strong White-wine Vinegre did all soon freez in a Tube and without any apparent bubbles And to conclude without mentioning Nuts Bread Butter Cheese Soap and many other things which came under my trial 't is most certain that whatsoever hath any waterish humidity in it is capable of congelation what are not you have in the next Paragraph Having now done with what will freez I shall briefly recount some things whereon the cold hath no such effect We mentioned before spirit of Wine add to it such strong waters as are made of it viz. Aqua Mariae Caelestis c. and Canary Wines in larger vessels Secondly the strong Lees of Soap-boylers and others made of other salts to which refer the spirits extracted from salt Vitriol Salt Petre Aquafortis and spirit of Sulphur which last precipitated to the bottom of the Tube a small quantity of powder very like in colour to Sulphur Vivum which being separated from the spirit for nothing of that evaporated cracked between my teeth and tasted like Brimstone and being put into water made it as white as Lac Sulphuris doth but 't would not flame perhaps because too much of its strong acid spirit was mixed with it Spirit of Soot afforded also a precipitation or sediment the spirit not congealing at the bottom of the Tube of a yellowish colour but much bitterer then the spirit its self and inflamable also But here 't is to be observed that the said spirits that would not freez alone yet with the mixture of about 12. parts of water or less of ice or snow did freez throughout except the spirits of Salt of Nitre and Aqua fortis which would not freez with those quantities of water ice and snow I intended to have tried them with a greater quantity of the said ingredients but the weather failed me Whether the salt water freez in the Sea I cannot experimentally determine but shall add what was told me by one that said he had dissolved ice in the Northern Seas and found it very salt The next proposed was the figure of liquors frozen wherein I shall observe in general that most of the liquors differed one from another in their figures and being permitted to freez and thaw often they still returned to the same figure most whereof were branched Alume appeared in lumps Salt Petre Tartar milk Ale Wine and Sal Armoniac in plates and other liquors mentioned to freez into a very soft ice seeming to be made up of small globuli adhering each to other Fair water kelp and the frits resembled an oaken leaf the leafie parts being taken away and the fibres only remaining the interstitia being fill'd up with smoother ice The middle rib if I may so say as in plants was much bigger then the lateral ones all which seemed but different 〈◊〉 whose points extended towards the outside of the vessel containing the water and made acute angles with the middle rib towards the lesser end of the said leaf Concerning the figures of frozen Urine I shall say nothing the accurate description of curious Mr. Hook having so fully and truly performed that part of my task Now as to the famous experiment of Quercetan and affirmed by many other Chymists I made experiments in these following Vegetables Rosemary Rue Scurvigrass Mints and Plantane wherewith I thus proceeded I mixed with ½ a pint of their distilled waters ½ or ¾ of an ounce of their own salts the Rosemary and Rue were calcined and their salts extracted with their own waters and then were added to their salts their own distill'd waters in the above mentioned proportions The glasses wherein the Rue and Plantane were put being seal'd with Hermes seal and the other glasses left open The effect was that neither of them shewed the least resemblance of the plants from which they were extracted neither figure nor shew of roots stalks branches nor leaves but only a lump or heap of small globuli much less of flour or seed Besides the kelp frozen hath many fibres which is made the most of it of Alga Marina whose leaf is long and smooth without fibres in it This one thing I cannot pretermit that the sented waters seemed upon their thawing to have acquired and advanced much in their sents and especially the Rosemary whose salt hath no smell and its water but little yet thawed they 〈◊〉 as strong almost as fresh leaves rubb'd and smelt too A large recipient was fill'd with water which being frozen throughout and the upper crust of the ice broken there appeared in the middle of it a multitude of thin laminae of ice some more some less wide from which proceeded stiriae or teeth pointing inwards and set at pretty equal distances so that the laminae and stiriae resembled very much so many combs placed in no order some lying directly others obliquely none transversly having intervals betwixt each of them betwixt some of them I could put my finger without breaking the points of the stiriae these combs were placed round about a cavity in the middle of the receiver sufficient to receive two of my fingers In a flask filled competently with water when 't was frozen there appeared throughout the ice infinite silver-coloured bubbles very like unto tailed hail-shot of several sizes the largest about ¼ of an inch long where thickest of the bigness of a great pins-head others much less in all dimensions The points of them all looked outwards and the bigger part inwards towards the Centre where also were the largest For there they would easily admit a little pin into all their cavity without the least resistence The figures of them were pretty regular first a small thread and then a head as big as a shot and thence gradually ended in a point Some of these were straight most a little crooked There was a cavity in the centre of this ice filled with unfrozen water from which I could find multitudes of cavities of bubbles not fully formed And in the more solid parts of the ice cut you may discern them
by a black spot where the hole enters into the cavity All the same Phaenomena appeared in a second trial but that the bubbles were shorter and larger and not so sharp pointed The like I also observed in a Conical glass seal'd up The next thing to be treated of is the effects of freezing viz. the expansion of liquors frozen and consequently thereunto the breaking of bodies wherein they are inclosed All the liquors tried did sensibly in glass Tubes rise beyond my mark before the liquors could sensibly be discerned to freez and after rose somewhat higher with freezing The height of the rising I shall here set of a few experiments instead of many made having troubled your patience too long in the former Paragraphs in several processes Vinegre and Urine rose about half an inch and Lees made with salts of Rosemary kelp the frits about ¼ of an inch Solutions of Alume and Copperas somewhat less and in general the saline liquors less then water which rose a full inch and small Beer in a very narrow Tube four inches but water in the small capillary Tubes could not be perceived either to expand its self and certainly not to freez at all Oyl of Vitriol alone as hath been said sinks below the mark Hot water put into a Tube first sinketh till'tis cold and then riseth before it freez Open-mouth'd glasses such as Beer-glasses c. fill'd with water up to the brim when frozen the ice will manifestly rise above the superficies and make a solid triangle there But narrow necked glasses more plainly shew this rising In a flask filled with water four inches below the mouth the ice rose above the mouth and hung two inches without it And once in a Bolthead the ice rose five inches above the water-mark And here I shall briefly add two things first that if glasses be fill'd about ⅔ full they seldom break but if more they will for the most part break Secondly that round figured or spherical glasses for the most part break in an uniform manner I fill'd a Bolthead full to the neck and stopt it at the top which was 12. inches distant from the body with a piece of melted candle The ice rose above three inches in the neck and the glass brake in the thinnest part of the body from the point of breaking as from a pole the cracks run as so many meridians but unequally distant each from other and consequently concurred not in an opposite pole on the other side besides there was great difference in the length of those cracks none whereof went round the glass In a flask thus crackt in many places the cracks were very irregular in all the places for some of them ran from their centres upwards others downwards some somewhat parallel but most obliquely and few of them were considerably straight Glass-bottles and especially stone Jugs keep very little and the last no method in their breaking the same also 〈◊〉 square glasses woods follow their grain and metals no order at all And now I come to some remarks proceeding as I said from this expansion viz. the breaking of the vessels or force of freezing wherein also you may take notice of that quality of cold mentioned by the Poet penetrabile frigus piercing where light comes not Two Oval Boxes the one of Box the other of Maple both firm woods containing each above two ounces of water were fill'd full and with screws closed very fast both these Boxes were rended from the bottom to the top in one night with gaps big enough to receive a barley corn into them these woods stretch but little and therefore break more surely and with larger rents then softer wood will do Secondly a Pepper Box of Laton made of Iron covered with Tin had the neck broken off and holes made in the top near the neck and the bottom where 't was souldred was so dissevered that water would easily run out there Leaden pipes laid above ground were broken in many places One I saw 20. yards long broken in seven places and another in my Cellar six yards long broken in two places I saw likewise in many places of this City Leaden pipes above a foot deep under ground broken in several parts Cocks of Cisterns and other brass Cocks and also the barrels in pumps made of brass or lead usually break with the frost I exposed a Copper Box of a pear fashion which did bear three several freezings by reason of the great extensibility of that metal but at the fourth assay it crackt all along one side of it almost to the screw Next I tried a Cylindrical silver Inkhorn but that did bear five trials and therein I could perceive neither crack nor dilatation of its superficies I intended to have tried it in a small bottle but the weather fail'd me I exposed also a round silver ball of the bigness of a large Nut the silver became very sensibly extended to a larger superficies but did not suffer any solution of its continuity Tobacco-pipes and all earthen ware taking any frost in their drying before they are burnt become very brittle and being put into a strong fire will certainly break into many pieces Tyles of houses and hard stones in buildings scale and break off upon thawing and thence 't is that the Northern sides of stone-buildings first decay and moulder away as 't is most manifest in ancient magnificent structures Alablaster and Marble having any chinks in them frequently break with frost and the Statuaries tell me they never saw any solid Marble break as for Flints Paving-stones precious stones and such as will receive a polish the bitumens as Amber Kennel-coal c. I could never see any effect on them The next effect shall be that of adhaesion concerning which take the following experiments A smooth piece of ice was laid on a smooth Table and common salt throwed upon it the effect was that the ice stuck so firmly to it that it could not be severed from the table without breaking the ice into many small pieces 't will continue in this close cohaesion till the salt hath corroded through the ice to the very table making many holes in the ice and hath melted it to the very bottom But if you lay salt first upon the table and ice upon it then the ice sticketh not but thaweth These following salts applied as before common salt was cause adhaesion to the table but not so firm as it viz. Kelp Sandever Sal Indus Gem. Prunellae and Armoniac and Pot-ashes but not Alume or Vitriol The next experiment of adhaesion was this I held a nail betwixt my lips in the open air a very little space which stuck so firmly to them that I could not pull it thence without difficulty and pain Another effect is concentration of spirits and colours Concerning the former you have already as much as I know especially in the Paragraph of freezing Beer and Ale Concerning the latter take these following trials
mixtures and that the water riseth higher with then without them I find also that oyl of Vitriol alone mixed with snow or ice have the same effect though not so powerful One affirms that Salt-peter dissolved in water and put into a Bolt-head and long agitated not only cools the hand exceedingly which is very true but also converts it to ice yea in the very Summer month which answereth not my trial though kept a whole hour in that agitation in the hardest season This following Experiment also I add proposed to me I fill'd a Bolt-head containing a quart of water and set it in an Iron pan surrounding it on every side with snow which covered also part of the neck and then set the Kettle over the fire and took now and then the Bolt-head from the fire whilest the snow was thawing but not the least sign of freezing appeared in the water put into the Bolt-head As for the helps of thawing take this Experiment I set in the same Cellar three pans full of ice one on Newcastle coal a second on sand a third on the earthen floor they thawed in the same order they are mentioned which was thrice repeated and once that placed on the coal did thaw when the other continued their ice Seal'd glasses seem neither to promote or hinder this act of freezing The same success I had with Eggs and Apples in my Cellar The last thing I shall speak to is the use of ice you may therewith make a siphon being fashioned and applied as usually siphons are and this will happen whether you make it one continued piece of ice or two contiguous ones for in both the water will run exceeding fast and this siphon soon empties all the water out A second use is for refraction whereof Mr. Hook hath given you already a learned demonstration And I having formed some smooth ice into various figures like most of those mentioned by the Dioptrick writers the 〈◊〉 were the very same as in the like figured glasses but how Des-Cartes made Dioptrick glasses of it I know not especially to make use of them and lastly you may make a speculum of it especially if a piece of blacked paper be placed behind it and if you hold a candle at a convenient distance there will appear very many speculums to your eye according to the number of the bubbles contained in the ice But I could not observe any heat proceed from ice though cut in the true figure for burning-glasses and exposed in naked ice but frozen in spherical glasses 't will heat a little I shall here subjoyn some propositions of learned Bartholinus taken from his book De Nive being near to the former Argument who affirms 1. That the more subtile distilled spirits gain a clear splendor and elegancy from snow placed about them 2. That the rays from snow newly fallen glitter and excel in a kind of splendor wherewith the eyes are dazled Both these are true and have but one common cause vsz the multitude of reflections caused by the infinite globuli whereof every flake of snow consists 3. That he saw Cabbage growing in his garden putrifie on that part which was above the snow 'T is certain that frost alone with or without snow hath this effect on Cabbage being of the tribe of succulent plants and I observed that this year 1644. our great Houseleek or American Aloes usually hung up in houses kept in an upper room was totally destroy'd by the cold And that Apples will 〈◊〉 I have said before and Houswifes to prevent the rotting of Onions commonly hang them up in their Kitchins or keep them in Ovens or some close place And this present year 1662. I saw at Mr. Boxes the eminent Druggists house abundance of Squils or Sea-Onions quite rotten they were laid not in an open but close Garret 4. When snow melts by the Suns heat copious vapours from the Earth cloud the Sun He should rather have said vapours from the melted snow and 't is no wonder that vapours cloud the Sun 5. Snow melts and falls off from Ivy. I have observed all the sorts of Ivies and ever-greens with us and some biting plants too but find in them all the contrary to what is here asserted Nay no difference hath been observed even in hoar frosts which fall equally and continues on all sorts of Plants 6. He excludes not a small portion of earth from snow though pure which saith he is manifest from distillation This experiment I have found true by evaporation which is tantamount to distillation and indeed all melted snow leaves an earthy and foul setling behind it 7. Viscosity with softness is greater in new then in old snow and therefore 't is brought into a mass Viscosity in it I understand not its softness indeed is manifest too by the tracks of beasts which appear more fair the snow not rising on the sides of the impression made by their feet as it doth in old but retains their perfect character 8. Watercresses and Scurvigrass grow under the snow in Gardens I apprehend not that any Plant whatsoever grows at all in hard seasons my meaning is that no Plant acquires any greater bulk of quantity but keeps at a stand only and this Country-men affirm of grass and corn and Gardiners of other Plants 'T is true many Plants will upon thawing shew a finer verdure and if warm weather presently follow all vegetables will thrive exceedingly For how they should thus grow when their nourishing liquor is congeal'd and consequently become immoveable I understand not 9. Air is included in Snow Which this way of mine to make snow fully convinceth I took the whites of Eggs and beat them in the open air with a spoon into a frothy consistence as women do to make their snow possets and then taking a little of this substance and laying it on a trencher it soon became plain flakes of snow so that none that saw them could judge otherwise Another accidental Experiment proves the same for having put water into a Tube and having long and strongly agitated it there arose many bubbles at the top which soon freezing my agitation ceasing became perfect snow And now having here set down the way of counterfeiting at least if not of making snow I will add how a pruina or hoar frost also may be imitated I took a Pail filled with warm water and hung over it Hair Moss and a piece of Rosemary now the atomical vapours rising from the water fixing themselves on the Moss Hair and Rosemary became on them a perfect hoar frost The like is dayly seen on the Beards and Hair of men and horses travelling in cold Winter nights or mornings proceeding from their breaths steams of their bodies or moist atoms of the Air. I tried also to make hail with drops of water but could not hit on 't for they would never become white Whence 't is manifest that hail is not drops of rain suffering glaciation in the
falling as the received opinion of Philosophers asserts 10. Snow abounds with fat This I understand not 11. Snow with ice swims on water This is a clear consequence from the seventh assertion 12. Snow-water boils meat sooner and makes the flesh whiter I tried this in flesh and fish but could find no manifest difference either to their sooner boiling or whiteness 13. Snow newly fallen hath no taste but lying long on the ground or frozen somewhat bites the tongue My taste was not so acute as to distinguish the biting of one from the other T is true indeed that snow frozen doth more affect the tongue with its coldness then snow alone 14. Worms are sometimes found in snow This neither my own observation nor relation from others can make out 15. From snow by a peculiar art a salt of wonderful strength is drawn He saith not this of his own observation nor teacheth the way to extract it 16. After much snow plenty of Nuts This frequently suits with the Country-mans observation but many times fails such years also commonly produce plenty of Wheat other seasons concurring I shall here also insert two remarks out of the same Authors concerning freezing The one is that the great Duke of Tuscany distilled spirit from Wine only by putting snow upon the Alembick without help of fire The second that the Duke of Mantua had a powder which soon congealed water into ice even in the Summer And to conclude take these general observations made by the command of the Royal Society with Weather-glasses fram'd after the Italian mode and fill'd in part with tinged spirit of Wine Which I shall deliver briefly and in gross and not each days alteration apart I took then two of the said glasses of equal dimensions as near as might be and fill'd them with the same spirit of Wine one of them I placed in my Study-window standing North-west the other in Mr. Pulleyns Warehouse under St. Pauls-Church and chose there a small recess or room which was most remote from the entrance and the warmest in the whole Warehouse both the glasses were setled in their stations the 15. of October 1662. the spirit in both having the altitude of three inches just When the glass in my Study was depress'd by the cold an inch I went and observed that in the Warehouse to have received no manifest change in its station And at a second visit the spirit was depressed ¼ of an inch below when that above-ground was depressed near two inches And during the long continuance of all that hard Winter it never descended above ¾ of an inch and never was higher there then three inches and ¼ in a mild season in April following by which time the papers fixed to the glass and whereon were fixed the degrees was quite rotten and the characters scarcely legible And at the same time that in my Study was raised to four inches ¾ By which it appears that the said Warehouse was in the coldest season as warm as in a mild March for at that station the glass in my Study stood commonly betwixt two inches and 2. and ½ And so indeed this place appeared to one that went into it at the coldest season And to this purpose I several times sent in at night my hardest frozen liquors which were constantly thawed in the morning though it freezed exceeding hard above ground The glass in my Study after two days hard freezing was sunk below my marks into the very ball so that I could make no farther observations concerning the cold above ground From the former observations that popular error is manifestly refuted viz. that Cellars and Subterraneous places are hotter in the Winter then in the Summer which though they appear so to us because they warm us in the Winter and cool us in the Summer yet they are not so in themselves for it appears by the former Experiment that in the coldest season the spirit was depressed to two inches and ¼ and rose in April to 3 ½ and no doubt would have risen about ¾ of an inch higher had it continued there till the hottest season of the year One thing more I observed viz. that the tinged spirit of Wine had in this subterraneous Vault totally lost its colour whereas that in my Study two years after still retains its former tincture Since the printing of the foregoing Papers viz. 1664. there being no frosts in England 1663. I made these following Experiments Finding the third of January the season disposed to freezing I exposed a Pint bottle of Claret and a glassCane filled with Canary a solution of Sal Gem Train-oyl and the Oyl of Fructus musae and on the fourth of the same month the night being the coldest and sharpest that I ever felt which all I spake with the next day confirmed the wind then blowing hard at South-west I found in the morning all the liquors frozen except the Sal Gem exposed in an earthen pan which shewed at the bottom of the dish some seemingly Crystallized salt the oyl of the said fruit became very friable and of a milky white colour but the Train-oyl only lost its fluidity and became of the consistence of soft greese And the same night a bottle of the Rhenish Wine called Backrag and another of lusty White-wine standing in a room a story high exposed to the said wind had most of the Wine frozen in them the ices whereof being taken out tasted somewhat weaker then the Wine it self All the same things happened the sixth night of the same month It is to be observed that the pint of Claret and the Sack in the tube were both frozen throughout these two nights and after their double freezing and thawing they lost nothing of their spirit colour and taste nay the Claret being a strong Burgundy Wine though it often suffered glaciation and thawing for three weeks together yet in all that time suffered no manifest alteration but appeared the same to sence as when it was exposed in colour taste and strength As to the concentration of coloured liquors Mr. Haak shewed me an Oval glass having at one end a narrow Cane above an inch long almost filled with water tinged with Cochineel frozen throughout the ice round about towards the sides of the glass shewed wholly colourless but that in the midst was of an exceeding high dye but the ice that was raised to the neck of the glass was lightly tinged with a scarlet hue Hereupon having some flasks by me I put into one a strong decoction of Cochineel and into another a like decoction of Soot which being exposed to the air and incompassed in a vessel with snow and salt they did freez to the thickness of an inch or more and the air then beginning to relax I broke the flasks and the desolved ice yielded a water totally colourless I made also an Experiment with a very strong decoction of Gentian roots which being exposed in a four ounce vial the ice thereof had
a true 〈◊〉 or a coagulated substance that look'd just like Ice both 〈◊〉 eminent Virtuosi and I my self who had the Curiosity to 〈◊〉 it can bear him witness Lib. 1. Titulo de frig Asperitate pag. 9. This is pointed at in the third Page of the following Account where mention is made of an Honorable Person c. See the Publisher's Advertisement to the Reader * Among which I am since informed that he had tried divers before he saw my Papers * So one of the chief Passages of the Examen of Antiperistasis is much confirmed by the Forty Fourth and Forty Fifth Pages of the following Papers which contain an Account of a Trial made by the command of the Royal Society to whom it was proposed by the Author of the Examen with a request that they would be pleased to order it to be made The Art of Pottery Pag. 27 28. See the 18. of our New Physico-Mechanical Experiments In the defence against Linus Cap. 4 Dr. H. P. An Ingenious man has proposed another way of setling a Standard for Weather-glasses namely by observing the coldness which is requisite to make distill'd water begin to freez But though the accurateness of this way may be as well as the other justly Question'd and cannot often be put in practise even in Winter it self nor without trouble yet it may also be advantagiously made use of when the cold happens to be great enough to freez water Dr. Wren Dr. Goddard Mr. Hook Defence against Linus Cap. the 5th Theatr. Chynic volum 6. Vitrum optimè clausum ne quid exspir are posset in loco ubi quiesceret statui 〈◊〉 sine animi voluptate lice bat in Pleniluniis manifesta inclusi liquoris incrementa observare in Noviluniis vero Decrementa c. They are the words of Paulus Casatus in his Terra Machinis mota Pag. 143. But since the writing of these Praeliminary Discourses the Author of them having consulted by the means of some Ingenious friends the learned Casatus finds that He never made nor saw the Experiment himself but relates it upon the authority of a certain Dutchman whose name he adds not and who therefore may probably be the same Orthelius that is mention'd by the Author of these Praeliminary Discourses who thinks it requisite to give the Reader this Advertisement because Casatus himself did not as he should have done intimate that he de iver'd this but upon anothers credit L' Hydrographie du P. Fournier liv 18. Cap. 12. Defence against Linus Cap. 3. Sect. 11. of the same 30. Chap. See more concerning these Weather-glasses in the first of these three Discourses See th 〈…〉 gure 〈…〉 rest 〈…〉 Pag. 58. Olai Magni Gent. Sept. Hist. Lib. 11. Cap. 24. Olaus Magnus in Historia Gentium Septentrionalium lib. 11. cap. 20. 21. Cap. 6. pag. 42. See the Praeliminary Discourses 4. Jan. 15. * See the latter part of the next Title In the Discourse touching the primum frigidum Gulielmus Fabritius Hildanus de Gangr 〈◊〉 Cap. 10. Barthol de usu Nivis pag. 80. Pag. 74. Pag. 79. Barthol de figurâ nivis pag. 79 〈◊〉 de usu Nivis pag. 83. Capt. James's Trav. pag. 76. Barthol de usu Nivis Cap. 12. * Of the usefulness of Experimental Philosophy Purch Lib. 3. cap. 5. Sect. 2. pag. 493. Pag. 73. Pag. 67. Lib. 1. Sect. 〈◊〉 Cap. 5. pag. 122. Nicholaus Zucchius Melchior Cornaeus It froze so sore within the house that the Walls the Roof thereof were frozen two fingers thick with Ice and also in our Cabins where we lay all those three days while we could not go out Gerat de 〈◊〉 in his third Voyage Pag. 64. Feb. 4. 1661. Decemb. 11. 1662. Decemb. Decemb. Decemb. the 17. Barthol de Nivis usu Chap. 6. * In our Hydrostatical Paradoxes Ex nive copiosa glaciata compacta Pag. 14. * Mr. Hudsons Voyage for the discovery of the North-west passage written partly by Mr. Abacuck Pricket * In the Sect about the Temperature of the Air. * New Exp. Physico-mech Exper. 6. †See the forecited place * The Appendix to the Physico-mechanical Experiments Decemb. the 13. Decemb. 13. Voyage de 〈◊〉 de Perse Liv. V. Pag. 63. Pag. 86. * The breadth was I know not how omitted in the note but as I remember it was about an 8. part of an Inch. Olaus Ma. Gent. Septentr Hist. Lib. 1. Cap. 14. Purchas Lib. 4. Cap. 13. Purchas lib. 4. cap. 13. pag. 813. * Neither hereafter will I marvel though the strait of Weigats be stopped up to the Northeast with such huge mountains of Ice since the Rivers Oby and Jenesce and very many more whose names are not yet known pour out such a quantity thereof that in a manner it is incredible For it cometh to pass in the beginning of the Spring that in places near unto the Sea the Ice through the excessive thickness and multitude thereof doth carry down wood before it And without doubt this is the cause that about the shore of the strait of Weigates so great abundance of floatiug wood is every where seen and whereas in that strait near nnto Nova Zembla it is so extreme Cold it is no marvel if in regard of the narrowness of the strait so huge heaps of Ice are gathered and frozen together that in the end they grow to sixty or at least to fifty fathomes thickness Says the Description of the Countreys of Siberia Samojeda c. extant in Purchas's third part of his Pilgrim Lib. 3. Cap. 7. Pag. 14. Pag. 106. Purchas lib. 4. cap. 18. pag. 837. Pag. 17. Hydrographie du P. G. Fournier liv 9. cap. 29. compar'd with the 22. Chap. of the same Book Olai Mag. lib. 3. cap. 2. pag. 334 * Saepe aliàs his annis fatalibus tam profundè congelavit marina Aqua ut non tantùm plaustra sed integrum exercitum ad aliquot Milliaria Germanica secure vexerit c. Inquit T. Barthol De nivis usu pag. 43. Barthol de nivis usu cap. 6. Glycas apud Fournier liv 9. cap. 19. In the Evening we were inclosed amongst great pieces of Ice as high as our Poop and some of the sharp blew corners of them did reach quite under us Capt. Jam. pag. 6. Olaus lib. 1. cap. 14. Olaus Magnus 〈◊〉 11. Blefkenius in Purch lib. 3. cap. 22. I have seen also the sides lin'd with reeds 〈◊〉 instead of boarding or steening Pag. 101. Pag. 〈◊〉 * In the Sceptical Chymist The Dialogues about heat and flame 〈◊〉 Bernard de Palissey au Traitté du Sel commum De Claves au second Livre das pierres pierreris Cap. 2. Ibid. 〈◊〉 de 〈◊〉 livre 11. cap. 2. * In the Discourses about Antiperistasis the following passages are taken out of a 〈◊〉 narrative consisting of about two sheets of paper of Joh. Baptista Morinus published in the year 1619. and titled Relatio de locis Subterraneis annexed
themselves again and fly about amazedly for a while but not long survive so great and sudden a change I have in another Treatise already said somewhat about this Tradition and therefore shall now say no more of it then these two things First that I since was assur'd by a person of honour that is very curious and was commanded by a many ways great Prince to inquire out the truth of it when he was in some of those Countries where the thing is said to be familiar enough and that the 〈◊〉 and soberest persons he could ask affirm'd the thing to be true But secondly having lately inquired about this matter of a knowing person of quality that was born and bred in Poland he answered me That in the parts where he liv'd it was a very general and unquestion'd opinion that Swallows often hid themselves all the Winter under water in Ponds and Lakes and Seggy places and that the Fishermen when having broken the ice they cast their Nets for Fish do draw them up benummed but not dead so that they quickly in Stoves recover their wings but seldom after that prolong their lives But as for their being taken up in ice he told me he had not heard of it though I see not why in case they commit themselves to shallow waters as those of Ponds and Seggy places often are a sharp lasting frost may not sometimes reach them And therefore that which left me the greatest scruple about this Tradition is That this Gentleman notwithstanding his curiosity could not affirm that ever he himself had seen any example of the thing he related But I will take this occasion to add that having a mind in frosty weather to try some Anatomical Experiments about Frogs one that I imploy'd breaking in a Ditch some ice that was very thick and of which he was to bring me a quantity found in the water that was under the ice good store of Frogs besides some Toads which I found to be very lively and divers of which I kept for certain uses a good while after To confirm and to add some Paralipomena unto what I have deliver'd in the Second and in the Twentieth Titles about the frosts getting into hard and solid bodies I shall here subjoyn some particulars there omitted which I have learned partly from Experiments and partly from persons worthy of credit whom I purposely consulted about this matter And first as to the freezing of Wood we have sometimes tri'd it by purposely exposing partly other Wood and partly branches cut off from growing Trees to an intense degree of Cold by which the wood seem'd in one night to be for some little depth manifestly enough invaded by the frost But a domestick of mine having a little while since had occasion to fell an old Apple-tree on a day that had been preceded by a fortnights bitter frost came and informed me That he found that the frost had evidently pierc'd into the very middle of it though it were about a foot in Diameter And an Experienc'd Artificer whose head and hand were much imploy'd about the building of great mens houses told me that he had often seen here in England pieces of Timber it self manifestly frozen and rendred exceeding difficult to be saw'd the frost also appearing by evident signs to continue in the saw-dust And therefore it will be the less strange if in Poland the effects of Cold upon wood be more conspicuous For a learned native assur'd me that in his Countrey 't was usual to have wood frozen so hard that the Hatchets would not cut it but rebound from it and that 't was very usual to hear in the night a great many loud cracks almost like the reports of Pistols of the shingles or wooden tyles wherewith in many places they cover their houses instead of Slate and this as I purposely ask'd when the weather was dry and excessively cold When I likewise inquir'd about the thawing of wood he told me he had several times seen pieces of Timber which having been throughly frozen in the Air did when brought into rooms made warm by Stoves become cover'd with a kind of hoar frost and made them look white and that though his Bow which he shew'd me were very strong and tough as being made not of wood but horn and other close materials it would be so chang'd by the frost that unless special care were had in the thawing of it it would break That Marle and Chalk and other less solid terrestrial Concretions will be shatter'd by strong and durable frosts is observ'd by Husbandmen who thereby find it the better fitted to manure their land the Texture of those bodies during whose intireness the parts most proper to feed grass and corn are more lock'd up being by congelation in great part dissolv'd but that true and solid stones wont to be imploy'd in noble and durable Buildings should be spoil'd by the frost will perhaps to most readers seem very improbable And therefore I shall here add what I have learn'd by inquiry of the ingeniousest and most experienc'd Mason I have met with because it may not only surprize most readers but prove an useful observation to him Having then inquir'd of this Tradesman whether he did not find that some free stone a name vulgarly known would not be spoil'd by the frost he told me that he had often observ'd both free stone and harder stones then that to be exceedingly spoil'd by the frost and reduc'd to crack or scale off to the blemishing and prejudice of the houses that are built of them But because it may be objected against this that experience shews us that divers of the stateliest Fabricks in England have these stones for their chief materials and yet indure very well the inclemencies of the Air the reply may be that the difference may not consist in the peculiar natures of the stones imploy'd but in the several seasons in which the same kind of stones are digg'd out of the Quarry For if they be digg'd up when the cold weather is already come in and imploy'd in building the same Winter they will upon very hard frosts be apt to be shatter'd or scale but if they be digg'd early in the Summer and suffer'd to lye expos'd to the Sun and Air during all the heat of the Summer these season'd stones if I may so call them may outlast many sharp Winters unimpair'd It seems to me worth trying whether during their insolation if that term may be allow'd me there do not by the operation of the heat and air upon them exhale a certain unripe mineral sap or moisture whose recess may perhaps be discover'd by weight which if it remain in the stone may by very piercing frosts be congeal'd almost like the sap in Timber-trees and shatter the Texture of the stone which agrees well with what was told me by an understanding person that is Master of a great Glass-house of whom having purposely inquir'd whether he did
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