Bodies whereby I have reduc'd sometimes one sometimes another of them together with the Menstruum which needs not much exceed them in Bulk to the consistence of a fluid Body We see likewise that Fusion makes metalls fluid and in Fusion there is manifestly a comminution of the melted Body the Heat alone of Gold Silver or Iron though encreas'd even to Ignition being not able to make those metalls become fluid whilst they continue in masses of any sensible bulk To which I shall adde anon that even melted Metalls may have their Fluidity encreas'd by a yet further Comminution of their parts SECT VII And to resume here the Consideration of that very difficult Question which we have elsewhere menâ—ion'd it seems well worth Enquiry whence it happens that in the distillation of common Salt and other saline Bodies which not only are not fluid but are hard ev'n to brittleness there will yet be obtain'd a perfect and permanent Liquor and from some of them a very considerable proportion of it In answer to this Question it may indeed be said That in diverse dry Bodies such as Harts-horn Wood and Bones committed to distillation the fire does no more than separate the aqueous or other liquid parts from the others wherewith they were blended in the Concrete and bring them together into the Receiver where they convene into a Liquor But besides that this it self is perhaps more easily said than prov'd it does not reach the propounded Difficulty For with what probability can it be affirm'd of Bodies that have been already calcin'd or melted such as are the red Calx of Vitriol and flux'd Sea Salt c. which yet afford Liquors though their aqueous and other looser parts have been already driven away by a strong fire before their being expos'd to distillation I have sometimes then consider'd whether it may not seem less improbable to conjecture that the vehement agitation produc'd in such Bodies by the violence of Heat does both divide them into minute Corpuscles and drive over swarms of them into the cold Receiver where loosing their former vehemence of agitation they are reduc'd into a Liquor chiefly for I would not exclude concurrent causes by reason that the fire happen'd to rend the Concrete into parts by their extreme littleness or their shape or both so easie to be tumbled up and down that the wonted agitation of the Air propagated by the interpos'd Bodies or Medium or else that the same cause whatever it be that gives the Air its wonted agitation is able to give such minute Corpuscles enough of it to keep them fluid SECT VIII That there is constantly in the Air a various motion of the small parts will be anon declared That also some Bodies will be kept fluid by a much less measure of agitation than is requisite to others seems probable from hence That Wine will continue a Liquor in such a languid warmth of the Air as will not keep the parts of water moving but permit them to rest in the form of Ice And in cold Countries where Wine it self would congeal as I have by Art made it do here in England 't is observ'd that though the more aqueous parts will by the loss of their motion be turn'd into Ice yet the more subtil and spirituous parts remain unfrozen and so do diverse other Liquors especially Chymical of very subtil and voluble parts And the Corpuscles that chiefly compose that Body which is properly call'd the Air though it appears by weather-glasses that Cold may very much contribute to condense it that is to occasion the approach of its parts to one another or reduce them to a closer order have not been observ'd to be frozen by any degree of cold whatsoever which seems to proceed from hence that by reason of their extream littleness not excluding their figure there cannot be so little of agitation about the Earth as not to be sufficient â—o continue a various motion in such very minute Bodies and consequently to keep them fluid Now That likewise it is possible that a saline Spirit should consist at least in great part of very minute grains of Salt we elsewhere declare where 't is taught that a Sal-Armoniack may be made by Spirit of Urine and Spirit of Salt as the common Sal-Armoniack is made with crude Salt and there a way is also shewn how these two Salts the Urinous and the other as strictly as they are united in the compound may be readily divorc'd And agreeably to this I observe that as according to what I elsewhere note a common Aqua fortis may be enabl'd to dissolve Gold on which of it self it will not fasten by the addition of Spirit of Salt so I find that common crude Salt barely dissolv'd in it will give it the like power of working upon Gold Nay I have try'd that crude Nitre dissolv'd in good Spirit of Salt may make it serve for an Aqua Regis And I remember on this occasion that having enquir'd of the most noted Person in Holland for the distilling of corrosive waters what was the greatest proportion of distill'd Liquors that ever he was able to obtain from Sea Salt he though a man not given so much as to boasting affirmed to me that by using instead of the ordinary Caput mortuum as Brick-dust Sand c. that Chymists are wont to mingle with Salt before they distil it a certain whitish clay he had sometimes brought over almost the whole body of Salt into a Liquor insomuch that from a pound of Salt he could draw and that without any extraordinary trouble or degree of fire fourteen Ounces of Liquor And when because I suspected that much of this might be water forc'd from the clay mingled with the Salt I enquired whether he had ever dephlegmed this Liquor He answered me that he had purposely done it and sometimes found no less than about twelve ounces of it to be strong rectify'd Spirit which brought into my mind that almost incredible passage of Beguinus who somewhere teaching the Distillation of another Salt addes to the end of his Directions That if you have wrought well you shall get from a pound of the matter a pound of Spirit But because from all these Liquors distill'd from such kind of Salts 't is possible either by Rectification or some more Philosophical way to obtain a portion of phlegm or water I leave it to further Enquiry whether or no the Fluidity of these distill'd Liquors may not in diverse cases be in part further'd by the mixture of some particleâ— of an aqueous nature such being fit to make Dissolvers and vehicles for Salts which may not absurdly be suspected to have been produc'd by the action of the fire upon the Concrete committed to distillation if we allow with that famous Chymist Helmont That by the Alchahest all gross Bodies may be totally and that without it ev'n Oyle and Salt may in great part and that without Additaments be reduc'd into insipid water SECT IX We shall anon when we come to treat of Firmness mention our having made a certain substance so dispos'd to Fluidity that it may be made to change the stable consistence for a liquid one by so small an Agitation as only the Surplusage of that which the ambient Air is wont to have about the middle even of a Winters day above what it hath in the first or latter part of
especially if they be such whose preciousness may make their Sophistication very beneficial to them that practise it It has been lately much complained of by some of the Cultivators of Clover-grass that of a great quanâ—ity of the Seed not any Grass sprung up which not being imputable to the Soyl nor the Sower proceeds as some Analogical observations make me suppose from the effeteness if I may so speak of the superannuated Seed sometimes sold in the Shops And upon this Subject I cannot conceal from you what was lately affirm'd to me by one of the eminentest and soberest Chymists of Amsterdam who was also an Indian Merchant who assur'd me that most of the Cinnamon and Cloves that is brought into these Western Regions is defrauded in the Indies of much of the finest and subtilest Aromatical parts before it be sent into Europe And to give a more familiar Instance to our present purpose you may be pleased to remember Pyrophilus that in one of the first of these Essays we have made mention to you of great store of living Creatures which we had observed in Vinegar of the truth of which Observation we can produce divers learned and severe Witnesses who were not to be convinced of it till we had fully satisfi'd them by ocular demonstration and yet Pyrophilus there are divers parcels of excellent Vinegar wherein you may in vain seek for these living Creatures and we are now distilling some of that Liquor which if we did not think to be of the strongest and best sort we should scarce think worth the being distill'd for Spirit wherein nevertheless we can neither by Candle-light nor by day-light discern Any of those liâ—tle Creatures of which we have often seen Swarms in other Vinegars Of such fraudulent tricks as those lately mention'd I could easily give you divers Instances if I were not afraid of teaching Fallacies by discovering them But some are so notorious or otherwise of such a nature as that it may be more useful than dangerous to mention them It is commonly known that Sublimate is wont to be sophisticated with Arsnick and how differing the effects of such Sublimate may be from those of that which is faithfully prepar'd not only upon Metalâ— but when Mercurius Dulcis and other Preparations are made of it upon humane Bodies they and scarce any but they who are acquainted wiâ—h the noxious qualities of Arsnick both to Metals and Men can readily imagine And indeed as for Chymical Preparations Helmont was not much in the wrong when he affirm'd There were scarce any vulgarly sold in shops to be rely'd on as faithfully prepar'd And for my part I have so often met with Chymical Preparations which I have found unsincere that I dare scarce trust any either in the administration of Physick or so much as in the tryal of considerable Expeâ—iments which either my own Furnaces do not afford me or wherewith I am not supply'd by some person of whose skill and faithfulness I have a good opinion The other day having occasion to use some Spirit of Salt whereof I was not then provided I sent for some to a Chymist who making it himself was the likelier to afford that which was wall made but though I gave him his own rate for it at the first Rectification even in a Retort a single pound afforded us no less than six ounces of phlegm and afterwards being further rectifi'd in a high body and gentle heat the remaining Spirit parted with a scarce credible quantity of the like nauseous liquor and after all these sequestrations of phlegm was not pure enough to peâ—form what we expected from it Of which complaining to an excellent Chymist of my acquaintance he sent for â—pirit of Salt to a very eminent Distiller of it who gets much by his profession and passeth for a very honest man but this Spirit besides its weakness discover'd it self to be sophisâ—icated with either Spirit of Nitre or Aqua fortis which betray'd it self by its peculiar and odious smell whereas Spirit of Salt skilfully and sincerely drawn is commonly of a greenish colour bordering upon yellow and hath usually a Peculiar and sometimes as I can exemplifie to you in some of mine a not Unpleasing smell And let me on this occasion advertise you Pyrophilus that in divers cases 't is not enough to separate the aqueous parts by Dephlegmation as many Chymists content themselves to do but some Liquors contain also an unsuspected quantity of small corpuscules of somewhat an earthy nature which being associated with the saline ones do clog or blunt them and thereby weaken their activity And therefore such Liquors to be well depurated require the being distill'd off and that with a slow fire that the dry faeces may be left behind in the bottom of the Glass To satisfie some persons that this Observation is not groundless we have sometimes taken of the better sort of Spirit of Salt and having carefully dephlegm'd it remov'd it into lower Glasses that the less heat will suffice to make the Liquor ascend and having gently abstracted the whole Spirit there remain'd in the bottom and the neck of the Retort whence 't was distill'd so great a quantity of a certain dry and stiptical substance for the most part of a yellowish colour that it seem'd strange to the beholders that so clear a Spirit should conceal so much of it and we our selves should have wonder'd at it too had we not remember'd that in what the Chymists are wont to call the Oyl or Rectifi'd Butter of Antimony made with Sublimate the Liquor though distill'd and very limpid almost like fair water consists in great part of the very body of the Antimony which we would here manifest but that we elsewhere do it and therefore chuse rather in this place to take notice that the Spirit of Salt after this second depuration was so chang'd that it seem'd to be a much nobler and almost another Liquor than it was before But to return to our sophisticated Spirit what differing effects would be produc'd by true Spirit of Salt and that which is mixt with the Spirit of Nitre he that knows the great disparity in the operations of those two Liquors whereof to mention now no other Instances the former will precipitate Silver when the latter has dissolv'd it may easily inform you Which Instances I mention not as the considerablest which may be produc'd on this Subject but as the freshest in my memory In the next place Pyrophilus I observe that even when the Materials imploy'd about Experiments are no way sophisticated but genuine and such as Nature has produc'd them or Art ought to prepare them even then I say there may be a very considerable Disparity betwixt Concretions of the same kind and name and which pass without suspicion for bodies of perfectly the same nature This may to you Pyrophilus seem a great Paradox but perhaps upon examination it will appear a great Truth which because I am
glass Pipe of an indifferent size and open at both ends and if when 't is well fill'd with smoak the lower end be presently stopt and the glass be kept still a while in an erected posture the fumes will settle by degrees to a level superficies like water so that though you gently incline the Pipe any way the upper surface of the smoak will neverthelesse quickly grow parallel to the Horizon And if the glasse be further but slowly made to stoop the smoak will seem to run down in a Body like water whilst it continues in the Pipe though when it is come to the lower end of it instead of dropping down like water it will commonly rather flye upwards and disperse it self into the Aire And as for flame I fore-see I shall ere long have occasion to mention an Experiment whereby I have sometimes endeavour'd to shew that ev'n two contiguous flames as expanded Bodies as they are and as open as their Texture is may like visible Fluids of a differing kind retain distinct surfaces SECT V. But instead of Examining any further how many Bodies are or may be made visibly to appear fluid ones let us now resume the Consideration of what it is that make Bodies fluid especially since having intimated some of the Reasons why we are unwilling to Confine our selves to the Epicurean notion we hope it will the lesse be dislik'd that we thought fit to make such a description of a fluid substance as may intimate that we conceive the conditions of it to be Chiefly these Three The first is the Littlenesse of the Bodies that compose it For in big parcels of matter besides the greater inequalities or roughnesses that are usual upon their surfaces and may hinder the easie sliding of those Bodies along one another and besides that diverse other Affections of a fluid Body cannot well belong to an aggregate of grosse Lumps of matter besides these things I say the bulk it self is apt to make them so heavy that they cannot be agitated by the power of those causes whatever they be that make the minute parts of fluid Bodies move so freely up and down among themselves whereas it would scarce be believ'd how much the smallnesse of parts may facilitate their being easily put into motion and kept in it if we were not able to confirme it by Chymical Experiments But we see that Lead Qâ—ick-silver and ev'n Gold it self though whilst they are of a sensible bulk they will readily sink to the bottom of Aqua Regis or any other such Liquor yet when the Menstruum has corroded them or fretted them asunder into very minute parts those minute Corpuscles grow then so much more capable of agitation than before that quitting the bottom of the Liquor they are carri'd freely every way and to the top with the associated parts of the Liquor without falling back again to the bottom Nay we see that ponderous and mineral Bodies divided into corpuscles small enough may be made so light and voluble as to become Ingredients ev'n of distill'd Liquors as we may learn by what some Chymists call the Butter others simply the Oyle and others the Oleum Glaciale of Antimony which though it be after Rectification a very limpid Liquor yet does in great part consist of the very Body of the Antimony as may appear not to mention its weight by this that 't is most easie to precipitate out of it with fair water store of a ponderous white calx reducible by Art to an Antimonial glasse Nay we make a Menstruum with which we can easily at the first or second Distillation bring over Gold enough to make the distill'd Liquor appear and continue ennobled with a Golden Colour And to show yet more particularly that great Bodies are too unwieldy to constitute fluid ones We may further observe how as well Nature as Art when either of them makes Bodies of considerable bulk fluid is wont in order thereunto to make a Comminution of them as we may observe in divers Examples SECT VI. Thus we see that in the stomacks of Dogs Nature to reduce Bones into those fluid Bodies Chyle and Blood does by some powerful and appropriated juice whether belonging to the Stomack it self or thrown out of the Arteries in the passage of the circulating Blood dissolve them into parts so minute that the acutest Eye would not tempt a man to suspect that such a Liquor had ever been a Bone And that it may not be objected that this dissolution is chiefly performed or at least must always be assisted by the Liquor which Animals take into their Stomachs by drinking I shall represent not only that we find by experience how little common water the only usual drink of Dogs Wolves c. is able to dissolve bones though they be very long not macerated but boil'd in it but that if we may believe Natural Historians and credible Travellers there are some sorts of Animals as particularly Camels that may be brought not to drink once in many days ev'n when they travel in hot Climates And to make you think this the less improbable I shall adde that I am familiarly acquainted with an Ingenious Gentleman who as himself and an ancient Virtuoso in whose house he lives have inform'd me does usually drink but once in several days and then no excessive draught neither And when I askt him how long he had actually abstain'd not barely from drink but from thirsting after it He answer'd that he had once some few years before continued about nine days without either taking or needing any drink and he doubted not but that he might have continued much longer in that state if by distempering himself one night with long and hard study he had not had some light inclination to take a small draught which serv'd him for about four days longer And when I askt him whether in that hot Summers day that preceded the evening wherein he happen'd to tell me this he had not drunk at all he answer'd Negatively And it adds to the strangeness of this Peculiarity that this Gentleman is in the flower of his Youth being but about twenty two years of Age and of a Sanguine and Florid Complexion And to annex that also upon the By I learned by enquiry from him that he sweats freely enough as I remember I saw him do that his Diet is the same with other mens without restraining him from the free use of Salt Meats and that his Urine is in Quantity much like that of ordinary Men of his Age and temperament But to return to what I was saying more generally of the Stomachical Menstruum of Animals I shall adde on this occasion that to make some kind of Imitation of it I prepar'd and do elsewhere mention and teach a certain Liquor that I use whereby I have in a short time and without fire dissociated the parts of rosted or boil'd flesh bread fruit c. and pull'd them asunder into very minute
this That if you take Salt of Tartar first brought to fusion and place it in a Cellar or ev'n in an ordinary Room it will in a short time now and then in a few minutes begin to relent and have its surface softn'd by the imbib'd moisture of the air wherein if it be left long enough it will totally be dissolved into clear Liquor which would not be if the moist vapours that help to constitute the air did not move to and fro every way and were not thereby brought to the Salt and enabled to insinuate themselves into its pores and by that means dissolve it and reduce it with themselves into a Liquor And even in Summer when the air is wont to be much dryer than at other Seasons of the year one may quickly discover that there are in the air store of aqueous Corpuscles mov'd some one way and some another by the Experiment of putting into a Drinking-glass for want of Ice and Snow some Beer or Wine actually very cold for thereby after a while the outside will appear all bedew'd with little drops of Liquor which seems plainly to be no other than the aqueous steams that swimming up and down in great multitudes in the air are by its agitation towards all parts carried as every other way so to the sides of the Glass and being there condens'd by the coldness of that smooth Body turn into visible and palpable water And if I much mis-remember not it was one of the circumstances of the last Experiment of this kind we have had occasion to take notice of That the drops that fastn'd themselves to the outside of the Glass purposely left in part unfill'd reach'd either not at all or very little further than the surface of the Liquor within the Glass whose coldness as it seems did not infrigidate those upper parts of the Glass to whose level the Liquor it self did not reach To which I could easily adde Arguments to prove that the drops we have been speaking of proceeded not from the transudation of the Liquor within the Glass if I thought it worth while to disprove so unlikely a Conjecture But instead of that I shall only intimate that from this Experiment useful hints may be taken both Theorical and Practical and particularly that a Reason may perchance be given of a strange way of catching a Salt and Liquor out of air barely by glass-vessels of a peculiar and skilful contrivance Much of what we have lately said will I presume be the less wonder'd at if we subjoyn what Experience has taught us That 't is not difficult by the help of a convenient Furnace and fit Vessels to make that ponderous Metal Lead ascend to a good height in the open air in the form of a copious smoak such a smoak we discern'd after a while to be carried so many ways by the aerial Corpuscles that it met with in actual motion that it was soon dispers'd so far as to disappear which perhaps will be thought some confirmation of what we formerly deliver'd when we taught how much the being divided into very minute parts may conduce to the Fluidity even of ponderous Bodies SECT XXII And though Quick-silver be excepting Gold the heaviest known body in the world yet when it is reduc'd into vapour it seems to be carried to and fro like the other terrestrial particles that swim up and down in our air for I remember that an expert Gilder not long since complain'd to me that if when he evaporated Quick-silver he forgot to take off his Rings from his hand though they touch'd not the Quick-silver whilst it was in a body the roving fumes would oftentimes fasten upon the Gold in such plenty as would put him to much trouble to get them off from his Rings one of which he shew'd me that he had lately thus whitened and as it were silver'd over with Mercurial fumes and was then to restore to its native Yellow SECT XXIII But let us return to visible Liquors and endeavour to prove almost ad Oculum as they speak that their insâ—nsible parts may be every way agitated though their motion be but seldom visible to us Take then what quantity you please of Aqua fortis and dissolve in it as much as you please of ordinary coyn'd Silver it not being necessary for this Experiment that it be refin'd and pour the coloured solution into 12 or 15 times as much fair water and then decant or filtrate the mixture that it may be very clear If you look upon this Liquor the parts of it will seem to be all of them as perfectly at rest as those of common water nor will your Eye be able to distinguish any Corpuscles of Silver swimming in the Liquor and yet that there are such metalline Corpuscles agitated to and fro with and by those of the water will quickly appear if you immerse into it a flatted piece of clean Copper for by that time you have held it two or three minutes of an hour perhaps not so long in the Liquor you shall see the particles of Silver that were roving up and down the Liquor fasten themselves in such swarms to the Copper-plate that they will appear in their native hue and cover it as it were with a loose case of Silver which may be easily shaken off in the form of a metalline powder and if several such Plates be left all night or for a competent number of hours in the bottom of the Vessel you may the next day find all the particles of Silver that were dispers'd through the whole body of the Liquor setled upon or about them the deep blewish green tincture you will discover in the water proceeding only from some little parts of the Copper-plates and of the Alloy of the Coyn dissolv'd by the saline particles of the Aqua fortis And I remember that to compleat the Experiment I have sometimes made even these fall to the bottom of the Vessel by leaving a lump or two of Spelter there for two or three days for not only those metalline Corpuscles that were just over or near to the determinate place where I put the Spelter but also all the rest into how remote parts soever of the Liquor they were diffus'd did setle upon the Spelter as appear'd both by its increase of bulk and by their leaving the water clear and colourless which plainly seems to have proceeded from hence that the particles of the water were restlesly and every way agitated and so by frequently gliding along the surface of the Spelter they must carry thither of the Corpuscles of Copper mingled with them some at one time and some at another till at length all were brought to it and detain'd there SECT XXIV That of the particles of Spirit of Wine and such like inflammable Liquors drawn from fermented Juyces though they seem to the Eye to be at rest a good many do yet move confusedly and very nimbly I remember I have long since
already make up much the greater part of the Universe especially since I could easily enough make it probable that such steams of the terrestrial Globe as may well be suppos'd to be the chief Ingredients of our Atmosphere may like a Liquor retain a superficies distinct from that of the ambient and contiguous Body And since we are speaking of the distinct surface of fluids the occasion invites me to add an Experiment which though apt to miscarry upon the account of unheeded Circumstances has yet when all things were rightly order'd succeeded very well I will I say subjoin it here because it shews a way of dividing in a trice a Liquor Transparent and as to sense Homogeneous into two very differing Liquors the one Diaphanous and the other Opacous which will not mingle The Experiment is this Dissolve one Ounce of clean common Quick-silver in about two Ounces of pure Aqua fortis so that the Solution be clear and total then whilst it is yet warm pour into it by degrees lest they boyl over half an Ounce or one Ounce of Filings of Lead and if no Error nor ill Accident have interven'd the Lead will be in a trice praecipitated into a white Powder and the Mercury reduc'd into a Mass if I may so speak of running Quick-silver over which the remaining part of the Aqua fortis will swim whereby we may see that Liquors being reduc'd into very minute parts may mingle very well the Corpuscles of the one supporting in that state those of the other though in greater Bulk especially the Texture of one being somewhat varied they will retain distinct Surfaces N.B. Note that when the Operation succeeds not well the Mercury need not for all that be lost but may in great part at least be recover'd by freeing the Praecipitated matter from the rest by filtration and then diligently grinding the white Praecipitate with Water by which means the Mercury will little by little be gaâ—hered into drops And though this be far from being the true Mercury of Lead as I may elsewhere shew you yet some Inducements not here to be named incline me to look upon it as somewhat differing from common Mercury and fitter than it for certain Chymical uses SECT XXVII And here I should pass on to the Consideration of Firmness but that when a while ago I discours'd of the Agitation of the Corpuscles that compose Oyl of Tartar and Oyl of Vitriol I forgot to add that not only in fluid bodies but in some also of those that are consistent there may perhaps be more motion in the insensible parts than our senses discern or we are wont to imagine especially in those bodies which having been once endowed with life are though not fluid yet either soft or at least not perfectly hard I have more than once taken pleasure to look upon an heap of swarming Bees for though they make not up a liquid but coherent body which may be turn'd upside down without losing its coherence and which being beheld at a distance seems to be one entire mass or body yet it is evident to him that looks at them near enough that the particular Bees that swarm have most of them their distinct and peculiar motions and that yet these motions of the particular Bees destroy not the coherency of the heap because that when one of the more innermost Bees removes as she lets go her hold from those that she rested on before and goes away from those that rested on her so she meets with others on which she may set her feet and comes under others that in like manner set their feet on her and so by this vicissitude of mutual supports their coherence and their removes are made compatible and if instead of Bees the swarm consisted of extreamly little flies their particular motions would perhaps be inconspicuous And that some such thing may happen in the consistent bodies we have been speaking of seems probable from hence that in wainscot and other hard wood we often see little heaps of dust produc'd in them by putrefaction and not only in Cheese we many times see multitudes of mites start up but in Apples and other Fruits we oftentimes find Magots though the skin be whole which could not be unless the parts of the matter were variously transpos'd that is put into a local motion and connected after a manner suitable to the Nature of the infect to be produc'd And by the growth of bones in the bodies of perfecter Animals as well in respect of the internal cavity where the marrow lodges as of the external surface as also by the growth of the shells of Oysters and Snails though cold Animals from a size inconsiderable at first in regard of what is afterwards attain'd to and by some other resembling particulars it seems that the small particles that constitute even the solid parts of Animals are not whilst the Creature lives or at least whilst it grows altogether exempt from some though slow and insensible local motion And I remember that it has by a very diligent observer been affirmed to me that he saw several pieces of Gum swet out of an old wainscot of above twenty years standing Which I the less wonder at because I have several times seen viscous Exsudations disclose themselves like drops of Turpentine upon Deal-boards which had been made use of about Buildings But of this subject more perhaps elsewhere SECT XXVIII After we have hitherto discours'd of Fluidity as consider'd in distinct Bodies we might properly enough say here something of what furtherance or hinderance in respect of Fluidity one Body may receive by being mingl'd with another But the consideration of those changes of Consistence which may be produc'd by Mixture is a Subject that we shall have such frequent occasions to treat of in what we are to deliver about Firmness that we shall now only give this general Admonition That 't is not so safe as one would think to fore-tell the consistence of a mixture of two or more Bodies from the bare consideration of the consistence of those Bodies whereof it is to be compounded And that we might at once both manifest this and insinuate what Judgment should be made of what is said by so many Chymists and others who without Limitation teach That the Addition of Salts to metalline and mineral Bodies does much facilitate their fusion I remember I purposely made and employ'd this Experiment We dissolv'd crude Copper in a due quantity of Spirit of Nitre and by Evaporation reduc'd the Solution to a kind of Vitriol of a lovely colour We also corroded with two parts of Spirit of Nitre one of good Tin and suffer'd the mixture to reduce it self as it easily did to a substance almost like Meal Of this mixture we put a parcel into a Crucible and suffer'd it to grow and for a pretty while to continue red hot Nay we put some of it upon a quick coal and excited the heat by frequently
together the lowermost of them or the appendant weight were fasten'd to the ground For in this case there appears no reason to believe that their power to resist separation would be less than it was before And yet it seems evident that the uppermost Marble would not be perpendicularly pull'd up but by such a force as were at least I say at least able to lift up a weight equal to that of the last mention'd Marble and of a Pillar of Air having the Stone for its Base and reaching to the top of the Atmosphere since at the instant of Revulsion before the Air can get in and spread it self between the Stones there is not for ought appears any such Body under the upper Marble as can help the hand to sustain the weight both of that Marble and the incumbent Cylinder of the Atmosphere which then gravitates upon it and consequently upon the hand becâ—use there is no Air nor other equivalent Body underneath it to sustain its part of the weight as the lower Air is wont to do in reference to the heavy Bodies that lean on it and to the weight of the incumbent Air. And therefore we need not much marvel if when only a less weight than that of the foremention'd Pillar of the Atmosphere hangs at the lower Marble it should be capable of being drawn up by the uppermost rather than suffer a divulsion from it As we see that when two Bodies being fasten'd together are endeavour'd to be drawn asunder by forces or weights not able to separate them they will usually both of them move that way towards which either of them is the most strongly drawn On which occasion I remember what I have sometimes observ'd in one of the wayes of trying the strength of Load-stones For if the Load-stone be able to take up more than its own weight you may as well lift up the Load-stone by a Knife as the Knife by the Load-stone And though one accustom'd to judge only by his Eyes would have imagin'd that when I held the great weights formerly mention'd suspended in the Air there was no strong endeavour to pull up the upper Marble from the lower because my hand being for a while held steddy seem'd to be at rest yet he will easily be invited to suspect that in such a thought there may be a great mistake who shall consider that neither did the weight sensibly appear to pull the lower Marble downwards though my hand assur'd me that the weight had not lost its Gravitation And if I shall adde that once when the weight after having been lifted up into the Air was casually so loosen'd from the upper Marble as suddenly to drop down my hand unawares to me was by the force of that Endeavour it just before employ'd to sustain the fallen weight carried up with such violence that I very sensibly bruis'd it by the stroak it gave against the face of a By-stander who chanc'd out of curiosity to hold his Head over the Marbles And here it will not be impertinent to bring in an Experiment that I once devis'd not only for other uses but to illustrate the subject we have been hitherto treating of The Tryal I lately found registred among my Adversaria in these Termes A Brass Valve of about an Inch Diameter was with Cement well fastned to the shorter Leg which was but of very few Inches in Length of a long Glass Syphon left open at the end of the other Leg. This Valve being let down to the Bottom of a tall Glass Body full of water so that 't was if I much mis-remember not between a Foot and half a yard beneath the surface of the water when there was let in as much water into the Pipe as reach'd in that as high as the surface of the External Water in the Tall Cucurbite Then about an Ounce weight was put into the opposite Scale of a Ballance to the neighbouring Scale whereof one end of a string was tyed whose other end was fastned to the said Valve whose parts would be thereby drawn asunder But when the water was empty'd out of the Pipe and the Valve was let down to the former depth there was requisite about 5 Ounces that is 4 Ounces more than formerly to disjoin the parts of the Valve and let the water get in between And when the Syphon being freed from water the Valve was listed higher and higher together with the Pipe there needed less and less weight to make a Disjunction two Ounces of Additional weight to the one Ounce requisite to counterpoize the Cover of the Valve it self on the water sufficing to lift up the Cover when the Valve was held about half way between its Lower station and the Top of the water a single Ounce sufficing afterwards and half an Ounce of Additional weight proving enough to disjoin the parts when the Valve was held but a little beneath the surface of the Liquor This relation of an Experiment which I afterwards show'd to many Virtuosi will perhaps seem somewhat dark to you without a Scheme but if you consider it attentively enough to apprehend it throughly I presume it will show you that whether or no there be upon any other score a repugnancy to the separation of smooth Bodies join'd by immediate contact yet certainly there may be a great Repugnancy upon the bare Account of the Gravity of the medium wherein the Divulsion is attempted For in our case the Fuga Vacui if there be any ought to resist the separation of the Parts of a Valve still kept under water as much near the Top of the water as at the Bottom And therefore the great difference found in that resistance at those different places may be attributed to the Pressure of the Ambient water that thrust them together And though it be true that Air is an Exceeding Light Body in comparison of water yet in divers Tryals I have found the Disproportion in Gravity of those two Fluids not to exceed that of a 1000. to 1. So that considering how many miles not to say scores of miles the Air may reach upwards there seems no absurdity at all to suppose that the bare Pressure of it against the Marbles formerly mention'd may keep them as coherent as we found them to be But since this I have been able to make an Experiment that does sufficiently confirm the former Doctrine For having suspended the two coherent Marbles in a Capacious Glass whence by a certain contrivance the Air could little by little be drawn out we found as we expected that whilst there remain'd any considerable quantity of Air in the Glass the lower Marble continued to stick to the other the Pressure of the remaining Air though but weak being yet sufficient for the sustentation of the lower Marble which it was not after the Air was further withdrawn And if when the Disjunction was made the upper Marble were by another contrivance let down upon the lower so as to
and adequate Redintegration is yet not far from being a real one the dissipated parts of the Concrete truly re-uniting into a body of the same nature with the former though not altogether of the same bulk SECT XXXIV And yet I think it requisite to represent to you Pyrophilus that Salt-Petre is a body whose parts are not Organical and which is not so much as very compounded and that therefore bodies that consist of more numerous Ingredients and much more those whose Organical parts require a much more artificial and elaborate disposition or contrivance of their component particles cannot be safely judg'd of by what is possible to be perform'd on a body of so simple and slight a contexture as is Salt-Petre for we see that even wine though no organical body nor so much as the most compounded of inanimate Concretes when it 's spirit is though by the gentlest distillation drawn from it will not by the re-union of it's constituent Liquors be reduc'd to it's pristine Nature because the workmanship of Nature in the disposition of the parts was too elaborate to be imitable or repairable by the bare and inartificial apposition of those divided parts to each other besides that in the dissociating action even of the gentlest fire upon a Concrete there does perhaps vanish though undiscernedly some active and fugitive particles whose presence was requisite to contain the Concrete under such a determinate form as we see in Wine degenerating into Vinegar where the change seems to proceed from this that upon the Avolation or if I may so speak Depression of some subtle sulphureous spirits whose Recesse or degeneration is not to be perceiv'd by any sensible diminution of bulk in the Liquor the remaining parts fall into new leagues or dispositions and constitute an acid Liquor somewhat fix'd and Corrosive and consequently of qualities very differing from those of the Wine whose souring produc'd it as we more fully declare in our Experiments relating to Fermentation SECT XXXV And certainly there is as we formerly said so artificial a contrivance of particles requisite to the constitution of the Organical parts of living bodies that it will be scarce possible for humane Art or Industry to imitate so as to equal those exquisite productions of Nature And therefore I wonder not that the story of the Phoenix's resurrection out of her own ashes should by the best Naturalists be thought a meer fiction And if that relation mention'd by the inquisitive Kircherus as an eye-witness of the Reproduction if I may so call it of Shell-fishes near the brink of a Lake in the Sicilian Promontorie Peloro by the watering of their broken bodies with Salt water in the Spring be strictly true it seems much more improbable that such changes and vicissitudes should be bare Redintegrations of the dissociated parts of such restored bodies than that according to what we elsewhere teach they should be New Productions made by some seminal particles undiscernedly lurking in some part of the destroyed body and afterwards excited and assisted by a Genial and cherishing heat so to act upon the fit and obsequious matter wherein 't was harbor'd as to organize and fashion that disposed matter according to the exigencies of it's own Nature For that in some bodies the Seminal particles may a while survive the seeming destruction of life is not altogether without example as we elsewhere professedly manifest And in Kircher's story it is to be observ'd that the restor'd Animals were but Shell-fish in whose slimy and viscous substance the Spirits and Prolifick parts are probably both more diffused and kept from being easily dissipable to which I know not whether it will be worth while to subjoyn that in such Fishes the Mechanical contrivance is but very plain and as it were slight and obvious in comparison of the exquisitely elaborated parts of more perfect Animals SECT XXXVI The last observable Pyrophilus that we shall at present take notice of in our Experiment shall be this That it may thereby seem probable that some Chymical remedies may be too rashly rejected by Physicians because Oyl or Spirit of Vitriol Aqua Regis or other Corrosive Liquors have been employ'd in their preparation For it is confidently affirm'd by many Physicians and but faintly denied by some Chymists that the Corrosive Menstruums made use of in the preparation of remedies can never be so exquisitely wash'd off from them but that some of the Salts will adhere to the Medicines and perniciously display their Corrosive Nature in the body of him that takes them And it is not to be denied but that many ignorant and venturous Chymists do unskilfully and therefore dangerously enough imploy Corrosives sometimes without any necessity or real advantage to invite them to it and sometimes withouâ— sufficiently freeing their Medicines from the corroding Salts by whose assistance they were prepar'd for 't is not always the frequency of ablutions though with warm water that will suffice to carry off the Salts from some bodies and therefore those great Artists Helmont and Paracelsus prescribe some things to be dulcifi'd by the abstraction of the water of whites of Egges which though it seem insipid hath been found a great disarmer of corrosive Salts and others by the frequent distillation of Spirit of Wine which indeed not to mention the Balsamick parts it may leave behind we have observ'd to have a faculty of carrying up with it the Saline Particles of Spirit of Vinegar adhering to some Chymical remedies But all this notwithstanding Pyrophilus there may be several bodies and perhaps more than are commonly taken notice of which quite alter the nature of the acid Salts employ'd to prepare them by occasioning those Salts to degeneraâ—e into another nature upon the very act of corroding or else by so associating their own Salts with those of the dissolving Menstruum that from the Coalition of both there emerges a third body differing in qualities from either As in our experiment we find that the Spirit of Petre which is much more sharp and corrosive than the strongest distill'd Vinegar and the fix'd Nitre which is Caustick like Salt of Tartar and may I suppose well serve for a Potential Cautery as Surgeons speak do by their mutual action work themselves into Salt-Petre which is far enough from having any eminently fretting Quality and may be safely taken inwardly in a much greater Dose than either of its Ingredients SECT XXXVII How much corrosive Salts may dulcifie themselves by corroding some bodies you may easily try by pouring distill'd Vinegar or moderate Spirit of Vitriol upon a competent proportion of Corals or Crabs Eyes or Pearls or as I suppose almost any testaceous body And for my part though I am very shy of imploying corrosive Liquors in the Preparation of Medicines yet I have lately given a Preparation of refin'd Silver made with Aqua fortis it self or Spirit of Nitre not onely innocently but with such success that a couple of Experienc'd
the particular opinions wherein the Atomists differ from other modern Naturalists especially since he has on some occasions plainly enough intimated the contrary by proposing together with the Atomical ways of resolving a thing another Explication more agreeable to the Cartesian or some other modern Hypothesis The following Tract was entitl'd a History of Fluidity and Firmness because indeed the having set down Experiments and other matters of fact relating to the Subjects treated of is the Main though not the Only thing the Author dares pretend to have done in it And he stiles the History as it now comes abroad Begun Partly because he would invite abler Pens to contribute their Observations towards the compleating of what he is sensible he has but begun and partly because he may hereafter if God permit do something of that kind himself And lastly the Author though troubl'd that he can do it dares not but Advertise the Reader That some Pages partly a little after the beginning and partly about the middle of the following Treatise having been lost through the negligence or mistake of him to whose Care the sheets whereon it was written were committed he fears he has not been able otherwise than very lamely and imperfectly to repair that loss out of his Memory THE HISTORY OF Fluidity and Firmness The First Part. Of FLUIDITY SECT I. WHether Philosophers might not have done better in making Fluidity and Firmness rather States then Qualities of Bodies we will not now examine But under which soever of the two Notions we look upon them 't is manifest enough that they are to be reckon'd amongst the most general Affections of the Conventions or Associations of several particles of matter into Bodies of any certain denomination there being scarce any distinct portion of matter in the World that is not either Fluid or else Stable or Consistent And therefore I presume it may be well worth while to consider what may be the general causes of these two States Qualities or Affections of Matter and to Try whether by associating Chymical Experiments to Philosophical Notions there may not be given at least a more Intelligible and more Practical of both these Subjects than has been hitherto afforded us by the Doctrine of the Schools which is wont to appear very unsatisfactory to discerning Men many of whom look upon what is wont to be taught by the Peripateticks concerning Fluidity and Firmness as well as other Qualities to be partly too general to teach us much and partly too obscure to be understood And that which at present invites us to this Enquiry is chiefly that some Circumstances of our Authors Experiment touching Salt-Petre may afford us some useful assistance in our designed search For though the chief Phaenomena and Circumstances of the Experiment may be thought principally to respect Fluidity yet since that and Firmness are contrary Qualities and since it is truly as well as commonly said That contraries survey'd together serve to illustrate each other it may reasonably be hop'd That the Light which the circumstances just now related to may give to the Nature of Fluidity may facilitate the knowledge of that of Compactness nevertheless we shall often be oblig'd to treat of these two qualities together because the Experiments we are to produce do many of them relate to both SECT II. A Body then seems to be Fluid chiefly upon this account That it consists of Corpuscles that touching one another in some parts only of their Surfaces and so being incontiguous in the rest and separately Agitated to and fro can by reason of the numerous pores or spaces necessarily left betwixt their incontiguous parts easily glide along each others superficies and by reason of their motion diffuse themselves till they meet with some hard or resisting Body to whose internal surface by virtue of that Motion their Smallness and either their Gravity or something Analogous or Equivalent to it they exquisitely as to sense accommodate themselves SECT III. What notion Epicurus and the Antient Atomists his followers had of fluid Bodies may be learn'd from these Verses of his Paraphrast Lucretius Illa autem debent ex laevibus atque rotundis Esse magis fluido quae corpore liquida constant Nec retinentur enim inter se glomeramina quaeque Et procursus item in proclive volubilis extat And indeed it is probable enough that in divers Liquors the little surfaces of the component particles are smooth and slippery and that their being so does much facilitate the gliding of the Corpuscles among themselves and consequently the Fluidity of the Body they compose Nor is it to be deny'd that the Spherical figure of such Corpuscles may also conduce to their easie rouling upon one another but there are divers other figures which may make the little Bodies indow'd with them voluble enough to constitute a fluid substance And the other qualities to be met with in divers liquid substances and even in water it self and Oyl seem to argue their parts to be otherwise shap'd and those fluid Bodies which are not Liquors as Air and Fire seem to be compos'd of particles not all or most of them round but of very various and sometimes of very irregular figures and yet that such Bodies deserve to be call'd fluid ones will be manifest anon And that they make a much more considerable part of the Universe than those that are wont to be call'd Liquors may be argu'd from hence that except the Earth the Planets and perhaps too the fixt Stars the rest of the World as vast as it is seems to consist chiefly if not only of an Aetherial thin and fluid substance as may appear to omit other arguments by what latter Astronomers have observ'd concerning the free and unresisted motion of such Comets as have by a Trajection through the Aether for a long time wander'd through the Celestial or Interstellar part of the Universe SECT IV. And here let us observe that 't is not necessary to the Fluidity of a Body nay nor to its appearing fluid to the Eye it self That the Corpuscles it consists of be crowded as close together as they are wont to be in water and other bodies that are commonly lookt upon as the only Liquors For though a parcel of matter no bigger than a grain of Corn being rarify'd into smoak will possess an incomparably greater space than it did before and though if a Body be further rarify'd into flame its expansion will be yet much greater yet both smoak and flame may be so order'd as to appear like Liquors We have practis'd divers ways to make the fumes of Bodies acquire a visibly-level superficies like water but the easiest though not perhaps the best is this part of which I remember I have seen perform'd as a kind of trick by a very ingenious Person The mouth being fill'd with the smoak of Rosemary that happening to be at hand when I made the Experiment if this smoak be plentifully blown into a
especially their gravity at least here about the Earth equally depressing and thereby levelling as to sense their uppermost superficies they must necessarily move to and fro till their progress be stopt by the internal surface of the Vessel which by terminating their Progress or Motion toward the same part does consequently necessitate the Liquor those little Bodies compose to accommodate it self exactly for ought the Eye is able to discern to the contrary to its own figure SECT XV. This short and general Account of Fluidity may we hope be as well further explicated and illustrated as confirmed by the following Instances and Experiments and therefore we shall forthwith proceed to Them And it will be fit to mention in the first place those that are afforded us by the Body our Author treats of Salt-Petre they having occasioned our writing about this Subject Salt-Petre then may be made fluid two several wayes either by or without a Liquor By the intervention of a Liquor it puts on the form of a fluid Body when being dissolv'd in water or aqueous juices it is not by the Eye distinguishable from the solvent Body and appears as fluid as it which seems to proceed from hence that the agitated particles of the water piercing into the joints or commissures of the Corpuscles of the Salt do disjoyn them and thereby divide the Nitre into parts so small that it is easie for those of the water wherewith they are associated not only to support them but move them to and fro whence it comes to pass that these Particles being so small and swimming some one way some another in the yielding body of water make no such resistâ—nce against the motion either of a mans hand or other external Body that strives to displace them as they did in their saline form But that with much less Liquor a Nitrous body may be rendred fluid may appear to him that shall expose such fix'd Nitre as our Author teaches to make to the moist Air of a Cellar For there it will run per deliquium as Chymists speak into a Liquor which consists of no more aqueous Particles than are necessary to keep the saline ones which seem to be much smaller than those of unanalyz'd Nitre in the agitation requisite to Fluidity SECT XVI And hence we may proceed to consider what Fluidity Salt-Petre is capable of without the intercurrence of a Liquor and this may be two-fold For first if it be beaten into an impalpable powder this powder when it is pour'd out will emulate a Liquor by reason that the smallness and incoherence of the parts do both make them easie to be put into motion and make the pores they intercept so small that they seem not at a distance to interrupt the unity or continuity of the Mass or Body But this is but an imperfect Fluidity both because the little grains or Corpuscles of Salt though easily enough moveable are not alwaies in actual motion and because they continue yet so big that both they and the spaces intercepted betwixt them are near at hand perceivable by sense But if with a strong fire you melt this powder'd Nitre then each of the saline Corpuscles being sub-divided into I know not how many others and these insensible parts being variously agitated by the same heat both which may appear by their oftentimes piercing the Crucible after fusion wherein they lay very quietly before it the whole body will appear a perfect Liquor and be thought such by any Beholder that shall judge of it but by the Eye and such also is the Fluidity of melted metals in which when they are brought to fusion in vast quantities I have seen the surface wav'd like that of boyling water and sometimes parcels of Liquor thrown up a pretty way into the Air. And not only Fire and other actually and manifestly hot Bodies are able to make some hard ones fluid but it seems also that some bodies may be brought to Fluidity by others which to the touch appear cold if they be but fitted to change the texture of the hard body and put its inflected parts into a convenient motion as may be seen in the Chymical Experiment of turning the brittle body of Camphire into an Oyl for the time by letting it lye upon Aqua fortis which perhaps bends and complicates the formerly rigid particles and puts them into such a motion that they do as well glide along as somewhat twine about each other And I further try'd not having found it mention'd by the Chymists that Camphire may by a dexterous application of heat be brought in close glasses both to flow and to boyl almost like Oyl 'T is true that these Liquors taken from the fire quickly lose that name and grow solid again But the duration of a thing is not always necessary to denominate it such for the Leaf of a Tree for instance whilst it flourishes may be as truly green as an Emerald though the leaf will after a while wither and turn yellow which the stone will never do and in cold Climates where Lakes c. at other times navigable are sometimes frozen so hard that Carts and ev'n great Ordnance may safely be drawn over them Ice and water are the one a stable and the other a liquid Body notwithstanding that the same portion of matter which at one time is frozen into a hard and solid substance was a little before a fluid Body and now and then in a very short time will be thaw'd into a Liquor again SECT XVII I know not whether it be requisite to take notice that the Fluidity which Salt-Petre acquires upon fusion by fire seems very much of kin to that which is acquir'd by solution in water But if fusion be made rather by the Ingress and transcursions of the atoms of fire themselves than by the bare propagation of that motion with which the agitated particles that compose fire beat upon the out-side of the vessels that contain the matter to be melted in such case I say both those kinds or manners of Fluidity newly ascrib'd to Salt-Petre will appear to be caus'd by the pervasion of a foreign body Only in dissolution the fluid body is a Visible and Palpable Liquor and consequently more gross whereas in fusion the fluid substance that permeates it is more thin and subtil and divides it into much smaller parts and so adds very little to its bulk SECT XVIII But because some scruple may possibly arise about this matter from hence that the powder of Nitre how fine soever seems fluid but just whilst it is pouring out and ev'n then is but very imperfectly so and that as for fusion that is wont to reduce the melted body to a new and permanent state as the formerly-mention'd powder of Salt-Petre which before fusion was but a heap of incoherent particles is by it made a solid and considerably hard Body to prevent I say or remove such scruples we will set down one Experiment that
Flanders near Tournay a certain sort of ashes of Lime made of Marble which was excellent for any kind of work made in the water For having made a Bed of great stones they cast upon them whole Baggs full of such ashes instead of Mortar and the water betwixt the stones having temper'd up these ashes petrify'd them to that degree that in a short time they became as hard as Marble Thus far He. But to pursue our former Discourse That also which we intimated of the conduciveness of the various tumblings to and fro of the hard particles to their uniting into one firm concretion seems confirmable by what we have observ'd in some saline Liquors especially certain parcels of Spirit of Harts-horn which whatever were the constitution of the ambient air remâ—ind fluid some of them for many months after which the saline Corpuscles began to shoot at the bottom of the remaining Liquor into exquisitely-figur'd Crystals which at length grew copious enough For this spontaneous coagulation of the little saline Bodies happening so late it seemed that it was preceded by almost innumerable evolutions which were so many and so various that at length the little bodies came to obvert to each other those parts of themselves by which they might be best fasten'd togetâ—â—â— and constiâ—ute a firm body Which conjecture seem'd tâ—â— less improbable because we could not well imagine thâ—â— this coagulâ—tion proceeded as that of dissolv'd Allum and other Salâ—s is wont to do from the evaporation of the superfluous Liquor for the Glasses wherein what we have mentioned happen'd being carefully stop'd there was no danger of such an avolation and if any thing could get away it must have been the subtil peircing and fugitive Spirit which indeed as my Nose had inform'd me does oftentimes penetrate ordinary stopples for the flying away of those volatile parts would only have left the remaining Liquor more aqueous And 't is well known to those that deal with such kind of Liquors that the more aqueous they are the lâ—ss apt they are to Crystallize And however it will serve our turn that there was but an insensible diminution of the Liquor upon the recesse of whatever it was that got through the Cork To the same purpose I remember also that having in a Crystal Vial carefully kept a pretty quantity of well-colour'd Tincture of Amber made with pure Spirit of Wine it remain'd fluid for a year or two and during that time presented us with a strange Phaenomenon that belongs to other papers But having been absent for two or three years from the place where we lock'd it up we found when we came again to look upon it that that though it had formerly remain'd fluid so long yet several yellow lumps of Amber almost like Beads with one side flat had here and there fasten'd themselves partly to the bottom and partly to the sides of the Glass the rest of whose internal surface continues yet transparent Another thing whereby bodies become stable is the admission of adventitious Corpuscles into their Pores and recesses And of the wayes by which these foreign Corpuscles may bring the substance they invade to be compact these four appear the chief First then the adventitious Corpuscles we speak of may produce stability in the matter they pervade by expelling thence those voluble particles which whilst they continu'd in it did by their shape unfit for cohesion or by their motion oppose the coalition or disturb the Rest of the other particles whereof the Body consisted But of this having already discoursed proceed we to what is to follow In the next place then foreign Bodies may contribute to the stability of a substance they get into by hindering the motion of the little Bodies that constitute it And thirdly such advenient Bodies especially if they be not of the smallest size may produce a firmness in the substance which they get into by constituting with the particles it consists of Corpuscles more unapt for motion and fitted for mutual cohesion These two we mention together because that very often Nature imploys them together for the introducing of stability into Matter To these seems to be reducible the way of turning the fluid body of milk into cruds by the mixture of a little Runnet whose saline particles pervading the body of the milk do not only make a commotion in the parts of it but fasten the branched particles of it to one another and with them constitute a body of another texture than was the milk and the weight of these crudled bodies reducing them by degrees into a closer order does whilst it presses them together squeeze out the thinner and more serous Liquor which the Runnet was unable to coagulate and which being thus sever'd from the grosser parts of the milk may well be more fluid than milk it self is wont to be And that there is some coalition of the particles of the Runnet with the coagulated ones of the milk may appear by the complaints that Houswives sometimes make of their Dairy-maids that the Cheeses tast too strong of the Runnet when too great a proportion of it has been mingled with the milk And though we ascrib'd the crudling of the milk to the saline particles of the Runnet we ignore not that not only common Runnet but also diverse juices of herbs will crudle milk as is well known in thole parts of Italy where Cheese is made without Runnet But we made especial mention of the saline Corpuscles of the Runnet because really Houswives are wont to salt it and because saline Liquors do manifestly and powerfully operate in the coagulation of milk which may be crudled by juice of Limons and I know not how many other Acid Salts And to manifest yet further the coagulative power of them we have sometimes in about a minute of an hour arrested the Fluidity of new milk and turn'd it into a crudle substance only by dexterously mingling with it a few drops of good Oyl of Vitriol But of the effects of various Salts upon milk we elsewhere may and therefore shall not now discourse Between this last recited Expâ—riment and the two following ones 't will not be improper to insert the immediately ensuing one for the Affinity which it seems in different respects to have with both I remember then that I divers years ago prepar'd a Salt which either was or at least answer'd well to the qualities ascrib'd to that which is now called Glauberus's Sal Mirabilis which seem'd to have in it a coagulative power in reference to common Waâ—er For whereas Salt of Tartar Common Salt Niâ—re c. being dissolv'd in Water do upon evaporation of a sufficient quantity of â—hat Water recover indeed their pristine Saline Forms yet they do but coagulate themselves without concoagulating with them either any Water or at least so much as Chymists have thought worth the takiâ—g noâ—ice of Whereas this Salt we speak of being pâ—epar'd for the purpose and dissolv'd
the air though but in a Chamber I found its surface powder'd with little grains of Vitriol as both their Colour and their Taste inform'd me Now whether or no we suppose that the fire did put the parts of the Amalgama into any lasting Agitation yet the Mass being almost fluid after it was taken from the fire its parts may according to our notion of Fluidity be well suppos'd to have some kind of motion among themselves and it will not be deni'd that the fire might concur with othâ—r things to make that motion convenient to cause the parts to fasten themselves to one another For that â—he motion wherein a soft and almost fluid Body is once put may possibly tend to harden it long after that motion seems to be extinct may be made probable by what has been affirm'd to me by eminent and experienced Masons namely that the best sort of Lime made into Mortar will not have attain'd its utmost compactness till twenty five or thirty years perhaps not till three or fourscore after it has been imploy'd in Building and this is given me as one of the Reasons why in the demolishing of antient Fabricks it is sometimes more easie to break the stone than the Mortar And lastly that we also made mention of the Texture resulting from the mingled Ingredients of our Amalgam we might justifie by saying that having changed the proportion of the Quick-silver to the Verdigreese we found that the Amalgam coagulated much more slowly and when it was coagulated was much less hard than when one used the quantities above specify'd Here I should put a period for the present to this Discourse but that having in a late Writer met with a notable Observation of the natural Induration of a soft Body I think it worthy to be here annex'd partly because the French Book is not common no more than the Observation and partly that by conferring together this natural Induration with that Artificial one freshly mention'd it may the better appear how Nature and Art have sometimes resembling operations in rendring Bodies solid My Author then by name Pierre Pelleprat being not long since sent with some other Jesuites upon the laudable errand of Preaching the Gospel to the Indians of the Southern America has among other things this passage in the short Relation he makes of the American Continent There is says he one thing worthy of Observation neer the mouth of this great river he speaks of that of the Amazons which is That men find there a kind of green Clay that is soft as long as 't is in the water so that one may print on it all kind of Figures and give it what shape one pleases but when it is expos'd to the Air it hardens to that degree that Diamonds are not much harder than the stones it affords I have adds he seen Hatchets made of this Clay which the Savages employ'd to cut Wood with when they had not the use of ours c. And now at last I see 't is time to put a period to a discourse that has been unawares lengthned far too much already But yet I think you will easily pardon me if I conclude it not abruptly but with the recital of an Experiment which having had the honour to be seen as to the main part of it by an illustrious meeting of Curious Men their having been pleas'd to speak very advantagiously of it to others excited a curiosity among them to know by what artifice effects that were so uncommon had been produc'd The Scope therefore and the manner of making the Experiment were in short as follows Being desirous to shew how much Fluidity and Firmness may depend upon the Texture and upon the Motion or Rest of the insensible parts of Bodies I first make with good Spirit of Vinegar a Solution of Coral so strong that when 't is filtrated and cool'd it will commonly after some time begin to have a kind of Sediment at the bottom the clear Liquor I gently pour off when the Experiment is to be made and to this I put a convenient proportion of very well dephlegm'd Spirit of Wine which if it be pour'd on very slowly and warily may be made for a pretty while to swim upon it in the form of a distinct Liquor but if by a few shakes I mingle them together they will presently unite into a Concretion of which when the Experiment succeed very well as it did when I shew'd it to the above-mention'd Assembly not one drop will fall to the ground upon turning up the wide mouth Glass it should be made in and holding it with the mouth directly downwards And this so hastily produc'd consistence may be durable enough if it be carefully lookt to But to dispatch the whole Experiment in a short time I take a little strong Spirit of Nitre which perhaps is not needful if good Aqua Fortis be at hand and putting about an equal or other convenient quantity of it to this Mixture I nimbly stir it and the Spirit together whereupon the Whole is reduc'd in a very few minutes to a transparent Liquor N. B. Though I have divers times made and shewn this Experiment yet there are so many Circumstances requisite to make the first part of it succeed very well for to make it succeed in some measure is not so difficult that the event has sometimes deceiv'd me in spite of the several Tryals I have made Wherefore 't will not be amiss to intimate First That one of the first times if not the first I made such an odd Concretion was with the Solution not made with Spirit of Vinegar but with Spirit of Verdigrease which I commonly distil without additament though afterwards I was invited to prefer strong Spirit of Vinegar which was the Liquor wherewith the recited Experiment was exhibited Secondly That it often happens that if the Solution of Coral which is not the only body wherewith I have made such Tryals with indifferent good success be not sufficiently strong and impregnated with Saline parts or the Spirit of Wine be not sufficiently rectify'd the shaking of the two Liquors will not change the consistence of the whole mixture but leaves some part of it fluid or else the Concretion will not begin presently to be made but require to be waited for a while Thirdly That I once at least if not oftner observ'd that when by mingling the two Liquors and shaking them in a narrow mouth'd Glass whose Orifice was stopt they would not concoagulate as it was confidently expected they should yet by trying the Experiment in a wide mouth Glass to which the Air had free access it succeeded to my content Fourthly That in the Reduction of the Concretion to a fluid Body 't is not proper to employ in stirring it a Knife or any other Metalline Body except it be of Gold but rather some Stick of Glass or at least some clean Stick of Wood lest the Menstruum should corrode it and