much of the water consisting perhaps of Corpuscles more pliant to the internal surfaces of the glass was contiguous to the sides it was shown that in case the little Glass-Vessel that held the water of which a part ascended into the slender Pipe were so closed that a man might with his mouth suck the Air out of it the water would immediatly subside in the small Pipe And this would indeed infer that it asscended before only by the pressure of the incumbent Air. But that it may how justly I know not be objected that peradventure this would not happen in case the upper end of the Pipe were in a vacuum And that 't is very probable the water may subside not because the pressure of the internal Air is taken off by exsuction but by reason of the spring of the external Air which impels the water it finds in its way to the Cavity deserted by the other Air and would as well impel the same water upwards as make it subside if it were not for the accidental posture of the Glasses However having not now leisure to examine any further this Matter I shall only mind your Lordship that if You will prosecute this Speculation it will be pertinent to find out likewise Why the surface of Water as is manifest in Pipes uses to be concave being depressed in the middle and higher on every side and why in Quick-silver on the contrary not only the surface is wont to be very convex or swelling in the middle but if you dip the end of a slender Pipe in it the surface of the Liquor as 't is called will be lower within the Pipe than without Which Phaenomena whither and how far they may be deduced from the Figure of the Mercurial Corpuscles and the Shape of the Springy Particles of the Air I willingly leave to be considered An Attempt for the Explication of this New Experiment MY former Conjecture That the unequal height of the surfaces of the water proceeded from the greater pressure made upon the water by the Air without the Pipes A. B. C. than by that within them I shall endeavour to confirm from the Truth of the two following Propositions The first of which is That an unequal pressure of the incumbent Air will cause an unequal height in the waters Surfaces And the Second is That in this Experiment there is such an unequal pressure Now that the First is true the following Experiment will evince For if you take any Vessel so contrived as that you can at pleasure either increase or diminish the pressure of the Air upon this or that part of the Superficies of the water the equality of the height of those parts will presently be lost And that part of the Superficies that sustains the greater pressure will be inferiour to that which undergoes the less A fit Vessel for this purpose will be an inverted Glass Syphon such an one as is described in the Sixth Figure For if into it you put a quantity of Water suppose enough to fill it as high as the Line A. B. and applying your mouth to one end as to D. you shall find that by gently blowing in at it you shall depress the Superficies B. and thereby raise the opposite Superficies A. to a considerable distance and by gently sucking you may perceive the clean contrary effects produced Next That there is such an unequal pressure I shall prove from this that there is a much greater inconformity or incongruity call it what you please of Air to Glass and some other Bodies than there is of Water to the same What I mean hereby I shall in short explain by defining conformity or congruity to be a property of a fluid Body whereby any part of it is readily united or intermingled with any other part either of it self or of any other Homogeneal or Similar fluid or firm and solid body And unconformity or incongruity to be a property of a fluid by which it is kept off and hindred from uniting or mingling with any heterogeneous or dissimilar fluid or solid Body This last property any one that hath been observingly conversant about fluid Bodies cannot be ignorant of For not now to mention several Chimical Spirits and Oyles which will very hardly if at all be brought to mix with one another insomuch that there may be found some 8 or 9 or more several distinct Liquors which swimming one upon another will not be brought to mix we need seek no further for Examples of this kind than to observe the drops of rain falling through the air and the Bubbles of air which are by any means conveyed under the surface of the Water or a drop of common Sallet Oyl swimming upon water In all which and many more Examples that might be enumerated of this sort the incongruity of two fluids is easily discernable And as for examples of Congruity or Incongruity of Liquids one with another or with several kinds of firm or solid Bodies they have long since been taken notice of and called by the Names of Drieness and Moysture though these two Names are not comprehensive enough they being commonly used to signifie only the adhering or not adhering of water to some other solid Bodies of this kind we may observe that water will more readily wet some woods than others and that water let fall upon a Feather the whiter side of a Colwort and some other leaves or upon almost any unctuous or resinous superficies c. will not at all adhere to them but easily tumble off from them like a solid Bowl whereas if dropt upon Linnen Paper Clay green Wood c. it will not be taken off without leaving some part of it behind adhering to them So Quicksilver which will very hardly be brought to stick to any vegetable body will readily adhere to and mingle with several clean metalline bodies Now from what cause this congruity or Incongruity of bodies one to another does proceed whether from the Figure of their constituent Particles or interspersed pores or from the differing motions of the parts of the one and the other as whether circular undulating progressive c. whether I say from one or more or none of these enumerated causes I shall not here determine It being an enquiry more proper to be followed and explained among the general Principles of Philosophy whither at present I shall refer it as fearing lest it might here seem absurd without the concatenation of several other Principles to explicate it and knowing it likewise sufficient for this enquiry to shew that there is such a property from what cause soever it proceeds These Properties therefore alwaies the concomitants of fluid bodies produce these following visible Effects First They unite the parts of a fluid to its homogeneal Solid or keep them separate from its heterogeneal Hence Quicksilver will as we noted before stick to Gold Silver Tin Lead c. and unite with them but roule off from wood stone glass
know a more likely hypothesis for gravity which I can make out by experiment I shall at present proceed to other Queries contenting my self to have here only given a hint of what I may elswhere determine A Third Query then was whether the heterogeneity of the ambient fluid may not be accounted a secondary cause of the roundness or globular form of the greater bodies of the world such as are those of the Sun Stars and Planets the substance of each of which seems altogether heterogeneous to the circum-ambient fluid aether A Fourth was Whether the globular Form of the smaller parcels of matter here upon the Earth as that of Fruits Pebbles or Fâ—ints c. which seem to have been a Liquor at first may not be caus'd by the heterogeneous ambient fluid For thus we see that melted Glass will be naturally form'd into a round Figure so likewise any small Parcel of any fusible body if it be perfectly enclosed by the Air will be driven into a globular Form and when cold will be found a solid Ball. This is plainly enough manifested to us by their way of making shot with the drops of Lead or a shower of Rain congealed in its falling into Hailstones and if you gently let fall a drop of water upon small sand or dust you shall find as 't were an artificial round stone quickly generated I cannot upon this occasion omit the mentioning of the strange kind of Grain which I have observed in a stone brought from Kettering in Northamptonshire and therefore called by Masons Kettering-Stone like to which are found also at Tormanton neer to Sudberry in Glocestershire For I found it to consist of a great number of small and almost globular parcels of matter which to my naked eye look'd much like the Cob or Spawn of a Herring though through a Microscope it looked like a great Beach of round Pebble stone such as I have often seen by the Sea-shore some of which I perceived to be hollow much like the broken Shels of Granadoes Which brings into my mind what I long since observ'd in the fiery Sparks that are struck out of a flint c. For having a great desire to see what was left behind after the Spark was gone out I purposely struck fire over a very white piece of Paper and observing diligently where some conspicuous sparks went out I found a very little black spot no bigger than the point of a Pin which through a Microscope appeared to be a perfectly round Ball looking much like a polisht ball of Steel insomuch that I was able to see the Image of the window reflected from it making the like Observation in very many others I found some to be hollow and to look like the broken shels of Grandoes much like that represented in the 4th Figure I cannot here stay to examine the particular Reasons of it but shall only hint that I imagine it to be some small parcel of the flint or steel for I find it may be of either which by the violence of the motion of the stroke most of which seems to be imprest upon those small parcels is made so glowing hot that 't is melted into a Vitrum which by the ambient Air is driven into a round Globul A Fifth thing which I thought worth Examination was Whether the motion of all kind of Springs might not be reduc'd to the Principle whereby the included heterogeneous fluid seems to be moved or to that whereby two solids as Marbles or the like are thrust and kept together by the Ambient fluid A Sixth thing was Whether the Rising and Ebullition of the water out of Springs Fountains which lie much higher from the Center of the earth than the superficies of the Sea from whence it seems to be derived may not be explicated by the Rising of water in a smaller Pipe For the Sea-water being as it were strain'd through the Pores or Crevices of the earth is as it were included in little Pipes where the pressure of the Air has not so great a power to resist its Rising But examining this way and finding in it several difficulties almost irremoveable I thought upon a way that would much more naturally and conceiveably explain it which was by this following Experiment I took a Glass Tube of the form of that described in the 6th Figure and chusing two heterogeneous fluids such as water and Oyl I poured in as much water as fill'd up the Pipes as high as A. B. then putting in some Oyle into the Tube A. C. I deprest the superficies A. of the water to E. and B. I raised to G. which was not so high perpendicularly as the superficies of the Oyle F. by the space F. I. wherefore the proportion of the gravity of these two Liquors was as G. H. to F. E. This Experiment I tried with several other Liquors and particularly with fresh water and salt which we made by dissolving Salt in warm water which two though they are nothing heterogeneous yet before they would perfectly mix one with another I made trial of the Experiment Nay letting the Tube wherein I tried the Experiment remain for many daies I observed them not to mix but the superficies of the fresh was rather more than less elevated above that of the salt Now the proportion of the gravity of Sea-water to that of River-water according to Stevinus and Varenius for I have not now the opportunity of making trial my self is as 46. to 45. that is 46. Ounces of the salt-water will take up no more Room than 45 of the fresh Or reciprocally 45 pints of salt water weigh as much as 46 of fresh Though I conceive the difference to be much more for I found the proportion of Brine to fresh water to be near 13 to 12 Supposing therefore G. H. M. to represent the Sea and F. I. the height of the Mountain above the Superficies of the Sea F. M. a Cavern in the Earth beginning at the bottom of the Sea and terminated at the top of the Mountain L. M the Sand at the bottom through which the water is as it were strained so as that the fresher parts are only permitted to transude and the saline kept back if therefore the proportion of G. M. to F. M. be as 45. to 46. then may the Cylinder of salt water G. M. make the Cylinder of fresh water to rise as high as E. and to run over at N. I cannot here stand to examine or confute their Opinion who make the depth of the Sea below its Superficies to be no more perpendicularly measur'd than the height of the Mountains above it 'T is enough for me to say there is no one of those that have vented it have experimentally known the perpendicular of either nor shall I here determine whether there may not be many other causes of the separation of the fresh water from the salt as perhaps some parts of the earth through which it is
to pass may contain a salt that mixing and uniting with the Sea salt may precipitate it much after the same manner as the Alkalizate and Acid Salts mix and precipitate each other in the preparation of Tartarum Vitriolatum I know not also whether the exceeding cold that must necessarily be at the bottom of the water may not help towards this separation for we find that warm water is able to dissolve and contain more salt than the same cold insomuch that Brines strongly impregnated by heat if let cool do suffer much of their salt to subside and chrystallize about the bottom and sides I know not also whether the exceeding pressure of the parts of the water one against another may not keep the Salt from descending to the very bottom as finding little or no room to insert it self between those parts protruded so violently together or else squeeze it upwards into the superiour parts of the Sea where it may more easily obtain room for it self amongst the parts of the water by reason that there is more heat and less pressure To this Opinion I was somwhat the more induced by the relations I have met with in several Geographical Writers of drawing fresh water from the bottom of the Sea which is salt above I cannot now stand to examine whether this natural perpetual motion may not artificially be imitated Nor can I stand to answer the Objections which may be made against this my Supposition As First How it comes to pass that there are somtimes salt Springs much higher than the Superficies of the water And Secondly Why Springs do not run faster and flower according to the varying height made of the Cylinder of Sea-water by the ebbing and flowing of the Sea As to the First In short I say the fresh water may receive again a saline Tincture near the Superficies of the Earth by passing through some salt Mines or else many of the saline parts of the Sea may be kept back though not all And as to the Second The same Spring may be fed and supply'd by divers Caverns coming from very far distant parts of the Sea so as that it may in one place be high in another low water and so by that means the Spring may be equally supply'd at all times Or else the Cavern may be so straight and narrow that the water not having so ready and free passage through it cannot upon so short and quick mutations of pressure be able to produce any sensible effect at such a distance Besides that to confirm this hypothesis there are many Examples found in Natural Historians of Springs that do ebb and flow like the Sea As particularly those recorded by the Learned Camden and after him by Speed to be found in this Island One of which they relate to be on the Top of a Mountain by the small Village Kilken in Flintshire Maris aemulus qui statis temporibus suas revomit resorbet Aquas which at certain times riseth and falleth after the manner of Sea-Tides A Second in Caermardenshire near Caermarden at a place call'd Cantred Bichan Qui ut scribit Giraldus naturali die bis undis deficiens toties exuberans marinas imitatur instabilitates That twice in four and twenty hours ebbing and flowing resembleth the uustable Motions of the Sea The Phanomena of which two may be easily made out by supposing their Cavern by which they are fed to arise from the bottom of the next Sea A Third is a Well upon the River Ogmore in Glamorganshire and near unto Newton of which Camhden relates himself to be certified by a Letter from a Learned Friend of his that observed it Fons abest hinc c. The Letter is a little too long to be inserted but the substance is this that this Well ebbs and flows quite contrarily to the flowing and ebbing of the Sea in those parts for 't is almost empty at Full Sea but full at Low water This may happen from the Channel by which it is supplied which may come from the bottom of a Sea very remote from those parts and where the Tides are much differing from those of the approximate shores A Fourth lies in Westmerland near the River Loder Qui instar Euripi saepius in die reciprocantibus undis fluit refluit which ebbs and flows many times a day This may proceed from its being supply'd from many Channels coming from several parts of the Sea lying sufficiently distant asunder to have the times of High-Water differing enough one from the other so as that whensoever it shall be High Water over any of those places where these Channels begin it shall likewise be so in the Well But this is but a Supposition A Seventh thing was Whether in general the Glutinousness of most bodies may not be partly attributed to this property For supposing glutinous bodies to be such as will easily conform themselves to the superficies of homogeneal bodies and being suffered for some time to rest in that Position until they grow hard the intercourse of the Air or other fluid body being hindred the force requisite to disjoyn those two superficies must necessarily be such as is able to preponderate and prevail against the pressure of the Air upon a superficies equal to that of the body which is toucht by the glutinous substance for these two touch so exactly that 't is impossible for the Air to get between until they are somwhat disjoyn'd by which means the pressure of the Air can only be against the two outward sides opposite to those which joyn them together This may be confirmed by the Experiment of two flat Marbles pieces of Glass and the like smooth bodies for if they be so exactly plain that by rubbing them together you can detrude the interjacent Air you shall find them stick so hard that an ordinary strength can hardly separate them especially if they be of any bigness This Property I say may at least be the cause why some bodies adhere to Glass and the like For I am not ignorant that as for Wood and many other porous bodies the glutinous substance may penetrate into their little cavities and so hardning become little Hooks or Buttons that may contribute much to the former Cohesion An Eighth Query was Whether the dissolution or mixing of several bodies whether fluid or solid with saline or other Liquors might not partly be attributed to this Principle of the congruity of those bodies and their dissolvents As of Salt in water Metals in several Menstruums Unctuous Gums in Oyles the Mixing of Wine and water c. And whether precipitation be not partly made from the same Principle of Incongruity I say partly because there are in some dissolutions some other Causes concurrent I shall lastly make a much more seemingly strange and unlikely Query and that is Whether this Principle well examined and explain'd may not be found a co-efficient in the most considerable Operations of Nature As in
those of Heat and Light and consequently of Rarefaction and Condensation Hardness or Solidity and Fluidness Perspicuity and Opacousness Refractions and Colours c. Nay I know not whether there may be many things done in Nature in which this may not be said to have a Finger This I may possibly further enquire into and examine if God grant me Life and Opportunity In the mean time I would not be thought guilty of that Errour which the thrice Noble and Learned Verulam justly takes notice of as such and cals Philosophiae Genus Empiricum quod in paucorum Experimentorum Angustiis Obscuritate fundatum est For I neither conclude from one single Experiment nor are the Experiments I make use of all made upon one Subject Nor wrest I any Experiment to make it quadrare with any preconceiv'd Notion But on the contrary I endeavour to be conversant in all kind of Experiments and all and every one of those Trials I make the standards as I may say or Touchstones by which I try all my former Notions whether they hold not in weight and measure and touch c. For as that Body is no other than a Counterfeit Gold which wants any one of the Proprieties of Gold such as are the Malleableness Weight Colour Fixtness in the Fire Indissolubleness in Aqua-fortis and the like though it has all the other so will all those notions be found to be false and deceitful that will not undergo all the Trials and Tests made of them by Experiments And therefore such as will not come up to the desired Apex of Perfection I rather wholly reject and take a new than by piecing and patching endeavour to retain the old as knowing old things to be rather made worse by mending than better And this course I learn'd from Nature whom we find neglectful of the old Body and suffering its Decaies and Infirmities to remain without repair and altogether sollicitous and careful of perpetuating the Species by new Individuals And 't is certainly the most likely way to erect a glorious and everlasting structure and Temple to Nature such as she will be found by any zealous Votary to reside in first to raze the old Pile built upon unstable Fancies and unsound opinions and to begin a new upon a sure Foundation of Experiments Thus Medaea when she renewed old Aeson first searches Heaven and Earth gathers and collects simples and Ingredients of all kinds nor would these do any thing till well mixt concocted and digested Omnia confudit summisque immiscuit ima Then we find her examine whether it will do what she expected Ecce vetus calido versatus stipes aheno Fit viridis primo nec longo tempore frondes Induit subito gravidis oneratur Olivis At quacunque cavo spumas ejecit aheno Ignis in terram guttas cecidere calentes Vernat humus floresque mollia pabula surgunt And finding it to come up to what she desired she then begins her great work Quae simul ac vidit stricto Medaea recludit Ense senis jugulum veteremque exire cruorem Passa replet succis After which what succeeded but a miraculous Renovation Barba comaeque Canitie posita nigrum rapuere colorem Pulsa fugit macies Abeunt pallorque situsque Adjectoque cavae supplentur corpore rugae Membraque luxuriant The Application of it is obvious and therefore to digress no further from the consideration of the Phaenomena more immediatly explicable by this Experiment we shall proceed to shew That As to the rising of water in a Filtre the reason of it will be manifest to him that does take notice that a Filtre is constituted of a great number of small long solid bodies which lie so close together that the Air in its getting in between them doth lose of its pressure that it has against the fluid without them by which means the water or liquor not finding so strong a resistance between them as is able to counter ballance the pressure on its superficies without is raised upwaâ—d till it meet with a pressure of the Air which is able to hinder it And as to the Rising of Oyl melted Tallow Spirit of Wine c. in the Weeck of a Candle or Lamp it is evident that it differs in nothing from the former save only in this that in a Filtre the Liquor descends and runs away by another part and in the Weeck the Liquor is dispersed and carried away by the Flame which what it is and how it consumes bodies I shall on some other occasion by many luciferous Experiments manifestly prove something there is ascribable to the heat for that it may rarifie the more volatil and spirituous parts of those combustible Liquors and so being made lighter than the Air it may be protruded upwards by that more ponderous fluid body in the Form of Vapours But this can be ascribed to the ascension of but a very little and most likely of that only which ascends without the Weeck as for the Rising of it in a Spunge Bread Cotton c. above the superficies of the subjacent Liquor what has been said about the Filtre if considered will easily suggest a reason considering that all these bodies are bound with small holes or pores From this same Principle also viz. the unequal pressure of the Air against the unequal superficies of the water proceeds the cause of the accession or incursion of any floating body against the sides of the containing Vessel or the appropinquation of two floating bodies as Bubbles Corks Sticks Straws c. one towards another As for instance Take a Glass-jar such as A. B. in the 7th Figure and filling it pretty near the top with water throw into it a small round piece of Cork as C. and pâ—unge it all over in water that it be wet so as that the water may rise up by the sides of it then placing it any where upon the superficies about an inch or one Inch and a quarter from any side and you shall perceive it by degrees to make perpendicularly toward the nearest part of the side and the nearer it approaches it the faster to be mov'd the reason of which Phaenomenon will be found no other than this that the Air has a greater pressure against the middle of the superficies than it has against those parts that approach nearer and are contiguous to the sides Now that the pressure is not so much may as I shewed before in the explication of the 3 d Figure be evinced from the rising of the water near the sides higher than that in the middle Hence the Ball having a stronger pressure against that side of it which respects the middle of the superficies than against that which respects the approximate side must necessarily move towards that part from whence it finds least resistance and so be accelerated as the resistance decreases Hence the more the water is raised under that part of its way it is passing above
the middle the faster it is moved And therefore you will find it to move faster in E. than in D. and in D. than in C. Neither could I find the floating substance to be moved at all until it were placed upon some part of the Superficies that was sensibly elevated above the height of the middle part Now that this may be the true cause you may try with a blown Bladder and an exactly roâ—nd Ball upon a very smooth Table For if the Ball be plac'd under a part of the Bladder w ch is upon one side of the middle of its pressure you press strongly against the Bladder you shall find the Ball mov'd from the middle towards the sides Having therefore shewn the reason of the motion of any float towards the sides the reason of the incursion of any two floating bodies will easily appear For the rising of the water against the sides of either of them is an Argument sufficient to shew the pressure of the Air to be there less then it is further from it where it is not so much elevated and therefore the reason of the motion of the other toward it will be the same as towards the side of the Glass only here from the same reason they are mutually mov'd toward each other whereas the side of the Glass in the former remains fixt If also you gently fill the Jar so full with water that the water is protuberant above the sides of the same piece of Cork that before did hasten towards the sides does now fly from it as fast towards the middle of the Superficies the reason of which will be found no other then this that the pressure of the Air is stronger against the sides of the superficies G. and H. then against the middle I. which may be argu'd from its being much lower then the middle and therefore the consecution will be the same as in the former It is very odd to one that considers not the reason of it to see two bodies of wood to approach each other as though they were indued with some magnetical vigour which brings into my mind what I formerly tried with a piece of Cork or such like body which I so ordered that by putting a little stick into the same water one part of the said Cork would approach and make toward the stick whereas another would discede and fly away nay it would have a kind of verticity so as that if the aequator as I may so speak of the Cork were placed towards the stick if let alone it would instantly turn its appropriate pole toward it and then run a tilt at it and this was only by taking a dry Cork and wetting one side of it with one small stroak for by this means gently putting it upon the water it would depress the superficies on every side of it that was dry and therefore the greatest pressure of the Air being near those sides caus'd it either to chase away or else to fly off from any other floting body whereas that side only against which the water ascended was thereby able to attract I cannot here stay to explain the Reasons of magnetical and electrical attraction nor the Reasons of gravity or magnetical direction and variation they being little or nothing at all to my present Subject and besides will afford matter enough to fill another sheet when I have leisure It remains only that I should determine now high the water or other Liquor may by this means be raised in a smaller Pipe above the superficies of that without it But to determine this will be exceeding difficult unless I could certainly know how much of the Air 's pressure is taken off by the smalness of such and such a Pipe and whether it may be wholly taken off that is whether there can be a hole or pore so small into which Air could not at all enter though water might with its whole force for were there such 't is manifest that the water might rise in it to some five or six and thirty English Foot high I know not whether there may not be such natural Pipes in the bodies of small Trees which we usually call their Pores But I have already pretergressed the bounds of a Sheet which I at first prescribed my self for the explication of this Phaenomenon and therefore I shall at present make AN END Of this much has bin â—â—id in the 31 〈◊〉 32 Experiments of the â—bove-mentiâ—ned Discourse â—f the Air 〈◊〉 more copiâ—usly exâ—lained in a Treatise of â—he same Honourable Auâ—hour now in â—he Presse